Automated, image-based disease measurement for phenotyping resistance to soybean frogeye leaf spot

BACKGROUND

Frogeye leaf spot is a disease of soybean, and there are limited sources of crop genetic resistance. Accurate quantification of resistance is necessary for the discovery of novel resistance sources, which can be accelerated by using a low-cost and easy-to-use image analysis system to phenotype the disease. The objective herein was to develop an automated image analysis phenotyping pipeline to measure and count frogeye leaf spot lesions on soybean leaves with high precision and resolution while ensuring data integrity.

RESULTS

The image analysis program developed measures two traits: the percent of diseased leaf area and the number of lesions on a leaf. Percent of diseased leaf area is calculated by dividing the number of diseased pixels by the total number of leaf pixels, which are segmented through a series of color space transformations and pixel value thresholding. Lesion number is determined by counting the number of objects remaining in the image when the lesions are segmented. Automated measurement of the percent of diseased leaf area deviates from the manually measured value by less than 0.05% on average. Automatic lesion counting deviates by an average of 1.6 lesions from the manually counted value. The proposed method is highly correlated with a conventional method using a 1-5 ordinal scale based on a standard area diagram. Input image compression was optimal at a resolution of 1500 × 1000 pixels. At this resolution, the image analysis method proposed can process an image in less than 10 s and is highly concordant with uncompressed images.

CONCLUSION

Image analysis provides improved resolution over conventional methods of frogeye leaf spot disease phenotyping. This method can improve the precision and resolution of phenotyping frogeye leaf spot, which can be used in genetic mapping to identify QTLs for crop genetic resistance and in breeding efforts for resistance to the disease.

The combined measurement of synovial markers in the diagnosis of periprosthetic joint infection

INTRODUCTION

Currently there is no single test for periprosthetic joint infection (PJI) that demonstrates an acceptable level of sensitivity. The aim of this pilot study was to identify a combination of biomarkers that could exclude periprosthetic infection prior to revision surgery in hip and knee arthroplasty. This would help in equivocal cases of PJI, such as those with low-virulence organisms, chronic low-grade infection or 'aseptic' loosening. Current research has focused on measuring the levels of biomarkers in the patient's synovial fluid, and these can be combined to improve accuracy.

METHODS

We selected synovial white cell count (SF-WCC) and C-reactive protein (SF-CRP), as they demonstrated an acceptable level of sensitivity and specificity which could be measured using existing equipment. One hundred and sixty-one synovial fluid samples from 134 patients were collected and analysed prospectively using calculated cut-off values of 10mg/l for SF-CRP and 3,000×10⁶/l for SF-WCC. Samples were deemed positive for infection when either of the SF-CRP or SF-WCC values were above the cut-off.

RESULTS

The combined test demonstrated a sensitivity greater than 98.5% and specificity above 80% in all samples analysed or looked at separately for total hip replacement and total knee replacement infections. All ten aspirates taken from chronically infected joints tested positive.

CONCLUSIONS

The combination of SF-CRP and SF-WCC measurement has been shown to have high sensitivity of over 99% in detecting both acute and chronic PJI in both hip and knee arthroplasty. This ability of the test to exclude infection with a high degree of certainty will help in preoperative planning of PJIs.

1585 The “6Pm Series” Addressing Medical Education for Final Year Medical Students During the Pandemic

Aim

Free clinical teaching online delivered by NHS junior doctors to address a drop in face-to-face teaching.

Method

We created a block-based syllabus of topics that are commonly examined and created an SBA format series of online lectures. The lectures were delivered online and the lectures were carried out by NHS doctors. We delivered 30 continuous lectures in a 30-day period that covered a variety of topics. Each lecture lasted between 45 to 60 minutes and featured real time interactive mcqs which the students had a limited time to answer to simulate exam conditions. We also maintained a unique conference like format where the lecture provider would also be assisted by a ‘host' who would provide an environment that simulated a real-life lecture with a back-and-forth conversation. Lastly each session was reinforced with a feedback survey at the end which helped us improve our service but also provided key indicators on the needs of the audience.

Results

We were able to provide a series of lectures that on average had a viewership of 120-150 attendees per lecture and grew a social media following of 3500 people. Although the following on social media is not a full reflection of our reach. A good indication is our prescribing safety assessment series which attracted over 2000 people interested and 260 confirmed for one event.

Conclusions

We feel that the format we followed in delivering medical teaching provided a very effective format and we hope to continue this into the future.

Momentum-space signatures of Berry flux monopoles in the Weyl semimetal TaAs

Since the early days of Dirac flux quantization, magnetic monopoles have been sought after as a potential corollary of quantized electric charge. As opposed to magnetic monopoles embedded into the theory of electromagnetism, Weyl semimetals (WSM) exhibit Berry flux monopoles in reciprocal parameter space. As a function of crystal momentum, such monopoles locate at the crossing point of spin-polarized bands forming the Weyl cone. Here, we report momentum-resolved spectroscopic signatures of Berry flux monopoles in TaAs as a paradigmatic WSM. We carried out angle-resolved photoelectron spectroscopy at bulk-sensitive soft X-ray energies (SX-ARPES) combined with photoelectron spin detection and circular dichroism. The experiments reveal large spin- and orbital-angular-momentum (SAM and OAM) polarizations of the Weyl-fermion states, resulting from the broken crystalline inversion symmetry in TaAs. Supported by first-principles calculations, our measurements image signatures of a topologically non-trivial winding of the OAM at the Weyl nodes and unveil a chirality-dependent SAM of the Weyl bands. Our results provide directly bulk-sensitive spectroscopic support for the non-trivial band topology in the WSM TaAs, promising to have profound implications for the study of quantum-geometric effects in solids.

