[Selection of placement position of support points for early and mid-term mechanical repair of femoral head necrosis].

OBJECTIVE: To investigate the clinical efficacy of the placement of the main mechanical support points in the early and middle stages of mechanical repair of femoral head necrosis in preventing collapse of the femoral head. METHODS: A retrospective analysis was performed for 17 cases 22 hips of non-traumatic femoral head necrosis in the early and middle stages from June 2018 to June 2019, including 14 males 18 hips and 3 females 4 hips, aged 34 to 47 years old. Among them, 6 cases were hormonal, 8 were alcoholic and 3 were idiopathic. According to China-Japan Friendship Hospital(CJFH) classification, 9 hip were type L1, 8 were L2, 5 were L3. All cases were given dead bone scraping, autologous iliac granules pressed bone grafting, and allogeneic fibula column support treatment. After surgery, Sanqi Jiegu Pill() was administered orally for 3 months. X-rays of both hips were performed after surgery and follow-up, and the clinical efficacy was evaluated by hip Harris score before and after surgery. RESULTS: All cases were followed up for 24 to 38 months. The Harris score of 22 hips increased from 58 to 77 preoperative to 68 to 94 at the final follow-up. At the final follow-up, 3 hips were excellent, 11 hips were good, 3 hips were acceptable, 5 hips were poor. Two hips of L2 type progressed to ARCO ⅢB stage and continued to be observed, 2 hips of L2 type and 2 hips of L3 type progressed to ARCO Ⅳ stage, and received total hip replacement, and 1 hip infection at 3 months after surgery was given a cement spacer. CONCLUSION: Based on CJFH classification, collapse can be predicted to a certain extent according to the area, volume, location and human biological characteristics of osteonecrosis, and the main mechanical support points are found on this basis to prevent collapse.

A single dose of an adenovirus-vectored vaccine provides protection against SARS-CoV-2 challenge.

The unprecedented coronavirus disease 2019 (COVID-19) epidemic has created a worldwide public health emergency, and there is an urgent need to develop an effective vaccine to control this severe infectious disease. Here, we find that a single vaccination with a replication-defective human type 5 adenovirus encoding the SARS-CoV-2 spike protein (Ad5-nCoV) protect mice completely against mouse-adapted SARS-CoV-2 infection in the upper and lower respiratory tracts. Additionally, a single vaccination with Ad5-nCoV protects ferrets from wild-type SARS-CoV-2 infection in the upper respiratory tract. This study suggests that the mucosal vaccination may provide a desirable protective efficacy and this delivery mode is worth further investigation in human clinical trials.

Integrin ß1 Promotes Peripheral Entry by Rabies Virus.

Rabies virus (RABV) is a widespread pathogen that causes fatal disease in humans and animals. It has been suggested that multiple host factors are involved in RABV host entry. Here, we showed that RABV uses integrin ß1 (ITGB1) for cellular entry. RABV infection was drastically decreased after ITGB1 short interfering RNA knockdown and moderately increased after ITGB1 overexpression in cells. ITGB1 directly interacts with RABV glycoprotein. Upon infection, ITGB1 is internalized into cells and transported to late endosomes together with RABV. The infectivity of cell-adapted RABV in cells and street RABV in mice was neutralized by ITGB1 ectodomain soluble protein. The role of ITGB1 in RABV infection depends on interaction with fibronectin in cells and mice. We found that Arg-Gly-Asp (RGD) peptide and antibody to ITGB1 significantly blocked RABV infection in cells in vitro and street RABV infection in mice via intramuscular inoculation but not the intracerebral route. ITGB1 also interacts with nicotinic acetylcholine receptor, which is the proposed receptor for peripheral RABV infection. Our findings suggest that ITGB1 is a key cellular factor for RABV peripheral entry and is a potential therapeutic target for postexposure treatment against rabies.IMPORTANCE Rabies is a severe zoonotic disease caused by rabies virus (RABV). However, the nature of RABV entry remains unclear, which has hindered the development of therapy for rabies. It is suggested that modulations of RABV glycoprotein and multiple host factors are responsible for RABV invasion. Here, we showed that integrin ß1 (ITGB1) directly interacts with RABV glycoprotein, and both proteins are internalized together into host cells. Differential expression of ITGB1 in mature muscle and cerebral cortex of mice led to A-4 (ITGB1-specific antibody), and RGD peptide (competitive inhibitor for interaction between ITGB1 and fibronectin) blocked street RABV infection via intramuscular but not intracerebral inoculation in mice, suggesting that ITGB1 plays a role in RABV peripheral entry. Our study revealed this distinct cellular factor in RABV infection, which may be an attractive target for therapeutic intervention.

