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Abstract Background: The COVID-19 pandemic has posed significant challenges to global healthcare systems, particularly impacting individuals with pre-existing conditions like hypertension. This study sought to assess the impact of the antihypertensive medications, losartan and enalapril maleate on SARS-CoV-2 infected cells. Vero E6 cells were infected and treated in vitro, evaluating cell viability via the MTT colorimetric assay. Additionally, the study measured relative levels of viral RNA and selected gene messenger RNAs using reverse transcriptase followed by quantitative real-time polymerase chain reaction. Results: The findings revealed that losartan substantially reduced nucleocapsid RNA levels of SARS-CoV-2 to nearly undetectable levels, while enalapril maleate did not demonstrate a significant effect. In response to viral infection, the expression of il-18, p53, p21, and p62 increased compared to uninfected-untreated cells. Notably, il-6 expression was upregulated by both infection and treatments. A comparison between infected cells treated with losartan or enalapril maleate highlighted the presence of distinct profiles in the expression of il-6, p53, p21, and p62. Conclusions: The data from our study suggest that these medications could interfere with certain effects triggered by SARS-CoV-2 infection in Vero E6 cells. However, their influence appears to vary both quantitatively and qualitatively in the modulation of metabolic and signal transduction pathways.

Abstract There has been a dramatic increase in the identification of non-canonical translation and a significant expansion of the protein-coding genome. Among the strategies used to identify unannotated small Open Reading Frames (smORFs) that encode microproteins, Ribosome profiling (Ribo-Seq) is the gold standard for the annotation of novel coding sequences by reporting on smORF translation. In Ribo-Seq, ribosome-protected footprints (RPFs) that map to multiple genomic sites are removed since they cannot be unambiguously assigned to a specific genomic location. Furthermore, RPFs necessarily result in short (25-34 nucleotides) reads, increasing the chance of multi-mapping alignments, such that smORFs residing in these regions cannot be identified by Ribo-Seq. Moreover, it has been challenging to identify protein evidence for Ribo-Seq. To solve this, we developed Rp3, a pipeline that integrates proteogenomics and Ribosome profiling to provide unambiguous evidence for a subset of microproteins missed by current Ribo-Seq pipelines. Here, we show that Rp3 maximizes proteomics detection and confidence of microprotein-encoding smORFs.

The crystallographic structure of the FolB enzyme from Mycobacterium tuberculosis (MtFolB), complexed with its inhibitor 8-mercaptoguanine (8-MG), was elucidated at a resolution of 1.95 Å. A novel series of S8-functionalized 8-MG derivatives were synthesised and evaluated as in vitro inhibitors of dihydroneopterin aldolase (DHNA, EC 4.1.2.25) activity of MtFolB. These compounds exhibited IC50 values in the submicromolar range. Evaluation of the activity for five compounds indicated their inhibition mode and inhibition constants. Molecular docking analyses were performed to determine the enzyme-inhibitor intermolecular interactions and ligand conformations upon complex formation. The inhibitory activities of all compounds against the M. tuberculosis H37Rv strain were evaluated. Compound 3e exhibited a minimum inhibitory concentration in the micromolar range. Finally, Compound 3e showed no apparent toxicity in both HepG2 and Vero cells. The findings presented herein will advance the quest for novel, specific inhibitors targeting MtFolB, an attractive molecular target for TB drug development.

IntroductionAntifolates were among the first broad-spectrum compounds used as antimycobacterial agents and can still be of use when no other therapeutic options are available. The discovery of compounds targeting the essential folate synthesis pathway could lead to new therapeutic agents to treat tuberculosis (TB). In particular, the enzyme required for the conversion of 7,8-dihydroneopterin (DHNP) to 6-hydroxymethyl-7,8-dihydropterin (HP) and glycolaldehyde (GA) in the folate pathway (MtbFolB, a dihydroneopterin aldolase - DHNA, EC 4.1.2.25), has received little attention as a potential drug target so far, as it is acting upstream of the clinically validated targets dihydropteroate synthase (DHPS; EC 2.5.1.15) and dihydrofolate reductase (DHFR; EC 1.5.1.3).MethodsWe conducted a small-scale diversity screening to identify MtbFolB inhibitors using a microplate-based enzyme inhibition assay. A total of 6,074 compounds were assembled, tested and confirmed in dose-response studies. A preliminary structure activity analysis was performed for the validated hit compounds, along with kinetic inhibition, time-dependent inhibition, as well as docking studies. ResultsThe screening resulted in the selection of 19 hits spanning 5 independent clusters. Dose-response studies of re-synthesized hits and newly synthesized derivatives displayed compounds with IC50 values ranging from 2.6 to 47 µM. The structure activity analysis revealed that bi-sulfonamide compounds could be explored for further optimizations. Docking studies highlighted two modes of binding for pyrazol-3-one compounds and, for the sulfonamide series, indicated several interactions with the catalytic Tyrosine-54 (Tyr54D) and Lysine-99 (Lys99A) residues of MtbFolB. DiscussionThrough this work, we established that the MtbFolB assay was able to select small molecules with inhibitory activities, opening prospects for larger scale screening. The sulfonamide compound 13 was also identified as the first compound directed against MtbFolB with an antimycobacterial activity.

