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ABSTRACT The aim of this study was to compare the in vitro activity of delafloxacin with other fluoro-quinolones against bacterial pathogens recovered from inpatients with osteomyelitis, Acute Bacterial Skin and Skin-Structure Infections (ABSSSI). In total, 100 bacterial isolates (58 % Gram-negative and 42 % Gram-positive) recovered from inpatients between January and April 2021, were reidentified at species level by MALDI-TOF MS. Antimicrobial susceptibility testing was conducted using the broth microdilution method and the detection of bio-film formation was assessed through the microtiter plate assay. The screening for mecA was carried out by PCR, while mutations in the Quinolone Resistance Determining Regions (QRDR), specifically gyrA and parC, were analyzed using PCR followed by Sanger sequencing. Results showed that delafloxacin exhibited greater in vitro potency (at least 64-times) than the other tested fluoroquinolones (levofloxacin and ciprofloxacin) when evaluating Staphylococcus aureus (MIC50 ≤0.008 mg/L) and coagulase-negative Staphylococcus (MIC50 0.06 mg/L). Furthermore, delafloxacin (MIC50 0.25 mg/L) was at least 4 times more potent than other tested fluoroquinolones (MIC50 1 mg/L) against P. aeruginosa. No difference in delafloxacin activity (MIC50 0.03 mg/L) was observed against Enterobacter cloacae when compared with ciprofloxacin (MIC50 0.03 mg/L). Despite presenting low activity against K. pneumoniae isolates (22.2 %), delafloxacin exhibited twice the activity compared to both levofloxacin and ciprofloxacin. Delafloxacin also exhibited a strong activity (71.4 %–85.7 %.) against biofilm producing bacterial pathogens tested in this study. Interestingly, 82.14 % of the staphylococci tested in this study harbored mecA gene. In addition, the gyrA and parC genes in fluoroquinolone-resistant Gram-negative isolates displayed different mutations (substitutions and deletions). Herein, we showed that delafloxacin was the most active fluoroquinolone against staphylococci (including MRSA) and P. aeruginosa when compared to other fluoroquinolones such as ciprofloxacin and levofloxacin.

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ABSTRACT Dengue is a disease with a high-impact on public health worldwide. Many researches have focused on the cell receptors involved in its pathogenesis. The role of soluble isoforms of DC-SIGN (Dendritic Cell-Specific ICAM-3 Grabbing Non-integrin) receptor in the process of Dengue Virus (DENV) infection is not well understood. This work proposes to evaluate changes in the infection process of Immature Dendritic Cells (iDCs) by DENV in the presence of DC-SIGN recombinant soluble isoforms 8, 10, and 12. The recombinant isoforms were built by heterologous expression, the DENV-2 was multiplied in the Aedes albopictus C6/36 cells and quantified in BHK-21 cells, and the iDCs were produced from the THP-1 strain. Infection assays were performed in the presence of iDCs, DENV-2, and isoforms 8, 10, and 12 separately at 25, 50 and 100 ng/mL. The final viral load was estimated by qPCR and statistical analysis was performed by Kruskal-Wallis and ANOVA tests. The iDC profile was confirmed by increasing expression of CD11c, CD86, and CD209 surface markers and maintaining CD14 expression. Infection assays demonstrated a 23-fold increase in DENV viral load in the presence of isoforms 8 and 10 at 100 ng/mL compared to the viral control (p < 0.05), while isoform 12 did not alter the viral load. It was possible to conclude that at 100 ng/mL isoforms (8 and 10) can interact with DENV, increasing viral infection, and potentially acting as opsonins.

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ABSTRACT Background: Liver transplantation is the treatment for many end-stage liver diseases and hepatocellular carcinoma but shortage of available organs poses significant challenge. Many centers have used grafts from donors with positive anti-HBc serology but concerns about potential hepatitis B virus reactivation and de novo hepatitis B infection have raised questions about the safety of this approach. This study aimed to evaluate the survival of liver transplant recipients from anti-HBc-positive-donors and assess the risk of hepatitis B reactivation and de novo hepatitis B. Patients and methods: A retrospective single-center cohort study was conducted from 2002 to 2018, comparing who received grafts from anti-HBc-positive-donors to those from anti-HBc-negative-donors. The primary outcome was survival and description cases of hepatitis B reactivation/de novo hepatitis B. Results: We analyzed 1,111 liver transplants, in which 993 (89 %) received grafts from anti-HBc-negative-donors and 118 (11 %) from anti-HBc-positive-donors. Median age of recipients from anti-HBc-positive donors was 56 years and from anti-HBc-negative donors was of 53 years (p = 0.001). Male sex was predominant in both groups. Factors associated with death in multivariate analysis were retransplantation, early allograft dysfunction, high MELD, recipient over 60 years and female donor. The utilization of grafts from anti-HBc-positive-donors did not increase mortality. The majority of HBV reactivation and de novo hepatitis B occurred in anti-HBc positive recipients. The risk of hepatitis B reactivation/de novo hepatitis B was low and manageable. Conclusion: The study supports safety of liver grafts from anti-HBc-positive donors when employing antiviral prophylaxis. These findings contribute to expand donor options and improve patient outcomes