Weyl semimetals exhibit Berry flux monopoles in momentum-space, but direct experimental evidence has remained elusive. Here, the authors reveal topologically non-trivial winding of the orbital-angular-momentum at the Weyl nodes and a chirality-dependent spin-angular-momentum of the Weyl bands, as a direct signature of the Berry flux monopoles in TaAs.

A novel adult plant leaf rust resistance gene Lr2K38 mapped on wheat chromosome 1AL

Soft red winter wheat (SRWW) cultivar AGS 2038 has a high level of seedling and adult plant leaf rust (LR) resistance. To map and characterize LR resistance in AGS 2038, a recombinant inbred line (RIL) population consisting of 225 lines was developed from a cross between AGS 2038 and moderately resistant line UGA 111729. The parents and RIL population were phenotyped for LR response in three field environments at Plains and Griffin, GA, in the 2017-2018 and 2018-2019 growing seasons, one greenhouse environment at the adult-plant stage, and at seedling stage. The RIL population was genotyped with the Illumina iSelect 90K SNP marker array, and a total of 7667 polymorphic markers representing 1513 unique loci were used to construct a linkage map. Quantitative trait loci (QTL) analysis detected six QTL, QLr.ags-1AL, QLr.ags-2AS, QLr.ags-2BS1, QLr.ags-2BS2, QLr.ags-2BS3, and QLr.ags-2DS, for seedling and adult plant LR resistance. Of these, the major adult plant leaf rust resistance QTL, QLr.ags-1AL, was detected on all field and greenhouse adult plant tests and explained up to 34.45% of the phenotypic variation. QLr.ags-1AL, tightly flanked by IWB20487 and IWA4022 markers, was contributed by AGS 2038. Molecular marker analysis using a diagnostic marker linked to Lr59 showed that QLr.ags-1AL was different from Lr59, the only known LR resistance gene on 1AL. Therefore, the QTL was temporarily designated as Lr2K38. Lr2K38-linked marker IWB20487 was highly polymorphic among 30 SRWW lines and should be useful for selecting the Lr2K38 in wheat breeding programs.

The use of 4-Hexylresorcinol as antibiotic adjuvant

Ever decreasing efficiency of antibiotic treatment due to growing antibiotic resistance of pathogenic bacteria is a critical issue in clinical practice. The two generally accepted major approaches to this problem are the search for new antibiotics and the development of antibiotic adjuvants to enhance the antimicrobial activity of known compounds. It was therefore the aim of the present study to test whether alkylresorcinols, a class of phenolic lipids, can be used as adjuvants to potentiate the effect of various classes of antibiotics. Alkylresorcinols were combined with 12 clinically used antibiotics. Growth-inhibiting activity against a broad range of pro- and eukaryotic microorganisms was determined. Test organisms did comprise 10 bacterial and 2 fungal collection strains, including E. coli and S. aureus, and clinical isolates of K. pneumoniae. The highest adjuvant activity was observed in the case of 4-hexylresorcinol (4-HR), a natural compound found in plants with antimicrobial activity. 50% of the minimal inhibitory concentration (MIC) of 4-HR caused an up to 50-fold decrease in the MIC of antibiotics of various classes. Application of 4-HR as an adjuvant revealed its efficiency against germination of bacterial dormant forms (spores) and prevented formation of antibiotic-tolerant persister cells. Using an in vivo mouse model of K. pneumoniae-induced sepsis, we could demonstrate that the combination of 4-HR and polymyxin was highly effective. 75% of animals were free of infection after treatment as compared to none of the animals receiving the antibiotic alone. We conclude that alkylresorcinols such as 4-HR can be used as an adjuvant to increase the efficiency of several known antibiotics. We suggest that by this approach the risk for development of genetically determined antibiotic resistance can be minimized due to the multimodal mode of action of 4-HR.

First Report of Fusarium poae Causing Fusarium Head Blight of Wheat in Georgia, USA

