RESUMEN
Germinal centers (GCs) elicit protective humoral immunity through a combination of antibody-secreting cells and memory B cells, following pathogen invasion or vaccination. However, the possibility of a GC response inducing protective immunity against reinfection following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains unknown. We found GC activity was consistent with seroconversion observed in recovered macaques and humans. Rechallenge with a different clade of virus resulted in significant reduction in replicating virus titers in respiratory tracts in macaques with high GC activity. However, diffuse alveolar damage and increased fibrotic tissue were observed in lungs of reinfected macaques. Our study highlights the importance of GCs developed during natural SARS-CoV-2 infection in managing viral loads in subsequent infections. However, their ability to alleviate lung damage remains to be determined. These results may improve understanding of SARS-CoV-2-induced immune responses, resulting in better coronavirus disease 2019 (COVID-19) diagnosis, treatment, and vaccine development.
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COVID-19 , Centro Germinal , Inmunidad Humoral , Reinfección/inmunología , Animales , Anticuerpos Antivirales , COVID-19/inmunología , Humanos , Pulmón/patología , Pulmón/virología , Macaca , Células B de Memoria , SeroconversiónRESUMEN
Dengue virus (DV) is a mosquito-borne virus that is endemic to many tropical and subtropical areas. Recently, the annual incidence of DV infection has increased worldwide, including in Korea, due to global warming and increased global travel. We therefore sought to characterize the molecular and evolutionary features of DV-1 and DV-4 isolated from Korean overseas travelers. We used phylogenetic analysis based on the full coding region to classify isolates of DV-1 in Korea into genotype I (43251, KP406802), genotype IV (KP406803), and genotype V (KP406801). In addition, we found that strains of DV-4 belonged to genotype I (KP406806) and genotype II (43257). Evidence of positive selection in DV-1 strains was identified in the C, prM, NS2A, and NS5 proteins, whereas DV-4 showed positive selection only in the non-structural proteins NS2A, NS3, and NS5. The substitution rates per site per year were 5.58 × 10-4 and 6.72 × 10-4 for DV-1 and DV-4, respectively, and the time of the most recent common ancestor was determined using the Bayesian skyline coalescent method. In this study, the molecular, phylogenetic, and evolutionary characteristics of Korean DV-1 and DV-4 isolates were evaluated for the first time.
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Virus del Dengue/genética , Dengue/virología , Evolución Molecular , Viaje , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Secuencia de Bases , Dengue/epidemiología , Virus del Dengue/clasificación , Virus del Dengue/aislamiento & purificación , Genotipo , Humanos , Filogenia , ARN Viral/genética , República de Corea/epidemiología , Selección Genética , Serogrupo , Proteínas Virales/genéticaRESUMEN
PURPOSE: Deep sedation for endoscopic retrograde cholangiopancreatography (ERCP) can be challenging in elderly patients in the prone position. This study investigated the effect of a high flow nasal oxygen (HFNO) delivery system on oxygenation in this procedure compared with that of conventional nasal cannula oxygen administration. METHODS: A prospective randomized trial was conducted using HFNO and conventional nasal cannula in patients undergoing ERCP in the prone position. For each patient, the lowest oxygen saturation (SpO2), the incidence of hypoxemia defined as an SpO2 below 90%, and interruptions due to airway interventions were recorded during the procedure. RESULTS: The lowest mean (standard deviation) SpO2 recorded during the procedure was higher in the HFNO group than in the conventional control group [99.8 (0.6)% vs 95.1 (7.3)%; mean difference, 4.7%; 95% confidence interval, 2.3% to 7.1%; P Group x Time < 0.001]. While the lowest SpO2 during the procedure was lower than the baseline SpO2 in the control group, the lowest SpO2 during the procedure was higher than the baseline SpO2 in the HFNO group. Hypoxemia occurred only in the control group (n = 7; 19%; P = 0.01). Procedural interruptions, including discontinuation of sedation, patient stimulation, and jaw thrusting, occurred only in the control group (n = 9 [25%], n = 10 [28%], and n = 10 [28%] cases, respectively; P = 0.001 for each). CONCLUSION: In contrast to conventional nasal cannula, high flow nasal oxygen provided adequate oxygenation without causing procedural interruptions during ERCP, suggesting that HFNO may be used as a standard oxygen delivery method during these procedures. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT03872674); registered 11 March 2019.
