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1.
J Oral Maxillofac Surg ; 82(7): 782-791, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38643964

ABSTRACT

BACKGROUND: The existing data on the link between body mass index (BMI), operative characteristics, and surgical outcomes across orthognathic surgery are limited. PURPOSE: The purpose was to measure the association between BMI and early postoperative outcomes in orthognathic surgery. STUDY DESIGN, SETTING, AND SAMPLE: This is a retrospective cohort study of patients (n = 118) aged > 14 years undergoing bimaxillary orthognathic surgery between 2015 and 2018 by a single surgeon within the Kaiser Permanente Northern California-integrated healthcare system. Patients undergoing unilateral or additional procedures, history of prior orthognathic surgery, or pre-existing pain conditions were excluded. PREDICTOR VARIABLE: The predictor variable was BMI measured as a continuous (kg/m2) and categorical variable (underweight/normal, overweight, obese). MAIN OUTCOME VARIABLE(S): The primary outcome variables were additional postoperative antibiotics, increased postoperative visits, wound dehiscence, and wound infection. The secondary outcome variables were total operative and anesthesia time. COVARIATES: The demographic covariates included age, sex, and race/ethnicity. The clinical covariates included history of obstructive sleep apnea, Mallampati score, tobacco use, American Society of Anesthesia classification, thyromental distance, history of difficult intubation, and Angle's classification. ANALYSES: Bivariate and multivariate analyses were performed to measure the associations between BMI and the primary and secondary outcomes. Multivariable logistic regression analyses were used to measure associations between BMI and the postoperative outcomes. Statistical significance was defined as P < .05. RESULTS: The study sample was composed of 118 subjects with a mean age of 26.91 years (standard deviation 9.43). Forty-seven percent (n = 55) were male, and the mean BMI was 25.13 (standard deviation 5.19). BMI category was significantly associated with age, with increasing age associated with higher BMI category (P = .02). According to the bivariate and multivariable logistic regression analyses, controlling for age, race/ethnicity, BMI, and total operative time, increased total operative time was associated with additional postoperative antibiotics (odds ratio = 1.03, 95% confidence interval: 1.01, 1.05), and increased postoperative appointments (odds ratio = 1.02, 95% confidence interval: 1.01, 1.04). No significant association between BMI and other clinical or operative characteristics was seen aside from American Society of Anesthesia classification. CONCLUSION AND RELEVANCE: Elevated BMI was not associated with worsened operative characteristics or postoperative outcomes. This supports the suitability of orthognathic surgery in a BMI-diverse population.


Subject(s)
Body Mass Index , Orthognathic Surgical Procedures , Postoperative Complications , Humans , Male , Female , Retrospective Studies , Adult , Treatment Outcome , Adolescent , Young Adult , Middle Aged , Operative Time
2.
J Head Trauma Rehabil ; 37(2): E65-E70, 2022.
Article in English | MEDLINE | ID: mdl-33782348

ABSTRACT

OBJECTIVE: To establish whether poor parental supervision is associated with head injury and self-reported reactive aggression (ie, aggression in response to perceived provocation or threat) in adolescents in a Young Offender's Institute, by examining correlations between these variables. Understanding this population is important, as they are at a key pivotal age for intervention to prevent lifelong reoffending. METHODS: Ninety-six male participants aged 16 to 18 years were recruited from a UK Young Offender's Institute. Self-report measures of remembered parenting, reactive aggression, and head injury history were administered during individual interviews. RESULTS: Seventy-four percent of participants reported having experienced a lifetime traumatic brain injury (TBI), and 46% of participants reported experiencing at least 1 TBI leading to a loss of consciousness (LOC). We found that poor parental supervision, length of LOC following TBI, and self-reported reactive aggression were all positively correlated. CONCLUSIONS: Findings show that there are correlational relationships between poor parental supervision, length of LOC following lifetime TBI, and higher levels of self-reported reactive aggression. This suggests there may be pathways resulting from poor parental supervision leading to both TBI with LOC, and reactive aggression. We advocate for future research with longitudinal designs and larger samples to examine the nature of these interactions, and to establish whether poor parental supervision is a prospective risk factor for more TBIs leading to LOC, and reactive aggression. This is key to understanding whether parenting interventions could help to reduce the disabling effects of TBI in adolescents, and help to prevent contact with the law.


