The Safety and Efficacy Evaluation of PRRS Attenuated Vaccine BG895 Strain in Experimental Pigs

From the PRRSV virulent strain BG8 isolated from a PRRSV-infected pig, using serial passage method in MARC-145 cell line, we have successfully obtained an attenuated strain in 95th passage, named as BG895, with high potential to be a vaccine candidate. In this study, we present the results of the safety and efficacy evaluation of BG895 against PRRSV in experimental pigs. Trial results of vaccine formula using strain BG895 have very high safety when inoculating 5 doses/animal and 10 doses/animal. Evaluation of immune response by ELISA method showed that, from 14 days post inoculation, anti-PRRSV antibodies were detected in the serum of all inoculated pigs in vaccine batches with the lowest S/P index of 1.50 ± 0.4 and the highest S/P was 2.36 ± 0.1 from 28 days post inoculation. The IPMA method showed that the antibody titer of the vaccine reached ≥ 1/160 in 100% of pigs from 21 days post inoculation andreached ≥ 1/640 in 100% of pigs from 28 days post inoculation, indicating that the vaccine was effective at protecting 100% of pigs from 28 days post inoculation. The protective effect of the vaccine was evaluated by the virulent challenge from 28 days post inoculation with 1 dose/animal compared with the control group. The results showed that compared with all pigs in the control group with typical clinical manifestations of Blue-ear disease, all inoculated pigs had normal body temperature and weight gain, besides, the S/P index increased from 1.65 ± 0.1 to the highest 2.99 ± 0.2; the average antibody titer was >1/2560, and virus wasnot detected in nasal fluid by real-time RT-PCR from 7 days post challenge. These experimental results confirmed the safety and efficacy of the attenuated PRRS vaccine based on BG895strain.

Energy-dependent Boundaries of Earth's Radiation Belt Electron Slot Region

The variations in radiation belt boundaries reflect competition between acceleration and loss physical processes of energetic electrons, which is an important issue for radiation belts of planets with an internal magnetic field (e.g., Earth, Jupiter, and Saturn). Based on high-quality measurements from Van Allen Probes spanning the years 2014–2018, we develop an empirical model of the energy-dependent boundaries of Earth's electron radiation belt slot region, showing that the lower boundary follows a logarithmic function of the electron energy while the upper boundary is controlled by two competing energy-dependent processes, namely compression and recovery. The compression process relates linearly to a 15 hr averaged Kp index, while the recovery process is found to be approximately proportional to time. Detailed data-model comparisons demonstrate that our model, using only the Kp index and time epoch as inputs, reconstructs the slot region boundaries in real time for 200 keV to 2 MeV electrons under varying geomagnetic conditions. Such a data-driven empirical model is prerequisite to understanding the dynamic changes of the slot region in response to both solar and geomagnetic activities. The model can be readily incorporated into future global simulations of radiation belt electron dynamics in Earth's inner magnetosphere and provide new insights into the study of Saturn's and Jupiter's radiation belt variability.

Rối loạn canxi, phospho ở bệnh nhân bệnh thận mạn giai đoạn cuối điều trị bảo tồn