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ABSTRACT Introduction: Streptococcus pneumoniae colonization patterns are influenced by host and environmental factors, which may be related to Invasive Pneumococcal Disease (IPD). Interestingly, COVID-19 pandemic witnessed a decline in the incidence of IPDs. Investigations with diligent data collection on the prevalence of nasopharyngeal colonization and associated serotypes during this unique period can yield novel insights. The aim of the current study was to assess the prevalence of S. pneumoniae carriage among children and adults who have sought care at emergency departments with suspected COVID-19. Methods: In this cross-sectional study, adults and children presenting with signs and symptoms likely associated with COVID-19 in two outpatient clinics in Southern Brazil were invited to participate. RT-PCR with a comprehensive molecular panel for pneumococcal identification of the 21 most prevalent serotypes in Latin America was performed on all enrolled subjects. Prevalence of pneumococcal carriage was assessed in the age groups (< 2, ≥ 2-5, ≥ 5-11, ≥ 11-18, ≥ 18-60, ≥ 60). Results: A total of 1644 subjects were included in the study. Pneumococcal carriage was detected by PCR testing in 14.9% (245/1,644), and serotype identification occurred in 42.0% (103/245) of the participants, with a total frequency of 111. The most frequent serotype identified was 19A (25.2%, n = 28/111), followed by 6C/6D (17.1%, n = 19/111), and 23A (11.7%, n = 13/111), also highlighting the high frequency of non-vaccine se-rotypes found across all age groups. Discussion: 19A serotype, as well other most frequent serotypes identified are not covered by the PCV-10 in a community setting where PCV-10 is widely available. This finding reinforces the need for continuous surveillance to determine the impact of pneumococcal vaccination and guide public health decision-making. High 19A serotype prevalence is critical in the decision-making process for electing the best options for pneumococcal conjugate vaccines.

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ABSTRACT The global impact of the SARS-CoV-2 (severe acute respiratory syndrome Coronavirus 2) pandemic in 2019-2020 has led to significant changes in worldwide vaccination and immune prophylactic approaches. In this study, our research delves into a new immunization strategy that does not involve the use of additional adjuvants or preservatives, focusing on the effects of virus fusion with a bacterial nanostructure. The experimental procedures outlined in this paper involved the cultivation of SARS-CoV-2, the production, extraction, and nano-characterization of outer membrane vesicles (OMV) from Neisseria meningitidis, immunization of mice with two doses of OMV combined with SARS-CoV-2, and the use of mesoporous silica SBa15 and SBa16 adsorbed to the same virus. The immune response was assessed through an indirect elisa method, analysis of cytokine expression profiles, and seroneutralization of the SARS-CoV-2 strain. The characterizations of associated OMV - SARS-CoV-2 and adsorption SBa15 and SBa16 were performed using Nanosight Tracking Analysis (NTA), which showed a high density of particles in the formulation, mice were then immunized, resulting in an immune response that produced high levels of neutralizing antibodies in IgG and IgG1 mouse immunoglobulins. In addition, expressions of IL-2, IL-4, and IL-23 in spleen cells were reinforced after the vaccination process. The comparative study of these three vaccine formulations has shown that the development of new vaccines for SARS-CoV-2 should take into consideration the production of neutralizing antibodies and the maintenance of immunological memory.

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ABSTRACT Background: HIV/AIDS remains a highly stigmatizing disease worldwide, preventing people with risk or infection from testing to learn their HIV status, accessing supportive services, or taking antiretroviral therapy. Despite many studies of HIV in blood donors, no studies have evaluated the factors that contribute to stigma surrounding this illness following notification process and counseling provided by blood centers. Methods: A cross-sectional questionnaire-based survey was conducted between 2016 and 2017. Persons with HIV were invited to return to the blood center for an audio computer-assisted interview after participation in an HIV risk factor assessment study conducted from 2007 to 2016. The questionnaire was based on HIV risk interviews developed by the US CDC, with modifications appropriate to the Brazilian setting which aimed to evaluate their follow-up activities, perceptions of HIV stigma and discrimination, and the quality of counseling and notification after the donation that tested positive for HIV. Response frequencies and adjusted odds ratios from multivariable logistic regression analyses are reported. Results: 268 HIV-positive blood donors agreed to participate in the study. Almost all participants, 262 (97 %), rated as very important or important the blood center counseling experience in their decision to seek health care. One-hundred-five (39 %) participants reported none to low levels of stigma, and 163 (61 %) participants moderate stigma. Individuals reporting heterosexual orientation (OR=2.13, 95 % CI [1.08-4.22]) and healthcare-seeking behavior (OR=2.46, 95 % CI [1.10-5.48]) had significantly increased odds of reporting moderate levels of stigma. Conclusions: Our study provides information about perceived stigma and discrimination in the Brazilian blood donor population and reinforces the importance of the counseling process in linkage to care and reducing HIV-related stigma.

