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The present work reports the isolation and biological evaluation of three dimeric xanthones from Paecilomyces sp. EJC01.1 isolated as endophytic from Schnella splendens , a typical plant of the Amazon. The compounds phomoxanthone A ( 1 ), phomoxanthone B ( 2 ) and dicerandrol B ( 3 ) were isolated by chromatographic procedures and identified by spectroscopic methods of 1D and 2D NMR and MS. The extracts and compound 1 showed antimicrobial activities against Bacillus subtilis , Escherichia coli , Staphylococcus aureus , Salmonella typhimurium and Pseudomonas aeruginosa . The compound phomoxanthone A ( 1 ) showed greater inhibitory activity against B. subtilis (MIC of 7.81 µg mL -1 ); in addition, it also pronounced inhibitory effect against promastigote forms of Leishmania amazonensis (IC 50 of 16.38 ± 1.079 µg mL -1 ) and epimastigote forms Trypanosoma cruzi (IC 50 of 28.61 ± 1.071 µg mL -1 ). To provide more information about the antibacterial activity of compound 1, an unprecedented molecular docking study was performed using S-ribosyl-homocysteine lyase (LuxS) (PDB ID 2FQO), which showed a possible interaction of phomoxanthone A with two of the residues (His58 and Cys126) that are fundamental for the catalysis mechanism in B. subtilis , which may be associated with the higher activity, when compared to other bacteria, observed in experimental studies. Additionally, quantum studies (DFT) were performed, for which a low gap value (5.982 eV) was observed, which corroborates the reactivity of phomoxanthone A. Thus, phomoxanthone A can be a good agent against pathogenic bacteria., Competing Interests: The authors declare no conflict of interest.

Leishmaniasis represents a serious world health problem, with 1 billion people being exposed to infection and a broad spectrum of clinical manifestations with a potentially fatal outcome. Based on the limitations observed in the treatment of leishmaniasis, such as high cost, significant adverse effects, and the potential for drug resistance, the aim of the present study was to evaluate the leishmanicidal activity of the compounds pseurotin A and monomethylsulochrin isolated from the biomass extract of Aspergillus sp. The chromatographic profiles of the extract were determined by high-performance liquid chromatography coupled with a diode-array UV-Vis detector (HPLC-DAD-UV), and the molecular identification of the pseurotin A and monomethylsulochrin were carried out by electrospray ionization mass spectrometry in tandem (LC-ESI-MS-MS) and nuclear magnetic resonance (NMR). Antileishmanial activity was assayed against promastigote and intracellular amastigote of Leishmania amazonensis . As a control, cytotoxicity assays were performed in non-infected BALB/c peritoneal macrophages. Ultrastructural alterations in parasites were evaluated by transmission electron microscopy. Changes in mitochondrial membrane potential were determined by flow cytometry. Only monomethylsulochrin inhibited the promastigote growth (IC 50 18.04 ± 1.11 µM), with cytotoxicity to peritoneal macrophages (CC 50 5.09 91.63 ± 1.28 µM). Activity against intracellular amastigote forms (IC 50 5.09 ± 1.06 µM) revealed an increase in antileishmanial activity when compared with promastigotes. In addition to a statistically significant reduction in the evaluated infection parameters, monomethylsulochrin altered the ultrastructure of the promastigote forms with atypical vacuoles, electron-dense corpuscles in the cytoplasm, changes at the mitochondria outer membrane and abnormal disposition around the kinetoplast. It was showed that monomethylsulochrin leads to a decrease in the mitochondrial membrane potential (25.9%, p = 0.0286). Molecular modeling studies revealed that monomethylsulochrin can act as inhibitor of sterol 14-alpha-demethylase (CYP51), a therapeutic target for human trypanosomiasis and leishmaniasis. Assessed for its drug likeness, monomethylsulochrin follows the Lipinski Rule of five and Ghose, Veber, Egan, and Muegge criteria. Furthermore, monomethylsulochrin can be used as a reference in the development of novel and therapeutically useful antileishmanial agents., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Silva-Silva, Moreira, Watanabe, de Souza, Hardoim, Taniwaki, Bertho, Teixeira, Cenci, Doring, Júnior, de Oliveira, Marinho, Calabrese, Marinho and Almeida-Souza.)

