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1.
Arch Orthop Trauma Surg ; 142(10): 2585-2596, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34089372

RESUMEN

INTRODUCTION: Traditionally, partially threaded cancellous lag screws (PTCS) are used for most medial malleolar fractures but are often challenging to execute in elderly patients because of the high risk of postoperative complications. Limited literature explores whether hook-type locking compression plates (LCPs) reliably offer better outcomes than PTCS in elderly patients. We aimed to compare the midterm radiologic and clinical outcomes between hook-type LCP and PTCS for medial malleolar fractures in an elderly population. METHODS: We included 258 patients, aged 65 years and above, treated with either a hook-type locking plate (hook LCP group: 121 patients) or PTCS (screw group: 137 patients), and with follow-ups of at least 36 months in this retrospective study. Radiographic assessments included the union rate and interval to fracture union. Clinical assessment included the postoperative complications and revision procedures. RESULTS: Although a significantly higher rate of comminuted fractures was observed in the hook LCP group than in the screw group (p < .001), no significant difference in the union rate was observed between the two groups (hook LCP group: 93.4% vs. screw group: 89.8%, p = .151), and a significantly shorter interval to union was observed in the hook LCP group (10.2 ± 7.0 vs. 12.3 ± 6.7 weeks, p = .015). There was a trend toward a lower rate of complications, including revision procedures, in the hook LCP group than in the screw group (19.9% vs. 28.5%, p = .107 and 6.6% vs. 13.8%, p = .074). CONCLUSION: Hook-type LCP may be an alternative option for treating medial malleolar fractures with comminution in elderly patients.


Asunto(s)
Fracturas de Tobillo , Fijación Interna de Fracturas , Anciano , Fracturas de Tobillo/cirugía , Fenómenos Biomecánicos , Placas Óseas , Tornillos Óseos , Fijación Interna de Fracturas/métodos , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
2.
Entropy (Basel) ; 22(5)2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33286326

RESUMEN

Despite the potential benefits of reducing system costs and improving spectral efficiency, it is challenging to implement cloud radio access network (C-RAN) systems due to the performance degradation caused by finite-capacity fronthaul links and inter-cluster interference signals. This work studies inter-cluster cooperative reception for the uplink of a two-cluster C-RAN system, where two nearby clusters interfere with each other on the uplink access channel. The radio units (RUs) of two clusters forward quantized and compressed version of the uplink received signals to the serving baseband processing units (BBUs) via finite-capacity fronthaul links. The BBUs of the clusters exchange the received fronthaul signals via finite-capacity backhaul links with the purpose of mitigating inter-cluster interference signals. Optimization of conventional cooperation scheme, in which each RU produces a single quantized signal, requires an exhaustive discrete search of exponentially increasing search size with respect to the number of RUs. To resolve this issue, we propose an improved inter-BBU, or inter-cluster, cooperation strategy based on layered compression, where each RU produces two descriptions, of which only one description is forwarded to the neighboring BBU on the backhaul links. We discuss the optimization of the proposed inter-cluster cooperation scheme, and validate the performance gains of the proposed scheme via numerical results.

3.
Biosci Biotechnol Biochem ; 81(7): 1356-1362, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28351214

RESUMEN

It has been shown that extremely low-frequency electromagnetic fields (ELFMF) affect regulation of cell fate and differentiation. Thus, the aim of this study was to investigate the role of ELFMFs in the enhancement of astrocytic differentiation. ELFMF exposure reduced the rate of proliferation and enhanced astrocytic differentiation. The ELFMF-treated cells showed increased levels of the astrocyte marker (GFAP), while those of the early neuronal marker (Nestin) and stemness marker (OCT3/4) were downregulated. The reactive oxygen species (ROS) level was observed to be significantly elevated after ELFMF exposure, which strengthens the modulatory role of SIRT1 and SIRT1 downstream molecules (TLE1, HES1, and MASH1) during astrocytic differentiation. After nicotinamide (5 mM) mediated inhibition of SIRT1, levels of TLE1, HES1, and MASH1 were examined; TLE1 was significantly upregulated and MASH1 was downregulated. These results suggest that ELFMFs induce astrocytic differentiation through activation of SIRT1 and SIRT1 downstream molecules.