Neural networks have been used in various computer vision applications, including noise removal. However, removing seismic noise via deep learning approaches faces a specific issue: the scarcity of labeled data. To address this difficulty, this work introduces an adaptation of the Noise2Self algorithm featuring a one-shot learning approach tailored for the seismic context. Essentially, the method leverages a single noisy image for training, utilizing a context-centered masking system and convolutional neural network (CNN) architectures, thus eliminating the dependence on previously labeled data. In tests with Gaussian noise, the method was competitive with established approaches such as Noise2Noise. Under real noise conditions, it demonstrated effective noise suppression removal for a smaller architecture. Therefore, our proposed method is a robust alternative for noise removal that is especially valuable in scenarios lacking sufficient data and labels. With a new approach to processing seismic images, particularly in terms of denoising, our method contributes to the ongoing evolution and enhancement of techniques in this field.

Despite the advancements in indirect monolithic restorations, technical complications may occur during function. To overcome this issues, intraoral repair using resin composite is a practical and low-cost procedure, being able to increase the restoration’s longevity. This review aimed to evaluate the need for repair and suggest a standardized repair protocol to the main indirect restorative materials. For this, studies were surveyed from PubMed with no language or date restriction, to investigate the scientific evidence of indirect monolithic restoration repair with direct resin composite. A classification to guide clinical decisions was made based on the FDI World Dental Federation criteria about defective indirect restorations considering esthetic and functional standards, along with the patient’s view, to decide when polishing, repairing or replacing a defective restoration. Based on 38 surveyed studies, different resin composite intraoral repair protocols, that included mechanical and chemical aspects, were defined depending on the substrate considering resin-based, glass-ceramic or zirconia restorations. The presented criteria and protocols were developed to guide the clinician’s decision-making process regarding defective indirect monolithic restorations, prolonging longevity and increasing clinical success.

Objective: To evaluate the effect of different surface treatments on the morphology, shear bond, and flexural fatigue strength of a repaired translucent zirconia. Methods: Monolithic disc-shaped specimens of translucent zirconia were prepared and ground to simulate repair areas. Four groups underwent different treatments: Air-MDP (air-abrasion with alumina particles and 10-MDP primer), Si-Sil (silica-coated alumina particles with MDP-containing silane), Si-MDP (silica coating with 10-MDP primer), and Uni adhe (universal adhesive). After roughness measurements and treatments, repairs were done using resin composite. Shear bond and flexural (n = 15) fatigue tests were performed. Surface topography, interfacial analysis, fractographic, and finite element analysis were conducted. Results: The zirconia roughness was similar between the groups, however, the surface topography was modified according to the surface treatments. Si-Sil generated higher and more stable bond strength values (20.69 MPa) between translucent zirconia and resin composite when compared to Uni adhe (15.75 MPa) considering the fatigue bond strength scenario, while it was similar to Si-MDP (17.70 MPa) and Air-MDP (18.97 MPa). Regarding the mechanical behavior, Si-Sil (680.83 MPa) also showed higher and significantly different fatigue strength when compared to Uni adhe (584.55 MPa), while both were similar to Si-MDP (634.22 MPa) and Air-MDP (641.86 MPa). Conclusion: The association of mechanical and chemical approaches is essential for long-term bond strength and optimized mechanical behavior, being air-abrasion protocols and the use of silane and/or MDP-based primers suitable for zirconia repair protocols. It was found that relying solely on a universal adhesive was not as effective as other options available. Clinical significance: The surface treatment of repair protocols affects translucent zirconia's morphology. To enhance fatigue behavior in repaired monolithic zirconia, air abrasion is crucial. Exclusive use of a universal adhesive is less effective than other choices. A primer containing silane/MDP holds the potential for stable bond strength and optimized mechanical performance.

The enoyl reductase from Mycobacterium tuberculosis (MtInhA) was shown to be a major target for isoniazid, the most prescribed first-line anti-tuberculosis agent. The MtInhA (EC 1.3.1.9) protein catalyzes the hydride transfer from the 4S hydrogen of β-NADH to carbon-3 of long-chain 2-trans-enoyl thioester substrates (enoyl-ACP or enoyl-CoA) to yield NAD+ and acyl-ACP or acyl-CoA products. The latter are the long carbon chains of the meromycolate branch of mycolic acids, which are high-molecular-weight α-alkyl, β-hydroxy fatty acids of the mycobacterial cell wall. Here, stopped-flow measurements under single-turnover experimental conditions are presented for the study of the transient of reactants. Single-turnover experiments at various enzyme active sites were carried out. These studies suggested isomerization of the MtInhA:NADH binary complex in pre-incubation and positive cooperativity that depends on the number of enzyme active sites occupied by the 2-trans-dodecenoyl-CoA (DD-CoA) substrate. Stopped-flow results for burst analysis indicate that product release does not contribute to the rate-limiting step of the MtInhA-catalyzed chemical reaction. The bearings that the results presented herein have on function-based anti-tuberculosis drug design are discussed.

