Ebola and marburgviruses, members of the family Filoviridae, can cause severe hemorrhagic fever in humans. The ongoing Ebola virus (EBOV) disease epidemic in Western Africa claimed more than 11,300 ...lives and was associated with secondary cases outside Africa, demonstrating that filoviruses pose a global health threat. Bats constitute an important natural reservoir of filoviruses, including viruses of the recently identified Cuevavirus genus within the Filoviridae family. However, the interactions of filoviruses with bat cells are incompletely understood. Here, we investigated whether filoviruses employ different strategies to enter human and bat cells. For this, we examined host cell entry driven by glycoproteins (GP) from all filovirus species into cell lines of human and fruit bat origin. We show that all GPs were able to mediate entry into human and most fruit bat cell lines with roughly comparable efficiency. In contrast, the efficiency of entry into the cell line EidNi/41 derived from a straw-colored fruit bat varied markedly between the GPs of different filovirus species. Furthermore, inhibition studies demonstrated that filoviruses employ the same host cell factors for entry into human, non-human primate and fruit bat cell lines, including cysteine proteases, two pore channels and NPC1 (Niemann-Pick C1 molecule). Finally, processing of GP by furin and the presence of the mucin-like domain in GP were dispensable for entry into both human and bat cell lines. Collectively, these results show that filoviruses rely on the same host cell factors for entry into human and fruit bat cells, although the efficiency of the usage of these factors might differ between filovirus species.
The pathogenesis of type 2 diabetes (T2D) is associated with a progressive loss of pancreatic β‐cell mass. It is known that miR‐146a, miR‐34a, and miR‐375 are involved in β‐cell functionality. In ...this work, we evaluated the levels of these miRNAs in normal‐glycaemic individuals, pre‐diabetic, and T2D patients in relation to β‐cell functionality, insulin resistance, and metabolic parameters. The relative expression of the miRNAs was evaluated in serum samples by real‐time polymerase chain reaction. In a principal component analysis, we observed that T2D patients and pre‐diabetic individuals were not associated with β‐cell functionality. However, in a correlation matrix analysis, we detected that miR‐34a was related to miR‐146a and insulin resistance. The relative expression of miR‐375 was correlated with cholesterol and low‐density lipoprotein levels. A decrease of β‐cell function in pre‐diabetic individuals and T2D patients was observed. The insulin resistance was higher in pre‐diabetic individuals and T2D patients. The relative expression of miR‐146a in pre‐diabetic individuals, T2D patients with insulin treatment, and T2D patients with nephropathy and diabetic foot was decreased. In addition, miR‐34a was increased in T2D patients who were overweight and obese. The relative expression of miR‐375 was increased in T2D patients with poor glycaemic control, while a decrease was seen in T2D patients with nephropathy and diabetic foot. Circulating miR‐375, miR‐34a, and miR‐146a were not associated with β‐cell functionality, but their expression was differentially affected by glycaemia, obesity, insulin treatment, and the presence of nephropathy and diabetic foot.
Emerging viruses such as severe fever and thrombocytopenia syndrome virus (SFTSV) and Ebola virus (EBOV) are responsible for significant morbidity and mortality. Host cell proteases that process the ...glycoproteins of these viruses are potential targets for antiviral intervention. The aspartyl protease signal peptide peptidase (SPP) has recently been shown to be required for processing of the glycoprotein precursor, Gn/Gc, of Bunyamwera virus and for viral infectivity. Here, we investigated whether SPP is also required for infectivity of particles bearing SFTSV-Gn/Gc. Entry driven by the EBOV glycoprotein (GP) and the Lassa virus glycoprotein (LASV-GPC) depends on the cysteine proteases cathepsin B and L (CatB/CatL) and the serine protease subtilisin/kexin-isozyme 1 (SKI-1), respectively, and was examined in parallel for control purposes. We found that inhibition of SPP and SKI-1 did not interfere with SFTSV Gn + Gc-driven entry but, unexpectedly, blocked entry mediated by EBOV-GP. The inhibition occurred at the stage of proteolytic activation and the SPP inhibitor was found to block CatL/CatB activity. In contrast, the SKI-1 inhibitor did not interfere with CatB/CatL activity but disrupted CatB localization in endo/lysosomes, the site of EBOV-GP processing. These results underline the potential of protease inhibitors for antiviral therapy but also show that previously characterized compounds might exert broader specificity than initially appreciated and might block viral entry via diverse mechanisms.