RéSUMé: OBJECTIF: La sédation profonde pour cholangiopancréatographie rétrograde endoscopique (CPRE) peut être difficile à réaliser chez des patients âgés en position ventrale. Cette étude a exploré l'effet d'un système d'oxygénothérapie nasale à haut débit (ONHD) sur l'oxygénation pendant cette intervention par rapport à l'administration conventionnelle d'oxygène via une lunette nasale. MéTHODE: Une étude randomisée prospective a été réalisée en utilisant une ONHD ou une lunette nasale conventionnelle chez des patients subissant une CPRE en position ventrale. Pour chaque patient, la saturation en oxygène (SpO2) la plus basse, l'incidence d'hypoxémie définie en tant qu'une SpO2 inférieure à 90 %, et les interruptions provoquées par des interventions au niveau des voies aériennes ont été enregistrées au cours de l'intervention. RéSULTATS: La SpO2 moyenne (écart type) la plus basse enregistrée pendant l'intervention était plus élevée dans le groupe ONHD que dans le groupe témoin conventionnel [99,8 (0,6) % vs 95,1 (7,3) %; différence moyenne, 4,7%; intervalle de confiance 95 %, 2,3 % à 7,1 %; P Groupe x Temps < 0,001]. Alors que la SpO2 la plus basse pendant l'intervention était plus basse que la SpO2 de base dans le groupe témoin, la SpO2 la plus basse pendant l'intervention était plus élevée que la SpO2 de base dans le groupe ONHD. L'hypoxémie n'est survenue que dans le groupe témoin (n = 7; 19 %; P = 0,01). Il n'y a eu d'interruptions de l'intervention, y compris la cessation de la sédation, la stimulation du patient et le déplacement de la mâchoire inférieure vers l'avant, que dans le groupe témoin (n = 9 [25 %], n = 10 [28 %], et n = 10 [28 %] cas, respectivement; P = 0,001 pour chaque intervention). CONCLUSION: Comparativement à une lunette nasale conventionnelle, l'oxygénothérapie nasale à haut débit a procuré une oxygénation adéquate sans provoquer d'interruptions de l'intervention pendant une CPRE, suggérant que cette modalité pourrait être utilisée comme méthode standard d'oxygénothérapie pendant de telles interventions. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT03872674); enregistrée le 11 mars 2019.
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Cánula , Oxígeno , Anciano , Humanos , Hipoxia/terapia , Terapia por Inhalación de Oxígeno , Posición Prona , Estudios ProspectivosRESUMEN
Using a reliable primate model is critical for developing therapeutic advances to treat humans infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Here, we exposed macaques to high titers of SARS-CoV-2 via combined transmission routes. We observed acute interstitial pneumonia with endotheliitis in the lungs of all infected macaques. All macaques had a significant loss of total lymphocytes during infection, which were restored over time. These data show that SARS-CoV-2 causes a coronavirus disease 2019 (COVID-19)-like disease in macaques. This new model could investigate the interaction between SARS-CoV-2 and the immune system to test therapeutic strategies.
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Betacoronavirus/genética , Infecciones por Coronavirus/complicaciones , Modelos Animales de Enfermedad , Enfermedades Pulmonares Intersticiales/complicaciones , Linfopenia/complicaciones , Enfermedades de los Monos/virología , Neumonía Viral/complicaciones , Animales , COVID-19 , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/virología , Femenino , Enfermedades Pulmonares Intersticiales/patología , Linfopenia/patología , Macaca fascicularis , Macaca mulatta , Masculino , Enfermedades de los Monos/patología , Pandemias , Neumonía Viral/patología , Neumonía Viral/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2RESUMEN
Chronic inflammatory enteric diseases occur commonly in humans and animals, especially in captive bred macaques. However, information about the etiology of idiopathic chronic inflammatory diarrhea in cynomolgus monkeys is limited. In this paper, we reported the unusual case of idiopathic chronic diarrhea in a captive cynomolgus monkey based on microbial, imaging, and microbiome examinations.