TÓM TẮT Mục tiêu: Khảo sát nồng độ canxi, phospho và hocmon tuyến cận giáp ở bệnh nhân bệnh thận mạn giai đoạn cuối điều trị bảo tồn. Phương pháp: Nghiên cứu mô tả cắt ngang được thực hiện trên 50 bệnh nhân bệnh thận mạn giai đoạn cuối điều trị bảo tồn tại Bệnh viện hữu nghị đa khoa Nghệ An. Nồng độ canxi, phospho và PTH máu được xét nghiệm định lượng và so sánh với khoảng giới hạn bình thường của mỗi loại xét nghiệm. Kết quả: Nồng độ canxi máu trung bình là 1,94 ± 0,05 mmol/l, trong đó có 78,00% số bệnh nhân có tình trạng giảm canxi máu. Nồng độ phospho máu trung bình là 1,84 ± 0,58 mmol/l, trong đó 52,00% số bệnh nhân có tăng phospho máu. Chỉ số Ca x P máu trung bình là 3,52 ± 1,13 mmol2/l2, trong đó có 22,00% có tăng chỉ số Ca x P máu. Nồng độ PTH máu trung bình là 280,87 ± 222,35 pg/ml, trong đó tỷ lệ bệnh nhân có tăng nồng độ PTH máu là 36,00%. Nhận thấy nồng độphospho, chỉ số Ca x P và nồng độ PTH máu tương quan nghịch với tuổi và mức lọc cầu thận. Kết luận: Nghiên cứu cho thấy ở bệnh nhân bệnh thận mạn giai đoạn cuối điều trị bảo tồn có một tỷ lệ cao bệnh nhân có giảm nồng độ canxi máu, tăng nồng độ phospho máu và PTH máu. ABSTRACT DISORDERS OF BLOOD CALCIUM, PHOSPHO IN PATIENTS WITH END - STAGE RENAL DISEASE RECEIVING CONSERVATIVE THERAPY Objective: To investigate the concentration of blood calcium, phosphorus and parathyroid hormone in patients with ESRD who were treated by conservative therapy. Methods: A cross - sectional descriptive study was performed on 50 patients with ESRD who were treated by conservative therapy at Nghe An Friendship General Hospital. Blood calcium, phosphorus and parathyroid hormone levels were calculated and compared with the normal ranges, respectively. Results: The average blood calcium concentration was 1.94 ± 0.05 mmol/l, of which 78.00% of the patients had hypocalcemia. The average blood phosphorus concentration was 1.84 ± 0.58 mmol/l, of which 52.00% of the patients had hyperphosphatemia. The average blood Ca x P index was 3.52 ± 1.13 mmol2/l2, of which 22.00% had high blood Ca x P index. The average blood PTH concentration was 280.87 ± 222.35 pg/ml, in which the proportion of patients with increased blood PTH concentration was 36.00%. It was found that blood phosphorus concentration, Ca x P index and blood PTH concentration were inversely correlated with age and glomerular filtration rate. Conclusion: The study shows that in patients with ESRD who were treated by conservative therapy has a high percentage of patients with low concentration of blood calcium, high concentration ofblood phosphorus and high concentration of blood PTH.

The Performance Index Identifies Changes Across the Dual Task Timed Up and Go Test Phases and Impacts Task-Cost Estimation in the Oldest-Old

Introduction: Dual tasking is common in activities of daily living (ADLs) and the ability to perform them usually declines with age. While cognitive aspects influence dual task (DT) performance, most DT-cost (DT-C) related metrics include only time- or speed- delta without weighting the accuracy of cognitive replies involved in the task.Objectives: The primary study goal was to weight the accuracy of cognitive replies as a contributing factor when estimating DT-C using a new index of DT-C that considers the accuracy of cognitive replies (P-index) in the instrumented timed up and go test (iTUG). Secondarily, to correlate the novel P-index with domains of the Mini-Mental State Examination (MMSE).Methods: Sixty-three participants (≥85 years old) took part in this study. The single task (ST) and DT iTUG tests were performed in a semi-random order. Both the time taken to complete the task measured utilizing an inertial measurement unit (IMU), and the accuracy of the cognitive replies were used to create the novel P-index. Clinical and sociodemographic data were collected.Results: The accuracy of the cognitive replies changed across the iTUG phases, particularly between the walk 1 and walk 2 phases. Moreover, weighting 0.6 for delta-time (W1) and 0.4 for cognitive replies (W2) into the P-index enhanced the prediction of the MMSE score. The novel P-index was able to explain 37% of the scores obtained by the fallers in the “spatial orientation” and “attention” domains of the MMSE. The ability of the P-index to predict MMSE scores was not significantly influenced by age, schooling, and number of medicines in use. The Bland-Altman analysis indicated a substantial difference between the time-delta-based DT-C and P-index methods, which was within the limits of agreement.Conclusions: The P-index incorporates the accuracy of cognitive replies when calculating the DT-C and better reflects the variance of the MMSE in comparison with the traditional time- or speed-delta approaches, thus providing an improved method to estimate the DT-C.