Short- and long-term effects of fire and vegetation cover on four lizard species in Amazonian savannas

Ecological succession in tropical savannas is limited by seasonal fire, which affects habitat quality. Although fire may cause negligible or positive effects on animals occupying savannas, most short-term studies (months to a few years) are based on a single temporal sampling snapshot, and long-term studies (decades) are rare. We sampled four lizard species (Rainbow Whiptail, Cnemidophorus lemniscatus (Linnaeus, 1758); Striped Whiptail, Kentropyx striata (Daudin, 1802); Grass Anole, Norops auratus Duméril and Bibron, 1837 = Anolis auratus Daudin, 1802; Amazon Racerunner, Ameiva ameiva (Linnaeus, 1758)) in Amazonian savannas to test the effects of fire and vegetation cover on lizard densities at two temporal scales. In the short term, we use three sampling snapshots to test the effects of fire and vegetation cover on estimated lizard densities over the subsequent 1–5 years. In the long term, we test the effects of fire and changes in vegetation cover over 21 years on current lizard density differences. In the short term, species responses were usually consistent with foraging and thermoregulation modes. However, the results were not consistent among species and years, although the variances in species density explained by year as a random factor were generally low. In the long term, the main effects of fire and vegetation cover show that lizard densities may change spatially, but not necessarily temporarily. Wildfire is a natural resource of savannas and apparently have little impact on resident lizards of that ecosystem.

Determining the Efficacy of a Hybridizing Agent in Wheat (Triticum aestivum L.)

Hybrid wheat (Triticum spp.) has the potential to boost yields and enhance production under changing climates to feed the growing global population. Production of hybrid wheat seed relies on male sterility, the blocking of pollen production, to prevent self-pollination. One method of preventing self-pollination in the female plants is to apply a chemical hybridizing agent (CHA). However, some combinations of CHA and genotypes have lower levels of sterility, resulting in decreased hybrid purity. Differences in CHA efficacy are a challenge in producing hybrid wheat lines for commercial and experimental use. Our primary research questions were to estimate the levels of sterility for wheat genotypes treated with a CHA and determine the best way to analyze differences. We applied the CHA sintofen (1-(4-chlorphyl)-1,4-dihydro-5-(2-methoxyethoxy)-4-oxocinnoline-3-carboxylic acid; Croisor 100) to 27 genotypes in replicate. After spraying, we counted seed in bagged female heads to evaluate CHA efficacy and CHA-by-genotype interaction. Using logit and probit models with a threshold of 7 seeds, we found differences among genotypes in 2015. Sterility was higher in 2016 and fewer genotypic differences were found. When CHA-induced sterilization is less uniform as in 2015, zero-inflated and hurdle count models were superior to standard mixed models. These models calculate mean seed number and fit data with limit-bounded scales collected by agronomists and plant breeders to compare genotypic differences. These analyses can assist in selecting parents and identifying where additional optimization of CHA application needs to occur. There is little work in the literature examining the relationship between CHAs and genotypes, making this work fundamental to the future of hybrid wheat breeding.

