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Burkholderia pseudomallei is an aerobic, motile, non-spore-forming gram-negative bacillus found in tropical endemic environments that causes the disease melioidosis. Melioidosis displays a diversity of clinical presentations ranging from septic shock to chronic latent infection, often with characteristic abscesses in multiple organs. Melioidosis is an opportunistic infection, with risk factors, including diabetes, alcohol use, chronic lung disease, and chronic renal disease, and these risk factors increase the severity of disease (Wiersinga et al., 2006) [1]. In this case report, we illustrate a case of a 32 year old man with several risk factors and recent travel to an endemic region presenting with melioidosis. Our case demonstrates the challenges in obtaining a diagnosis in a non-endemic location, highlights a complex presentation of this disease, and describes the multifaceted clinical management required to care for this patient. As global travel increases, there is an increased need for clinician awareness of this disease in non-endemic regions., Competing Interests: No conflicts of interest., (© 2021 The Authors.)

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), can be detected in respiratory samples by real-time reverse transcriptase polymerase chain reaction (RT-PCR) or other molecular methods. Accessibility of diagnostic testing for COVID-19 has been limited by intermittent shortages of supplies required for testing, including flocked nasopharyngeal (FLNP) swabs., Methods: We developed a 3-dimensional printed nasopharyngeal (3DP) swab as a replacement of the FLNP swab. The performance of 3DP and FLNP swabs were compared in a clinical trial of symptomatic patients at 3 clinical sites (n = 291) using 3 SARS-CoV-2 emergency use authorization tests: a modified version of the Centers for Disease Control and Prevention (CDC) RT-PCR Diagnostic Panel and 2 commercial automated formats, Roche Cobas and NeuMoDx., Results: The cycle threshold-C(t)-values from the gene targets and the RNase P gene control in the CDC assay showed no significant differences between swabs for both gene targets (P = .152 and P = .092), with the RNase P target performing significantly better in the 3DP swabs (P < .001). The C(t) values showed no significant differences between swabs for both viral gene targets in the Roche cobas assay (P = .05 and P = .05) as well as the NeuMoDx assay (P = .401 and P = .484). The overall clinical correlation of COVID-19 diagnosis between all methods was 95.88% (Kappa 0.901)., Conclusions: The 3DP swabs were equivalent to standard FLNP in 3 testing platforms for SARS-CoV-2. Given the need for widespread testing, 3DP swabs printed onsite are an alternate to FLNP that can rapidly scale in response to acute needs when supply chain disruptions affect availability of collection kits., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Preterm infants are at high risk of infection and have distinct pathogen recognition responses. Suggested mechanisms include soluble mediators that enhance cellular levels of cAMP. The aim of this study was to assess the relationship between blood cAMP concentrations and TLR-mediated cytokine production in infants during the first month of life., Methods: Cord and serial peripheral blood samples (days of life 1-28) were obtained from a cohort of very preterm (<30 weeks' gestational age) and term human infants. Whole-blood concentrations of cAMP and FSL-1 and LPS in vitro stimulated cytokine concentrations were measured by ELISA and multiplex bead assay., Results: cAMP concentrations were higher in cord than in peripheral blood, higher in cord blood of female preterm infants, and lower at Days 1 and 7 in infants exposed to chorioamnionitis, even after adjusting for leukocyte counts. TLR2 and TLR4-mediated TNF-α, IL-1β, IL-6, IL-12p70, and IL-10 production in vitro increased over the first month of life in preterm infants and were positively correlated with leukocyte-adjusted cAMP levels and reduced by exposure to chorioamnionitis., Conclusions: The ontogeny of blood cAMP concentrations and associations with chorioamnionitis and TLR-mediated production of cytokines suggest that this secondary messenger helps shape distinct neonatal pathogen responses in early life.