OM-85 is a bacterial lysate from common respiratory tract pathogens, with an excellent safety profile, widely used to prevent recurrent respiratory tract infections. Several studies have been reporting the immunomodulating properties and antiviral roles of OM-85. The COVID-19 pandemic, originating in 2019, has presented a significant global public health crisis. While effective vaccines have been developed, vaccination rates vary considerably, and numerous concerning viral variants continue to emerge. The challenge persists in creating early interventions to halt the progression of the disease to its severe stages. To examine the therapeutic effect of OM-85 after SARS-CoV-2 infection and compared to recombinant human (rhINF-β) we collected nasopharyngeal cells from COVID-19 patients. The cells were treated ex-vivo with OM-85 or hrINF-β and the response was analyzed after 24h for gene expression by real-time PCR. We found that OM-85 decreased the SARS-CoV-2 N1 gene expression and increased RIG-I (DDX58) in these cells. The expression of ACE2 was undetected in these samples. These data support the antiviral effect of OM-85 against SARS-CoV-2.

This study evaluated the mechanical behavior and risk of failure of three CAD-CAM crowns repaired with different resin composites through a three-dimensional (3D) finite element analysis. Three-dimensional models of different cusp-repaired (conventional nanohybrid, bulk-fill, and flowable resin composites) crowns made of zirconia, lithium disilicate, and CAD-CAM resin composite were designed, fixed at the cervical level, and loaded in 100 N at the working cusps, including the repaired one. The models were analyzed to determine the Maximum Principal and Maximum Shear stresses (MPa). Complementary, an in vitro shear bond strength test (n = 10) was performed to calculate the risk of failure for each experimental group. The stress distribution among the models was similar when considering the same restorative material. The crown material affected the stress concentration, which was higher for the ceramic models (±9 MPa for shear stress; ±3 MPa for tensile stress) than for the CAD-CAM composite (±7 MPa for shear stress; ±2 MPa for tensile stress). The shear bond strength was higher for the repaired CAD-CAM resin composite (±17 MPa) when compared to the ceramics (below 12 MPa for all groups), while the repair materials showed similar behavior for each substrate. The stress distribution is more homogenous for repaired resin composite crowns, and a flowable direct resin composite seems suitable to repair ceramic crowns with less risk of failure.

La fístula gástrica aguda es una de las principales complicaciones vinculadas a la gastrectomía vertical laparoscópica (GVL). Existen múltiples opciones terapéuticas para su resolución, siendo el tratamiento endoscópico mediante colocación de clips o stents uno de los más importantes. La aplicabilidad de cada método va a depender del tipo de fístula y del estado del paciente. Presentamos el caso de una mujer de 35 años, que desarrolla una fístula aguda posterior a una GVL. Se realiza tratamiento endoscópico con colocaciónn del sistema “over-the-scope clip” (Ovesco®) a nivel del orificio fistuloso, con posterior colocaciónn de stent metálico auto expandible. Palabras clave: fístula gástrica aguda, gastrectomía vertical laparoscópica, OVESCO, stent metálico auto expandible.

ABSTRACT Tuberculosis (TB) remains one of the leading causes of death due to a single pathogen. The emergence and proliferation of multidrug-resistant (MDR-TB) and extensively drug-resistant strains (XDR-TB) represent compelling reasons to invest in the pursuit of new anti-TB agents. The shikimate pathway, responsible for chorismate biosynthesis, which is a precursor of important aromatic compounds, is required for Mycobacterium tuberculosis growth. The enzyme 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase (MtbDAHPS) catalyzes the first step in the shikimate pathway and it is an attractive target for anti-tubercular agents. Here, we used a CRISPRi system to evaluate the DAHPS as a vulnerable target in M. tuberculosis. The silencing of aroG significantly reduces the M. tuberculosis growth in both rich medium and, especially, in infected murine macrophages. The supplementation with amino acids was only able to partially rescue the growth of bacilli, whereas the Aro supplement (aromix) was enough to sustain the bacterial growth at lower rates. This study shows that MtbDAHPS protein is vulnerable and, therefore, an attractive target to develop new anti-TB agents. In addition, the study contributes to a better understanding of the biosynthesis of aromatic compounds and the bacillus physiology. IMPORTANCE Determining the vulnerability of a potential target allows us to assess whether its partial inhibition will impact bacterial growth. Here, we evaluated the vulnerability of the enzyme 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase (DAHPS) from M. tuberculosis by silencing the DAHPS-coding aroG gene in different contexts. These results could lead to the development of novel and potent anti-tubercular agents in the near future.

Enoyl-ACP reductases (ENRs) are enzymes that catalyze the last step of the elongation cycle during fatty acid synthesis. In recent years, new bacterial ENR types were discovered, some of them with structures and mechanisms that differ from the canonical bacterial FabI enzymes. Here, we briefly review the diversity of structural and catalytic properties of the canonical FabI and the new FabK, FabV, FabL, and novel ENRs identified in a soil metagenome study. We also highlight recent efforts to use the newly discovered Fabs as targets for drug development and consider the complex evolutionary history of this diverse set of bacterial ENRs.