A novel QTL associated with dwarf bunt resistance in Idaho 444 winter wheat

KEY MESSAGE

A novel QTL, Q.DB.ui-7DS, and the PCR-based markers identified in the current study will accelerate variety development for resistance to dwarf and common bunt of wheat. Dwarf bunt [Tilletia controversa J.G. Kühn [as 'contraversa'], in Rabenhorst, Hedwigia 13: 188 (1874)] is a destructive disease of wheat (Triticum aestivum L.) that reduces grain yield and quality. A number of distinct genes conferring resistance to dwarf bunt have been used by breeding programs for nearly 100 years. However, few markers were identified that can be used in selection of dwarf bunt resistance. A recombinant inbred line (RIL) population derived from the bunt-resistant germplasm, Idaho 444 (IDO444), and the susceptible cultivar, Rio Blanco, was evaluated for phenotypic reaction to dwarf bunt inoculation in four trials in two locations (USU and USDA) over 3 years. The population was genotyped with the Diversity Arrays Technology (DArT) and the Illumina Infinium 9K iSelect marker platforms. A total of three QTL were detected, and resistant alleles were from IDO444. QTL Q.DB.ui-7DS on 7DS was determined based on the location of a DArT marker wPt-2565 (X116197), which was consistently detected and explained 32 to 56 % of phenotypic variation among the four trials. QTL Q.DB.ui-1A on 1A was detected in three Utah State University (USU) trials and explained 11-15 % of phenotypic variation. QTL Q.DB.ui-2B on 2B was detected in two USU and one United States Department of Agriculture (USDA) trials and explained up to 6 % of phenotypic variation. Two PCR-based markers were developed based on the sequence of wPt-2565 and validated in the RIL population and used in genotyping of dwarf bunt differential lines, known resistance sources, and resistant cultivars.

Identification of milling and baking quality QTL in multiple soft wheat mapping populations

Two mapping approaches were use to identify and validate milling and baking quality QTL in soft wheat. Two LG were consistently found important for multiple traits and we recommend the use marker-assisted selection on specific markers reported here. Wheat-derived food products require a range of characteristics. Identification and understanding of the genetic components controlling end-use quality of wheat is important for crop improvement. We assessed the underlying genetics controlling specific milling and baking quality parameters of soft wheat including flour yield, softness equivalent, flour protein, sucrose, sodium carbonate, water absorption and lactic acid, solvent retention capacities in a diversity panel and five bi-parental mapping populations. The populations were genotyped with SSR and DArT markers, with markers specific for the 1BL.1RS translocation and sucrose synthase gene. Association analysis and composite interval mapping were performed to identify quantitative trait loci (QTL). High heritability was observed for each of the traits evaluated, trait correlations were consistent over populations, and transgressive segregants were common in all bi-parental populations. A total of 26 regions were identified as potential QTL in the diversity panel and 74 QTL were identified across all five bi-parental mapping populations. Collinearity of QTL from chromosomes 1B and 2B was observed across mapping populations and was consistent with results from the association analysis in the diversity panel. Multiple regression analysis showed the importance of the two 1B and 2B regions and marker-assisted selection for the favorable alleles at these regions should improve quality.

Renal transplantation in lupus nephritis: a Brazilian cohort

OBJECTIVE

To determine the epidemiological profile and outcome of patients with lupus nephritis (LN) undergoing renal transplantation.

METHODS

The archival records of 50 patients with LN and end-stage renal disease (ESRD) treated by kidney transplantation from March 1992 to December 2010 were reviewed. All patients met the American College of Rheumatology criteria for systemic lupus erythematosus (SLE).

RESULTS

Fourteen patients were included in the study. The majority were women (85.7%) and non-Caucasian (85.7%); the mean age at diagnosis of SLE and LN was 24 ± 8 and 25 ± 8 years, respectively. Renal biopsy was performed in 12 patients, with 75% of them showing proliferative lesions (class III and IV according to the World Health Organization and International Society of Nephrology/Renal Pathology Society classification). Thirteen patients (93%) underwent intermittent hemodialysis or peritoneal dialysis before transplantation. The median time between the start of dialysis and transplantation was 30 months (range 3-103 months); 67% of the procedures involved deceased donors and 33% involved living-related donors. The graft survival rates were 93.3%, 90.9%, and 85.7% at 1, 5 and 10 years, respectively. Post-transplant immunosuppressive agents were mycophenolate mofetil (84%), azathioprine (17%), tacrolimus (25%), sirolimus (58%) and cyclosporine (8%). Eight episodes of acute rejection were noted in six patients. There was a graft loss due to renal vein thrombosis in the one patient with secondary antiphospholipid syndrome. The mean SLICC by the time of kidney transplantation was 5 ± 2. In total, 13 patients (92.8%) developed at least one infectious event during the follow-up, with one dying in the immediate post-transplant period because of sepsis. Two patients (14%) had a lupus flare. There was no clinical or histological evidence of LN recurrence.

