Envelope Stress Activates Expression of the Twin Arginine Translocation (Tat) System in Salmonella

The twin arginine translocation system (Tat) is a protein export system that is conserved in bacteria, archaea, and plants. In Gram-negative bacteria, it is required for the export of folded proteins from the cytoplasm to the periplasm. In Salmonella, there are 30 proteins that are predicted substrates of Tat, and among these are enzymes required for anaerobic respiration and peptidoglycan remodeling. We have demonstrated that some conditions that induce bacterial envelope stress activate expression of a ΔtatABC-lacZ fusion in Salmonella enterica serovar Typhimurium. Particularly, the addition of bile salts to the growth medium causes a 3-fold induction of a ΔtatABC-lacZ reporter fusion. Our data demonstrate that this induction is mediated via the phage shock protein (Psp) stress response system protein PspA. Further, we show that deletion of tatABC increases the induction of tatABC expression in bile salts. Indeed, the data suggest significant interaction between PspA and the Tat system in the regulatory response to bile salts. Although we have not identified the precise mechanism of Psp regulation of tatABC, our work shows that PspA is involved in the activation of tatABC expression by bile salts and adds another layer of complexity to the Salmonella response to envelope stress. IMPORTANCE Salmonella species cause an array of diseases in a variety of hosts. This research is significant in showing induction of the Tat system as a defense against periplasmic stress. Understanding the underlying mechanism of this regulation broadens our understanding of the Salmonella stress response, which is critical to the ability of the organism to cause infection.

Comparison of Color Attractiveness for Agrilus ruficollis (Coleoptera: Buprestidae): Potential for a Simple Trap

The rednecked cane borer, Agrilus ruficollis (F.), is a pest of cultivated and wild blackberries in the midwestern and eastern parts of the United States. Damage from this pest occurs from larvae girdling primocanes and tunneling in the pith, forming galls that can potentially reduce yields. There is only one registered insecticide and no trap available for monitoring. Paints mimicking the spectral reflectance of blackberry leaves and canes of both primocane and floricane were applied to wooden dowels or corrugated plastic mimicking the shape of blackberry canes and leaves. The dowels or corrugated plastic were covered with sticky Tangletrap, and field was evaluated for attractiveness to A. ruficollis for three years, with modifications to trap design each year. Commercially available emerald ash borer, Agrilus planipennis Fairmaire, funnel traps were evaluated for attractiveness to A. ruficollis in 2014. In 2011, the greatest numbers of A. ruficollis adults were captured on prism-shaped, primocane-mimicking traps that reflected light at a peak wavelength between 540-560 nm. In 2012 and 2013, field tests demonstrated that more A. ruficollis adults were captured on green emerald ash borer traps. Testing in 2014 reinforced the previous findings that A. ruficollis was most attracted to the green emerald ash borer traps. In 2013, it was noted that colored traps usually captured significantly more A. ruficollis males than females. This indicated a need to determine if there was a chemical cue used by A. ruficollis adult females to locate and oviposit on only blackberry primocanes and not floricanes.

Androgen signaling is a confounding factor for β-catenin-mediated prostate tumorigenesis

Emerging evidence has demonstrated the critical roles for both androgen and Wnt pathways in prostate tumorigenesis. A recent integrative genomic analysis of human prostate cancers has revealed a unique enrichment of androgen and Wnt signaling in early onset prostate cancers, implying their clinical significance in the disease. Additionally, interaction between the androgen receptor (AR) and β-catenin has long been detected in prostate cancer cells. However, the consequence of this interaction in prostate tumorigenesis is still unknown. Because mutations in adenomatous polyposis coli (APC), β-catenin, and other components of the destruction-complex are generally rare in prostate cancers, other mechanisms of aberrant Wnt signaling activation have been speculated. To address these critical questions, we developed Ctnnb1^L(ex3)/+/R26hAR^L/+:PB-Cre4 mice, in which transgenic AR and stabilized β-catenin are co-expressed in prostatic epithelial cells. We observed accelerated tumor development, aggressive tumor invasion, and a decreased survival rate in Ctnnb1^L(ex3)/+/R26hAR^L/+:PB-Cre4 compound mice compared to age-matched Ctnnb1^L(ex3)/+:PB-Cre4 littermate controls, which only have stabilized β-catenin expression in the prostate. Castration of the above transgenic mice resulted in significant tumor regression, implying an essential role of androgen signaling in tumor growth and maintenance. Implantation of the prostatic epithelial cells isolated from the transgenic mice regenerated PIN and prostatic adenocarcinoma lesions. Microarray analyses of transcriptional profiles showed more robust enrichment of known tumor and metastasis promoting genes: Spp1, Egr1, c-Myc, Sp5, and Sp6 genes in samples isolated from Ctnnb1^L(ex3)/+/R26hAR^L/+:PB-Cre4 compound mice than those from Ctnnb1^L(ex3)/+:PB-Cre4 and R26hAR^L/+:PB-Cre4 littermate controls. Together, these data demonstrate a confounding role of androgen signaling in β-catenin initiated oncogenic transformation in prostate tumorigenesis.