The propagation of sugarcane (Saccharum spp.) Requires seed with physiological and phytosanitary quality. The work was carried out with the objective of establishing a bank of sugarcane mother plants under semi-controlled conditions to guarantee the efficiency of in vitro propagation with plants free of Xanthomonas albilineans. A greenhouse was modified and the structure was remodeled, a Sarán shade mesh (50%) and a sprinkler irrigation system were placed. The plants were grown in plastic containers (20 m3 volume) with a mixture of cachaça compost and zeolite 3:1. Stems of cultivars C98-357, C97-445 and C86-156, without symptoms of leaf scald and with six months of culture, were cut into segments with a bud. Hydrothermal treatment was applied and subsequently the biostimulant VIUSID Agro® (0.8 ml l-1) before the buds planting. At three months of culture, a serological diagnosis was made to detect the presence of X. albilineans. The negative plants were treated with biostimulants and the response of the in vitro establishment was evaluated. Adequate plant growth was achieved under the conditions described. The establishment of a bank of sugarcane mother plants under semi-controlled conditions and its management guaranteed that microbial contamination and phenolic oxidation decreased in the in vitro establishment phase. The effectiveness of the hydrothermal treatment combined with the semi-controlled conditions and the management of the plants make it possible to reduce the incidence of X. albilineans.

The dihydroneopterin aldolase (DHNA, EC 4.1.2.25) activity of FolB protein is required for the conversion of 7,8-dihydroneopterin (DHNP) to 6-hydroxymethyl-7,8-dihydropterin (HP) and glycolaldehyde (GA) in the folate pathway. FolB protein from Mycobacterium tuberculosis (MtFolB) is essential for bacilli survival and represents an important molecular target for drug development. S8-functionalized 8-mercaptoguanine derivatives were synthesised and evaluated for inhibitory activity against MtFolB. The compounds showed IC50 values in the submicromolar range. The inhibition mode and inhibition constants were determined for compounds that exhibited the strongest inhibition. Additionally, molecular docking analyses were performed to suggest enzyme-inhibitor interactions and ligand conformations. To the best of our knowledge, this study describes the first class of MtFolB inhibitors.

Summary: Background: Gut microbiota-derived short-chain fatty-acid (SFCA) acetate protects mice against RSV A2 strain infection by increasing interferon-β production and expression of interferon-stimulated genes (ISGs). However, the role of SFCA in RSV infection using strains isolated from patients is unknown. Methods: We first used RSV clinical strains isolated from infants hospitalized with RSV bronchiolitis to investigate the effects of in vitro SCFA-acetate treatment of human pulmonary epithelial cells. We next examined whether SCFA-acetate treatment is beneficial in a mouse model of RSV infection using clinical isolates. We sought to investigate the relationship of gut microbiota and fecal acetate with disease severity among infants hospitalized with RSV bronchiolitis, and whether treating their respiratory epithelial cells with SCFA-acetate ex-vivo impacts viral load and ISG expression. We further treated epithelial cells from SARS-CoV-2 infected patients with SCFA-acetate. Findings: In vitro pre-treatment of A549 cells with SCFA-acetate reduced RSV infection with clinical isolates and increased the expression of RIG-I and ISG15. Animals treated with SCFA-acetate intranasally recovered significantly faster, with reduction in the RSV clinical isolates viral load, and increased lung expression of IFNB1 and the RIG-I. Experiments in RIG-I knockout A549 cells demonstrated that the protection relies on RIG-I presence. Gut microbial profile was associated with bronchiolitis severity and with acetate in stool. Increased SCFA-acetate levels were associated with increasing oxygen saturation at admission, and shorter duration of fever. Ex-vivo treatment of patients’ respiratory cells with SCFA-acetate reduced RSV load and increased expression of ISGs OAS1 and ISG15, and virus recognition receptors MAVS and RIG-I, but not IFNB1. These SCFA-acetate effects were not found on cells from SARS-CoV-2 infected patients. Interpretation: SCFA-acetate reduces the severity of RSV infection and RSV viral load through modulation of RIG-I expression. Funding: FAPERGS (FAPERGS/MS/CNPq/SESRS no. 03/2017 - PPSUS 17/2551-0001380-8 and COVID-19 20/2551-0000258-6); CNPq 312504/2017-9; CAPES) - Finance Code 001.

N-phenethylquinazolin-4-amines have emerged as potential Mycobacterium tuberculosis cytochrome bd oxidase inhibitors and attractive scaffolds in tuberculosis drug discovery programs. The classical two-step strategy of chlorination-amination to synthesize such structures presents several operational issues accompanied by variable results. This work reports an efficient one-pot protocol to access N-phenethylquinazolin-4-amines via silylation-amination mediated by hexamethyldisilazane. The products were obtained with excellent yields (84–99%) under one-pot solvent-free conditions.