Asunto(s)
Astrocitos/metabolismo , Células de la Médula Ósea/metabolismo , Campos Electromagnéticos , Células Madre Mesenquimatosas/metabolismo , Sirtuina 1/genética , Astrocitos/citología , Astrocitos/efectos de los fármacos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Diferenciación Celular , Línea Celular , Proliferación Celular , Proteínas Co-Represoras , Regulación de la Expresión Génica , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Nestina/genética , Nestina/metabolismo , Neurogénesis/genética , Niacinamida/farmacología , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transducción de Señal , Sirtuina 1/antagonistas & inhibidores , Sirtuina 1/metabolismo , Factor de Transcripción HES-1/genética , Factor de Transcripción HES-1/metabolismo
4.
BMC Complement Altern Med ; 17(1): 147, 2017 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-28274225

RESUMEN

BACKGROUND: Fainting is one of the major adverse events that can occur as a result of acupuncture treatment. However, the observation of changes in biological parameters is rarely available when fainting occurs. In this case report, we could observe changes in the electroencephalogram (EEG) in a participant who fainted while participating in a clinical trial aiming to observe a relationship between acupuncture stimulation at LI4 acupuncture point and EEG in healthy adults. CASE PRESENTATION: The EEG pattern of participant changed twice. The first change was in response to the acupuncture needle insertion, and the second change occurred during fainting. Both changes consisted of a burst in EEG amplitude, but the pattern of details was different. Multiple areas of the cortex were activated, and the increased ratio of the γ wave was not observed during fainting. While acupuncture needle insertion, only the sensory cortex were activated and increased the ratio of the γ wave. CONCLUSIONS: This single case is presented to improve the understanding of fainting during acupuncture as an adverse event and to explore the mechanism of acupuncture treatment, despite the absence of statistics and repeatability. This information can provide a new viewpoint about the mechanism of acupuncture treatment and the possibility of new techniques based on acupuncture.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura/efectos adversos , Síncope , Adulto , Electroencefalografía , Femenino , Humanos , Adulto Joven
5.
J Foot Ankle Surg ; 56(4): 713-717, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28479162

RESUMEN

The aim of the present study was to evaluate and compare the clinical and radiologic results of internal fixation with a headless cannulated screw versus a locking compression distal ulna hook plate for fractures at the base of the fifth metatarsal bone, zone 1. From April 2012 to April 2015, 30 cases (29 patients) were retrospectively evaluated. The mean follow-up period was 13 months. The patients were divided into 2 groups stratified by the fixation method: screw (group A, n = 15) or plate (group B, n = 15). We measured the displacement to diastasis of the fracture on the foot oblique radiographs taken pre- and postoperatively in each group, recorded the time to bony union, and measured the difference in the reduction distance in each group. The clinical results were evaluated using the American Orthopaedic Foot and Ankle Society midfoot score at 12 months postoperatively. In group A, the mean interval to union was 54.2 ± 9.3 days, the mean displacement to diastasis had improved to 0.3 ± 0.4 mm postoperatively (p < .001), and the mean reduction distance was 2.9 ± 1.0 mm postoperatively. In group B, the mean interval to union was 41.5 ± 7.0 days, the mean displacement to diastasis had improved to 0.06 ± 0.2 mm postoperatively (p < .001), and the mean reduction distance was 4.1 ± 1.6 mm. The American Orthopaedic Foot and Ankle Society midfoot scale score was 97.7 ± 3.4 in group A and 98.2 ± 3.2 in group B. The interval to union was significantly different between the 2 groups (p = .01). No complications were recorded. Our findings have shown that the plate is a reasonable and alternative method for the surgical treatment of fifth metatarsal base fractures.


