Radiological Findings Increased the Successful of COVID-19 Diagnosis in Hospitalized Patients Suspected of Respiratory Viral Infection but with a Negative First SARS-CoV-2 RT-PCR Result.

SARS-CoV-2 is the etiological agent of COVID-19 and may evolve from asymptomatic disease to fatal outcomes. Real-time reverse-transcription polymerase chain reaction (RT-PCR) screening is the gold standard to diagnose severe accurate respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but this test is not 100% accurate, as false negatives can occur. We aimed to evaluate the potential false-negative results in hospitalized patients suspected of viral respiratory disease but with a negative previous SARS-CoV-2 RT-PCR and analyze variables that may increase the success of COVID-19 diagnosis in this group of patients. A total of 55 hospitalized patients suspected of viral respiratory disease but with a previous negative RT-PCR result for SARS-CoV-2 were included. All the participants had clinical findings related to COVID-19 and underwent a second SARS-CoV-2 RT-PCR. Chest-computed axial tomography (CT) was used as an auxiliary tool for COVID-19 diagnosis. After the second test, 36 patients (65.5%) were positive for SARS-CoV-2 (COVID-19 group), and 19 patients (34.5%) were negative (controls). There were differences between the groups in the platelet count and the levels of D-dimer, procalcitonin, and glucose (p < 0.05). Chest CT scans categorized as COVID-19 Reporting and Data System 5 (CO-RADS 5) were more frequent in the COVID-19 group than in the control group (91.7% vs. 52.6%; p = 0.003). CO-RADS 5 remained an independent predictor of COVID-19 diagnosis in a second SARS-CoV-2 screening (p = 0.013; odds ratio = 7.0, 95% confidence interval 1.5−32.7). In conclusion, chest CT classified as CO-RADS 5 was an independent predictor of a positive second SARS-CoV-2 RT-PCR, increasing the odds of COVID-19 diagnosis by seven times. Based on our results, in hospitalized patients with a chest CT classified as CO-RADS 5, a second SARS-CoV-2 RT-PCR test should be mandatory when the first one is negative. This approach could increase SARS-CoV-2 detection up to 65% and could allow for isolation and treatment, thus improving the patient outcome and avoiding further contagion.

Hyperglycemia and Angiotensin-Converting Enzyme 2 in Pulmonary Function in the Context of SARS-CoV-2 Infection.

Since the appearance of the severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003 in China, diabetes mellitus (DM) and hyperglycemia in patients infected with SARS-CoV, represent independent predictors of mortality. Therefore, metabolic control has played a major role in the prognosis of these patients. In the current pandemic of coronavirus disease 19 (COVID-19), multiple studies have shown that DM is one of the main comorbidities associated with COVID-19 and higher risk of complications and death. The incidence and prevalence of COVID-19 complications and death related with hyperglycemia in patients with or without DM are high. There are many hypotheses related with worse prognosis and death related to COVID-19 and/or hyperglycemia. However, the information about the interplay between hyperglycemia and angiotensin-converting enzyme 2 (ACE2), the critical receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in the context of SARS-CoV-2 infection, is almost null, but there is enough information to consider the possible participation of hyperglycemia in the glycation of this protein, unleashing a pool of reactions leading to acute respiratory distress syndrome and death in patients with COVID-19. In this document we investigated the current evidence related with ACE2 as a key element within the pathophysiological mechanism related with hyperglycemia extrapolating it to context of SARS-CoV-2 infection and its relationship with worse prognosis and death for COVID-19.

Serum cytokine, chemokine, and growth factor profiles and their modulation in inflammatory bowel disease.

Ulcerative colitis (UC) and Crohn disease (CD) are the most common forms of inflammatory bowel disease (IBD). Because these subtypes of IBD are characterized by periods of activity and remission, an understanding of the modulation of biochemical markers with the clinical features of IBD or its treatment, may be useful for determining the correct treatment protocol.This study aimed to evaluate the serum levels of 27 protein biomarkers to determine their association with IBD, correlation with clinical findings of disease, and modulation according to the pharmacologic therapy.A case-control study was carried out in Zacatecas, Mexico. The 27 protein profiles of serum from 53 participants (23 UC, 11 CD, and 19 controls) were evaluated using the Pro Human Cytokine 27-Plex immunoassay (Bio-Rad).Considering the controls as a reference, the group with IBD endoscopic activity showed higher serum levels of granulocyte colony-stimulating factor (G-CSF), interleukin 1 receptor antagonist (IL-1Ra), and platelet-derived growth factor BB (PDGF-BB) (P < .05). Interferon-induced protein 10 (IP-10) was associated with extraintestinal symptoms of disease (P = .041). Both PDGF-BB and interleukin 6 (IL-6) showed the strongest correlations with clinical features of IBD. Levels of IL-6, IL-7, and monocyte chemoattractant protein 1 were higher with 5-aminosalicylic acid (5-ASA) + Azathioprine therapy than controls (P < .05). Combined therapy with 5-ASA + Adalimumab led to the strongest changes in marker modulation: IL-4, IL-5, IL-15, and PDGF-BB, were upregulated (P < .05).Elevated serum levels of G-CSF, IL-1Ra, and PDGF-BB were associated with IBD endoscopic activity, and of IP-10 with extraintestinal manifestations of IBD. Combined therapy of 5-ASA + Adalimumab produced significant upregulation of IL-4, IL-5, IL-15, and PDGF-BB. This information may be useful for deciding on the course of pharmacologic therapy for patients with IBD and for generating new therapy alternatives to improve the outcome of patients with IBD.

