High-Intensity Physical Activity with High Serum Vitamin D Levels is Associated with a Low Prevalence of Osteopenia and Osteoporosis: A Population-Based Study.

We found that combination of high-intensity PA and high 25(OH)D levels was associated with low prevalence of osteoporosis/osteopenia. In addition, the prevalence of osteoporosis was lower in the low PA with high 25(OH)D levels than in the moderate or high PA with low 25(OH)D levels. INTRODUCTION: The aim of this study was to explore the association of physical activity (PA) and serum 25-hydroxyvitamin D (25[OH]D) levels with osteopenia/osteoporosis. METHODS: The Korean National Health and Nutrition Examination Survey data from 2008 to 2011 were used in this study. Data from 6868 individuals were selected. Each individual's level of PA was classified as 'low', 'moderate', or 'high'. Serum 25(OH)D levels were classified as 'low' or 'high'. Accordingly, the combined PA and 25(OH)D groups were divided into 6 groups. Bone mineral density (BMD) was classified as 'normal (T score ≥ - 1.0)', 'osteopenia (- 2.5 < T score < - 1.0)' or 'osteoporosis (T score ≤ - 2.5)'. Crude and adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were calculated using multinomial logistic regression models. RESULTS: The AORs (95% CIs) for osteopenia were 0.64 (0.50-0.83) in the high PA with high 25(OH)D group and 0.69 (0.53-0.88) in the moderate PA with high 25(OH)D group. The AORs (95% CIs) for osteoporosis were increased in the groups in ascending order as follows: high PA with high 25(OH)D (0.40 [0.28-0.57]) < moderate PA with high 25(OH)D (0.47 [0.33-0.66]) < low PA with high 25(OH)D (0.59 [0.42-0.83]) < high PA with low 25(OH)D (0.70 [0.49-1.00]) < moderate PA with low 25(OH)D (0.76 [0.53-1.07]) < low PA with low 25(OH)D. This result was consistent in males but not evident in females. CONCLUSION: We suggest that the combination of high-intensity PA and high 25(OH)D levels is positively associated with high BMD.

Interleukin-18 as an efficient marker for remission and follow-up in patients with inactive adult-onset Still's disease.

OBJECTIVES: Diagnosis of adult-onset Still's disease (AOSD) is difficult because of a lack of pathognomonic findings and markers. The aim of this study was to investigate the efficacy of interleukin (IL)-18 and free IL-18 in the diagnosis and follow-up of patients with AOSD. METHOD: Levels of inflammatory cytokines, IL-18, IL-18 binding protein (IL-18BP), and free IL-18 were compared in 80 AOSD patients and 90 controls. The AOSD patients were divided into active and inactive groups according to disease activity, and the inactive patients were subdivided into a remission subgroup and a low disease activity subgroup. We compared erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), ferritin, IL-18, and free IL-18 as disease activity markers in the AOSD patients. Serial serum levels of activity markers were measured in 52 of the 80 AOSD patients at 3- to 6-month intervals. RESULTS: There were significantly higher levels of IL-18 and free IL-18 in the AOSD patients than in the controls. IL-18 and free IL-18 were significantly higher in the active group than the inactive group (p < 0.001 for all). Unlike other activity markers, IL-18 and free IL-18 levels in the low disease activity subgroup were significantly higher than those in the remission subgroup within the inactive group (p = 0.004 and 0.005, respectively). During serial follow-up, ferritin and IL-18 showed a significant decrease in the responder and remission subgroup. CONCLUSIONS: IL-18 might be an efficient marker for diagnosis and follow-up of AOSD and might also be a useful predictor of remission, especially in clinically inactive patients.

A prospective randomised comparison of two insertion methods for i-gel placement in anaesthetised paralysed patients: standard vs. rotational technique.

