Oral vaccination of dogs with a monovalent live-avirulent vaccine confers 1 year of immunity against Bordetella bronchiseptica challenge.

This experimental challenge study assessed immune protection 1 year after a single dose of live-attenuated oral Bordetella bronchiseptica (Bb) vaccine in dogs. Forty Bb-seronegative 7-9-week-old puppies were randomly assigned at Day 0 to receive a single oral dose of either Bb vaccine (n = 20; vaccinated group) or sterile water (n = 20; control group). Groups were housed separately until comingling 1 day pre-challenge (Day 365). Challenge with virulent aerosolized Bb occurred at Day 366. Clinical scores were obtained at Days 1-7, and 366-380. Bb microagglutination test (MAT) titers were obtained at Days -7, 0, monthly post-vaccination, and Days 358, 365, and 380. Nasal swabs were collected for microbiological assessment at Days -7, 0, 365, and 367-380. Oral Bb vaccination was not associated with side effects. Pre-challenge, vaccinated dogs developed persistent Bb MAT titers and control dogs remained seronegative. Post-challenge, duration of cough was longer in control dogs (least square means [LSM], 8.6 days) than vaccinated dogs (LSM, 1.5 days; P < 0.0001), with more control dogs having cough on 2 or more consecutive days (control group, n = 17/19, 89.5%; vaccinated group, n = 3/19, 15.8%; P = 0.0011). Post-challenge, Bb shedding occurred in all control dogs and 5/19 (26%) vaccinated dogs. Average duration of Bb shedding was longer in the control group (11.9 days vs. 0.6 days; P < 0.0001) and nasal Bb loads were higher in the control group (P < 0.00001). Orally administered Bb vaccine stimulated immunity that was still protective against virulent Bb challenge after 1 year.

Rapid diagnosis of acute norovirus-associated gastroenteritis: evaluation of the Xpert Norovirus assay and its implementation as a 24/7 service in three hospitals in Jönköping County, Sweden.

Noroviruses are a leading cause of epidemic and sporadic cases of acute gastroenteritis worldwide. The rapid diagnosis of norovirus infection is important for prompt infection control measures and may reduce the need for additional diagnostic testing. Here we evaluated the performance of the rapid Xpert Norovirus assay, and assessed the turn-around time (TAT) before and after the implementation of the analysis as a 24/7 service at all the three hospitals in Jönköping County, Sweden. We describe the implementation process which was performed in two steps during 2014. A total number of 276 clinical samples (stool and vomitus) from patients with symptoms of acute gastroenteritis were included in 2014-2015. The samples were analysed with the Xpert Norovirus assay and the already existing routine method: an in-house reverse transcription real-time PCR. Samples showing discrepant results with the two assays were further analysed by a third PCR method. The Xpert Norovirus assay performed well with a sensitivity of 100% and a specificity of 93% compared to the gold standard (defined as the result obtained by at least two of the three PCR methods). The median TAT decreased from 22 hours in 2013 to 2.4 hours in 2015 (p<0.001). We conclude that the performance of the Xpert Norovirus assay was excellent, and that the implementation of the analysis as a 24/7 service at all three hospitals in the county has greatly reduced the time to diagnosis which is beneficial for both patients and healthcare providers.

Comparative efficacy of intranasal and oral vaccines against Bordetella bronchiseptica in dogs.

In order to determine the comparative efficacy of vaccines administered intranasally or orally to protect puppies from disease subsequent to experimental infection with Bordetella bronchiseptica (Bb), a randomized controlled trial was performed using 48 approximately 8-week-old specific pathogen free, Bb naive Beagle puppies. Puppies were randomized into three groups and administered vaccines containing Bb intranasally or orally, or a placebo intranasally. Twenty-one days later, all dogs were challenge exposed via aerosol administration of Bb. Clinical signs, nasal bacterial shedding and immune responses were monitored for 28 days after challenge. Intranasally vaccinated puppies had significantly lower rates of coughing, nasal discharge, retching and sneezing (i.e. were less sick clinically) than control puppies. The distinction between the orally vaccinated puppies and the control puppies was less consistent. The orally vaccinated puppies had less coughing and less retching than the control puppies, but nasal discharge and sneezing did not differ from control animals. Orally vaccinated puppies had higher rates of coughing, nasal discharge, retching and sneezing than the intranasally vaccinated puppies. Although both intranasal and oral Bb vaccines stimulated immune responses associated with disease sparing following Bb infection, the intranasal route of delivery conferred superior clinical outcomes. The observed difference in clinical efficacy suggests the need to question the rationale for the use of currently available orally administered Bb vaccines.