CONCLUSION

LN is the major cause of morbidity in SLE, with progression to ESRD in 10-22% of cases. Despite concerns about LN recurrence after renal transplantation, the data obtained in our sample indicate this procedure as a safe alternative therapy for ESRD in this population.

Estudo da retenção de íons cromo por gibbsita e peneira molecular

Neste trabalho, relatamos o emprego de gibbsita e de uma peneira molecular comercial para a retenção de íons cromo. Os estudos envolveram, além destes materiais, soluções com diferentes concentrações do íon e variações na concentração e na temperatura das soluções e, também, do tempo de contato entre essas e as fases estacionárias. Os resultados desses experimentos e dos posteriores processos de lixiviação do íon indicam que tanto a gibbsita quanto a peneira molecular são materiais que apresentam alta capacidade de retenção deste íon e, além disso, são altamente resistentes aos processos de lixiviação.

Barley (Hordeum vulgare L.) inositol monophosphatase: gene structure and enzyme characteristics

The cellular myo-inositol (Ins) pool is important to many metabolic and signaling pathways in plants. Ins monophosphatase (IMPase; EC 3.1.3.25) activity is essential for the de novo synthesis of myo-Inositol (Ins), and for recycling of Ins in Ins(1,4,5)P3. However, proteins encoded by at least one family of IMP genes also have L-galactose-1-P phosphatase activity important to ascorbic acid synthesis, indicating a bifunctionality that links these two branches of carbon metabolism. As part of research into the regulation of Ins synthesis and supply during seed development, the barley IMP-1 gene and gene products were studied. The 1.4 kb barley IMP-1 promoter contains one low temperature response element (RE), two heat shock REs, one gibberellin and two auxin REs, and five sugar REs. Barley IMP-1 is expressed in all tissues assayed, and expression levels were not greatly altered by abiotic stress treatments. Reduced use of Ins for Ins P6 synthesis in developing seed of barley low phytic acid (lpa) mutants results in Ins accumulation, and IMP-1 expression is reduced in proportion to the increase in Ins level. The barley recombinant enzyme had a lower Km, indicating higher affinity, for D/L-Ins(3)P1 (Km = 9.7 microM) as compared with reported Km (Ins P1) values for other eukaryotic IMPases (43-330 microM) or with a reported Km (L-Gal-1P) of 150 microM for a kiwifruit (Actinidia deliciosa) enzyme. These and other data indicate that the barley IMP-1 gene is regulated at least in part in response to Ins metabolic needs, and that the enzyme it encodes displays catalytic properties well suited for a role in Ins synthesis, in addition to other roles as an L-gal-1-P phosphatase important to ascorbate synthesis, or as an IMPase important to Ins(1,4,5)P3 signal recycling.

Weight Gain Post–Renal Transplantation and Its Association With Glomerular Filtration Rate

OBJECTIVE

Obesity may be a risk factor for renal graft loss. The purpose of this study was to assess weight gain and its association with glomerular filtration rate after kidney transplant.

METHODS

This retrospective analysis of 152 adult renal transplant outpatients (77 males, 75 females; mean age, 45.6 +/- 10.1 years) with at least 6 months posttransplantation (post-tx) included body weight and creatinine clearance (CrCl) measured pretransplantation (pre-tx) as well as at 6 months (post-tx1), 1 year (post-tx2), 5 years (post-tx3), 10 years (post-tx4), 15 years (post-tx5), and 20 years (post-tx6) post-tx. Weight gain was determined by subtracting patient preoperative weight from the post-tx weights.