In this prospective randomised study, we compared two techniques for i-gel(™) insertion. One hundred and eighty-one anaesthetised, paralysed adult patients were randomly allocated into one of two groups. In the standard group (n = 91), the i-gel was inserted using the standard technique. In the rotation group (n = 90), the i-gel was rotated 90° anticlockwise in the mouth and re-rotated in the hypopharynx to the original alignment. The success rate, insertion time, air leak pressure and complications were assessed. The success rate for insertion at the first attempt was lower for the standard technique, 78 (86%) vs. 87 (97%; p = 0.016). The mean (SD) insertion time was longer (26.9 (14.5) s vs. 22.4 (10.2) s; p = 0.016) and air leak pressure was lower (22.5 (10.4) cm H2O vs. 27.1 (9.4) cm H2O; p = 0.002) in the standard group. The incidence of bloodstaining was higher with the standard technique (8 (9%) vs. 1 (1%); p = 0.034). This study suggests that the rotational technique is superior to the standard technique for i-gel insertion.

Effect of tamsulosin on stone expulsion in proximal ureteral calculi: an open-label randomized controlled trial.

AIM: Medical expulsive therapy (MET) using alpha-blockers is effective for distal ureteral calculi (UC). We aimed to evaluate the efficacy of tamsulosin for proximal UC expulsion. MATERIALS AND METHODS: An open-label randomized controlled trial was conducted with 108 patients who agreed to conservative management for single, radiopaque, proximal UC ≤ 6 mm and were randomized into group A (n = 54, conservative managements only) or B (n = 54, 0.2 mg tamsulosin once a day). The primary end-point was stone passage rates (SPR) in the intention-to-treat population in 4 treatment weeks. The secondary end-points were estimated in per-protocol population and were time to stone passage, post-trial Euro-quality-of-life (EuroQOL) score, oral analgesic requirements, and willingness to undergo conservative treatment again. RESULTS: The two groups were well balanced in terms of baseline patient and stone characteristics. Seventy nine patients (73.2%; 35 of group A and 44 of group B) completed the study protocol. The overall SPR was 60.2% (65/108). Group B had a higher SPR (74.1%; 40/54) than group A (46.3%; 25/54; p = 0.003) and a significantly shorter time to stone passage (mean days, A: 19.6 vs. B: 14.3, p = 0.005). The groups did not differ in post-trial EuroQOL score or oral analgesic requirements, whereas 74.3% (26/35) of group A and 90.9% (40/44) of group B were willing to undergo conservative treatment again (p = 0.048). Univariate logistic regression analysis showed that stone size (OR = 1.447, p = 0.045) and tamsulosin treatment (OR = 3.314, p = 0.004) significantly predicted stone expulsion. On multivariate analysis, only tamsulosin was statistically significant (OR=3.198, p = 0.021). CONCLUSIONS: Tamsulosin was associated with significantly higher stone expulsion rate and shorter expulsion time in proximal UC ≤ 6 mm compared with conservative managements only. Our results indicate that similar to patients with distal UC, MET using tamsulosin is a reasonable treatment option for patients with proximal UC.

Characteristics of primary cutaneous lymphoma according to WHO-EORTC classification in Korea.

BACKGROUND: Primary cutaneous lymphoma (PCL) is an extranodal non-Hodgkin lymphoma with primary involvement of the skin. Epidemiological data on PCLs according to the World Health Organization/European Organization for Research and Treatment of Cancer classification (WHO-EORTC) has not been investigated in Korea to date. AIM: To evaluate the demographic characteristics, clinical and histological features, and survival data of patients with PCL according to the WHO-EORTC classification. METHODS: In total, 93 patients with PCL were retrospectively identified from an extensive review of medical records over a 16-year period. RESULTS: The tumours found included primary cutaneous CD30+ lymphoproliferative disorders, extranodal natural killer/T-cell lymphoma and primary cutaneous diffuse large B-cell lymphoma. We found that 81.6% of the patients had primary cutaneous T-cell and natural killer-cell lymphoma, and 16.2% had primary cutaneous B-cell lymphoma, with 2.2% having precursor haematological neoplasms. The median age was 52 years (range 3-95) and the male : female ratio was 1: 1.16. The 5-year survival rate was 92.5%. CONCLUSIONS: The incidence rates of many PCL subtypes in Koreans differ from those of other countries.