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Diarrea/veterinaria , Disbiosis/veterinaria , Macaca fascicularis , Enfermedades de los Monos/etiología , Animales , Enfermedad Crónica/veterinaria , Diarrea/complicaciones , Diarrea/etiología , Diarrea/inmunología , Disbiosis/complicaciones , Disbiosis/etiología , Disbiosis/inmunología , Femenino , Enfermedades de los Monos/inmunologíaRESUMEN
In Korea, dengue infection has been frequently reported in travelers to tropical and subtropical countries. Global warming increases the probability of autochthonous dengue outbreaks in Korea. In this report, the molecular and evolutionary properties of four dengue virus (DENV) type 2 isolates from Korean overseas travelers were examined. Three of these isolates were classified as Cosmopolitan genotypes and further divided into sublineages 1 (43,253, 43,254) and 2 (43,248), while the other isolate (KBPV-VR29) was related to American genotypes. The variable amino acid motifs related to virulence and replication were identified in the structural and non-structural proteins. A negative selection mechanism was clearly verified in all of the DENV proteins. Potential recombination events were identified in the NS5 protein of the XSBN10 strain. The substitution rate (5.32 × 10-4 substitutions per site) and the time of the most recent common ancestor (TMRCA) for each evolutionary group were determined by the Bayesian skyline coalescent method. This study shows that DENV type 2 strains with distinct phylogenetic, evolutionary, and virulence characteristics have been introduced into Korea by overseas travelers and have the potential to trigger autochthonous dengue outbreaks.
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Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Sustitución de Aminoácidos/genética , Dengue/virología , Brotes de Enfermedades , Evolución Molecular , Genoma Viral/genética , Genotipo , Humanos , Filogenia , ARN Viral/genética , República de Corea , Serogrupo , Proteínas Virales/genética , Virulencia/genética , Replicación Viral/genéticaRESUMEN
BACKGROUND: Endoscopic submucosal dissection (ESD) has a favorable outcome, compared to esophagectomy, for early esophageal neoplasia. Recent studies used general anesthesia for esophageal ESD to minimize complications due to insufficient sedation and patient movement. We aimed to evaluate the safety of general anesthesia in comparison with conscious sedation provided by anesthesiologists for esophageal ESD. METHODS: We retrospectively reviewed the electronic medical records of 158 patients who underwent esophageal ESD under general anesthesia or conscious sedation provided by anesthesiologists. We evaluated the incidence of procedure-related complications, including perforation, post-ESD bleeding, cardiopulmonary adverse events (arrhythmia, hypotension, and hypoxemia), procedure failure, stricture, and new lung consolidation after ESD. Cases of frank perforation, post-ESD bleeding requiring a vigorous diagnostic approach, and cardiopulmonary adverse events were regarded as acute complications of ESD. RESULTS: Acute complications occurred only in the conscious sedation group (8/83 [9.6%] vs. 0/75 [0.0%]; p value = 0.007). The numbers of patients with frank perforation, post-ESD bleeding, and cardiopulmonary adverse events were four, one, and three, respectively. Moreover, new lung consolidation after ESD developed only in the conscious sedation group (7/83 [8.4%] vs. 0/75 [0.0%]; p value = 0.014). ESD failed in four patients in the conscious sedation group. The incidences of stricture that required stent insertion and hospital stay after ESD were comparable between the two groups. CONCLUSION: General anesthesia is associated with a lower incidence of acute procedure-related complications in esophageal ESD compared to conscious sedation provided by anesthesiologists. Therefore, we recommend general anesthesia as a safer option for esophageal ESD.
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Anestesia General/métodos , Sedación Consciente/métodos , Resección Endoscópica de la Mucosa/métodos , Neoplasias Esofágicas/cirugía , Complicaciones Intraoperatorias/etiología , Anciano , Anestesia General/efectos adversos , Sedación Consciente/efectos adversos , Resección Endoscópica de la Mucosa/efectos adversos , Neoplasias Esofágicas/patología , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Clostridium perfringens is ubiquitous in the environment and the gastrointestinal tract of warm-blooded animals. While part of the gut microbiome, abnormal growth of C. perfringens causes histotoxic, neurologic, and enteric diseases in a variety of animal species, including humans, due to the production of toxins. There is extremely limited information on C. perfringens infection in non-human primates. Presently, 10 strains were successfully isolated from 126 monkeys and confirmed by molecular and biochemical analyses. All isolates were genotype A based on molecular analysis. Alpha toxin was identified in all isolates. Beta 2 toxin was detected in only three isolates. No other toxins, including enterotoxin, beta, iota, epsilon, and net B toxin, were identified in any isolate. All isolates were highly susceptible to ß-lactam antibiotics. Double hemolysis and lecithinase activity were commonly observed in all strains. Biofilm formation, which can increase antibiotic resistance, was identified in 90% of the isolates. The data are the first report the prevalence and characteristics of C. perfringens isolated from captive cynomolgus monkeys.
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Toxinas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Clostridium perfringens/efectos de los fármacos , Clostridium perfringens/genética , Farmacorresistencia Bacteriana Múltiple , Macaca fascicularis/microbiología , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Infecciones por Clostridium/microbiología , Infecciones por Clostridium/veterinaria , Clostridium perfringens/aislamiento & purificación , ADN Bacteriano/genética , Heces/microbiología , Femenino , Genotipo , Masculino , Filogenia , Prevalencia , ARN Ribosómico 16S/genética , beta-Lactamas/farmacologíaRESUMEN
As agonists of TLR7/8, single-stranded RNAs (ssRNAs) are safe and promising adjuvants that do not cause off-target effects or innate immune overactivation. However, low stability prevents them from mounting sufficient immune responses. This study evaluates the adjuvant effects of ssRNA derived from the cricket paralysis virus intergenic region internal ribosome entry site, formulated as nanoparticles with a coordinative amphiphile, containing a zinc/dipicolylamine complex moiety as a coordinative phosphate binder, as a stabilizer for RNA-based adjuvants. The nanoformulated ssRNA adjuvant was resistant to enzymatic degradation in vitro and in vivo, and that with a coordinative amphiphile bearing an oleyl group (CA-O) was approximately 100â nm, promoted effective recognition, and improved activation of antigen-presenting cells, leading to better induction of neutralizing antibodies following single immunization. Hence, CA-O may increase the efficacy of ssRNA-based adjuvants, proving useful to meet the urgent need for vaccines during pathogen outbreaks.
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Adyuvantes Inmunológicos/farmacología , Células Presentadoras de Antígenos/inmunología , Composición de Medicamentos , Inmunidad Humoral/efectos de los fármacos , Nanotecnología , ARN/química , Adyuvantes Inmunológicos/química , Animales , HumanosRESUMEN
We describe the first case of biliary cirrhosis in Japanese macaque. Clinical signs had not been detected. The liver was nodular. Histopathologically, portal-to-portal pattern of fibrosis might have indicated chronic cholestasis. Fibrotic septa were infiltrated with inflammatory cells. Therefore, this case could be diagnosed as active incomplete biliary cirrhosis.
RESUMEN
BACKGROUND: Toxoplasma gondii (T. gondii) is an intracellular protozoan parasite that can infect warm-blooded animals including humans. New World monkeys, such as squirrel monkeys, are more susceptible to T. gondii than Old World monkeys, often developing fatal disease. METHODS: In this study, seven of thirteen dead squirrel monkeys at Seoul Grand Park were tested to find the cause of sudden death. RESULTS: The main histopathological findings included interstitial pneumonia, necrotizing hepatitis, and splenitis. Periodic acid-Schiff staining of liver, spleen, and lung revealed cyst structures consistent with bradyzoites. Amplification of the B1 gene was detected in the liver or spleen of all monkeys. Additionally, a restriction fragment length polymorphism assay and phylogenetic analysis of the GRA6 amplicon revealed a consistent clustering with the type II strain of T. gondii. CONCLUSIONS: This study is the first report of T. gondii infection of squirrel monkeys in Korea, and the first report of type II T. gondii based on GRA6 analysis in Korea.
RESUMEN
An evaluation of intestinal toxicity is important because the mucosal lining of the gastrointestinal tract is the first barrier for oral xenobiotics. Until now, a rat model has been recommended as the standard intestinal toxicity model and the Caco-2 cell line, originated from a human colon adenocarcinoma, has been used as an alternative to this model, but there are limitations regarding cost-effectiveness and the need for mimicry of the human system. In this study, we investigated whether zebrafish could be a valid alternative to rats and Caco-2 cells as an intestinal toxicity model. We focused on intestinal gene expression of cytochrome P450 3A65, oxidative stress, apoptosis, inflammation, and intestinal function. Reverse transcription-quantitative polymerase chain reaction analysis was conducted using three models: zebrafish, Sprague-Dawley rats and Caco-2 cells, and the transcript levels and patterns of indicator genes were analyzed in conjunction with histopathological changes. Our results suggested that representative intestinal toxicants, indomethacin, diclofenac and methotrexate, induced significant transcript level changes in marker genes such as CYP3A, inducible nitric oxide synthase, heme oxygenase 1, superoxide dismutase 1, glutathione peroxidase 1, BCL2 associated X, B-cell lymphoma 2, caspase 9, tumor protein p53, nuclear factor-κB, interleukin-1ß, tumor necrosis factor-alphaα and toll-like receptor 2 in the zebrafish model as in the rat and Caco-2 cells models. These results suggest that zebrafish model is sufficiently worth developing as an intestinal toxicity model that can replace or compensate the rat model or Caco-2 cell model.