Time-frequency analysis of the EEG mu rhythm as a measure of sensorimotor integration in the later stages of swallowing.

OBJECTIVE: Electroencephalography (EEG) was used to map the temporal dynamics of sensorimotor integration relative to the strength and timing of muscular activity during swallowing. METHODS: 64-channel EEG data and surface electromyographic (sEMG) data were recorded from 25 neurologically-healthy adults during swallowing and tongue-tapping. Events were demarcated so that sensorimotor activity primarily from the pharyngeal and esophageal phases of swallowing could be compared to activity resulting from tongue tapping. RESULTS: Independent component analysis identified bilateral clusters of sensorimotor mu components localized to the premotor and primary motor cortices as well as an infrahyoid myogenic cluster. Subsequent event-related spectral perturbations (ERSP) analyses showed event-related desynchronization (ERD) in the spectral power in the alpha (8-13Hz) and beta (15-25Hz) frequency bands of the mu clusters in both tasks. Mu ERD was stronger during swallowing when compared to tongue tapping (pFDR<.05) and the differences in sensorimotor processing between conditions was greater in the right hemisphere than the left, suggesting stronger right hemisphere lateralization for swallowing than tongue-tapping. CONCLUSION: Mu activity was interpreted as representing a normal feed forward and feedback driven sensorimotor loop during the later stages of swallowing. SIGNIFICANCE: Results support further use of this novel neuroimaging technique to concurrently map neural and muscle activity during swallowing in clinical populations using EEG.

Optimal haematocrit in subjects with normal haemoglobin genotype (HbAA), sickle cell trait (HbAS), and homozygous sickle cell disease (HbSS).

The determination of an optimal haematocrit (H0) has important clinical implications if such a level can be attained, and more importantly, maintained. This is defined as a haematocrit level, above or below which oxygen delivery is deleteriously affected. This study is designed to determine an optimal haematocrit in normal (AA), sickle cell trait (AS) and sickle cell disease (SS) subjects. Twenty-seven apparently healthy subjects having normal haemoglobin genotype, 24 with sickle cell trait and 42 with homozygous sickle cell disease were recruited into the study. Whole blood viscosity (WBV) was measured by a Wells Brookfield Cone and Plate Viscometer at a shear rate of 230 sec-1. Haematocrit was determined by an AC.Tron Coulter Counter. The optimal haematocrit was calculated as the inverse of a constant, K, which was derived from the haematocrit and viscosity data. Our findings showed that the H0 varied significantly among the 3 haemoglobin genotypes, in the order AA vs SS and AS vs SS. Additionally, the data indicated an increased H0 in subjects with sickle cell trait, suggesting a possible impairment in oxygen delivery in these individuals.

Oxygen delivery index in homozygous sickle cell disease: steady and crisis states.

One of the common complications of sickle cell disease is the vaso-occlusive crisis or sickle cell crisis which could result in impaired oxygen delivery to the tissues. This study investigates the oxygen delivery index (ODI) in 38 patients with homozygous sickle cell anaemia. Thirty-three patients were in the steady state and five were experiencing crisis at the time of recruitment. Whole blood viscosity was measured with a Wells Brookfield viscometer at a shear rate of 230 sec(-1) and haematocrit was measured with an AC Tron Coulter Counter. The ODI, which is an indirect measure of the capacity of blood to deliver oxygen to tissues, was calculated as the ratio of haematocrit to whole blood viscosity values. There was no statistically significant difference in the ODI between the steady and crisis states, suggesting that tissue oxygenation is not the only factor involved in the sickle cell crisis.

Oxygen delivery index in subjects with normal haemoglobin (HbAA), sickle cell trait (HbAS) and homozygous sickle cell disease (HbSS).

