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This review article explores the effectiveness of antibacterial drugs that inhibit protein synthesis in treating pythiosis, a difficult-to-treat infection caused by Pythium insidiosum . The article highlights the susceptibility of P. insidiosum to antibacterial drugs, such as macrolides, oxazolidinones, and tetracyclines. We examine various studies, including in vitro tests, experimental infection models, and clinical case reports. Based on our synthesis of these findings, we highlight the potential of these drugs in managing pythiosis, primarily when combined with surgical interventions. The review emphasizes the need for personalized treatment strategies and further research to establish standardized testing protocols and optimize therapeutic approaches.

We present the structural modification of a commercially available glass ionomer cement by inserting the imidazolium salt 1-n-hexadecyl-3-methylimidazolium chloride (C 16 MImCl), composing a new biomaterial with antifungal biofilm activity. Test specimens were prepared using a commercial glass ionomer cement to which 10 ppm of cetylpyridinium chloride (reference ionic antifungal agent) or C 16 MImCl were added. The feasibility and hypoallergenicity of the new biomaterial were assessed by microhardness plastic deformation and chorioallantoic membrane assays. Colony counting and scanning electron microscopy were used to evaluate the modified specimens' antibiofilm activity against three multidrug-resistant Candida species. The modified glass ionomer cement presented a strong antibiofilm activity against Candida spp., without losing its original micromechanical and hypoallergenic properties, rendering it a promising candidate for further application in dentistry., (© 2021. Sociedade Brasileira de Microbiologia.)

A 47-y-old man was bitten by a reduviid bug from the Zelus Fabricius, 1803 genus, which was hidden inside a rubber-coated boot. The bite caused immediate and sharp pain, followed by local edema and constant pruritus for 15 d. Pain and fever within the first 24 h were managed with analgesics as needed, and resolution was complete and without sequelae after 21 d., (Copyright © 2018 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.)

We evaluated the efficacy of azithromycin (50 mg/kg, every 12 h [q12h] orally) and miltefosine (25 mg/kg, q24h orally) treatments in an experimental model of vascular/disseminated pythiosis in immunosuppressed mice. Azithromycin was the only treatment able to reduce mortality. The histopathological findings showed acute vascular inflammation, pathogen dissemination, necrotizing myositis, neuritis, and arteritis. The results suggest that azithromycin, but not miltefosine, may have clinical relevance in the treatment of vascular/disseminated pythiosis., (Copyright © 2018 American Society for Microbiology.)

This study was aimed to analyze the effects of spray-dried porcine plasma (SDPP) on the health of post weaning piglets challenged with diets contaminated with aflatoxins and fumonisins. Fifty-six male piglets (7.15 ± 0.61 kg) were allocated in four groups: CTL group received a regular diet; SDPP group received a regular diet and 6% SDPP; MYC group received a diet containing 300 µg/kg aflatoxins and 8,000 µg/kg fumonisins; group MYC+SDPP received 300 µg/kg aflatoxins, 8,000 µg/kg fumonisins and 6% SDPP. The animals that received the experimental diet containing mycotoxins (MYC group) had lower weight gain at the end of the experiment compared to the other treatments. Animals receiving SDPP showed decreased urea levels throughout the experiment (P<0.05). Animals from MYC group presented an increased on reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) levels and decreased catalase activity (P<0.05). In contrast, SDPP prevented the increase of ROS and TBARS and stimulated superoxide dismutase activity (P<0.05). In conclusion, diet contaminated with mycotoxins (group MYC) caused subclinical intoxication in the piglets, as observed by the increase on free radical's production and lipid peroxidation. Conversely, SDPP presented a protective effect, minimizing the effects of oxidative stress caused by aflatoxins and fumonisins ingestion.

The in vitro susceptibility of 105 clinical and environmental strains of Aspergillus fumigatus and Aspergillus flavus to antifungal drugs, such as amphotericin B, azoles, and echinocandins was evaluated by the broth microdilution method proposed by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Following the EUCAST-proposed breakpoints, 20% and 25% of the clinical and environmental isolates of A. fumigatus, respectively, were found to be resistant to itraconazole (Minimal Inhibitory Concentration, MIC>2.0mg/L). Voriconazole showed good activity against A. fumigatus and A. flavus strains, except for one clinical strain of A. fumigatus whose MIC was 4.0mg/L. Posaconazole (≤0.25mg/L) also showed appreciable activity against both species of Aspergillus, except for six A. fumigatus strains with relatively higher MICs (0.5mg/L). The MICs for Amphotericin B ranged from 0.06 to 1.0mg/L for A. fumigatus, but were much higher (0.5-8.0mg/L) for A. flavus. Among the echinocandins, caspofungin showed a geometric mean of 0.078 and 0.113 against the clinical and environmental strains of A. flavus, respectively, but had elevated minimal effective concentrations (MECs) for seven of the A. fumigatus strains. Anidulafungin and micafungin exhibited considerable activity against both A. fumigatus and A. flavus isolates, except for one environmental isolate of A. fumigatus that showed an MEC of 1mg/L to micafungin. Our study proposes that a detailed investigation of the antifungal susceptibility of the genus Aspergillus from different regions of Brazil is necessary for establishing a response profile against the different classes of antifungal agents used in the treatment of aspergillosis., (Copyright © 2017 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.)

Context: Syzygium cumini (L.) Skeels (Myrtaceae) is a medicinal plant widely used in folk medicine for the treatment of diabetes mellitus (DM). However, studies on the use of this plant and of nanoparticle formulations against DM-related fungal infections are scarce., Objective: To evaluate the effect of the treatments with aqueous seed extract of S. cumini (ASc) and ASc-loaded polymeric nanoparticles (NPASc) on biochemical parameters in Candida albicans-infected diabetic rats., Materials and Methods: Male Wistar rats were divided into eight groups: Control, DM, C. albicans, C. albicans + ASc, C. albicans + NPASc, DM + C. albicans, DM + C. albicans + ASc and DM + C. albicans + NPASc. Rats were daily treated with ASc or NPASc (100 mg/kg) for 21 days. Biochemical parameters in serum and urine, advanced oxidation protein product (AOPP) and TBARS levels in the serum, kidney, liver and pancreas and N-acetyl-β-d-glucosaminidase (NAG) activities in kidney and urine were evaluated., Results: Biochemical and oxidative stress parameters increased in rats with DM and/or candidiasis. NPASc was more effective than ASc in decreasing glucose (56%), cholesterol (33%) and creatinine (51%) levels; serum (16%) and pancreatic (46%) AOPP and renal (48%) TBARS levels when compared with DM + C. albicans group. In C. albicans group, both treatments decreased NAG activity but did not decrease creatinine levels., Conclusions: These data suggest that the use of nanotechnology is able to improve plant extract properties such as antioxidant activity that may be useful in diabetes-related complications.

Scolicidal agents are important in the treatment of cystic echinococcosis. This study evaluated the scolicidal activity of the plant Blepharocalyx salicifolius (H.B.K.) Berg against Echinococcus ortleppi protoscoleces. The parasite species was identified by amplifying a fragment of the gene cytochrome c oxidase subunit 1 (COX 1). B. salicifolius crude extract at concentrations of 100, 200, 300 and 400 mg/mL was analyzed at different times (5, 10, 15, 30, 45 and 60 min). N-butanol and ethyl acetate fractions (100 and 200 mg/ mL) were also analyzed at 5, 10, 15 and 30 min. Both fractions showed 100% scolicidal activity at the concentration of 200 mg/mL at 5 min. Gallic acid, identified as the major compound of the ethyl acetate fraction- was responsible for the observed scolicidal activity. The results showed that crude extract and fractions of B. salicifolius have scolicidal effect against E. ortleppi protoscoleces.

Introduction:: This study evaluated the susceptibilities of oral candidiasis-derived Candida albicans, fluconazole-resistant (FR) Candida dubliniensis, and fluconazole-susceptible (FS) C. dubliniensis to synthetic antiseptics [chlorhexidine gluconate (CHX), cetylpyridinium chloride (CPC), and triclosan (TRC)] and natural compounds (carvacrol, eugenol and thymol)., Methods:: Susceptibility tests were performed based on the M27-A3 reference method. The fluconazole-resistant C. dubliniensis strains were obtained after prolonged in vitro exposure to increasing fluconazole concentrations. The geometric mean values for minimum inhibitory concentrations and minimum fungicidal concentrations were compared among the groups., Results:: Fluconazole-susceptible C. dubliniensis was more sensitive to CPC and TRC than FR C. dubliniensis and C. albicans were. However, eugenol and thymol were more active against FR C. dubliniensis. The fungicidal activities of CHX and TRC were similar for the three groups, and FR C. dubliniensis and C. albicans had similar sensitivities to CPC., Conclusions:: The resistance of C. dubliniensis to fluconazole affects its sensitivity the synthetic antiseptics and natural compounds that were tested.

The present study aimed to investigate the in vitro mutagenic activity of Origanum majorana essential oil. The most abundant compounds identified by GC-MS were γ -terpinene (25.73%), α -terpinene (17.35%), terpinen-4-ol (17.24%), and sabinene (10.8%). Mutagenicity was evaluated by the Salmonella /microsome test using the preincubation procedure on TA98, TA97a, TA100, TA102, and TA1535 Salmonella typhimurium strains, in the absence or in the presence of metabolic activation. Cytotoxicity was detected at concentrations higher than 0.04  μ L/plate in the absence of S9 mix and higher than 0.08  μ L/plate in the presence of S9 mix and no gene mutation increase was observed. For the in vitro mammalian cell micronucleus test, V79 Chinese hamster lung fibroblasts were used. Cytotoxicity was only observed at concentrations higher than or equal to 0.05  μ g/mL. Moreover, when tested in noncytotoxic concentrations, O. majorana essential oil was not able to induce chromosome mutation. The results from this study therefore suggest that O. majorana essential oil is not mutagenic at the concentrations tested in the Salmonella /microsome and micronucleus assays., Competing Interests: The authors declare that there are no competing interests regarding the publication of this paper.

Pythium insidiosum iron acquisition mechanisms are unknown. We previously showed that the iron chelator deferasirox had weak activity in vitro and in rabbits with experimental pythiosis. Here we show that deferasirox causes damage to P. insidiosum hyphae in vitro, but that activity is diminished in the presence of exogenous iron. The tissue activity of the proinflammatory enzyme adenosine deaminase and the histological pattern observed in pythiosis lesions of rabbits treated with deferasirox were similar to the ones in animals treated with immunotherapy.

We describe here the in vitro activities of azithromycin, clarithromycin, minocycline, or tigecycline alone and in combination with amphotericin B, itraconazole, terbinafine, voriconazole, anidulafungin, caspofungin, or micafungin against 30 isolates of the oomycete Pythium insidiosum. The assays were based on the CLSI M38-A2 technique and the checkerboard microdilution method. The main synergisms observed were through the combination of minocycline with amphotericin B (73.33%), itraconazole (70%), and micafungin (70%) and of clarithromycin with micafungin (73.33%)., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

Background: Pythium insidiosum is an oomycete classified in the kingdom Stramenopila. P. insidiosum hyphae are not able to initiate infection without the secretion of hydrolytic enzymes, which are considered an important factor in microbial virulence., Aims: To evaluate the extracellular enzymatic activity of 14 Brazilian P. insidiosum isolates and a standard strain (ATCC 58637) by the API-ZYM System screening method., Methods: Zoospores were grown in RPMI 1640 broth, and 65 μL of the liquid phase were inoculated in each cupule of the API-ZYM strips., Results: Differences in the enzymatic activities were observed among the isolates, although phosphohydrolases and ester hydrolases were conspicuous among all isolates. β-glucosidase was also present in most of the isolates. Enzymatic activities of α-glucosidase and chymotrypsin were not observed, differing from a previous study involving Australian isolates and intracellular enzymes., Conclusions: The discrepancy in the enzymatic profile observed among Brazilian P. insidiosum isolates reflects the phenotypic variations found in susceptibility tests., (Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

This study evaluated the in vitro activity of aminoglycoside antibiotics and tigecycline against Pythium insidiosum. The susceptibility tests were carried out using the broth microdilution method in accordance with the CLSI document M38-A2. MIC values for gentamicin, neomycin, paromomycin, and streptomycin ranged from 32 to 64 mg/liter, and the minimal fungicidal concentration (MFC) ranged from 32 to 128 mg/liter, which are incompatible with safe concentrations of these drugs in plasma in vivo. Tigecycline showed the lowest MIC (0.25 to 2 mg/liter) and MFC (1 to 8 mg/liter) range values. The in vitro susceptibility observed to tigecycline makes this drug a good option in future tests in vitro and in vivo for the management of pythiosis.

A cutaneous Pythium insidiosum reinfection was diagnosed in an equine in Brazil. Lesions with focal presentation appeared 2 years apart. The first infection and even immunotherapy were not likely to develop enough immune response to prevent reinfection. The use of adjuvants should be considered in the immunotherapy of pythiosis.

The objective of this study was to determine the effect of eight 5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-carboxyamidepyrazoles (TFDPs) on rat body temperature and baker's yeast-induced fever. TFDPs or vehicle (5% Tween 80 in 0.9% NaCl, 5 mL/kg) were injected subcutaneously and rectal temperature was measured as a function of time in 28-day-old male Wistar rats (N = 5-12 per group). Antipyretic activity was determined in feverish animals injected with baker's yeast (Saccharomyces cerevisiae suspension, 0.135 mg/kg, 10 mL/kg, ip). 3-Ethyl- and 3-propyl-TFDP (140 and 200 μmol/kg, respectively, 4 h after yeast injection) attenuated baker's yeast-induced fever by 61 and 82%, respectively. These two effective antipyretics were selected for subsequent analysis of putative mechanisms of action. We then determined the effects on cyclooxygenase-1 and -2 (COX-1 and COX-2) activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) oxidation in vitro, on tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels and on leukocyte counts in the washes of peritoneal cavities of rats injected with baker's yeast. While 3-ethyl- and 3-propyl-TFDP did not reduce baker's yeast-induced increases of IL-1β or TNF-α levels, 3-ethyl-TFDP caused a 42% reduction in peritoneal leukocyte count. 3-Ethyl- and 3-propyl-TFDP did not alter COX-1 or COX-2 activities in vitro, but presented antioxidant activity in the DPPH assay with an IC₅₀ of 39 mM (25-62) and 163 mM (136-196), respectively. The data indicate that mechanisms of action of these two novel antipyretic pyrazole derivatives do not involve the classic inhibition of the COX pathway or pyrogenic cytokine release.

Ornithocoris is a Hemiptera of the family Cimicidae that parasitizes wild and domestic birds. We considered opportune to report two isolate cases of parasitism by Ornithocoris sp. at dwellings in the municipality of Santa Maria, RS. In both cases, the residents reported the presence of insects at the night, besides intense prurid and red spots, typical of insect bites. All residents were affected, besides a dog. A great quantity of Ornithocors sp. specimens was seen on the walls, bed and leg of a child, while sleeping. Both cases occurred in the spring season when bird nests were seen near houses. It suggests that this blood sucking insect fed on humans in the absence of birds, their natural hosts.

Dipterans of the species Phaenicia sericata were captured and placed in cages in order to evaluate their biological cycle and to define the best substratum for posture and development of the larvae in controlled temperature and humidity (27 degrees C e 80% UR). Four decomposing substrata were evaluated: bovine, chicken and fish meat as well as bovine liver. No statistical differences were observed in the three first substrata and no posture occurred in the liver. The same substrata were used for feeding larvae and no interference in the larval cycle was observed. The copula occurred five days after the pupation and the posture six days after the copula. The average longevity of the adult flies was 37 days when they were fed with honey and water. According to these results the biological cycle of P. sericata in laboratory was approximately of 51 days.