Breeding oat for resistance to the crown rust pathogen Puccinia coronata f. sp. avenae: achievements and prospects.

Crown rust, caused by Puccinia coronata f. sp. avenae (Pca), is a significant impediment to global oat production. Some 98 alleles at 92 loci conferring resistance to Pca in Avena have been designated; however, allelic relationships and chromosomal locations of many of these are unknown. Long-term monitoring of Pca in Australia, North America and elsewhere has shown that it is highly variable even in the absence of sexual recombination, likely due to large pathogen populations that cycle between wild oat communities and oat crops. Efforts to develop cultivars with genetic resistance to Pca began in the 1950s. Based almost solely on all all-stage resistance, this has had temporary benefits but very limited success. The inability to eradicate wild oats, and their common occurrence in many oat growing regions, means that future strategies to control Pca must be based on the assumption of a large and variable prevailing pathogen population with high evolutionary potential, even if cultivars with durable resistance are deployed and grown widely. The presence of minor gene, additive APR to Pca in hexaploid oat germplasm opens the possibility of pyramiding several such genes to give high levels of resistance. The recent availability of reference genomes for diploid and hexaploid oat will undoubtedly accelerate efforts to discover, characterise and develop high throughput diagnostic markers to introgress and pyramid resistance to Pca in high yielding adapted oat germplasm.

Long-term outcome of liver transplantation in childhood: A study of 20-year survivors.

We report the results of a study of survival, liver and kidney functions, and growth with a median follow-up of 24 years following liver transplantation in childhood. From 1988 to 1993, 128 children underwent deceased donor liver transplantation (median age: 2.5 years). Twenty-year patient and graft survival rates were 79% and 64%, respectively. Raised serum aminotransferase and/or γ-glutamyl transferase activities were present in 42% of survivors after a single transplantation. Graft histology (35 patients) showed signs of chronic rejection in 11 and biliary obstruction in 5. Mean total fibrosis scores were 4.5/9 and 3/9 in patients with abnormal and normal serum liver tests, respectively. Glomerular filtration rate was <90 mL·min-1 in 35 survivors, including 4 in end-stage renal disease who were undergoing dialysis or had undergone renal transplantation. Median final heights were 159 cm for women and 172 cm for men; final height was below the target height in 37 patients. Twenty-year survival after childhood liver transplantation may be close to 80%, and final height is within the normal range for most patients. However, chronic kidney disease or altered liver biochemistries are present in over one third of patients, which is a matter of concern for the future.

Comparative analyses of ion release, pH and multispecies biofilm formation between conventional and bioactive gutta-percha.

AIM: To analyse the effect of commercial and experimental gutta-percha with the addition of niobium phosphate glass on biofilm formation by oral bacteria from human dental plaque. Additional pH and elemental release of the materials were analysed. METHODOLOGY: The multispecies biofilm was grown anaerobically from plaque bacteria on standardized discs of each material: hydroxyapatite (HA), gutta-percha pellets (OBT) (Obtura pellets, Shoreline, CT, USA), ProTaper gutta-percha (PTP) (ProTaper Universal Gutta-Percha Points, Dentsply Maillefer, Ballaigues, Switzerland), EndoSequence BC gutta-percha (GBC) (Brasseler USA, Savannah, GA, USA), experimental gutta-percha associated with niobium phosphate glass (GNB) and niobium phosphate glass (NPG). Specimens (n = 5 per group and per incubation period) were incubated in brain-heart infusion broth for 3, 14 and 30 days, at 37 °C, and stained using live/dead viability assay. Images were analysed by confocal laser scanning microscopy (CLSM) and the total biovolume (mm3 ), viable bacteria biovolume (mm3 ), and live percentage (%) were quantified. For pH measurement, specimens of each material (n = 3) were immersed in phosphate-buffered saline at 37 °C, and pH was monitored in multiple intervals, up to 30 days. For elemental analysis, additional specimens (n = 3) were immersed in deionized water and elemental release was analysed by ICP-OES (inductively coupled plasma - optical emission spectrometry) at time intervals of 3, 14 and 30 days. Differences between groups were evaluated by the two-way analysis of variation (anova) with Tukey's post hoc test (P < 0.05). RESULTS: The lowest total biovolume at 30 days was found in GNB, GBC and NPG. GNB had the lowest viable bacteria biovolume (mean value) at 30 days (P < 0.05), and the lowest live percentage of bacteria at 3 and 30 days (P < 0.05), whilst NPG had the lowest live percentage at 14 days (P < 0.05). GNB had the highest pH (8.45) after 30 days (P < 0.05), and the greatest Zn and Na release at all time intervals (P < 0.05). Both GBC and GNB had significantly higher Ca release at 14 and 30 days. CONCLUSION: GNB and GBC reduced biofilm formation, GNB had the lowest amount of viable bacteria in biofilms with the highest pH, and high Zn and Na release values after 30 days.