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ABSTRACT Background: Antiretroviral drug simplification is a strategy to reduce drug exposure and improve treatment adherence. Nowadays, dolutegravir plus lamivudine is the most preferred regimen, which might lead in the future with problems related to drug resistance or drug intolerance. This meta-analysis aimed to assess the safety of HAART simplification without integrase inhibitors. Methods: We conducted a systematic review and meta-analysis using the Embase and Medline databases to include clinical trials and observational studies published between 2008 and March 2024. The studies focused on HIV-positive individuals with suppressed viral load who either simplified their treatment to dual therapy without integrase inhibitors or continued triple therapy. The primary outcome of interest was the likelihood of viral failure within 48 weeks. Results: Ten studies were included, with a total of 1,977 patients. Boosted Protease Inhibitors (PI) were the core of antiretroviral simplification therapy. The simplification group did not show an increased risk of virological failure, with a pooled RR in 48 weeks of 1.29 (0.61-2.73, I2 = 51 %) when compared to control group. Boosted protease inhibitors were preferred combined with lamivudine, nevirapine, efavirenz, and maraviroc). Only maraviroc plus boosted PI combination was associated with a higher risk of virological failure with an RR of 4.49 (1.99-10.11). Conclusion: Simplification therapy with boosted PI plus lamivudine or non-nucleoside transcriptase reverse inhibitors was a safe strategy and not associated with a higher risk of virological failure. This approach might be an alternative to dolutegravir-based simplification regimens if needed.

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ABSTRACT Lyme borreliosis is a frequently encountered tick-borne infection worldwide, caused by a spirochete from the Borrelia burgdorferi genoscpecies. In most cases, the initial sign of Lyme disease is the pathognomonic symptom – erythema migrans rash appearing at the site of the thick bite. Other described cutaneous manifestations besides erythema migrans – such as erythema nodosum (an acute nodular septal panniculitis), papular urticaria, granuloma annulare, psoriatic changes, lichen striatus et atrophicans, Henoch-Schonlein purpura, and morphea – could potentially present as an initial/first sign of acute Borrelia burgdorferi infection. Serological testing for Lyme disease is only reliable after the initial stages of the disease. Additional PCR or serological examinations such as ELISA, immunoblot, indirect immunofluorescence examination could be performed. The diverse cutaneous manifestations of Lyme disease can lead to delays or ineffectiveness in treatment, as these symptoms may not be promptly identified as signs of the infection. Therefore, a comprehensive evaluation of the three key aspects – clinical findings, serology, and histology – is essential and should be considered collectively. We present a 78-year-old female with an acute form of Borrelia infection following a thick bite, manifesting as erythema nodosum on the lower extremities. Serology confirmed the presence of Borrelia infection, and the histological findings were indicative of erythema nodosum. The patient initially received anti-inflammatory and antibiotic medications. Reverse development of the nodules was observed after therapy with ceftriaxone, methylprednisolone, esomeprazole, and local dressings with povidone-iodine. For outpatient care, her regimen consisted of systemic reduction of the corticosteroid therapy, esomeprazole, and doxycycline. Due to the potential triggering of erythema nodosum by valsartan, it was recommended switching to an alternative medication. The rarity of erythema nodosum as an initial or first sign of acute Borrelia infection is being discussed.

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ABSTRACT American trypanosomiasis or Chagas disease is a vector-borne infection caused by the protozoan parasite Trypanosoma cruzi, characterized by acute and chronic phases; reactivations due to immunosuppression can occur. In this case report, we confirm the presence of trypomastigotes of T. cruzi in a patient with neurologic manifestations. For this purpose, a battery of techniques, including direct examination of cerebrospinal fluid, Giemsa stains, sample cultures, serology and molecular techniques were employed. The patient was treated with nifurtimox for 6 months and started antiretroviral therapy as the concomitant diagnosis of HIV was also performed, showing no sequelae nor adverse effects. A follow-up of the patient’s health status was performed for 42 months.

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ABSTRACT Group B Streptococcus (GBS) is a significant pathogen responsible for neonatal infections, primarily transmitted through maternal carriage. However, current preventive strategies, such as intrapartum antibiotic prophylaxis, present limitations and are ineffective in preventing late-onset neonatal infections. This study aimed to assess the prevalence and serotype distribution of GBS in the nasopharynx of women of reproductive age, providing data to the potential implementation of a novel hexavalent capsular vaccine (GBS6). Nasopharyngeal swabs were collected from 500 women and analyzed using a qPCR assay targeting the cfb gene to detect GBS and the cps locus. GBS was identified in 7.4 % of patients, with serotype Ia being the most prevalent. Other serotypes detected included II, V, Ib, III, and IV. These findings suggest that the nasopharynx may act as a reservoir for GBS in women of reproductive age. The results also highlight the importance of developing preventive strategies focused on upper respiratory tract colonization. Additionally, the potential introduction of the GBS6 vaccine could provide significant coverage against circulating GBS serotypes.