Arterial Spin-Labeling MR Imaging for the Differential Diagnosis of Venous-Predominant AVMs and Developmental Venous Anomalies.

BACKGROUND AND PURPOSE: Venous-predominant AVMs are almost identical in appearance to developmental venous anomalies on conventional MR imaging. Herein, we compared and analyzed arterial spin-labeling findings in patients with developmental venous anomalies or venous-predominant AVMs, using DSA as the criterion standard. MATERIALS AND METHODS: We retrospectively collected patients with either DVAs or venous-predominant AVMs, each available on both DSA and arterial spin-labeling images. Arterial spin-labeling imaging was visually assessed for the presence of hyperintense signal. CBF measured at the most representative section was normalized to the contralateral gray matter. The temporal phase of developmental venous anomalies or venous-predominant AVMs was measured on DSA as a delay between the first appearance of the intracranial artery and the lesion. Correlation between the normalized CBF and the temporal phase was evaluated. RESULTS: Analysis of 15 lesions (13 patients) resulted in categorization into 3 groups: typical venous-predominant AVMs (temporal phase, <2 seconds), intermediate group (temporal phase between 2.5 and 5 seconds), and classic developmental venous anomalies (temporal phase, >10 seconds). Arterial spin-labeling signal was markedly increased in the typical venous-predominant AVM group, while there was no discernible signal in the classic developmental venous anomaly group. In the intermediate group, however, 3 of 6 lesions showed mildly increased arterial spin-labeling signal. The normalized CBF on arterial spin-labeling and the temporal phase on DSA were moderately negatively correlated: r(13) = 0.66, P = .008. CONCLUSIONS: Arterial spin-labeling may predict the presence and amount of arteriovenous shunting in venous-predominant AVMs, and using arterial spin-labeling enables confirmation of typical venous-predominant AVMs without DSA. However, lesions with an intermediate amount of shunting suggest a spectrum of vascular malformations ranging from purely vein-draining developmental venous anomalies to venous-predominant AVMs with overt arteriovenous shunting.

Low-power-Consumption metal oxide NO2 gas sensor based on micro-heater and screen printing technology.

An NO2 micro gas sensor was fabricated based on a micro-heater using tin oxide nano-powders for effective gas detection and monitoring system with low power consumption and high sensitivity. The processes of the fabrication were acceptable to the conventional CMOS processes for mass-production. Semiconducting SnO2 nano-powders were synthesized via the co-precipitation method; and to increase the sensitivity of the NO2 gas rare metal dopants were added. In the structure of the micro-heater, the resistances of two semi-circular Pt heaters were connected to the spreader for thermal uniformity. The resistance of each heater becomes an electrically equal Wheatstone-bridge, which was divided in half by the heat spreading structure. Based on the aforementioned design, a low-power-consumption micro-heater was fabricated using the CMOS-compatible MEMS processes. A bridge-type micro-heater based on the Si substrate was fabricated via surface micro-machining. The NO2 sensing properties of a screen-printed tin oxide thick film device were measured The micro gas sensors showed substantial sensitivity down to 0.5 ppm NO2 at a low power consumption (34.2 mW).

Prescription pattern of oxybutynin ER in patients with overactive bladder in real life practice: a multicentre, open-label, prospective observational study.