Fusarium head blight (FHB) is one of the most troublesome fungal diseases challenging US wheat (Triticum aestivum L.) production (Savary et al. 2019). Harmful mycotoxin contamination, primarily due to deoxynivalenol (DON) in the Fusarium-damaged kernels (FDK), can negatively impact human and livestock health (McMullen et al. 1997). Although Fusarium graminearum is the primary causal agent of FHB, several other species including F. poae could pose a risk by producing dangerous mycotoxins such as nivalenol, DON, HT-2, and T-2 (Stenglein 2009). Severe FHB epidemics on wheat have occurred in recent years along with increased corn acreage across the southeast US specifically in Georgia (Ghimire et al. 2020). Five symptomatic wheat heads displaying bleaching symptoms were randomly collected from 19 different fields across 13 counties of Georgia in late spring of 2018. Infected kernels were dipped in 6% sodium hypochlorite for 10 min and rinsed three times with sterilized water. Blot dried kernels were placed on potato dextrose agar (PDA) and incubated for 7 days at 25°C under 12-h photoperiod. Three isolates (GA18W-2.1.6, GA18W-6.1.4, and GA18W-10.2.3) from Terrell, Peach, and Sumter counties exhibited dense, whitish mycelium colony typical of F. poae (Leslie and Summerell 2006). When grown in carboxymethylcellulose broth, isolates produced globose to piriform microconidia (5.1 to 12.4 µm by 4.4 to 11.2 µm) that were aseptate or had a single septation. The morphological identification was further confirmed by DNA sequencing. Single hyphal tip isolates were grown on cellophane overlain on PDA for 10 days. Fungal DNA was extracted using a Qiagen DNeasy Plant Mini Kit. Genomic DNA was sequenced using TEF1 and TEF2 primer pairs that target the translation elongation factor 1-α (EF1-α) locus (O'Donnell et al. 1998). BLASTn query of the obtained sequences of GA18W-2.1.6 (accession no. MT856907) and GA18W-10.2.3 (accession no. MT856909) were identified as F. poae with a 99% sequence homology with GenBank reference accession MK629641, while GA18W-6.1.4 (accession no. MT856908) displayed 100% similarity with F. poae accession KJ947343. Koch's postulates were performed under greenhouse conditions. Three seeds of the FHB susceptible wheat cultivar 'SS8641' were planted in individual cone-tainers with three replications (two cone-tainers/replicate). Wheat plants were vernalized for six weeks and then moved back to the greenhouse. Each F. poae isolate was spray inoculated (50,000 spores/ml) at the flowering stage onto 18-24 wheat heads. A field isolate of F. graminearum was included as a positive control whereas heads mock-inoculated with water were used as a negative control. Inoculated wheat heads were incubated in black plastic bags for 48 hours. Disease severity and FDK were recorded three weeks post inoculation. Disease severities were 6.7% (GA18W-2.1.6), 8.3% (GA18W-10.2.3), and 15.2% (GA18W-6.1.4) compared to 90.0% in the positive control similar to Arrúa et al (2019). No symptoms were observed in the negative control. FDK was 18% (GA18W-2.1.6), 28% (GA18W-10.2.3) and 44% (GA18W-6.1.4). F. poae was re-isolated from the infected heads and found to be morphologically identical to the isolates used for inoculation. To our knowledge, this is the first report of F. poae associated with FHB of wheat in the state of Georgia, USA. F. poae isolates from Georgia might produce mycotoxins in addition to reducing grain yield which needs further study.

Genome-Wide Association Study of a Worldwide Collection of Wheat Genotypes Reveals Novel Quantitative Trait Loci for Leaf Rust Resistance

The emergence of new virulent Puccinia triticina races requires a continuous search for novel sources of resistance to combat leaf rust (LR) disease Twenty-two wheat genotypes resistant to four P. triticina races were identified in this study A genome-wide association study detected 11 quantitative trait loci for LR resistance; five of them were detected on genomic regions where no LR resistant genes have been detected. Wheat (Triticum aestivum L.) production worldwide is being challenged by several biotic and abiotic factors. Leaf rust (LR), caused by Puccinia triticina, is a major biotic constraint of wheat production worldwide. Genetic resistance is the most efficient and cost-effective way to control LR. Seventy-nine LR resistance genes have been identified to date but the frequent emergence of new virulent P. triticina races every year demands a constant search for new sources of resistance with novel quantitative trait loci (QTL) or genes. The objectives of this study were to identify putative novel sources of effective resistance against the current prevalent races of P. triticina in the southeast United States and to map genomic loci associated with LR resistance via a genome-wide association study (GWAS) approach. Evaluation of 331 diverse wheat genotypes against four prevalent P. triticina races (MFGKG, MBTNB, MCTNB, and TCRKG) revealed that the majority of the genotypes were susceptible and only 22 genotypes (6.6%) were resistant to all four P. triticina races. The GWAS detected 11 QTL on nine chromosomes for LR resistance. Of these, six QTL were identified in the vicinity of known genes or QTL; therefore, more studies are warranted to determine their relationship. Five QTL (QLr.uga-1AL, QLr.uga-4AS, QLu.uga-5AS, QLr.uga-5AL, and QLr.uga-7AS) were identified on genomic regions where no LR resistance genes have been identified in wheat, representing potential novel loci for LR resistance. The highly resistant wheat genotypes and novel QTL reported in this study could be used in breeding programs to improve LR resistance.

Recovery of High-Energy Photoelectron Circular Dichroism through Fano Interference

It is commonly accepted that the magnitude of a photoelectron circular dichroism (PECD) is governed by the ability of an outgoing photoelectron wave packet to probe the chiral asymmetry of a molecule. To be able to accumulate this characteristic asymmetry while escaping the chiral ion, photoelectrons need to have relatively small kinetic energies of up to a few tens of electron volts. Here, we demonstrate a substantial PECD for very fast photoelectrons above 500 eV kinetic energy released from methyloxirane by a participator resonant Auger decay of its lowermost O 1s excitation. This effect emerges as a result of the Fano interference between the direct and resonant photoionization pathways, notwithstanding that their individual effects are negligibly small. The resulting dichroic parameter has an anomalous dispersion: It changes its sign across the resonance, which can be considered as an analogue of the Cotton effect in the x-ray regime.

Symmetry breakdown of electron emission in extreme ultraviolet photoionization of argon

Short wavelength free-electron lasers (FELs), providing pulses of ultrahigh photon intensity, have revolutionized spectroscopy on ionic targets. Their exceptional photon flux enables multiple photon absorptions within a single femtosecond pulse, which in turn allows for deep insights into the photoionization process itself as well as into evolving ionic states of a target. Here we employ ultraintense pulses from the FEL FERMI to spectroscopically investigate the sequential emission of electrons from gaseous, atomic argon in the neutral as well as the ionic ground state. A pronounced forward-backward symmetry breaking of the angularly resolved emission patterns with respect to the light propagation direction is experimentally observed and theoretically explained for the region of the Cooper minimum, where the asymmetry of electron emission is strongly enhanced. These findings aim to originate a better understanding of the fundamentals of photon momentum transfer in ionic matter.