Subject(s)
Brain Injuries, Traumatic , Criminals , Adolescent , Aggression , Brain Injuries, Traumatic/complications , Humans , Male , Parents , Prospective Studies , Unconsciousness/epidemiology
3.
BMC Plant Biol ; 21(1): 138, 2021 Mar 16.
Article in English | MEDLINE | ID: mdl-33726668

ABSTRACT

BACKGROUND: Maize (Zea mays L.) is a major cereal crop, with the United States accounting for over 40% of the worldwide production. Corn leaf aphid [CLA; Rhopalosiphum maidis (Fitch)] is an economically important pest of maize and several other monocot crops. In addition to feeding damage, CLA acts as a vector for viruses that cause devastating diseases in maize. We have shown previously that the maize inbred line Mp708, which was developed by classical plant breeding, provides heightened resistance to CLA. However, the transcriptomic variation conferring CLA resistance to Mp708 has not been investigated. RESULTS: In this study, we contrasted the defense responses of the resistant Mp708 genotype to those of the susceptible Tx601 genotype at the transcriptomic (mRNA-seq) and volatile blend levels. Our results suggest that there was a greater transcriptomic remodeling in Mp708 plants in response to CLA infestation compared to the Tx601 plants. These transcriptomic signatures indicated an activation of hormonal pathways, and regulation of sesquiterpenes and terpenoid synthases in a constitutive and inducible manner. Transcriptomic analysis also revealed that the resistant Mp708 genotype possessed distinct regulation of ethylene and jasmonic acid pathways before and after aphid infestation. Finally, our results also highlight the significance of constitutive production of volatile organic compounds (VOCs) in Mp708 and Tx601 plants that may contribute to maize direct and/or indirect defense responses. CONCLUSIONS: This study provided further insights to understand the role of defense signaling networks in Mp708's resistance to CLA.


Subject(s)
Aphids , Crops, Agricultural/genetics , Crops, Agricultural/parasitology , Gene Expression Profiling , Herbivory , Zea mays/genetics , Zea mays/parasitology , Animals , Gene Expression Regulation, Plant , Genes, Plant , Genetic Variation , United States
4.
BMC Fam Pract ; 22(1): 32, 2021 02 05.
Article in English | MEDLINE | ID: mdl-33546608

ABSTRACT

BACKGROUND: Rural settings in low- and middle-income countries are bedeviled with poverty and high disease burden, and lack adequate resources to deliver quality healthcare to the population. Drug shortage and inadequate number and skill-mix of healthcare providers is very common in rural health facilities. Hence, rural healthcare providers have no choice but to be innovative and introduce some strategies to cope with health delivery challenges at the health centre levels. This study explored how and why rural healthcare providers cope with clinical care delivery challenges at the health centre levels in Ghana. METHODS: This study was a multiple case studies involving three districts: Bongo, Kintampo North, and Juaboso districts. In each case study district, a cross-sectional design was used to explore the research question. Purposive sampling technique was used to select study sites and the study participants. The authors conducted 11 interviews, 9 focus group discussions (involving 61 participants), and 9-week participant observation (in 3 health centres). Transcription of the voice-recordings was done verbatim, cleaned and imported into the Nvivo version 11 platform for analysis. Data was analysed using the inductive content analysis approach. Ethical clearance was granted by the Ethics Review Committee of the Ghana Health Service. RESULTS: The study found three main coping strategies (borrowing, knowledge sharing and multi-tasking). First, borrowing arrangements among primary health care institutions help to address the periodic shortage of medical supplies at the health centres. Secondly, knowledge sharing among healthcare providers mitigates skills gap during service delivery; and finally, rural healthcare providers use multi-tasking to avert staff inadequacy challenges during service delivery at the health centre levels. CONCLUSION: Borrowing, knowledge sharing, and multi-tasking are coping strategies that are sustaining and potentially improving health outcomes at the district levels in Ghana. We recommend that health facilities across all levels of care in Ghana and other settings with similar challenges could adopt and modify these strategies in order to ensure quality healthcare delivery amidst delivery challenges.


Subject(s)
Health Personnel , Rural Population , Adaptation, Psychological , Cross-Sectional Studies , Ghana , Humans , Patient Acceptance of Health Care , Qualitative Research
5.
J Occup Environ Hyg ; 18(4-5): 203-211, 2021.
Article in English | MEDLINE | ID: mdl-33819135