Asunto(s)
Placas Óseas , Tornillos Óseos , Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/cirugía , Huesos Metatarsianos/lesiones , Adulto , Anciano , Femenino , Curación de Fractura , Fracturas Óseas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
6.
Foot Ankle Surg ; 22(4): e25-e28, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27810034

RESUMEN

Synovial chondromatosis developes by metaplasia of the synovial cells in the synovium of joints, and is a benign synovial tumor with multiple cartilaginous nodules. It is most commonly found in single and large joints, such as the knee, hip, and shoulder. Occurrence in the foot and ankle is uncommon, although there have been previous reports in the orthopedic and radiological literature of primary synovial chondromatosis in the subtalr, calcaneocuboid, naviculocuneiform, and metatarsaophalangeal joints. To our knowledge, occurrence in the talonavicular joint is even rarer, with only one report in the literature to date. Here, we report a case of synovial chondromatosis of the talonavicular joint, alongside a review of the literature.


Asunto(s)
Condromatosis Sinovial/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Procedimientos Ortopédicos/métodos , Articulaciones Tarsianas/diagnóstico por imagen , Artralgia/diagnóstico , Artralgia/etiología , Biopsia con Aguja , Condromatosis Sinovial/patología , Condromatosis Sinovial/cirugía , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Dimensión del Dolor , Enfermedades Raras , Índice de Severidad de la Enfermedad , Articulaciones Tarsianas/patología , Articulaciones Tarsianas/cirugía , Resultado del Tratamiento
7.
Biosens Bioelectron ; 232: 115316, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37079990

RESUMEN

Digital enzyme linked immunosorbent assays (ELISA) can be used to detect various antigens such as spike (S) or nucleocapsid (N) proteins of SARS-CoV-2, with much higher sensitivity compared to that achievable using conventional antigen tests. However, the use of microbeads and oil for compartmentalization in these assays limits their user-friendliness and causes loss of assay information due to the loss of beads during the process. To improve the sensitivity of antigen test, here, we developed an oil- and bead-free single molecule counting assay, with rolling circle amplification (RCA) on a substrate. With RCA, the signal is localized at the captured region of an antigen, and the signal from a single antigen molecule can be visualized using the same immune-reaction procedures as in the conventional ELISA. Substrate-based single molecule assay was theoretically evaluated for kd value, and the concentration of capture and detection antibodies. As a feasibility test, biotin-conjugated primer and mouse IgG conjugates were detected even at femto-molar concentrations with this digital immuno-RCA. Using this method, we detected the N protein of SARS-CoV-2 with a limit of detection less than 1 pg/mL more than 100-fold improvement compared to the detection using conventional ELISA. Furthermore, testing of saliva samples from COVID-19 patients and healthy controls (n = 50) indicated the applicability of the proposed method for detection of SARS-CoV-2 with 99.5% specificity and 90.9% sensitivity.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Animales , Ratones , SARS-CoV-2 , COVID-19/diagnóstico , Saliva , Ensayo de Inmunoadsorción Enzimática/métodos , Antígenos , Sensibilidad y Especificidad , Anticuerpos Antivirales
8.
Front Vet Sci ; 10: 1207289, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37546334

RESUMEN

High pathogenicity avian influenza (HPAI) is a viral disease with devastating consequences for the poultry industry worldwide. Domestic ducks are a major source of HPAI viruses in many Eurasian countries. The infectivity and pathogenicity of HPAI viruses in ducks vary depending on host and viral factors. To assess the factors influencing the infectivity and pathogenicity of HPAI viruses in ducks, we compared the pathobiology of two HPAI viruses (H5N1 clade 2.3.2.1c and H5N6 clade 2.3.4.4e) in 5- and 25-week-old ducks. Both HPAI viruses caused mortality in a dose-dependent manner (104, 106, and 108 EID50) in young ducks. By contrast, adult ducks were infected but exhibited no mortality due to either virus. Viral excretion was higher in young ducks than in adults, regardless of the HPAI strain. These findings demonstrate the age-dependent mortality of clade 2.3.2.1c and clade 2.3.4.4e H5 HPAI viruses in ducks.