Molecular diagnostics of Drosophila suzukii (Diptera: Drosophilidae) Using PCR-RFLP

The invasive spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), has become a serious pest in the United States. Identification of immature and poorly preserved specimens can be difficult. A molecular diagnostic method for distinguishing D. suzukii from other Drosophila spp. associated with fruit in the United States was developed. A 709-bp region of the mitochondrial DNA cytochrome oxidase I gene was amplified from D. suzukii collections in the United States and compared with sequences of other Drosophila taxa from GenBank. Based on DNA sequence polymorphisms, a polymerase chain reaction-restriction fragment length polymorphism analysis using the restriction enzyme Msp-I was found to differentiate D. suzukii from other Drosophila spp. in the United States. This technique can identify field-collected specimens from various sources and specimens regardless of life stage. This molecular diagnostic method will be useful for monitoring the spread of this economically important invasive insect.

Attractiveness of an aggregation pheromone lure and chicken droppings to adults and larvae of Alphitobius diaperinus (Coleoptera: Tenebrionidae)

The chemical cues by which lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) beetles find each other are still unknown. Laboratory two-choice pitfall bioassays were conducted to evaluate the attractiveness of synthetic aggregation pheromone lure to lesser mealworm adults and larvae. All components of this synthetic aggregation pheromone lure, including: (R)-(+)-limonene, (E)-beta-ocimene, (S)-(+)-linalool, (R)-(+)-daucene, and 2-nonanone were also tested singly. Chicken dropping volatile compounds and fresh chicken droppings (CD) were evaluated singly or in combination with the pheromone lure. In Arkansas, trapping experiments were conducted in different poultry houses with low, moderate, and high lesser mealworm populations to evaluate the attraction of pheromone lure. Laboratory two-choice pitfall bioassay was found to be a useful and convenient tool for evaluating the attractants before testing them in the poultry house. Greater attraction of adults and larvae to a dose of 20-30 microg pheromone lure was identified in laboratory two-choice pitfall bioassays. Adults and larvae were highly attractive to a combination of fresh CD and pheromone lure, whereas, a combination of chicken dropping volatile and pheromone lure was not significantly attractive. The low attraction of limonene and linalool in the laboratory two-choice pitfall bioassays suggest that either they are nonattractive or attractive only at a narrow range of concentrations. Higher numbers of lesser mealworm adults and larvae were found in traps treated with pheromone lure as compared with untreated controls in field experiments. Results indicate a potential for combining the pheromone lure with the attractive CD compounds to enhance trap efficacy.

Ovavesicula popilliae (Microsporidia: Ovavesiculidae) spore production in naturally infected adult Japanese beetles (Coleoptera: Scarabaeidae)

Ovavesicula popilliae is a microsporidian that infects both Japanese beetle larvae and adults. This is the first study quantifying the number of O. popilliae spores produced by Japanese beetle adults. Mean spore production per adult Japanese beetle was 2.67 × 10(7) (SE ± 4.65 × 10(6)) spores with a range of 1.46 × 10(6)-1.02 × 10(8). The number of spores produced per host is similar to other microsporidian species and may help explain the speed with which this pathogen has spread from introduction sites to surrounding areas.

