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1.
Drug Dev Res ; 83(7): 1623-1640, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35989498

RESUMEN

The global emergence of coronavirus disease 2019 (COVID-19) has caused substantial human casualties. Clinical manifestations of this disease vary from asymptomatic to lethal, and the symptomatic form can be associated with cytokine storm and hyperinflammation. In face of the urgent demand for effective drugs to treat COVID-19, we have searched for candidate compounds using in silico approach followed by experimental validation. Here we identified celastrol, a pentacyclic triterpene isolated from Tripterygium wilfordii Hook F, as one of the best compounds out of 39 drug candidates. Celastrol reverted the gene expression signature from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected cells and irreversibly inhibited the recombinant forms of the viral and human cysteine proteases involved in virus invasion, such as Mpro (main protease), PLpro (papain-like protease), and recombinant human cathepsin L. Celastrol suppressed SARS-CoV-2 replication in human and monkey cell lines and decreased interleukin-6 (IL-6) secretion in the SARS-CoV-2-infected human cell line. Celastrol acted in a concentration-dependent manner, with undetectable signs of cytotoxicity, and inhibited in vitro replication of the parental and SARS-CoV-2 variant. Therefore, celastrol is a promising lead compound to develop new drug candidates to face COVID-19 due to its ability to suppress SARS-CoV-2 replication and IL-6 production in infected cells.


Asunto(s)
Antivirales , Tratamiento Farmacológico de COVID-19 , Proteasas 3C de Coronavirus , Triterpenos Pentacíclicos , Humanos , Antivirales/farmacología , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Interleucina-6 , Simulación del Acoplamiento Molecular , Triterpenos Pentacíclicos/farmacología , Inhibidores de Proteasas/farmacología , SARS-CoV-2/efectos de los fármacos , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo
2.
J Med Virol ; 93(11): 6132-6139, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34050944

RESUMEN

Cholesteatomas are frequent middle ear benign tumors of unknown etiology. Infectious agents have been considered as possible contributing factors in the pathogenesis of cholesteatomas. Aiming to investigate the presence of respiratory viruses in primary cholesteatoma tissues, 26 formalin-fixed paraffin-embedded primary cholesteatoma tissues obtained from patients seen at the of the Clinical Hospital of the University of São Paulo School of Medicine, in Ribeirão Preto, Brazil were tested by real-time polymerase chain reaction (PCR). Considering the PCR results, 35% of the tissues were positive for human rhinovirus (HRV), 15.3% for human enterovirus (EV), 3.8% for human metapneumovirus (HMPV), and 3.8% for human bocavirus (HBoV). Serial immunohistochemistry for virus antigens and cell surface markers evidenced that the viruses were associated with fibroblasts, dendritic cells, macrophages, B lymphocytes, CD4+ , and CD8+ T lymphocytes. These findings indicate for the first time the presence of active respiratory virus infection in primary cholesteatoma tissues, suggesting that persisting virus infection in the middle could play a role in the pathogenesis and evolution of cholesteatomas.


Asunto(s)
Colesteatoma/virología , Enterovirus/aislamiento & purificación , Bocavirus Humano/aislamiento & purificación , Metapneumovirus/aislamiento & purificación , Rhinovirus/aislamiento & purificación , Adolescente , Adulto , Anciano , Brasil , Colesteatoma/patología , Estudios Transversales , Enterovirus/genética , Femenino , Bocavirus Humano/genética , Humanos , Masculino , Metapneumovirus/genética , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Rhinovirus/genética , Adulto Joven
3.
Zygote ; 28(4): 333-336, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32345381

RESUMEN

Two farms applying reproductive technology for the Nellore beef cattle were selected. Both farms had the same technology programme of oestrous synchronization and embryo transfer, but management was different, especially regarding twins pregnancies. In the present study, we followed the farms from the moment of oestrous synchronization, embryo transfer (two per cow), until delivery and first care of the calves. In farm A, cows presenting twin pregnancies (5 from 13) were submitted to delivery induction, as well as calves and cows were monitored after birth. In farm B, such management was not followed with the twin pregnant cows (31 from 49). In both farms, freemartinism was detected, but this was not a problem as none of the animals would be selected for breeding. No dystocia was observed in farm A, while 48% of the twin pregnancies in farm B ended up in dystocia. Furthermore, the mortality rate of new-born calves in farm A was 10%, while in farm B it reached 32%. Although twin pregnancies remain a concern, we showed here that proper management during and after delivery minimizes animal and economic losses.