AIMS OF STUDY: To investigate the prescription pattern and dose distribution of the antimuscarinic agent oxybutynin extended release (ER) in patients with overactive bladder (OAB) in actual clinical practice. MATERIALS AND METHODS: In this multicentre, prospective, observational, flexible-dosing study, the dosage of oxybutynin ER for each patient was adjusted after discussions of efficacy and tolerability between doctor and patient, over a 12 week treatment period. Efficacy was measured by administering the Primary OAB Symptom Questionnaire (POSQ) before and after treatment. Patients were also administered, the patient perception of treatment benefit (PPTB) questionnaire at the end of the study. Adverse events (AE) were documented at each study visit. RESULTS: Of the 809 patients enrolled, 590 (73.2%) continued to take study medication for 12 weeks. Most patients were prescribed 5 (24.2%) or 10 (68.8%) mg/day oxybutynin ER at the start of treatment. Most were also prescribed 5 (19.1%) or 10 (67.4%) mg/day at the end of treatment, with a dose escalation rate of 14.9%. All OAB symptoms evaluated by the POSQ were improved; 94.1% of patients reported benefits from treatment and 89.3% were satisfied. Independent predictive factors for discontinuation were female, younger age (age ≤ 65), obesity (BMI ≥ 25), severe symptoms (USS, Gr. 5) and larger numbers of other co-medications. CONCLUSIONS: Most patients were prescribed 5-10 mg/day oxybutynin ER as both starting and maintenance doses, with a dose escalation rate of only 14.9%. Prescription of > 10 mg/day oxybutynin ER was not frequent in real life practice.

[Development of a nested polymerase chain reaction test for the diagnosis of transmissible gastroenteritis of pigs]. / Desarrollo de una prueba de reacción en cadena de la polimerasa anidada para el diagnóstico de la gastroenteritis transmisible del cerdo.

The aim of this study was to develop a nested polymerase chain reaction (nested PCR) for the rapid detection of transmissible gastroenteritis virus (TGEV) of pigs. The primers were designed on the basis of highly conserved regions of several TGEV sequences included in the analysis. External primers were used to amplify a fragment of the expected size (441 bp) in all the samples evaluated using reverse transcriptase polymerase chain reaction (RT-PCR), but with very low intensity. In the second amplification (nested PCR), internal primers were used to amplify a fragment of the expected size (168 bp), with good concentration. The performance of the test based on virus isolates in tissue culture and in clinical samples was judged good for the virological diagnosis of transmissible gastroenteritis of pigs.

Stimulation of dendritic cells with Helicobacter pylori vacuolating cytotoxin negatively regulates their maturation via the restoration of E2F1.

Helicobacter pylori induces an infiltration of dendritic cells (DCs) into the infected gastric mucosa. Although DCs play an important role in the regulation of inflammation, the effects of H. pylori vacuolating cytotoxin (VacA) on DC maturation process have not yet been elucidated. The role of VacA in DC maturation following co-exposure to Escherichia coli lipopolysaccharide (LPS) was investigated. The treatment of immature DCs with LPS up-regulated the expression of surface molecules [e.g. CD40, CD80, CD86 and major histocompatibility complex (MHC) class II], as well as the production of cytokines [e.g. interleukin (IL)-1ß, IL-12p70 and tumour necrosis gactor (TNF)-α] compared with those of unstimulated controls. Co-stimulation with H. pylori VacA significantly reduced the up-regulated DC maturation markers induced by LPS. In addition, VacA sustained the immature state of DCs with high endocytosis and low migratory capacity. The LPS-induced down-regulation of E2F1 expression in DCs was recovered by co-stimulation with VacA. Moreover, suppression of E2F1 by small interfering RNA resulted in a significant recovery of the inhibited DC maturation by VacA. In contrast, VacA did not affect nuclear factor (NF)-κB responses to LPS and the NF-κB signal was not associated with VacA-induced inhibition of DC maturation. These results suggest that the exposure of DCs to H. pylori VacA negatively regulates DC maturation via the restoration of E2F1. The immunomodulatory action of VacA on DCs may contribute to the ability of VacA-producing H. pylori to establish a persistent infection in the gastric mucosa.

A mechanism for the action of the compound DA-6034 on NF-κB pathway activation in Helicobacter pylori-infected gastric epithelial cells.

