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Autophagy plays an important role in the infectious processes of diverse pathogens. For instance, cellular autophagy could be harnessed by viruses to facilitate replication. However, it is still uncertain about the interplay of autophagy and swine acute diarrhea syndrome coronavirus (SADS-CoV) in cells. In this study, we reported that SADS-CoV infection could induce a complete autophagy process both in vitro and in vivo, and an inhibition of autophagy significantly decreased SADS-CoV production, thus suggesting that autophagy facilitated the replication of SADS-CoV. We found that ER stress and its downstream IRE1 pathway were indispensable in the processes of SADS-CoV-induced autophagy. We also demonstrated that IRE1-JNK-Beclin 1 signaling pathway, neither PERK-EIF2S1 nor ATF6 pathways, was essential during SADS-CoV-induced autophagy. Importantly, our work provided the first evidence that expression of SADS-CoV PLP2-TM protein induced autophagy through the IRE1-JNK-Beclin 1 signaling pathway. Furthermore, the interaction of viral PLP2-TMF451-L490 domain and substrate-binding domain of GRP78 was identified to activate the IRE1-JNK-Beclin 1 signaling pathway, and thus resulting in autophagy, and in turn, enhancing SADS-CoV replication. Collectively, these results not only showed that autophagy promoted SADS-CoV replication in cultured cells, but also revealed that the molecular mechanism underlying SADS-CoV-induced autophagy in cells.
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Chaperón BiP del Retículo Endoplásmico , Papaína , Papaína/metabolismo , Beclina-1 , Péptido Hidrolasas/metabolismo , Autofagia , Transducción de Señal , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismoRESUMEN
Swine acute diarrhea syndrome coronavirus (SADS-CoV), an emerging Alpha-coronavirus, brings huge economic loss in swine industry. Interferons (IFNs) participate in a frontline antiviral defense mechanism triggering the activation of numerous downstream antiviral genes. Here, we demonstrated that TRIM25 overexpression significantly inhibited SADS-CoV replication, whereas TRIM25 deficiency markedly increased viral yield. We found that SADS-CoV N protein suppressed interferon-beta (IFN-ß) production induced by Sendai virus (SeV) or poly(I:C). Moreover, we determined that SADS-CoV N protein interacted with RIG-I N-terminal two caspase activation and recruitment domains (2CARDs) and TRIM25 coiled-coil dimerization (CCD) domain. The interaction of SADS-CoV N protein with RIG-I and TRIM25 caused TRIM25 multimerization inhibition, the RIG-I-TRIM25 interaction disruption, and consequent the IRF3 and TBK1 phosphorylation impediment. Overexpression of SADS-CoV N protein facilitated the replication of VSV-GFP by suppressing IFN-ß production. Our results demonstrate that SADS-CoV N suppresses the host IFN response, thus highlighting the significant involvement of TRIM25 in regulating antiviral immune defenses.
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Alphacoronavirus , Proteínas de la Nucleocápside , Animales , Porcinos , Alphacoronavirus/metabolismo , Interferones/genética , Proteína 58 DEAD Box/metabolismoRESUMEN
To better understand the vulnerabilities of pregnant women during the COVID-19 pandemic, we conducted a comprehensive, retrospective cohort study to assess differences in immune responses to SARS-CoV-2 infection between pregnant and non-pregnant women. Nasopharyngeal swabs and serum specimens from 90 pregnant and 278 age-matched non-pregnant women were collected from 15 March 2020 to 23 July 2021 at NewYork-Presbyterian Queens Hospital in New York City. Multiplex reverse transcription polymerase chain reaction, neutralizing antibody, and cytokine array assays were used to assess the incidence, viral load, antibody titers and profiles, and examine cytokine expression patterns. Our results show a lower incidence of SARS-CoV-2 infection in pregnant women compared with non-pregnant women. Pregnant women infected with SARS-CoV-2 exhibited a substantially lower viral load. In addition, the levels of both anti-spike protein receptor-binding domain IgG neutralizing antibodies and anti-N Protein IgG were elevated in pregnant women. Finally, cytokine profiling revealed differential expression of leptin across cohorts. These findings suggest that pregnancy is associated with distinct immune and virological responses to SARS-CoV-2 infection, characterized by lower infection rates, substantially lower viral loads, and enhanced antibody production. Differential cytokine expression indicates unique immune modulation in pregnant women.