Micropush-out dentine bond strength of a new gutta-percha and niobium phosphate glass composite.

AIM: To characterize an experimental gutta-percha and niobium phosphate glass composite (GNB) applied with a thermoplastic technique to the root canals without sealer in a moist environment and to evaluate its micropush-out bond strength to root canal wall dentine. METHODOLOGY: The root canals of sixty human mandibular pre-molars were prepared using rotary NiTi instruments and irrigation with sodium hypochlorite and EDTA. The teeth were then randomly divided into three groups according to the root filling material used: AH plus sealer and gutta-percha (AH), EndoSequence BC gutta-percha without sealer (GBC), and GNB without sealer. The root canals were filled with a single cone using warm vertical condensation. Push-out bond strengths associated with the filling materials in slices from middle root thirds was determined 30 days after root filling. The failure mode was analyzed with SEM. Analysis using EDX and SEM-EDS was carried out to verify the composition and distribution of the particles of the tested materials. Data were statistically analyzed by one-way anova and Tukey's test (P < 0.05). RESULTS: AH and GNB groups had bond strengths of 2.83 ± 0.64 MPa and 2.68 ± 0.84 MPa, respectively, with no significant difference between them (P > 0.05). The GBC group had the lowest mean bond strength (1.34 ± 0.42 MPa), which was significantly different compared with the other groups (P < 0.05). Cohesive failures prevailed in the AH group, whereas failures were mixed in the GBC and GNB groups. The SEM-EDS analysis on the surface and in the bulk of GBC revealed only a superficial coating of bioceramic particles. Glass particles were detected both on the surface and in the bulk of GNB. CONCLUSIONS: The experimental root filling composite (GNB) had an ability to adhere to root canal wall dentine equal to the current gold standard root filling with gutta-percha and sealer (AH Plus).

Exerting pulling forces in fluids by directional disassembly of microcrystalline fibres.

Biomolecular polymerization motors are biochemical systems that use supramolecular (de-)polymerization to convert chemical potential into useful mechanical work. With the intent to explore new chemomechanical transduction strategies, here we show a synthetic molecular system that can generate forces via the controlled disassembly of self-organized molecules in a crystal lattice, as they are freely suspended in a fluid. An amphiphilic monomer self-assembles into rigid, high-aspect-ratio microcrystalline fibres. The assembly process is regulated by a coumarin-based pH switching motif. The microfibre crystal morphology determines the monomer reactivity at the interface, resulting in anisotropic etching. This effect exerts a directional pulling force on microscopic beads adsorbed on the crystal surface through weak multivalent interactions. We use optical-tweezers-based force spectroscopy to extract mechanistic insights into this process, quantifying a stall force of 2.3 pN (±0.1 pN) exerted by the ratcheting mechanism produced by the disassembly of the microfibres.

Prediction of Death with the FRAIL-NH in Institutionalized Older Adults: A Longitudinal Study from a Middle-Income Country.

BACKGROUND/OBJECTIVES: Frailty is common in nursing homes. However, few studies reported longitudinal validation for death prediction or cut-off scores with the FRAIL-NH, which is designed to be used in nursing homes. Moreover, no studies came from Latin America, where frailty is highly prevalent. Our objectives were to evaluate (1) the prevalence of frailty according to the FRAIL-NH scale, and (2) its association to and the best cut-off score for predicting death after 12 months. DESIGN: longitudinal study with 12-month follow-up. SETTING: 6 nursing homes in southwest of Brazil. PARTICIPANTS: 293 residents with 60 years old or more. METHODS: Frailty was evaluated through the FRAIL-NH scale. Logistic regression was used to estimate the associated between frailty and mortality adjusted for age and sex. ROC curve was used to evaluate the accuracy of the scale for mortality prediction. RESULTS: Frailty was prevalent (47.4%) and was associated with death (odds ratio=1.31, 95% confidence interval [CI]=1.18-1.48, p<0.001). The area under the curve was 0.741 (95%CI=0.68-0.79). The sensitivity and specificity of the FRAIL-NH scale according to the best value of the Youden Index was 72.9% and 66.5%, respectively, for a cut-off > 8 points. CONCLUSIONS: Frailty is prevalent in nursing homes according to the FRAIL-NH and it was associated with one-year prediction of death for a cut-off > 8 points.