Asunto(s)
Transferencia de Embrión , Resultado del Embarazo/veterinaria , Preñez , Embarazo Múltiple , Animales , Animales Recién Nacidos , Bovinos , Ciclo Estral , Granjas , Femenino , Fertilización In Vitro , Freemartinismo/genética , Trabajo de Parto Inducido/veterinaria , Masculino , Mortalidad , Embarazo , Índice de Embarazo
4.
Cryobiology ; 84: 95-97, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30125538

RESUMEN

We evaluated the effects of the vitrification solution (i.e., ethylene glycol (EG) + dimethyl sulfoxide (DMSO) with or without propylene glycol (PG)) and of exposure time on the re-expansion and hatching rates of vitrified Bos indicus embryos. In vitro produced embryos (n = 1050) were divided into seven groups: control group (non-vitrified embryos) and six vitrification groups with different cryoprotectant concentrations and exposure times. After vitrification, embryos were cultured for determination of re-expansion and hatching rates. Vitrification with 25% DMSO +25% EG (exposure for 1 min and 20 s) resulted in the highest re-expansion (65.2%) and hatching (68.2%) rates. The lowest re-expansion and hatching rates were observed in vitrification with 12.5% DMSO + 25% EG + 12.5% PG with both tested exposure times (i.e., 3 min + 1 min and 1 min + 20 s). A combination of DMSO + EG is efficient to preserve blastocysts, especially following a short exposure time.


Asunto(s)
Blastocisto/efectos de los fármacos , Criopreservación/métodos , Crioprotectores/farmacología , Vitrificación , Animales , Bovinos , Dimetilsulfóxido/farmacología , Glicol de Etileno/farmacología , Femenino , Fertilización In Vitro , Propilenglicol/farmacología
6.
CNS Spectr ; 18(2): 82-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23253621

RESUMEN

INTRODUCTION: Clozapine is considered the gold standard for the treatment of patients with treatment-resistant schizophrenia (TRS); however, randomized controlled trials (RCT) of olanzapine showed efficacy similar to clozapine in patients with TRS. METHODS: A systematic review was conducted comparing clozapine with olanzapine in patients with TRS. Meta-analyses were performed for single outcome measures. Response to treatment was measured by the percentage of responders, or mean change or endpoint values of psychotic symptoms scales. Effect sizes were shown as relative risks (RR), or standardized mean differences, with 95% confidence intervals. FINDINGS: Seven RCT were included, comprising 648 patients. Five meta-analyses were performed. Olanzapine and clozapine had similar effects on dropout rates (RR = 0.93, CI95% = 0.77-1.12), PANSS total endpoints (SMD = 0.21, CI95% = -0.04-0.46), and PANSS total mean changes (SMD = 0.08, CI95% = -0.01-0.027). Clozapine was superior to olanzapine for PANSS positive (SMD = 0.51, CI95% = 0.17-0.86) and negative (SMD = 0.50, CI95% = 0.16-0.85) subscales. There was a trend toward high doses of olanzapine producing higher effect sizes for this drug. CONCLUSIONS: The results of this study suggest that clozapine is significantly more efficacious than olanzapine in improving positive and negative symptoms in TRS patients.