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Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Citocinas , Complicaciones Infecciosas del Embarazo , SARS-CoV-2 , Carga Viral , Humanos , Femenino , Embarazo , COVID-19/inmunología , COVID-19/virología , COVID-19/sangre , COVID-19/epidemiología , Citocinas/sangre , Citocinas/metabolismo , Adulto , SARS-CoV-2/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Complicaciones Infecciosas del Embarazo/virología , Complicaciones Infecciosas del Embarazo/inmunología , Complicaciones Infecciosas del Embarazo/sangre , Estudios Retrospectivos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismoRESUMEN
The Omicron variant of SARS-CoV-2 has become dominant in most countries and has raised significant global health concerns. As a global commerce center, New York, New York, USA, constantly faces the risk for multiple variant introductions of SARS-CoV-2. To elucidate the introduction and transmission of the Omicron variant in the city of New York, we created a comprehensive genomic and epidemiologic analysis of 392 Omicron virus specimens collected during November 25-December 11, 2021. We found evidence of 4 independent introductions of Omicron subclades, including the Omicron subclade BA.1.1 with defining substitution of R346K in the spike protein. The continuous genetic divergence within each Omicron subclade revealed their local community transmission and co-circulation in New York, including both household and workplace transmissions supported by epidemiologic evidence. Our study highlights the urgent need for enhanced genomic surveillance and effective response planning for better prevention and management of emerging SARS-CoV-2 variants.
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COVID-19 , Humanos , New York/epidemiología , COVID-19/epidemiología , SARS-CoV-2/genética , ComercioRESUMEN
Being in the epicenter of the COVID-19 pandemic, our lab tested 193,054 specimens for SARS-CoV-2 RNA by diagnostic multiplex reverse transcription polymerase chain reaction (mRT-PCR) starting in March 2020, of which 17,196 specimens resulted positive. To investigate the dynamics of virus molecular evolution and epidemiology, whole genome amplification (WGA) and Next Generation Sequencing (NGS) were performed on 9516 isolates. 7586 isolates with a high quality were further analyzed for the mutation frequency and spectrum. Lastly, we evaluated the utility of the mRT-PCR detection pattern among 26 reinfected patients with repeat positive testing three months after testing negative from the initial infection. Our results show a continuation of the genetic divergence in viral genomes. Furthermore, our results indicate that independent mutations in the primer and probe regions of the nucleocapsid gene amplicon and envelope gene amplicon accumulate over time. Some of these mutations correlate with the changes of detection pattern of viral targets of mRT-PCR. Our data highlight the significance of a continuous genetic divergence on a gene amplification-based assay, the value of the mRT-PCR detection pattern for complementing the clinical diagnosis of reinfection, and the potential for WGA and NGS to identify mutation hotspots throughout the entire viral genome to optimize the design of the PCR-based gene amplification assay.
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COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/genética , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos , Humanos , Reacción en Cadena de la Polimerasa Multiplex , Pandemias , ARN Viral/análisis , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2/genética , Sensibilidad y EspecificidadRESUMEN
We identified co-infection with 4 species of mycobacteria in a woman in New York, New York, USA, by using next-generation sequencing. This procedure is useful for identifying co-infections with multiple mycobacteria, tracing the geographic origin of strains, investigating transmission dynamics in susceptible populations, and gaining insight into prevention and control.
