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Abstract Background Enterohemorrhagic Escherichia coli (EHEC), a group of enteric pathogenic bacteria that is a major cause of human diarrheal disease, must interact with the diverse intestinal microbiome during colonization and subsequently overcome the environmental challenges to survive and cause disease. While this relationship, and how the microbiome modulates infection of EHEC, has been studied, it is less understood how the microbiome is impacted during treatment for an EHEC infection. One area that is notably lacking in knowledge is how vaccination can impact the intestinal microbiome composition, and therefore, influence vaccine efficacy. We previously developed vaccine formulations consisting of gold nanoparticles (AuNPs) conjugated to various EHEC antigens and tested them in mice models using both EHEC and its murine counterpart Citrobacter rodentium. The goal of this study was to evaluate the relationship between these EHEC vaccines and their effects on the gut microbiome. Results We found that immunization with the vaccines or adjuvant-only control did not lead to major alterations in the composition of the fecal microbiome; however, there were measurable variations in individual mice within the same vaccine group housed in separate cages. Also, immunization with one vaccine (AuNP-EscC) prevented both a decrease in the diversity of the fecal microbiome and an increase in detectable C. rodentium following infection compared to control animals. Conclusions Overall, our small study argues in favor of evaluating the intestinal microbiome during vaccine development not just for EHEC, but for other enteric pathogens.

Abstract This paper describes the development of a double-sided band-pass frequency selective surface based on Matryoshka geometry, preserving features such as miniaturization, multiband operation and stability of polarization and angle of incidence. Unlike cascaded FSSs, the proposal uses only one layer of substrate, with Matryoshka geometry on one side and a square mesh on the other, reducing volume and simplifying manufacturing by avoiding spacers. The double-sided FSS allows the frequency response to be adjusted using the geometry of the opposite face, which in this work is a square loop. With an attenuation of -10 dB, the proposed configuration offers a free band from 3.48 GHz to 9.06 GHz, compared to the original configuration, which ranged from 5.88 GHz to 7.43 GHz, with only 1.55 GHz free. Initial design equations are presented which facilitate the creation of FSSs for other frequencies and applications. An FSS has been designed, fabricated, and characterized, with good agreement between numerical and experimental results. The resonant frequency remains practically constant for different incidence angles, from 0º to 60º, confirming the angular stability.

Burkholderia pseudomallei (Bpm) is the causative agent of the disease melioidosis. As a facultative intracellular pathogen, Bpm has a complex lifestyle that culminates in cell-to-cell fusion and multinucleated giant cells (MNGCs) formation. The virulence factor responsible for MNGC formation is the type 6 secretion system (T6SS), a contractile nanomachine. MNGC formation is a cell-to-cell spread strategy that allows the bacteria to avoid the extracellular immune system and our previous data highlighted cell death, apoptosis, and inflammation as pathways significantly impacted by T6SS activity. Thusly, we investigated how the T6SS influences these phenotypes within the macrophage and pulmonary models of infection. Here we report that the T6SS is responsible for exacerbating apoptotic cell death during infection in both macrophages and the lungs of infected mice. We also demonstrate that although the T6SS does not influence differential macrophage polarization, the M2 polarization observed is potentially beneficial for Bpm pathogenesis and replication. Finally, we show that the T6SS contributes to the severity of inflammatory nodule formation in the lungs, which might be potentially connected to the amount of apoptosis that is triggered by the bacteria.

ABSTRACT Burkholderia pseudomallei (Bpm) is a Gram-negative intracellular pathogen that causes melioidosis in humans, a neglected, underreported, and lethal disease that can reach a fatal outcome in over 50% of the cases. It can produce both acute and chronic infections, the latter being particularly challenging to eliminate because of the intracellular life cycle of the bacteria and its ability to generate a “persister” dormant state. The molecular mechanism that allows the switch between growing and persister phenotypes is not well understood but it is hypothesized to be due at least in part to the participation of toxin-antitoxin (TA) systems. We have previously studied the link between one of those systems (defined as HigBA) with specific expression patterns associated with levofloxacin antibiotic exposure. Through in silico methods, we predicted the presence of another three pairs of genes encoding for additional putative HigBA systems. Therefore, our main goal was to establish which mechanisms are conserved as well as which pathways are specific among different Bpm TA systems from the same family. We hypothesize that the high prevalence, and sometimes even redundancy of these systems in the Bpm chromosomes indicates that they can interact with each other and not function as only individual systems, as it was traditionally thought, and might be playing an undefined role in Bpm lifecycle. Here, we show that both the toxin and the antitoxin of the different systems contribute to bacterial survival and that toxins from the same family can have a cumulative effect under environmental stressful conditions.IMPORTANCEToxin-antitoxin (TA) systems play a significant role in bacterial persistence, a phenomenon where bacterial cells enter a dormant or slow-growing state to survive adverse conditions such as nutrient deprivation, antibiotic exposure, or host immune responses. By studying TA systems in Burkholderia pseudomallei, we can gain insights into how this pathogen survives and persists in the host environment, contributing to its virulence and ability to cause melioidosis chronic infections.

Accumulating evidence suggests that hyperuricemia is a pathological factor in the development and progression of chronic kidney disease. However, the potential benefit afforded by the control of uric acid (UA) is controversial. Individual studies show discrepant results, and most existing meta-analysis, especially those including the larger number of studies, lack a placebo or control group as they aim to compare efficacy between drugs. On these grounds, we performed a me-ta-analysis restricted to studies including the action of any anti-gout therapies referenced to a control or placebo arm. This approach allows for a clearer association between UA reduction and renal effect. Of the twenty-nine papers included, most used allopurinol and febuxostat and, therefore, solid conclusions could only be obtained for these drugs. Both were very effective in reducing UA, but only allopurinol was able to significantly improve glomerular filtration rate (GFR), although not in a dose-dependent manner. These results raised doubts as to whether it is the hypouricemic effect of anti-gout drugs, or a pleiotropic effect, what provides protection of kidney function. Accordingly, in a correlation study that we next performed between UA reduction and GFR improvement, no association was found, which suggests that additional mechanisms may be involved. Of note, most trials show large inter-individual response variability, probably because they included patients with heterogeneous phenotypes and pathological characteristics, including different stages of CKD and comorbidities. This highlights the need to sub classify the effect of UA-lowering therapies according to the pathological scenario, in order to identify those CKD patients that may benefit most from them.Systematic Review Registration: CRD42022306646 https://www.crd.york.ac.uk/prospero/

