Effect of sorghum resistant to Stenodiplosis sorghicola (Coquillett) (Diptera: Cecidomyiidae) on oviposition and development of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Abstract Helicoverpa armigera oviposition preference for, and larval development on sorghum hybrids with differing resistance to sorghum midge, Stenodiplosis sorghicola , were investigated. When H. armigera larvae were fed seed of resistant and susceptible hybrids in the laboratory there were no differences in larval and pupal sizes or the rate of development. The same result was recorded when larvae fed on panicles on plants in a glasshouse. On some sampling occasions, significantly more eggs were laid on panicles of resistant hybrids in the field. This occurred when plants were in plots and also in a mixed planting. Midge-resistance status did not affect levels of egg parasitism. In a field study using recombinant inbred lines between a midge-resistant and a midge-susceptible line, no relationship was found between level of resistance and oviposition of H. armigera . We conclude that, although midge-resistant hybrids are sometimes preferred for oviposition by H. armigera, the resistance per se does not determine this preference. Egg survival, larval survival, development and resultant damage are not significantly affected by the midge-resistance status of the host.     

Morphogenesis of the respiratory bronchiole in rhesus monkey lungs

The epithelium of the respiratory bronchiole in the adult rhesus monkey consists of two populations: a pseudostratified epithelium with basal, mucous goblet, and ciliated cells located near the pulmonary artery (PA); and a simple cuboidal epithelium composed only of nonciliated bronchiolar epithelial (or Clara) cells in areas away from the PA. This study describes the pattern of differentiation of these two epithelial populations, and their relationship to the PA and to the time of appearance of alveoli in the respiratory bronchiole of the rhesus monkey during the period of 90-125 days gestational age (DGA). These events were related to changes in the adjacent parenchyma. Dissected airways of infusion-fixed, critical-point-dried lungs were evaluated by scanning microscopy followed by light microscopy of the same airways. At 54% of gestation (90 DGA), the distal airway was lined by a mixture of ciliated and nonciliated cells. By 67% of gestation (110 DGA), the ciliated cells were confined to the epithelium over the PA. The underlying connective tissue initially was cellular containing few fibers but was fibrous by 76% of gestation (125 DGA). Alveolarization began near the most distal cartilage at 57% of gestation (95 DGA), the same period at which secondary septation occurred in the distal acinus. Thus, alveolarization occurred simultaneously in two centers: 1) the proximal centriacinar region in the vicinity of the most distal cartilage and 2) the distal lung parenchyma. The duration of centriacinar alveolarization was short, approximately 5 days.     

Expiration rate drives human airway design

Analyses of human airway architecture based on calculations of airflow resistance or energy dissipation suggest that the branching pattern is not optimized for minimizing energy loss by flow dissipation during respiration. Airway flow dissipates only a few percent of the total body work during normal breathing, so branching patterns deviate from minimum energy loss to also optimize other physiological needs. Studies of airway performance often record some measure of expiration, such as FEV1 (Forced Expiratory Volume in 1 s), because airway constriction during expiration limits the rate of rapid respiration. We posit that lung structure is optimized for the rate of expiration as well as minimum energy loss. By increasing the daughter-to-parent airway diameter ratio (h) from 0.794 (corresponding to the energy minimum for symmetrically branching airways) to 0.85 (the observed value in humans) luminal pressures at airway generations 4-15 were substantially increased during exercise (a 4.5 and 15 cmH₂O increase during moderate and heavy exercise, respectively). Values of h somewhat larger than 0.794 help airways remain open during expiration by increasing both viscous pressure drop and convective acceleration pressure drop. Asymmetric bifurcations also exhibit higher proximal airway pressures than symmetric ones, but the improvement was not large.     

Regional differences in quantities of histochemically detectable mucosubstances in nasal, paranasal, and nasopharyngeal epithelium of the bonnet monkey

Inhaled irritants induce secretory cell hyperplasia in nasal epithelium of animals. To characterize this response histochemically it is first important to know the histochemical character and distribution of epithelial mucosubstance in the normal nasal cavity. An automated image analyzing method was used to detect and quantitate acidic, neutral, and sulfated mucosubstances in the epithelium lining the nasal and paranasal airways of eight bonnet monkeys. Tissue sections 2 micron thick from defined regions of these airways were stained with either alcian blue/periodic acid-Schiff to demonstrate acid and neutral mucosubstances or high iron diamine to demonstrate sulfated mucins. Respiratory epithelium covering maxilloturbinates had the largest volume of stainable mucosubstance per unit surface area of basal lamina, whereas the maxillary sinus epithelium had the least. There was a general anteroposterior increase in the quantity of total epithelial mucosubstance along the septal and lateral walls of the nasal cavity, and there was more acidic than neutral mucosubstance in the posterior nasal airway than in the anterior. Epithelial mucosubstance in the maxillary sinus was predominantly neutral. Therefore, we conclude that there are substantial regional quantitative differences in stainable mucosubstances in the primate nasal epithelium which must be considered when examining nasal mucosa for irritant-induced changes in epithelial mucins.     