Accurate prediction of X-ray pulse properties from a free-electron laser using machine learning

Free-electron lasers providing ultra-short high-brightness pulses of X-ray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of matter. To fully harness this potential, we must accurately know the X-ray properties: intensity, spectrum and temporal profile. Owing to the inherent fluctuations in free-electron lasers, this mandates a full characterization of the properties for each and every pulse. While diagnostics of these properties exist, they are often invasive and many cannot operate at a high-repetition rate. Here, we present a technique for circumventing this limitation. Employing a machine learning strategy, we can accurately predict X-ray properties for every shot using only parameters that are easily recorded at high-repetition rate, by training a model on a small set of fully diagnosed pulses. This opens the door to fully realizing the promise of next-generation high-repetition rate X-ray lasers.

Circular dichroism measurements at an x-ray free-electron laser with polarization control

A non-destructive diagnostic method for the characterization of circularly polarized, ultraintense, short wavelength free-electron laser (FEL) light is presented. The recently installed Delta undulator at the LCLS (Linac Coherent Light Source) at SLAC National Accelerator Laboratory (USA) was used as showcase for this diagnostic scheme. By applying a combined two-color, multi-photon experiment with polarization control, the degree of circular polarization of the Delta undulator has been determined. Towards this goal, an oriented electronic state in the continuum was created by non-resonant ionization of the O2 1s core shell with circularly polarized FEL pulses at hν ≃ 700 eV. An also circularly polarized, highly intense UV laser pulse with hν ≃ 3.1 eV was temporally and spatially overlapped, causing the photoelectrons to redistribute into so-called sidebands that are energetically separated by the photon energy of the UV laser. By determining the circular dichroism of these redistributed electrons using angle resolving electron spectroscopy and modeling the results with the strong-field approximation, this scheme allows to unambiguously determine the absolute degree of circular polarization of any pulsed, ultraintense XUV or X-ray laser source.

Single Shot Polarization Characterization of XUV FEL Pulses from Crossed Polarized Undulators

Polarization control is a key feature of light generated by short-wavelength free-electron lasers. In this work, we report the first experimental characterization of the polarization properties of an extreme ultraviolet high gain free-electron laser operated with crossed polarized undulators. We investigate the average degree of polarization and the shot-to-shot stability and we analyze aspects such as existing possibilities for controlling and switching the polarization state of the emitted light. The results are in agreement with predictions based on Gaussian beams propagation.

Fine Mapping and Characterization of Candidate Genes that Control Resistance to Cercospora sojina K. Hara in Two Soybean Germplasm Accessions

Frogeye leaf spot (FLS), caused by the fungus Cercospora sojina K. Hara, may cause a significant yield loss to soybean growers in regions with a warm and humid climate. Two soybean accessions, PI 594891 and PI 594774, were identified to carry a high level of resistance similar to that conditioned by the Rcs3 gene in 'Davis'. Previously, we reported that the resistance to FLS in these two plant introductions (PIs) was controlled by a novel gene (s) on chromosome 13 that is different from Rcs3. To fine-map the novel FLS resistance gene(s) in these two PIs, F2: 3 seeds from the crosses between PI 594891 and PI 594774, and the FLS susceptible genotype 'Blackhawk' were genotyped with SNP markers that were designed based on the SoySNP50k iSelect BeadChip data to identify recombinant events and locate candidate genes. Analysis of lines possessing key recombination events helped narrow down the FLS-resistance genomic region in PI 594891 from 3.3 Mb to a 72.6 kb region with five annotated genes. The resistance gene in PI 594774 was fine-mapped into a 540 kb region that encompasses the 72.6 kb region found in PI 594891. Sequencing five candidate genes in PI 594891 identified three genes that have several mutations in the promoter, intron, 5', and 3' UTR regions. qPCR analysis showed a difference in expression levels of these genes in both lines compared to Blackhawk in the presence of C. sojina. Based on phenotype, genotype and haplotype analysis results, these two soybean accessions might carry different resistance alleles of the same gene or two different gene(s). The identified SNPs were used to develop Kompetitive Allele Specific PCR (KASP) assays to detect the resistance alleles on chromosome 13 from the two PIs for marker-assisted selection.

Activation of the ACE2/Ang-(1-7)/Mas pathway reduces oxygen-glucose deprivation-induced tissue swelling, ROS production, and cell death in mouse brain with angiotensin II overproduction

We previously demonstrated that mice which overexpress human renin and angiotensinogen (R+A+) show enhanced cerebral damage in both in vivo and in vitro experimental ischemia models. Angiotensin-converting enzyme 2 (ACE2) counteracts the effects of angiotensin (Ang-II) by transforming it into Ang-(1-7), thus reducing the ligand for the AT1 receptor and increasing stimulation of the Mas receptor. Triple transgenic mice, SARA, which specifically overexpress ACE2 in neurons of R+A+ mice were used to study the role of ACE2 in ischemic stroke using oxygen and glucose deprivation (OGD) of brain slices as an in vitro model. We examined tissue swelling, the production of reactive oxygen species (ROS), and cell death in the cerebral cortex (CX) and the hippocampal CA1 region during OGD. Expression levels of NADPH oxidase (Nox) isoforms, Nox2 and Nox4 were measured using western blots. Results show that SARA mice and R+A+ mice treated with the Mas receptor agonist Ang-(1-7) had less swelling, cell death, and ROS production in CX and CA1 areas compared to those in R+A+ animals. Treatment of slices from SARA mice with the Mas antagonist A779 eliminated this protection. Finally, western blots revealed less Nox2 and Nox4 expression in SARA mice compared with R+A+ mice both before and after OGD. We suggest that reduced brain swelling and cell death observed in SARA animals exposed to OGD result from diminished ROS production coupled with lower expression of Nox isoforms. Thus, the ACE2/Ang-(1-7)/Mas receptor pathway plays a protective role in brain ischemic damage by counteracting the detrimental effects of Ang-II-induced ROS production.

