Pathogenesis of New Strains of Newcastle Disease Virus From Israel and Pakistan.

In the past few years, Newcastle disease virus (NDV) strains with epizootic characteristics belonging to subgenotypes VIIi and XIIIb emerged in the Middle East and Asia. In this study, 2 NDV strains-1 representative of subgenotype VIIi isolated in Israel (Kvuzat/13) and 1 representative of subgenotype XIIIb isolated in Pakistan (Karachi/07)-were characterized by intracerebral pathogenicity index and detailed clinicopathologic assessment. The intracerebral pathogenicity index values for Kvuzat/13 and Karachi/07 were 1.89 and 1.85, respectively, classifying these strains as virulent by international standards. In 4-week-old White Leghorn chickens, both strains caused 100% mortality within 4 (Kvuzat/13) and 5 (Karachi/07) days postinfection. Histopathology and immunohistochemistry for NDV nucleoprotein showed that both strains had wide systemic distribution, especially targeting lymphoid organs and mucosa-associated lymphoid tissues in the respiratory and intestinal tracts. Results of the animal experiment confirm that both Kvuzat/13 and Karachi/07 are highly virulent and behaved as velogenic viscerotropic NDV strains.

The relationship between physical activity, structural deformity, and spinal mobility in adolescent idiopathic scoliosis patients.

PURPOSE: Adolescent idiopathic scoliosis (AIS) patients experience structural spinal deformity, but the impact of AIS on physical activity is not widely studied. Reports of physical activity levels between children with AIS and their peers are mixed. This study sought to characterize the relationship between spinal deformity, spinal range of motion, and self-reported physical activity in AIS patients. METHODS: Patients aged 11-21 completed self-reported measures of physical activity using the HSS Pedi-FABS and PROMIS Physical Activity questionnaires. Radiographic measures were obtained from standing biplanar radiographic imaging. Surface topographic (ST) imaging data was obtained using a whole-body ST scanning system. Hierarchical linear regression models analyzed the relationship between physical activity, ST, and radiographic deformity while controlling for age and BMI. RESULTS: 149 patients with AIS (mean age 14.5 ± 2.0 years, mean Cobb angle 39.7° ± 18.9°) were included. In the hierarchical regression predicting physical activity from Cobb angle, no factors were significant predictors of physical activity. When predicting physical activity from ST ROM measurements, age and BMI served as covariates. No covariates or ST ROM measurements were significant predictors of physical activity levels for either activity measure. CONCLUSIONS: Physical activity levels of patients with AIS were not predicted by levels of radiographic deformity or surface topographic range of motion. Although patients may experience severe structural deformity and range of motion limitations, these factors do not appear to be associated with decreased physical activity level utilizing validated patient activity questionnaires. LEVEL OF EVIDENCE: Level II.

Does improved radiographic alignment truly enhance dynamic functional balance?

Prospective, concurrent-cohort study. To establish the relationship between radiographic alignment parameters and functional CoE measurements at one week before and at three months after realignment surgery in ADS patients. Adult degenerative scoliosis (ADS) represents a significant healthcare burden with exceedingly high and increasing prevalence, particularly among the elderly. Radiographic alignment measures and patient-reported outcomes currently serve as the standard means to assess spinal alignment, deformity, and stability. Neurological examinations have served as qualitative measures for indicating muscle strength, motor deficits, and gait abnormalities. Three-Dimensional motion analysis is increasingly being used to identify and measure gait and balance instability. Recently, techniques have been established to quantify balance characteristics described by Dubousset as the "cone of economy" (CoE). The relationship between radiographic alignment parameters and CoE balance measures of ADS patients before and after realignment surgery is currently unknown. 29 ADS patients treated with realignment surgery. Patients were evaluated at one week before realignment surgery and at their three-month follow-up examination. During each evaluation, patients completed self-reported outcomes (visual analog scales for pain, Oswestry Disability Index, SRS22r) and a functional balance test. Mean changes in dependent measures from before to after surgery were compared using paired t-tests. Pearson correlations were used to test for significant correlations between changes in radiographic and CoE measures. Significant improvements were found for all patient-reported outcomes, in several radiographic measures, and in CoE measures. Improvements of scoliosis Cobb angle, coronal pelvic tilt, lumbar lordosis, and thoracic kyphosis showed significant correlations with CoE sway and total distance measures at both the center of mass and center of the head. Improved radiographic alignment measures significantly correlated with improved CoE balance measures among ADS patients treated with realignment surgery at their three-month follow-up. These findings indicate that functional balance evaluations when used in conjunction with radiographic measurements, may provide a more robust and improved patient-specific sensitivity for postoperative assessments. CoE balance may represent a new measure of added value for surgical intervention of ADS.

