Variation in ecogeographical traits of pecan cultivars and provenances

Pecan [Carya illinoinensis (Wangenh.) C. Koch] is a species distributed over an area of varied geographic and climatic variation in the Unites States and Mexico providing a potential for anatomical and physiological adaptation within the cultivars and provenances (i.e., the area of origin of seed). An assessment of leaf anatomical traits of pecan cultivars (Pawnee, Mohawk and Starking Hardy Giant) collected from three locations (Tifton, GA., Chetopa, KS., and Stillwater, OK.) was conducted to provide an understanding of patterns of ecogeographic variation within the natural range. The stomatal density 'Pawnee’ (404 stomata/mm2) was intermediate between that of ‘Mohawk’ (363 stomata/mm2) and ‘Starking Hardy Giant’ (463 stomata/mm2). There were differences among the three pecan cultivars at the same location but there were no differences in stomatal density within the same cultivar grown at three distinct locations. The study suggested that differences in stomatal density in pecans are cultivar-specific rather than being determined by environmental factors. The stability of certain leaf anatomical characteristics, such as stomatal density, for pecan cultivars grown at different locations confirms that these traits can be used for screening provenances with desirable leaf anatomical characteristics for breeding and cultivar development. To achieve the objective of studying anatomical, morphological and physiological traits, Mexican and U.S. provenances grown at the Pecan Genetics and Breeding Program facility in Somerville, Texas were used. The prominent results from the provenance study indicate the presence of intra-specific variation in pecan provenances for the morphological and anatomical traits along the east-west gradient. It is also interesting to note that western provenances displayed the least stomatal density (350 stomata/mm2) while an eastern provenance showed the greatest stomatal density (728 stomata/mm2). This trend may be explained with the gradient in moisture availability from the wetter conditions in the east to the arid conditions in the west in North America. Most of the physiological traits measured did not show any distinct differences between the provenances. There is a great possibility that anatomical traits like stomatal density are genetically controlled to a great extent in pecan in comparison to the physiological traits

Molecular characterization of genes regulating fumonisin biosynthesis and development in maize pathogen fusarium verticilliodes

Fusarium verticillioides (Sacc.) Nirenberg (teleomorph Gibberella moniliformis Wineland) is a fungal pathogen of maize that causes ear rots and stalk rots worldwide. In addition, it produces a group of mycotoxins called fumonisins when the fungus colonizes maize and maize-based products. Fumonisin B1 (FB1), the predominant form occurring in nature, can cause detrimental health effects in animals and humans. Several efforts were made to study the host and pathogen factors that contribute to the production of fumonisins. Using the available genomic resources, three genes with a potential role in FB1 regulation and development were identified. The genes are GBP1, GBB1 and GAP1. This research describes molecular characterization of these genes with respect to regulation of FB1 and development in F. verticillioides. GBP1 is a monomeric GTP binding protein with similarity to DRG and Obg sub-classes of G-proteins. GBB1 encodes heterotrimeric GTP binding protein β subunit. GAP1 is a GPI (Glycophosphotidylinositol) anchored protein, which belongs to a family of cell wall proteins. Targeted deletion and complementation studies indicated that GBP1 is negatively associated with FB1 biosynthesis but had no effect on conidiation in F. verticillioides. GBB1 plays an important role in regulation of FB1 biosynthesis, conidiation and hyphal growth, but not virulence. GAP1 is associated with growth, development and conidiation but not in positive regulation of FB1 or pathogenicity. The outcome of this study revealed new molecular genetic components that will help scientists better understand signal transduction pathways that regulate FB1 biosynthesis and conidiation in F. verticillioides

Role of technology: Podcast in influencing respondents to receive a flu shot

Background and Problem: Studies have demonstrated that flu shots are an effective method to control flu infection. However, statistics reveal that only about 68% of people get vaccinated in the U.S. every year. We wanted to develop and evaluate an intervention to increase influenza vaccination rate. [See PDF for complete abstract

Factors associated with family carers’ fall concern: Prospective study protocol

Background: Family carers are important in preventing community-dwelling older people from falling. Family carers’ concerns about older people\u27s risk of falling could affect their own physical and psychological health, lifestyle, and burden of care. While there are many studies exploring factors associated with fear of falling among older people, there is no research on family carers’ fall concern of older people (care recipients) who are hospitalised. Aim: This paper describes a prospective study protocol exploring the relationship of fall concern, psychological distress, and quality of life of family carers when their care recipient is hospitalised and after discharge. Methods: The study will recruit 180 family carers and older people. Family carers providing support for an older person without cognitive impairment who has been admitted to a private metropolitan hospital in Western Australia and assessed to have a risk of falling will be included. Data will be collected using an interviewer-administered survey. All participants will complete the survey within 48 h before the patient\u27s discharge, follow-up one week later (only for family carers), and again 30 days after the patient is discharged. Data related to falls, fall concern, psychological distress, and quality of life will be obtained from family carers and care recipients. Discussion: This study will provide deeper understanding about the factors affecting fall concern among family carers of older people during hospitalisation and after discharge. This will help healthcare professionals better support family carers to implement fall prevention strategies for older people whilst in hospital and in the community