Abstract Breast cancer is one of the leading types of cancer worldwide, and the search for new treatment options are crucial. Nonsteroidal anti-inflammatory drugs (NSAIDs) -specially ibuprofen and diclofenac-, have shown antitumoral effect against several types of cancer. The synthesis of organometallic compounds has shown significant improvements in pharmacological properties and efficacy of organic molecules. Two zinc II ternary complexes containing the NSAIDs diclofenac and ibuprofen and nicotinamide neutral linker (Nic) were obtained by the two-step solvent metalligand complexation method. The compounds Zn2(Diclof)4(Nic)2 (complex 1) and Zn2(Ibup)4(Nic)2 (complex 2) were tested in breast cancer cell lines (4T1, MCF-7 and MDA-MB-231) to evaluate their cytotoxicity, comparing to ibuprofen and diclofenac as controls. We found that both complex 1 and 2 exerted more than 60% reduction in 4T1 viability at 250µM, and complex 2 decreased cell viability at 250 µM and 137.5 µM in MCF-7 (34.35% and 26.42% reduction, respectively) and in MDA-MB-231 (57.2% and 22.88% reduction, respectively), all compared to controls. Complex 1 was selective only in MCF-7, and complex 2 was selective in both MCF-7 and MDA-MB-231. In summary, our data showed that the cytotoxic effect of complex 1 and 2 is increased comparing to their original NSAID in different breast cancer cell lines, highlighting their potential anti-tumoral activity.

ABSTRACT The epidemiological importance of mycobacterial species is indisputable, and the necessity to find new molecules that can inhibit their growth is urgent. The shikimate pathway, required for the synthesis of important bacterial metabolites, represents a set of targets for inhibitors of Mycobacterium tuberculosis growth. The aroA-encoded 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme catalyzes the sixth step of the shikimate pathway. In this study, we combined gene disruption, gene knockdown, point mutations (D61W, R134A, E321N), and kinetic analysis to evaluate aroA gene essentiality and vulnerability of its protein product, EPSPS, from Mycolicibacterium (Mycobacterium) smegmatis (MsEPSPS). We demonstrate that aroA-deficient cells are auxotrophic for aromatic amino acids (AroAAs) and that the growth impairment observed for aroA-knockdown cells grown on defined medium can be rescued by AroAA supplementation. We also evaluated the essentiality of selected MsEPSPS residues in bacterial cells grown without AroAA supplementation. We found that the catalytic residues R134 and E321 are essential, while D61, presumably important for protein dynamics and suggested to have an indirect role in catalysis, is not essential under the growth conditions evaluated. We have also determined the catalytic efficiencies (Kcat/Km) of recombinant wild-type (WT) and mutated versions of MsEPSPS (D61W, R134A, E321N). Our results suggest that drug development efforts toward EPSPS inhibition may be ineffective if bacilli have access to external sources of AroAAs in the context of infection, which should be evaluated further. In the absence of AroAA supplementation, aroA from M. smegmatis is essential, its essentiality is dependent on MsEPSPS activity, and MsEPSPS is vulnerable. IMPORTANCE We found that cells from Mycobacterium smegmatis, a model organism safer and easier to study than the disease-causing mycobacterial species, when depleted of an enzyme from the shikimate pathway, are auxotrophic for the three aromatic amino acids (AroAAs) that serve as building blocks of cellular proteins: l-tryptophan, l-phenylalanine, and l-tyrosine. That supplementation with only AroAAs is sufficient to rescue viable cells with the shikimate pathway inactivated was unexpected, since this pathway produces an end product, chorismate, that is the starting compound of essential pathways other than the ones that produce AroAAs. The depleted enzyme, the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), catalyzes the sixth step of shikimate pathway. Depletion of this enzyme inside cells was performed by disrupting or silencing the EPSPS-encoding aroA gene. Finally, we evaluated the essentiality of specific residues from EPSPS that are important for its catalytic activity, determined with experiments of enzyme kinetics using recombinant EPSPS mutants.

Presentamos el caso de una paciente de sexo femenino de 40 años que consultó por astenia, adinamia, mareos y disnea progresiva de diez meses de evolución agregando en los últimos cuatro meses disfagia intermitente para sólidos. La radiografía esofágica con bario evidenció la presencia de una estenosis subcricoidea con buen pasaje distal y la videogastroscopía demostró inmediatamente por debajo del cricofaríngeo una membrana fibrosa estenosante. Se realizó tratamiento con hierro vía oral y reiteradas sesiones de dilatación con balón que lograron la resolución de los síntomas. El síndrome de Plummer-Vinson es una entidad poco frecuente caracterizada por la tríada anemia ferropénica, disfagia y membrana esofágica alta.

Tuberculosis remains a global health problem that affects millions of people around the world. Despite recent efforts in drug development, new alternatives are required. Herein, a series of 27 N-(4-(benzyloxy)benzyl)-4-aminoquinolines were synthesized and evaluated for their ability to inhibit the M. tuberculosis H37Rv strain. Two of these compounds exhibited minimal inhibitory concentrations (MICs) similar to the first-line drug isoniazid. In addition, these hit compounds were selective for the bacillus with no significant change in viability of Vero and HepG2 cells. Finally, chemical stability, permeability and metabolic stability were also evaluated. The obtained data show that the molecular hits can be optimized aiming at the development of drug candidates for tuberculosis treatment.