[Spatio-Temporal Patterns and Environmental Risk of Endocrine Disrupting Chemicals in the Liuxi River].

This study aimed to investigate the occurrence and spatio-temporal distribution of 4-tert-octylphenol (4-t-OP), 4-nonylphenol (4-NP), triclosan (TCS), estrone (E1), 17ß-estradiol (E2), and bisphenol-A (BPA) as endocrine disrupting chemicals (EDCs) in the water of the Liuxi River and to evaluate the risks for estrogenic activity. The results showed that EDCs had been detected at the 14 monitoring sites and the total concentration ranged from 26.07 ng·L-1 to 7109.5 ng·L-1, with the highest contribution rate coming from 4-NP (78.62%), followed by BPA (11.91%), and the other four EDCs (≤ 4.92%). On a spatial and temporal scale, the EDC contents increased longitudinally from upstream to downstream, especially in the heavily-polluted Baiyun section where the water quality was lower than level Ⅴ. The EDC contents in the tributaries were much higher than those in the main channels. Influenced by the monsoon precipitation, the contents of 4-NP, 4-t-OP, and total EDCs in the rainy season were significantly (P<0.05) higher than those in the dry season, while the seasonal changes of E1 and E2 followed the opposite tendency. A Pearson correlation analysis showed that DO was significantly negatively correlated with all the EDCs, suggesting that the EDCs and reductive organic pollutants might coexist. As TN, TP, NH4+-N, permanganate index, and EC were significantly positively correlated with E1, E2, BPA, and TCS but not obviously correlated with 4-NP (P>0.05), we presumed that the pollution source of E1, E2, BPA, and TCS might be the same with nitrogen and phosphorus nutrition, originating from the point source emission of the domestic sewage, industrial, and agricultural wastewater. In contrast, 4-NP and 4-t-OP more likely originated from the non-point source pollution from agriculture. RDA results showed that the variation of the EDCs contents by season was more obvious than that in space (RDA1 56.14%>RDA2 14.20%), which was much more influenced by 4-NP in the rainy season and by BPA in the dry season. As E1, E2, and TCS were positively correlated with the Cu, Zn, cyanide, and fecal coliform, these three target compounds could be used to indicate the multiple pollution components for water quality. Compared with the worldwide reported EDC contents in waters, 4-NP, BPA, and TCS contents in the middle and lower reaches of the Liuxi River were at higher levels, while E1, E2, and 4-t-OP were at the middle and lower levels. The risk assessment for estrogenic activity showed that the RQ values in the middle and lower reaches of the Liuxi River were all greater than 1, indicating that the downstream river sections were under high risk for estrogenic activity. As a result, appropriate precautions are needed to improve environmental management.

A recombinant VSV-vectored MERS-CoV vaccine induces neutralizing antibody and T cell responses in rhesus monkeys after single dose immunization.

Middle East respiratory syndrome coronavirus (MERS-CoV) has been a highly threatening zoonotic pathogen since its outbreak in 2012. Similar to SARS-CoV, MERS-CoV belongs to the coronavirus family and can induce severe respiratory symptoms in humans, with an average case fatality rate of 35% according to the World Health Organization. Spike (S) protein of MERS-CoV is immunogenic and can induce neutralizing antibodies, thus is a potential major target for vaccine development. Here we constructed a chimeric virus based on the vesicular stomatitis virus (VSV) in which the G gene was replaced by MERS-CoV S gene (VSVΔG-MERS). The S protein efficiently incorporated into the viral envelope and mediated cell entry through binding its receptor, human DPP4. Knockdown of clathrin expression by siRNA drastically abrogated the infection of VSVΔG-MERS in Vero cells. Furthermore, in animal studies, the recombinant virus induced neutralizing antibodies and T cell responses in rhesus monkeys after a single intramuscular or intranasal immunization dose. Our findings indicate the potential of the chimeric VSVΔG-MERS as a rapid response vaccine candidate against emerging MERS-CoV disease.

Genetically modified rabies virus-vectored Ebola virus disease vaccines are safe and induce efficacious immune responses in mice and dogs.