Reanalysis and Simulation Suggest a Phylogenetic Microarray Does Not Accurately Profile Microbial Communities

The second generation (G2) PhyloChip is designed to detect over 8700 bacteria and archaeal and has been used over 50 publications and conference presentations. Many of those publications reveal that the PhyloChip measures of species richness greatly exceed statistical estimates of richness based on other methods. An examination of probes downloaded from Greengenes suggested that the system may have the potential to distort the observed community structure. This may be due to the sharing of probes by taxa; more than 21% of the taxa in that downloaded data have no unique probes. In-silico simulations using these data showed that a population of 64 taxa representing a typical anaerobic subterranean community returned 96 different taxa, including 15 families incorrectly called present and 19 families incorrectly called absent. A study of nasal and oropharyngeal microbial communities by Lemon et al (2010) found some 1325 taxa using the G2 PhyloChip, however, about 950 of these taxa have, in the downloaded data, no unique probes and cannot be definitively called present. Finally, data from Brodie et al (2007), when re-examined, indicate that the abundance of the majority of detected taxa, are highly correlated with one another, suggesting that many probe sets do not act independently. Based on our analyses of downloaded data, we conclude that outputs from the G2 PhyloChip should be treated with some caution, and that the presence of taxa represented solely by non-unique probes be independently verified

Gene expression in Citrus sinensis fruit tissues harvested from huanglongbing-infected trees: comparison with girdled fruit

Distribution of viable Candidatus Liberibacter asiaticus (CaLas) in sweet orange fruit and leaves (‘Hamlin’ and ‘Valencia’) and transcriptomic changes associated with huanglongbing (HLB) infection in fruit tissues are reported. Viable CaLas was present in most fruit tissues tested in HLB trees, with the highest titre detected in vascular tissue near the calyx abscission zone. Transcriptomic changes associated with HLB infection were analysed in flavedo (FF), vascular tissue (VT), and juice vesicles (JV) from symptomatic (SY), asymptomatic (AS), and healthy (H) fruit. In SY ‘Hamlin’, HLB altered the expression of more genes in FF and VT than in JV, whereas in SY ‘Valencia’, the number of genes whose expression was changed by HLB was similar in these tissues. The expression of more genes was altered in SY ‘Valencia’ JV than in SY ‘Hamlin’ JV. More genes were also affected in AS ‘Valencia’ FF and VT than in AS ‘Valencia’ JV. Most genes whose expression was changed by HLB were classified as transporters or involved in carbohydrate metabolism. Physiological characteristics of HLB-infected and girdled fruit were compared to differentiate between HLB-specific and carbohydrate metabolism-related symptoms. SY and girdled fruit were smaller than H and ungirdled fruit, respectively, with poor juice quality. However, girdling did not cause misshapen fruit or differential peel coloration. Quantitative PCR analysis indicated that many selected genes changed their expression significantly in SY flavedo but not in girdled flavedo. Mechanisms regulating development of HLB symptoms may lie in the host disease response rather than being a direct consequence of carbohydrate starvation

Novel paradigms for the gut–brain axis during alcohol withdrawal, withdrawal-associated depression, and craving in patients with alcohol use disorder

IntroductionPatients with alcohol use disorder (AUD) exhibit symptoms such as alcohol withdrawal, depression, and cravings. The gut-immune response may play a significant role in manifesting these specific symptoms associated with AUD. This study examined the role of gut dysfunction, proinflammatory cytokines, and hormones in characterizing AUD symptoms.MethodsForty-eight AUD patients [men (n = 34) and women (n = 14)] aged 23–63 years were grouped using the Clinical Institute Withdrawal Assessment of Alcohol Scale (CIWA) as clinically significant (CS-CIWA [score > 10] [n = 22]) and a clinically not-significant group (NCS-CIWA [score ≤ 10] [n = 26]). Clinical data (CIWA, 90-day timeline followback [TLFB90], and lifetime drinking history [LTDH]) and blood samples (for testing proinflammatory cytokines, hormones, and markers of intestinal permeability) were analyzed. A subset of 16 AUD patients was assessed upon admission for their craving tendencies related to drug-seeking behavior using the Penn-Alcohol Craving Score (PACS).ResultsCS-CIWA group patients exhibited unique and significantly higher levels of adiponectin and interleukin (IL)-6 compared to NCS-CIWA. In the CS group, there were significant and high effects of association for the withdrawal score with gut-immune markers (lipopolysaccharide [LPS], adiponectin, IL-6, and IL-8) and for withdrawal-associated depression with gut-immune markers (scored using MADRS with LPS, soluble cells of differentiation type 14 [sCD14], IL-6, and IL-8). Craving (assessed by PACS, the Penn-Alcohol Craving Scale) was significantly characterized by what could be described as gut dysregulation (LBP [lipopolysaccharide binding protein] and leptin) and candidate proinflammatory (IL-1β and TNF-α) markers. Such a pathway model describes the heavy drinking phenotype, HDD90 (heavy drinking days past 90 days), with even higher effects (R2 = 0.955, p = 0.006) in the AUD patients, who had higher ratings for cravings (PACS > 5).DiscussionThe interaction of gut dysfunction cytokines involved in both inflammation and mediating activity constitutes a novel pathophysiological gut–brain axis for withdrawal symptoms and withdrawal-associated depression and craving symptoms in AUD. AUD patients with reported cravings show a significant characterization of the gut–brain axis response to heavy drinking.Trial registrationClinicalTrials.gov, identifier: NCT# 00106106