Impact of corset bracing on 3D spine kinematics during ADL in children with Spondylolysis.

Spondylolysis is a stress fracture of the vertebral pars interarticularis that frequently affects adolescents involved in sports. Conservative bracing methods may assist the clinician in treating spondylolysis, though there is a need to further validate these techniques. The goal of this study was to evaluate differences in the 3D movements of the thoracic and lumbar spine before and after bracing. Five patients (mean age 14.4 ± 1.3 years) with spondylogenic back pain were evaluated for kinematic measurements using a Vicon motion capture system. Patients performed activities both with and without a lumbar corset brace including walking, kneeling, standing from a chair, standing from the floor, ascending and descending stairs, and lifting. Patients were evaluated for differences in thoracic and lumbar range of motion (ROM) in the braced and unbraced condition. While wearing the brace, patients demonstrated reduced extension ROM of the thoracic spine while walking (mean reduction = 0.4°), ascending stairs (3.0°), descending stairs (2.1°), lifting (14.8°), standing from a chair (4.1°), standing from the floor (16.7°), and kneeling (8.4°). Patients also exhibited reduced extension ROM of the total lumbar spine while ascending stairs (mean reduction = 1.8°), lifting (12.7°), standing from a chair (9.5°), standing from the floor (11.8°), and kneeling (4.7°). These results provide evidence that bracing reduces stress on the pars interarticularis and relieves symptoms in the athlete with spondylogenic back pain, thereby facilitating a return to sports.

The effect of scoliosis support orthosis bracing on adult spinal deformity patients: evaluation of gait and dynamic balance.

Non-operative treatment is regarded as the first-line therapy for patients with adult spinal deformity (ASD) without neurologic deficits or significant impairment. While there is high-level evidence supporting the use of rigid bracing in adolescent idiopathic scoliosis, there is a paucity of literature pertaining to the use of scoliosis support orthosis (SSO) in ASD patients. To investigate the impact of an SSO on pain, gait parameters, and functional balance measures in symptomatic ASD patients. Thirty ASD patients (26 Females, Age: 72.7, Cobb Angle: 47.1°) were evaluated on 3 different occasions: first day of bracing: baseline (Pre), and 45-min post fitting (Post45m), and after 8-weeks of bracing for 4 hours a day (Post8w). Each patient performed a 6-minute walk (over-ground gait), a dynamic balance test, and completed VAS, ODI, and SRS22r. Significant short- and long-term improvements using SSO were found in the 6-minute walk (Pre: 278.6; Post45m: 322.2; Post8w: 338.8 m, p<0.001), walking speed (Pre: 0.88; Post45m: 0.97; Post8w: 0.97 m/s, p<0.001), head total sway distance during the balance test (Pre: 81.33; Post45m: 68.63; Post8w: 60.72 cm, p=0.048), low-back pain (VAS: Pre: 5.5; Post45m: 3.5; Post8w: 3.3, p<0.001), and for the ODI (Pre: 41.9; Post45m: 32.9; Post8w: 30.1, p=0.005).This study demonstrated clinically significant improvements in PROMs, spatiotemporal gait measures, and functional balance measures after continuous use of a SSO. These improvements were observed immediately following brace-fitting and maintained at an 8-week follow-up. Given these results, it is reasonable to consider a SSO for conservative management of patients with mild symptoms of pain and deformity, and who have not yet progressed to meet surgical indications.

Avian influenza virus H9N2 survival at different temperatures and pHs.

The H9N2 avian influenza virus (AIV) subtype has become endemic in Israel since its introduction in 2000. The disease has been economically damaging to the commercial poultry industry, in part because of the synergistic pathology of coinfection with other viral and/or bacterial pathogens. Avian influenza virus viability in the environment depends on the cumulative effects of chemical and physical factors, such as humidity, temperature, pH, salinity, and organic compounds, as well as differences in the virus itself. We sought to analyze the viability of AIV H9N2 strains at three temperatures (37, 20, and 4 C) and at 2 pHs (5.0 and 7.0). Our findings indicated that at 37 C AIV H9N2 isolate 1525 (subgroup IV) survived for a period of time 18 times shorter at 20 C, and 70 times shorter period at 4 C, as measured by a decrease in titer. In addition, the virus was sensitive to a lower pH (pH 5.0) with no detectable virus after 1 wk incubation at 20 C as compared to virus at pH 7.0, which was viable for at least 3 wk at that temperature. The temperature sensitivity of the virus corresponds to the occurrence of H9N2 outbreaks during the winter, and lower pH can greatly affect the viability of the virus.