Ebola viruses (EBOVs) are zoonotic pathogens that cause EBOV disease (EVD) with high case fatality in humans. Currently, EVD vaccines are still under development in several countries. Here, we generated two recombinant rabies viruses (RABVs), rERAG333E/ZGP and rERAG333E/SGP, expressing the Zaire EBOV glycoprotein (ZGP) or Sudan EBOV glycoprotein (SGP) gene based on a modified ERA vaccine strain (rERAG333E) vector platform. The recombinant RABVs retained growth properties similar to those of the vector virus in BSR cell culture and efficiently expressed ZGP or SGP. After intracerebral (i.c.) inoculation with rERAG333E/ZGP or rERAG333E/SGP, all adult mice showed no signs of disease or weight loss and suckling mice maintained similar survivorship curve as those mice inoculated with control vector rERAG333E, demonstrating that ZGP or SGP expression did not increase the virulence of the vector. Mouse immunization studies showed that vaccination with rERAG333E/ZGP and rERAG333E/SGP induced Zaire or Sudan EBOV neutralizing antibody (VNA) responses and IgG, IgG2a responses to ZGP or SGP, suggesting their potential as oral or inactivated bivalent vaccines against rabies and EVD. Most importantly, all dogs immunized orally with rERAG333E/ZGP developed long-lasting ZEBOV and RABV VNA responses with or without previous rabies vaccine immunization history. Live rERAG333E with EBOV GP thus appear to have the potential to be oral vaccines for free-roaming animals in endemic areas of EVD and rabies, and may serve as inactivated vaccines for use in humans.

Genetically modified rabies virus ERA strain is safe and induces long-lasting protective immune response in dogs after oral vaccination.

Oral immunization in free-roaming dogs is one of the most practical approaches to prevent rabies for developing countries. The safe, efficient and long-lasting protective oral rabies vaccine for dogs is highly sought. In this study, rabies virus (RABV) Evelyn-Rokitnicki-Abelseth (ERA) strain wild-type (rERA) and a genetically modified type (rERAG333E) containing a mutation from arginine to glutamic acid at residue 333 of glycoprotein (G333E) were generated by reverse genetic. The recombinant virus rERAG333E retained growth properties of similar to the parent strain rERA in BHK-21 cell culture. The G333E mutation showed genetic stability during passage into neuroblastoma cells and in the brains of suckling mice and was significantly reduced the virulence of rERA in mice. rERAG333E was immunogenic in dogs by intramuscular inoculation. Mice orally vaccinated with rERAG333E induced strong and one year longer virus neutralizing antibodies (VNA) to RABV, and were completely protected from challenge with lethal street virus at 12months after immunization. Dogs received oral vaccination with rERAG333E induced strong protective RABV VNA response, which lasted for over 3years, and moderate saliva RABV-specific IgA. Moreover, sizeable booster responses to RABV VNA were induced by a second oral dose 1year after the first dose. These results demonstrated that the genetically modified ERA vaccine strain has the potential to serve as a safe and efficient oral live vaccine against rabies in dogs.

Recombinant canine distemper virus serves as bivalent live vaccine against rabies and canine distemper.

Effective, safe, and affordable rabies vaccines are still being sought. Attenuated live vaccine has been widely used to protect carnivores from canine distemper. In this study, we generated a recombinant canine distemper virus (CDV) vaccine strain, rCDV-RVG, expressing the rabies virus glycoprotein (RVG) by using reverse genetics. The recombinant virus rCDV-RVG retained growth properties similar to those of vector CDV in Vero cell culture. Animal studies demonstrated that rCDV-RVG was safe in mice and dogs. Mice inoculated intracerebrally or intramuscularly with rCDV-RVG showed no apparent signs of disease and developed a strong rabies virus (RABV) neutralizing antibody response, which completely protected mice from challenge with a lethal dose of street virus. Canine studies showed that vaccination with rCDV-RVG induced strong and long-lasting virus neutralizing antibody responses to RABV and CDV. This is the first study demonstrating that recombinant CDV has the potential to serve as bivalent live vaccine against rabies and canine distemper in animals.

[Insertion of glycoprotein gene between P and M gene influences the pathogenicity of the rabies virus Flury LEP].

OBJECTIVE: To study the biological characteristics and pathogenicity of a recombinant rabies virus Flury LEP (low egg passage) that has two glycoprotein genes (G gene). METHODS: By using reverse genetics techniques, we constructed a recombinant virus Flury LEP that has an additional G gene between P and M gene (rLEP-PGM). Then we studied the biological characteristics of the recombinant virus and its pathogenicity on mice. RESULTS: The in vitro growth characteristic of rLEP-PGM were similar to the LEP strain. Western blot analysis of glycoprotein expression showed that the glycoprotein expression level of rLEP-PGM was 1.5 times higher than LEP. The LD50 of rLEP-PGM and LEP was 3 FFU and 1 FFU by intracerebral injection. However, the LD50 of intramuscular injection was 4 x 10(4) Lg FFU and 3.2 x 10(5) Lg FFU, respectively. CONCLUSION: Insertion of an additional G gene between P and M gene can significantly raise the expression level of glycoprotein and enhance the ability to invade central nervous system from peripheral sites.