Functional analyses of heterotrimeric G protein Gα and Gβ subunits in Gibberella zeae

The homothallic ascomycete fungus Gibberella zeae (anamorph: Fusarium graminearum) is a major toxigenic plant pathogen that causes head blight disease on small-grain cereals. The fungus produces the mycotoxins deoxynivalenol (DON) and zearalenone (ZEA) in infected hosts, posing a threat to human and animal health. Despite its agricultural and toxicological importance, the molecular mechanisms underlying its growth, development and virulence remain largely unknown. To better understand such mechanisms, we studied the heterotrimeric G proteins of G. zeae, which are known to control crucial signalling pathways that regulate various cellular and developmental responses in fungi. Three putative Gα subunits, GzGPA1, GzGPA2 and GzGPA3, and one Gβ subunit, GzGPB1, were identified in the F. graminearum genome. Deletion of GzGPA1, a homologue of the Aspergillus nidulans Gα gene fadA, resulted in female sterility and enhanced DON and ZEA production, suggesting that GzGPA1 is required for normal sexual reproduction and repression of toxin biosynthesis. The production of DON and ZEA was also enhanced in the GzGPB1 mutant, suggesting that both Gα GzGPA1 and Gβ GzGPB1 negatively control mycotoxin production. Deletion of GzGPA2, which encodes a Gα protein similar to A. nidulans GanB, caused reduced pathogenicity and increased chitin accumulation in the cell wall, implying that GzGPA2 has multiple functions. Our study shows that G. zeae heterotrimeric G protein subunits can regulate vegetative growth, sexual development, toxin production and pathogenicity

Structure-Activity Determinants in Antifungal Plant Defensins MsDef1 and MtDef4 with Different Modes of Action against Fusarium graminearum

Plant defensins are small cysteine-rich antimicrobial proteins. Their three-dimensional structures are similar in that they consist of an α-helix and three anti-parallel β-strands stabilized by four disulfide bonds. Plant defensins MsDef1 and MtDef4 are potent inhibitors of the growth of several filamentous fungi including Fusarium graminearum. However, they differ markedly in their antifungal properties as well as modes of antifungal action. MsDef1 induces prolific hyperbranching of fungal hyphae, whereas MtDef4 does not. Both defensins contain a highly conserved γ-core motif (GXCX3–9C), a hallmark signature present in the disulfide-stabilized antimicrobial peptides, composed of β2 and β3 strands and the interposed loop. The γ-core motifs of these two defensins differ significantly in their primary amino acid sequences and in their net charge. In this study, we have found that the major determinants of the antifungal activity and morphogenicity of these defensins reside in their γ-core motifs. The MsDef1-γ4 variant in which the γ-core motif of MsDef1 was replaced by that of MtDef4 was almost as potent as MtDef4 and also failed to induce hyperbranching of fungal hyphae. Importantly, the γ-core motif of MtDef4 alone was capable of inhibiting fungal growth, but that of MsDef1 was not. The analysis of synthetic γ-core variants of MtDef4 indicated that the cationic and hydrophobic amino acids were important for antifungal activity. Both MsDef1 and MtDef4 induced plasma membrane permeabilization; however, kinetic studies revealed that MtDef4 was more efficient in permeabilizing fungal plasma membrane than MsDef1. Furthermore, the in vitro antifungal activity of MsDef1, MsDef1-γ4, MtDef4 and peptides derived from the γ-core motif of each defensin was not solely dependent on their ability to permeabilize the fungal plasma membrane. The data reported here indicate that the γ-core motif defines the unique antifungal properties of each defensin and may facilitate de novo design of more potent antifungal peptides