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《Vaccine》2021,39(14):1933-1942
The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants.  相似文献   
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双环[1.1.1]戊烷(BCP)是一种具有三维立体结构的桥环骨架,其作为苯环、叔丁基和炔烃的生物电子等排体,已经在药物化学领域得到广泛的应用。随着BCP应用范围的扩大,BCP及其衍生物的合成日益成为研究的热点。本文对BCP衍生物的主要合成策略和方法进行总结,旨在为新药研发人员提供参考。  相似文献   
4.
《Brain stimulation》2019,12(6):1526-1536
BackgroundEvidence suggests that repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, alters resting brain activity. Despite anecdotal evidence that rTMS effects wear off, there are no reports of longitudinal studies, even in humans, mapping the therapeutic duration of rTMS effects.ObjectiveHere, we investigated the longitudinal effects of repeated low-intensity rTMS (LI-rTMS) on healthy rodent resting-state networks (RSNs) using resting-state functional MRI (rs-fMRI) and on sensorimotor cortical neurometabolite levels using proton magnetic resonance spectroscopy (MRS).MethodsSprague-Dawley rats received 10 min LI-rTMS daily for 15 days (10 Hz or 1 Hz stimulation, n = 9 per group). MRI data were acquired at baseline, after seven days and after 14 days of daily stimulation and at two more timepoints up to three weeks post-cessation of daily stimulation.Results10 Hz stimulation increased RSN connectivity and GABA, glutamine, and glutamate levels. 1 Hz stimulation had opposite but subtler effects, resulting in decreased RSN connectivity and glutamine levels. The induced changes decreased to baseline levels within seven days following stimulation cessation in the 10 Hz group but were sustained for at least 14 days in the 1 Hz group.ConclusionOverall, our study provides evidence of long-term frequency-specific effects of LI-rTMS. Additionally, the transient connectivity changes following 10 Hz stimulation suggest that current treatment protocols involving this frequency may require ongoing “top-up” stimulation sessions to maintain therapeutic effects.  相似文献   
5.
1. The non-clinical pharmacokinetic profiles of rovatirelin, a novel thyrotropin-releasing hormone (TRH) analogue, were investigated in vivo and in vitro.

2. Rovatirelin orally administered to rats and dogs was rapidly absorbed and bioavailability was estimated to be 7.3 and 41.3%, respectively. The extent of plasma protein binding of rovatirelin in rats, dogs, and humans was low in all species (~15%). The permeability of rovatirelin from blood to brain (permeability-surface area) ranged from 1.04?±?0.14 to 1.29?±?0.28?μL/min/g in rats, and rovatirelin was stable in rat plasma and brain homogenates.

3. The metabolite pattern was qualitatively similar in vitro and in vivo. In animals, rovatirelin aminopentanoic acid (rovatirelin-acid), rovatirelin aminopentanone (rovatirelin-ketone), rovatirelin pyrrolidine (4S)-hydroxy (rovatirelin-OH), (thiazoylalanyl)methylpyrrolidine (TAMP), 3-(4-thiazoyl)-l-alanine (TA), and unknown metabolites were observed. In human hepatocytes, TAMP was mainly formed and no unique human metabolite was observed.

4. The radioactivity from administered [14C]rovatirelin was predominantly excreted in faeces in rats and dogs, and almost all radioactivity was recovered 168?h after administration. Absorption, brain penetration, and stability of rovatirelin in the brain were greater than for taltirelin.

5. Thus, orally administered rovatirelin is a potentially improved treatment for spinocerebellar degeneration compared with taltirelin.  相似文献   

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Introduction

Induction chemotherapy with cytarabine and an anthracycline (7+3) remains the standard of care for acute myeloid leukemia (AML).

Patients and Methods

We retrospectively analyzed 183 newly diagnosed AML patients to compare the utility of rapid peripheral blast clearance (PBC), day of peripheral blast disappearance, residual blasts, and cellularity at day 14 bone marrow biopsy (D14BM) in predicting clinical response to 7+3 induction, overall survival (OS), and relapse-free survival (RFS).