Thiol changes during epididymal maturation: a link to flagellar angulation in mouse spermatozoa?

Caput epididymal wild-type spermatozoa and cauda epididymal spermatozoa from mice null for the adenylyl cyclase Adcy10 gene are immotile unless stimulated by a membrane-permeant cyclic AMP analogue. Both types of spermatozoa exhibit flagellar angulation where the head folds back under these conditions. As sperm proteins undergo oxidation of sulfhydryl groups and the flagellum becomes more stable to external forces during epididymal transit, we hypothesized that ADCY10 is involved in a mechanism regulating flagellar stabilization. Although no differences were observed in global sulfhydryl status between caput and cauda epididymal spermatozoa from wild-type or Adcy10-null mice, two-dimensional fluorescence difference gel electrophoresis was performed to identify specific mouse sperm proteins containing sulfhydryl groups that became oxidized during epididymal maturation. A-kinase anchor protein 4, fatty acid-binding protein 9 (FABP9), glutathione S-transferase mu 5 and voltage-dependent anion channel 2 exhibited changes in thiol status between caput and cauda epididymal spermatozoa. The level and thiol status of each of these proteins were quantified in wild-type and Adcy10-null cauda epididymal spermatozoa. No differences in the abundance of any protein were observed; however, FABP9 in Adcy10-null cauda epididymal spermatozoa contained fewer disulfide bonds than wild-type sperm cells. In caput epididymal spermatozoa, FABP9 was detected in the cytoplasmic droplet, principal piece, midpiece, and non-acrosomal area of the head. However, in cauda epididymal spermatozoa, this protein localized to the perforatorium, post-acrosomal region and principal piece. Together, these results suggest that thiol changes during epididymal maturation have a role in the stabilization of the sperm flagellum.

Thiol changes during epididymal maturation: a link to flagellar angulation in mouse spermatozoa?

Caput epididymal wild-type spermatozoa and cauda epididymal spermatozoa from mice null for the adenylyl cyclase Adcy10 gene are immotile unless stimulated by a membrane-permeant cyclic AMP analogue. Both types of spermatozoa exhibit flagellar angulation where the head folds back under these conditions. As sperm proteins undergo oxidation of sulfhydryl groups and the flagellum becomes more stable to external forces during epididymal transit, we hypothesized that ADCY10 is involved in a mechanism regulating flagellar stabilization. Although no differences were observed in global sulfhydryl status between caput and cauda epididymal spermatozoa from wild-type or Adcy10-null mice, two-dimensional fluorescence difference gel electrophoresis was performed to identify specific mouse sperm proteins containing sulfhydryl groups that became oxidized during epididymal maturation. A-kinase anchor protein 4, fatty acid-binding protein 9 (FABP9), glutathione S-transferase mu 5 and voltage-dependent anion channel 2 exhibited changes in thiol status between caput and cauda epididymal spermatozoa. The level and thiol status of each of these proteins were quantified in wild-type and Adcy10-null cauda epididymal spermatozoa. No differences in the abundance of any protein were observed; however, FABP9 in Adcy10-null cauda epididymal spermatozoa contained fewer disulfide bonds than wild-type sperm cells. In caput epididymal spermatozoa, FABP9 was detected in the cytoplasmic droplet, principal piece, midpiece, and non-acrosomal area of the head. However, in cauda epididymal spermatozoa, this protein localized to the perforatorium, post-acrosomal region and principal piece. Together, these results suggest that thiol changes during epididymal maturation have a role in the stabilization of the sperm flagellum.

Utilization of a novel unidirectional knotless suture during minimal access procedures in pediatric surgery

BACKGROUND

The application of minimally invasive surgery (MIS) for advanced procedures in children is logical. However, the intracorporeal placement and tying of suture can be challenging, leading to prolonged anesthesia and morbidity. We describe our initial experience with the use of a novel unidirectional barbed knotless suture (V-LOC, Covidien, Mansfield, MA) that permits a safe and efficient advanced MIS reconstruction in infants and children.

METHODS

From August 2010 to February 2012, 11 infants and children underwent diaphragmatic reconstruction utilizing either the absorbable or the permanent V-LOC suture. Data retrieval included gender, weight, diagnosis, operative time, complications and follow up.

RESULTS

Thoracoscopic or laparoscopic repairs were carried out in all children. Two of the infants with congenital diaphragmatic hernia of Bochdalek (CDH) developed a recurrence at 4 and 6 months of age and required reoperation. There were no other complications or recurrence in the remaining 9 children, and there were no mortalities in the group.

CONCLUSION

This is the first study to evaluate the use of the unidirectional barbed knotless suture in pediatric surgery. We demonstrate that the use of the V-LOC barbed suture is an innovative, safe and time saving option for pediatric MIS. Prospective analysis with long-term follow-up is required to confirm these initial results and to ascertain if this novel approach can be utilized in other pediatric surgical conditions.

