Feline sporotrichosis due to Sporothrix globosa in the Metropolitan region of Buenos Aires: A case study.

We describe here the first case of feline sporotrichosis caused by Sporothrix globosa, occurring outside the epizootic area of Buenos Aires province, Argentina. Unlike cases reported with Sporothrix brasiliensis, on this occasion there was no clinical or serological evidence of zoonotic transmission through scratches or bites from the sick cat to the attending veterinarian or the person responsible for its care. This report aimed to improve the knowledge about the pathogenic profile of S. globosa.

Diagnosis of histoplasmosis: current status and perspectives.

Histoplasmosis is a worldwide-distributed systemic mycosis caused by the dimorphic fungus Histoplasma capsulatum. Its clinical manifestations range from subclinical or mild respiratory illness to progressive disseminated histoplasmosis (PDH), a life-threatening disease, whose accurate diagnosis is still challenging and limited in many countries, where this disease is highly endemic. In this regard, Histoplasma antigen testing is now included in the WHO Essential Diagnostics List. The final diagnosis of histoplasmosis is established by culture and/or visualization of the yeast cells by cytology or histopathology using specific stains. However, both procedures have limited sensitivity to detect the disease and cultures are time-consuming. Antibody detection assays are effective for the subacute and chronic clinical forms of histoplasmosis. However, their sensitivity is low in the immunocompromised host. Several molecular "in-house" tests were also developed and showed promising results, but none of these tests are commercially available and their standardization and validation are still pending. Antigen detection assays have high sensitivity in PDH cases and are of great value for the follow-up of patients with histoplasmosis; however, cross-reactivity with other related fungi are common. In addition, this assay is expensive and only performed in few laboratories. Novel protein antigen candidates have been recently identified and produced by DNA-recombinant techniques in order to obtain standardized and specific reagents for the diagnosis of histoplasmosis, as opposed to the unspecific antigens or crude extracts currently used. This review describes the currently available assays, highlighting their strengths and limitations and reports the latest approaches to achieve reliable and rapid diagnostic tests for histoplasmosis. KEY POINTS: • PDH causes thousands of deaths per year globally. • Rapid accurate diagnosis of PDH is unfeasible in many regions. • Fast, accurate, and low-cost diagnostic alternatives are currently under development.

Effect of several PEO-PPO amphiphiles on bax, bcl-2, and hTERT mRNAs: An insight into apoptosis and cell immortalization induced in hepatoma cells by these polymeric excipients.

UNLABELLED: Recent data have shown that synthetic polymers and nanomaterials display phenotypic effects in cells and signal transduction mechanisms involved in inflammation, differentiation, proliferation, and apoptosis. AIM: This article aims to investigate the effect of poly(ethylene oxide)-poly(propylene oxide) (PEO-PPO) block copolymers with a wide range of biomedical and pharmaceutical applications on apoptosis and/or cell immortalization, by flow cytometry and multiplex RT-PCR for bax, bcl-2, and human telomerase reverse transcriptase (hTERT). RESULTS: PEO-PPO amphiphiles upregulated bax and hTERT and induced apoptosis of two human hepatoma cell lines. CONCLUSIONS: PEO-PPO block copolymers-considered safe for human use-can drastically alter gene expression profiles of genes related to apoptosis/cell proliferation.

Hepatitis B virus and hepatitis D virus in blood donors from Argentina: circulation of HBsAg and reverse transcriptase mutants.

In Argentina, current procedures to ensure the safety of the blood supply for transfusion include the serologic detection of specific blood-borne infections. The aim of this study was to evaluate the prevalence and the genetic diversity of hepatitis B virus (HBV) and hepatitis D virus (HDV) in blood donor populations from two distantly located Argentine regions. Data from 56,983 blood donations from the Favaloro Foundation, in the city of Buenos Aires (Central Region), and the Central Blood Bank of Misiones Province (Northeast Region) were analyzed. Samples that were reactive for HBsAg were analyzed for HBV-DNA characterization and HDV serological and molecular analysis. The HBV prevalence was 0.12 % for HBsAg and 1.68 % for anti-HBc antibodies in Buenos Aires, and 0.73 % and 8.55 %, respectively, in Misiones. Seventy-seven HBsAg-reactive samples were analyzed by polymerase chain reaction for HBV-DNA. Subgenotypes A2, B2, C2, F1b and F4 (Buenos Aires) and F1b and D3 (Misiones) were detected. Several mutations within the major hydrophilic region of HBsAg, the reverse transcriptase, the basal core promoter, and the precore/core were detected. HDV genotype 1 was identified in Buenos Aires. This study confirms the circulation of several HBV subgenotypes, as well as known and newly identified variants, and the presence of HDV1 in this population. A thorough investigation has to be carried out to evaluate the clinical importance of some of the documented mutations as well as those detected in the HDV1 case.