The global epidemic of tuberculosis (TB) imposes a sustained epidemiologic vigilance and investments in research by governments. Mycobacterium tuberculosis, the main causative agent of TB in human beings, is a very successful pathogen, being the main cause of death in the population among infectious agents. In 2018, ~10 million individuals were contaminated with this bacillus and became ill with TB, and about 1.2 million succumbed to the disease. Most of the success of the M. tuberculosis to linger in the population comes from its ability to persist in an asymptomatic latent state into the host and, in fact, the majority of the individuals are unaware of being contaminated. Even though TB is a treatable disease and is curable in most cases, the treatment is lengthy and laborious. In addition, the rise of resistance to first-line anti-TB drugs elicits a response from TB research groups to discover new chemical entities, preferably with novel mechanisms of action. The pathway to find a new TB drug, however, is arduous and has many barriers that are difficult to overcome. Fortunately, several approaches are available today to be pursued by scientists interested in anti-TB drug development, which goes from massively testing chemical compounds against mycobacteria, to discovering new molecular targets by genetic manipulation. This review presents some difficulties found along the TB drug development process and illustrates different approaches that might be used to try to identify new molecules or targets that are able to impair M. tuberculosis survival.

A exploração de erva-mate é uma das atividades agrícolas mais antigas na região do Planalto Norte Catarinense. Além do vínculo cultural, representa fonte de renda e empregabilidade para os agricultores. O presente trabalho destina-se ao estudo da avaliação econômica de um adensamento aleatório de erva-mate em um plantio nativo. A produtividade do erval foi estimada em três sistemas de colheita: em sistema anual, em sistema bienal (Bienal 1) e em sistema intercalado, onde cada metade do erval é colhida a cada dois anos intercalados (Bienal 2). Para cada sistema de colheita foram calculados o payback, a razão receitas/custos, o custo médio de produção, o valor presente líquido (VPL), o valor anual equivalente (VAE), o valor presente líquido infinito (VPL∞) e a taxa interna de retorno (TIR). Após processados todos os dados, o sistema anual foi claramente o que apresentou o payback mais curto, de 1,66 ano, mostrando que nesse sistema o retorno do investimento inicial será mais rápido, pois evita a perda natural de folhas. O sistema de colheita anual também apresentou melhor VPL e maior TIR, de 76%, demonstrando melhor viabilidade econômica.

The substrate used in the phase of acclimatization is determinant to reach quality plants. They can be solid and porous materials of natural or synthetic origin that alone or mixture guarantee a suitable growth of the plants under environmental controlled conditions. The aim of this work takes root in the evaluation of three variants of substrate for this phase: 80 % of compost and 20 % of zeolite (I); 50 % of the treatment I more 50 % of solid residue obtained of the biogas from vinaza (II) and 100 % of the solid residue of the biogas (III). There was characterized the chemical composition of the substrate. The following evaluations were made: survival, number of dead plants and number of leaves, to the last evaluation were added: root length, stem height and diameter, leaf length +1, number of total leaves, pests and diseases present. The solid residue of the biogas formed from vinaza, presented a top content of organic matter and total macroelements. This residue allows the growth of the in vitro plants and is feasible to use it as substrate only or mixed with the compost.

Tuberculosis has been described as a global health crisis since the 1990s, with an estimated 1.4 million deaths in the last year. Herein, a series of 20 1H-indoles were synthesized and evaluated as in vitro inhibitors of Mycobacterium tuberculosis (Mtb) growth. Furthermore, the top hit compounds were active against multidrug-resistant strains, without cross-resistance with first-line drugs. Exposing HepG2 and Vero cells to the molecules for 72 h showed that one of the evaluated structures was devoid of apparent toxicity. In addition, this 3-phenyl-1H-indole showed no genotoxicity signals. Finally, time-kill and pharmacodynamic model analyses demonstrated that this compound has bactericidal activity at concentrations close to the Minimum Inhibitory Concentration, coupled with a strong time-dependent behavior. To the best of our knowledge, this study describes the activity of 3-phenyl-1H-indole against Mtb for the first time.

Tuberculosis (TB) has been described as a global health crisis since the second half of the 1990s. Mycobacterium tuberculosis (Mtb), the etiologic agent of TB in humans, is a very successful pathogen, being the main cause of death in the population among infectious agents. In 2019, it was estimated that around 10 million individuals were contaminated by this bacillus and about 1.2 million succumbed to the disease. In recent years, our research group has reported the design and synthesis of quinoline derivatives as drug candidates for the treatment of TB. These compounds have demonstrated potent and selective growth inhibition of drug-susceptible and drug-resistant Mtb strains. Herein, a new synthetic approach was established providing efficient and rapid access (15 min) to a series of 4-alkoxy-6-methoxy-2-methylquinolines using ultrasound energy. The new synthetic protocol provides a simple procedure utilizing an open vessel system that affords the target products at satisfactory yields (45–84%) and elevated purities (≥95%). The methodology allows the evaluation of a larger number of molecules in assays against the bacillus, facilitating the determination of the structure–activity relationship with a reduced environmental cost.