Sickle cell disease is characterized by altered blood rheology due to a reduced haematocrit and a resulting lowered viscosity. Oxygen carriage, and consequently oxygen delivery, may be deleteriously affected if the haematocrit reduction is such as to limit oxygen uptake from the lungs and delivery to the tissues. The present study seeks to determine and compare the oxygen delivery index (ODI) in subjects with normal and abnormal haemoglobin genotypes. Thirty four apparently healthy subjects having normal haemoglobin genotype (AA), 27 with sickle cell trait (AS) and 50 with homozygous sickle cell disease (SS) were recruited into the study. Whole blood viscosity was measured at low and high shear rates of 23 s(-1) and 230 s(-1), respectively, using a Wells Brookfield Cone and Plate Viscometer. Haematocrit was determined using an AC.Tron Coulter Counter. The oxygen delivery index was calculated as the ratio of the haematocrit to whole blood viscosity. There was a statistically significant difference in the ODI in the SS group compared with both the AA and AS groups. There was no statistical significance in the ODI between the AA and AS groups. The ODI may be considered as a useful assessment of oxygen delivery in subjects with sickle cell disease.

An unusual cause of hyperinsulinaemic hypoglycaemia syndrome.

Endogenous hyperinsulinism as a cause for hypoglycaemia can be attributed to a number of different causes including insulinoma, sulphonylurea drugs and the newly described disorder non-insulinoma pancreatogenous hypoglycaemia (NIPH). The calcium stimulation test is increasingly used as a method for not only localizing insulinoma but also for distinguishing the above entities. We describe a case in which felonious sulphonylurea administration was used to mimic either an insulinoma or NIPH. Importantly, this case demonstrates that, contrary to previous reports, the insulin response to calcium stimulation in such cases may be uniformly positive and should alert the physician to possible surreptitious sulphonylurea ingestion.

Gas phase reduction of chlorinated VOCs by zero valent iron.

The removal of trichloroethylene (TCE) by reduction with elemental iron was examined in batch reactors representing three phase gaseous systems (Fe0 (solid), water vapor + TCE vapor + air mixture (gaseous), and condensed water on Fe0 surface (aqueous)) and two phase aqueous systems (Fe0 (solid), water (aqueous)) as the reaction medium. Two separate removal mechanisms were found for TCE removal in the gas phase reactors: (1) adsorption onto the Fe0 surface under low relative humidity (RH), and (2) reaction with Fe0 to form other organic compounds, such as ethylene, isomers of dichloroethylene, and vinyl chloride under 100% RH conditions in the gas phase. The adsorption of TCE vapor onto the Fe0 surface was fast initially and highest at low temperatures. The reduction reaction of TCE in the gas phase was first order with respect to the TCE concentration remaining in the gas phase under conditions of 100% RH at 15, 22, and 35 degrees C, and the observed reaction rate constant (kobs) exhibited a maximum at elevated temperatures. The estimated kobs values for the degradation of dissolved TCE in aqueous systems were the same order of magnitude with the rate constants in the gas phase and exhibited an increasing rate at higher temperatures. The results suggest that Fe0 represents an economical choice for vapor phase barriers to limit the spread of contaminants in soil gas and reduce fugitive air emissions from contaminated sites.

Comparison of methods for estimating carbonaceous BOD parameters.

The performance of seven different methods (Differential, Fujimoto, Thomas, Graphical, Integral, Log-Difference, and Nonlinear Regression) for estimating first-stage, carbonaceous biochemical oxygen demand (CBOD), curve parameters, namely k and L0, were compared using synthetic data generated by Monte Carlo simulation technique. The comparison of the methods was made based on their efficiency in retrieving the original values of k and L0, which were selected to generate the synthetic data. In the first part of the study, five sets of "true" data (without error substitution) with different k and L0 value pairs, (k (d(-1))-L0 (mg l(-1)): 0.23-10,000; 0.23-250; 0.23-50; 0.10-250; and 0.50-250) were used to obtain information about the effect of different k-L0 combinations and of using 5-day and 20-day CBOD data on the performance of the methods. In the second part, the same methods were used to calculate k and L0 for ten sets of synthetic data with log-normally distributed random errors at the coefficient of variation (COV) levels of 0.1, 0.2, and 0.3 for a single k-L0 value pair, (0.23 d(-1); 250 mg l(-1)). The results indicated that: (1) different combinations of k-L0 values had no significant effect on the performance of CBOD curve parameter estimation methods with the "true" data; (2) use of CBOD20 data, i.e., CBOD data collected for 20 days, provided better estimates for k and L0; (3) the Integral and Nonlinear Regression techniques were found to be the most reliable methods for the estimation of CBOD curve parameters among the other methods considered in this study.