Background: There is a need to prevent and treat infection in newborns. One approach is administration of antimicrobial proteins and peptides (APPs) such as LL-37, a membrane-active cathelicidin antimicrobial peptide, and mannose-binding lectin (MBL), a pattern-recognition protein that binds to microbial surface polysaccharides resulting in opsonization and complement activation. Low plasma/serum levels of LL-37 and of MBL have been correlated with infection and exogenous administration of these agents may enhance host defense. Methods: The antimicrobial activity of LL-37 (15 µg/ml) or rMBL (0.5, 2 and 10 µg/ml) was tested in hirudin-anticoagulated preterm and term human cord blood (N = 12-14) against Staphylococcus aureus (SA) USA 300 (2x10 4 CFU/ml), Staphylococcus epidermis (SE) 1457 (2x10 4 CFU/ml) and Candida albicans (CA) SC5314 (1x10 4 CFU/ml). After incubation (1, 45, or 180 min), CFUs were enumerated by plating blood onto agar plates. Supernatants were collected for measurement of MBL via ELISA. Results: Preterm cord blood demonstrated impaired endogenous killing capacity against SA and SE compared to term blood. Addition of LL-37 strongly enhanced antimicrobial/antifungal activity vs SA, SE and CA in term blood and SE and CA in preterm blood. By contrast, rMBL showed modest fungistatic activity vs CA in a sub-analysis of term newborns with high basal MBL levels. Baseline MBL levels varied within preterm and term cohorts with no correlation to gestational age. In summary, exogenous LL-37 demonstrated significant antimicrobial activity against SA, SE and CA in term and SE and CA in preterm human blood tested in vitro . rMBL demonstrated modest antifungal activity in term cord blood of individuals with high baseline MBL levels. Conclusions: To the extent that our in vitro results predict the effects of APPs in vivo , development of APPs for prevention and treatment of infection should take into account host age as well as the target pathogen., Competing Interests: Competing interests: This work was funded by Shire Pharmaceuticals in the context of a sponsored research agreement.

[This corrects the article DOI: 10.1371/journal.pone.0175936.].

Background: A host defense function for Alkaline phosphatases (ALPs) is suggested by the contribution of intestinal ALP to detoxifying bacterial lipopolysaccharide (endotoxin) in animal models in vivo and the elevation of ALP activity following treatment of human cells with inflammatory stimuli in vitro. However the activity of ALP in human plasma (primarily tissue-nonspecific ALP; TNAP) on lipopolysaccharide and other microbial products has not been assessed, nor has its expression been studied in preterm newborns, a vulnerable population at high risk of sepsis. In this context, the aim of our study was to characterize the activity of TNAP on Toll-like receptor (TLR) agonists and assess the concentrations of plasma ALP during late-onset sepsis in preterm newborns., Methods: Recombinant human TNAP was incubated with microbial products and phosphate release was measured by malachite green assay. Plasma ALP activity was measured serially in a cohort of preterm (N = 129) infants at high risk of late-onset sepsis (LOS)., Results: TNAP dephosphorylates poly-inosine:cytosine (Toll-like receptor (TLR) 3 agonist) and LPS from Klebsiella pneumoniae and Salmonella minnesota (TLR4 agonists). Plasma ALP significantly increased postnatally over the first 4 weeks of life in preterm and term newborns. Bacteremic LOS in preterm infants (gestational age ≤ 30 weeks) was associated with significantly elevated plasma ALP at 4 weeks postnatal age., Conclusions: TNAP, the main circulating isozyme of ALP, de-phosphorylates TLR agonists, demonstrates a post-natal age dependent increase in preterm and term plasma across the first 4 weeks of life, and is elevated in association with preterm LOS.

Adjuvants boost vaccine responses, enhancing protective immunity against infections that are most common among the very young. Many adjuvants activate innate immunity, some via Toll-Like Receptors (TLRs), whose activities varies with age. Accordingly, characterization of age-specific adjuvant-induced immune responses may inform rational adjuvant design targeting vulnerable populations. In this study, we employed proteomics to characterize the adjuvant-induced changes of secretomes from human newborn and adult monocytes in response to Alum, the most commonly used adjuvant in licensed vaccines; Monophosphoryl Lipid A (MPLA), a TLR4-activating adjuvant component of a licensed Human Papilloma Virus vaccine; and R848 an imidazoquinoline TLR7/8 agonist that is a candidate adjuvant for early life vaccines. Monocytes were incubated in vitro for 24 h with vehicle, Alum, MPLA, or R848 and supernatants collected for proteomic analysis employing liquid chromatography-mass spectrometry (LC-MS) (data available via ProteomeXchange, ID PXD003534). 1894 non-redundant proteins were identified, of which ∼30 - 40% were common to all treatment conditions and ∼5% were treatment-specific. Adjuvant-stimulated secretome profiles, as identified by cluster analyses of over-represented proteins, varied with age and adjuvant type. Adjuvants, especially Alum, activated multiple innate immune pathways as assessed by functional enrichment analyses. Release of lactoferrin, pentraxin 3, and matrix metalloproteinase-9 was confirmed in newborn and adult whole blood and blood monocytes stimulated with adjuvants alone or adjuvanted licensed vaccines with distinct clinical reactogenicity profiles. MPLA-induced adult monocyte secretome profiles correlated in silico with transcriptome profiles induced in adults immunized with the MPLA-adjuvanted RTS,S malaria vaccine (Mosquirix™). Overall, adjuvants such as Alum, MPLA and R848 give rise to distinct and age-specific monocyte secretome profiles, paralleling responses to adjuvant-containing vaccines in vivo Age-specific in vitro modeling coupled with proteomics may provide fresh insight into the ontogeny of adjuvant action thereby informing targeted adjuvanted vaccine development for distinct age groups., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Background: Staphylococcus epidermidis causes late-onset sepsis in preterm infants. Staphylococcus epidermidis activates host responses in part via Toll-like receptor 2 (TLR2). Epidemiologic studies link bacteremia and neonatal brain injury, but direct evidence is lacking., Methods: Wild-type and TLR2-deficient (TLR2-/-) mice were injected intravenously with S. epidermidis at postnatal day 1 prior to measuring plasma and brain cytokine and chemokine levels, bacterial clearance, brain caspase-3 activation, white/gray matter volume, and innate transcriptome., Results: Staphylococcus epidermidis bacteremia spontaneously resolved over 24 hours without detectable bacteria in the cerebrospinal fluid (CSF). TLR2-/- mice demonstrated delayed S. epidermidis clearance from blood, spleen, and liver. Staphylococcus epidermidis increased the white blood cell count in the CSF, increased interleukin 6, interleukin 12p40, CCL2, and CXCL1 concentrations in plasma; increased the CCL2 concentration in the brain; and caused rapid (within 6 hours) TLR2-dependent brain activation of caspase-3 and TLR2-independent white matter injury., Conclusions: Staphylococcus epidermidis bacteremia, in the absence of bacterial entry into the CSF, impairs neonatal brain development. Staphylococcus epidermidis bacteremia induced both TLR2-dependent and -independent brain injury, with the latter occurring in the absence of TLR2, a condition associated with an increased bacterial burden. Our study indicates that the consequences of transient bacteremia in early life may be more severe than commonly appreciated, and our findings may inform novel approaches to reduce bacteremia-associated brain injury., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Extracellular adenosine, a key regulator of physiology and immune cell function that is found at elevated levels in neonatal blood, is generated by phosphohydrolysis of adenine nucleotides released from cells and catabolized by deamination to inosine. Generation of adenosine monophosphate (AMP) in blood is driven by cell-associated enzymes, whereas conversion of AMP to adenosine is largely mediated by soluble enzymes. The identities of the enzymes responsible for these activities in whole blood of neonates have been defined in this study and contrasted to adult blood. We demonstrate that soluble 5'-nucleotidase (5'-NT) and alkaline phosphatase (AP) mediate conversion of AMP to adenosine, whereas soluble adenosine deaminase (ADA) catabolizes adenosine to inosine. Newborn blood plasma demonstrates substantially higher adenosine-generating 5'-NT and AP activity and lower adenosine-metabolizing ADA activity than adult plasma. In addition to a role in soluble purine metabolism, abundant AP expressed on the surface of circulating neonatal neutrophils is the dominant AMPase on these cells. Plasma samples from infant observational cohorts reveal a relative plasma ADA deficiency at birth, followed by a gradual maturation of plasma ADA through infancy. The robust adenosine-generating capacity of neonates appears functionally relevant because supplementation with AMP inhibited whereas selective pharmacologic inhibition of 5'-NT enhanced Toll-like receptor-mediated TNF-α production in neonatal whole blood. Overall, we have characterized previously unrecognized age-dependent expression patterns of plasma purine-metabolizing enzymes that result in elevated plasma concentrations of anti-inflammatory adenosine in newborns. Targeted manipulation of purine-metabolizing enzymes may benefit this vulnerable population.

Staphylococcus epidermidis (SE) causes late onset sepsis and significant morbidity in catheterized preterm newborns. Animal models of SE infection are useful in characterizing disease mechanisms and are an important approach to developing improved diagnostics and therapeutics. Current murine models of neonatal bacterial infection employ intraperitoneal or subcutaneous routes at several days of age, and may, therefore, not accurately reflect distinct features of innate immune responses to bacteremia. In this study we developed, validated, and characterized a murine model of intravenous (IV) infection in neonatal mice <24 hours (h) old to describe the early innate immune response to SE. C57BL/6 mice <24 h old were injected IV with 10(6), 10(7), 10(8) colony-forming units (CFU) of SE 1457, a clinical isolate from a central catheter infection. A prospective injection scoring system was developed and validated, with only high quality injections analyzed. Newborn mice were euthanized between 2 and 48 h post-injection and spleen, liver, and blood collected to assess bacterial viability, gene expression, and cytokine production. High quality IV injections demonstrated inoculum-dependent infection of spleen, liver and blood. Within 2 h of injection, SE induced selective transcription of TLR2 and MyD88 in the liver, and increased systemic production of plasma IL-6 and TNF-α. Despite clearance of bacteremia and solid organ infection within 48 h, inoculum-dependent impairment in weight gain was noted. We conclude that a model of IV SE infection in neonatal mice <24 h old is feasible, demonstrating inoculum-dependent infection of solid organs and a pattern of bacteremia, rapid and selective innate immune activation, and impairment of weight gain typical of infected human neonates. This novel model can now be used to characterize immune ontogeny, evaluate infection biomarkers, and assess preventative and therapeutic modalities.

Production of IL-1beta typically requires two-separate signals. The first signal, from a pathogen-associated molecular pattern, promotes intracellular production of immature cytokine. The second signal, derived from a danger signal such as extracellular ATP, results in assembly of an inflammasome, activation of caspase-1 and secretion of mature cytokine. The inflammasome component, Nalp3, plays a non-redundant role in caspase-1 activation in response to ATP binding to P2X(7) in macrophages. Gingival epithelial cells (GECs) are an important component of the innate-immune response to periodontal bacteria. We had shown that GECs express a functional P2X(7) receptor, but the ability of GECs to secrete IL-1beta during infection remained unknown. We find that GECs express a functional Nalp3 inflammasome. Treatment of GECs with LPS or infection with the periodontal pathogen, Porphyromonas gingivalis, induced expression of the il-1beta gene and intracellular accumulation of IL-1beta protein. However, IL-1beta was not secreted unless LPS-treated or infected cells were subsequently stimulated with ATP. Conversely, caspase-1 is activated in GECs following ATP treatment but not P. gingivalis infection. Furthermore, depletion of Nalp3 by siRNA abrogated the ability of ATP to induce IL-1beta secretion in infected cells. The Nalp3 inflammasome is therefore likely to be an important mediator of the inflammatory response in gingival epithelium.

The obligate intracellular development of Chlamydia suggests that the bacteria should be vulnerable to premature host cell apoptosis, but because Chlamydia-infected cells are apoptosis resistant, this has never been able to be tested. We have devised a system to circumvent the apoptotic block imposed by chlamydial infection. When the proapoptotic protein Bim(S) was experimentally induced, epithelial cells underwent apoptosis that was not blocked by chlamydial infection. Apoptosis during the developmental cycle prevented the generation of infectious bacteria and caused transcriptional changes of bacterial genes and loss of intracellular ATP. Intriguingly, although apoptosis resulted in destruction of host cell structures and of the Chlamydia inclusion, and prevented generation of elementary bodies, Bim(S) induction in the presence of a caspase inhibitor allowed differentiation into morphologically normal but noninfectious elementary bodies. These data show that chlamydial infection renders host cells apoptosis resistant at a premitochondrial step and demonstrate the consequences of premature apoptosis for development of the bacteria.

Different Chlamydia trachomatis strains are responsible for prevalent bacterial sexually-transmitted disease and represent the leading cause of preventable blindness worldwide. Factors that predispose individuals to disease and mechanisms by which chlamydiae cause inflammation and tissue damage remain unclear. Results from recent studies indicate that prolonged survival and subsequent death of infected cells and their effect on immune effector cells during chlamydial infection may be important in determining the outcome. Survival of infected cells is favored at early times of infection through inhibition of the mitochondrial pathway of apoptosis. Death at later times displays features of both apoptosis and necrosis, but pro-apoptotic caspases are not involved. Most studies on chlamydial modulation of host-cell death until now have been performed in cell lines. The consequences for pathogenesis and the immune response will require animal models of chlamydial infection, preferably mice with targeted deletions of genes that play a role in cell survival and death.

Chlamydia are obligate intracellular bacteria that modulate apoptosis of the host cell. Strikingly, chlamydial infection has been reported both to inhibit and to induce apoptosis. Although the ability to inhibit apoptosis has been corroborated by the identification of cellular targets, confirmation of cell death induction has been complicated by a mixture of apoptotic features and atypical cell death during infection, as well as by differences in the experimental techniques used to measure cell death. Here we use a panel of well-established approaches in the study of apoptosis to define the form of cell death induced by Chlamydia trachomatis infection. Infected cells displayed apoptotic features such as nuclear condensation and fragmentation, as well as positive TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling) staining. Fragmentation of genomic DNA occurred, but was atypical. Clear evidence against the activation of effector caspases was found. Nuclear changes were measured in fibroblasts lacking one or both of the effectors of mitochondrial apoptosis, Bax and Bak. A slight reduction in nuclear changes was observed in Bax-deficient cells and in Bax/Bak double-deficient cells. Most surprisingly, this reduction was almost complete in Bak-deficient cells. Finally, dying infected cells were efficiently taken up by professional phagocytes, suggesting that Chlamydia-induced host-cell death could play a role in the immune response. In conclusion, chlamydial infection can induce cell death. Although Chlamydia-induced cell death has certain morphological features of apoptosis, it does not result from activation of the apoptotic pathway.

This present study, by applying qualitative research under a phenomenological perspective, attempts to seek an understanding of the meaning of the learning experiences of nursing students who care for child and family in the community. The data have been obtained through individual open interviews with nine students. Two themes have emerged from the analysis of the data: FACING CHALLENGES and GENERATING A NEW VIEW. Applying the theoretical approach of Viktor Frankl's existential analysis allows us to understand that what mobilizes students when facing challenges is the search for knowledge and desire to do something. Moreover, this study allows a reflection about significant learning in nursing, generating a new view as a consequence to the student feelings, thoughts and actions in the promotion of the personal and professional growth.

The present study derived from our interest in nursing practice with the undernourished children and their families. Our objectives were: to understand the social representations of the nursing team about undernourished children and their families and to analyze how these representations can interfere in the process of taking care. Based on qualitative research principles, authors adopted the social representations theoretical method. For data collection and analysis, authors used the projective techniques and speech subject analysis, respectively. Results showed an innocent conception by nursing professionals, that reproduces in the practical field a strong moral code and hygienic habits to the family and it does not propitiate the formation of a critical conscience about their citizenship rights.

The authors present a case report of nutrition recuperation in an undernourished child involved in the Integral Recuperation of Undernourished Children Project at the University Hospital in Campo Grande, Mato Grosso do Sul, Brazil. They show the importance of nursing assistance as a member of multiprofessional team in projects of this matter.

This paper reviews important aspects about teaching nursing, in order to give nursing professionals an outline of the present pedagogical approaches (Traditional, Cognitivist, Behaviorist, Humanistic, Sociocultural), so that they can reflect upon their role as educators.

Nurse managers control quality and cost of the principal service provided by long-term care agencies. Job satisfaction was higher for long-term care nurse managers in metropolitan than in rural or suburban agencies. Findings suggest that continuing education may increase task satisfaction, as well as job knowledge of diploma-prepared nurse managers.

A sample of 543 members of Midwest Alliance in Nursing and Midwest Nursing Research Society were surveyed to identify factors encouraging and discouraging research utilization. Lack of time was the factor that most discouraged research utilization. A library containing research journals was available to most service (82 percent) and educator nurses (86 percent). Computer services were more available to educators (85 percent) than service nurses (68 percent). A research newsletter was ranked as more helpful than continuing education or computer networks for keeping abreast of research findings.

The Midwest Alliance in Nursing (MAIN) used a multidirectional approach to recruit long-term care nurses to a three-year, federally funded continuing education (CE) program in geriatric nursing. Program staff used a project logo, frequent mailings, bimonthly telephone calls, a series of diverse educational offerings, and scattered social meetings to strengthen participants' identification with the project's purpose and activities. Nevertheless, several nurse dyads failed to complete the program, citing excessive workload and lack of agency support as principal reasons for withdrawal. Program staff concluded that, without strong and continuing support from their employer, even highly motivated nurses will not maintain commitment to an extended-time CE program.