Gastrointestinal fistulae are defined as abnormal communications between hollow organs or between a hollow organ and the skin. Fistulas generate a high morbimortality. Between 80 and 90% are secondary to a surgical procedure, and between 10 and 20% are spontaneous (related to radiotherapy, inflammatory bowel disease, cancer, among others). Sepsis represents the main cause of death among those patients who develop a gastrointestinal fistula regardless of the cause of origin of the fistula. The goal of this article is to present a first case in Uruguay of a high output duodenocutaneous fistula, and describe its resolution, which included a combined medical-surgical-endoscopic approach.

Introducción: el cáncer colorrectal (CCR) es la tercera causa de muerte por cáncer en hombres y la segunda causa de muerte por cáncer en mujeres de nuestro país. Se ha sugerido que los pacientes con hernias de pared abdominal tendrían más posibilidades de asociar CCR, lo que ha llevado a recomendar por parte de numerosas sociedades científicas la realización de videocolonoscopía (VCC) para búsqueda de CCR previo a la resolución quirúrgica de las hernias. Estudios más recientes han cuestionado esta indicación, no recomendando la realización de VCC en pacientes con hernias de la pared abdominal sin otra sintomatología. Objetivo: Específico. Establecer la prevalencia de CCR y lesiones preneoplásicas en pacientes en valoración preoperatoria de hernias de pared abdominal. Secundario. Establecer si existe asociación estadística entre CCR y la aparición de hernias abdominales. Material y método: se realizó un estudio retrospectivo de casos controles que incluyó a pacientes que concurrieron en el período comprendido entre enero de 2006 y febrero de 2014 al servicio de Endoscopía Digestiva del Hospital de Clínicas. Se definieron como casos los pacientes a quienes se les había indicado una VCC previa a la reparación quirúrgica de su hernia de pared abdominal y se definieron como controles al grupo de pacientes que concurrió al mismo servicio en el mismo período a realizarse VCC para tamizaje de cáncer de colon. Resultados: en el grupo de casos se incluyeron 225 pacientes. En este, 55 VCC (24,4%) fueron incompletas por diversos motivos (56,4% por intolerancia). Se encontraron dos pacientes (0,9%) con cáncer de colon (uno cáncer de colon ascendente y el otro cáncer de colon descendente). En el grupo control se incluyeron 230 pacientes. En este grupo, un paciente (0,43%) presentó cáncer de colon ascendente; 21 VCC (9,1%) fueron parciales debido a intolerancia en el mayor porcentaje de los casos. Discusión: está demostrada la relación entre patologías que aumentan la presión intraabdominal y la posterior aparición de hernias, por lo que se podría pensar que un CCR sintomático pueda desencadenar la aparición de las mismas; sin embargo, no existe fundamento que sustente que un CCR asintomático pueda provocar lo mismo. En este estudio no hubo diferencias significativas en la frecuencia de CCR entre el grupo de casos y controles. Conclusiones: la decisión de realizar o no una VCC debería seguir los lineamientos habituales recomendados por las sociedades científicas respecto al screening de CCR y no basarse en la sola presencia de las hernias para realizar dicho estudio.

Roughly a third of the world’s population is estimated to have latent Mycobacterium tuberculosis infection, being at risk of developing active tuberculosis (TB) during their lifetime. Given the inefficacy of prophylactic measures and the increase of drug-resistant M. tuberculosis strains, there is a clear and urgent need for the development of new and more efficient chemotherapeutic agents, with selective toxicity, to be implemented on patient treatment. The component enzymes of the shikimate pathway, which is essential in mycobacteria and absent in humans, stand as attractive and potential targets for the development of new drugs to treat TB. This review gives an update on published work on the enzymes of the shikimate pathway and some insight on what can be potentially explored towards selective drug development.

The emergence of strains of Mycobacterium tuberculosis resistant to isoniazid (INH) has underscored the need for the development of new anti-tuberculosis agents. INH is activated by the mycobacterial katG-encoded catalase-peroxidase, forming an acylpyridine fragment that is covalently attached to the C4 of NADH. This isonicotinyl-NAD adduct inhibits the activity of 2-trans-enoyl-ACP(CoA) reductase (InhA), which plays a role in mycolic acid biosynthesis. A metal-based INH analog, Na3[FeII(CN)5(INH)]·4H2O, IQG-607, was designed to have an electronic redistribution on INH moiety that would lead to an intramolecular electron transfer to bypass KatG activation. HPLC and EPR studies showed that the INH moiety can be oxidized by superoxide or peroxide yielding similar metabolites and isonicotinoyl radical only when associated to IQG-607, thereby supporting redox-mediated drug activation as a possible mechanism of action. However, IQG-607 was shown to inhibit the in vitro activity of both wild-type and INH-resistant mutant InhA enzymes in the absence of KatG activation. IQG-607 given by the oral route to M. tuberculosis-infected mice reduced lung lesions. Experiments using early and late controls of infection revealed a bactericidal activity for IQG-607. HPLC and voltammetric methods were developed to quantify IQG-607. Pharmacokinetic studies showed short half-life, high clearance, moderate volume of distribution, and low oral bioavailability, which was not altered by feeding. Safety and toxic effects of IQG-607 after acute and 90-day repeated oral administrations in both rats and minipigs showed occurrence of mild to moderate toxic events. Eight multidrug-resistant strains (MDR-TB) were resistant to IQG-607, suggesting an association between katG mutation and increasing MIC values. Whole genome sequencing of three spontaneous IQG-607-resistant strains harbored katG gene mutations. MIC measurements and macrophage infection experiments with a laboratorial strain showed that katG mutation is sufficient to confer resistance to IQG-607 and that the macrophage intracellular environment cannot trigger the self-activation mechanism. Reduced activity of IQG-607 against an M. tuberculosis strain overexpressing S94A InhA mutant protein suggested both the need for KatG activation and InhA as its target. Further efforts are suggested to be pursued toward attempting to translate IQG-607 into a chemotherapeutic agent to treat tuberculosis.