Asunto(s)
Antipsicóticos/uso terapéutico , Benzodiazepinas/uso terapéutico , Clozapina/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Adulto , Femenino , Humanos , Masculino , Olanzapina , Resultado del Tratamiento
7.
Transl Res ; 255: 109-118, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36526155

RESUMEN

Vertical transmission of Chikungunya virus (CHIKV) has been reported in humans, but the transmission routes have not been completely understood, and experimental animal models are needed to enable detailed investigation of the transmission and pathogenesis of congenital infections. The intertwining of immune response and virus components at the gestation/breastfeeding interfaces between mother and fetus/newborn may have effects during the offspring development. An experimental model of CHIKV was established by infecting pregnant BALB/c female mice that enabled confirmation that dams inoculated up to the 10th gestational day transmit CHIKV transplacentally to approximately 8.4% of the fetuses, resulting in severe teratogenic effects. CHIKV neutralizing antibodies were detected in sera from adult mice born to healthy females and breastfed by CHIKV-infected dams, while no neutralization was detected in sera from animals born to CHIKV-infected dams. Moreover, adult mice born to healthy dams and cross-fostered for breastfeeding by CHIKV-infected dams were resistant to challenge with CHIKV on the 90th day after birth. The animals also had reduced viral loads in brain and spleen as compared to controls. There was expression of fluorescent CHIKV non-structural protein, and detection of viral RNA by RT-PCR in breast tissue from infected dams. CHIKV RNA and proteins were also detected in breast milk retrieved from the stomachs of recently fed newborns. The experimental results were also complemented by the finding of CHIKV RNA in 6% of colostrum samples from healthy lactating women in a CHIKV-endemic area. Breastfeeding induces immune protection to challenge with CHIKV in mice.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Humanos , Embarazo , Femenino , Animales , Ratones , Virus Chikungunya/genética , Lactancia Materna , Lactancia , Anticuerpos Antivirales , Ratones Endogámicos BALB C , ARN
8.
Rev Col Bras Cir ; 49: e20223291, 2022.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-36074392

RESUMEN

OBJECTIVE: assess pain and opioid consumption in patients undergoing anesthetic techniques of spinal erector plane block and local anesthetic block in video-assisted thoracic surgery in the immediate postoperative period. METHODS: ninety-two patients undergoing video assisted thoracic surgery were randomized to receive ESPB or BAL before starting the surgical procedure. Using the numerical verbal scale, the primary outcome assessed was the patient's pain in the immediate postoperative period (POI). The secondary outcome comprises the assessment of opioid consumption in the IPP by quantifying the medication used in an equianalgesic dose of morphine expressed in milligrams, in the immediate post-anesthetic recovery period, 6h, 12h, and 24h after surgery. RESULTS: the EVN scores in the LBA and ESPB group in the POI had a mean of 0,8 (±1,89) vs 0,58 (±2,02) in the post-anesthesia care room (REPAI), 1,06 (±2,00) vs 1,30 (±2,30) in 6 hours of POI, 0,84 (±1,74) vs 1,19 (±2,01) within 12 hours of POI and 0,95 (±1,88) vs 1 ( ±1,66) within 24 hours of POI, all with p>0.05. Mean opioid consumption in the BAL and ESPB groups in the POI was 12.9 (± 10.4) mg vs 14.9 (±10.2) mg, respectively, with p = 0.416. Sixteen participants in the ESPB group and seventeen in the BAL group did not use opioids during the first 24 hours of the PO analyzed. CONCLUSION: local anesthesic block and ESP block techniques showed similar results in terms of low pain scores and opioid consumption during the period evaluated.


Asunto(s)
Analgésicos Opioides , Bloqueo Nervioso , Analgésicos Opioides/uso terapéutico , Anestésicos Locales , Humanos , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Cirugía Torácica Asistida por Video , Ultrasonografía Intervencional
9.
Sci Adv ; 8(37): eabo5400, 2022 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-36103544

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces mild or asymptomatic COVID-19 in most cases, but some patients develop an excessive inflammatory process that can be fatal. As the NLRP3 inflammasome and additional inflammasomes are implicated in disease aggravation, drug repositioning to target inflammasomes emerges as a strategy to treat COVID-19. Here, we performed a high-throughput screening using a 2560 small-molecule compound library and identified FDA-approved drugs that function as pan-inflammasome inhibitors. Our best hit, niclosamide (NIC), effectively inhibits both inflammasome activation and SARS-CoV-2 replication. Mechanistically, induction of autophagy by NIC partially accounts for inhibition of NLRP3 and AIM2 inflammasomes, but NIC-mediated inhibition of NAIP/NLRC4 inflammasome are autophagy independent. NIC potently inhibited inflammasome activation in human monocytes infected in vitro, in PBMCs from patients with COVID-19, and in vivo in a mouse model of SARS-CoV-2 infection. This study provides relevant information regarding the immunomodulatory functions of this promising drug for COVID-19 treatment.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Inflamasomas , Animales , Humanos , Agentes Inmunomoduladores , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR , SARS-CoV-2
10.
J Mol Cell Biol ; 14(4)2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35451490