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Coinfección , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mycobacterium/genética , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Micobacterias no Tuberculosas/genéticaRESUMEN
Molecular testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the gold standard for diagnosis of coronavirus disease 2019 (COVID-19), but the clinical performance of these tests is still poorly understood, particularly with regard to disease course, patient-specific factors, and viral shedding. From 10 March to 1 May 2020, NewYork-Presbyterian laboratories performed 27,377 SARS-CoV-2 molecular assays from 22,338 patients. Repeat testing was performed for 3,432 patients, of which 2,413 had initial negative and 802 had initial positive results. Repeat-tested patients were more likely to have severe disease and low viral loads. The negative predictive value of the first-day result among repeat-tested patients was 81.3% The clinical sensitivity of SARS-CoV-2 molecular assays was estimated between 58% and 96%, depending on the unknown number of false-negative results in single-tested patients. Conversion to negative was unlikely to occur before 15 to 20 days after initial testing or 20 to 30 days after the onset of symptoms, with 50% conversion occurring at 28 days after initial testing. Conversion from first-day negative to positive results increased linearly with each day of testing, reaching 25% probability in 20 days. Sixty patients fluctuated between positive and negative results over several weeks, suggesting that caution is needed when single-test results are acted upon. In summary, our study provides estimates of the clinical performance of SARS-CoV-2 molecular assays and suggests time frames for appropriate repeat testing, namely, 15 to 20 days after a positive test and the same day or next 2 days after a negative test for patients with high suspicion for COVID-19.
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Betacoronavirus/aislamiento & purificación , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Pruebas Diagnósticas de Rutina/métodos , Neumonía Viral/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus/genética , COVID-19 , Prueba de COVID-19 , Niño , Preescolar , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/virología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , New York , Pandemias , Neumonía Viral/patología , Neumonía Viral/virología , Valor Predictivo de las Pruebas , SARS-CoV-2 , Sensibilidad y Especificidad , Carga Viral , Adulto JovenRESUMEN
A surge of patients with coronavirus disease 2019 (COVID-19) presenting to New York City hospitals in March 2020 led to a sharp increase in blood culture utilization, which overwhelmed the capacity of automated blood culture instruments. We sought to evaluate the utilization and diagnostic yield of blood cultures during the COVID-19 pandemic to determine prevalence and common etiologies of bacteremia and to inform a diagnostic approach to relieve blood culture overutilization. We performed a retrospective cohort analysis of 88,201 blood cultures from 28,011 patients at a multicenter network of hospitals within New York City to evaluate order volume, positivity rate, time to positivity, and etiologies of positive cultures in COVID-19. Ordering volume increased by 34.8% in the second half of March 2020 compared to the level in the first half of the month. The rate of bacteremia was significantly lower among COVID-19 patients (3.8%) than among COVID-19-negative patients (8.0%) and those not tested (7.1%) (P < 0.001). COVID-19 patients had a high proportion of organisms reflective of commensal skin microbiota, which, when excluded, reduced the bacteremia rate to 1.6%. More than 98% of all positive cultures were detected within 4 days of incubation. Bloodstream infections are very rare for COVID-19 patients, which supports the judicious use of blood cultures in the absence of compelling evidence for bacterial coinfection. Clear communication with ordering providers is necessary to prevent overutilization of blood cultures during patient surges, and laboratories should consider shortening the incubation period from 5 days to 4 days, if necessary, to free additional capacity.
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Bacteriemia/diagnóstico , Bacteriemia/epidemiología , Cultivo de Sangre/estadística & datos numéricos , Coinfección/diagnóstico , Coinfección/epidemiología , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/epidemiología , Neumonía Viral/complicaciones , Neumonía Viral/epidemiología , Betacoronavirus/aislamiento & purificación , COVID-19 , Hospitales , Humanos , Ciudad de Nueva York/epidemiología , Pandemias , Prevalencia , Estudios Retrospectivos , SARS-CoV-2RESUMEN
To limit introduction of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), the United States restricted travel from China on February 2, 2020, and from Europe on March 13. To determine whether local transmission of SARS-CoV-2 could be detected, the New York City (NYC) Department of Health and Mental Hygiene (DOHMH) conducted deidentified sentinel surveillance at six NYC hospital emergency departments (EDs) during March 1-20. On March 8, while testing availability for SARS-CoV-2 was still limited, DOHMH announced sustained community transmission of SARS-CoV-2 (1). At this time, twenty-six NYC residents had confirmed COVID-19, and ED visits for influenza-like illness* increased, despite decreased influenza virus circulation. The following week, on March 15, when only seven of the 56 (13%) patients with known exposure histories had exposure outside of NYC, the level of community SARS-CoV-2 transmission status was elevated from sustained community transmission to widespread community transmission (2). Through sentinel surveillance during March 1-20, DOHMH collected 544 specimens from patients with influenza-like symptoms (ILS)§ who had negative test results for influenza and, in some instances, other respiratory pathogens.¶ All 544 specimens were tested for SARS-CoV-2 at CDC; 36 (6.6%) tested positive. Using genetic sequencing, CDC determined that the sequences of most SARS-CoV-2-positive specimens resembled those circulating in Europe, suggesting probable introductions of SARS-CoV-2 from Europe, from other U.S. locations, and local introductions from within New York. These findings demonstrate that partnering with health care facilities and developing the systems needed for rapid implementation of sentinel surveillance, coupled with capacity for genetic sequencing before an outbreak, can help inform timely containment and mitigation strategies.