High adenylyl cyclase activity and in vivo cAMP fluctuations in corals suggest central physiological role

Corals are an ecologically and evolutionarily significant group, providing the framework for coral reef biodiversity while representing one of the most basal of metazoan phyla. However, little is known about fundamental signaling pathways in corals. Here we investigate the dynamics of cAMP, a conserved signaling molecule that can regulate virtually every physiological process. Bioinformatics revealed corals have both transmembrane and soluble adenylyl cyclases (AC). Endogenous cAMP levels in live corals followed a potential diel cycle, as they were higher during the day compared to the middle of the night. Coral homogenates exhibited some of the highest cAMP production rates ever to be recorded in any organism; this activity was inhibited by calcium ions and stimulated by bicarbonate. In contrast, zooxanthellae or mucus had >1000-fold lower AC activity. These results suggest that cAMP is an important regulator of coral physiology, especially in response to light, acid/base disturbances and inorganic carbon levels.

The growth and electronic structure of azobenzene-based functional molecules on layered crystals

In situ ultraviolet photoelectron spectroscopy is used to study the growth of ultrathin films of azobenzene-based functional molecules (azobenzene, Disperse Orange 3 and a triazatriangulenium platform with an attached functional azo-group) on the layered metal TiTe(2) and on the layered semiconductor HfS(2) at liquid nitrogen temperatures. Effects of intermolecular interactions, of the substrate electronic structure, and of the thermal energy of the sublimated molecules on the growth process and on the adsorbate electronic structure are identified and discussed. A weak adsorbate-substrate interaction is particularly observed for the layered semiconducting substrate, holding the promise of efficient molecular photoswitching.

Comparison of international breast cancer guidelines: are we globally consistent? cancer guideline AGREEment

BACKGROUND

Evidence-based guidelines are used in health care systems throughout the world to aid in treatment decisions and to ensure quality and consistency in patient care. In breast oncology, guidelines for care are published by several internationally recognized organizations, including those from the United States, Canada, and the United Kingdom. The present study compared clinical breast cancer guidelines from the American Society of Clinical Oncology (ASCO, United States), Cancer Care Ontario (CCO, Canada), and the National Institute for Health and Clinical Excellence (NICE, United Kingdom) to determine the quality and consistency of content across international organizations.

METHODS

We searched for breast cancer guidelines published by ASCO, CCO, and NICE. Guidelines on the same theme were identified across organizations and appraised by 4 independent reviewers using the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument. Content of each guideline was also scored for consistency in overall recommendations across organizations and for consistency in cited evidence.

RESULTS

The quality of breast cancer guidelines produced by the targeted organizations was consistently good in the areas of Scope and Purpose, Rigor of Development, and Clarity and Presentation, but variable in the domains of Stakeholder Involvement, Applicability, and Editorial Independence. The content of the guidelines varied slightly in the strength of their recommendations.

CONCLUSIONS

Our review demonstrated consistency in quality and content for breast cancer practice guidelines published by various organizations. Future guidelines developed by these organizations should focus on how to implement and measure uptake of a guideline.

Characterization of a major QTL for adult plant resistance to stripe rust in US soft red winter wheat

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is an important disease of soft red winter wheat in the eastern region of the USA. Pioneer 26R61 has provided effective resistance to stripe rust for 10 years. To elucidate the genetic basis of the resistance, a mapping population of 178 recombinant inbred lines (RILs) was developed using single-seed descent from a cross between Pioneer 26R61 and the susceptible cultivar AGS 2000. A genetic map with 895 markers covering all 21 chromosomes was used for QTL analysis. One major QTL was detected, explaining up to 56.0% of the mean phenotypic variation, flanked by markers Xbarc124 and Xgwm359, and assigned to the distal 22% of the short arm of wheat chromosome 2A. Evidence showed that it was different from Yr17 derived from Ae. ventricosa, the only formally named Yr gene in 2AS, and the QTL was temporarily designated as YrR61. In addition, a minor QTL, QYr.uga-6AS, probably conditioned high-temperature adult plant resistance. The QTL explained 6-7% of the trait variation. Preliminary test of the flanking markers for YrR61, in two cultivars and two promising breeding lines with Pioneer 26R61 in their pedigree, indicated that YrR61 was present in these cultivars and lines, and these markers could therefore be used in marker-assisted selection.

Abstract P5-15-05: Applicability of Breast Cancer Guidelines and Knowledge Translation in a Community Oncology Setting

Background: The quality of a guideline may impact adherence to that guideline. Cancer Care Ontario (CCO) produces guidelines to help manage all stages of disease. CCO's staging and follow-up guideline suggests patients (pts) with stage I breast cancer require no further staging investigations, bone scan for stage II disease, and for stage III disease in addition to bone scan, chest and abdominal imaging. The guideline on bisphosphonate (BP) use in metastatic breast cancer pts indicates that all pts with bone metastases should be offered a BP. We assessed the efficacy of knowledge translation of these guidelines at a community oncology centre by correlating rate of adherence with the quality of the guideline as scored using the Appraisal of Guidelines for Research and Evaluation (AGREE) Instrument.

Methods: The quality of 2 breast cancer guidelines from CCO were assessed using the AGREE instrument. Two cohort studies of breast cancer pts seen were then conducted to evaluate the adherence to these guidelines. Specifically, staging investigations ordered on pts seen in our multidisciplinary clinic between January 2009 and April 2010 were recorded and correlated to pathological stage of disease. Our second cohort study reviewed breast cancer pts with bone metastases who died between 1999 and 2009, and initiation of a BP was recorded in order to determine adherence to the second guideline.