ABSTRACT Enterohemorrhagic Escherichia coli (EHEC) is a group of pathogenic bacteria responsible for several foodborne-associated outbreaks of human diarrheal disease. Although EHEC is a major cause of morbidity as well as the condition known as hemolytic uremic syndrome, linked to the production of Shiga toxins (Stx), there are no licensed vaccines approved for human use. Fully assessing vaccine efficacy against EHEC infections is challenging because conventional adult mice are inherently resistant to EHEC infection and do not develop hallmark symptoms of the disease. Therefore, in this study, we utilized a strain of the murine pathogen Citrobacter rodentium that has been lysogenized to produce Stx2d, which consistently causes lethal infection and other measurable disease outcomes following oral challenge, to further evaluate the protective efficacy of our previously formulated EHEC gold nanoparticle (AuNP) vaccines. Using this model, along with a non-Stx2d-producing C. rodentium strain, we assessed the protection conferred by AuNPs conjugated to three EHEC antigens: EscC, LomW, and intimin (Eae). We demonstrated that intranasally immunizing mice with AuNP-Eae provides partial protection against mortality caused by Stx2d-producing C. rodentium and that AuNP-EscC and AuNP-Eae moderately reduce intestinal burden of the non-Stx2d-producing C. rodentium strain compared with adjuvant-only-treated mice. Additionally, the AuNP-protein vaccines induced antigen- and pathogen-specific serum IgG and fecal IgA against both EHEC and C. rodentium while in vitro functional assays indicate that the elicited antibodies are bactericidal and prevent adherence of C. rodentium to intestinal epithelial cells. We propose that C. rodentium murine data could translate into correlates of protection. IMPORTANCE Enterohemorrhagic Escherichia coli (EHEC) remains an important cause of diarrheal disease and complications worldwide, especially in children, yet there are no available vaccines for human use. Inadequate pre-clinical evaluation due to inconsistent animal models remains a major barrier to novel vaccine development. We demonstrate the usefulness of Stx2d-producing Citrobacter rodentium in assessing vaccine effectiveness because it more closely recapitulates human disease caused by EHEC.

ABSTRACT Burkholderia pseudomallei (Bpm) is the causative agent of melioidosis disease. Bpm is a facultative intracellular pathogen with a complex life cycle inside host cells. Pathogenic success depends on a variety of virulence factors with one of the most critical being the type 6 secretion system (T6SS). Bpm uses the T6SS to move into neighboring cells, resulting in multinucleated giant cell (MNGC) formation, a strategy used to disseminate from cell to cell. Our prior study using a dual RNA-seq analysis to dissect T6SS-mediated virulence on intestinal epithelial cells identified BicA as a factor upregulated in a T6SS mutant. BicA regulates both type 3 secretion system (T3SS) and T6SSs; however, the extent of its involvement during disease progression is unclear. To fully dissect the role of BicA during systemic infection, we used two macrophage cell lines paired with a pulmonary in vivo challenge murine model. We found that ΔbicA has a distinct intracellular replication defect in both immortalized and primary macrophages, which begins as early as 1 h post-infection. This intracellular defect is linked with the lack of cell-to-cell dissemination and MNGC formation as well as a defect in T3SS expression. The in vitro phenotype translated in vivo as ΔbicA was attenuated in a pulmonary model of infection, demonstrating a distinct macrophage activation profile and a lack of pathological features present in the wild type. Overall, these results highlight the role of BicA in regulating intracellular virulence and demonstrate that specific regulation of secretion systems has a significant effect on host response and Bpm pathogenesis. IMPORTANCE Melioidosis is an understudied tropical disease that still results in ~50% fatalities in infected patients. It is caused by the Gram-negative bacillus Burkholderia pseudomallei (Bpm). Bpm is an intracellular pathogen that disseminates from the infected cell to target organs, causing disseminated disease. The regulation of secretion systems involved in entry and cell-to-cell spread is poorly understood. In this work, we characterize the role of BicA as a regulator of secretion systems during infection of macrophages in vitro and in vivo. Understanding how these virulence factors are controlled will help us determine their influence on the host cells and define the macrophage responses associated with bacterial clearance.

Enterohemorrhagic E. coli (EHEC) is a group of pathogenic bacteria that is associated with worldwide human foodborne diarrheal illnesses and the development of hemolytic uremic syndrome, a potentially deadly condition associated with Shiga toxins (Stxs). Currently, approved vaccines for human prophylaxis against infection do not exist, and one barrier preventing the successful creation of EHEC vaccines is the absence of dependable animal models, including mice, which are naturally resistant to EHEC infection and do not manifest the characteristic signs of the illness. Our lab previously developed gold nanoparticle (AuNP)-based EHEC vaccines, and assessed their efficacy using Citrobacter rodentium, which is the mouse pathogen counterpart of EHEC, along with an Stx2d-producing strain that leads to more consistent disease kinetics in mice, including lethality. The purpose of this study was to continue evaluating these vaccines to increase protection. Here, we demonstrated that subcutaneous immunization of mice with AuNPs linked to the EHEC antigens EscC and intimin (Eae), either alone or simultaneously, elicits functional robust systemic humoral responses. Additionally, vaccination with both antigens together showed some efficacy against Stx2d-producing C. rodentium while AuNP-EscC successfully limited infection with non-Stx2d-producing C. rodentium. Overall, the collected results indicate that our AuNP vaccines have promising potential for preventing disease with EHEC, and that evaluation of novel vaccines using an appropriate animal model, like C. rodentium described here, could be the key to finally developing an effective EHEC vaccine that can progress into human clinical trials.

While conducting recombinant DNA technology procedures, such as DNA purification, agarose gel electrophoresis is often used for identification, characterization and quantification of DNA. The collection of data for experiments involving such techniques frequently involves capturing images using systems that are expensive and/or proprietary, such that they are not user-serviceable when they malfunction or become antiquated. In response to these limitations, work was done to replace the authors' existing aging Mac OS-based modular system with open-source software and generic hardware. Several versions of a modular imaging system that can be adjusted to fit nearly all use cases are described. The systems developed can accommodate diverse uses from research laboratories to educational environments where commercial systems could be unaffordable.