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with a hyperinflammatory state and lymphocytopenia, a hallmark that appears as both signature and prognosis of disease severity outcome. Although cytokine storm and a sustained inflammatory state are commonly associated with immune cell depletion, it is still unclear whether direct SARS-CoV-2 infection of immune cells could also play a role in this scenario by harboring viral replication. We found that monocytes, as well as both B and T lymphocytes, were susceptible to SARS-CoV-2 infection in vitro, accumulating double-stranded RNA consistent with viral RNA replication and ultimately leading to expressive T cell apoptosis. In addition, flow cytometry and immunofluorescence analysis revealed that SARS-CoV-2 was frequently detected in monocytes and B lymphocytes from coronavirus disease 2019 (COVID-19) patients. The rates of SARS-CoV-2-infected monocytes in peripheral blood mononuclear cells from COVID-19 patients increased over time from symptom onset, with SARS-CoV-2-positive monocytes, B cells, and CD4+ T lymphocytes also detected in postmortem lung tissue. These results indicated that SARS-CoV-2 infection of blood-circulating leukocytes in COVID-19 patients might have important implications for disease pathogenesis and progression, immune dysfunction, and virus spread within the host.


Asunto(s)
COVID-19 , SARS-CoV-2 , Síndrome de Liberación de Citoquinas , Humanos , Leucocitos Mononucleares , Monocitos
12.
Arq Bras Cardiol ; 117(4): 657-663, 2021 10.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-34287569

RESUMEN

BACKGROUND: Endovascular stent placement in the right ventricular outflow tract (RVOT) has been an alternative to Blalock-Taussig (BT) surgery in the treatment of Tetralogy of Fallot (TOF) in symptomatic infants with low birth weight and complex anatomy. OBJECTIVE: To evaluate endovascular stent placement in the RVOT as a primary treatment for infants with TOF who are not candidates for BT surgery, and evaluate medium-term outcomes until the stent is removed during corrective surgery. METHODS: Six infants with TOF were treated with RVOT stenting from October 2015 to April 2018. Hemodynamic parameters were compared between the pre- and post-stenting periods. RESULTS: At the time of stenting, participants had a median age and weight of 146.5 days and 4.9 kg, respectively. Peak systolic gradient decreased from 63.5 mm Hg to 50.5 mm Hg, while the diameter of the left and right pulmonary arteries increased from 3.5 mm to 4.9 mm and 4.3 mm, respectively. The Nakata index increased from 96.5 mm to 108.3 mm; weight increased from 4.9 kg to 5.5 kg; and oxygen saturation, from 83.5% to 93%. There was one case of stent migration and two deaths, one caused by stent embolization and the other unrelated to study procedures. CONCLUSIONS: RVOT stenting is a promising alternative for the palliative treatment of TOF in infants with low birth weight and complex anatomy.