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Betacoronavirus/genética , Betacoronavirus/aislamiento & purificación , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/virología , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Neumonía Viral/diagnóstico , Neumonía Viral/virología , Vigilancia de Guardia , Adolescente , Adulto , Anciano , COVID-19 , Niño , Preescolar , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones por Coronavirus/epidemiología , Servicio de Urgencia en Hospital , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Ciudad de Nueva York/epidemiología , Pandemias , Neumonía Viral/epidemiología , SARS-CoV-2 , Análisis de Secuencia , Enfermedad Relacionada con los Viajes , Adulto JovenRESUMEN
A large number of imported cases of Zika virus infection and the potential for transmission by Aedes albopictus mosquitoes prompted the New York City Department of Health and Mental Hygiene to conduct sentinel, enhanced passive, and syndromic surveillance for locally acquired mosquitoborne Zika virus infections in New York City, NY, USA, during June-October 2016. Suspected case-patients were those >5 years of age without a travel history or sexual exposure who had >3 compatible signs/symptoms (arthralgia, fever, conjunctivitis, or rash). We identified 15 suspected cases and tested urine samples for Zika virus by using real-time reverse transcription PCR; all results were negative. We identified 308 emergency department visits for Zika-like illness, 40,073 visits for fever, and 17 unique spatiotemporal clusters of visits for fever. We identified no evidence of local transmission. Our experience offers possible surveillance tools for jurisdictions concerned about local mosquitoborne Zika virus or other arboviral transmission.
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Culicidae/virología , Vigilancia de Guardia , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/epidemiología , Virus Zika/aislamiento & purificación , Adolescente , Adulto , Animales , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ciudad de Nueva York/epidemiología , Embarazo , Adulto JovenRESUMEN
We describe the first case of cat-to-human transmission of influenza A(H7N2), an avian-lineage influenza A virus, that occurred during an outbreak among cats in New York City animal shelters. We describe the public health response and investigation.
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Brotes de Enfermedades/veterinaria , Subtipo H7N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/transmisión , Infecciones por Orthomyxoviridae/veterinaria , Animales , Anticuerpos Antivirales/sangre , Gatos , Humanos , Subtipo H7N2 del Virus de la Influenza A/genética , Virus de la Influenza A/inmunología , Gripe Humana/epidemiología , Gripe Humana/virología , Ciudad de Nueva York/epidemiología , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/virología , Reacción en Cadena de la PolimerasaRESUMEN
An outbreak of influenza A(H7N2) virus in cats in a shelter in New York, NY, USA, resulted in zoonotic transmission. Virus isolated from the infected human was closely related to virus isolated from a cat; both were related to low pathogenicity avian influenza A(H7N2) viruses detected in the United States during the early 2000s.