DA-6034 is a synthetic derivative of eupatilin, a flavonoid with anti-inflammatory effects. The aim of this study was to investigate the effects of DA-6034 on the interactions between IκB kinase (IKK) and heat shock protein 90 (Hsp90), and activation of the nuclear factor-kappaB (NF-κB) signalling pathway in human gastric epithelial cells infected with Helicobacter pylori. MKN-45 gastric epithelial cell line was treated with DA-6034 and H. pylori. DA-6034 significantly inhibited NF-κB activation and upregulated the expressions of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 in MKN-45 cells infected with H. pylori. However, DA-6034 did not influence activator protein-1 DNA binding activity in H. pylori-infected gastric epithelial cells. Pretreatment with DA-6034 attenuated the H. pylori-induced increase in IKK activity, and Hsp90 was associated with IKK-α and IKK-γ in MKN-45 cells. Treatment with DA-6034 dissociated the Hsp90 and IKK-γ complex in H. pylori-infected cells, leading to the inhibition of IL-8 expression. These results suggest that the eupatilin derivative 7-carboxymethyloxy-3',4',5-trimethoxy flavone has anti-inflammatory activity in gastric epithelial cells infected with H. pylori through the promotion of the dissociation of the IKK-γ-Hsp90 complex and suppression of NF-κB signalling.

Reduced pre-pregnancy proteinuria is associated with improving postnatal maternal renal outcomes in IgA nephropathy women.

AIMS: In patients with immunoglobulin A (IgA) nephropathy, postnatal renal outcomes vary depending on kidney function and proteinuria. However, whether a decrease in proteinuria prior to conception improves postnatal maternal renal outcomes is unknown. METHODS: This was a single-center retrospective study. A total of 52 pregnant women with biopsy-proven IgA nephropathy were enrolled in the study between January 2004 and December 2009. We collected data on proteinuria, which had been measured 1 year prior to conception, at conception, during pregnancy, and postnatally. The study outcomes included changes in estimated glomerular filtration rate (eGFR) and proteinuria. RESULTS: The median serum creatinine, eGFR, and proteinuria levels at conception were 0.8 (0.5 - 2.6) mg/dl, 91.2 (24.1 - 157.0) ml/min, 0.7 (0.0 - 3.5) g/g, respectively. Compared with values measured at conception, serum creatinine (0.8 - 1.0 mg/dl, p < 0.01) and proteinuria (0.7 - 1.5 g/g, p < 0.01) increased significantly postnatally, while eGFR decreased (91.2 - 77.8 ml/min, p < 0.01). In a multiple linear regression analysis, proteinuria at conception were independently associated with a faster decline in postnatal maternal eGFR (ß = 4.50, p < 0.05). In addition, a less decline in maternal eGFR was observed in patients with a reduction in proteinuria (> 30%) prior to pregnancy, compared with those with a less reduction (≤ 30%). As for newborn outcomes, preterm delivery, caesarean section, low birth weight < 2,500 g, and need for neonatal intensive care were 15.4%, 46.2%, 25.0% and 7.7%, respectively. CONCLUSIONS: This study showed that in women with IgA nephropathy, proteinuria was significantly associated with the deterioration of postnatal maternal renal outcomes. Our study also suggests that a strategy for reducing proteinuria prior to pregnancy is required to preserve kidney function after delivery.

CD40 ligation induces Apo-1/Fas expression on human B lymphocytes and facilitates apoptosis through the Apo-1/Fas pathway.

The Apo-1/Fas antigen (CD95) mediates programmed cell death of lymphocytes when bound by Fas ligand or anti-Apo-1/Fas antibody. In contrast, the CD40 antigen provides a potent activation and survival signal to B lymphocytes when it is engaged by its T cell ligand (CD40L, gp39) or cross-linked by anti-CD40 antibody. In this study, we use human tonsillar B cells and the Ramos Burkitt's lymphoma B cell line, which serves as a model for human germinal center B lymphocytes, to study the effectors of Apo-1/Fas expression and apoptosis of human B cells. We found that Apo-1/Fas expression was upregulated on both malignant and normal human B lymphocytes after CD40 ligation induced by (a) cognate T helper-B cell interaction mediated by microbial superantigen (SAg); (b) contact-dependent interaction with CD40L+, but not CD40L- Jurkat mutant T cell clones; and (c) monoclonal anti-CD40, but not any of a panel of control antibodies. Enhanced B cell Fas/Apo-1 expression is functionally significant. Coculture of Ramos Burkitt's lymphoma line cells with irradiated SAg-reactive CD4+ T cells with SAg or CD40L+ Jurkat T cells results in B cell apoptosis, evidenced by reduced cell viability and DNA laddering. This process is augmented by the addition of anti-Apo-1/Fas monoclonal antibody, consistent with an acquired susceptibility to Apo-1/Fas-mediated apoptosis. These data support an immunoregulatory pathway in which seemingly contradictory signals involving the B cell proliferation/survival antigen CD40, as well as the Apo-1/Fas molecule, which mediates programmed cell death of lymphocytes, are linked in the process of human B cell activation.