FUNDAMENTO: Tendo em vista os casos de lactentes sintomáticos com Tetralogia de Fallot (TF), baixo peso ao nascimento e anatomia complexa, o implante de stent na via de saída do ventrículo direito (VSVD) tem sido indicado alternativamente à cirurgia de Blalock-Taussig (BT). OBJETIVO: Avaliar o implante endovascular de stent na VSVD como abordagem primária no lactente com TF e não candidato à cirurgia de BT, bem como relatar seus resultados a médio prazo e até a retirada do stent na cirurgia corretiva. MÉTODOS: Entre outubro de 2015 e abril de 2018, uma série de seis lactentes portadores de TF receberam stents para desobstrução da VSVD. Os parâmetros hemodinâmicos foram comparados em períodos pré e pós-implante. RESULTADOS: As medianas de idade e peso no momento do procedimento foram de 146,5 dias e 4,9 kg, respectivamente. O gradiente sistólico máximo diminuiu de 63,5 mmHg para 50,5 mmHg, enquanto o diâmetro dos ramos pulmonares direito e esquerdo aumentou de 3,5 mm para 4,9 mm e 4,3 mm, respectivamente. O índice de Nakata aumentou de 96,5 mm para 108,3 mm; assim como o peso, de 4,9 kg para 5,5 kg. A saturação de oxigênio aumentou de 83,5% para 93%. Houve um caso de migração do stent e dois óbitos, um deles devido à embolização do stent e o outro não teve relação com o procedimento. CONCLUSÕES: O implante de stent na VSVD como procedimento paliativo na TF se mostra uma alternativa promissora para o tratamento de lactentes com má anatomia e baixo peso ao nascimento.


Asunto(s)
Procedimiento de Blalock-Taussing , Tetralogía de Fallot , Humanos , Lactante , Cuidados Paliativos , Arteria Pulmonar/cirugía , Estudios Retrospectivos , Tetralogía de Fallot/cirugía , Resultado del Tratamiento
13.
Rev Col Bras Cir ; 48: e20202890, 2021.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-33852704

RESUMEN

OBJECTIVE: to report the preoperative localization of pulmonary nodules with the placement of a guidewire oriented by Computed Tomography. METHODS: the nodules were marked using a needle in the shape of a hook or another in the shape of a Q, guided by tomography. The choice of the location for the marking was the shortest distance from the chest wall to the nodule. The marking procedure was performed under local anesthesia and a tomographic control was obtained immediately at the end. Patients were referred to the operating room. Surgical resection occurred less than two hours after the needle placement. RESULTS: between February 2017 and October 2019, 22 patients aged 43 to 82 years (mean 62.1) were included. The nodules had diameters that varied from 4 to 30 mm and the distance between the nodules and the pleural surface varied from 2 to 43 mm. The location and resection of the nodules were successfully performed in all cases. The guidewire was displaced in five cases. Five patients presented pneumothorax, with the space between the visceral and parietal pleura varying from 2 to 19 mm. In nine patients, an intraparenchymal hematoma of 6 to 35 mm in length was observed without signs, symptoms, or hemodynamic and ventilatory repercussions. The histopathological study was conclusive in all patients. CONCLUSIONS: the localization of pulmonary nodules through guidewires proved to be safe, reliable, and feasible in this series of cases. There was no need for surgical intervention to treat complications.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Nódulo Pulmonar Solitario , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Pulmón , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Persona de Mediana Edad , Cuidados Preoperatorios , Estudios Retrospectivos , Cirugía Torácica Asistida por Video
14.
Rev Col Bras Cir ; 48: e20202914, 2021.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-34133610

RESUMEN

OBJECTIVE: interstitial lung disease comprises a group of lung diseases with wide pathophysiological varieties. This paper aims to report the video thoracoscopic surgical biopsy in patients with interstitial lung disease through a single minimal chest incision, without orotracheal intubation, without chest drainage, and without the use of neuromuscular blockers. METHODS: this study is a series of 14 cases evaluated retrospectively, descriptively, where patients underwent a pulmonary surgical biopsy from January 2019 to January 2020. The patients included in the study had diffuse interstitial lung disease without a defined etiological diagnosis. RESULTS: none of the patients had transoperative complications, there was no need for chest drainage in the postoperative period, and the patients pain, assessed using the verbal scale, had a mode of 2 (minimum value of 1 and maximum of 4) in the post immediate surgery and 1 (minimum value of 1 and maximum of 3) at the time of hospital discharge. The length of hospital stay was up to 24 hours, with 12 patients being discharged on the same day of hospitalization. CONCLUSION: therefore, it is concluded in this series of cases that the performance of uniportal video-assisted thoracoscopic surgery procedures to perform lung biopsies, without orotracheal intubation, without chest drainage, and without the use of neuromuscular blockers, bring benefits to the patient without compromising his safety. Further larger studies are necessary to confirm the safety and efficiency of this method.