ABSTRACT

Firefighters' protective clothing (FPC) can limit human thermoregulation due to limited water vapor permeability and insulation. This study investigated the effect of cooling on the physiological responses and probability of hyperthermia in subjects wearing FPC during exercise in a hot environment. Twelve males participated in this study. A maximal graded treadmill exercise test was performed to measure maximal oxygen uptake (V̇O2max) and to assess subjects' capacity to perform the assigned exercise. Exercise included treadmill walking at 40% V̇O2max in warm (30 °C) and humid (70% RH) conditions for 40 min while wearing FPC. Subjects participated in two randomly counterbalanced assigned experimental protocols: control (no cooling) and intervention (cooling). The experimental intervention consisted of a cooling garment infused with cooled water (18 °C) through silastic tubing sewn into the fabric and worn underneath FPC. Each subject served as their own control and, therefore, completed both the control and intervention of the protocol. A logistic regression model was used to analyze the interaction effect of cooling on the probability of progression to hyperthermia (Tc ≥ 38 °C). Subjects' physiological responses increased during exercise in a warm and humid environment. Active cooling decreased (p < 0.05) the thermal stress thereby reducing the probability of hyperthermia while exercising in hot and humid conditions. The results indicate that when cooling was used each subject, on average, was 91% less likely to reach the lower threshold limit of hyperthermia. Exercise in hot environments while wearing FPC results in significant physiological strain, which may lead to hyperthermia. Utilization of a cooling garment reduced physiological strain and the probability of hyperthermia.


Subject(s)
Firefighters , Body Temperature , Body Temperature Regulation , Heart Rate , Hot Temperature , Humans , Hyperthermia , Male , Probability , Protective Clothing
6.
Plant Physiol ; 179(4): 1402-1415, 2019 04.
Article in English | MEDLINE | ID: mdl-30643012

ABSTRACT

The corn leaf aphid (CLA; Rhopalosiphum maidis) is a phloem sap-sucking insect that attacks many cereal crops, including maize (Zea mays). We previously showed that the maize inbred line Mp708, which was developed by classical plant breeding, provides enhanced resistance to CLA. Here, using electrophysiological monitoring of aphid feeding behavior, we demonstrate that Mp708 provides phloem-mediated resistance to CLA. Furthermore, feeding by CLA on Mp708 plants enhanced callose deposition, a potential defense mechanism utilized by plants to limit aphid feeding and subsequent colonization. In maize, benzoxazinoids (BX) or BX-derived metabolites contribute to enhanced callose deposition by providing heightened resistance to CLA. However, BX and BX-derived metabolites were not significantly altered in CLA-infested Mp708 plants, indicating BX-independent defense against CLA. Evidence presented here suggests that the constitutively higher levels of 12-oxo-phytodienoic acid (OPDA) in Mp708 plants contributed to enhanced callose accumulation and heightened CLA resistance. OPDA enhanced the expression of ethylene biosynthesis and receptor genes, and the synergistic interactions of OPDA and CLA feeding significantly induced the expression of the transcripts encoding Maize insect resistance1-Cysteine Protease, a key defensive protein against insect pests, in Mp708 plants. Furthermore, exogenous application of OPDA on maize jasmonic acid-deficient plants caused enhanced callose accumulation and heightened resistance to CLA, suggesting that the OPDA-mediated resistance to CLA is independent of the jasmonic acid pathway. We further demonstrate that the signaling function of OPDA, rather than a direct toxic effect, contributes to enhanced CLA resistance in Mp708.


Subject(s)
Aphids/physiology , Fatty Acids, Unsaturated/physiology , Glucans/metabolism , Zea mays/physiology , Acetates , Animals , Benzoxazines/metabolism , Cyclopentanes , Ethylenes/biosynthesis , Fertility , Herbivory , Oxylipins , Phloem/physiology
7.
Food Control ; 118: 107363, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33273755

ABSTRACT

The widespread contamination of foods by mycotoxins continues to be a public health hazard in sub-Saharan Africa, with maize and groundnut being major sources of contamination. This study was undertaken to assess the hypothesis that grain sorting can be used to reduce mycotoxin contamination in grain lots by removing toxic kernels. We tested a set of sorting principles and methods for reducing mycotoxin levels in maize and groundnut from a variety of genotypes and environments. We found that kernel bulk density (KBD) and 100-kernel weight (HKW) were associated with the levels of aflatoxins (AF) and fumonisins (FUM) in maize grain. A low-cost sorter prototype (the 'DropSort' device) that separated maize grain based on KBD and HKW was more effective in reducing FUM than AF. We then evaluated the effectiveness of DropSorting when combined with either size or visual sorting. Size sorting followed by DropSorting was the fastest method for reducing FUM to under 2 ppm, but was not effective in reducing AF levels in maize grain to under 20 ppb, especially for heavily AF-contaminated grain. Analysis of individual kernels showed that high -AF maize kernels had lower weight, volume, density, length, and width and higher sphericity than those with low AF. Single kernel weight was the most significant predictor of AF concentration. The DropSort excluded kernels with lower single kernel weight, volume, width, depth, and sphericity. We also found that visual sorting and bright greenish-yellow fluorescence sorting of maize single kernels were successful in separating kernels based on AF levels. For groundnut, the DropSort grouped grain based on HKW and did not significantly reduce AF concentrations, whereas size sorting and visual sorting were much more effective.