Recently, the pathogen that causes melioidosis, Burkholderia pseudomallei, was found in the Gulf Coast region of Mississippi, United States of America, associated with human cases and as bacteria in the soil of affected areas. Therefore, the Centers for Disease Control and Prevention has declared the pathogen as endemic in the continental United States for the first time. This viewpoint discusses some issues that the research, public health communities, and government agencies need to address.

Burkholderia are a group of Gram-negative bacteria that can cause a variety of diseases in at-risk populations. B. pseudomallei and B. mallei, the etiological agents of melioidosis and glanders, respectively, are the two clinically relevant members of the B. pseudomallei complex (Bpc). The development of vaccines against Bpc species has been accelerated in recent years, resulting in numerous promising subunits and glycoconjugate vaccines incorporating a variety of antigens. However, a second group of pathogenic Burkholderia species exists known as the Burkholderia cepacia complex (Bcc), a group of opportunistic bacteria which tend to affect individuals with weakened immunity or cystic fibrosis. To date, there have been few attempts to develop vaccines to Bcc species. Therefore, the primary goal of this review is to provide a broad overview of the various subunit antigens that have been tested in Bpc species, their protective efficacy, study limitations, and known or suspected mechanisms of protection. Then, we assess the reviewed Bpc antigens for their amino acid sequence conservation to homologous proteins found in Bcc species. We propose that protective Bpc antigens with a high degree of Bpc-to-Bcc sequence conservation could serve as components of a pan-Burkholderia vaccine capable of protecting against both disease-causing groups.

Melioidosis is a disease caused by the Gram-negative bacillus Burkholderia pseudomallei (Bpm), commonly found in soil and water of endemic areas. Naturally acquired human melioidosis infections can result from either exposure through percutaneous inoculation, inhalation, or ingestion of soil-contaminated food or water. Our prior studies recognized Bpm as an effective enteric pathogen, capable of establishing acute or chronic gastrointestinal infections following oral inoculation. However, the specific mechanisms and virulence factors involved in the pathogenesis of Bpm during intestinal infection are unknown. In our current study, we standardized an in vitro intestinal infection model using primary intestinal epithelial cells (IECs) and demonstrated that Bpm requires a functional T6SS for full virulence. Further, we performed dual RNA-seq analysis on Bpm-infected IECs to evaluate differentially expressed host and bacterial genes in the presence or absence of a T6SS. Our results showed a dysregulation in the TNF-α signaling via NF-κB pathway in the absence of the T6SS, with some of the genes involved in inflammatory processes and cell death also affected. Analysis of the bacterial transcriptome identified virulence factors and regulatory proteins playing a role during infection, with association to the T6SS. By using a Bpm transposon mutant library and isogenic mutants, we showed that deletion of the bicA gene, encoding a putative T3SS/T6SS regulator, ablated intracellular survival and plaque formation by Bpm and impacted survival and virulence when using murine models of acute and chronic gastrointestinal infection. Overall, these results highlight the importance of the type 6 secretion system in the gastrointestinal pathogenesis of Bpm.

Abstract Critical thermal limits (CTmax and CTmin) decrease with elevation, with greater change in CTmin, and the risk to suffer heat and cold stress increasing at the gradient ends. A central prediction is that populations will adapt to the prevailing climatic conditions. Yet, reliable support for such expectation is scant because of the complexity of integrating phenotypic, molecular divergence and organism exposure. We examined intraspecific variation of CTmax and CTmin, neutral variation for 11 microsatellite loci, and micro‐ and macro‐temperatures in larvae from 11 populations of the Galician common frog (Rana parvipalmata) across an elevational gradient, to assess (1) the existence of local adaptation through a PST‐FST comparison, (2) the acclimation scope in both thermal limits, and (3) the vulnerability to suffer acute heat and cold thermal stress, measured at both macro‐ and microclimatic scales. Our study revealed significant microgeographic variation in CTmax and CTmin, and unexpected elevation gradients in pond temperatures. However, variation in CTmax and CTmin could not be attributed to selection because critical thermal limits were not correlated to elevation or temperatures. Differences in breeding phenology among populations resulted in exposure to higher and more variable temperatures at mid and high elevations. Accordingly, mid‐ and high‐elevation populations had higher CTmax and CTmin plasticities than lowland populations, but not more extreme CTmax and CTmin. Thus, our results support the prediction that plasticity and phenological shifts may hinder local adaptation, promoting thermal niche conservatism. This may simply be a consequence of a coupled variation of reproductive timing with elevation (the “elevation‐time axis” for temperature variation). Mid and high mountain populations of R. parvipalmata are more vulnerable to heat and cool impacts than lowland populations during the aquatic phase. All of this contradicts some of the existing predictions on adaptive thermal clines and vulnerability to climate change in elevational gradients.

In recent years, immunotherapy has been postulated as one of the most effective strategies in the fight against cancer. The greatest success in this field has been achieved with the inhibition of molecules involved in slowing down the adaptive immune response by immune checkpoint inhibitors (ICIs). Despite its efficacy, ICI treatment has side effects. Regarding kidney damage, it is estimated that 4.9% of patients treated with ICIs develop renal injury. Furthermore, cancer patients who develop renal dysfunction have a worse prognosis. Current diagnostics are insufficient to predict the underlying renal injury and to identify the type of damage. Our hypothesis is that the renal injury could be subclinical, so the possibility of using new urinary biomarkers could be a useful diagnostic tool that would allow these patients to be managed in a preventive (risk biomarkers) and early (early biomarkers) way and even to clarify whether the renal damage is due to this therapy or to other factors (differential diagnostic biomarkers). A prospective study to validate risk and early and differential biomarkers in patients treated with ICIs is proposed to test this hypothesis. The results derived from this study will improve the clinical practice of cancer treatment with ICIs and therefore the life expectancy and quality of life of patients. Trial Registration: ClinicalTrials.gov, NCT04902846.