Asunto(s)
Enfermedades Pulmonares Intersticiales , Cirugía Torácica Asistida por Video , Biopsia , Drenaje , Humanos , Intubación Intratraqueal , Estudios Retrospectivos
15.
mBio ; 12(4): e0046321, 2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34340542

RESUMEN

Oropouche virus (OROV) infection of humans is associated with a debilitating febrile illness that can progress to meningitis or encephalitis. First isolated from a forest worker in Trinidad and Tobago in 1955, the arbovirus OROV has since been detected throughout the Amazon basin with an estimated 500,000 human infections over 60 years. Like other members of the family Peribunyaviridae, the viral genome exists as 3 single-stranded negative-sense RNA segments. The medium-sized segment encodes a viral glycoprotein complex (GPC) that is proteolytically processed into two viral envelope proteins, Gn and Gc, responsible for attachment and membrane fusion. There are no therapeutics or vaccines to combat OROV infection, and we have little understanding of protective immunity to infection. Here, we generated a replication competent chimeric vesicular stomatitis virus (VSV), in which the endogenous glycoprotein was replaced by the GPC of OROV. Serum from mice immunized by intramuscular injection with VSV-OROV specifically neutralized wild-type OROV, and using peptide arrays we mapped multiple epitopes within an N-terminal variable region of Gc recognized by the immune sera. VSV-OROV lacking this variable region of Gc was also immunogenic in mice producing neutralizing sera that recognize additional regions of Gc. Challenge of both sets of immunized mice with wild-type OROV shows that the VSV-OROV chimeras reduce wild-type viral infection and suggest that antibodies that recognize the variable N terminus of Gc afford less protection than those that target more conserved regions of Gc. IMPORTANCE Oropouche virus (OROV), an orthobunyavirus found in Central and South America, is an emerging public health challenge that causes debilitating febrile illness. OROV is transmitted by arthropods, and increasing mobilization has the potential to significantly increase the spread of OROV globally. Despite this, no therapeutics or vaccines have been developed to combat infection. Using vesicular stomatitis (VSV) as a backbone, we developed a chimeric virus bearing the OROV glycoproteins (VSV-OROV) and tested its ability to elicit a neutralizing antibody response. Our results demonstrate that VSV-OROV produces a strong neutralizing antibody response that is at least partially targeted to the N-terminal region of Gc. Importantly, vaccination with VSV-OROV reduces viral loads in mice challenged with wild-type virus. These data provide novel evidence that targeting the OROV glycoproteins may be an effective vaccination strategy to combat OROV infection.


Asunto(s)
Infecciones por Bunyaviridae/prevención & control , Genoma Viral , Orthobunyavirus/genética , Vesiculovirus/genética , Vesiculovirus/inmunología , Proteínas del Envoltorio Viral/genética , Animales , Anticuerpos Neutralizantes , Infecciones por Bunyaviridae/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Estomatitis Vesicular/virología , Replicación Viral
16.
Viruses ; 13(2)2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33540662