Results: Inadequate adherence was identified and correlated with low applicability scores for these two guidelines (58% and 33% respectively). Only 68 pts (61%) with bone metastases received BP for treatment between 1999 to 2009. 129 pts (56%) underwent unnecessary staging investigations.

Discussions: Non-chemotherapy breast cancer guidelines by CCO scored low in the field of applicability; this was confirmed by two retrospective cohort studies. Improvement in knowledge translation strategies are needed to improve adherence to practice guidelines set out by this national organization.

[Ileocoecal intussusception of the terminal ileum caused by a carcinoid tumor]

Intussusception of the intestine is a frequent reason for intestinal obstruction in infants; the course is acute but the causes are often not recognizable. In adults intussusception is the cause for bowel obstruction in only 1% of cases. The course is subacute and in over 90% a benign or malignant process in this part of the intestine is found. We report the case of a 45-year-old male with abdominal discomfort, increasing over weeks. The preoperative ultrasonography and computed tomography of the abdomen revealed the typical finding of ileocoecal intussusception. An ileocoecal resection was performed. The histopathological workup showed a small carcinoid tumour of the terminal ileum.

Tracing blood units to their recipients: results of a two-centre study

An important principle of the use of blood components is the ability to trace them from the donor to the recipient. This study set out to establish whether there was sufficient documentation in patient case notes to confirm the transfusion of blood components in a sample of computer blood bank records at two large teaching hospitals in UK. The criteria for verification of transfusion were taken from guidelines from the British Committee for Standards in Haematology (Transfusion Medicine 1999, 9, 227-238). The blood bank computer records indicated that 486 units of blood components were issued and not returned to the blood bank for 80 patients during a 2-month period. Of the 486 units, transfusion of 409 units (84%) was verified against patient notes, but 77 units (16%) could not be verified as received by the patient. The study showed that documentation of transfusions was variable. For example, written prescriptions were only found for 204 units (42%). These results have implications for 'lookback studies' involving blood transfusion. Further efforts are required to educate those involved in transfusing blood about the need for accurate documentation.

CO(2)/HCO(3)(-)-responsive soluble adenylyl cyclase as a putative metabolic sensor

Cyclic AMP (cAMP) is an evolutionarily conserved regulator of metabolism. Recently, we identified a novel mammalian source of cAMP - soluble adenylyl cyclase (sAC) - that is regulated directly by bicarbonate ions (HCO(3)(-)). As the concentration of HCO(3)(-) reflects cellular levels of carbon dioxide (CO(2)), energy-generating metabolic processes (which increase intracellular CO(2)) are poised to activate bicarbonate-responsive sAC. This direct link between metabolic activity, sAC and cAMP could represent an evolutionarily conserved mechanism of metabolic feedback regulation.

Bicarbonate-regulated soluble adenylyl cyclase

Soluble adenylyl cyclase (sAC) represents a novel form of mammalian adenylyl cyclase structurally, molecularly, and biochemically distinct from the G protein-regulated, transmembrane adenylyl cyclases (tmACs). sAC possesses no transmembrane domains and is insensitive to classic modulators of tmACs, such as heterotrimeric G proteins and P site ligands. Thus, sAC defines an independently regulated cAMP signaling system within mammalian cells. sAC is directly stimulated by bicarbonate ion both in vivo in heterologously expressing cells and in vitro using purified protein. sAC appears to be the predominant form of adenylyl cyclase (AC) in mammalian sperm, and its direct activation by bicarbonate provides a mechanism for generating the cAMP required to complete the bicarbonate-induced processes necessary for fertilization, including hyperactivated motility, capacitation, and the acrosome reaction. Immunolocalization studies reveal sAC is also abundantly expressed in other tissues which respond to bicarbonate or carbon dioxide levels suggesting it may function as a general bicarbonate/CO(2) sensor throughout the body.

A helical lid converts a sulfotransferase to a dehydratase

We report here the crystal structure of retinol dehydratase, an enzyme that catalyzes the synthesis of anhydroretinol. The enzyme is a member of the sulfotransferase superfamily and its crystal structure reveals the insertion of a helical lid into a canonical sulfotransferase fold. Site-directed mutations demonstrate that this inserted lid is necessary for anhydroretinol production but not for sulfonation; thus, insertion of a helical lid can convert a sulfotransferase into a dehydratase.

Characterization of excimer lasers for application to lenslet array homogenizers

We investigate the best method of characterizing high-divergence lasers, such as excimer lasers, to suppress fine-scale intensity nonuniformity that is due to coherence effects of lenslet homogenizers. We show by a detailed analysis of the lenslet homogenizer that, for highest accuracy, a direct measurement of the value of the autocorrelation function should be made at the separation p of the lenslet elements, identified as the critical spatial period. We show that the commonly used characterization of lasers by the 1/e(2) width of the angular divergence is not the most accurate test and may overstate or understate the effectiveness of a given laser.

Crystallization of retinol dehydratase from Spodoptera frugiperda: improvement of crystal quality by modification by ethylmercurythiosalicylate

Retinol dehydratase is a sulfotransferase which is presumed to catalyze the dehydration of its substrate via a transient retinyl sulfate intermediate. Crystals (space group P2(1), unit-cell parameters a = 82.05, b = 66.61, c = 84.90 A, beta = 111.29 degrees ) are significantly improved by covalent modification of the protein with ethylmercury.