RESULTS

The weight gain post-tx versus pre-tx was progressive and significant (P < .001) post-tx1, 8.7 +/- 10.9% (n = 152); post-tx2, 12.4 +/- 11.5% (n = 150); post-tx3, 16.6 +/- 14.8% (n = 102); post-tx4, 20.1 +/- 18.1% (n = 47); post-tx5, 20.8 +/- 19.8% (n = 17); and post-tx6, 21.0 +/- 32.5% (n = 11). There was a positive and significant correlation between weight gain and CrCl during most times post-tx: post-tx2 (r = 0.32; P < .000); post-tx3 (r = 0.54; P < .0001); post-tx4 (r = 0.47; P = .01); and post-tx6 (r = 0.92; P < .001).

CONCLUSIONS

There was a great increase in body weight after kidney transplantation. The excessive body weight gain was associated with a better glomerular filtration rate.

Prevalence of Risk Factors for Cardiovascular Disease in Brazilian Renal Transplant Recipients

OBJECTIVE

Cardiovascular disease (CVD) is the major cause of death in renal transplant recipients. The aim of this study was to assess the prevalence of CVD risk factors among Brazilian adult renal transplant recipients.

METHODS

This cross-sectional study included 192 cases in which the evaluated CVD risk factors were hypertension, diabetes mellitus, impaired fasting glucose, obesity, overweight, abdominal obesity, metabolic syndrome, and dyslipidemia.

RESULTS

Hypertension, abdominal obesity, and hypercholesterolemia were the highest prevalent risk factors among the total population with prevalences of approximately 60%. The prevalence of obesity was significantly higher (P < .001) in recipients with normal graft function (28%) than in those with impaired graft function (7%). Abdominal obesity was also higher (P = .02) in the normal graft function group (77%) than in recipients with creatinine clearance (CrCl) values <60 mL/min (61%). There were positive, significant correlations between CrCl and body mass index (BMI) (r = 0.47; P < .001) and between CrCl and waist circumference (WC) (r = 0.44; P < .001). BMI (r = 0.31; P < .001) and WC (r = 0.27; P < .001) were also positively associated with triglyceride levels. There were negative associations of high-density lipoprotein (HDL)-cholesterol (HDL-c) with BMI (r = -0.28; P < .01) and WC (r = -0.32; P < .01).

CONCLUSIONS

The high prevalence of CVD risk factors among renal transplant recipients emphasizes the importance of taking appropriate therapeutic measures to reduce modifiable risk factors, reducing CVD and its consequences.

Origin and diversity of North American hard spring wheats

Genetic diversity is an important safeguard against crop vulnerability to biotic and abiotic stresses. Coefficient-of-parentage (COP) values of 248 North American hard spring wheat (Triticum aestivum L. em. Thell) cultivars released from 1901 to 1991 were used to estimate the genetic similarity of cultivars. COP values were used: to (1) quantify germ plasm sources and their contributions to the North American hard spring wheat gene pool; (2) measure changes in genetic diversity through time; and (3) identify major groupings of related cultivars. Landraces and local cultivars that contributed to the formation of the gene pool were: spring wheat (64%), winter wheat (16%), T. turgidum var. durum L. (10%), and T. turgidum var. emmer L. (8%). 'Fife', 'Hard Red Calcutta', and 'Turkey Red' accounted for 18%, 13%, and 8%, respectively, of the hard spring wheat origins. 'Era' and 'Butte' in the US, and 'Neepawa' and 'HY 320' in Canada, were the most commonly used named parents of cultivars released from 1981 to 1991. Both Canada and US had the greatest level of similarity among new cultivar releases in the 1930s (Canada: r=0.39, US: r=0.34). Genetic similarity in the US declined to r=0.14 in the 1940s and remained relatively constant thereafter. Similarity among released Canadian cultivars remained relatively high until the 1970s when the introduction of new market classes resulted in a 50% reduction in genetic similarity to approximately the same level of similarity found in the US. Cluster analysis was used to group cultivars released after 1941 into 13 clusters of similar genotypes. The cultivar clusters may have value for the stratified sampling of spring wheat germ plasm or in identifying diverse germ plasm for intermating.