Results

In multivariable logistic regression analysis, day 2 PBC > 85% [P = .0016] was the only predictor of remission status, with sensitivity and specificity of 75%. Peripheral blast disappearance within 5 days after induction and < 10% cellularity in D14BM predicted superior OS and RFS in multivariate analysis. Median follow-up of patients was 28 months since diagnosis. Two-year OS and RFS for patients with ≤ 10% versus > 10% cellularity at D14BM was 60.6% [95% confidence interval (CI), 50.8%-72.2%] versus 32.5% [95% CI, 23.0%-45.8%], and 51.9% [95% CI, 41.9%-64.3%] versus 28.8% [95% CI, 19.1%-43.4%], respectively [P = .0003 for OS and .002 for RFS].

Conclusion

Rapid PBC after 7+3 induction showed a significant improvement in specificity compared with D14BM, with similar sensitivity. Neither of these methods were reliably specific tools for the decision of early reinduction, despite their prognostic value. Our findings indicate that morphological cellularity in D14BM is an independent prognostic factor for OS and RFS, regardless of blast percentage, and that ≤ 10% cellularity defines D14BM hypoplasia.  相似文献   
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《肿瘤防治研究》2020,(7):517-523
Objective To investigate the correlation of rib 99mTc-MDP foci on whole-body bone scan with clinical variables and rib metastases in nasopharyngeal carcinoma(NPC) patients, and to screen the risk factors of rib metastases. Methods We retrospectively reviewed 312 NPC patients with rib 99mTc-MDP foci on wholebody bone scan. Chi-square test and logistic regression were performed to evaluate the correlation between clinical variables and rib metastases. Results In all 312 NPC patients, rib metastases were associated with T stage, skull base bone invasion, other bone metastasis, number of rib foci, lateral localization on rib and foci type (P<0.01), and the risk factors of rib metastasis included skull base bone invasion, other bone metastases, lateral localization on rib and foci type (P<0.05). In 176 patients with pure rib foci, rib metastases were closely related to T stage, skull base bone invasion, other bone metastasis, number of rib foci and lateral localization on rib (P<0.05), while only lobar distribution (P=0.029) was the effective risk factor. In 198 patients with single rib focus, rib metastases were affected by skull base bone invasion and foci type (P<0.01), while only foci type (P=0.000) was the effective risk factor. In all 566 rib foci, uptake level and localization on rib were the effective risk factors of rib metastases(P<0.01). Conclusion In NPC patients with rib foci on whole body bone scan, the effective risk factors of rib metastases include skull base bone invasion, other bone metastases, lateral localization on rib, foci type, uptake level and anterior and posterior localization on rib. Follow up should be the main way for the pure rib foci on unilateral ribs. For multiples rib foci on bilateral ribs or single rib focus combined with other bones foci, additional image modalities should be required to exclude bone metastasis. © 2020, CHINA RESEARCH ON PREVENTION AND TREATMENT. All rights reserved.  相似文献   
10.
Context: Magnetic Resonance Imaging (MRI) is an essential diagnostic tool for neuroimaging tissues such as the spinal cord. Unfortunately, the use of MRI may be limited in ventilated patients, who cannot maintain the supine position in spontaneous breathing for the whole duration of the exam (i.e. neuro-muscular patients with diaphragm involvement). The use of MRI-compatible ventilator during MRI could be a solution but they are not universally available. Furthermore, their performances are not up to those of the conventional ones and they are not always compatible with Non Invasive Ventilation (NIV).

Findings: This case report describes an easy and low-cost solution to ventilate a patient non-invasively during the MRI procedure. The patient in this case was a 45-yr-old man, wheelchair-dependent and chronically ventilated in NIV with a forced vital capacity in supine position of 370?ml (10% of predicted normal), affected by Arnold-Chiari Syndrome, and in need of a MRI diagnostic control.

Conclusion: The technique proposed, that does not affect the MRI images quality, consists in ventilating the patient using a simple nonmetallic Ventilation Bag, operated by a Respiratory Therapist. This has been proven a useful and economical solution for ventilatory support during MRI for a respiratory-dependent patient with Arnold-Chiari Syndrome.  相似文献   
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