Abstract Melioidosis, caused by Burkholderia pseudomallei (Bpm), lacks a vaccine. We identify the immune correlates of protection induced by B. mallei ΔtonB Δhcp1 (CLH001) and Bpm ΔtonB Δhcp1 (PBK001) vaccines against inhalational melioidosis. Mucosal immunization with either vaccine generates Bpm-specific IgM and IgG (IgG2 b/c > IgG1 > IgG3) antibodies in sera and lungs, and lung IgA antibodies. Sera confers complement-independent bactericidal activity and macrophages opsonophagocytic uptake but is insufficient in passive transfer experiments to provide significant protection. Both vaccines elicit memory Th1 and Th17 CD4+ T-cell responses in lung and spleen after Bpm antigen-specific recall. The PBK001 vaccine is superior in generating respiratory IgA post-boost, anamnestic IgG at challenge, T-cell recall to specific antigen, and development of diverse polyfunctional memory T-cell pools. Analysis of lung histology suggests that potent polyfunctional T-cell memory and/or IL-17 signatures generated with PBK001 vaccination may be associated with moderate lung inflammation post vaccination.

ABSTRACT The Latin American Coalition for Escherichia coli Research (LACER) was created as a network of investigators using One Health approaches trying to understand infections caused by regional E. coli isolates and to sound the alarm due to the evolution of strains that are multiresistant to antibiotics (resistome) that also display different virulence profiles (virulome). After the COVID19 pandemic, a major concern by investigators has been the appearance of more virulent and resistant strains. Recently, a paper published in Microbiology Spectrum by Brazilian investigators (Fuga B., et al. Microbiol Spectr 10:e0125621, 2022, https://doi.org/10.1128/spectrum.01256-21) has used a genomic approach to demonstrate that during a period of 45 years, a wide resistome and virulome has converged, resulting in the appearance and persistence of high-risk clones affecting humans, animals and the environment, and its rapid dissemination is becoming an unattended international threat.

Prophylactic trimethoprim/sulfamethoxazole (TMP/SMX) prevents Pneumocystis jirovecii pneumonia and nocardiosis in immunocompromised patients but sometimes is avoided because of purported allergies or side effects. Of 25 immunocompromised patients receiving alternative prophylaxis in whom nocardiosis developed, 16 subsequently tolerated TMP/SMX treatment. Clinicians should consider TMP/SMX allergy evaluation and rechallenging to assess patient tolerance.

Abstract Effective management of exploited populations is based on an understanding of population dynamics and evolutionary processes. In spatially structured populations, dispersal is a central process that ultimately can affect population growth and viability. It can be influenced by environmental conditions, individual phenotypes, and stochastic factors. However, we have a limited knowledge of the relative contribution of these components and its interactions, and which traits can be used as reliable predictors of the dispersal ability. Here, we conducted a longitudinal field experiment aimed to identify traits which can be used as proxy for dispersal in juvenile brown trout (Salmo trutta L.). We measured body size and standard metabolic rates, and estimated body shapes for 212 hatchery-reared juvenile fish that were marked with individual codes and released in a small coastal stream in northwest Spain. We registered fish positions and distances to the releasing point after 19, 41, 60 and 158 days in the stream. We detected a high autocorrelation of dispersal distances, demonstrating that most individuals settle down relatively soon and then hold stable positions over the study period. Body size and fish shape were reliable predictors of dispersal, with bigger and more robust-set individuals being more likely to settle closer to the release site than smaller and more elongated fish. In addition, the analysis of spacing and spatial patterns indicated that the dispersal of introduced fish could affect the distribution of resident conspecifics. All together, these results suggest that stocking programs aimed to the enhancement of overexploited populations at fine spatial scales can be optimized by adjusting the size and shape of the introduced fish to specific management targets and environmental conditions.

We report an analysis of the genomic diversity of isolates of Burkholderia pseudomallei, the cause of melioidosis, recovered in Colombia from routine surveillance during 2016–2017. B. pseudomallei appears genetically diverse, suggesting it is well established and has spread across the region.

Abstract Background Melioidosis is an infectious disease caused by Burkholderia pseudomallei. In Mexico, the disease is rarely diagnosed in humans and there is no evidence of simultaneous environmental isolation of the pathogen. Here, we describe clinical profiles of fatal cases of melioidosis in two children, in a region without history of that disease. Case presentation About 48 h before onset of symptoms, patients swam in a natural body of water, and thereafter they rapidly developed fatal septicemic illness. Upon necropsy, samples from liver, spleen, lung, cerebrospinal fluid, and bronchial aspirate tissues contained Burkholderia pseudomallei. Environmental samples collected from the locations where the children swam also contained B. pseudomallei. All the clinical and environmental strains showed the same BOX-PCR pattern, suggesting that infection originated from the area where the patients were swimming. Conclusions The identification of B. pseudomallei confirmed that melioidosis disease exists in Sonora, Mexico. The presence of B. pseudomallei in the environment may suggest endemicity of the pathogen in the region. This study highlights the importance of strengthening laboratory capacity to prevent and control future melioidosis cases.

Abstract Background Incarceration is disruptive to HIV care, often resulting in poor retention in care for people living with HIV (PLWH) after jail release. This gap in HIV care might result in potentially preventable emergency department (ED) utilization. We analyzed demographic, incarceration, socioeconomic and clinical data for PLWH released from the Dallas County Jail to the community (1450 incarcerations, 1155 unique individuals) between January 2011 and November 2013. Results The study population consisted of predominantly men (77%), with a mean age of 39 years, 67% were black and 14% were Hispanic; half of the releasees visited the ED at least once during the first-year post-jail. In adjusted analyses, female gender, family awareness of HIV status, serious mental illness, and late engagement to HIV care were significantly associated with higher ED utilization. Compared to the general Dallas population, PLWH released from jail had a 5-fold higher proportion of ED visits classified as related to substance use or mental health. Conclusions Further efforts are needed to improve the transition from incarceration to community-based HIV care, substance use disorder treatment and mental health services, and to directly address re-engagement in HIV care for out-of-care PLWH who visit the ED.