8.
J Occup Environ Hyg ; 17(5): 243-252, 2020 05.
Article in English | MEDLINE | ID: mdl-32150701

ABSTRACT

Firefighting is physically and mentally strenuous, requiring rapid, appropriate decision-making in hot environments. Intact cognitive function is imperative to firefighters' effectiveness and safety. The study purpose was to investigate the effect of hyperthermia and the effect of body cooling on sustained attention and response inhibition while wearing firefighters' personal protective ensembles after exercise in a hot environment. Twelve healthy males were recruited to participate in two randomly assigned exercise sessions (walking on a treadmill for 40 min at 40% [Formula: see text] O2max while wearing firefighter's protective ensemble) in a hot environment: control (no cooling) and intervention (cooling). For intervention sessions, a cooling garment was worn underneath firefighter's protective ensemble and infused with 18 °C water supplied by an external water circulator. Participants performed a computerized Go/No-Go (a measure of cognitive function) test three times at baseline and post-exercise for each experimental session. Participants completed baseline testing while wearing cotton athletic clothing. The exercise continued until the core temperature reached ∼39 °C (for all subjects regardless of cooling or non-cooling experimental sessions). Following hyperthermia, participants' physiological responses were significantly increased after exercise. Subjects' reaction time was significantly reduced (improved) after experiencing thermal strain and reaching hyperthermia. The cooling method had a significant impact on suppressing the physiological load, i.e., body cooling delayed the time to reach a Tc of 39 °C (p ≤ 0.05), but not cognitive inhibition and attention (reaction time and accuracy). Unexpectedly, hyperthermia resulted in shorter reaction time following exercise (16.64 ± 5.62; p < 0.03), likely influenced by increased attention/vigilance. Hyperthermia may trigger an acute increase in alertness, causing decreased reaction time.


Subject(s)
Body Temperature Regulation , Body Temperature/physiology , Cognition/physiology , Cold Temperature , Heart Rate/physiology , Hot Temperature/adverse effects , Protective Clothing/standards , Adult , Cross-Sectional Studies , Firefighters , Humans , Male , Young Adult
9.
Theor Appl Genet ; 132(10): 2899-2912, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31321473

ABSTRACT

KEY MESSAGE: The widely divergent species 4xTrifolium ambiguum and 2xT.occidentale are inter-fertile long after speciation (including polyploidisation) has occurred. Tri-species hybrids (T. repens × T. ambiguum × T. occidentale) have the potential to achieve introgression of stress resistant traits from both wild species into white clover. Trifolium ambiguum and T. occidentale are geographically, adaptionally and phenotypically contrasting species in the white clover section (Trifoliastrum) of the genus. T. ambiguum occurs as a high-altitude polyploid series (2x, 4x, 6x) in W Asia and NE Europe. T. occidentale is a diploid coastal species, occurring at sea level in W Europe. This study investigated hybridisation between 4xT. ambiguum and 2xT. occidentale and considered the significance of the hybrids for introgression breeding of white clover. Partially fertile F1 hybrids between 4xT. ambiguum and 2x and 4xT. occidentale were generated by embryo rescue. Hybrid plant morphology and fertility varied widely and hybrids generally expressed traits from both species. Advanced generation (F2-F5) 4x hybrids were highly fertile and constitute a new synthetic allotetraploid species. FISH analyses of 4x hybrids showed multivalent chromosome configurations with homoeologous associations between T. ambiguum and T. occidentale chromosomes. Crosses of the hybrids with T. repens produced fertile tri-species progeny. These very divergent species remain inter-fertile long after speciation (including polyploidisation) has occurred. Tri-species hybrids have the potential to achieve introgression of stress resistance traits from both wild species into white clover.