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Alternativas a las Pruebas en Animales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología , Mucosa Intestinal/efectos de los fármacos , Pruebas de Toxicidad/métodos , Pez Cebra , Animales , Células CACO-2 , Diclofenaco/toxicidad , Humanos , Indometacina/toxicidad , Dosificación Letal Mediana , Metotrexato/toxicidad , Ratas Sprague-DawleyRESUMEN
BACKGROUND: Glutathione peroxidase 3 (GPx3) is involved in protecting cells from oxidative damage, and down-regulated levels of expression have been found in prostate cancer samples. We hypothesize that loss of the GPx3 increases the rate of prostate carcinogenesis and generated GPx3-deficient transgenic adenocarcinoma of the mouse prostate (TRAMP) mice. METHODS: Prostate cancer incidence and progression were determined in TRAMP, TRAMP/GPx3 (+/-) HET, and TRAMP/GPx3 (-/-) KO mice at 8, 16, and 20 weeks of age. RESULTS: We found that GPx3 expression was decreased in TRAMP mice and not detected in GPx3 KO mice both in mRNA and protein levels. Disruption of GPx3 expression in TRAMP mice increased the GU tract weights and the histopathological scores in each lobes with increased proliferation rates. Moreover, inactivation of one (+/-) or both (-/-) alleles of GPx3 resulted in increase in prostate cancer incidence with activated Wnt/ß-catenin pathway. CONCLUSIONS: Our results provide the first in vivo molecular genetic evidence that GPx3 does indeed function as a tumor suppressor during prostate carcinogenesis. Prostate 76:1387-1398, 2016. © 2016 Wiley Periodicals, Inc.
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Adenocarcinoma/metabolismo , Carcinogénesis/metabolismo , Glutatión Peroxidasa/biosíntesis , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Adenocarcinoma/genética , Animales , Carcinogénesis/genética , Modelos Animales de Enfermedad , Regulación hacia Abajo , Glutatión Peroxidasa/genética , Masculino , Ratones , Ratones Transgénicos , Estrés Oxidativo , Próstata/patología , Neoplasias de la Próstata/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genéticaRESUMEN
In order to examine the prevalence of Cryptosporidium infection in wild rodents and insectivores of South Korea and to assess their potential role as a source of human cryptosporidiosis, a total of 199 wild rodents and insectivore specimens were collected from 10 regions of South Korea and screened for Cryptosporidium infection over a period of 2 years (2012-2013). A nested-PCR amplification of Cryptosporidium oocyst wall protein (COWP) gene fragment revealed an overall prevalence of 34.2% (68/199). The sequence analysis of 18S rRNA gene locus of Cryptosporidium was performed from the fecal and cecum samples that tested positive by COWP amplification PCR. As a result, we identified 4 species/genotypes; chipmunk genotype I, cervine genotype I, C. muris, and a new genotype which is closely related to the bear genotype. The new genotype isolated from 12 Apodemus agrarius and 2 Apodemus chejuensis was not previously identified as known species or genotype, and therefore, it is supposed to be a novel genotype. In addition, the host spectrum of Cryptosporidium was extended to A. agrarius and Crosidura lasiura, which had not been reported before. In this study, we found that the Korean wild rodents and insectivores were infected with various Cryptosporidium spp. with large intra-genotypic variationa, indicating that they may function as potential reservoirs transmitting zoonotic Cryptosporidium to livestock and humans.
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Animales Salvajes/parasitología , Criptosporidiosis/parasitología , Cryptosporidium/genética , Cryptosporidium/aislamiento & purificación , Eulipotyphla/parasitología , Enfermedades de los Roedores/parasitología , Animales , Cryptosporidium/clasificación , Heces/parasitología , Genotipo , Datos de Secuencia Molecular , Murinae , Filogenia , República de CoreaRESUMEN
The transmission and pathogenesis of highly contagious fatal respiratory viruses are increasing, and the need for an on-site diagnostic platform has arisen as an issue worldwide. Furthermore, as the spread of respiratory viruses continues, different variants have become the dominant circulating strains. To prevent virus transmission, the development of highly sensitive and accurate on-site diagnostic assays is urgently needed. Herein, a facile diagnostic device is presented for multi-detection based on the results of detailed receptor-ligand dynamics simulations for the screening of various viral strains. The novel bioreceptor-treated electronics (receptonics) device consists of a multichannel graphene transistor and cell-entry receptors conjugated to N-heterocyclic carbene (NHC). An ultrasensitive multi-detection performance is achieved without the need for sample pretreatment, which will enable rapid diagnosis and prevent the spread of pathogens. This platform can be applied for the diagnosis of variants of concern in clinical respiratory virus samples and primate models. This multi-screening platform can be used to enhance surveillance and discriminate emerging virus variants before they become a severe threat to public health.