The natural compound ravenelin was isolated from the biomass extracts of Exserohilum rostratum fungus, and its antimicrobial, antiplasmodial, and trypanocidal activities were evaluated. Ravenelin was isolated by column chromatography and HPLC and identified by NMR and MS. The susceptibility of Gram-positive and Gram-negative bacteria strains to ravenelin was determined by microbroth dilution assay. Cytotoxicity was evaluated in hepatocarcinoma cells (HepG2) and BALB/c peritoneal macrophages by using MTT. SYBR Green I-based assay was used in the asexual stages of Plasmodium falciparum . Trypanocidal activity was tested against the epimastigote and intracellular amastigote forms of Trypanosoma cruzi . Ravenelin was active against Gram-positive bacteria strains, with emphasis on Bacillus subtilis (MIC value of 7.5 µM). Ravenelin's antiparasitic activities were assessed against both the epimastigote (IC 50 value of 5 ± 1 µM) and the intracellular amastigote forms of T. cruzi (IC 50 value of 9 ± 2 µM), as well as against P. falciparum (IC 50 value of 3.4 ± 0.4 µM). Ravenelin showed low cytotoxic effects on both HepG2 (CC 50 > 50 µM) and peritoneal macrophage (CC 50 = 185 ± 1 µM) cells with attractive selectivity for the parasites (SI values > 15). These findings indicate that ravenelin is a natural compound with both antibacterial and antiparasitic activities, and considerable selectivity indexes. Therefore, ravenelin is an attractive candidate for hit-to-lead development.

Historical events, such as changes in sea level during the Pleistocene glacial cycles, had a strong impact on coastal habitats, limiting connectivity and promoting the genetic divergence of various species. In this study, we evaluated the influence of climate oscillations and the possibility of estuary function as a barrier to gene flow among populations of the four-eyed fish, Anableps anableps. This species is fully estuarine-resident, has internal fertilization, is viviparous and does not migrate across long distances. These features make the four-eyed fish an excellent model for the study of evolutionary processes related to genetic differentiation of species and populations in estuaries. The evolutionary history of A. anableps was inferred from phylogeographic and population analyses using sequences of the mitochondrial DNA Control Region of 13 populations distributed in the Amazon and Northeast Coast of Brazil from Calcoene (Amapa) to Parnaiba (Piaui). The 83 retrieved haplotypes show a pattern of four distinct mitochondrial lineages, with up to 3.4% nucleotide divergence among them. The evolutionary reconstruction suggests that these lineages diverged recently in the late Pleistocene/early Holocene after the Atlantic Ocean reaching current levels. Analysis of variability, neutrality and the genetic expansion pattern revealed that the lineages have distinct characteristics, which were shaped by the different geomorphological features of coastal regions combined with sea level oscillations over a very long period of time. Only few neighboring populations show a discreet gene flow. This study may also be helpful for designing new experiments to better understand the geomorphological evolutionary history of the estuaries of the Amazon and the Northeast Coast of Brazil using estuarine-resident species as a model.

Objectives: The aim of this cross-sectional study was to evaluate whether interleukin 10 (IL10) and transforming growth factor β1 (TGFβ1) gene polymorphisms were associated with persistent IgE-mediated cow's milk allergy in 50 Brazilian children. The diagnostic criteria were anaphylaxis triggered by cow's milk or a positive double-blind, placebo-controlled food challenge. Tolerance was defined as the absence of a clinical response to a double-blind, placebo-controlled food challenge or cow's milk exposure., Method: The genomic DNA of the 50 patients and 224 healthy controls (HCs) was used to investigate five IL10 gene polymorphisms (-3575A/T, -2849A/G, -2763A/C, -1082G/A, -592C/A) and one TGFβ1 polymorphism (-509C/T)., Results: Among the five IL10 polymorphisms analyzed, homozygosis for the G allele at the -1082 position was significantly higher in the patients compared with the healthy controls (p=0.027) and in the persistent cow's milk allergy group compared with the healthy controls (p=0.001)., Conclusions: Homozygosis for the G allele at the IL10 -1082G/A polymorphism is associated with the persistent form of cow's milk allergy.