Survey of pathogens and parasitoids of Popillia japonica (Coleoptera: Scarabaeidae) in northwest Arkansas

The impact of pathogens and parasitoids on the recently established population of Popillia japonica Newman in northwest Arkansas has been unknown. In this study, we quantified the prevalence of natural enemies: Stictospora villani Hays, Ovavesicula popilliae Andreadis and Hanula, Paenibacillus spp. (Dingman), nematodes and parasitic Diptera and Hymenoptera in third instar and adult populations in 2010 and 2011. S. villani was found in 38.4% and 35.5% of larvae in 2010 and 2011, respectively. S. villani was not found in adult beetles. Paenibacillus bacteria were not found in either larvae or adults in either year. In 2010, the microsporidian O. popilliae was not found in larvae but was present in 0.2% of adults. In 2011, 2.6% of larvae were infected with O. popilliae, but the microsporidian was not found in adults. A previously unknown Adelina sp. was found infecting 0.4% of adult beetles in 2010 and 1.3% of larvae in 2011. Nematode infections were found in 1.8% of larvae and 0.1% of adults in 2010 and not found in either life stage in 2011. No parasitic Hymenoptera or Diptera were found in either year. Apparently, pathogens and parasitoids currently provide little control of the Japanese beetle population within northwest Arkansas.

Attractants for the green June beetle (Coleoptera: Scarabaeidae)

The purpose of this study was to develop and evaluate lures for adult green June beetles, Cotinis nitida (L.) (Coleoptera: Scarabaeidae), for future use in a mass trapping program. Volatile organic compounds collected from headspace of green June beetles feeding on fermenting ripe apple (Malus spp.), the natural lure that elicits feeding aggregations, were identified and confirmed by gas chromatography and mass spectrometry. Yellow funnel traps baited with 91% isopropanol or the five component blend were equally effective in eliciting aggregation behavior and often more attractive to green June beetles than the natural lure. In 2008, three trap lines adjacent and parallel to the perimeter of two vineyards, each with 12 Xpando yellow funnel traps baited with either 91% isopropanol or the five component blend, differed in catch of green June beetles across sample dates, and sample date by bait interaction but there were no differences among these two baits. A season total of 324,007 green June beetle were captured by these 36 baited traps. A brief review is included of fermentation volatiles attractive to insects. We conclude with the potential cost to use mass trapping against adult green June beetles.

Ovipositional preferences of the Japanese beetle (Coleoptera: Scarabaeidae) among warm- and cool-season turfgrass species

Japanese beetles, Popillia japonica Newman (Coleoptera: Scarabaeidae), were evaluated for ovipositional preferences among four turfgrasses common in northwestern Arkansas. Choice assays revealed females preferred to oviposit in tall fescue (Festuca arundinacea Schreb.) and zoysiagrass (Zoysia japonica Steud.), and that they avoided oviposition in common bermudagrass (Cynodon dactylon [L.] Pers.) and hybrid bermudagrass (C. dactylon x C. transvaalensis Pers.). Significantly fewer eggs were oviposited in hybrid bermudagrass in a no-choice assay, suggesting that chemical and/or physical plant characteristics deter oviposition in that grass. The percentage of turfgrass cores with evidence of female activity (presence of female or eggs, or signs of female digging) in choice assays revealed no differences among treatments, yet significantly fewer hybrid bermudagrass cores had eggs. These results suggest that many females did not initially reject hybrid bermudagrass based on aboveground plant characteristics, but rather they left without ovipositing. Therefore, resistance in hybrid bermudagrass is likely expressed below ground. Our results suggest that the use of hybrid bermudagrass as a means of cultural control in an integrated pest management program may discourage Japanese beetle oviposition and subsequent grub infestations in lawns, golf courses, or sports fields.

Transient solution to the bioheat equation and optimization for magnetic fluid hyperthermia treatment

Two finite concentric spherical regions were considered as the tissue model for magnetic fluid hyperthermia treatment. The inner sphere represents the diseased tissue containing magnetic particles that generate heat when an alternating magnetic field is applied. The outer sphere represents the healthy tissue. Blood perfusion effects are included in both the regions. Analytical and numerical solutions of the one-dimensional bioheat transfer equation were obtained with constant and spatially varying heat generation in the inner sphere. The numerical solution was found to be in good agreement with the analytical solution. In an ideal hyperthermia treatment, all the diseased tissues should be selectively heated without affecting any healthy tissue. The present work optimized the magnetic particle concentration in an attempt to achieve the ideal hyperthermia conditions. It was found that, for a fixed amount of magnetic particles, optimizing the magnetic particle distribution in the diseased tissue can significantly enhance the therapeutic temperature levels in the diseased tissue while maintaining the same level of heating in the healthy tissue.