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Bioensayo , Grafito , Animales , Ligandos , ElectrónicaRESUMEN
Functional recovery after incomplete spinal cord injury depends on the effective rewiring of neuronal circuits. Here, we show that selective chemogenetic activation of either corticospinal projection neurons or intraspinal relay neurons alone led to anatomically restricted plasticity and little functional recovery. In contrast, coordinated stimulation of both supraspinal centers and spinal relay stations resulted in marked and circuit-specific enhancement of neuronal rewiring, shortened EMG latencies, and improved locomotor recovery.
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Regeneración Nerviosa , Traumatismos de la Médula Espinal , Humanos , Regeneración Nerviosa/fisiología , Plasticidad Neuronal , Traumatismos de la Médula Espinal/terapia , Neuronas/fisiología , Interneuronas , Recuperación de la Función/fisiología , Médula EspinalRESUMEN
SARS-CoV-2 receptor binding domains (RBDs) interact with both the ACE2 receptor and heparan sulfate on the surface of host cells to enhance SARS-CoV-2 infection. We show that suramin, a polysulfated synthetic drug, binds to the ACE2 receptor and heparan sulfate binding sites on the RBDs of wild-type, Delta, and Omicron variants. Specifically, heparan sulfate and suramin had enhanced preferential binding for Omicron RBD, and suramin is most potent against the live SARS-CoV-2 Omicron variant (B.1.1.529) when compared to wild type and Delta (B.1.617.2) variants in vitro. These results suggest that inhibition of live virus infection occurs through dual SARS-CoV-2 targets of S-protein binding and previously reported RNA-dependent RNA polymerase inhibition and offers the possibility for this and other polysulfated molecules to be used as potential therapeutic and prophylactic options against COVID-19.
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COVID-19 , SARS-CoV-2 , Humanos , Suramina/farmacología , Enzima Convertidora de Angiotensina 2 , Glicoproteína de la Espiga del Coronavirus , Heparitina SulfatoRESUMEN
Severe fever with thrombocytopenia syndrome virus was first discovered in 2009 as the causative agent of severe fever with thrombocytopenia syndrome. Despite its potential threat to public health, no prophylactic vaccine is yet available. This study developed a heterologous prime-boost strategy comprising priming with recombinant replication-deficient human adenovirus type 5 (rAd5) expressing the surface glycoprotein, Gn, and boosting with Gn protein. This vaccination regimen induced balanced Th1/Th2 immune responses and resulted in potent humoral and T cell-mediated responses in mice. It elicited high neutralizing antibody titers in both mice and non-human primates. Transcriptome analysis revealed that rAd5 and Gn proteins induced adaptive and innate immune pathways, respectively. This study provides immunological and mechanistic insight into this heterologous regimen and paves the way for future strategies against emerging infectious diseases.
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Adenovirus Humanos , Síndrome de Trombocitopenia Febril Grave , Vacunas Virales , Animales , Ratones , Vacunas Virales/genética , Vacunación/métodos , Linfocitos T , Vectores Genéticos/genética , Anticuerpos Antivirales , Inmunización Secundaria/métodosRESUMEN
Dengue viruses (DENVs) exploit monocytes and macrophages for tropism and replication, therefore, establishing a long-term reservoir. However, their roles in dengue pathogenesis remains unclear. Here, using the human monocytic cell line THP-1, human primary monocytes, and non-human primate models, we show that DENV-infected monocytes represent suitable carriers for circulatory viral dissemination. Monocyte-derived macrophages expressing M2 surface markers at the gene level efficiently replicated, while the productivity of monocyte replication was low. However, attachment of DENVs to the cellular surface of monocytes was similar to that of macrophages. Furthermore, after differentiation with type-2 cytokines, DENV-attached monocytes could replicate DENVs. Productive DENV infection was confirmed by intravenous injection of DENVs into nonhuman primate model, in which, DENV attachment to monocytes was positively correlated with viremia. These results provide insight into the role of circulating monocytes in DENV infection, suggesting that monocytes directly assist in DENV dissemination and replication during viremia and could be applied to design antiviral intervention.