Subject(s)
Genome, Plant , Hybridization, Genetic , Plant Breeding/methods , Polyploidy , Trifolium/genetics , Genotype , Geography , Phenotype , Trifolium/growth & development
10.
Int J Biometeorol ; 63(3): 405-427, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30710251

ABSTRACT

Exertional heat illness (EHI) risk is a serious concern among athletes, laborers, and warfighters. US Governing organizations have established various activity modification guidelines (AMGs) and other risk mitigation plans to help ensure the health and safety of their workers. The extent of metabolic heat production and heat gain that ensue from their work are the core reasons for EHI in the aforementioned population. Therefore, the major focus of AMGs in all settings is to modulate the work intensity and duration with additional modification in adjustable extrinsic risk factors (e.g., clothing, equipment) and intrinsic risk factors (e.g., heat acclimatization, fitness, hydration status). Future studies should continue to integrate more physiological (e.g., valid body fluid balance, internal body temperature) and biometeorological factors (e.g., cumulative heat stress) to the existing heat risk assessment models to reduce the assumptions and limitations in them. Future interagency collaboration to advance heat mitigation plans among physically active population is desired to maximize the existing resources and data to facilitate advancement in AMGs for environmental heat.


Subject(s)
Exercise , Heat Stress Disorders/prevention & control , Hot Temperature , Acclimatization , Athletes , Guidelines as Topic , Humans , Military Personnel , Occupational Health , United States
11.
Planta ; 247(4): 863-873, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29260396

ABSTRACT

MAIN CONCLUSION: Chemical isolation and NMR-based structure elucidation revealed a novel keto-acidic sesquiterpenoid, termed zealexin A4 (ZA4). ZA4 is elicited by pathogens and herbivory, but attenuated by heightened levels of CO 2 . The identification of the labdane-related diterpenoids, termed kauralexins and acidic sesquiterpenoids, termed zealexins, demonstrated the existence of at least ten novel stress-inducible maize metabolites with diverse antimicrobial activity. Despite these advances, the identity of co-occurring and predictably related analytes remains largely unexplored. In the current effort, we identify and characterize the first sesquiterpene keto acid derivative of ß-macrocarpene, named zealexin A4 (ZA4). Evaluation of diverse maize inbreds revealed that ZA4 is commonly produced in maize scutella during the first 14 days of seedling development; however, ZA4 production in the scutella was markedly reduced in seedlings grown in sterile soil. Elevated ZA4 production was observed in response to inoculation with adventitious fungal pathogens, such as Aspergillus flavus and Rhizopus microsporus, and a positive relationship between ZA4 production and expression of the predicted zealexin biosynthetic genes, terpene synthases 6 and 11 (Tps6 and Tps11), was observed. ZA4 exhibited significant antimicrobial activity against the mycotoxigenic pathogen A. flavus; however, ZA4 activity against R. microsporus was minimal, suggesting the potential of some fungi to detoxify ZA4. Significant induction of ZA4 production was also observed in response to infestation with the stem tunneling herbivore Ostrinia nubilalis. Examination of the interactive effects of elevated CO2 (E-CO2) on both fungal and herbivore-elicited ZA4 production revealed significantly reduced levels of inducible ZA4 accumulation, consistent with a negative role for E-CO2 on ZA4 production. Collectively, these results describe a novel ß-macrocarpene-derived antifungal defense in maize and expand the established diversity of zealexins that are differentially regulated in response to biotic/abiotic stress.


Subject(s)
Sesquiterpenes/metabolism , Zea mays/metabolism , Alkyl and Aryl Transferases/metabolism , Anti-Infective Agents/metabolism , Aspergillus flavus/metabolism , Carbon Dioxide/pharmacology , Gene Expression Regulation, Plant/drug effects , Plant Immunity , Rhizopus/metabolism , Seedlings/metabolism , Zea mays/drug effects , Zea mays/microbiology
12.
J Recept Signal Transduct Res ; 38(2): 101-111, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29402169

ABSTRACT

Purine nucleotides transduce cell membrane receptor responses and modulate ion channel activity. This is accomplished through conformational change in the structure of nucleotides and cell membrane associated proteins. The aim of this study is to enhance our understanding of nucleotide dependence in regard to signal transduction events, drug action and pharmacological promiscuity. Nucleotides and ligand structures regulating Gα protein subunits, voltage- and ligand-gated ion channels are investigated for molecular similarity using a computational program. Results differentiate agonist and antagonist structures, identify molecular similarity within nucleotide and ligand structures and demonstrate the potential of ligands to regulate nucleotide conformational change. Relative molecular similarity within nucleotides and the ligands of the major receptor classes provides insight into mechanisms of receptor and ion channel regulation. The nucleotide template model has some merit as an initial screening tool in the study and comparison of drug and hormone structures.