Electrospun Polycaprolactone Fibrous Membranes Containing Ag, TiO2 and Na2Ti6O13 Particles for Potential Use in Bone Regeneration.

Biocompatible and biodegradable membrane treatments for regeneration of bone are nowadays a promising solution in the medical field. Bioresorbable polymers are extensively used in membrane elaboration, where polycaprolactone (PCL) is used as base polymer. The goal of this work was to improve electrospun membranes' biocompatibility and antibacterial properties by adding micro- and nanoparticles such as Ag, TiO2 and Na2Ti6O13. Micro/nanofiber morphologies of the obtained membranes were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, energy-dispersive X-ray spectroscopy and a tensile test. Also, for this study optical microscopy was used to observe DAPI-stained cells. Membranes of the different systems were electrospun to an average diameter of 1.02⁻1.76 µm. To evaluate the biological properties, cell viability was studied by growing NIH/3T3 cells on the microfibers. PCL/TiO2 strength was enhanced from 0.6 MPa to 6.3 MPa in comparison with PCL without particles. Antibacterial activity was observed in PCL/TiO2 and PCL/Na2Ti6O13 electrospun membranes using Staphylococcus aureus bacteria. Bioactivity of the membranes was confirmed with simulated body fluid (SBF) treatment. From this study, the ceramic particles TiO2 and Na2Ti6O13, combined with a PCL matrix with micro/nanoparticles, enhanced cell proliferation, adhesion and antibacterial properties. The electrospun composite with Na2Ti6O13 can be considered viable for tissue regenerative processes.

Circulating levels of specific members of chromosome 19 microRNA cluster are associated with preeclampsia development.

PURPOSE: To perform serum microRNA expression profiling to identify members of chromosome 19 miRNA cluster involved in preeclampsia development. METHODS: Serum chromosome 19 miRNA cluster microRNA expression profiling was evaluated at 12, 16, and 20 gestational weeks and at the time of preeclampsia diagnosis, in women who developed preeclampsia (WWD-PE; n = 16) and controls (n = 18) using TaqMan low density array plates. RESULTS: A total of 51 chromosome 19 microRNA cluster members were evaluated. The circulating hsa-miRs 512-3p, 518f-3p, 520c-3p, and 520d-3p, were differentially expressed between groups (P < 0.05). Compared with controls, serum levels of hsa-miR-518f-3p at 20 GW were useful for identifying WWD-Mild-PE (P = 0.035) and WWD-Severe-PE (P = 0.007). CONCLUSIONS: Serum hsa-miRs 512-3p, 518f-3p, 520c-3p, and 520d-3p, are differentially expressed between WWD-PE and controls and their role in the development of preeclampsia should be investigated further.

A baseline process for the production, recovery, and purification of bacterial influenza vaccine candidates.

The current commercial system for influenza vaccine production depends on the culture of virus in embryonated eggs--a strategy that is both costly and poorly scalable. Consequently, a sudden pandemic event with a demand for millions of vaccine doses in a short time could readily overwhelm the available world production capacity. In this communication, we present a process that uses Escherichia coli for scalable production of recombinant vaccine candidates against influenza. A monomeric and a dimeric fragment of hemagglutinin of the influenza A H1N1/2009 virus were successfully expressed in a BL21 (DE3) pLysS variety of C41 E. coli. We present results from batch processes where induction is made with isopropyl thiogalactoside and from fed-batch experiments where expression is induced using lactose/glucose pulses. Concentrations in the range of 1.188-0.605 g/L of recombinant protein were observed in 2-L stirred tank bioreactors. The genetic construct included an N-terminal histidine tag sequence that facilitated recovery, purification, and proper refolding of the vaccine candidate by affinity chromatography in columns loaded with Ni(+2) . The proteins produced by this strategy selectively and specifically recognizes antibodies from patients diagnosed as positive to influenza A H1N1/2009. Overall protein recovery yields between 30.0 and 34.7% were typically observed. Based on these yields, a production of 4.6 × 10(3) doses L(-3) day(-1) is feasible.

Construction of a Nocardia brasiliensis fluorescent plasmid to study Actinomycetoma pathogenicity.

Nocardia brasiliensis, is a bacteria that lives as saprophyte in soil and causes a disease called actinomycetoma in both human and animals. Nocardia brasiliensis is an intracellular, facultative bacterium that replicates and survives within host macrophages. The mechanisms involved in the evasion of the microbicidal actions of macrophages remain unclear. The filamentous growth of N. brasiliensis is resistant to unicellular preparations, leading to inaccurate quantification of bacterial numbers by means of colony forming units (CFU). As successful survival studies with green fluorescent protein (GFP)-expressing bacterial strains have been reported, we constructed a recombinant GFP-expressing strain of N. brasiliensis. The virulence of the modified strain is maintained because it induces mycetoma in BALB/c mice. This new strain can be used for bacterial survival assays using cytometry and to elucidate the pathogenicity mechanisms in Actinomycetoma infection.