RESUMEN

Human respiratory syncytial virus (HRSV) is the most frequent cause of severe respiratory disease in children. The main targets of HRSV infection are epithelial cells of the respiratory tract, and the great majority of the studies regarding HRSV infection are done in respiratory cells. Recently, the interest on respiratory virus infection of lymphoid cells has been growing, but details of the interaction of HRSV with lymphoid cells remain unknown. Therefore, this study was done to assess the relationship of HRSV with A3.01 cells, a human CD4+ T cell line. Using flow cytometry and fluorescent focus assay, we found that A3.01 cells are susceptible but virtually not permissive to HRSV infection. Dequenching experiments revealed that the fusion process of HRSV in A3.01 cells was nearly abolished in comparison to HEp-2 cells, an epithelial cell lineage. Quantification of viral RNA by RT-qPCR showed that the replication of HRSV in A3.01 cells was considerably reduced. Western blot and quantitative flow cytometry analyses demonstrated that the production of HRSV proteins in A3.01 was significantly lower than in HEp-2 cells. Additionally, using fluorescence in situ hybridization, we found that the inclusion body-associated granules (IBAGs) were almost absent in HRSV inclusion bodies in A3.01 cells. We also assessed the intracellular trafficking of HRSV proteins and found that HRSV proteins colocalized partially with the secretory pathway in A3.01 cells, but these HRSV proteins and viral filaments were present only scarcely at the plasma membrane. HRSV infection of A3.01 CD4+ T cells is virtually unproductive as compared to HEp-2 cells, as a result of defects at several steps of the viral cycle: Fusion, genome replication, formation of inclusion bodies, recruitment of cellular proteins, virus assembly, and budding.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/fisiología , Linfocitos T/virología , Línea Celular , Humanos , Virus Sincitial Respiratorio Humano/genética , Proteínas Virales de Fusión/genética , Proteínas Virales de Fusión/metabolismo , Ensamble de Virus , Replicación Viral
17.
Front Neurosci ; 15: 674576, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34887719

RESUMEN

Oropouche virus (OROV) is an emerging arbovirus in South and Central Americas with high spreading potential. OROV infection has been associated with neurological complications and OROV genomic RNA has been detected in cerebrospinal fluid from patients, suggesting its neuroinvasive potential. Motivated by these findings, neurotropism and neuropathogenesis of OROV have been investigated in vivo in murine models, which do not fully recapitulate the complexity of the human brain. Here we have used slice cultures from adult human brains to investigate whether OROV is capable of infecting mature human neural cells in a context of preserved neural connections and brain cytoarchitecture. Our results demonstrate that human neural cells can be infected ex vivo by OROV and support the production of infectious viral particles. Moreover, OROV infection led to the release of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) and diminished cell viability 48 h post-infection, indicating that OROV triggers an inflammatory response and tissue damage. Although OROV-positive neurons were observed, microglia were the most abundant central nervous system (CNS) cell type infected by OROV, suggesting that they play an important role in the response to CNS infection by OROV in the adult human brain. Importantly, we found no OROV-infected astrocytes. To the best of our knowledge, this is the first direct demonstration of OROV infection in human brain cells. Combined with previous data from murine models and case reports of OROV genome detection in cerebrospinal fluid from patients, our data shed light on OROV neuropathogenesis and help raising awareness about acute and possibly chronic consequences of OROV infection in the human brain.

18.
Braz J Microbiol ; 52(2): 531-539, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33788178

RESUMEN

Accurate testing to detect SARS-CoV-2 RNA is key to counteract the virus spread. Nonetheless, the number of diagnostic laboratories able to perform qPCR tests is limited, particularly in developing countries. We describe the use of a virus-inactivating, denaturing solution (DS) to decrease virus infectivity in clinical specimens without affecting RNA integrity. Swab samples were collected from infected patients and from laboratory personnel using a commercially available viral transport solution and the in-house DS. Samples were tested by RT-qPCR, and exposure to infective viruses was also accessed by ELISA. The DS used did not interfere with viral genome detection and was able to maintain RNA integrity for up to 16 days at room temperature. Furthermore, virus loaded onto DS were inactivated, as attested by attempts to grow SARS-CoV-2 in cell monolayers after DS desalt filtration to remove toxic residues. The DS described here provides a strategy to maintain diagnostic accuracy and protects diagnostic laboratory personnel from accidental infection, as it has helped to protect our lab crew.


Asunto(s)
Prueba de COVID-19/métodos , COVID-19/diagnóstico , Estabilidad del ARN/efectos de los fármacos , ARN Viral/análisis , SARS-CoV-2/genética , Manejo de Especímenes/métodos , Pruebas Diagnósticas de Rutina , Genoma Viral/genética , Humanos , Desnaturalización Proteica/efectos de los fármacos , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2/efectos de los fármacos
19.
Heart Surg Forum ; 13(3): E161-4, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20534416