Anticytokine therapy in systemic lupus erythematosus.

Systemic lupus erythematosus is a prototype of heterogeneous autoimmune disease. There have been few newly approved therapeutic agents in lupus treatment for many reasons. Several animal studies and human data have shown that many potential cytokines are related to the pathogenesis and disease activity of systemic lupus erythematosus. Cytokines are produced by many immune cell types and have variable functions in the immune system. Following the success of biological agents in the treatment of inflammatory arthritis, inflammatory bowel disease, and psoriasis, biological targeting to specific cytokines or receptor molecules is now promising in the treatment of systemic lupus erythematosus. In addition to B-cell deleting modalities, clinical trials targeting potential cytokines associated with disease pathogenesis are underway at various clinical stages. Among potential cytokines, targeting agents against B-cell activating factor and interferon-alpha are in the most advanced stage, and belimumab (anti-B-cell activating factor antibody) could be the first biological agent approved in the treatment of systemic lupus erythematosus. Anti-tumor necrosis factor was tried with some success, but with a potential risk of infection in a small number of patients. In this review, we discuss the rationale for anticytokine therapies and review agents currently in clinical trials, and those that could be developed in the near future for systemic lupus erythematosus. We present the results mostly from published trials and data from http://clinicaltrials.gov/ct2/

Effects of gonadotropins on in vitro maturation and of electrical stimulation on parthenogenesis of canine oocytes.

The objective of this study was to determine the effects of gonadotropins on in vitro maturation (IVM) and electrical stimulation on the parthenogenesis of canine oocytes. In experiment I, cumulus oocyte complexes were collected from ovaries at a random phase of the oestrus cycle and cultured on maturation medium treated with hCG or eCG for 48 or 72 h. There were no significant differences in the effects on the metaphase II (MII) rate between the hCG and eCG treatment groups over 48 h (5.4% vs 5.5%). The MII rate in the co-treatment group of hCG and eCG for 48 h was higher than in each hormone treated group (15.5%, p < 0.05). In experiment 2, the parthenogenetic effect on oocyte development, at various electrical field strengths (1.0, 1.5, 2.0 kV/cm DC) for 60 or 80 mus with a single DC pulse after IVM on the co-treatment of hCG and eCG, was examined. The rate of pronuclear formation (37.1%) in electrical activation at 1.5 kV/60 mus without cytochalasin B (CB) was higher than that of oocytes activated in the other groups (p < 0.05). However, we did not observe the cleavage stages. Also, CB did not influence parthenogenesis of canine oocytes. The results showed that the pronucleus formation rate, indicative of the parthenogenesis start point, could be increased by electrical stimulation. Therefore, these results can provide important data for the parthenogenesis of canine oocytes and suggest the probability of parthenogenesis in canines.

Suspected Metallic Embolization Distal to Coiled Intracranial Aneurysms Detectable by Susceptibility-Weighted MR Imaging.