Genetic diversity of Histoplasma capsulatum strains isolated from Argentina based on nucleotide sequence variations in the internal transcribed spacer regions of rDNA.

The internal transcribed spacer (ITS) regions of rDNA genes of 49 Histoplasma capsulatum (48 from clinical samples and one from soil) isolates were examined. Nucleotide sequence heterogeneity within this region was useful for phylogenetic classification of H. capsulatum and species identification. Thus, in 45 of 49 isolates we observed higher percentages of identity in the nucleotide sequences of ITS regions when the isolates studied herein were compared with those reported in our country in the South America B clade. Phylogenetic analyses of rDNA sequences corresponding to the 537 bp of the ITS region obtained from H. capsulatum isolates assigned South America type B clade (45 isolates), North America type 1 and Asia clade (2 isolates each one). H. capsulatum strains isolated from soil and from patients living in Argentina (45 of 49) clustered together with the H. capsulatum isolates of the South America B clade. The high level of genetic similarity among our isolates suggests that almost one genetic population is present in the microenvironment. Isolates described as H. capsulatum var. capsulatum or var. farciminosum (2 isolates) did not form a monophyletic group and were found in the Asia clade. Subsequent studies are needed to properly identify these isolates.

Quantitative determination of voriconazole by thionine reduction and its potential application in a pharmaceutical and clinical setting.

Voriconazole (VCZ) is a triazolic drug used to treat serious fungal infections and invasive mycosis and has also been more recently used as a generic antifungal treatment. However, VCZ therapies can cause undesirable side effects and doses must be carefully monitored before administration to avoid or reduce severe toxic effects. Analytical techniques used to quantify VCZ are mostly based on HPLC/UV and often associated with multiple technical steps as well as expensive equipment. The present work aimed to develop an accessible and affordable spectrophotometric technique in the visible range (λ = 514 nm) for the simple quantification of VCZ. The technique was based on VCZ-induced reduction of thionine (TH, red) to leucothionine (LTH, colorless) under alkaline conditions. The reaction showed a linear correlation over the range of 1.00 µg mL-1 to 60.00 µg mL-1 at room temperature, the limits of detection and quantification being 1.93 µg mL-1 and 6.45 µg mL-1, respectively. VCZ degradation products (DPs) according to 1H and 13C-NMR spectrometric determinations not only showed good agreement with the ones previously reported (DP1 and DP2 - T. M. Barbosa, G. A. Morris, M. Nilsson, R. Rittner and C. F. Tormena, RSC Adv., 2017, DOI: 10.1039/c7ra03822d), but also revealed a new degradation product (DP3). Mass spectrometry not only confirmed the presence of LTH as a result of the VCZ DP-induced TH reduction, but also revealed the formation of a novel and stable Schiff base as a reaction product between DP1 and LTH. The latter finding became significant as it stabilizes the reaction for quantification purposes, by hindering LTH ↔TH redox reversibility. This analytical method was then validated according to the ICH Q2 (R1) guidelines, and additionally, it could be demonstrated as applicable for the reliable VCZ quantification in commercially available tablets. Importantly, it also represents a useful tool for detecting toxic threshold concentrations in human plasma from VCZ-treated patients, alerting when these risky limits are exceeded. In this way, this technique independent from sophisticated equipment, highly qualifies as a low-cost, reproducible, trustable, and non-laborious alternative method for VCZ measurements from different matrices.

Scedosporium boydii finding in an immunocompromised patient and review of the literature.