9.
Anim Biosci ; 35(4): 631-637, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34696574

RESUMEN

OBJECTIVE: Surface disinfection is important in the proper running of livestock farms. However, disinfection of farm equipment and facilities is difficult because they are made of different materials, besides having large surface areas and complex structures. 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (Si-QAC) is a quaternary ammonium salt-based disinfectant that attaches to various surfaces by forming covalent bonds and maintains its disinfecting capacity for a considerable time. Our aim was to evaluate the potential use of Si-QAC for disinfection of farm equipment and facilities. METHODS: The short- and long-term antimicrobial and antiviral effects of Si-QAC were evaluated in both laboratory and farm settings using modified quantitative assessment method based on the standard operating procedures of the United States Environmental Protection Agency. RESULTS: Si-QAC was highly effective in controlling the growth of the Newcastle disease virus and avian pathogenic Escherichia coli. Electron microscopy revealed that the mechanism underlying the disinfection activity of Si-QAC was associated with its ability to damage the outer membrane of the pathogen cells. In the field test, Si-QAC effectively reduced viral contamination of surfaces of equipment and space. CONCLUSION: Our results suggest that Si-QAC has great potential as an effective chemical for disinfecting farm equipment and facilities. This disinfectant could retain its disinfection ability longer than other commercial disinfectants and contribute to better farm biosecurity.

10.
Front Vet Sci ; 8: 616755, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34113668

RESUMEN

Highly pathogenic avian influenza (HPAI) is considered as one of the most devastating poultry diseases. It is imperative to immediately report any known outbreaks to the World Organization for Animal Health. Early detection of infected birds is of paramount importance to control virus spread, thus minimizing the associated economic loss. In this study, thermal imaging camera devices were used to detect change in the maximum surface temperature (MST) of chickens (n = 5) and ducks (n = 2) as an early indicator of experimental HPAI infection. The MST of both chickens and ducks increased at least 24 h before the manifestation of clinical signs of HPAI infection, depending on the severity of the infection. The basal MST was recorded for broiler chickens housed under small pen and normal farm conditions without intentional infection. A threshold cutoff of MST was established based on the circadian rhythm of normal MST. This study suggests that thermal imaging of chickens and ducks is a promising tool to screen any potential HPAI-infected flock in order to expedite HPAI diagnosis.

11.
Biosens Bioelectron ; 192: 113504, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34298498

RESUMEN

Although urinary exosomal microRNAs (miRNAs) have recently emerged as potential biomarkers, clinical applications are still limited due to their low concentration in small volumes of clinical samples. Therefore, the development of a non-invasive, specific diagnostic tool, along with profiling exosomal miRNA markers from urine, remains a significant challenge. Here, we present hydrogel-based hybridization chain reaction (HCR) for multiplex signal amplification to detect urinary exosomal miRNAs from human clinical samples. We succeeded in identifying small amounts (~amol) of exosomal miRNAs from 600 µL of urine with up to ~35-fold amplification and enhanced detection limits by over an order of magnitude for two miRNA biomarker candidates, hsa-miR-6090 and hsa-miR-3665. Furthermore, we proposed ratiometric analysis without requiring normalization to a reference miRNA and validated the clinical diagnostic potential toward differentiating prostate cancer patients from healthy controls. Our hydrogel-based HCR could serve as a new diagnostic platform for a non-invasive liquid biopsy before burdensome tissue biopsy of various diseases, including prostate cancer screening, complementing the PSA test.


Asunto(s)
Técnicas Biosensibles , Exosomas , MicroARNs , Neoplasias de la Próstata , Biomarcadores de Tumor/genética , Detección Precoz del Cáncer , Exosomas/genética , Humanos , Hidrogeles , Masculino , MicroARNs/genética , Antígeno Prostático Específico , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética
12.
Viruses ; 13(8)2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34452517

RESUMEN

Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019, suffer from respiratory and non-respiratory symptoms. Among these symptoms, the loss of smell has attracted considerable attention. The objectives of this study were to determine which cells are infected, what happens in the olfactory system after viral infection, and how these pathologic changes contribute to olfactory loss. For this purpose, Syrian golden hamsters were used. First, we verified the olfactory structures in the nasal cavity of Syrian golden hamsters, namely the main olfactory epithelium, the vomeronasal organ, and their cellular components. Second, we found angiotensin-converting enzyme 2 expression, a receptor protein of SARS-CoV-2, in both structures and infections of supporting, microvillar, and solitary chemosensory cells. Third, we observed pathological changes in the infected epithelium, including reduced thickness of the mucus layer, detached epithelia, indistinct layers of epithelia, infiltration of inflammatory cells, and apoptotic cells in the overall layers. We concluded that a structurally and functionally altered microenvironment influences olfactory function. We observed the regeneration of the damaged epithelium, and found multilayers of basal cells, indicating that they were activated and proliferating to reconstitute the injured epithelium.


Asunto(s)
COVID-19/virología , Células Quimiorreceptoras/virología , Mucosa Olfatoria/virología , SARS-CoV-2 , Órgano Vomeronasal/virología , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , COVID-19/patología , Células Quimiorreceptoras/patología , Masculino , Mesocricetus , Cavidad Nasal/patología , Cavidad Nasal/virología , Mucosa Olfatoria/metabolismo , Mucosa Olfatoria/patología , Neuronas Receptoras Olfatorias/metabolismo , Neuronas Receptoras Olfatorias/patología , Neuronas Receptoras Olfatorias/virología , Receptores de Coronavirus/metabolismo , Regeneración , SARS-CoV-2/aislamiento & purificación , Órgano Vomeronasal/metabolismo , Órgano Vomeronasal/patología
13.
J Virol Methods ; 292: 114126, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33711374

RESUMEN

Highly pathogenic avian influenza viruses (HPAIVs) and low pathogenic avian influenza viruses (LPAIVs) represent important threats to the poultry industry and global human health. Due to the high rates of avian influenza virus (AIV) transmission, controlling AIV outbreaks is challenging. HPAIV is known to be transmitted from wild birds to domestic ducks, from which it can be transmitted to layer and broiler chickens. Therefore, surveillance of AIV in domestic ducks and chickens in advance of outbreaks can prevent its spread and enable timely implementation of disease control measures. Certain molecular diagnostic tools can be applied in the field for faster AIV detection. In this study, we evaluated the AIV-detection ability of two insulated isothermal PCR (iiPCR) devices, POCKIT™Micro DUO Nucleic Acid Analyzer (POCKIT DUO) and POCKIT™ Central Nucleic Acid Analyzer (POCKIT Central). We found that the analytical, in vivo and clinical performances of the two POCKIT devices were comparable to those of real-time reverse transcription PCR. Due to their brief protocols and short detection times, POCKIT DUO and POCKIT Central represent promising molecular diagnostic devices for the reliable detection of AIV.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Animales , Pollos , Humanos , Virus de la Influenza A/genética , Gripe Aviar/diagnóstico , Aves de Corral , Reacción en Cadena en Tiempo Real de la Polimerasa
14.
Acta Ortop Bras ; 28(2): 55-59, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32425664

RESUMEN

OBJECTIVE: To compare clinical and radiologic results and complications of patients who underwent arthrodesis using a transfibular approach with either a cannulated screw or an anterior fusion plate. METHODS: Patients who underwent ankle arthrodesis were divided into two groups according to the used materials: 6.5 mm cannulated screw (A) and anterior fusion plate (B). The clinical scores were compared between groups. The radiologic results were then assessed by union time. The results were statistically analyzed using SPSS 20. RESULTS: There was no significant difference between both groups in the American Orthopedic Foot & Ankle Society (AOFAS) score (p = 0.75), and in the visual analog scale (p = 0.42). In group B, two cases included wound infection at the surgical site. In tt A, the mean union time was 10.5 ± 2.3 weeks. In group B, it was 7.8 ± 1.3. There was a statistically significant difference (p = 0.007) between union time in both groups. CONCLUSION: Anterior fusion plate is an effective method for shorter union time, but the surgeon should be careful with the surgical wound at the skin incision site in the lesion of the distal tibia. Level of Evidence III, Retrospective comparative study.