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Enfermedades de los Gatos/epidemiología , Brotes de Enfermedades , Genoma Viral , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Subtipo H7N2 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Zoonosis/epidemiología , Animales , Antígenos Virales/química , Antígenos Virales/genética , Antígenos Virales/metabolismo , Sitios de Unión , Aves , Enfermedades de los Gatos/transmisión , Enfermedades de los Gatos/virología , Gatos , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Vivienda para Animales , Humanos , Subtipo H7N2 del Virus de la Influenza A/clasificación , Subtipo H7N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/transmisión , Gripe Aviar/virología , Modelos Moleculares , New York/epidemiología , Polisacáridos/química , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Receptores Virales/química , Receptores Virales/genética , Receptores Virales/metabolismo , Veterinarios , Zoonosis/transmisión , Zoonosis/virologíaRESUMEN
Serologic evaluation for Zika virus (ZIKV) infection currently includes an initial screen using an anti-ZIKV IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) followed by supplemental testing of specimens with nonnegative results by a plaque reduction neutralization test (PRNT). We compared the performance characteristics of three ELISAs for the detection of IgM class antibodies to ZIKV, including the Centers for Disease Control and Prevention (CDC) Zika MAC-ELISA, the InBios ZIKV Detect MAC-ELISA, and the Euroimmun anti-Zika Virus IgM ELISA. Additionally, we present our initial experiences with ZIKV serologic testing from a national reference laboratory perspective. Using both retrospectively and prospectively collected specimens from patients with possible ZIKV infection, we show that the CDC and InBios MAC-ELISAs perform comparably to each other, with positive agreement, negative agreement, and interrater kappa values ranging from 87.5% to 93.1%, 95.7% to 98.5%, and 0.52 to 0.83, respectively. In contrast, comparison of the Euroimmun ZIKV ELISA to either the CDC or InBios MAC-ELISAs resulted in positive agreement, negative agreement, and interrater kappa values ranging from 17.9% to 42.9%, 91.7% to 98.6%, and 0.10 to 0.39, respectively. Among the 19 prospective samples submitted for PRNT, nine were negative, eight specimens had neutralizing antibodies to a flavivirus (unable to be identified), and one sample each was confirmed for ZIKV or dengue virus infection. This study highlights the ongoing challenges associated with serologic diagnosis of ZIKV infection. Although the availability of a commercial serologic test for ZIKV has greatly expanded the national capacity for such testing, the need to further characterize and improve these assays, particularly with regard to specificity, remains.
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Anticuerpos Antivirales/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina M/sangre , Pruebas Serológicas/métodos , Infección por el Virus Zika/diagnóstico , Virus Zika/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Factores Inmunológicos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Embarazo , Estudios Prospectivos , Estudios Retrospectivos , Adulto JovenRESUMEN
Mutations in Wnt receptor LRP5/6 and polymorphism in Wnt-regulated transcription factor TCF7L2 are associated with dysregulation of glucose metabolism. However, it is not clear whether Wnt antagonist Dickkopf (Dkk) has a significant role in the regulation of glucose metabolism. Here, we identified small-molecule inhibitors of Wnt antagonist Dkk through molecular modeling, computation-based virtual screens, and biological assays. One of the Dkk inhibitors reduced basal blood-glucose concentrations and improved glucose tolerance in mice. This Dkk inhibitor appeared to act through DKK2 because the inhibitor exerted no additional effects on glucose metabolism in the Dkk2(-/-) mice. Our study of Dkk2(-/-) mice showed that DKK2 deficiency was associated with increased hepatic glycogen accumulation and decreased hepatic glucose output. DKK2 deficiency did not cause in increase in insulin production but resulted in increased Wnt activity and GLP1 production in the intestines. Given that the Dkk inhibitor improved glucose tolerance in a murine model of type 2 diabetes (db/db), we suggest that DKK2 may be a potential therapeutic target for treating type 2 diabetes.
