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Background: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a clinical syndrome with various causes. It is not uncommon that COPD patients presenting with dyspnea have multiple causes for their symptoms including AECOPD, pneumonia, or congestive heart failure occurring concurrently. Methods: To identify clinical, radiographic, and laboratory characteristics that might help distinguish AECOPD from another dominant disease in patients with a history of COPD, we conducted a retrospective cohort study of hospitalized patients with admitting diagnosis of AECOPD who were screened for a prospective randomized controlled trial from Sep 2016 to Mar 2018. Clinical characteristics, course in hospital, and final diagnosis at discharge were reviewed and adjudicated by two authors. The final diagnosis of each patient was determined based on the synthesis of all presenting signs and symptoms, imaging, and laboratory results. We adhered to AECOPD diagnosis definitions based on the GOLD guidelines. Univariate and multivariate analyses were performed to identify any associated features of AECOPD with and without other acute processes contributing to dyspnea. Results: Three hundred fifteen hospitalized patients with admitting diagnosis of AECOPD were included. Mean age was 72.5 (SD 10.6) years. Two thirds (65.4%) had spirometry defined COPD. The most common presenting symptom was dyspnea (96.5%), followed by cough (67.9%), and increased sputum (57.5%). One hundred and eighty (57.1%) had a final diagnosis of AECOPD alone whereas 87 (27.6%) had AECOPD with other conditions and 48 (15.2%) did not have AECOPD after adjudication. Increased sputum purulence (OR 3.35, 95%CI 1.68–6.69) and elevated venous pCO2 (OR 1.04, 95%CI 1.01 – 1.07) were associated with a diagnosis of AECOPD but these were not associated with AECOPD alone without concomitant conditions. Radiographic evidence of pleural effusion (OR 0.26, 95%CI 0.12 – 0.58) was negatively associated with AECOPD with or without other conditions while radiographic evidence of pulmonary edema (OR 0.31; 95%CI 0.11 – 0.91) and lobar pneumonia (OR 0.13, 95%CI 0.07 – 0.25) suggested against the diagnosis of AECOPD alone. Conclusion: The study highlighted the complexity and difficulty of AECOPD diagnosis. A more specific clinical tool to diagnose AECOPD is needed. [ABSTRACT FROM AUTHOR]

Background: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a clinical syndrome with various causes. It is not uncommon that COPD patients presenting with dyspnea have multiple causes for their symptoms including AECOPD, pneumonia, or congestive heart failure occurring concurrently. Methods: To identify clinical, radiographic, and laboratory characteristics that might help distinguish AECOPD from another dominant disease in patients with a history of COPD, we conducted a retrospective cohort study of hospitalized patients with admitting diagnosis of AECOPD who were screened for a prospective randomized controlled trial from Sep 2016 to Mar 2018. Clinical characteristics, course in hospital, and final diagnosis at discharge were reviewed and adjudicated by two authors. The final diagnosis of each patient was determined based on the synthesis of all presenting signs and symptoms, imaging, and laboratory results. We adhered to AECOPD diagnosis definitions based on the GOLD guidelines. Univariate and multivariate analyses were performed to identify any associated features of AECOPD with and without other acute processes contributing to dyspnea. Results: Three hundred fifteen hospitalized patients with admitting diagnosis of AECOPD were included. Mean age was 72.5 (SD 10.6) years. Two thirds (65.4%) had spirometry defined COPD. The most common presenting symptom was dyspnea (96.5%), followed by cough (67.9%), and increased sputum (57.5%). One hundred and eighty (57.1%) had a final diagnosis of AECOPD alone whereas 87 (27.6%) had AECOPD with other conditions and 48 (15.2%) did not have AECOPD after adjudication. Increased sputum purulence (OR 3.35, 95%CI 1.68–6.69) and elevated venous pCO2 (OR 1.04, 95%CI 1.01 – 1.07) were associated with a diagnosis of AECOPD but these were not associated with AECOPD alone without concomitant conditions. Radiographic evidence of pleural effusion (OR 0.26, 95%CI 0.12 – 0.58) was negatively associated with AECOPD with or without other conditions while radiographic evidence of pulmonary edema (OR 0.31; 95%CI 0.11 – 0.91) and lobar pneumonia (OR 0.13, 95%CI 0.07 – 0.25) suggested against the diagnosis of AECOPD alone. Conclusion: The study highlighted the complexity and difficulty of AECOPD diagnosis. A more specific clinical tool to diagnose AECOPD is needed. [ABSTRACT FROM AUTHOR]