Subject(s)
Cells/metabolism , Hormones/metabolism , Neurotransmitter Agents/metabolism , Pharmaceutical Preparations/metabolism , Purine Nucleotides/chemistry , Signal Transduction , Adenosine Triphosphate/chemistry , Adenosine Triphosphate/metabolism , Animals , GTP-Binding Proteins/chemistry , GTP-Binding Proteins/metabolism , Ligands , Models, Molecular , Protein Subunits/chemistry , Protein Subunits/metabolism , Purine Nucleotides/metabolism
13.
Phys Rev Lett ; 121(5): 053001, 2018 Aug 03.
Article in English | MEDLINE | ID: mdl-30118286

ABSTRACT

We report spectroscopic results on the 2s2p^{1}P_{1} state in neutral atomic beryllium-9. The absolute frequency for the center of gravity is determined to be 42 565.4501(13) cm^{-1}, a factor of 130 more precise than the previous experimental measurement. The result is in agreement with and a factor of 8 more precise than the current best theoretical estimate of 42 565.441(11) cm^{-1}, which was calculated including the effects of quantum electrodynamics. Because of the large natural linewidth of the transition, the hyperfine constants were not able to be extracted to high precision.

14.
Ergonomics ; 61(11): 1560-1568, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30014772

ABSTRACT

This study aimed to determine if trunk posture during walking is related to increases in rectal temperature (Tre). 24 males treadmill walked in one of four conditions (1): 30 min at 3.0 mph and 0% grade, 20 °C and 50% relative humidity (RH), wearing healthcare worker (HCW) PPE; (2): 30 min at 3.0 mph and 0% grade, 27.5 °C and 60% RH, HCW PPE; (3): 30 min at 3.0 mph and 0% grade, 32.5 °C and 70% RH, HCW PPE; and (4): 40 min at 40% VO2max, 30 °C and 70% RH, wearing firefighter PPE. Trunk posture (Zephyr BioHarness 3) and Tre were measured continuously. Tre was positively related to trunk posture, controlling for covariates (B = 3.49, p < .001). BMI and age moderated this relationship (Tre×age, B = 0.76, p < .001; Tre*BMI, B = -1.85, p < .001). Trunk posture measurement may be useful in monitoring fall potential and magnitude of heat stress of workers in hot environments. Practitioner Summary: Occupational hyperthermia increases worker risk for heat illness and injury but is difficult to monitor in the field. This investigation shows that trunk posture is independently and positively related to core temperature. Non-invasive measurement or visual inspection of trunk posture could provide novel insight on individual heat strain level.


Subject(s)
Heat Stress Disorders/physiopathology , Hot Temperature/adverse effects , Occupational Diseases/physiopathology , Posture/physiology , Walking/physiology , Adult , Body Mass Index , Fever/etiology , Heat Stress Disorders/etiology , Humans , Male , Occupational Diseases/etiology , Pilot Projects , Protective Clothing/adverse effects , Work
15.
J Chem Ecol ; 43(11-12): 1109-1123, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29151152

ABSTRACT

Insect resistance against root herbivores like the western corn rootworm (WCR, Diabrotica virgifera virgifera) is not well understood in non-transgenic maize. We studied the responses of two American maize inbreds, Mp708 and Tx601, to WCR infestation using biomechanical, molecular, biochemical analyses, and laser ablation tomography. Previous studies performed on several inbreds indicated that these two maize genotypes differed in resistance to pests including fall armyworm (Spodoptera frugiperda) and WCR. Our data confirmed that Mp708 shows resistance against WCR, and demonstrates that the resistance mechanism is based in a multi-trait phenotype that includes increased resistance to cutting in nodal roots, stable root growth during insect infestation, constitutive and induced expression of known herbivore-defense genes, including ribosomal inhibitor protein 2 (rip2), terpene synthase 23 (tps23) and maize insect resistance cysteine protease-1 (mir1), as well high constitutive levels of jasmonic acid and production of (E)-ß-caryophyllene. In contrast, Tx601 is susceptible to WCR. These findings will facilitate the use of Mp708 as a model to explore the wide variety of mechanisms and traits involved in plant defense responses and resistance to herbivory by insects with several different feeding habits.