Participant centred safety surveillance of health care workers receiving influenza vaccination.

Following the introduction of mandatory influenza vaccination for staff working in high risk clinical areas in 2018, we conducted active surveillance for adverse events following immunisation utilising an automated online survey to vaccine recipients at three and 42 days post immunisation. Most participants 2285 (92%) agreed to participate; 515 (32%) staff reported any symptom and eight (1.6%) sought medical attention. The odds of having a reaction decreased with age by approximately 2% per year. The system was acceptable to staff, and the data demonstrated rates of reported symptoms within expected rates for influenza vaccines from clinical trials. Rates of medical attendance were similar to previous surveillance. Participant centred real-time safety surveillance proved useful in this staff influenza vaccination context, providing reassurance with expected rates and profile of common adverse events following staff influenza vaccination.

Frailty Could Predict Death in Older Adults after Admissionat Emergency Department? A 6-month Prospective Study from a Middle-Income Country.

BACKGROUND: The number of older adults attending emergency department (ED) is increasing all over the world. Usually, those patients are potentially more complex due to their greater number of comorbidities, cognitive disorders, and functional or physical disabilities. Frailty is a vulnerable state that could predict adverse outcomes of those patients. There are very few studies that addressed this topic in the ED, and none of them used a simple instrument for frailty assessment. OBJECTIVES: The primary outcome was to evaluate the association between frailty identified through the FRAIL questionnaire at baseline and death after a 6-month follow-up period after hospital discharge from the ED. Secondary outcomes were readmission to the ED and disability after 6 months. METHODS: A 6-month follow-up prospective study (FASES study) was conducted at a university-based trauma-center ED in Jundiaí, southwestern of Brazil. A total of 316 older adults aged 60 or older were randomly included based on a lottery of their medical record admission number. Frailty was evaluated through the FRAIL questionnaire. The association between frailty and death was estimated through a binary logistic regression adjusted for age, sex, and cognitive performance. RESULTS: From the total sample, the mean age was 72.11±8.0 years, and 51.6% were women. Participants presented 2.28±1.4 comorbidities and 25.6% were frail. Mean hospital stay was 5.43±5.6 days. Death occurred in 52 participants, readmission to the emergency in 55, and new disability in 16 after 6 months. Frailty was associated with an odds ratio of 2.18 for death after 6 months (95% CI = 1.10-4.31; p = 0.024). This association lost significance after multivariate analysis taking into account cognitive performance. There was no association between frailty status at baseline and readmission to the ED or disability. CONCLUSION: The identification of frailty using the FRAIL at admission was not predictive of death after a 6-month period after discharge from the ED. Simple frailty assessment could identify patients at higher risk for death in the follow-up.

Polypharmacy but not Potential Inappropriate Prescription Was Associated with Frailty in Older Adults from a Middle-Income Country Outpatient Clinic.

OBJECTIVES: the aims of the present study were: (1) investigate the prevalence and association of polypharmacy and pre-frailty or frailty in a middle-income country sample of older adults; and (2) evaluate the prevalence of potential inappropriate prescription (PIP) and its association with pre-frailty or frailty. DESIGN: Cross-sectional observational study. SETTING: Outpatient center at a university-based hospital in the state of São Paulo, Brazil. PARTICIPANTS: 629 older adults from both sexes evaluated between June 2014 and July 2016. MEASUREMENTS: Frailty was identified through the FRAIL scale. All medications received were analyzed by research staff. Presence of PIP was evaluated according to the 2015 updated Beers list. Binary logistic regression tested the association between 4 definitions of polypharmacy (≥ 3, 4, 5, and 6 drugs), and presence of PIP, and the dependent variable pre-frailty and frailty. RESULTS: 15.7% of participants were frail. Polypharmacy was present in 219 (34.8%), and PIP was observed in 184 (29.3%) older adults. All definitions of polypharmacy were significantly associated with frailty (OR between 2.05 to 2.34, p < 0.001). Polypharmacy with 4 or 5 or more drugs were associated with pre-frailty (OR 1.53 and 1.47, respectively). PIP was not associated with frailty (OR 1.47, p = 0.149). CONCLUSIONS: Several definitions of polypharmacy were associated with frailty, but only two were associated with pre-frailty. The presence of PIP was not associated with pre-frailty or frailty.