BACKGROUND: Scedosporiasis is an emerging mycosis that has gained importance in recent years due to its worldwide prevalence. It is caused by species of the Scedosporium apiospermum complex. These species can cause opportunistic infections in immunocompromised patients and, occasionally, in immunocompetent patients as well. The high intrinsic antifungal resistance make these infections difficult to manage. AIMS: The objective of this study was to interpret the mycological findings in a transplant patient, together with the images obtained in the radiological studies, in order to provide an early and effective antifungal therapy. METHODS: The mycological analysis of samples taken from a heart transplant patient with radiological images suggesting a fungal infection was performed. Computed tomography scan of the head and thorax showed space-occupying lesions in both the frontal lobe and cerebellum, and multiple pulmonary nodules. The nodules were punctured and the samples obtained were analyzed according to the procedures for mycological analysis. The identity of the isolates was confirmed by nucleotide sequencing. Eventually, the antifungal susceptibility was studied. RESULTS: The fungal isolates obtained, whose identity was confirmed by sequencing, belonged to the species Scedosporium boydii. Injured tissues were surgically removed and a treatment with amphotericin B and voriconazole-minimum inhibitory concentration (MIC) 0.5µg/mL and ≥0.5µg/mL respectively - was administered. CONCLUSIONS: Although the patient died due to complications of a Klebsiella pneumoniae sepsis refractory to treatment, the progression of the fungal disease, although slow, was favourable in the early phases of the treatment due to a correct diagnosis and the antifungal susceptibility test carried out. Clinical cases of this nature highlight the need to increase the epidemiological study of these microorganisms, as well as the proper treatment of the diseases caused, in order to achieve early diagnoses that reduce the morbidity and mortality of patients.

Rapid identification of Histoplasma capsulatum directly from cultures by multiplex PCR.

The multiplex PCR developed from a suspension of the yeast fungi correctly identified fifty-one clinical of H. capsulatum var. capsulatum strains isolated from clinical samples and soil specimens. The multiplex PCR was developed by combining two pairs of primers, one of them was specific to the H. capsulatum and the other one, universal for fungi, turned out to be specific to H. capsulatum, regardless of the fungus isolate studied. Primers designed to amplify a region of about 390-bp (Hc I-Hc II) and a region of approximately 600-bp (ITS1-ITS4) were used to identify a yeast isolated as H. capsulatum when both regions could be amplified. Absolute agreement (100 % sensitivity) could be shown between this assay and the cultures of H. capsulatum according to their morphological characteristics. Failure to amplify the target DNA sequence by PCR with primers Hc I-Hc II in the presence of the ITS1-ITS4 amplicon in isolates of P. brasiliensis, Cryptococcus neoformans, Trichosporon spp, Candida glabrata, C. albicans, C. tropicalis, C. parapsilosis, C. krusei, or Penicillium marneffei was an unequivocal sign of the high specificity of this assay. The assay specificity was also found to be 100 %. Incipient yeast forms obtained from clinical samples were identified as H. capsulatum by the PCR assay described before the morphological characteristics were registered shortening the time of diagnosis.

High Salt Induces a Delayed Activation of Human Neutrophils.

High salt (NaCl) concentrations are found in a number of tissues under physiological and pathological conditions. Here, we analyzed the effects induced by high salt on the function of human neutrophils. The culture of neutrophils in medium supplemented with high salt (50 mM NaCl) for short periods (30-120 min) inhibited the ability of conventional agonists to induce the production of IL-8 and the activation of respiratory burst. By contrast, exposure to high salt for longer periods (6-18 h) resulted in the activation of neutrophils revealed by the production of high levels of IL-8, the activation of the respiratory burst, and a marked synergistic effect on the production of TNF-α induced by LPS. Increasing osmolarity of the culture medium by the addition of sorbitol or mannitol (100 mM) was shown to be completely unable to stimulate neutrophil responses, suggesting that high sodium but not an increased osmolarity mediates the activation on neutrophils responses. A similar biphasic effect was observed when the function of monocytes was analyzed. Short term exposure to high salt suppressed IL-8 and TNF-α production induced by LPS while culture for longer periods triggered the production of IL-8 but not TNF-α in the absence of LPS stimulation. Contradictory results have been published regarding how high salt modulates neutrophil function. Our results suggest that the modulation of neutrophil function by high salt is strongly dependent on the exposure time.

Identification and characterization of sirtuin enzymes in cestodes and evaluation of sirtuin inhibitors as new cestocidal molecules.