Eye movements and reading with large print and optical magnifiers in macular disease.

PURPOSE: Reading rate has been the main performance measure in studies that have compared reading with large print and optical magnifiers; eye movement characteristics have not been considered. We compared both eye movement characteristics and reading rates for subjects with macular disease reading without and with a range of low-vision devices. METHODS: Silent reading rate and eye movement characteristics for text passages at critical print size of 21 subjects aged 14 to 88 years with macular disease were measured with and without their preferred low-vision device. Saccadic frequency was determined from a sequencing task comprising five letters each separated by 5 degrees. Eye movements were recorded using an infrared limbal reflection system. RESULTS: There were no significant differences in reading rate, fixation durations, saccade numbers per word, or percent retrace time when using a low-vision device compared with reading without a low-vision device. The percentage of regressions was, however, lower with the low-vision device. Saccadic frequency in the sequencing task was predictive of reading performance with and without a low-vision device. CONCLUSIONS: When reading at critical print size, in terms of reading rate or saccades per word, there was no advantage to using large print over an optical low-vision device.

Oral and silent reading performance with macular degeneration.

Previous studies have shown that reading rate for very large print (6 degrees, 1.86 logMAR character size) is a strong predictor of oral reading rate with low vision devices (LVDs). We investigated whether this would apply using large print sizes more readily available in clinical situations (e.g. 2 degrees, 1.4 logMAR), for subjects with macular degeneration. We assessed rauding rates--reading for understanding. A combination of near word visual acuity and large print reading rate (without LVDs) provided the best prediction of oral rauding rates (with LVDs). However, near word visual acuity alone was almost as good. Similarly, silent rauding rate was predicted best by near word visual acuity alone. We give near visual acuity limits as a clinical guide to expected oral and silent reading performance with LVDs for patients with macular degeneration.

Eye movements and reading with plus-lens magnifiers.

PURPOSE: This study aimed to determine the eye movement parameter(s) that is primarily affected when fully sighted subjects use plus-lens magnifiers for reading. METHODS: Two forms of plus-lens magnifier were used: hand-held and spectacle-mounted. Eye movements were recorded using an infrared limbal reflection system as subjects read passages of text with and without the magnifiers. Data were compared for a young age group and an elderly (education-matched) age group. RESULTS: For both age groups, a sawtooth pattern of eye movements was observed and reading speed was significantly (p = 0.0001) reduced when using the magnifiers compared with reading without. Forward saccade length decreased significantly (p = 0.0001) and time for retrace increased significantly (p = 0.0001), but fixation durations were unaffected. The form of magnifier had no significant effect on reading speed or eye movement parameters. CONCLUSIONS: The reduction in reading speed that occurred when using the plus-lens magnifiers was primarily a result of decreased forward saccade length.

Phytophotodermatitis.

This article is a concise review of phytophotodermatitis, including the mechanism involved, clinical features, and treatment options. The common culprit plant families of Umbelliferae, Rutaceae, and Moraceae are discussed along with the newly recognized St. John's Wort.

Analysis of site-specific phosphorylation of the retinoblastoma protein during cell cycle progression.

Differential phosphorylation of the retinoblastoma protein plays a pivotal role in cell cycle regulation. The retinoblastoma protein is specifically phosphorylated during the cell cycle by cyclin-dependent kinase complexes which intersect with many cellular signaling networks. Since the loss of the retinoblastoma signaling pathways occurs in a wide variety of human tumors, understanding the significance of site-specific phosphorylation can clarify the role of selected cyclin-dependent kinase complexes during cell cycle progression. Here we describe the phosphospecificity and cellular characterization of a panel of polyclonal antibodies that recognize unique phosphorylation sites within the retinoblastoma protein. These reagents were used to validate authentic cellular retinoblastoma phosphorylation sites at amino acids 780, 795, and 807/811 correlating with the G1-S transition.

Visual circuits of the avian telencephalon: evolutionary implications.