Prediction of progeny variation in oat from parental genetic relationships

The ability to predict agronomic performance of progeny from a cross would be a great benefit to plant breeders in selecting parents. The predictive value of parental genetic relationships estimating F1 progeny means and F4 family variances of nine argronomic traits was tested in 76 oat crosses, using genetic distance measures based on coefficients-of-parentage, quantitatively inherited morphological characters, and discretely inherited biochemical and morphological characters. Coefficients-of-parentage were better predictors of F1 performance than similarity measures derived from plant morphology or discretely inherited characters. Combined distance measures were better estimators of F1 specific combining ability (SCA) effects than any single measure. Among cultivars of similar adaptation and quantitative morphology, crosses between parents with high coefficients-of-parentage gave higher SCA effect values than crosses of distantly related parents for grain yield and total biomass. The opposite was found for crosses among cultivars of different adaptation or quantitative morphology. The best predictor of trait variances among F4 families was coefficients-of-parentage. Crosses between more distantly related parents produced larger variances among families than crosses between closely related parents for plant biomass. For grain yield, test weight, heading date, grain filling period, and maturity date, crosses between more closely related parents produced larger among-family variances than crosses of distantly related parents. Crosses between more distantly related parents involved at least one parent unadapted to central New York, and resulted in most of the progeny being generally unadapted. This, in part, may account for the low genetic variances for heading date, test weight, and grain yield in crosses of distantly related parents.

Inheritance and distribution of variation at four avenin loci in North American oat germ plasm

Avenins (prolamines of the Avena genus) have been shown to be useful in taxonomic studies and cultivar identification; specific allelic identification could assist in these types of studies as well as providing a basis for future linkage and gene mapping studies. The avenin patterns produced by nondenaturing polyacrylamide gel electrophoresis were compared in 70 North American oat cultivars and germ plasms. Populations of F2 progeny were subsequently evaluated to test for allelism of proteins found to be noncoincident in the survey of homozygous cultivars. A minimum of four loci (Av1, Av2, Av3, and Av4) were found to possess alternate alleles with distinctive electrophoretic mobilities. Segregation of 10 alternate alleles were observed in studies of F2 progeny: four for Av1, and two each for the other three loci. Additional variation found among the surveyed cultivars suggested at least two additional electrophoretically variant polypeptides. Several of the alleles were found to be associated with cultivars from specific geographic regions. Two examples were (i) the near exclusive association of the Av10.76 allele with Canadian cultivars and (ii) the high association of the Av10.58 allele with fall-planted cultivars. Fifty percent (SE ± 10.7%) of the fall-planted cultivars have the Av40.58 allele compared with 27.1% (SE ± 8.8%) of spring-planted cultivars.Key words: avenins, prolamines, polyacrylamide gel electrophoresis, linkage.

Sequential studies of glucose tolerance and red blood cell insulin receptors in normal human pregnancy

Insulin binding to erythrocytes was sequentially studied in 12 healthy pregnant women during the anabolic (11-22 wk) and the catabolic (31-38 wk) gestational phases. For comparison, we studied 12 nonpregnant subjects at mid-luteal and mid-follicular menstrual phases. Oral glucose tolerance tests were also performed during these studies. There was a progressive worsening of the glucose tolerance from the anabolic to the catabolic phase associated with fasting hypoglycemia and hyperinsulinemia. The worsening of glucose tolerance was accompanied by a progressive increment of insulin secretion. Insulin binding to red blood cells increased progressively from the anabolic to the catabolic phase, due to an increased number of receptors per cell, associated with a reduction in the apparent affinity at the low occupancy levels. We concluded that the insulin resistance of pregnancy was not accompanied by an impaired binding of insulin to its receptors, at least in the RBC. The data suggest that the defect of insulin action lies at a site distal to the receptor.

Drinking patterns in experimental and barroom settings

A discount drink policy ("happy hour") was related to increases in the frequency of drinking and amounts of alcohol consumed by casual and heavy drinkers in experimental and barroom settings.