Subject(s)
Coleoptera/physiology , Zea mays/metabolism , Alkyl and Aryl Transferases/genetics , Alkyl and Aryl Transferases/metabolism , Animals , Cyclopentanes/analysis , Cyclopentanes/metabolism , Gene Expression Regulation, Plant , Herbivory , Oxylipins/analysis , Oxylipins/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Roots/growth & development , Plant Roots/metabolism , Plant Roots/parasitology , Polycyclic Sesquiterpenes , RNA, Plant/isolation & purification , RNA, Plant/metabolism , Sesquiterpenes/analysis , Sesquiterpenes/metabolism , Zea mays/chemistry , Zea mays/parasitology
16.
Plant Physiol ; 169(1): 313-24, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26253737

ABSTRACT

Signaling networks among multiple phytohormones fine-tune plant defense responses to insect herbivore attack. Previously, it was reported that the synergistic combination of ethylene (ET) and jasmonic acid (JA) was required for accumulation of the maize insect resistance1 (mir1) gene product, a cysteine (Cys) proteinase that is a key defensive protein against chewing insect pests in maize (Zea mays). However, this study suggests that mir1-mediated resistance to corn leaf aphid (CLA; Rhopalosiphum maidis), a phloem sap-sucking insect pest, is independent of JA but regulated by the ET-signaling pathway. Feeding by CLA triggers the rapid accumulation of mir1 transcripts in the resistant maize genotype, Mp708. Furthermore, Mp708 provided elevated levels of antibiosis (limits aphid population)- and antixenosis (deters aphid settling)-mediated resistance to CLA compared with B73 and Tx601 maize susceptible inbred lines. Synthetic diet aphid feeding trial bioassays with recombinant Mir1-Cys Protease demonstrates that Mir1-Cys Protease provides direct toxicity to CLA. Furthermore, foliar feeding by CLA rapidly sends defensive signal(s) to the roots that trigger belowground accumulation of the mir1, signifying a potential role of long-distance signaling in maize defense against the phloem-feeding insects. Collectively, our data indicate that ET-regulated mir1 transcript accumulation, uncoupled from JA, contributed to heightened resistance to CLA in maize. In addition, our results underscore the significance of ET acting as a central node in regulating mir1 expression to different feeding guilds of insect herbivores.


Subject(s)
Aphids/physiology , Ethylenes/pharmacology , Phloem/parasitology , Plant Leaves/parasitology , Plant Proteins/metabolism , Zea mays/immunology , Zea mays/parasitology , Animals , Aphids/drug effects , Cyclopentanes/pharmacology , Gene Expression Regulation, Plant/drug effects , Herbivory/drug effects , Inbreeding , Models, Biological , Oxylipins/pharmacology , Phloem/drug effects , Plant Exudates/metabolism , Plant Leaves/drug effects , Plant Proteins/genetics , Salicylic Acid/pharmacology , Signal Transduction/drug effects , Zea mays/drug effects , Zea mays/genetics
17.
Psychol Med ; 46(7): 1485-96, 2016 May.
Article in English | MEDLINE | ID: mdl-26875722

ABSTRACT

BACKGROUND: To determine the functional integrity of the neural systems involved in emotional responding/regulation and response control/inhibition in youth (age 10-18 years) with disruptive behavioral disorders (DBDs: conduct disorder and/or oppositional defiant disorder) as a function of callous-unemotional (CU) traits. METHOD: Twenty-eight healthy youths and 35 youths with DBD [high CU (HCU), n = 18; low CU (LCU), n = 17] performed the fMRI Affective Stroop task. Participants viewed positive, neutral, and negative images under varying levels of cognitive load. A 3-way ANOVA (group×emotion by task) was conducted on the BOLD response data. RESULTS: Youth with DBD-HCU showed significantly less activation of ventromedial prefrontal cortex (vmPFC) and amygdala in response to negative stimuli, compared to healthy youth and youth with DBD-LCU. vmPFC responsiveness was inversely related to CU symptoms in DBD. Youth with DBD-LCU showed decreased functional connectivity between amygdala and regions including inferior frontal gyrus in response to emotional stimuli. Youth with DBD (LCU and HCU) additionally showed decreased insula responsiveness to high load (incongruent trials) compared to healthy youth. Insula responsiveness was inversely related to ADHD symptoms in DBD. CONCLUSIONS: These data reveal two forms of pathophysiology in DBD. One associated with reduced amygdala and vmPFC responses to negative stimuli and related to increased CU traits. Another associated with reduced insula responses during high load task trials and related to ADHD symptoms. Appropriate treatment will need to be individualized according to the patient's specific pathophysiology.


