SARS-CoV-2 Vaccine Effectiveness in Hospitalized Patients: A Multicenter Test-Negative Case-Control Study.

BACKGROUND: Phase III clinical trials have documented the efficacy of the SARS-CoV-2 vaccines in preventing symptomatic COVID-19. Nonetheless, it is imperative to continue analyzing the clinical response to different vaccines in real-life studies. Our objective was to evaluate the effectiveness of five different vaccines in hospitalized patients with COVID-19 during the third COVID-19 outbreak in Mexico dominated by the Delta variant. METHODS: A test-negative case-control study was performed in nine tertiary-care hospitals for COVID-19. We estimated odds ratios (OR) adjusted by variables related a priori with the likelihood of SARS-CoV-2 infection and its severity. RESULTS: We studied 761 subjects, 371 cases, and 390 controls with a mean age of 53 years (SD, 17 years). Overall, 51% had a complete vaccination scheme, and an incomplete scheme (one dose from a scheme of two), 14%. After adjustment for age, gender, obesity, and diabetes mellitus, we found that the effectiveness of avoiding a SARS-CoV-2 infection when hospitalized with at least one vaccination dose was 71% (OR 0.29, 95% CI 0.19-0.45), that of an incomplete vaccination scheme, 67% (OR 0.33, 95% CI 0.18-0.62), and that of any complete vaccination scheme, 73% (OR 0.27, 95% CI 0.17-0.43). CONCLUSIONS: The SARS-CoV-2 vaccination program showed effectiveness in preventing SARS-CoV-2 infection in hospitalized patients during a Delta variant outbreak.

Supervised Machine Learning Methods for Seasonal Influenza Diagnosis.

Influenza has been a stationary disease in Mexico since 2009, and this causes a high cost for the national public health system, including its detection using RT-qPCR tests, treatments, and absenteeism in the workplace. Despite influenza's relevance, the main clinical features to detect the disease defined by international institutions like the World Health Organization (WHO) and the United States Centers for Disease Control and Prevention (CDC) do not follow the same pattern in all populations. The aim of this work is to find a machine learning method to facilitate decision making in the clinical differentiation between positive and negative influenza patients, based on their symptoms and demographic features. The research sample consisted of 15480 records, including clinical and demographic data of patients with a positive/negative RT-qPCR influenza tests, from 2010 to 2020 in the public healthcare institutions of Mexico City. The performance of the methods for classifying influenza cases were evaluated with indices like accuracy, specificity, sensitivity, precision, the f1-measure and the area under the curve (AUC). Results indicate that random forest and bagging classifiers were the best supervised methods; they showed promise in supporting clinical diagnosis, especially in places where performing molecular tests might be challenging or not feasible.

Voltage-gated sodium channels: from roles and mechanisms in the metastatic cell behavior to clinical potential as therapeutic targets.

During the second half of the last century, the prevalent knowledge recognized the voltage-gated sodium channels (VGSCs) as the proteins responsible for the generation and propagation of action potentials in excitable cells. However, over the last 25 years, new non-canonical roles of VGSCs in cancer hallmarks have been uncovered. Their dysregulated expression and activity have been associated with aggressive features and cancer progression towards metastatic stages, suggesting the potential use of VGSCs as cancer markers and prognostic factors. Recent work has elicited essential information about the signalling pathways modulated by these channels: coupling membrane activity to transcriptional regulation pathways, intracellular and extracellular pH regulation, invadopodia maturation, and proteolytic activity. In a promising scenario, the inhibition of VGSCs with FDA-approved drugs as well as with new synthetic compounds, reduces cancer cell invasion in vitro and cancer progression in vivo. The purpose of this review is to present an update regarding recent advances and ongoing efforts to have a better understanding of molecular and cellular mechanisms on the involvement of both pore-forming α and auxiliary ß subunits of VGSCs in the metastatic processes, with the aim at proposing VGSCs as new oncological markers and targets for anticancer treatments.

Clinical validation of 3D-printed swabs in adults and children for SARS-CoV-2 detection.