Objective: To relate obesity and asthma by comparing gender, age, initial classification of asthma, clinical control, basal forced expiratory volume in one second (FEV1) and forced expiratory flow between 25 and 75% (FEF25-75%) with rates of body mass index (BMI) in asthmatic adolescents., Methods: Cross-sectional study involving 120 asthmatics patients (1.9 male: 1 female) with a mean age of 14.1 years (9 to 20.1 years of age), classified according to asthma severity and control, and evaluated by spirometry using their basal FEV1 and FEF25-75%. The data were described by frequency, mean and standard deviation or median and range and analyzed by ANOVA, unpaired t test, Fischer's exact test, Kruskal-Wallis and Pearson's correlation, considering significant p<0.05., Results: There was no difference between gender in relation to the initial classification and the level of asthma control; 91.7% (100 cases) received initial classification as persistent and 106 cases (88.3%) were partially or totally controlled. There was no statistical difference between controlled patients and the others in relation to BMI. No significant correlations were found between zBMI and FEV1 and between zBMI and FEF25-75%, analyzing all patients and only patients with overweight or obese., Conclusions: In this study, no significant correlation was found between overweight/obesity and asthma using clinical, anthropometric and spirometric parameters.

Primary immunodeficiencies (PIDs) represent a large group of diseases that affect all age groups. Although PIDs have been recognized as rare diseases, there is epidemiological evidence suggesting that their real prevalence has been underestimated. We performed an evaluation of a series of 1,008 infants, children, adolescents and adults with well-defined PIDs from a single Brazilian center, regarding age at diagnosis, gender and PID category according to the International Union of Immunological Societies classification. Antibody deficiencies were the most common category in the whole series (61 %) for all age groups, with the exception of <2-year-old patients (only 15 %). In the >30-year-old group, antibody deficiencies comprised 84 % of the diagnoses, mostly consisting of common variable immunodeficiency, IgA deficiency and IgM deficiency. Combined immunodeficiencies represented the most frequent category in <2-years-old patients. Most congenital defects of phagocytes were identified in patients <5 -years of age, as were the diseases of immune dysregulation, with the exception of APECED. DiGeorge syndrome and ataxia-telangiectasia were the most frequent entities in the category of well-defined syndromes, which were mostly identified in patients <10-years of age. Males represented three-quarters and two-thirds of <2 -years-old and 2-5-years -old patients, respectively, whereas females predominated among the >30-year-old patients. Our data indicated that some PIDs were only detected at early ages, likely because affected patients do not survive long. In addition, our data pointed out that different strategies should be used to search for PIDs in infants and young children as compared to older patients.

The sera of a retrospective cohort (n=41) composed of children with well characterized cow's milk allergy collected from multiple visits were analyzed using a protein microarray system measuring four classes of immunoglobulins. The frequency of the visits, age and gender distribution reflected real situation faced by the clinicians at a pediatric reference center for food allergy in São Paulo, Brazil. The profiling array results have shown that total IgG and IgA share similar specificity whilst IgM and in particular IgE are distantly related. The correlation of specificity of IgE and IgA is variable amongst the patients and this relationship cannot be used to predict atopy or the onset of tolerance to milk. The array profiling technique has corroborated the clinical selection criteria for this cohort albeit it clearly suggested that 4 out of the 41 patients might have allergies other than milk origin. There was also a good correlation between the array data and ImmunoCAP results, casein in particular. By using qualitative and quantitative multivariate analysis routines it was possible to produce validated statistical models to predict with reasonable accuracy the onset of tolerance to milk proteins. If expanded to larger study groups, the array profiling in combination with the multivariate techniques show potential to improve the prognostic of milk allergic patients., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Study Design: An open-label, multicentre study was conducted to evaluate the antihypertensive efficacy of a 4-week course of losartan 50 mg plus hydrochlorothiazide 12.5 mg in Asian patients with essential hypertension whose blood pressure had previously been treated with but not controlled by valsartan 80 mg., Methods: A total of 237 eligible patients with mean trough sitting diastolic blood pressure (SiDBP) 95-115 mmHg and a mean trough sitting systolic blood pressure (SiSBP) < 190 mmHg entered the baseline period of treatment with valsartan 80 mg/day for 4 weeks. Those (n = 165) whose SiDBP remained > 90 mmHg and who were not excluded for other reasons were then switched to a single-tablet formulation of losartan 50 mg/hydrochlorothiazide 12.5 mg combination once daily for a further 4 weeks., Results: Mean SiDBP (study primary endpoint) at the end of combination therapy was reduced to 86.9 mmHg from 95.2 mmHg. SiSBP (study secondary endpoint) was reduced to 132.6 mmHg from 140.7 mmHg. Mean reductions after switching from valsartan 80 mg to losartan 50 mg/hydrochlorothiazide 12.5 mg were thus 8.3 and 8.1 mmHg for SiDBP and SiSBP, respectively (p < or = 0.001 for both outcomes). The goal of SiDBP < or = 90 mmHg was attained in 72% of the patients previously not controlled to the same level by valsartan 80 mg/day. Combination therapy with losartan 50 mg/hydrochlorothiazide 12.5 mg was generally well tolerated. Mean compliance with the losartan 50 mg/hydrochlorothiazide 12.5 mg combination was > 99%., Conclusion: These results demonstrate that in Asian patients who do not reach the goal of mean trough SiDBP < or = 90 mmHg with valsartan monotherapy at 80 mg once-daily, switching to a single-tablet combination of losartan 50 mg/hydrochlorothiazide 12.5 mg once-daily is well tolerated, provides effective control of blood pressure and is an excellent choice to achieve blood pressure reduction goals.