Experiments on the role of gas height in the Rayleigh–Marangoni instability problem

Experimental evidence is provided to show the effect of gas phase dynamics on the onset of thermal convection and on the accompanying patterns in a silicone oil-air convecting bilayer. Very good agreement with three-dimensional calculations for linearized stability is obtained mostly for small and large gas heights. Reasons for this agreement as well as the results at intermediate gas heights are qualitatively explained from the perspective of well-established nonlinear analysis.

The Missouri planning grant for the education and training of health sciences librarians

The planning grant at the School of Library and Informational Science (SLIS) at the University of Missouri has two aims: (a) developing a model curriculum for health sciences librarianship at the master's level and (b) developing materials that can be delivered by alternative instructional methods. To accomplish the first aim, the faculty will investigate the possibility of offering courses in other disciplines, such as health care administration, educational technology, adult education, and medical sociology. In addition, the SLIS faculty will investigate the development of new kinds of placement for the students' practicum experience. To reach the second aim, the SLIS faculty will investigate alternative means of delivering both graduate and continuing education. Three instructional modalities will be evaluated. Some material will be delivered via satellite broadcast, some material will be made available via the World Wide Web and some will be presented in an intensive seminar. The outcome of the planning grant will be two distinct plans. The first will be a plan for the curriculum in health sciences librarianship at the master's level. The second will be a plan for offering instruction through alternative methods, both for graduate education and for continuing education.

Environmental risk factors for Lyme disease identified with geographic information systems

OBJECTIVES

A geographic information system was used to identify and locate residential environmental risk factors for Lyme disease.

METHODS

Data were obtained for 53 environmental variables at the residences of Lyme disease case patients in Baltimore County from 1989 through 1990 and compared with data for randomly selected addresses. A risk model was generated combining the geographic information system with logistic regression analysis. The model was validated by comparing the distribution of cases in 1991 with another group of randomly selected addresses.

RESULTS

In crude analyses, 11 environmental variables were associated with Lyme disease. In adjusted analyses, residence in forested areas (odds ratio [OR] = 3.7, 95% confidence interval [CI] = 1.2, 11.8), on specific soils (OR = 2.1, 95% CI = 1.0, 4.4), and in two regions of the county (OR = 3.5, 95% CI = 1.6, 7.4) (OR = 2.8, 95% CI = 1.0, 7.7) was associated with elevated risk of getting Lyme disease. Residence in highly developed regions was protective (OR = 0.3, 95% CI = 0.1, 1.0). The risk of Lyme disease in 1991 increased with risk categories defined from the 1989 through 1990 data.

CONCLUSIONS

Combining a geographic information system with epidemiologic methods can be used to rapidly identify risk factors of zoonotic disease over large areas.

Microcirculatory dynamics in experimental human gingivitis

The purpose of this study was to determine the changes that occur in the gingival microcirculation during the development of experimental gingivitis in humans. There have been no studies published to date combining videomicroscopy and laser Doppler flowmetry to study vascular dynamics in experimental gingivitis. Alterations occurring in the microcirculation of the marginal gingiva in 10 (18-30-year-old), healthy male humans when they suspended oral hygiene procedures in a proscribed area for 12-16 days were monitored. A partial mouth, experimental gingivitis model was employed. Gingival health was evaluated before and after the experimental period by assessing gingival and plaque indices and gingival crevicular fluid volume. Gingival vascular monitoring included measurement of red blood cell velocity in individual gingival microvessels via videomicroscopy and measurement of regional gingival blood flow using laser doppler flowmetry. The number of vessels visible in a given microscopic field in a given subject and the number of vessels exhibiting flow were also determined from the videotapes. Systemic cardiovascular and respiratory parameters were monitored to ensure that gingival vascular changes were not secondary to systemic changes. Gingivitis developed in all subjects; significant increases (Student t-test, p < 0.05) were seen in plaque index, gingival index, bleeding on probing and crevicular fluid volume. No change in superficial capillary blood velocity and a significant decrease in gingival regional blood flow were seen with gingivitis. A significant increase in the number of vessels visible in microscopic fields and a decrease in the % of vessels exhibiting flow were observed. Gingival microcirculation exhibited a dramatic, dynamic change in response to the development and progression of gingivitis.