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Regulación de la Expresión Génica , Glucosa/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas Wnt/metabolismo , Animales , Diabetes Mellitus Tipo 2/metabolismo , Prueba de Tolerancia a la Glucosa , Glucógeno/metabolismo , Cinética , Hígado/metabolismo , Ratones , Ratones Transgénicos , Modelos Genéticos , Polimorfismo Genético , Transducción de Señal , Programas Informáticos , Proteína 2 Similar al Factor de Transcripción 7/metabolismoRESUMEN
Swine acute diarrhea syndrome coronavirus (SADS-CoV) is an emerging alpha-coronavirus that causes diarrhea in piglets and results in serious economic losses. During SADS-CoV infection, the spike protein (S) serves as a crucial structural component of the virion, interacting with receptors and eliciting the production of neutralizing antibodies. Due to the potential risk of zoonotic transmission of SADS-CoV, the identification and screening of epitopes on the S glycoproteins will be crucial for development of sensitive and specific diagnostic tools. In this study, we immunized BALB/c mice with recombinant SADS-CoV S trimer protein and generated two S1-specific monoclonal antibodies (mAbs): 8D6 and 6E9, which recognized different linear B-cell epitopes. The minimal fragment recognized by mAb 8D6 was mapped to 311NPDQRD316, the minimal fragment recognized by mAb 6E9 was mapped to 492ARFVDRL498. Homology analysis of the regions corresponding to 13 typical strains of different SADS-CoV subtypes showed high conservation of these two epitopes. These findings contribute to a deeper understanding of the structure of the SADS-CoV S protein, which is valuable for vaccine design and holds potential for developing diagnostic methods to detect SADS-CoV.
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In the original publication [...].
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OBJECTIVES: At present, a variety of posterior lumbar internal fixation implantation methods have been developed, which makes it difficult for spine surgeons to choose. The stress distribution of the internal fixation system is one of the important indexes to evaluate these technologies. Common insertion technologies include Roy Camille, Magerl, Krag, AO, and Weinstein insertion techniques. This study aimed to compare the distribution of von Mises stresses in different screw fixation systems established by these insertion technologies. METHODS: Here, the three-dimensional finite element (FE) method was selected to evaluate the postoperative stress distribution of internal fixation. Following different pedicle screw insertion techniques, five single-segment transforaminal lumbar interbody fusion (TLIF) models were established after modeling and validation of the L1-S1 vertebrae FE model. RESULTS: By analyzing the data, we found that stress concentration phenomenon was in all the models. Additionally, Roy-Camille, Krag, AO, and Weinstein insertion techniques led to the great stress on lumbar vertebra, intervertebral disc, and screw-rod fixation systems. Therefore, we hope that the results can provide ideas for clinical work and development of pedicle screws in the future. It is worth noting that flexion, unaffected side lateral bending, and affected side axial rotation should be limited for the patients with cages implanted. CONCLUSIONS: Overall, our method obtained the results that Magerl insertion technique was the relatively safe approach for pedicle screw implantation due to its relatively dispersive stress in TLIF models.
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Fijación Interna de Fracturas , Vértebras Lumbares , Tornillos Pediculares , Fusión Vertebral , Estrés Mecánico , Fusión Vertebral/métodos , Vértebras Lumbares/cirugía , Análisis de Elementos Finitos , Fijadores Internos , Fijación Interna de Fracturas/instrumentación , Fijación Interna de Fracturas/métodosRESUMEN
Swine acute diarrhea syndrome coronavirus (SADS-CoV) is an emerging porcine intestinal coronavirus that can cause acute diarrhea, vomiting, rapid weight loss, and high mortality in newborn piglets. Cholesterol 25-hydroxylase (CH25H) is a molecular mediator of innate antiviral immunity and converts cholesterol to 25-hydroxycholesterol (25HC). Previous studies have reported that CH25H and 25HC have an antiviral effect against multiple viruses. However, the interplay between SADS-CoV infection and CH25H or 25HC is still uncertain. Here, we found that CH25H and its enzymatic product 25HC restrained SADS-CoV replication by blocking membrane fusion. Our results show that CH25H was upregulated by SADS-CoV infection in vitro and in vivo, and that it was an IFN-stimulated gene in porcine ileum epithelial cells. Moreover, CH25H and CH25H mutants lacking catalytic activity can inhibit SADS-CoV replication. Furthermore, 25HC significantly suppressed SADS-CoV infection by inhibiting virus entry. Notably, we confirmed that CH25H and 25HC blocked SADS-CoV spike protein-mediated membrane fusion. Our data provide a possible antiviral therapy against SADS-CoV and other conceivable emerging coronaviruses in the future.