OBJETIVO: Comparar os resultados clínicos e radiológicos assim como as complicações de pacientes sujeitos a artrodese de abordagem transfibular com o uso de parafuso canulado ou placa óssea anterior. MÉTODOS: Pacientes sujeitos a artrodese do tornozelo foram divididos em dois grupos de acordo com os materiais usados: parafuso canulado de 6,5 mm (A) e placa óssea anterior (B). Os escores clínicos de ambos os grupos foram comparados e os resultados radiológicos foram avaliados de acordo com o tempo de união óssea. Os resultados foram analisados estatisticamente usando SPSS 20. RESULTADOS: Não houve diferença significativa entre os grupos quanto ao escore American Orthopedic Foot & Ankle Society (AOFAS) (p = 0,75) e a escala visual analógica (p = 0,42). No grupo B, ocorreu infecção na área da cirurgia em dois casos. No grupo A, a média de tempo de união foi de 10,5 ± 2,3 semanas. No grupo B, este foi de 7,8 ± 1,3. Constatou-se diferença estatisticamente significante (p = 0,007) quanto ao tempo de união em ambos os grupos. CONCLUSÃO: Os autores concluíram que a placa óssea anterior é um método eficiente para tempos de união curtos, porém o cirurgião deve ficar atento à ferida cirúrgica na área de incisão da pele em casos de lesão na tíbia distal. Nível de Evidência III, Estudo retrospectivo comparativo.

15.
Clin Exp Vaccine Res ; 9(2): 174-178, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32864375

RESUMEN

Currently, no vaccine or established therapeutic agents are available for coronavirus disease 2019. The sharp increase in demand for personal protective equipment (PPE) necessitates an improvement in the protective efficacy of PPE. We evaluated the potential antimicrobial and antiviral effects of a surface-coating disinfectant (3-(trimethoxysilyl)propyldimethyl octadecyl ammonium chloride, Si-QAC) when applied onto PPE. Si-QAC-pre-coated PPE was artificially contaminated with either influenza virus or Salmonella. The results showed significantly reduced influenza and Salmonella titers in Si-QAC-coated PPE; these antimicrobial effects lasted 7 days. This suggests that this surface-coating disinfectant effectively reduces pathogen contamination of PPE, enabling their safe and long-term use.

16.
Vaccines (Basel) ; 8(4)2020 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-33419331

RESUMEN

Clade 2.3.4.4c H5N6 avian influenza A viruses (AIVs) may have originally adapted to infect chickens and have caused highly pathogenic avian influenza (HPAI) in poultry and human fatalities. Although A/Puerto Rico/8/1934 (H1N1) (PR8)-derived recombinant clade 2.3.4.4c H5N6 vaccine strains have been effective in embryonated chicken eggs-based vaccine production system, they need to be improved in terms of immunogenicity and potential mammalian pathogenicity. We replaced the PB2 gene alone or the PB2 (polymerase basic protein 2), NP (nucleoprotein), M (matrix protein) and NS (non-structural protein) genes together in the PR8 strain with corresponding genes from AIVs with low pathogenicity to remove mammalian pathogenicity and to match CD8+ T cell epitopes with contemporary HPAI viruses, respectively, without loss of viral fitness. Additionally, we tested the effect of the H103Y mutation of hemagglutinin (HA) on antigen productivity, mammalian pathogenicity and heat/acid stability. The replacement of PB2 genes and the H103Y mutation reduced the mammalian pathogenicity but increased the antigen productivity of the recombinant vaccine strains. The H103Y mutation increased heat stability but unexpectedly decreased acid stability, probably resulting in increased activation pH for HA. Interestingly, vaccination with inactivated recombinant virus with replaced NP, M and NS genes halted challenge virus shedding earlier than the recombinant vaccine without internal genes replacement. In conclusion, we successfully generated recombinant clade 2.3.4.4c H5N6 vaccine strains that were less pathogenic to mammals and more productive and heat stable than conventional PR8-derived recombinant strains by optimization of internal genes and the H103Y mutation of HA.