BACKGROUND AND PURPOSE: After endovascular coiling of intracranial aneurysms, round dark parenchymal lesions believed to be particulate metal are sometimes encountered in MR imaging studies of the brain. We used SWI to assess the frequency of such occurrences, in addition to exploring likely causes and clinical implications. MATERIALS AND METHODS: We reviewed 700 MR imaging studies performed between September 2018 and March 2019 at our institution as follow-up monitoring of coiled intracranial aneurysms. Any sizeable (>5 mm) rounded dark-signal lesions encountered were presumed to be metallic. The magnitudes and locations of such lesions were recorded. In patients with these lesions, pertinent procedural documentation was screened for devices used, including coils, microcatheters, microguidewires, and stents. Medical records were also examined to determine whether any related symptoms ensued. RESULTS: Twenty patients (2.8%) exhibited a total of 25 lesions on SWI. Diameters ranged from 5 to 11 mm (median, 8 mm). All except 2 lesions were located in brain regions downstream from aneurysms, but all lesions occupied vascular territories of vessels used to place guiding catheters. Other than the Synchro 14, which was routinely deployed, no device was regularly used in patients with SWI-detectable lesions; and none of the affected patients developed focal neurologic symptoms as a consequence. CONCLUSIONS: Although the origins remain unclear, distal embolization of particulate metal distal to coiled cerebral aneurysms is occasionally observed on follow-up MR imaging studies. Such lesions, however, seem to have no apparent clinical impact.

Infection with a pathogenic turkey coronavirus isolate negatively affects growth performance and intestinal morphology of young turkey poults in Canada.

Turkey coronavirus (TCoV) is an important viral pathogen causing diarrhoea of young turkey poults that is associated with sizeable economic losses for the turkey industry. Using a field isolate that was found to be free from turkey astrovirus and avian reovirus we were able to reproduce the clinical disease associated with TCoV. Clinical signs and weight gain of poults during experimental infections were compared with age-matched, uninfected controls. Poults infected at 2 days of age had 100% morbidity and 10% mortality, and birds infected at 28 days of age showed 75% morbidity and no mortality. Diarrhoea was consistently seen in infected poults at 2 to 3 days post infection (d.p.i.) with a duration of about 3 to 5 days. Mean body weights of birds infected at 2 or 28 days of age were significantly reduced compared with uninfected birds by 7 d.p.i. and remained significantly lower for the duration of the study. At 44 days of age, poults infected at 2 or 28 days of age weighed only 68.1% or 77.7%, respectively, compared with uninfected turkeys of the same age on the same diet, a mean difference in body weights of 683 or 477g, respectively. Infected birds had profound villus atrophy with some compensatory crypt hyperplasia at 5 to 7 d.p.i. Villus heights in the duodenum were significantly reduced at 7 d.p.i. We were able to reproduce enteric disease using only a pathogenic field isolate (MG10) of TCoV that negatively affected growth performance and intestinal morphology of young turkey poults.

Virus shedding and serum antibody responses during experimental turkey coronavirus infections in young turkey poults.

The course of turkey coronavirus (TCoV) infection in young turkey poults was examined using a field isolate (TCoV-MG10) from a diarrhoeal disease outbreak on a commercial turkey farm in Ontario, Canada. Two-day-old and 28-day-old poults were inoculated orally with TCoV-MG10 to examine the effect of age on viral shedding and serum antibody responses to the virus. The presence of coronavirus particles measuring 105.8+/-21.8 nm in the cloacal contents was confirmed using transmission electron microscopy. The pattern of cloacal TCoV shedding was examined by reverse-transcription polymerase chain reaction amplification of the nucleocapsid gene fragment. TCoV serum antibody responses were assessed with two recently developed TCoV enzyme-linked immunosorbent assays that used TCoV nucleocapsid and S1 polypeptides as coating antigens. Poults were found equally susceptible to TCoV infection at 2 days of age and at 4 weeks of age, and turkeys of either age shed virus in their faeces starting as early as 1 day post-inoculation and up to 17 days post-inoculation. Poults infected at 2 days of age were immunologically protected against subsequent challenge at 20 days post-inoculation. The protection was associated with measurable serum antibody responses to both the nucleocapsid and S1 structural proteins of TCoV that were detectable as early as 1 week post-infection.