Throughout the entire coronavirus disease 19 (COVID-19) pandemic, there were disruptions in the supply chain of test materials around the world, primarily in poor- and middle-income countries. The use of 3D prints is an alternative to address swab supply shortages. In this study, the feasibility of the clinical use of 3D-printed swabs for oropharyngeal and nasopharyngeal sampling for the detection of SARS-CoV-2 infection was evaluated. For that purpose, paired samples with the 3D printed and the control swabs were taken from 42 adult patients and 10 pediatric patients, and the results obtained in the detection of SARS-CoV-2 by reverse transcription and quantitative polymerase chain reaction (RT-qPCR) were compared. Additionally, in those cases where the result was positive for SARS-CoV-2, the viral load was calculated by means of a mathematical algorithm proposed by us. For both adults and children, satisfactory results were obtained in the detection of SARS-CoV-2 by RT-qPCR; no significant differences were found in the quantification cycle values between the 3D-printed swab samples and the control samples. Furthermore, we corroborated that the 3D-printed swabs caused less discomfort and pain at the time of sampling. In conclusion, this study shows the feasibility of routinely using 3D-printed swabs for both adults and children. In this way, it is possible to maintain local and cheaper consumption along with fewer distribution difficulties.

COVID-19: critical case of a patient with an atypical manifestation of the disease.

BACKGROUND: COVID-19 was initially described as a severe acute respiratory disease that could drive to pneumonia, compromising the life of the patients in the worst scenario. However, even though in most of the cases the respiratory symptoms are still the most common manifestations of the disease, nowadays it is considered as a complex multisystem illness, affecting a variety of organs and tissues. Asymptomatic and atypic cases have also been described, where symptoms are not related to those first described, as is the case of this report. CASE PRESENTATION: On November 23, 2020, a 53-year-old woman goes to the emergency room due to gastrointestinal symptoms. The admission diagnosis was inflammatory bowel disease and a mild event of idiopathic chronic ulcerative colitis, and the initial treatment was focused on the metabolic acidosis, and the reestablishment the hydroelectrolytic and hemodynamic balance. Then, she was transferred to the Gastroenterology Unit where she was treated for one week. During her hospitalization, she showed a refractory shock caused by progressive organ deterioration (renal and neurological), requiring a double-vasopressor support, oxygenation, and ventilation. Considering the laboratory tests results and computed tomography scans, a COVID-19 test was carried out, obtaining a positive result with a high viral load. The S gene of the virus was amplified and sequenced, finding an uncommon mutation rarely reported worldwide. After considerable systemic deterioration, the patient presented cardiorespiratory arrest, with no response and died on December 1, after 8 days of hospitalization. CONCLUSIONS: In this report we describe the pathogenesis, clinical manifestations, and outcome of a patient with atypical COVID-19 symptoms (mainly gastrointestinal), rapidly evolving and with lethal consequences. Therefore, it is important to emphasize the need to strengthen patient surveillance in health centers, including those who do not present typical symptoms of COVID-19. In addition, it will be important to track the identified mutation (H1058Y) in the S viral gene and assess whether it could be associated with a different clinical manifestation of the disease or if it was just an isolated event.

Contribution of voltage-gated sodium channel ß-subunits to cervical cancer cells metastatic behavior.

BACKGROUND: Voltage-gated sodium (NaV) channels are heteromeric proteins consisting of a single pore forming α-subunit associated with one or two auxiliary ß-subunits. These channels are classically known for being responsible of action potential generation and propagation in excitable cells; but lately they have been reported as widely expressed and regulated in several human cancer types. We have previously demonstrated the overexpression of NaV1.6 channel in cervical cancer (CeCa) biopsies and primary cultures, and its contribution to cell migration and invasiveness. Here, we investigated the expression of NaV channels ß-subunits (NaVßs) in the CeCa cell lines HeLa, SiHa and CaSki, and determined their contribution to cell proliferation, migration and invasiveness. METHODS: We assessed the expression of NaVßs in CeCa cell lines by performing RT-PCR and western blotting experiments. We also evaluated CeCa cell lines proliferation, migration, and invasion by in vitro assays, both in basal conditions and after inducing changes in NaVßs levels by transfecting specific cDNAs or siRNAs. The potential role of NaVßs in modulating the expression of NaV α-subunits in the plasma membrane of CeCa cells was examined by the patch-clamp whole-cell technique. Furthermore, we investigated the role of NaVß1 on cell cycle in SiHa cells by flow cytometry. RESULTS: We found that the four NaVßs are expressed in the three CeCa cell lines, even in the absence of functional NaV α-subunit expression in the plasma membrane. Functional in vitro assays showed differential roles for NaVß1 and NaVß4, the latter as a cell invasiveness repressor and the former as a migration abolisher in CeCa cells. In silico analysis of NaVß4 expression in cervical tissues corroborated the downregulation of this protein expression in CeCa vs normal cervix, supporting the evidence of NaVß4's role as a cell invasiveness repressor. CONCLUSIONS: Our results contribute to the recent conception about NaVßs as multifunctional proteins involved in cell processes like ion channel regulation, cell adhesion and motility, and even in metastatic cell behaviors. These non-canonical functions of NaVßs are independent of the presence of functional NaV α-subunits in the plasma membrane and might represent a new therapeutic target for the treatment of cervical cancer.