Testing for other I I. scapularis i coinfections should be considered if the patient has compelling clinical or laboratory findings that are consistent with a secondary pathogen or if the patient requires admission to hospital. Our patient was immunocompromised because of end-stage renal failure, and had severe human granulocytic anaplasmosis complicated by HLH and coinfection with both I B. burgdoferi i and Powassan virus. The I Ixodes scapularis i tick is a vector implicated in multiple tickborne illnesses, including Lyme disease, human granulocytic anaplasmosis, babesiosis and Powassan virus disease. [Extracted from the article]

Human immunodeficiency virus (HIV) infection remains a global epidemic. While antiretroviral therapy (ART) suppresses viral replication, cessation of ART results in viral rebound necessitating lifelong treatment. This is a result of a reservoir of latently infected cells, resistant to clearance by ART and the major obstacle in curing HIV. HIV cure strategies have focused on reactivating this latent reservoir with latency reversal agents (LRAs) along with enhancement of anti-HIV immunity to eliminate reactivated HIV. Retinoic acid (RA) derivatives are promising therapeutics that may promote clearance HIV latent reservoir allowing for definitive cure. In addition to plausible mechanisms for depleting the latent reservoir with LRA activity via the p300 acetyl transferase pathway, countering HIV-mediated suppression of RIG-I and IRF-3, and proposed induction of selective apoptosis of HIV-infected cells via RIG-I, RA may also limit HIV spread by augmenting cellular trafficking via CCR7 and CCR9 and induce accumulation of high-affinity effector CD8+ T cells that aid immune clearance of HIV-infected cells. Furthermore, due to their specificity for HIVinfected cells, retinoids are attractive agents to form the basis of multidrug regimens. Altogether, retinoids have many compelling properties as potential novel therapeutics in the cure of HIV. [ABSTRACT FROM AUTHOR]

Acanthamoeba spp. are the causative pathogens of several infections, including amoebic keratitis (AK), a vision-threatening infection. Acanthamoebae from corneal specimens of patients with AK harbor bacterial endosymbionts, which may increase virulence. We sought to understand the spectrum of bacterial endosymbionts present in clinical isolates of Acanthamoeba spp. identified in our reference parasitology laboratory. Isolates of Acanthamoeba spp. obtained from our biobank of anonymized corneal scrapings were screened for potential endosymbionts by PCR using primer pairs detecting bacteria belonging to orders Chlamydiales, Rickettsiales, or Legionellales and pan16S primers. Three primer pairs specific to the 18s rRNA gene of Acanthamoeba spp. were used for the amplification of Acanthamoeba DNA used for sequencing. Sanger sequencing of all PCR products was performed, followed by BLAST analysis for species identification. We screened 26 clinical isolates of Acanthamoeba spp. for potential endosymbionts. Five isolates (19%) were found to contain bacterial DNA belonging to Legionellales. Three (11%) contained members of the Rickettsiales and Pseudomonas genticulata was detected in a Rickettsia-positive sample. One strain (4%) contained Neochlamydia hartmannellae, a member of the Chlamydiales order. Bacterial endosymbionts are prevalent in clinical strains of Acanthamoeba causing AK isolated from corneal scrapings. The demonstration of these organisms in clinical Acanthamoeba isolates supports a potential exploration of anti-endosymbiont therapeutics as an adjuvant therapy in the treatment of AK. [ABSTRACT FROM AUTHOR]

Joseph Conrad's 'Karain: A Memory' (1897) is not often cited as a landmark of literary modernism. Conrad's Malay story appeared during the year in which The Nigger of the 'Narcissus' announced his arrival as an author with modernist ambitions. It also belongs to the same Blackwood's period of his early career that produced arguably his most celebrated work, 'Heart of Darkness'. Whereas these stories consensually exemplify Conrad's modernism, 'Karain' tends to be construed as an early working-through of the contemporary popular influences that shaped his literary output. Yet, in a significant sense, it also dramatizes the colonial encounter that defined some of the conceptual contours of modernism. This essay explores the story's composition, early transmission and reception, its self-conscious engagement with its popular cultural lineage, and Conrad's parallel emergence as a writer of 'challenging' fiction. Its aim is not merely to recuperate 'Karain' as a work of early modernism, nor simply to re-evaluate Conrad's story as a rehearsal, in terms of its interrogative relationship with imperialism, for some of his more overtly anti-colonialist fiction. Rather, its wider focus is on how Conrad's story reflects upon the nature of empire and modernism as mutually sustaining enterprises, and, counter to the view of other modernist authors such as T. S. Eliot, how colonial fiction and modernist writing are not antithetical but rather interrelated literary practices. [ABSTRACT FROM AUTHOR]

Backgound: Species of the Leishmania Viannia (L. V.) subgenus harbor the double-stranded Leishmania RNA virus 1 (LRV-1), previously identified in isolates from Brazil and Peru. Higher levels of LRV-1 in metastasizing strains of L. V. guyanensis have been documented in both human and murine models, and correlated to disease severity.Methods: Expression of proinflammatory biomarkers, including interleukin (IL) 1β, tumor necrosis factor alpha (TNF-α), CXCL10, CCL5, IL-6, and superoxide dismutase, in human macrophages infected with 3 ATCC and 5 clinical isolates of L. V. braziliensis, L. V. guyanensis, and L. V. panamensis for 24 and 48 hours were measured by commercial enzyme immunoassay. Analyses were performed at 24 and 48 hours, stratified by LRV-1 status and species.Results: LRV-1-positive L. V. braziliensis demonstrated significantly lower expression levels of TNF-α (P = .01), IL-1β (P = .0015), IL-6 (P = .001), and CXCL10 (P = .0004) compared with LRV-1-negative L. V. braziliensis. No differences were observed in strains of L. V. panamensis by LRV-1 status.Conclusions: Compared to LRV-1-negative L. V. braziliensis, LRV-1-positive strains of L. V. braziliensis produced a predominant Th2-biased immune response, correlated in humans to poorer immunologic control of infection and more severe disease, including mucosal leishmaniasis. Effects of LRV-1 on the pathogenesis of American tegumentary leishmaniasis may be species specific. [ABSTRACT FROM AUTHOR]

Background: Suboptimal agreement between molecular assays for the detection of Acanthamoeba spp. in clinical specimens has been demonstrated, and poor assay sensitivity directly imperils the vision of those affected by amoebic keratitis (AK) through delayed diagnosis. We sought to develop and validate a single Taqman real time PCR assay targeting the Acanthamoeba 18S rRNA gene that could be used to enhance sensitivity and specificity when paired with reference assays. Methods: Biobanked DNA from surplus delinked AK clinical specimens and 10 ATCC strains of Acanthamoeba was extracted. Sequence alignment of 66 18S rRNA regions from 12 species of Acanthamoeba known to cause keratitis informed design of a new TaqMan primer set. Performance of the new assay was compared to the 2 assays used currently in our laboratory. Results: Among 24 Acanthamoeba-positive and 83 negative specimens by the CDC reference standard, performance characteristics of the newly designed primer set were as follows: sensitivity 100%, specificity 94%, PPV 82.8%, and NPV 100%. Compared to culture, sensitivity of the new primer set was 100%, and specificity 96%. No cross-reactivity of the primer set to non-acanthamoebae, including Balamuthia and Naegleria, was found. Conclusions: We have validated a real time PCR assay for the diagnosis of AK, and in doing so, have overcome important barriers to rapid and sensitive detection of acanthamoebae, including limited sensitivity and specificity of commonly used assays. [ABSTRACT FROM AUTHOR]

Background: Amoebic keratitis is a potentially blinding eye infection caused by ubiquitous, free-living, environmental acanthamoebae, which are known to harbor bacterial endosymbionts. A Chlamydia-like endosymbiont has previously enhanced Acanthamoeba virulence in vitro. We investigated the potential effect of Acanthamoeba-endosymbiont coinfection in a human corneal tissue model representing clinical amoebic keratitis infection.Methods: Environmental and corneal Acanthamoeba isolates from the American Type Culture Collection were screened for endosymbionts by amplifying and sequencing bacterial 16S as well as Chlamydiales-specific DNA. Each Acanthamoeba isolate was used to infect EpiCorneal cells, a 3-dimensional human corneal tissue model. EpiCorneal cells were then treated with azithromycin, doxycycline, or control medium to determine whether antibiotics targeting common classes of bacterial endosymbionts attenuated Acanthamoeba virulence, as indicated by decreased observed cytopathic effect and inflammatory biomarker production.Results: A novel endosymbiont closely related to Mycobacterium spp. was identified in Acanthamoeba polyphaga 50495. Infection of EpiCorneal cells with Acanthamoeba castellanii 50493 and A. polyphaga 50372 led to increased production of inflammatory cytokines and cytopathic effects visible under microscopy. These increases were attenuated by azithromycin and doxycycline.Conclusions: Our findings suggest that azithromycin and doxycycline may be effective adjuvants to standard antiacanthamoebal chemotherapy by potentially abrogating virulence-enhancing properties of bacterial endosymbionts. [ABSTRACT FROM AUTHOR]

mexCD - oprJ is an envelope stress-inducible multidrug efflux operon of P seudomonas aeruginosa. A gene encoding a homologue of the NfxB repressor of this operon, PA4596, occurs downstream of oprJ and was proposed as a second repressor of this efflux operon. Inactivation of this gene had no impact on mexCD - oprJ expression in cells not exposed to envelope stress although its loss under envelope stress conditions yielded a > 10-fold increase in mexCD - oprJ expression. Consistent with PA4596 functioning as a mexCD - oprJ repressor, the purified protein was able to bind to a DNA fragment carrying the mexCD - oprJ promoter region. Expression of PA4596 was induced under conditions of envelope stress dependent on the AlgU envelope stress sigma factor, consistent with PA4596 operating under envelope stress conditions where it possibly serves to moderate envelope stress-inducible mexCD - oprJ expression. nfxB mutants showed elevated PA4596 expression and purified NfxB bound to DNA encompassing the PA4596 upstream region, an indication that NfxB functions as a repressor of PA4596 expression. Elimination of PA4596 in P . aeruginosa lacking nfxB and hyperexpressing mexCD - oprJ had no additional impact on mexCD - oprJ expression, regardless of the presence of envelope stress, suggesting that PA4596 repressor activity may be dependent on NfxB. This envelope stress-regulated repressor of mexCD - oprJ has been renamed esrC. [ABSTRACT FROM AUTHOR]

This article focuses on ‘The Planter of Malata’, the first of four tales from Joseph Conrad’s 1915 collection of short fiction, Within the Tides. Despite the weight of scholarship devoted to Conrad, this Australian-set story has yet to receive much, comparatively speaking, in the way of critical investigation. Conrad’s story is, I argue, of interest to cultural historians and literary critics alike. After briefly placing it in the context of Conrad’s personal contact with Australia during his sea years, I consider the story against a broader debate then taking place, concerning the political vision of a ‘White Australia’. I explore how Conrad’s story is attentive to an historical shift in European perceptions of Australia, from being regarded as inimical to European settlement during its early phases, to attempts during the late-nineteenth and early-twentieth century to cultivate Australia as a space solely for whites, as adumbrated in the ‘White Australia’ legislation that followed Federation in 1901. Although generally dismissed as a dry-run for Conrad’s 1915 novel Victory, and judged a critical failure by the standards set by his earlier fiction, in terms of the historical issues to which it is attuned ‘The Planter of Malata’ stands on its own as a work of considerable richness. [ABSTRACT FROM PUBLISHER]

The article explores the future of medical education at a time when it is facing the need to accommodate the growing diverse needs of its patients. Topics discussed include the changes being adopted into medical school admissions tests like the move of the Association of American Medical Colleges to integrate psychology, sociology and behavioral science into their test and the dilemma over the discordance between quality of life and length of life.