Virulence of Oat Crown Rust in Brazil and Uruguay.

Race-specific resistance to crown rust, the most important disease of oat (Avena sativa) in Bra-zil, often fails within a few years of use in Brazilian cultivars. Virulence of 144 isolates of Puccinia coronata from cultivated oat in Brazil in 1997 to 1999 and 36 isolates from Uruguay in 1994-95 and 1998 was tested on a set of 27 oat crown rust differentials lines, each with a different Pc gene for race-specific resistance. Frequencies of virulence and mean virulence complexity were compared among these five collections from Brazil and Uruguay as well as with mean virulence complexity for a collection of 17 isolates from cultivated oat in western Siberia in Russia. Virulence-avirulence for each of the 27 Pc genes was polymorphic in both Brazil and Uruguay. Virulence frequencies were similar for collections from Brazil in 1998 and 1999 and for the collection from Uruguay from 1998, but there were large differences between the 1997 collection and the 1998 and 1999 collections from Brazil. Mean virulence complexity in both Brazil and Uruguay was greater than reported in the United States and much greater than in the Russian collection of P. coronata. A large number of races of P. coronata were found, with no more than five isolates of any race found in a single year in Brazil or Uruguay. The high virulence complexity and great diversity of virulence polymorphisms in Brazil and Uruguay make it unlikely that race-specific resistance can be effective there even though the South American populations of P. coronata are apparently entirely asexual.

Novel stable dendrimersome formulation for safe bioimaging applications.

Dendrimersomes are nanosized vesicles constituted by amphiphilic Janus dendrimers (JDs), which have been recently proposed as innovative nanocarriers for biomedical applications. Recently, we have demonstrated that dendrimersomes self-assembled from (3,5)12G1-PE-BMPA-G2-(OH)8 dendrimers can be successfully loaded with hydrophilic and amphiphilic imaging contrast agents. Here, we present two newly synthesized low generation isomeric JDs: JDG0G1(3,5) and JDG0G1(3,4). Though less branched than the above-cited dendrimers, they retain the ability to form self-assembled, almost monodisperse vesicular nanoparticles. This contribution reports on the characterization of such nanovesicles loaded with the clinically approved MRI probe Gadoteridol and the comparison with the related nanoparticles assembled from more branched dendrimers. Special emphasis was given to the in vitro stability test of the systems in biologically relevant media, complemented by preliminary in vivo data about blood circulation lifetime collected from healthy mice. The results point to very promising safety and stability profiles of the nanovesicles, in particular for those made of JDG0G1(3,5), whose spontaneous self-organization in water gives rise to a homogeneous suspension. Importantly, the blood lifetimes of these systems are comparable to those of standard liposomes. By virtue of the reported results, the herein presented nanovesicles augur well for future use in a variety of biomedical applications.

Inflammatory changes after cryosurgery-induced necrosis in human melanoma xenografted in nude mice.

There is growing evidence that necrosis, instead of apoptosis, could act as a natural adjuvant, which could activate an immune response. In this work we have investigated if induction of tumor necrosis could trigger the affluence of inflammatory cells at the tumor site, and thus induce an immune response. For this purpose, a liquid N2 spray was applied on human melanoma (IIB-MEL-J cell line) xenografted in nude mice and 24 h later some mice received intratumorally a single 500 U dose of recombinant murine granulocyte macrophage-colony-stimulating factor. 77-100% of the tumor mass underwent necrosis. Congestion, edema, and endothelial cell activation were the first noticeable events. A quick infiltrative response of polymorphonuclear leukocytes around the tumor was detected 24 h after liquid N2 application, peaking at day 3. Massive macrophage recruitment was observed since day 3. An early intratumoral infiltration with inflammatory cells was only detected in the group that received recombinant murine granulocyte macrophage- colony-stimulating factor after necrosis induction by liquid N2. Coexisting DEC 205- and F4/80-positive cells increased in number, and their localization was predominantly peritumoral after necrosis. Antibody response was only detected in the groups with tumor-induced necrosis. Our results suggest that cryosurgery-induced necrosis could be a useful model to analyze the interaction among necrosis, inflammation, and the generation of an immune response.

Synthesis of aza homologues of folic acid.