17.
Vaccine ; 37(42): 6154-6161, 2019 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-31495597

RESUMEN

The clade 2·3·4·4 H5Nx is a highly pathogenic avian influenza (HPAI) virus, which first appeared in China and has spread worldwide since then, including Korea. It is divided into subclades a - d, but the PR8-derived recombinant clade 2·3·4·4 a viruses replicate inefficiently in embryonated chicken eggs (ECEs). High virus titer in ECEs and no mammalian pathogenicity are the most important prerequisites of efficacious and safer vaccine strains against HPAI. In this study, we have synthesized hemagglutinin (HA) and neuraminidase (NA) genes based on the consensus amino acid sequences of the clade 2·3·4·4a and b H5N8 HPAIVs, using the GISAID database. We generated PR8-derived H5N8 recombinant viruses with single point mutations in HA and NA, which are related to efficient replication in ECEs. The H103Y mutation in HA increased mammalian pathogenicity as well as virus titer in ECEs, by 10-fold. We also successfully eradicated mammalian pathogenicity in H103Y-bearing H5N8 recombinant virus by exchanging PB2 genes of PR8 and 01310 (Korean H9N2 vaccine strain). The final optimized H5N8 vaccine strain completely protected against a heterologous clade 2·3·4·4c H5N6 HPAIV in chickens, and induced hemagglutination inhibition (HI) antibody in ducks. However, the antibody titer of ducks showed age-dependent results. Thus, H103Y and 01310PB2 gene have been successfully applied to generate a highly productive, safe, and efficacious clade 2·3·4·4 H5N8 vaccine strain in ECEs.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Subtipo H5N8 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Aviar/prevención & control , Neuraminidasa/inmunología , Vacunas Sintéticas/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antivirales/sangre , Bioingeniería , Embrión de Pollo , Pollos/inmunología , Patos/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Vacunas contra la Influenza/genética , Gripe Aviar/inmunología , Gripe Aviar/virología , Neuraminidasa/genética , Mutación Puntual/genética
18.
Integr Med Res ; 7(3): 231-237, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30271711

RESUMEN

BACKGROUND: Deqi is a term describing a special state of the human body, which is ready to cure itself through acupuncture stimulation and is believed to be a key factor in acupuncture treatment. However, knowledge about deqi remains subjective. Therefore, in this study, we aimed to determine the factors related to deqi generation based on present studies to promote the progression of deqi research. METHODS: A term frequency-inverse document frequency (Tf-idf) was used to extract key elements from the abstracts of 148 articles searched from Pubmed, and the network structure between key elements was analyzed. RESULTS: A total of 37 items were extracted from the abstracts. Each item was categorized into one of three groups (acupuncture-related sensation, interventions or organ/mechanism). Acupuncture-related sensation was studied by comparing the items in the interventions group with the organ/mechanism group. Key elements related to deqi generation included muscles from the organ/mechanism group and intensity, depth and pressure from the interventions group. Items that belonged to the acupuncture-related sensation group were divided into two clusters: one cluster consisted of pain, tingling, aching, soreness, heaviness, fullness and numbness; the other included warm, cold and dull. CONCLUSION: We could find out that the trend of deqi was leaning towards the interventions group, which related to the generation of deqi; thus, authors concluded that the mechanism studies, which are aimed to investigate why deqi is generated or what kind of meanings it has, are needed for evolution of acupuncture theory and application of the brand new technologies and related devices.

20.
Infect Genet Evol ; 61: 127-133, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29601871

RESUMEN

In recent years, avian paramyxovirus type 4 (APMV-4) frequently isolated from wild and domestic bird populations particularly waterfowls worldwide. However, molecular characteristics and genetic diversity of APMV-4 are uncertain, owing to the limited availability of sequence information. A total of 11 APMV-4 strains from 9850 fecal, swab, and environmental samples were isolated during the surveillance program in wintering seasons of 2013-2017 in South Korea. We performed genetic characterization and phylogenetic analysis to investigate the genetic diversity and relatedness between isolates from the region. We report high APMV-4 genetic diversity (multiple genotypes and sub-genotypes) among wild bird and poultry populations in Korea and that the potential virus exchange occurs between neighboring countries via wild bird migration. Furthermore, our study results suggest the possibility of transcontinental transmission of APMV-4 between Asia and Europe.


Asunto(s)
Infecciones por Avulavirus/virología , Avulavirus/genética , Aves/virología , Animales , Animales Salvajes/virología , Avulavirus/clasificación , Infecciones por Avulavirus/veterinaria , Código de Barras del ADN Taxonómico , Variación Genética/genética , Filogenia , República de Corea
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