Soluble adenylyl cyclase as an evolutionarily conserved bicarbonate sensor

Spermatozoa undergo a poorly understood activation process induced by bicarbonate and mediated by cyclic adenosine 3',5'-monophosphate (cAMP). It has been assumed that bicarbonate mediates its effects through changes in intracellular pH or membrane potential; however, we demonstrate here that bicarbonate directly stimulates mammalian soluble adenylyl cyclase (sAC) activity in vivo and in vitro in a pH-independent manner. sAC is most similar to adenylyl cyclases from cyanobacteria, and bicarbonate regulation of cyclase activity is conserved in these early forms of life. sAC is also expressed in other bicarbonate-responsive tissues, which suggests that bicarbonate regulation of cAMP signaling plays a fundamental role in many biological systems.

Cannabinoids protect cells from oxidative cell death: a receptor-independent mechanism

Serum is required for the survival and growth of most animal cells. In serum-free medium, B lymphoblastoid cells and fibroblasts die after 2 days. We report that submicromolar concentrations of Delta(9)-tetrahydrocannabinol (THC), Delta(8)-THC, cannabinol, or cannabidiol, but not WIN 55,212-2, prevented serum-deprived cell death. Delta(9)-THC also synergized with platelet-derived growth factor in activating resting NIH 3T3 fibroblasts. The cannabinoids' growth supportive effect did not correlate with their ability to bind to known cannabinoid receptors and showed no stereoselectivity, suggesting a nonreceptor-mediated pathway. Direct measurement of oxidative stress revealed that cannabinoids prevented serum-deprived cell death by antioxidation. The antioxidative property of cannabinoids was confirmed by their ability to antagonize oxidative stress and consequent cell death induced by the retinoid anhydroretinol. Therefore, cannabinoids act as antioxidants to modulate cell survival and growth of B lymphocytes and fibroblasts.

[Actinomycosis of the pelvis with an indwelling IUD]

Infection with actinomycosis israeli (an anaerobic, gram-positive bacterium) presents as chronic inflammation with tendency to fibrosis and suppuration with formation of external sinuses. Cervicofacial, thoracic and abdominal forms of the disease made up 95% of cases of actinomycosis. A 53-year-old woman was admitted to the hospital because of a pelvic mass which was thought to be malignant. A laparotomy was performed and the histologic examination showed actinomycosis. The patient first received penicillin followed by tetracyclin and the pelvic mass shrunk. One year later no more mass was detectable. We think that the IUP in place over years is the source for this infection.

Specific expression of soluble adenylyl cyclase in male germ cells

The cAMP signaling pathway is an important mediator of extracellular signals in organisms from prokaryotes to higher eukaryotes. In mammals two types of adenylyl cyclase synthesize cAMP; a ubiquitous family of transmembrane isoforms regulated by G proteins in response to extracellular signals, and a recently isolated soluble enzyme insensitive to heterotrimeric G protein modulation. Using the very sensitive reverse transcription-polymerase chain reaction (RT-PCR), soluble adenylyl cyclase (sAC) expression is detectable in almost all tissues examined; however, Northern analysis and in situ hybridization indicate that high levels of sAC message are unique to male germ cells. Elevated levels of sAC mRNA are first observed in pachytene spermatocytes and expression increases through spermiogenesis. The accumulation of high levels of message in round spermatids suggests sAC protein plays an important role in the generation of cAMP in spermatozoa, implying possible roles in sperm maturation through the epididymis, capacitation, hypermotility, and/or the acrosome reaction.

Vincristine treatment revealing asymptomatic hereditary motor sensory neuropathy type 1A

A 5 year old boy developed severe weakness after receiving vincristine for treatment of acute lymphoblastic leukaemia. Although weakness improved after the discontinuation of vincristine, other symptoms suggestive of a neuropathy persisted. Neurophysiological and genetic analysis at age 8 years indicated that vincristine had induced symptoms of a hereditary sensory motor neuropathy type 1A, which had previously been asymptomatic; his genetically affected mother was also asymptomatic.

Anhydroretinol induces oxidative stress and cell death

The retro-retinoid anhydroretinol (AR), a physiological metabolite of retinol (vitamin A), induces cell death in multiple in vitro systems. AR-induced cell death is blocked by retinol and its metabolite 14-hydroxy-4,14-retro-retinol. AR has been shown also to prevent mammary cancer induced by N-methyl-N-nitrosourea in rats. We report that AR kills cells by generating reactive oxygen species. Direct measurements show that the addition of AR to lymphoblastoid cells increases the intracellular oxidative stress in a time- and dose-dependent manner. Furthermore, the amount of induced oxidative stress directly correlates with the number of dying cells. The addition of retinol, 14-hydroxy-4,14-retro-retinol, or the antioxidant, alpha-tocopherol (vitamin E), decreases AR-induced oxidative stress and proportionally reduces AR-induced cell death. In contrast, pretreatment with caspase inhibitors, known to inhibit apoptosis, has no effect on AR-induced cell death. This is the first demonstration of cellular reactive oxygen species production by a natural retinoid.

Cytosolic adenylyl cyclase defines a unique signaling molecule in mammals

Mammals have nine differentially regulated isoforms of G protein-responsive transmembrane-spanning adenylyl cyclases. We now describe the existence of a distinct class of mammalian adenylyl cyclase that is soluble and insensitive to G protein or Forskolin regulation. Northern analysis indicates the gene encoding soluble adenylyl cyclase (sAC) is preferentially expressed in testis. As purified from rat testis cytosol, the active form of sAC appears to be a fragment derived from the full-length protein, suggesting a proteolytic mechanism for sAC activation. The two presumptive catalytic domains of sAC are closely related to cyanobacterial adenylyl cyclases, providing an evolutionary link between bacterial and mammalian signaling molecules.