Subject(s)
Amygdala/physiopathology , Attention Deficit and Disruptive Behavior Disorders/physiopathology , Cerebral Cortex/physiopathology , Emotions/physiology , Inhibition, Psychological , Adolescent , Attention Deficit and Disruptive Behavior Disorders/classification , Child , Conduct Disorder/physiopathology , Female , Humans , Magnetic Resonance Imaging , Male , Prefrontal Cortex/physiopathology , Stroop Test
18.
Ann Bot ; 118(4): 699-710, 2016 Oct 01.
Article in English | MEDLINE | ID: mdl-27208735

ABSTRACT

Background and aims Traits related to root depth distribution were examined in Trifolium repens × T. uniflorum backcross 1 (BC1) hybrids to determine whether root characteristics of white clover could be improved by interspecific hybridization. Methods Two white clover cultivars, two T. uniflorum accessions and two BC1 populations were grown in 1 -m deep tubes of sand culture. Maximum rooting depth and root mass distribution were measured at four harvests over time, and root distribution data were fitted with a regression model to provide measures of root system shape. Morphological traits were measured at two depths at harvest 3. Key Results Root system shape of the hybrids was more similar to T. uniflorum than to white clover. The hybrids and T. uniflorum had a higher rate of decrease in root mass with depth than white clover, which would result in higher proportions of root mass in the upper profile. Percentage total root mass at 100-200 mm depth was higher for T. uniflorum than white clover, and for Crusader BC1 than 'Crusader'. Roots of the hybrids and T. uniflorum also penetrated deeper than those of white clover. T. uniflorum had thicker roots at 50-100 mm deep than the other entries, and more of its fine root mass at 400-500 mm. The hybrids and white clover had more of their fine root mass higher in the profile. Consequently, T. uniflorum had a higher root length density at 400-500 mm than most entries, and a smaller decrease in root length density with depth. Conclusions These results demonstrate that rooting characteristics of white clover can be altered by hybridization with T. uniflorum, potentially improving water and nutrient acquisition and drought resistance. Root traits of T. uniflorum are likely to be adaptations to soil moisture and fertility in its natural environment.

19.
Behav Anal ; 39(1): 167-73, 2016 May.
Article in English | MEDLINE | ID: mdl-27606197

ABSTRACT

The origins of the Behavior Analysis program at the University of Nevada, Reno by way of a self-capitalized model through its transition to a more typical graduate program is described. Details of the original proposal to establish the program and the funding model are described. Some of the unusual features of the program executed in this way are discussed, along with problems engendered by the model. Also included is the diversification of faculty interests over time. The status of the program, now, after 25 years of operation, is presented.

20.
BMC Genomics ; 16: 673, 2015 Sep 03.
Article in English | MEDLINE | ID: mdl-26334534

ABSTRACT

BACKGROUND: Aflatoxin is a potent carcinogen that can contaminate grain infected with the fungus Aspergillus flavus. However, resistance to aflatoxin accumulation in maize is a complex trait with low heritability. Here, two complementary analyses were performed to better understand the mechanisms involved. The first coupled results of a genome-wide association study (GWAS) that accounted for linkage disequilibrium among single nucleotide polymorphisms (SNPs) with gene-set enrichment for a pathway-based approach. The rationale was that the cumulative effects of genes in a pathway would give insight into genetic differences that distinguish resistant from susceptible lines of maize. The second involved finding non-pathway genes close to the most significant SNP-trait associations with the greatest effect on reducing aflatoxin in multiple environments. Unlike conventional GWAS, the latter analysis emphasized multiple aspects of SNP-trait associations rather than just significance and was performed because of the high genotype x environment variability exhibited by this trait. RESULTS: The most significant metabolic pathway identified was jasmonic acid (JA) biosynthesis. Specifically, there was at least one allelic variant for each step in the JA biosynthesis pathway that conferred an incremental decrease to the level of aflatoxin observed among the inbred lines in the GWAS panel. Several non-pathway genes were also consistently associated with lowered aflatoxin levels. Those with predicted functions related to defense were: leucine-rich repeat protein kinase, expansin B3, reversion-to-ethylene sensitivity1, adaptor protein complex2, and a multidrug and toxic compound extrusion protein. CONCLUSIONS: Our genetic analysis provided strong evidence for several genes that were associated with aflatoxin resistance. Inbred lines that exhibited lower levels of aflatoxin accumulation tended to share similar haplotypes for genes specifically in the pathway of JA biosynthesis, along with several non-pathway genes with putative defense-related functions. Knowledge gained from these two complementary analyses has improved our understanding of population differences in aflatoxin resistance.


Subject(s)
Aflatoxins/metabolism , Genome-Wide Association Study , Metabolic Networks and Pathways/genetics , Zea mays/genetics , Algorithms , Chromosomes, Plant/genetics , Decision Trees , Genes, Plant , Linkage Disequilibrium/genetics , Molecular Sequence Annotation , Polymorphism, Single Nucleotide/genetics , Quantitative Trait Loci/genetics , Reproducibility of Results
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