An Epizootiological Report of the Re-emergence and Spread of a Lineage of Virulent Newcastle Disease Virus into Eastern Europe.

A number of contemporary outbreaks of Newcastle disease (ND) in Israel, Turkey, Georgia and Bulgaria have all been caused by a very similar viruses related to lineage 5a (genotype VIIa). Comparison with published ND virus (NDV) sequences suggests that this virus strain originated in South-East Asia and on introduction has circulated widely in backyard poultry in the Middle East and into Eastern Europe. An intracerebral pathogenicity index of 1.9 was obtained for a representative isolate from Bulgaria. In addition, the International Reference Laboratory for ND has characterized a molecular epidemiologically linked virus that has been reported to have caused disease in well-vaccinated broiler chickens in Pakistan. In the 1990s, another strain from the 5a lineage NDV was introduced into Europe and spread across the continent causing numerous outbreaks up to 1999. Despite improved controls, including good diagnostic tests and widespread vaccination, in commercial poultry, the novel circulating NDV strains described here have been established widely in the region and represent an increased risk for similar disease outbreak events to reoccur within the EU.

Newcastle disease virus in little owls (Athene noctua) and African penguins (Spheniscus demersus) in an Israeli zoo.

Newcastle disease is a contagious and often fatal disease, capable of affecting all species of birds. A velogenic Newcastle disease virus (vNDV) outbreak occurred in an Israeli zoo, in which Little owls (Athene noctua) and African penguins (Spheniscus demersus) were found positive for presence of NDV. Some of them have died. The diagnostic process included: post-mortem examination, histopathology, real-time RT-PCR assay, virus isolation, serology, intracerebral pathogenicity index and phylogenetic analysis. A vNDV was diagnosed and found to be closely related to isolates from vNDV outbreaks that occurred in commercial poultry flocks during 2011. All isolates were classified as lineage 5d.

Development of a real-time TaqMan RT-PCR assay for the detection of H9N2 avian influenza viruses.

Avian influenza viruses (AIVs) of the H9N2 subtype are a major economic problem in the poultry industry in Israel. Most field isolates from the last decade differ significantly from H9N2 isolates from Europe and the USA, rendering published detection methods inadequate. This study aimed to develop a real-time TaqMan((R)) RT-PCR assay, based on a conserved region in the HA9 gene. The assay was validated with viruses representing different genetic subtypes and other common avian pathogens, and was found specific to H9N2. The real-time RT-PCR assay was compared to RT-PCR, which is in routine diagnostic use. Real-time RT-PCR was found to be more sensitive than RT-PCR by 1.5-2.5 orders of magnitude when testing tracheal swabs directly and by 2-3 orders of magnitude allantoic fluid after AIV propagation in embryonated eggs. Sensitivity was quantified by using 10-fold dilutions of the H9-gene amplification fragment, and real-time RT-PCR was found to be 10(4)-fold more sensitive than RT-PCR. Clinical samples, which included tracheal and cloacal swabs, as well as allantoic fluid, were tested by both methods. By real-time RT-PCR 20% more positive H9N2 samples were detected than by RT-PCR. The real-time RT-PCR assay was found suitable for detection and epidemiological survey not only of Israeli H9N2 viruses, but also for isolates from other parts of the world.

Relationship between calcium release and potassium release in rat parotid gland.

1. A study was made of the role of Ca release in mediating the sustained phase of K release (86 Rb release) in the rat parotid gland due to receptor activation. 2. Sr could substitute for Ca in supporting the sustained phase of the 86Rb release due to carbachol. Sr was less effective than Ca, while Ba was ineffective. 3. Sr could also restore responsiveness of the transient phase to agonists in media lacking Ca. Again, Sr was less effective than Ca, and Ba was without effect. 4. Carbachol stimulated release of 45Ca from parotid gland slices. The amount of Ca released (about 0.2 micromole/g) was much greater than the estimated Ca influx for the same period. 5. Release of 45Ca by carbachol prevented release due to a subsequent exposure to substance P. 6. Release of 45Ca due to substance P was significantly increased if muscarinic receptors were activated during tissue labelling. 7. These results support an earlier hypothesis whereby different agonists (such as carbachol and substance P) stimulate the release of Ca from a common pool and the release of this Ca mediates the transient phase of the K release response.