Birds and primates are vertebrates that possess the most advanced, efficient visual systems. Although lineages leading to these two classes were separated about 300 million years ago, there are striking similarities in their underlying neural mechanisms for visual processing. This paper discusses such similarities with special emphasis on the visual circuits in the avian telencephalon. These similarities include: (1) the existence of two parallel visual pathways and their distinct telencephalic targets, (2) anatomical and functional segregation within the visual pathways, (3) laminar organization of the telencephalic targets of the pathways (e.g. striate cortex in primates), and (4) possible interactions between multiple visual areas. Additional extensive analyses are necessary to determine whether these similarities are due to inheritance from a common ancestral stock or the consequences of convergent evolution based on adaptive response to similar selective pressures. Nevertheless, such a comparison is important to identify the general and specific principles of visual processing in amniotes (reptiles, birds, and mammals). Furthermore, these principles in turn will provide a critical foundation for understanding the evolution of the brain in amniotes.

Word and tone working memory deficits in schizophrenia.

BACKGROUND: Verbal memory deficits have been reported in many studies of patients with schizophrenia. We evaluated the specificity of these deficits by comparing patients and control subjects on several verbal and nonverbal auditory memory tests. METHODS: Performance of stable, medicated outpatients with DSM-III-R diagnoses of schizophrenia (N = 38) was compared with that of healthy subjects (N = 39) on a word list immediate recall task, tone delayed discrimination tasks, and word and tone serial position tasks. Before memory testing, patients were divided into 2 groups based on their ability to perform normally on a screening test requiring pitch discrimination and sustained attention. RESULTS: The nonverbal tests were more difficult for control subjects than the verbal tests. Despite this, patients who performed normally on the screening test of perception and attention performed normally on both nonverbal tests but had highly significant deficits on both verbal tests (P<.001 and P = .02). Patients who performed poorly on the screening test had highly significant performance deficits on all the memory tests. CONCLUSIONS: One subgroup of patients with schizophrenia has a selective deficit in verbal memory despite normal motivation, attention, and general perceptual function. Another group has deficits in multiple aspects of cognitive function suggestive of failure in early stages of information processing.

Functional MR imaging of regional brain responses to pleasant and unpleasant odors.

BACKGROUND AND PURPOSE: Odors can elicit a range of behaviors and emotions. Our purpose was to identify regional activation of the human cerebral cortex in response to pleasant (positive hedonic value) and unpleasant (negative hedonic value) odors. METHODS: Thirteen neurologically normal adults underwent functional MR imaging of frontal and anterior temporal brain regions with a gradient-echo echo-planar technique. Eleven candidate regions of interest (ROIs) were identified on the first half of the data set based on t-map comparisons of signal intensities during administration of clementine (pleasant odor), isovaleric acid (unpleasant odor), and clear air (control odor). These ROIs were applied to the second half of the data set, and the number of voxels activated with the odorants was compared with the number of voxels activated during clear air trials, using independent t-tests. RESULTS: Clementine activated five cortical areas: Brodmann's area (BA) 8, BA 32 (lateralized to left), BA 46/9, BA 6 (lateralized to right), and the insula. Isovaleric acid activated four of the five regions without lateralization; no BA 8 activity was seen. Clementine produced more activity than isovaleric acid in the left insula, and isovaleric acid produced more activity than clementine in the left BA 6. No activation was detected in the orbitofrontal cortex or in the medial temporal lobes. Subjects rated clementine, isovaleric acid, and clear air as being pleasant, unpleasant, and neutral, respectively. CONCLUSION: Activation in frontal regions may represent brain processes linked to olfactory networks. There may be regional specialization based on odorant hedonic values.

Eye movements and reading with simulated visual impairment.

The purpose of this study was to investigate the effects of simulated visual impairment on the reading speed and reading eye movements of young, normally-sighted observers. Afocal diffusing filters (Ryser occlusion foils) were used to create three levels of impairment and eye movements were recorded using a spectacle-mounted, infra-red limbal reflection system. Reading speed decreased significantly (P < 0.01) as the level of impairment increased. Eye movement analysis revealed the main contributory factors to be increased fixation durations, shorter saccades (resulting in increased numbers of forward saccades per line) and, to a lesser extent, increased time required for page navigation. The results suggest that in order to achieve optimal reading speeds, print size should be at least four times the acuity threshold and that print contrast should be at least twenty times contrast threshold.