Anti-parasitic treatment of neglected tropical diseases caused by cestodes such as echinococcosis and cysticercosis relies on a small number of approved anthelmintic drugs. Furthermore, the treatment is usually prolonged and often partially effective and not well tolerated by some patients. Therefore, the identification of novel drug targets and their associated compounds is critical. In this study, we identified and characterised sirtuin enzymes in cestodes and evaluated the cestocidal potential of sirtuin inhibitors as new cestocidal molecules. Sirtuins are a highly conserved family of nicotinamide-adenine dinucleotide-lysine deacylases involved in multiple cellular functions. Here, we described the full repertoire of sirtuin-encoding genes in several cestode species. We identified six sirtuin-encoding genes that were classified into sirtuins Class I (SIRT1, SIRT2, and SIRT3), Class III (SIRT5), and Class IV (SIRT6 and SIRT7). In Echinococcus spp., sirtuin genes showed transcriptional expression throughout several developmental stages, sirtuin 2 (SIRT2) being the most expressed. To evaluate the potential of sirtuin inhibitors as new cestocidal molecules, we determined the in vitro effect of several Class I sirtuin inhibitors by motility assay. Of those, the selective SIRT2 inhibitor Mz25 showed a strong cestocidal activity in Mesocestoides vogae (syn. Mesocestoides corti) tetrathyridia at various concentrations. The Mz25 cestocidal activity was time- and dose-dependent with a half-maximal inhibitory concentration value significantly lower than that of albendazole. Additionally, Mz25 induced extensive damage in the general morphology with marked alterations in the tegument and ultrastructural features. By homology modelling, we found that cestode SIRT2s showed a high conservation of the canonical sirtuin structure as well as in the residues related to Mz25 binding. Interestingly, some non-conservative mutations were found on the selectivity pocket (an Mz25-induced structural rearrangement on the active site), which represent a promising lead for developing selective cestode SIRT2 inhibitors derived from Mz25. Nevertheless, the Mz25 molecular target in M. vogae is unknown and remains to be determined. This report provides the basis for further studies of sirtuins to understand their roles in cestode biology and to develop selective sirtuin inhibitors to treat these neglected tropical diseases.

CT findings of COVID-19-associated pulmonary aspergillosis: a systematic review and individual patient data analysis.

PURPOSE: Common CT abnormalities of pulmonary aspergillosis represent a cavity with air-meniscus sign, nodule, mass, and consolidation having an angio-invasive pattern. This study aims to conduct a systematic review and an individual patient-level image analysis of CT findings of COVID-19-associated pulmonary aspergillosis (CAPA). METHODS: A systematic literature search was conducted to identify studies reporting CT findings of CAPA as of January 7, 2021. We summarized study-level clinical and CT findings of CAPA and collected individual patient CT images by inviting corresponding authors. The CT findings were categorized into four groups: group 1, typical appearance of COVID-19; group 2, indeterminate appearance of COVID-19; group 3, atypical for COVID-19 without cavities; and group 4, atypical for COVID-19 with cavities. In group 2, cases had only minor discrepant findings including solid nodules, isolated airspace consolidation with negligible ground-glass opacities, centrilobular micronodules, bronchial abnormalities, and cavities. RESULTS: The literature search identified 89 patients from 25 studies, and we collected CT images from 35 CAPA patients (mean age 62.4 ± 14.6 years; 21 men): group 1, thirteen patients (37.1%); group 2, eight patients (22.9%); group 3, six patients (17.1%); and group 4, eight patients (22.9%). Eight of the 14 patients (57.1%) with an atypical appearance had bronchial abnormalities, whereas only one (7.1%) had an angio-invasive fungal pattern. In the study-level analysis, cavities were reported in 12 of 54 patients (22.2%). CONCLUSION: CAPA can frequently manifest as COVID-19 pneumonia without common CT abnormalities of pulmonary aspergillosis. If abnormalities exist on CT images, CAPA may frequently accompany bronchial abnormalities.

COVID-19 associated pulmonary aspergillosis in ICU patients: Report of five cases from Argentina.

Invasive pulmonary aspergillosis is a complication in critically ill patients with acute respiratory distress syndrome, especially those with severe coronavirus disease-associated pneumonia. In this study, five cases of presumed invasive pulmonary aspergillosis in one immunocompromised and four immunocompetent patients with COVID-19 in Buenos Aires are described. In all cases, the underlying conditions, clinical presentation, fungal diagnostic tests used and their results, features of the chest scan images, antifungals used and clinical outcomes are detailed.

F127 poloxamer effect on cytotoxicity induction of tumour cell cultures treated with doxorubicin.

INTRODUCTION: Hepatocellular carcinoma is the most common liver malignancy and the third leading cause of cancer death worldwide. One crucial limitation in the pharmacotherapy for this tumour is its chemotherapy-resistant nature produced by the overexpression of several members of the ATP-binding cassette protein family that efflux drugs out of cells, as observed with the breast cancer resistant protein (BCRP). OBJECTIVES: This study aimed to assess the ability of Pluronic® F127 to reverse the multidrug resistance phenotype in two human hepatocellular cell lines. METHODS: PLC/PRF/5 and SKHep1 cells were exposed to Pluronic® F127 at several concentrations. The effect of F127 on BCRP expression (mRNA and protein), mitochondrial transmembrane potential and cell hypodiploidy was assessed. Finally, the effect of this copolymer on cytotoxicity of doxorubicin in both hepatoma cell lines was investigated, as expressed by its reverse resistance index. KEY FINDINGS: It was demonstrated that F127 in both cell lines contributes to chemosensitization, as shown by BCRP down-regulation, an altered mitochondrial transmembrane potential and hypodiploidy and reverse resistance index values. A remarkable dependence of these effects significantly correlated with the copolymer concentration. CONCLUSIONS: These findings further uncover the potential usefulness of this copolymer as multidrug resistance reversal agent, increasing the efficacy of cancer therapies.