Summary: Background: COH04S1, a synthetic attenuated modified vaccinia virus Ankara vector co-expressing SARS-CoV-2 spike and nucleocapsid antigens, was tested for safety and immunogenicity in healthy adults. Methods: This combined open-label and randomised, phase 1 trial was done at the City of Hope Comprehensive Cancer Center (Duarte, CA, USA). We included participants aged 18–54 years with a negative SARS-CoV-2 antibody and PCR test, normal haematology and chemistry panels, a normal electrocardiogram and troponin concentration, negative pregnancy test if female, body-mass index of 30 kg/m2 or less, and no modified vaccinia virus Ankara or poxvirus vaccine in the past 12 months. In the open-label cohort, 1·0 × 107 plaque-forming units (PFU; low dose), 1·0 × 108 PFU (medium dose), and 2·5 × 108 PFU (high dose) of COH04S1 were administered by intramuscular injection on day 0 and 28 to sentinel participants using a queue-based statistical design to limit risk. In a randomised dose expansion cohort, additional participants were randomly assigned (3:3:1), using block size of seven, to receive two placebo vaccines (placebo group), one low-dose COH04S1 and one placebo vaccine (low-dose COH04S1 plus placebo group), or two low-dose COH04S1 vaccines (low-dose COH04S1 group). The primary outcome was safety and tolerability, with secondary objectives assessing vaccine-specific immunogenicity. The primary immunological outcome was a four times increase (seroconversion) from baseline in spike-specific or nucleocapsid-specific IgG titres within 28 days of the last injection, and seroconversion rates were compared with participants who received placebo using Fisher's exact test. Additional secondary outcomes included assessment of viral neutralisation and cellular responses. This trial is registered with ClinicalTrials.gov, NCT046339466. Findings: Between Dec 13, 2020, and May 24, 2021, 56 participants initiated vaccination. On day 0 and 28, 17 participants received low-dose COH04S1, eight received medium-dose COH04S1, nine received high-dose COH04S1, five received placebo, 13 received low-dose COH04S1 followed by placebo, and four discontinued early. Grade 3 fever was observed in one participant who received low-dose COH04S1 and placebo, and grade 2 anxiety or fatigue was seen in one participant who received medium-dose COH04S1. No severe adverse events were reported. Seroconversion was observed in all 34 participants for spike protein and 32 (94%) for nucleocapsid protein (p

Histoplasmosis-associated hemophagocytic lymphohistiocytosis is a rate but lethal disease in immunocompromised hosts. Unusual clinical presentations make diagnosing invasive fungal infection even more challenging. Here we present a case of hemophagocytic lymphohistiocytosis secondary to progressive disseminated histoplasmosis presenting as cellulitis in a patient with systemic lupus erythematous. A high index of suspicion combined with histopathology and molecular diagnostic techniques are important to establish an accurate and timely diagnosis of opportunistic infections in immunocompromised patients.

Axillary artery injury after a shoulder dislocation is an extremely rare condition. Open surgery is the classical treat- ment of such lesions, consisting of direct suture at the site of the rupture or arterial reconstruction with a patch or a bypass. We report the case of a 74-years-old man who suffered a vascular and neurological injury after a recurrent glenohumeral joint dislocation and was treated with a covered stent.

ABSTRACT Enterohemorrhagic Escherichia coli (EHEC) O157:H7 remains a pathogen of significance and high consequence around the world. This outcome is due in part to the high economic impact associated with massive, contaminated product recalls, prevalence of the pathogen in carrier reservoirs, disease sequelae, and mortality associated with several outbreaks worldwide. Furthermore, the contraindication of antibiotic use for the treatment of EHEC-related infections makes this pathogen a primary candidate for the development of effective prophylactic vaccines. However, no vaccines are approved for human use, and many have failed to provide a high degree of efficacy or broad protection, thereby opening an avenue for the use of new technologies to produce a safe, effective, and protective vaccine. Building on our previous studies using reverse vaccinology-predicted antigens, we refine a formulation, evaluate new immunogenic antigens, and further expand our understanding about the mechanism of EHEC vaccine-mediated protection. In the current study, we exploit the use of the nanotechnology platform based on gold nanoparticles (AuNP), which can act as a scaffold for the delivery of various antigens. Our results demonstrate that a refined vaccine formulation incorporating EHEC antigen LomW, EscC, LpfA1, or LpfA2 and delivered using AuNPs can elicit robust antigen-specific cellular and humoral responses associated with reduced EHEC colonization in vivo. Furthermore, our in vitro mechanistic studies further support that antibody-mediated protection is primarily driven by inhibition of bacterial adherence onto intestinal epithelial cells and by promotion of macrophage uptake and killing. IMPORTANCE Enterohemorrhagic E. coli O157:H7 remains an important human pathogen that does not have an effective and safe vaccine available. We have made outstanding progress in the identification of novel protective antigens that have been incorporated into the gold nanoparticle platform and used as vaccines. In this study, we have refined our vaccine formulations to incorporate multiple antigens and further define the mechanism of antibody-mediated protection, including one vaccine that promotes macrophage uptake. We further define the cell-mediated responses elicited at the mucosal surface by our nanovaccine formulations, another key immune mechanism linked to protection.

The way that diversity, equity, and inclusion impact scientific careers varies for everyone, but it is evident that institutions providing an environment where being different or having differences creates a sense of being welcomed, supported, and valued are beneficial to the scientific community at large. In this commentary, three short stories from Texas-based microbiologists are used to depict (i) the importance of bringing the guiding principles of diversity, equity, and inclusion within their professional roles, (ii) the need to apply and translate those principles to support and enable successful scientific careers among peers and trainees, and (iii) the impact of effective science communication to increase the understanding of microbial environments among the community at large.

We can learn from the diversity of microbial communities, represented by the thriving of different species. Failure to build inclusive microbial sciences only perpetuates an imbalance that is damaging to the scientific community. As microbiologists, are we ready to lead the way on diversity and inclusion initiatives and set an example for the rest of the professions and scientific fields?

Melioidosis is a complex human disease associated with a wide range of complications caused by the Gram-negative bacillus Burkholderia pseudomallei

The evolutionary forces that favour transitions in sex chromosomes are not well understood. Here, Jeffries and colleagues show a very high rate of sex chromosome turnover in true frogs, which may be driven by rapid mutation-load accumulation due to the low recombination rate in males.