Increase of CaV3 channel activity induced by HVA ß1b-subunit is not mediated by a physical interaction.

OBJECTIVE: Low voltage-activated (LVA) calcium channels are crucial for regulating oscillatory behavior in several types of neurons and other excitable cells. LVA channels dysfunction has been implicated in epilepsy, neuropathic pain, cancer, among other diseases. Unlike for High Voltage-Activated (HVA) channels, voltage-dependence and kinetics of currents carried by recombinant LVA, i.e., CaV3 channels, are quite similar to those observed in native currents. Therefore, whether these channels are regulated by HVA auxiliary subunits, remain controversial. Here, we used the α1-subunits of CaV3.1, CaV3.2, and CaV3.3 channels, together with HVA auxiliary ß-subunits to perform electrophysiological, confocal microscopy and immunoprecipitation experiments, in order to further explore this possibility. RESULTS: Functional expression of CaV3 channels is up-regulated by all four ß-subunits, although most consistent effects were observed with the ß1b-subunit. The biophysical properties of CaV3 channels were not modified by any ß-subunit. Furthermore, although ß1b-subunits increased colocalization of GFP-tagged CaV3 channels and the plasma membrane of HEK-293 cells, western blots analysis revealed the absence of physical interaction between CaV3.3 and ß1b-subunits as no co-immunoprecipitation was observed. These results provide solid evidence that the up-regulation of LVA channels in the presence of HVA-ß1b subunit is not mediated by a high affinity interaction between both proteins.

Contribution of S4 segments and S4-S5 linkers to the low-voltage activation properties of T-type CaV3.3 channels.

Voltage-gated calcium channels contain four highly conserved transmembrane helices known as S4 segments that exhibit a positively charged residue every third position, and play the role of voltage sensing. Nonetheless, the activation range between high-voltage (HVA) and low-voltage (LVA) activated calcium channels is around 30-40 mV apart, despite the high level of amino acid similarity within their S4 segments. To investigate the contribution of S4 voltage sensors for the low-voltage activation characteristics of CaV3.3 channels we constructed chimeras by swapping S4 segments between this LVA channel and the HVA CaV1.2 channel. The substitution of S4 segment of Domain II in CaV3.3 by that of CaV1.2 (chimera IIS4C) induced a ~35 mV shift in the voltage-dependence of activation towards positive potentials, showing an I-V curve that almost overlaps with that of CaV1.2 channel. This HVA behavior induced by IIS4C chimera was accompanied by a 2-fold decrease in the voltage-dependence of channel gating. The IVS4 segment had also a strong effect in the voltage sensing of activation, while substitution of segments IS4 and IIIS4 moved the activation curve of CaV3.3 to more negative potentials. Swapping of IIS4 voltage sensor influenced additional properties of this channel such as steady-state inactivation, current decay, and deactivation. Notably, Domain I voltage sensor played a major role in preventing CaV3.3 channels to inactivate from closed states at extreme hyperpolarized potentials. Finally, site-directed mutagenesis in the CaV3.3 channel revealed a partial contribution of the S4-S5 linker of Domain II to LVA behavior, with synergic effects observed in double and triple mutations. These findings indicate that IIS4 and, to a lesser degree IVS4, voltage sensors are crucial in determining the LVA properties of CaV3.3 channels, although the accomplishment of this function involves the participation of other structural elements like S4-S5 linkers.

CDKN3 mRNA as a Biomarker for Survival and Therapeutic Target in Cervical Cancer.

The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10-6, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5-10, p = 3.3 x 10-6, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC.