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Infectious and Parasitic Diseases (IPD) remain a challenge for medicine due to several interconnected reasons, such as antimicrobial resistance (AMR). American tegumentary leishmaniasis (ATL) is an overlooked IPD causing persistent skin ulcers that are challenging to heal, resulting in disfiguring scars. Moreover, it has the potential to extend from the skin to the mucous membranes of the nose, mouth, and throat in both humans and various animals. Given the limited effectiveness and AMR of current drugs, the exploration of new substances has emerged as a promising alternative for ATL treatment. Arrabidaea brachypoda (DC). Bureau is a native Brazilian plant rich in dimeric flavonoids, including Brachydin (BRA), which displays antimicrobial activity, but still little has been explored regarding the development of therapeutic formulations. In this work, we present the design of a low-cost liquid formulation based on the use of Pluronic F127 for encapsulation of high BRA concentration (LF-B500). The characterization techniques revealed that BRA-loaded F127 micelles are well-stabilized in an unusual worm-like form. The in vitro cytotoxicity assay demonstrated that LF-B500 was non-toxic to macrophages but efficient in the inactivation of forms of Leishmania amazonensis promastigotes with IC50 of 16.06 µg/mL. The results demonstrated that LF-B500 opened a new perspective on the use of liquid formulation-based natural products for ATL treatment.

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Reports on UCF in animals are still lacking in veterinary literature. Detailed clinical signs, laboratory findings, and follow-up information from the first cases of UCF in two ewes and two cows are provided. The cases occurred over a 12-year period. All ruminants presented a fistulous tract or perforated wound on the right ventral abdomen, emitting a foul-smelling secretion possibly associated with macerated fetal parts or placental remains. Laboratory findings included anemia, leukocytosis by neutrophilia, and hyperfibrinogenemia in one ewe, and hyperfibrinogenemia in one cow. Ovariohysterectomy and fistulectomy were performed in one ewe, while the other three ruminants were submitted for the removal of fetal parts and placental remains through the UCF. Two ewes died within 12-48 h, and the two Nelore cows had an uneventful recovery, achieving secondary intention healing within 30 to 35 days. As a never-reported or unnoticed disease of the reproductive tract, UCF is an unusual consequence of dead fetus retention in an end-stage pregnancy and a potentially life-threatening condition in ruminants, especially ewes. Further broad studies in large herds of cattle and small ruminant flocks must be conducted to estimate the incidence of UCF and ensure improvements in the diagnosis and knowledge of pathogenesis, aiming at prevention.

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Pluronic/lipid mix promises stealth liposomes with long circulation time and long-term stability for pharmaceutical applications. However, the influence of Pluronics on several aspects of lipid membranes has not been fully elucidated. Herein it was described the effect of Pluronics on the structured water, alkyl chain conformation, and kinetic stability of dimyristoylphosphatidylcholine (DMPC) liposomes using interfacial and deeper fluorescent probes along with computational molecular modeling data. Interfacial water changed as a function of Pluronics' hydrophobicity with polypropylene oxide (PPO) anchoring the copolymers in the lipid bilayer. Pluronics with more than 30-40 PO units had facilitated penetration at the bilayer while shorter PPO favored a more interfacial interaction. Low Pluronic concentrations provided long-term stability of vesicles by steric effects of polyethylene oxide (PEO), but high amounts destabilized the vesicles as a sum of water-bridge cleavage at the polar head group and the reduced alkyl-alkyl interactions among the lipids. The high kinetic stability of Pluronic/DMPC vesicles is a proof-of-concept of its advantages and applicability in nanotechnology over conventional liposome-based pharmaceutical products for future biomedical applications.

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Comparisons between the nutritional quality of organic and conventional fresh foods are frequently reported in the literature; however, discussion about processed foods is less frequent. Therefore, this study compared the nutritional content of processed products from both production systems using a systematic review of the literature and meta-analysis, regarding aspects of raw material management and processing. The study reviewed scientific articles published between 2010 and 2020 and the data obtained were analyzed using the standardized mean difference method with Hedges' adjustment and a random analytical model. Thirty-seven articles were selected, and the foods analyzed in the studies were grouped into five categories: meat products, dairy products, caught fish, wines, and fruit juices/pulps. In products of animal origin, the comparative focus shown was mainly that of the fatty acid profile, while in those of vegetable origin it was that of phytochemicals. Related to the comparison of nutrient contents, it was possible to verify the similarities in organic and conventional products in most studies; however, specific differences were verified (P < 0.05): organics contained more proteins (meat), omega 3 (dairy), and less linoleic acid (dairy and caught fish). Also, there were differences in the management of organic and conventional raw materials, and similarities in processing. Therefore, the choice for organic processed foods should not be made exclusively based on nutritional aspects, considering that the differences in nutrient contents in relation to those of conventional products are practically nonexistent.

Frequentemente são encontradas na literatura comparações entre a qualidade nutricional dos alimentos orgânicos e convencionais in natura, no entanto, pouco se discute acerca dos processados. Assim sendo, o objetivo desse estudo foi comparar o teor nutricional dos processados de ambos os sistemas de produção utilizando uma revisão sistemática da literatura e meta-análise, associando a aspectos de manejo das matérias-primas e processamento. Para isso, buscou-se artigos científicos publicados entre 2010 e 2020 e os dados obtidos foram analisados utilizando o método da diferença média padronizada com ajuste de Hedges e modelo analítico aleatório. Trinta e sete artigos foram selecionados, e os alimentos analisados em tais estudos foram agrupados em cinco categorias: cárneos, lácteos, pescado, vinhos e sucos/polpas de frutas. Nos produtos de origem animal o foco comparativo evidenciado foi principalmente o do perfil de ácidos graxos, enquanto nos de origem vegetal foi o dos fitoquímicos. Em relação à comparação do teor de nutrientes, foi possível constatar a similaridade nos orgânicos e nos convencionais na maioria dos estudos, entretanto, diferenças pontuais foram verificadas (P < 0,05): orgânicos com mais proteínas (cárneos), ômega 3 (lácteos) e menos ácido linoleico (lácteos e pescado). Também, notaram-se diferenças no manejo das matérias-primas orgânicas e convencionais, e similaridade no processamento. Portanto, a escolha por alimentos processados orgânicos não deve ser feita exclusivamente baseada em aspectos nutricionais, tendo em vista que as diferenças nos teores dos nutrientes em relação aos convencionais são praticamente inexistentes.

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Erythrosine is a dye approved for medical use that has shown promising photodynamic activity, allowing for the inactivation of microorganisms and activity against malignant cells. Despite the great photodynamic potential, erythrosine exhibits hydrophilicity, negatively impacting its action in biological membranes. Therefore, the incorporation of erythrosine in micellar polymeric systems, such as poloxamers, may overcome this limitation. Moreover, using bioadhesive and thermoresponsive polymers to combine in situ gelation and bioadhesion may enhance retention of this topically applied drug. In this work, mucoadhesive and thermoresponsive micellar systems were prepared containing erythrosine in two states: the native form (ERI) and the disodium salt (ERIs). The systems were evaluated based on the effect of ERI/ERIs on the micellar structure of the binary polymer mixtures. Optimised combinations of poloxamer 407 (polox407) and mucoadhesive sodium carboxymethylcellulose (NaCMC) or hydroxypropyl methylcellulose (HPMC) were used as micellar systems for ERI or ERIs delivery. The systems were studied with respect to theoretical interactions, qualitative composition, morphology, and micellar properties. In silico modelling indicated a higher interaction of the drug with poly(ethylene oxide) (PEO) than poly(propylene oxide) (PPO) fragments of polox407. Systems containing NaCMC displayed a repulsive effect in the presence of erythrosine, due to the polymer's charge density. Both systems could convert the photosensitizer in its monomeric form, ensuring photodynamic activity. In these mixtures, crystallinity, critical micellar temperature and enthalpy of polox407 micellisation were reduced, and micellar size, evaluated by transmission electron microscopy (TEM), showed low impact of ERI/ERIs in HPMC preparations. Aiming toward photodynamic applications, the findings showed how ERI or ERIs can affect the micellar formation of gels composed of 17.5% (w/w) polox407 and 3% (w/w) HPMC or 1% (w/w) NaCMC, important for understating their behaviour and future utilisation as erythrosine delivery systems.

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Systems composed of bioadhesive and thermoresponsive polymers can combine in situ gelation with bio/mucoadhesion, enhancing retention of topically applied drugs. The effect of bioadhesive sodium carboxymethylcellulose (NaCMC) and hydroxypropyl methylcellulose cellulose (HPMC) on the properties of thermoresponsive Pluronic® F127 (F127) was explored, including micellization and the mucoadhesion. A computational analysis between these polymers and their molecular interactions were also studied, rationalising the design of improved binary polymeric systems for pharmaceutical and biomedical applications. The morphological characterization of polymeric systems was conducted by SEM. DSC analysis was used to investigate the crystallization and micellization enthalpy of F127 and the mixed systems. Micelle size measurements and TEM micrographs allowed for investigation into the interference of cellulose derivatives on F127 micellization. Both cellulose derivatives reduced the critical micellar concentration and enthalpy of micellization of F127, altering hydrodynamic diameters of the aggregates. Mucoadhesion performance was useful to select the best systems for mucosal application. The systems composed of 17.5% (w/w) F127 and 3% (w/w) HPMC or 1% (w/w) NaCMC are promising as topical drug delivery systems, mainly on mucosal surfaces. They were biocompatible when tested against Artemia salina, and also able to release a model of hydrophilic drug in a controlled manner.

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Microbial contamination control is a public health concern and challenge for the food industry. Antimicrobial technologies employing natural agents may be useful in the food industry for these purposes. This work aimed to investigate the effect of photodynamic inactivation using curcumin in Pluronic® P123 nanoparticles (Cur/P123) at different pH and blue LED light against Staphylococcus aureus. Bacterial photoinactivation was conducted using different photosensitizer concentrations and exposure times at pH 5.0, 7.2 and 9.0. A mixture design was applied to evaluate the effects of exposure time (dark and light incubation) on the photoinhibitory effect. S. aureus was completely inactivated at pH 5.0 by combining low concentrations of Cur/P123 (7.80-30.25 µmol/L) and light doses (6.50-37.74 J/cm2). According to the mathematical model, dark incubation had low significance in bacterial inactivation at pH 5.0 and 9.0. No effect in bacterial inactivation was observed at pH 7.2. Cur/P123 with blue LED was effective in inactivating S. aureus. The antimicrobial effect of photodynamic inactivation was also pH-dependent.

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Background: Obstructive urolithiasis is a rare but potentially serious condition in equids. In the reviewed literature, there are several case reports of urolithiasis in horses and donkeys, but the only mention of this condition in mules occurred as incidental findings at a slaughterhouse. Therefore, this work aims to describe the first report and successful treatment of obstructive urethrolithiasis in a mule (Equus asinus x Equus caballus). Case: A 10-year-old castrated male mule weighing 380 kg was referred for hospital care. Tachycardia (64 beats per min), mild dehydration (7%), increased capillary filling time (3 s), slightly congested mucous membranes, and dysuria were observed. During its attempts to urinate, the mule was able to expose the penis, resulting in only dribbling of urine with reddish coloration. Urethral catheterization failed to reach the urinary bladder and revealed an obstruction at the ischial arch (7 x 4 cm), as confirmed by palpation and ultrasonography. Additionally, rectal ultrasound examination showed urine sedimentation and a single 2.36 mm vesical calculus. After sedation, local anesthesia, and surgical preparation, urethrotomy in the standing position was performed over the urethral obstruction at the ischial arch, reaching the urethrolith that fragmented during removal. Urethral catheterization from the urethrotomy site to flush the urinary bladder and urethra were performed, but the remaining vesical calculus was not retrieved. Considering the presence of a vesical calculus, severe urethral damage caused by the spiculated calculus and catheterization attempts, permanent perineal urethrostomy was performed. Laboratory tests revealed unremarkable hematological parameters, while serum biochemistry showed increased creatinine level. Urinalysis revealed cloudiness, amber appearance, countless red blood cells and bacteria, and calcium carbonate crystals. The urethrolith composition included ammonia, carbonate, and oxalate. Twelve months after surgery, the mule was healthy, the urethrostomy was viable, and no complications were recorded during this period. Discussion: Although uncommon, there are reports describing calculi of different sizes and weighing up to 803 g, causing mild to severe clinical signs according to the degree of obstruction in horses and donkeys. In the mule described here, the urethrolith did not completely obstruct the urethra, but the spiculated calculus caused dysuria and hematuria. In fact, most animals are usually referred for acute abdominal signs or hematuria and pollakiuria, but other unusual signs, such as rectal prolapse, may also be present. In the present report, the diagnosis of obstructive urethrolithiasis was established based on clinical signs and transcutaneous ultrasound of the subischial area, allowing visualization of the urethrolith. To the best of our knowledge, this is the first report of obstructive urethrolithiasis affecting a mule in Brazil. We reiterate that this condition must be included in the differential diagnosis of mules and hinnies with hematuria and dysuria, especially when associated with abdominal pain. Additionally, urethrostomy associated with urethrotomy performed on this mule in the standing position was a low-cost procedure with good results. Due to the lack of specificity regarding the food management of the mule on the previous farm, an assessment cannot be made regarding the effects of its food on urolith composition.(AU)

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Significant reductions in the water levels of lakes are influenced by droughts and freshwater demands, especially in semi-arid regions, where hydric stress is greater. The aim of this study was to investigate the dynamics of phytoplankton during two different water volume periods resulting from an extended drought in a semi-arid lake. Another objective was to compare two functional approaches to test which one of these best captures phytoplankton variability as a function of environmental variability. Multivariate analyses performed using the Reynolds Functional Groups (RFG) and Morphology-Based Functional Groups (MBFG) classification schemes indicated two periods, high and a low water volume. The results demonstrated the importance of light availability on phytoplankton assemblages as these two periods showed significant differences in water transparency and phytoplankton composition. During extended droughts the reduction in water volume enhances the development of bloom-forming cyanobacteria through the limitation of light in a eutrophic man-made lake. Moreover, both functional traits approaches demonstrated the effect of light availability on phytoplankton assemblage composition and can be applied in similar systems. However, the RFG classification provides more information and allows a more detailed description of the algal assemblages.

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This paper aimed to analyze the evolution of the quality of raw milk produced by producers in the Zona da Mata region, in the state of Minas Gerais, between 2012 and 2018. For this purpose, we used the linear mixed-effects model to analyze the monthly evolution of the results of milk composition indicators (fat, protein, and defatted dry extract - DDE), somatic cell count - SCC, and total bacterial count - TBC, from the official monthly registry of 94 milk producers, suppliers of a regions dairy. Results indicate a continuous reduction in the milk composition indicators between 2014 and 2018. For the SCC and TBC indicators, we identified only one-off reductions. The supply of a larger volume of milk was associated with increased TBC. Seasonality influenced all quality indicators analyzed. According to these results, we concluded that the analyzed quality of chilled raw milk offered by producers was proven worse from 2012 to 2018, despite the actions implemented by the National Milk Quality Improvement Program - PNMQL.(AU)

Este artigo objetivou analisar a evolução da qualidade do leite cru refrigerado produzido por produtores da região da Zona da Mata, do Estado de Minas Gerais, entre os anos de 2012 e 2018. Para tal, foi utilizado o modelo linear de efeitos mistos, a fim de analisar a evolução mensal dos resultados de indicadores de composição do leite (gordura, proteína e extrato seco desengordurado - ESD), contagem de células somáticas - CCS, e contagem bacteriana total - CBT, provenientes de análises oficiais mensais de 94 produtores de leite, fornecedores de um laticínio da região. Os resultados indicaram uma redução contínua dos indicadores de composição do leite entre os anos de 2014 e 2018. Para os indicadores de CCS e CBT foram observadas apenas reduções pontuais. O fornecimento de um maior volume de leite foi associado ao aumento da CBT. A sazonalidade influenciou todos os indicadores de qualidade analisados. De posse desses resultados, pode-se afirmar que, apesar das ações implementadas pelo Programa Nacional de Melhoria de Qualidade do Leite - PNMQL, a qualidade do leite cru refrigerado, proveniente dos produtores avaliados, piorou ao longo do período em análise.(AU)

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