El objetivo del estudio fue describir las características clínicas de pacientes con enfermedad pulmonar obstructiva crónica (EPOC), atendidos en los servicios de Neumología de centros especializados de Lima y Callao. Se realizó un estudio transversal en 196 pacientes, con una mediana de edad de 69 años, rango intercuartil 63-75 años. El 31,1 % de los pacientes se encontró en el grupo GOLD 1/leve (VEF1 ≥80 %), el 41,8 % en el grupo GOLD 2/moderado (50 %≤VEF180 %), el 22,5 % en el grupo GOLD 3/severo (30 %≤VEF150 %), y el 4,6 % en el grupo GOLD 4/muy severo (VEF1 30 %). El 93,9 % usaba algún tipo de medicación para EPOC, la terapia más usada fue la combinación de beta agonistas de acción larga/corticoides inhalados (LABA/ICS) con 31,1 %. Se ha obtenido una primera caracterización de pacientes con EPOC atendidos en estos centros. Es imprescindible complementar lo encontrado con estudios longitudinales.

Glomerular filtration is a pivotal process of renal physiology, and its alterations are a central pathological event in acute kidney injury and chronic kidney disease. Creatinine clearance (ClCr), a standard method for glomerular filtration rate (GFR) measurement, requires a long and tedious procedure of timed (usually 24 h) urine collection. We have developed a neural network (NN)-based calculator of rat ClCr from plasma creatinine (pCr) and body weight. For this purpose, matched pCr, weight, and ClCr trios from our historical records on male Wistar rats were used. When evaluated on the training (1165 trios), validation (389), and test sets (660), the model committed an average prediction error of 0.196, 0.178, and 0.203 mL/min and had a correlation coefficient of 0.863, 0.902, and 0.856, respectively. More importantly, for all datasets, the NN seemed especially effective at comparing ClCr among groups within individual experiments, providing results that were often more congruent than those measured experimentally. ACLARA, a friendly interface for this calculator, has been made publicly available to ease and expedite experimental procedures and to enhance animal welfare in alignment with the 3Rs principles by avoiding unnecessary stressing metabolic caging for individual urine collection.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological agent responsible for the coronavirus disease 2019 (COVID-19). The high rate of mutation of this virus is associated with a quick emergence of new viral variants that have been rapidly spreading worldwide. Several mutations have been documented in the receptor-binding domain (RBD) of the viral spike protein that increases the interaction between SARS-CoV-2 and its cellular receptor, the angiotensin-converting enzyme 2 (ACE2). Mutations in the spike can increase the viral spread rate, disease severity, and the ability of the virus to evade either the immune protective responses, monoclonal antibody treatments, or the efficacy of current licensed vaccines. This review aimed to highlight the functional virus classification used by the World Health Organization (WHO), Phylogenetic Assignment of Named Global Outbreak (PANGO), Global Initiative on Sharing All Influenza Data (GISAID), and Nextstrain, an open-source project to harness the scientific and public health potential of pathogen genome data, the chronological emergence of viral variants of concern (VOCs) and variants of interest (VOIs), the major findings related to the rate of spread, and the mutations in the spike protein that are involved in the evasion of the host immune responses elicited by prior SARS-CoV-2 infections and by the protection induced by vaccination.

Quercetin, a flavonoid with promising therapeutic potential, has been shown to protect from cisplatin nephrotoxicity in rats following intraperitoneal injection, but its low bioavailability curtails its prospective clinical utility in oral therapy. We recently developed a micellar formulation (P-quercetin) with enhanced solubility and bioavailability, and identical nephroprotective properties. As a first aim, we herein evaluated the oral treatment with P-quercetin in rats, which displayed no nephroprotection. In order to unravel this discrepancy, quercetin and its main metabolites were measured by HPLC in the blood and urine after intraperitoneal and oral administrations. Whilst quercetin was absorbed similarly, the profile of its metabolites was different, which led us to hypothesize that nephroprotection might be exerted in vivo by a metabolic derivate. Consequently, we then aimed to evaluate the cytoprotective capacity of quercetin and its main metabolites (quercetin 3-O-glucoside, rutin, tamarixetin, isorhamnetin and quercetin 3-O-glucuronide) against cisplatin toxicity, in HK-2 and NRK-52E tubular cell lines. Cells were incubated for 6 h with quercetin, its metabolites or vehicle (pretreatment), and subsequently 18 h in cotreatment with 10–300 μM cisplatin. Immediately after treatment, cell cultures were subject to the MTT technique as an index of cytotoxicity and photographed under light microscopy for phenotypic assessment. Quercetin afforded no direct cytoprotection and quercetin-3-O-glucuronide was the only metabolite partially preventing the effect of cisplatin in cultured tubule cells. Our results identify a metabolic derivative of quercetin contributing to its nephroprotection and prompt to further explore exogenous quercetin-3-O-glucuronide in the prophylaxis of tubular nephrotoxicity.

Asparaginase (ASNase) is a widely applied chemotherapeutic drug that is used to treat Acute Lymphoblastic Leukemia (ALL); however, immune responses and silent inactivation of the drug often limit its bioavailability. Many strategies have been proposed to overcome these drawbacks, including the development of improved formulations (biobetters), but only two of them are currently on the market. Nano- and micro-encapsulation are some of the most promising and novel approaches to enhance in vivo performance of ASNase, preventing the direct contact of the enzyme with the environment, protecting it from protease degradation, increasing the enzymes catalytic half-life, and in some cases, reducing immunogenicity. This review summarizes the strategies, particularly for ASNase nano- and micro-encapsulation, and their main findings, constraints, and current gaps in the state-of-the-art knowledge. The pros and cons of the use of different nanocarriers are discussed with the idea to ultimately provide safer and more effective treatments for patients with ALL.

Chronic kidney disease (CKD) is a progressive impairment of renal function for more than three months that affects 15% of the adult population. Because oxidative stress is involved in its pathogenesis, antioxidants are under study for the prophylaxis of CKD progression. The objective of this work was to meta-analyze the efficacy of antioxidant therapy in CKD patients and to identify the most effective candidate antioxidants. Our meta-analysis showed that, despite being quite heterogeneous, overall antioxidant therapy apparently reduced CKD progression. Pentoxifylline and bardoxolone methyl demonstrated a robust and statistically significant protection, while other products showed a favorable but non-significant tendency, due to a high interindividual variability. Off-target (i.e., antioxidant-independent) effects, such as body weight reduction and heart failure-associated blood dilution, might totally or partially explain the protection provided by effective antioxidants. This potential pleiotropy introduces uncertainty on the role of oxidative stress in CKD progression and on antioxidant therapy in its prevention, which needs to be further investigated. Independently, identification of factors determining the nephroprotective effect of each candidate on each patient is thus necessary for a prospectively personalized antioxidant therapy. Finally, pentoxifylline should be further explored for the prophylaxis of CKD progression.

Significant advancement has been made in the development of vaccines against bacterial pathogens. However, several roadblocks have been found during the evaluation of vaccines against intracellular bacterial pathogens. Therefore, new lessons could be learned from different vaccines developed against unrelated intracellular pathogens. Bacillary dysentery and melioidosis are important causes of morbidity and mortality in developing nations, which are caused by the intracellular bacteria Shigella and Burkholderia pseudomallei, respectively. Although the mechanisms of bacterial infection, dissemination, and route of infection do not provide clues about the commonalities of the pathogenic infectious processes of these bacteria, a wide variety of vaccine platforms recently evaluated suggest that in addition to the stimulation of antibodies, identifying protective antigens and inducing T cell responses are some additional required elements to induce effective protection. In this review, we perform a comparative evaluation of recent candidate vaccines used to combat these two infectious agents, emphasizing the common strategies that can help investigators advance effective and protective vaccines to clinical trials.

Mg doping of GaAs nanowires has been established as a viable alternative to Be doping in order to achieve p-type electrical conductivity. Although reports on the optical properties are available, few reports exist about the physical properties of intermediate-to-high Mg doping in GaAs nanowires grown by molecular beam epitaxy (MBE) on GaAs(111)B and Si(111) substrates. In this work, we address this topic and present further understanding on the fundamental aspects. As the Mg doping was increased, structural and optical investigations revealed: i) a lower influence of the polytypic nature of the GaAs nanowires on their electronic structure; ii) a considerable reduction of the density of vertical nanowires, which is almost null for growth on Si(111); iii) the occurrence of a higher WZ phase fraction, in particular for growth on Si(111); iv) an increase of the activation energy to release the less bound carrier in the radiative state from nanowires grown on GaAs(111)B; and v) a higher influence of defects on the activation of nonradiative de-excitation channels in the case of nanowires only grown on Si(111). Back-gate field effect transistors were fabricated with individual nanowires and the p-type electrical conductivity was measured with free hole concentration ranging from 2.7 × 1016 cm−3 to 1.4 × 1017 cm−3. The estimated electrical mobility was in the range ≈0.3–39 cm2/Vs and the dominant scattering mechanism is ascribed to the WZ/ZB interfaces. Electrical and optical measurements showed a lower influence of the polytypic structure of the nanowires on their electronic structure. The involvement of Mg in one of the radiative transitions observed for growth on the Si(111) substrate is suggested.

Introduction Tobacco causes kidney damage that can progress to chronic kidney disease. However, the diagnostic parameters used in clinics are not effective in identifying smokers at risk. Our first objective is to more effectively detect subclinical renal damage in smokers. In addition, we hypothesise that tobacco consumption can predispose smokers to renal damage on exposure to other potentially nephrotoxic events (drugs, diagnostic procedures and so on). We will test this hypothesis in our second objective by investigating whether certain predisposition markers (GM2 ganglioside activator protein (GM2AP), transferrin and t-gelsolin) are able to detect smokers who are predisposed to kidney damage. Finally, in our third objective, we will study whether smoking cessation reduces subclinical and/or predisposition to renal damage.Methods and analysis For our first objective, a prospective cross-sectional study will be carried out with patients from a primary healthcare centre. The influence of tobacco on renal damage, in patients both with and without additional risk factors, will be studied using a panel of early biomarkers (albuminuria, N-acetyl-beta-D-glucosaminidase, kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin). For our second objective, a prospective longitudinal study will be carried out with patients recruited for our first objective. We will study whether certain predisposition biomarkers (GM2AP, transferrin and t-gelsolin) are able to detect smokers predisposed to renal damage. For our third objective, a prospective longitudinal study will be carried out with patients from a smoking cessation unit. We will study the evolution of the markers described above following smoking cessation.Ethics and dissemination The study has been approved by the Clinical Research Ethics Committee of the Healthcare Area of Salamanca. All study participants will sign an informed consent form in compliance with the Declaration of Helsinki and the WHO standards for observational studies. Results will be presented at conferences and submitted to peer-reviewed journals.Trial registration number NCT03850756.

ABSTRACT Here we exploit the natural properties of a synthetic nanoparticle (NP) scaffold as a subunit vaccine against enterohemorrhagic Escherichia coli (EHEC). Two EHEC-specific immunogenic antigens, namely, LomW and EscC, either alone or in combination, were covalently linked on the surface of gold nanoparticles (AuNPs) and used to immunize mice prior to challenge with EHEC O157:H7 strain 86-24. LomW is a putative outer membrane protein encoded in bacteriophage BP-933W, while EscC is a structural type III secretion system protein which forms a ring in the outer membrane. The resulting AuNP preparations, AuNP-LomW and AuNP-EscC, showed that the nanoparticles were able to incorporate the antigens, forming stable formulations that retained robust immunogenicity in vivo after subcutaneous immunization. When administered subcutaneously, AuNP-LomW or AuNP-EscC or a combination containing equivalent amounts of both candidates resulted in higher IgG titers in serum and secretory IgA titers in feces. The serum IgG titers correlated with a significant reduction in EHEC intestinal colonization after 3 days postinoculation. In addition, we showed that serum from antigen-coated AuNP-immunized mice resulted in a reduction of adherence to human intestinal epithelial cells for EHEC, as well as for two other E. coli pathotypes (enteropathogenic E. coli [EPEC], encoding EscC, and enteroaggregative E. coli [EAEC], encoding LomW). Further, the serum had antigen-specific bactericidal properties, engaging the classical complement pathway. Overall, our results demonstrate the immunogenicity and stability of a novel nanovaccine against EHEC. These results also strengthen the prospect of development of a synthetic nanoparticle vaccine conjugated to E. coli antigens as a promising platform against other enteric pathogens. IMPORTANCE Enterohemorrhagic E. coli O157:H7 is a human pathogen and the causative agent of diarrhea and hemorrhagic colitis, which can progress to hemolytic uremic syndrome. These complications represent a serious global public health problem that requires laborious public health interventions and safety control measures to combat recurrent outbreaks worldwide. Today, there are no effective interventions for the control of EHEC infections, and, in fact, the use of antibiotics is counterindicated for EHEC disease. Therefore, a viable alternative for the prevention of human infections is the development of vaccines; however, no such vaccines are approved for human use. In this study, we developed a novel gold nanoparticle platform which acts as a scaffold for the delivery of various antigens, representing a nanovaccine technology which can be applied to several disease models.