Cyclic tetrapeptide retrohydroxamic acids were prepared as histone deacetylase (HDAC) inhibitors and evaluated the inhibitory activity and found that they have potential as anticancer drugs.

Objective: The goal of this multicenter, double-blind, randomized, parallel-group study was to compare the effects of losartan potassium (hereafter referred to as losartan), candesartan cilexitil (hereafter referred to as candesartan), and losartan/hydrochlorothiazide (HCTZ) in patients with mild to moderate hypertension (sitting diastolic blood pressure [SiDBP] 95-115 mm Hg)., Methods: A total of 1161 patients were randomized in a 2:2:1 ratio to 12 weeks of treatment with losartan 50 mg QD, possibly titrated to 100 mg QD (n = 461); candesartan 8 mg QD, possibly titrated to 16 mg QD (n = 468); or losartan 50 mg QD, possibly titrated to losartan 50 mg plus HCTZ 12.5 mg QD (n = 232). At 6 weeks, the regimens of patients not reaching a goal SiDBP <90 mm Hg were titrated as described, whereas patients achieving this goal continued with low-dose monotherapy. The single primary end point at 12 weeks tested the equivalence of the 2 monotherapy regimens, predefined as a maximum between-treatment difference in the mean change from baseline trough SiDBP of 2.5 mm Hg., Results: At 12 weeks, changes in SiDBP/sitting systolic blood pressure (SiSBP) of -12.4/-14.4 mm Hg with losartan 50 mg/100 mg and -13.1/-15.8 mm Hg with candesartan 8 mg/16 mg demonstrated equivalence between the 2 monotherapy regimens (95% CI for difference in SiDBP, -1.6 to 0.2). At 12 weeks, the losartan 50 mg/50 mg plus HCTZ 12.5 mg regimen had reduced SiDBP/SiSBP significantly more (-14.3/-18.0 mm Hg) than either the candesartan 8 mg/16 mg (SiDBP, P = 0.045; SiSBP, P = 0.017) or losartan 50 mg/100 mg regimen (SiDBP and SiSBP, P = 0.001). During the last 6 weeks, patients whose regimen had been titrated to losartan 50 mg plus HCTZ 12.5 mg (n = 114) showed a greater reduction in SiDBP/SiSBP (-14.5/ -18.7 mm Hg) than did those whose regimen had been titrated to either losartan 100 mg (-10.5/-12.3 mm Hg; n = 211) or candesartan 16 mg (-11.5/-13.2 mm Hg; n = 206), representing a clinically meaningful > or = 2.5-mm Hg) difference. All 3 treatments were well tolerated, with few patients experiencing drug-related adverse events (6.9% losartan 50 mg/100 mg, 7.5% candesartan 8 mg/16 mg, 3.0% losartan 50 mg/ 50 mg plus HCTZ 12.5 mg). Candesartan 8 mg/16 mg increased serum uric acid levels (0.13 mg/dL; 95% CI, 0.04 to 0.23), whereas losartan 50 mg/100 mg decreased them (-0.14 mg/dL; 95% CI, -0.24 to -0.04), and losartan 50 mg/50 mg plus HCTZ 12.5 mg left them unchanged (0.06 mg/dL; 95% CI, -0.07 to 0.20)., Conclusions: Losartan 50 mg/100 mg and candesartan 8 mg/16 mg were comparable treatments in terms of blood pressure reduction. After titration, losartan 50 mg plus HCTZ 12.5 mg was superior to either candesartan 16 mg or losartan 100 mg in reducing hypertension. Losartan, but not candesartan, lowered serum uric acid levels and attenuated the expected increase in uric acid levels with HCTZ 12.5 mg.