Extraction of [14C] vitamin A from rat liver and kidney during processing for transmission electron microscopy.

The retention of radioisotope-labeled vitamin A during processing for electron microscopy was investigated using the livers and kidneys of vitamin A deficient rats. [15-14C]Retinol (3muCi/animal) was administered by esophageal intubation to male rats which had been maintained on a vitamin A deficient diet for five or six weeks postweaning. Glutaraldehyde- or osmium-fixed tissue was processed by three methods: a) routine (a graded series of ethanols, propylene oxide and epoxy), b) rapid (75% and 95% ethanol with three changes of epoxy), or c) water-soluble embedding (70% and 80% hydroxypropyl methacrylate). Water-soluble embedding retained the highest percentage of label in the tissue (liver: 96.31%; kidney: 98.68%). Inclusion of osmium tetroxide in the processing sequence and minimal exposure of tissue to lipid solvents were necessary for good retention of labeled vitamin A in tissues.     

Temporal and spatial distribution of ciliogenesis in the tracheobronchial airways of mice

Little is known about ciliogenesis as it proceeds through the entire airway tree, from the trachea to the terminal bronchioles, especially during the postnatal period. The purpose of this study was to define the spatial and temporal (prenatal and postnatal) pattern of normal cilia development in the mouse. Three airway generations representing the entire airway tree were examined: trachea, lobar bronchi, and terminal bronchiole. Ciliated cells in lung lobe whole mounts were labeled with a fluorescent dye for confocal microscopy, and ciliated cell surface density was measured for each airway generation and age. The same samples were examined by scanning electron microscopy to verify the appearance of ciliated cells among the differentiating epithelium of the airways. Ciliated cells were first detected in the trachea and lobar bronchi at 16 days gestational age (DGA) and in the terminal bronchioles at 18 DGA. Ciliated cell surface density increased with prenatal and postnatal age at all airway levels. However, the ciliated cell surface density of the trachea and lobar bronchi was always greater compared with the terminal bronchiole. In conclusion, the study revealed that in developing tracheobronchial airways of the mouse: 1) Ciliogenesis differs temporally and spatially by airway generation; 2) Ciliated cell surface density increases with age in all airway generations, but density decreases in a proximal to distal direction; and 3) A significant portion of ciliogenesis continues after birth. This study provides a healthy basis for investigations of neonatal pulmonary disease or pollutant toxicity affecting cilia and its functions.     

Selecting high-dimensional mixed graphical models using minimal AIC or BIC forests

Background  

Chow and Liu showed that the maximum likelihood tree for multivariate discrete distributions may be found using a maximum weight spanning tree algorithm, for example Kruskal's algorithm. The efficiency of the algorithm makes it tractable for high-dimensional problems.     

Does small-sided-games’ court area influence metabolic,perceptual, and physical performance parameters of young elite basketball players?

The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size.     

An IGF-I promoter polymorphism modifies the relationships between birth weight and risk factors for cardiovascular disease and diabetes at age 36

BACKGROUND: Biochemical testing for pheochromocytoma by measurement of fractionated plasma metanephrines is limited by false positive rates of up to 18% in people without known genetic predisposition to the disease. The plasma normetanephrine fraction is responsible for most false positives and plasma normetanephrine increases with age. The objective of this study was to determine if we could improve the specificity of fractionated plasma measurements, by statistically adjusting for age. METHODS: An age-adjusted metanephrine score was derived using logistic regression from 343 subjects (including 33 people with pheochromocytoma) who underwent fractionated plasma metanephrine measurements as part of investigations for suspected pheochromocytoma at Mayo Clinic Rochester (derivation set). The performance of the age-adjusted score was validated in a dataset of 158 subjects (including patients 23 with pheochromocytoma) that underwent measurements of fractionated plasma metanephrines at Mayo Clinic the following year (validation dataset). None of the participants in the validation dataset had known genetic predisposition to pheochromocytoma. RESULTS: The sensitivity of the age-adjusted metanephrine score was the same as that of traditional interpretation of fractionated plasma metanephrine measurements, yielding a sensitivity of 100% (23/23, 95% confidence interval [CI] 85.7%, 100%). However, the false positive rate with traditional interpretation of fractionated plasma metanephrine measurements was 16.3% (22/135, 95% CI, 11.0%, 23.4%) and that of the age-adjusted score was significantly lower at 3.0% (4/135, 95% CI, 1.2%, 7.4%) (p < 0.001 using McNemar's test). CONCLUSION: An adjustment for age in the interpretation of results of fractionated plasma metanephrines may significantly decrease false positives when using this test to exclude sporadic pheochromocytoma. Such improvements in false positive rate may result in savings of expenditures related to confirmatory imaging.