RESUMEN

We studied 12 consecutive patients with chronic ischemic myocardiopathy treated with bone marrow adult stem cell (ASC) transplantation and coronary artery bypass grafting (CABG). The aim of the study was to evaluate functional class (New York Heart Association), wall motion score index (WMSI), and ejection fraction by echocardiography and to evaluate myocardial perfusion by single-photon emission computed tomography (SPECT). Follow-up evaluations were performed at 3, 6, and 12 months. The results revealed functional class improvement until 12 months, a progressive increase in the ejection fraction of 15% to 20% in the first 6 months, and a progressive increase in the WMSI by 35% to 45% in 12 months. Evaluation of the WMSI in the stem cell and CABG areas separately revealed a similar improvement in the first 3 months and a better progression in the CABG area. SPECT images revealed perfusion improvements in ischemic areas and no difference in fibrous tissue areas. These preliminary results show the safety of the method and its reproducibility. When performed concomitantly with CABG, bone marrow ASC transplantation may improve functional class, ejection fraction, WMSI, and myocardial perfusion. This study will be completed with all patients followed up for 12 months and compared with a control group.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Puente de Arteria Coronaria , Isquemia Miocárdica/cirugía , Análisis de Varianza , Antígenos CD34 , Biopsia con Aguja Fina , Trasplante de Médula Ósea/estadística & datos numéricos , Estudios de Casos y Controles , Progresión de la Enfermedad , Humanos , Masculino , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/diagnóstico por imagen , Reperfusión Miocárdica , Estudios Prospectivos , Volumen Sistólico , Tomografía Computarizada de Emisión de Fotón Único , Ultrasonografía , Función Ventricular Izquierda
20.
mBio ; 11(5)2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32994321

RESUMEN

Human respiratory syncytial virus (HRSV) envelope glycoproteins traffic to assembly sites through the secretory pathway, while nonglycosylated proteins M and N are present in HRSV inclusion bodies but must reach the plasma membrane, where HRSV assembly happens. Little is known about how nonglycosylated HRSV proteins reach assembly sites. Here, we show that HRSV M and N proteins partially colocalize with the Golgi marker giantin, and the glycosylated F and nonglycosylated N proteins are closely located in the trans-Golgi, suggesting their interaction in that compartment. Brefeldin A compromised the trafficking of HRSV F and N proteins and inclusion body sizes, indicating that the Golgi is important for both glycosylated and nonglycosylated HRSV protein traffic. HRSV N and M proteins colocalized and interacted with sorting nexin 2 (SNX2), a retromer component that shapes endosomes in tubular structures. Glycosylated F and nonglycosylated N HRSV proteins are detected in SNX2-laden aggregates with intracellular filaments projecting from their outer surfaces, and VPS26, another retromer component, was also found in inclusion bodies and filament-shaped structures. Similar to SNX2, TGN46 also colocalized with HRSV M and N proteins in filamentous structures at the plasma membrane. Cell fractionation showed enrichment of SNX2 in fractions containing HRSV M and N proteins. Silencing of SNX1 and 2 was associated with reduction in viral proteins, HRSV inclusion body size, syncytium formation, and progeny production. The results indicate that HRSV structural proteins M and N are in the secretory pathway, and SNX2 plays an important role in the traffic of HRSV structural proteins toward assembly sites.IMPORTANCE The present study contributes new knowledge to understand HRSV assembly by providing evidence that nonglycosylated structural proteins M and N interact with elements of the secretory pathway, shedding light on their intracellular traffic. To the best of our knowledge, the present contribution is important given the scarcity of studies about the traffic of HRSV nonglycosylated proteins, especially by pointing to the involvement of SNX2, a retromer component, in the HRSV assembly process.


Asunto(s)
Precursor de Proteína beta-Amiloide/metabolismo , Interacciones Microbiota-Huesped , Proteínas de la Nucleocápside/metabolismo , Virus Sincitial Respiratorio Humano/fisiología , Proteínas Virales/metabolismo , Ensamble de Virus , Precursor de Proteína beta-Amiloide/genética , Proteínas Portadoras , Aparato de Golgi/metabolismo , Proteínas de la Matriz de Golgi/metabolismo , Células HeLa , Humanos , Transporte de Proteínas
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