Feline sporotrichosis due to Sporothrix globosa in the Metropolitan region of Buenos Aires: A case study

Abstract We describe here the first case of feline sporotrichosis caused by Sporothrix globosa, occurring outside the epizootic area of Buenos Aires province, Argentina. Unlike cases reported with Sporothrix brasiliensis, on this occasion there was no clinical or serological evidence of zoonotic transmission through scratches or bites from the sick cat to the attending veterinarian or the person responsible for its care. This report aimed to improve the knowledge about the pathogenic profile of S. globosa.

Resumen En este trabajo se describe el primer caso de esporotricosis felina causada por Sporothrix globosa fuera del área epizoótica de Buenos Aires. A diferencia de los casos documentados de Sporothrix brasiliensis, en este no hubo evidencia clínica ni serológica de transmisión zoonótica por arañazos o mordeduras del gato enfermo a su dueño ni al veterinario que lo atendió. Con este reporte se espera contribuir a un mejor conocimiento sobre el perfil patogénico de S. globosa.

Therapy of Chronic Hepatitis C in the Era of Nanotechnology: Drug Delivery Systems and Liver Targeting.

Since the British scientist Michael Houghton along with George Kuo, Qui-Lim Choo (Chiron Corporation Emeryville), and Daniel W. Bradley (Centers for Disease Control and Prevention) codiscovered the causative agent of hepatitis C in 1989, so much progress has been made for the screening of blood donors and management of this chronic liver disease. In this regard, direct-acting antiviral agents (DAAs) have emerged as the potential "cure" of this slowly progressing and devastating disease. However, improvements are still clearly required since the anti-hepatitis C drugs currently available in the market are so extremely expensive (i.e. $94,500 for a 12-week course of treatment), that many patients will have a denied access to such drugs by their insurers. </p> <p> In the last few years, nanotechnology has emerged as a new platform for drug development, contributing significantly to the improvement of the administration and delivery of many drugs. Additionally, nanotechnologies can provide unique solutions even in poorer societies. </p> <p> This manuscript reviews the current knowledges on the available anti-hepatitis C drugs and the new drug candidates being investigated as well, and introduces the recent advances in nanocarrier-based delivery systems. Finally, the challenges in the development of drug delivery systems for the targeting of antiviral drugs to the liver are also discussed.

Prevalence of Candida albicans, Candida dubliniensis and Candida africana in pregnant women suffering from vulvovaginal candidiasis in Argentina.

BACKGROUND: Vulvovaginal candidiasis (VVC) is a vulvovaginitis commonly diagnosed in gynecology care. In recent years, the taxonomy of the most important pathogenic Candida species, such as Candida albicans have undergone significant changes. AIMS: This study examined the prevalence of C. albicans, Candida africana, and Candida dubliniensis in vaginal specimens from 210 pregnant women suffering from vulvovaginitis or having asymptomatic colonization. METHODS: Phenotypic and molecular methods were used for the identification of the species. RESULTS: During the studied period, 55 isolates of Candida or other yeasts were obtained from specimens collected from 52 patients suffering from vulvovaginitis (24.8%). C. albicans was the predominant Candida species in 42 isolates (80.7%), either alone or in combination with other species of the genus (5.7%, n=3). Additionally, nine isolates of C. albicans (50%) were obtained from asymptomatic patients (n=18). C. dubliniensis was the causative agent in 2 (3.8%) cases of VVC, and was also isolated in one asymptomatic patient. Molecular assays were carried out using specific PCR to amplify the ACT1-associated intron sequence of C. dubliniensis. The amplification of the HWP1 gene also correctly identified isolates of the species C. albicans and C. dubliniensis. No C. africana was isolated in this work. Some C. albicans isolates were either homozygous or heterozygous at the HWP1 locus. The distribution of heterozygous and homozygous C. albicans isolates at the HWP1 locus was very similar among patients suffering from VVC and asymptomatic patients (p=0.897). CONCLUSIONS: The presence of C. albicans and C. dubliniensis, and the absence of C. africana in pregnant is noteworthy.