BackgroundGlanders caused by Burkholderia mallei is a re-emerging zoonotic disease affecting solipeds and humans. Furthermore, B. mallei is genetically related to B. pseudomallei, which is the causative agent of melioidosis. Both facultative intracellular bacteria are classified as tier 1 select biothreat agents. Our previous study with a B. mallei ΔtonB Δhcp1 (CLH001) live-attenuated vaccine demonstrated that it is attenuated, safe and protective against B. mallei wild-type strains in the susceptible BALB/c mouse model.Methodology/principal findingIn our current work, we evaluated the protective efficacy of CLH001 against glanders and melioidosis in the more disease-resistant C57BL/6 mouse strain. The humoral as well as cellular immune responses were also examined. We found that CLH001-immunized mice showed 100% survival against intranasal and aerosol challenge with B. mallei ATCC 23344. Moreover, this vaccine also afforded significant cross-protection against B. pseudomallei K96243, with low level bacterial burden detected in organs. Immunization with a prime and boost regimen of CLH001 induced significantly greater levels of total and subclasses of IgG, and generated antigen-specific splenocyte production of IFN-γ and IL-17A. Interestingly, protection induced by CLH001 is primarily dependent on humoral immunity, while CD4+ and CD8+ T cells played a less critical protective role.Conclusions/significanceOur data indicate that CLH001 serves as an effective live attenuated vaccine to prevent glanders and melioidosis. The quantity and quality of antibody responses as well as improving cell-mediated immune responses following vaccination need to be further investigated prior to advancement to preclinical studies.

The clinical utility of the chemotherapeutic drug cisplatin is significantly limited by its nephrotoxicity, which is characterized by electrolytic disorders, glomerular filtration rate decline, and azotemia. These alterations are consequences of a primary tubulopathy causing injury to proximal and distal epithelial cells, and thus tubular dysfunction. Oxidative stress plays a role in cisplatin nephrotoxicity and cytotoxicity, but its relative contribution to overall toxicity remains unknown. We studied the relation between the degree of oxidative reduction (provided by antioxidant treatment) and the extent of nephrotoxicity amelioration (i.e., nephroprotection) by means of a regression analysis of studies in animal models. Our results indicate that a linear relation exists between these two parameters, and that this relation very nearly crosses the value of maximal nephroprotection at maximal antioxidant effect, suggesting that oxidative stress seems to be a pivotal and mandatory mechanism of cisplatin nephrotoxicity, and, hence, an interesting, rationale-based target for clinical use. Our model also serves to identify antioxidants with enhanced effectiveness by comparing their actual nephroprotective power with that predicted by their antioxidant effect. Among those, this study identified nanoceria, erythropoietin, and maltol as highly effective candidates affording more nephroprotection than expected from their antioxidant effect for prospective clinical development.

This paper presents a hybridization of Strategic Oscillation with Path Relinking to provide a set of high-quality nondominated solutions for the Multiobjective k-Balanced Center Location problem. The considered location problem seeks to locate k out of m facilities in order to serve n demand points, minimizing the maximum distance between any demand point and its closest facility while balancing the workload among the facilities. An extensive computational experimentation is carried out to compare the performance of our proposal, including the best method found in the state-of-the-art as well as traditional multiobjective evolutionary algorithms.

Cinema is one of the most influential media of communication accessible to population, thus constituting a valuable resource for the dissemination of any kind of message. However, sometimes it can also lead to misinterpretations and a loss of veracity contemptible at all. In this paper, the plot of The Name of the Rose is analyzed from a scientific perspective, taking into account all the toxicological aspects of the poisonings that occur and framing them in their historical context, in order to clarify if the authors have remained true to reality or have opted for a more attractive fiction.

By combining 7077 SNPs and 61 microsatellites, we present the first linkage map for some of the early diverged lineages of the common frog, Rana temporaria, and the densest linkage map to date for this species. We found high homology with the published linkage maps of the Eastern and Western lineages but with differences in the order of some markers. Homology was also strong with the genome of the Tibetan frog Nanorana parkeri and we found high synteny with the clawed frog Xenopus tropicalis. We confirmed marked heterochiasmy between sexes and detected nonrecombining regions in several groups of the male linkage map. Contrary to the expectations set by the male heterogamety of the common frog, we did not find male heterozygosity excess in the chromosome previously shown to be linked to sex determination. Finally, we found blocks of loci showing strong transmission ratio distortion. These distorted genomic regions might be related to genetic incompatibilities between the parental populations, and are promising candidates for further investigation into the genetic basis of speciation and adaptation in the common frog.

This review provides a snapshot of chronic bacterial infections through the lens of Burkholderia pseudomallei and detailing its ability to establish multi-nucleated giant cells (MNGC) within the host, potentially leading to the formation of pyogranulomatous lesions. We explore the role of MNGC in melioidosis disease progression and pathology by comparing the similarities and differences of melioidosis to tuberculosis, outline the concerted events in pathogenesis that lead to MNGC formation, discuss the factors that influence MNGC formation, and consider how they fit into clinical findings reported in chronic cases. Finally, we speculate about future models and techniques that can be used to delineate the mechanisms of MNGC formation and function.