Aging and microcirculatory dynamics in human gingiva

There have been no published reports characterizing gingival vascular function in humans of different ages. In this study, we compared gingival vascular dynamics in 60 healthy male humans ranging in age from 18-75 years (young, 18-25 years (Y); middle, 35-45 years (M); old, 65-75 years (O), 20 subjects/group). Both videomicroscopy of individual microvessels and laser doppler flowmetry were employed to assess marginal gingival circulation. Systemic cardiopulmonary parameters were monitored as controls. The number of gingival vessels visible in a microscopic field was higher and the number of microvessels exhibiting active flow was lower in M and O compared to Y. There were no differences among age groups in laser doppler flow values (tissue blood flow) or in red blood cell velocity in individual vessels. Although not statistically significant with age there was a trend towards decreasing blood flow velocity in both the laser doppler and videomicroscopic measurements. Blood pressure increased slightly with age. Peripheral oxygen saturation was lower in O compared to Y and M. No differences were seen in heart rate, respiratory rate or end-tidal carbon dioxide concentration. The changes in blood pressure and oxygen saturation were expected. The differences in numbers of visible vessels and the number of vessels with active blood flow may reflect the way the gingival microcirculation adapts with age to changing nutritional needs or to microbial and/or mechanical challenge.

Diagnosis of a mass in the neck

A mass in the neck can occur because of developmental factors, lymphadenopathy, salivary gland disease, or neuromas. It is important to examine areas other than the neck in assessing these masses, most of which can be diagnosed by a good history/physical examination and simple laboratory tests, described here.

The interpretative validity of the FAM: long-term psychotherapists' ratings of psychiatric inpatients

Newmark, Conger, and Faschingbauer (1976) found a significant difference between mean ratings of MMPI and FAM (Faschingbauer's Abbreviated MMPI) based interpretations. Since this may have been specific to lack of rater experience, the present study attempted a replication using long-term psychotherapists as raters. The only significant difference was for 20 male psychiatric inpatients. Females (n = 16) and the pooled sample showed no significant differences between ratings regardless of the source test. When the present results are compared to those of Newmark, Conger and Faschinbauer (1976) and earlier work by Fashcinbauer (1973), it appears that the FAM yields interpretation as accurate as one would expect given its psychometric dissimilarity from the MMPI.

Effect of time-specific sets and patients' personality style on state and trait anxiety

60 subjects representing equal numbers of repressors arid sensitizers were matched for age and sex and evaluated on three measures of anxiety which differed in time span in which anxiety was estimated. As expected, sensitizers reported significantly greater anxiety than repressors regardless of the proximity of the time on which they based their estimates. A significant interaction between reports of anxiety and repression-sensitization demonstrated that sensitizers report less anxiety when recording their current condition than remote remembrances, whereas repressors tend to report essentially the same level of anxiety regardless of whether they are estimating their anxiety over “a year or two,” “a month or two,” or “now.”

MMPI correlates of extreme field independence and field dependence in a psychiatric population

34 male and 34 female hospitalized psychiatric patients were divided into field-independent and field-dependent groups on the basis of rod-and-frame test performance and their MMPI scores were compared. A multiple discriminant analysis followed by a series of 2 X 2 factorial analyses of variance was used to assess the results. As in previous studies, more similarities than differences were found between the two cognitive styles. However, field-independent subjects tended to be more unconventional, aggressive, antisocial, and perhaps defensive than field-dependent subjects. Explanations of results were explored in reference to previous findings.

Effects of birth order and sex on field independence-dependence

Birth order and field-independence research has produced seemingly similar findings concerning social dependence. However, of the few empirical efforts examining such similarities, methodological differences have produced ambiguous findings. The effects of sex and three birth-order categories on Rod-and-frame scores were evaluated for 248 male and 389 female psychiatric inpatients. A 2 × 3 analysis of variance showed significant sex and birth-order effects, with males and firstborns less field-dependent than females and both later-borns and only children, respectively. The unpredicted birth-order results essentially contradicted previous findings and were discussed in terms of sample differences and the apparent need for improved social-dependency measures.