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Biology subjects

Oliveira, F. R.

Publications and source records attributed to Oliveira, F. R..

3 recordsLinked to original sources

Inhibition of Bruton's tyrosine kinase activity attenuates trauma-induced multiple organ dysfunction in rats

ObjectiveThe aim of this study was to investigate (a) the potential of the Brutons tyrosine kinase (BTK) inhibitors (BTKi) acalabrutinib and fenebrutinib to reduce multiple organ dysfunction syndrome (MODS) in acute and chronic hemorrhagic shock (HS) rat models and (b) whether treatment with either acalabrutinib or fenebrutinib attenuates BTK, NF-{kappa}B and NLRP3 activation in HS. BackgroundThe MODS caused by an excessive systemic inflammatory response following trauma is associated with a high morbidity and mortality. The protein BTK is known to play a role in the activation of the NLRP3 inflammasome, which is a key component of the innate inflammatory response. However, its role in trauma-hemorrhage is unknown. MethodsAcute and chronic HS rat models were performed to determine the influence of acalabrutinib or fenebrutinib on MODS. The activation of BTK, NF-{kappa}B and NLRP3 pathways were analyzed by western blot in the kidney. ResultsWe demonstrated that (a) HS caused organ injury and/or dysfunction and hypotension (post resuscitation) in rats, while (b) treatment of HS-rats with either acalabrutinib or fenebrutinib attenuated the organ injury and dysfunction in acute and chronic HS models and (c) reduced the activation of BTK, NF-{kappa}B and NLRP3 pathways in the kidney. ConclusionOur results point to a role of BTK in the pathophysiology of organ injury and dysfunction caused by trauma/hemorrhage and indicate that BTK inhibitors may be repurposed as a potential therapeutic approach for MODS after trauma and/or hemorrhage. MINI-ABSTRACTThis study evaluated the role of Brutons tyrosine kinase (BTK) in trauma/hemorrhage. Patients with trauma had elevated gene expression of BTK. The BTK inhibitors acalabrutinib (irreversible) and fenebrutinib (reversible) attenuated the trauma-induced multiple organ dysfunction in rats with hemorrhagic shock, indicating that BTK could be a potential therapeutic target.

pharmacology and toxicology

Infection of human lymphomononuclear cells by SARS-CoV-2

Although SARS-CoV-2 severe infection is associated with a hyperinflammatory state, lymphopenia is an immunological hallmark, and correlates with poor prognosis in COVID-19. However, it remains unknown if circulating human lymphocytes and monocytes are susceptible to SARS-CoV-2 infection. In this study, SARS-CoV-2 infection of human peripheral blood mononuclear cells (PBMCs) was investigated both in vitro and in vivo. We found that in vitro infection of whole PBMCs from healthy donors was productive of virus progeny. Results revealed that monocytes, as well as B and T lymphocytes, are susceptible to SARS-CoV-2 active infection and viral replication was indicated by detection of double-stranded RNA. Moreover, flow cytometry and immunofluorescence analysis revealed that SARS-CoV-2 was frequently detected in monocytes and B lymphocytes from COVID-19 patients, and less frequently in CD4+T lymphocytes. The rates of SARS-CoV-2-infected monocytes in PBMCs from COVID-19 patients increased over time from symptom onset. Additionally, SARS-CoV-2-positive monocytes and B and CD4+T lymphocytes were detected by immunohistochemistry in post mortem lung tissue. SARS-CoV-2 infection of blood circulating leukocytes in COVID-19 patients may have important implications for disease pathogenesis, immune dysfunction, and virus spread within the host.

microbiology

Involvement of gestational weight and body composition on autonomic recovery following aerobic exercise in children: a prospective, observational and analytical study

Birth weight (BW) can be used to assess the health status of the newborn. However, its impacts on later in life regarding heart rate (HR) variability (HRV) is not totally clear. We aimed to analyze the involvement of BW and body composition on HRV recovery following aerobic exercise in children. The study was conducted in healthy children 9 to 11 years of age (40 females and 27 males) divided into two groups: G1 (BW < 3400 grams, N = 33) and G2 (BW > 3400 grams, N = 34). The volunteers completed an experimental protocol of submaximal aerobic exercise on a treadmill and remained seated for 30 minutes after exercise. Systolic (SAP) and diastolic arterial pressure (DAP), respiratory rate (f) and HRV were analyzed before and during recovery from exercise. SAP and f were significantly decreased 30 minutes after exercise compared to 1 minute after exercise in G1 and G2. Mean HR, high frequency band of spectral analysis (HF), root mean square of successive interbeat intervals difference, SD1 index and mean lenght were diminished 0 to 5 minutes after exercise compared to rest in G2 while maximum lenght increased 0 to 5 minutes after exercise compared to resting in G2. Linear regression revealed association of fat percentage and BW with nonlinear HRV recovery. In conclusion, autonomic recovery after exercise was somewhat delayed in children with high BW. BW and fat percentage slightly influence HRV recovery.

neuroscience