Premise
Gene flow in riparian ecosystems is influenced by landscape features such as orography, climate, and salinity. The downstream increase in genetic diversity (DIGD) hypothesis states that the ...unidirectionality of the watercourse causes an accumulation of genetic diversity toward downstream populations, while upstream populations are more structured and less diverse, especially in water‐dispersed organisms.
Methods
We used chloroplast and nuclear microsatellites to characterize genetic diversity, structure, and gene flow patterns among populations of Salix humboldtiana across an elevation and salinity gradient on three rivers (Actopan, Antigua, and Blanco) in Mexico. We used optimization of resistance surface methods to determine whether genetic distances between populations are correlated with landscape features.
Results
Positive FIS values evidenced biparental inbreeding in some populations, particularly at higher elevations where lower niche availability constrains colonization and persistence. Four genetic groups were distinguished, corresponding to populations on the Actopan and Antigua rivers and upstream and downstream on the Blanco, but with high admixture between populations on the Actopan and Antigua rivers. Higher gene flow rates were found among proximate populations on the same river than among different rivers. Genetic diversity increased toward the river mouths, in support of the DIGD hypothesis, probably due to greater niche availability and larger population size. Differences among rivers in precipitation patterns and salinity, as well as geographic distance, were significant predictors of gene flow.
Conclusions
Our results depict that the DIGD and gene flow patterns in S. humboldtiana result from the complex interaction among physiography, climate, river salinity, and life‐history traits of the species.
The glycoprotein of Ebola virus (EBOV GP), a member of the family Filoviridae, facilitates viral entry into target cells. In addition, EBOV GP antagonizes the antiviral activity of the host cell ...protein tetherin, which may otherwise restrict EBOV release from infected cells. However, it is unclear how EBOV GP antagonizes tetherin, and it is unknown whether the GP of Lloviu virus (LLOV), a filovirus found in dead bats in Northern Spain, also counteracts tetherin. Here, we show that LLOV GP antagonizes tetherin, indicating that tetherin may not impede LLOV spread in human cells. Moreover, we demonstrate that appropriate processing of N-glycans in tetherin/GP-coexpressing cells is required for tetherin counteraction by EBOV GP. Furthermore, we show that an intact receptor-binding domain (RBD) in the GP1 subunit of EBOV GP is a prerequisite for tetherin counteraction. In contrast, blockade of Niemann-Pick disease type C1 (NPC1), a cellular binding partner of the RBD, did not interfere with tetherin antagonism. Finally, we provide evidence that an antibody directed against GP1, which protects mice from a lethal EBOV challenge, may block GP-dependent tetherin antagonism. Our data, in conjunction with previous reports, indicate that tetherin antagonism is conserved among the GPs of all known filoviruses and demonstrate that the GP1 subunit of EBOV GP plays a central role in tetherin antagonism.
Filoviruses are reemerging pathogens that constitute a public health threat. Understanding how Ebola virus (EBOV), a highly pathogenic filovirus responsible for the 2013-2016 Ebola virus disease epidemic in western Africa, counteracts antiviral effectors of the innate immune system might help to define novel targets for antiviral intervention. Similarly, determining whether Lloviu virus (LLOV), a filovirus detected in bats in northern Spain, is inhibited by innate antiviral effectors in human cells might help to determine whether the virus constitutes a threat to humans. The present study shows that LLOV, like EBOV, counteracts the antiviral effector protein tetherin via its glycoprotein (GP), suggesting that tetherin does not pose a defense against LLOV spread in humans. Moreover, our work identifies the GP1 subunit of EBOV GP, in particular an intact receptor-binding domain, as critical for tetherin counteraction and provides evidence that antibodies directed against GP1 can interfere with tetherin counteraction.
Aim
To infer the geological and climatic factors that have shaped the genetic diversity and structure of a willow species (Salix humboldtiana) in three basins of Central Mexico.
Location
Central ...Mexico.
Methods
We collected samples from 11 populations across two hydrological basins (Balsas and Lerma) and one population from another basin (Ameca) within the Mexican Central Plateau (MCP). Individuals were analyzed using sequences of two chloroplast DNA (cpDNA) regions and eight nuclear simple sequence repeats (nSSR). Population genetic diversity and structure were determined from these data. To evaluate whether genetic structure was associated with ecological niche differentiation, we determined whether there is niche equivalence, overlap, or divergence between the Balsas and Lerma basins. Also, we evaluated the relative contributions of geographic distribution and climatic variation on population genetic structuring through redundancy analysis (RDA) and partial RDA.
Results
Both cpDNA and nSSRs data indicated the presence of three highly differentiated genetic groups, mostly geographically congruent with the three main hydrological basins. According to nSSRs, the three genetic groups can be further subdivided into eight subgroups corresponding to different rivers within the main basins. The niche equivalency test showed that the niches of the species in the Balsas and Lerma basins are significantly nonequivalent. The RDA indicated a significant association of genetic variation among populations with climate variables (particularly those related to the precipitation regime), while controlling for geographic distribution.
Main conclusions
The genetic structure of S. humboldtiana is strongly associated with the historical and current geological configuration of the basins and the rivers within basins. The observed hierarchical genetic differentiation can be due to gene flow limitation resulting from physical barriers to the dispersal of S. humboldtiana, but also to some degree of isolation by environment, as suggested by the significant association between genetic variation among populations and precipitation regime.
The geological and climatological factors that have shaped the genetic diversity and structure of a willow species (Salix humboldtiana) in three basins of Central Mexico were studied. It was found that the genetic structure of the species is strongly associated with the current and historical geological configuration of the basins and the rivers within basins. The observed hierarchical genetic differentiation can be due to gene flow limitation resulting from physical barriers to the dispersal of S. humboldtiana, but also to some degree of isolation by environment, as suggested by the ecological niche differentiation between the Lerma and Balsas basins and the significant association between genetic and environmental distances.
UV spectrophotometric measurement is a widely accepted and standardized routine analysis for quantitation of highly purified proteins; however, the reliability of the results strictly depends on the ...accuracy of the employed extinction coefficients. In this work, an experimental estimation of the differential refractive index (dn/dc), based on dry weight measurements, was performed in order to determine accurate extinction coefficients for four biotherapeutic proteins and one synthetic copolymer after separation in a size-exclusion ultra-performance liquid chromatograph coupled to an ultraviolet, multiangle light scattering and refractive index (SE-UPLC-UV-MALS-RI) multidetection system. The results showed small deviations with respect to theoretical values, calculated from the specific amino acid sequences, for all the studied immunoglobulins. Nevertheless, for proteins like etanercept and glatiramer acetate, several considerations, such as glycan content, partial specific volume, polarizability, and higher order structure, should be considered to properly calculate theoretical extinction coefficient values. Herein, these values were assessed with simple approximations. The precision of the experimentally obtained extinction coefficients, and its convergence towards the theoretical values, makes them useful for characterization and comparability exercises. Also, these values provide insight into the absorbance and scattering properties of the evaluated proteins. Overall, this methodology is capable of providing accurate extinction coefficients useful for development studies.
There are no validation studies on patient satisfaction surveys in Spanish that can evaluate a hospital pharmacy drive-thru service.
To develop and apply a pharmacy drive-thru satisfaction survey in ...Spanish during the COVID-19 pandemic with an analysis of the instrument validation.
This was a qualitative study for developing, validating, and measuring patient satisfaction who used the drive-thru pharmacy during the COVID-19 pandemic. Content validity was obtained by a two-round Delphi and patient interview for apparent validity. The questionnaire was administered to 110 patients. The researchers made an item reduction by inter-item and item-total correlation analysis, stability validation by a test–retest, a test of reliability by Cronbach's alpha, and extraction of factors by an exploratory factorial analysis. Likewise, confirmatory factor analysis was developed to obtain a structural equation model based on generating an instrument of two sub-models of latent factors (service and place) with ten observed variables (items).
A questionnaire was developed that relates six observable variables to the latent factor service and four observable variables to the latent factor place which are ten items based on a Likert scale from 1 to 5, obtaining a Cronbach's alpha = 0.901. The mean population satisfaction score was 4.523. The model presented a Root Mean Square Error of Approximation (RMSEA) of 0.026 (0.000–0.098), and standardized beta values greater than 0.2 according to the confirmatory factor analysis. Therefore, the goodness-of-fit of our model is consistent and the instrument of patient satisfaction with the use of drive-thru has been validated. Patient satisfaction had a mean of 4.9 points.
This study developed and validated a reliable scale that evaluates satisfaction in a hospital pharmacy drive-thru service during COVID-19 pandemic that can be applied in other Spanish speaking countries. A great percentage of the patients that were evaluated had good satisfaction.
Macroalgae populations are influenced by various factors that define their spatial and temporal distribution in different habitats and regions. In Mexico, studies addressing the abundance and ...diversity of macroalgae communities related to environmental factors are scarce. The objective is to determine the spatio-temporal variation of the structure of the community of seaweeds in Xpicob and Villamar, Campeche, during three climatic seasons. Sampling took place during each season using transects and quadrants; additionally, the type of substrate, water temperature, transparency, depth, salinity, and dissolved oxygen, were recorded. The total richness was 74 taxa, corresponding to three classes: Phaeophyceae (3), Florideophyceae (36), and Ulvophyceae (35). Filamentous algae dominate in species richness in the intertidal zone at low depths, while fleshy and calcareous algae predominate in number and biomass in the subtidal zone at higher depths (60–200 cm). Twenty-eight species were common to both sites; meanwhile, 46 taxa were exclusive of specific sites, including 13 found exclusively in Xpicob and 33 in Villamar. The most favorable climatic season for the macroalgae located in Xpicob was the winter rain. For the macroalgae community in Villamar, the most favorable climatic season was the dry. These differences are likely attributed to the predominant environmental and physicochemical characteristics of each site.
Despite lockdown measures, intense symptom-based PCR, and antigen testing, the SARS-CoV-2 pandemic spread further. In this open observational study conducted in Lower Saxony, Germany, voluntary ...SARS-CoV-2 PCR tests were performed from April 2020 until June 2021, supported by serum antibody testing to prove whether PCR testing in subjects with none or few symptoms of COVID-19 is a suitable tool to manage the pandemic. In different mobile stations, 4,817 subjects from three different working fields participated in the PCR testing. Serum antibody screening using the SARS-CoV-2 ViraChip IgG (Viramed, Germany) and the Elecsys Anti-SARS-CoV-2 assay (Roche, Germany) was performed alongside virus neutralization testing. Subjects were questioned regarding comorbidities and COVID-19 symptoms. Fifty-one subjects with acute SARS-CoV-2 infection were detected of which 31 subjects did not show any symptoms possibly characteristic for COVID-19. An additional 37 subjects reported a previous SARS-CoV-2 infection (total prevalence 1.82%). Seroconversion was discovered in 58 subjects with known SARS-CoV-2 infection and in 58 subjects that never had a positive PCR test. The latter had a significantly lower Charlson Comorbidity Index, and one third of them were asymptomatic. In 50% of all seroconverted subjects, neutralizing serum antibodies (NAbs) were detectable in parallel to N/S1 (
= 16) or N/S1/S2 antigen specific antibodies (
= 40) against SARS-CoV-2. NAb titers decreased within 100 days after PCR-confirmed SARS-CoV-2 acute infection by at least 2.5-fold. A relatively high rate of subclinical SARS-CoV-2 infections may contribute to the spread of SARS-CoV-2, suggesting that in addition to other intervention strategies, systematic screening of asymptomatic persons by PCR testing may significantly enable better pandemic control.
Within this open observational study, repeated PCR (
> 4,700) and antibody screening (
> 1,600) tests were offered in three different working fields. The study identified 51 subjects with acute SARS-CoV-2 infection and 37 subjects reported to have had a positive PCR test taken externally. Thirty-one of the 51 subjects did not display any symptoms prior to testing. In addition, 58 subjects without PCR-confirmed SARS-CoV-2 infection were identified by seroconversion. Subjects, that had undergone SARS-CoV-2 infection without having noticed, more often had a low grade of immunization with no NAbs, but may have relevantly contributed to the spread of the pandemic. Based on these results, we suggest that both regular PCR and rapid test screening of symptomatic and asymptomatic individuals, specifically within groups or workplaces identifiable as having close quarter contact, thus increased infection transference risk, is necessary to better assess and therefore reduce the spread of a pandemic virus.
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