Folic acid analogues containing an additional nitrogen atom between the phenyl ring and the carbonyl group of the side chain were synthesized. None of the compounds showed significant inhibitory activity against human lymphoblastic leukemia cells (CCRF-CEM) in culture or against Lactobacillus casei (ATCC 7469) growth. Against L1210 leukemia in mice, the aza homologue of folic acid, 4, and the aspartic acid analogue, 14, showed no increase in life span over control animals. These compounds were more toxic in vivo than the corresponding methotrexate analogues. Compound 4 supported the growth of Streptococcus faecium (ATCC 8043), and its tetrahydro derivative supported the growth of Pediococcus cerevisiae (ATCC 8081). These results strongly suggest that 4 can substitute for folate derivatives as cofactors for serine transhydroxymethylase, thymidylate synthetase, and dihydrofolate reductase.

Methotrexate analogues. 9. Synthesis and biological properties of some 8-alkyl-7,8-dihydro analogues.

A series of 8-alkyl-7,8,-dihydromethotrexate analogues was prepared by direct alkylation of 7,8-dihydromethotrexate, after pilot studies were performed with simpler pteridines. These compounds are tested for in vitro inhibitory activity against Lactobacillus casei and as enzyme inhibitors against dihydrofolate reductase and thymidylate synthetase derived from this organism. All of the analogues were less inhibitory toward dihydrofolate reductase than was methotrexate but were more inhibitory toward thymidylate synthetase. The analogues were also evaluated for in vitro inhibitory activity against the CCRF-CEM human lymphoblastic leukemia cells. In vivo against the L-1210 leukemia in mice, several of the analogues exhibited some antileukemic activity.

Methotrexate analogues. 12. Synthesis and biological properties of some aza homologues.

Methotrexate analogues, in which an additional nitrogen atom is inserted between the phenyl ring and the carbonyl group of the side chain, were prepared by photochemical methods. The compounds were less inhibitory toward dihydrofolate reductase and thymidylate synthetase derived from Lactobacillus casei than was methotrexate. They were also less cytotoxic against human lymphoblastic leukemia cells (CCRF-CEM). In vivo against L-1210 leukemia in mice, the aza homologue of methotrexate showed significant antitumor activity (%ILS = 55%) compared to methotrexate (%ILS = 88%).

Hemodynamic performance evaluation of small aortic ATS Medical valves by Doppler echocardiography.

BACKGROUND AND AIMS OF THE STUDY: The ATS Medical valve was first implanted in 1992. The purpose of this report was to establish the normal range of each hemodynamic parameter, measured by Doppler echocardiography, in small aortic ATS Medical valves. METHODS: Twenty-five patients with small aortic ATS Medical valves, operated on over six months, and with no cardiac or prosthetic dysfunction, in sinus rhythm, on adequate oral anticoagulant therapy, and no other valve prosthesis or significant valvulopathy, were reviewed on the basis of physical examination and transthoracic Doppler echocardiography. RESULTS: For the aortic 21 Standard ATS Medical valve (n = 10), the following values were registered: peak velocity 2.40 +/- 0.39 m/s; peak gradient 23.7 +/- 6.8 mmHg; mean gradient 12.6 +/- 4.0 mmHg; valve effective orifice area 1.73 +/- 0.41 cm2; Doppler velocity index 0.47 +/- 0.11. For the aortic 19 Standard ATS Medical valve (n = 9), these values were: 3.41 +/- 0.43 m/s; 47.0 +/- 12.6 mmHg; 26.2 +/- 7.9 mmHg; 0.96 +/- 0.18 cm2; and 0.32 +/- 0.06, respectively. For the aortic 16 AP ATS Medical valve (n = 6), these parameters were 3.44 +/- 0.47 m/s; 47.7 +/- 12.0 mmHg; 27.0 +/- 7.3 mmHg; 0.61 +/- 0.09 cm2; and 0.30 +/- 0.04, respectively. CONCLUSIONS: Using Doppler echocardiography, the present study establishes the normal range of parameters which define the hemodynamic performance of the aortic 21 and 19 Standard and 16 AP ATS Medical valves, and demonstrates satisfactory hemodynamic performance of the aortic 21 and 19 Standard ATS Medical valves. It should be noted that the valve effective orifice area determined for the aortic 16 AP ATS Medical valve was smaller than that for the aortic 19 Standard ATS Medical valve, though these two prostheses have the same physical orifice area.

Descriptive cataloging of serials: the National Library of Medicine versus the Library of Congress.

Descriptive cataloging practices for serial differ significantly in some respects between the Library of Congress and the National Library of Medicine. This paper compares some of these differences and indicates the impact they can have on the development of on-line cooperative data bases such as OCLC. Attention is also given to the possible impact of the second edition of the Anglo-American Cataloguing Rules on serials cataloging. The need for standardization is stressed.