Introducción: la video cápsula endoscópica (VCE) y la enteroscopía de doble balón (EDB) han cambiado radicalmente el diagnóstico y tratamiento de las patologías del intestino delgado (ID). Objetivo: valorar la utilidad diagnóstica y terapéutica de la EDB en enfermedades del ID. Pacientes, material y método: se realizó un estudio retrospectivo, descriptivo, de las primeras 20 EDB realizadas en nuestro servicio de endoscopía. Los pacientes fueron referidos por sospecha de patología del ID y contaban con estudios endoscópicos o imagenológicos previos. Se utilizó un videoenteroscopio EN-450, Fujinon, de 2.000 mm de longitud y sobretubo TS-12140 Fujinon. Resultados: se realizaron 20 EDB en 19 pacientes (14 hombres con edad promedio de 52,2 años y 5 mujeres con edad promedio de 58,6 años). El abordaje oral fue de elección en 15 procedimientos y el anal en cuatro, un paciente requirió doble abordaje. La indicación más frecuente fue la búsqueda de sangrado intestinal de origen desconocido y el hallazgo más común fueron las angiodisplasias, que fueron tratadas con coagulación con gas argón. Conclusiones: la EDB es una herramienta útil y necesaria para el diagnóstico y tratamiento de las patologías del ID, pudiendo brindar a nuestros pacientes una solución terapéutica que hasta hace pocos años no era posible en nuestro país.

M. tuberculosis and parasites of the genus Leishmania present the type II fatty acid biosynthesis system (FASII). The pentacyano(isoniazid)ferrate(II) compound, named IQG-607, inhibits the enzyme 2-trans-enoyl-ACP(CoA) reductase from M. tuberculosis, a key component in the FASII system. Here, we aimed to evaluate the inhibitory activity of IQG-607 against promastigote and amastigote forms of Leishmania (Viannia) braziliensis isolated from patients with different clinical forms of L. braziliensis infection, including cutaneous, mucosal and disseminated leishmaniasis. Importantly, IQG-607 inhibited the proliferation of three different isolates of L. braziliensis promastigotes associated with cutaneous, mucosal and disseminated leishmaniasis. The IC50 values for IQG-607 ranged from 32 to 75 μM, for these forms. Additionally, IQG-607 treatment decreased the proliferation of intracellular amastigotes in infected macrophages, after an analysis of the percentage of infected cells and the number of intracellular parasites/100 cells. IQG-607 reduced from 58% to 98% the proliferation of L. braziliensis from cutaneous, mucosal and disseminated strains. Moreover, IQG-607 was also evaluated regarding its potential toxic profile, by using different cell lines. Cell viability of the lineages Vero, HaCat and HepG2 was significantly reduced after incubation with concentrations of IQG-607 higher than 2 mM. Importantly, IQG-607, in a concentration of 1 mM, did not induce DNA damage in HepG2 cells, when compared to the untreated control group. Future studies will confirm the mechanism of action of IQG-607 against L. braziliensis.

Cutaneous leishmaniasis (CL) is the most common clinical form of American tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis. CL is associated with a strong Th1 immune response. This exacerbated inflammatory response is correlated with severity of disease and delays the healing time of the ulcer. The fourth-generation immucillin derivative (DI4G), a potent inhibitor of purine nucleoside phosphorylase, has been proposed as a promising agent in the treatment of diseases associated with T cell activation. Herein, we evaluated the in vitro immunomodulatory activity of DI4G in cells of patients presenting with CL. Peripheral blood mononuclear cells (PBMC) from CL patients were stimulated with soluble leishmania antigen (SLA), in the presence or absence of DI4G, and IFN-γ, TNF, CXCL9, and CXCL10 levels were determined by ELISA. Lymphocyte proliferation in the presence or absence of DI4G was also evaluated, using flow cytometry. DI4G was able to decrease (p

FitoMas-E increases and accelerates the germination of the seeds, stimulates the development of roots, stems, leaves and improves the nutrition of plants.The objective of this work was to evaluate the effect of FitoMas-E on the in vitro rooting of sugarcane cultivars ‘CP52-43’, ‘C87-51’ and ‘C1051-73’. A completely randomized experimental design was used with four treatments, three concentrations of FitoMas-E (0.5, 1.0 and 1.5 ml l-1) and indoleacetic acid (IAA) 1.3 mg l-1 as control in the liquid culture medium, with five repetition. At 15 days of culture the number of rooted shoots, height, leaves number and length of roots were evaluated. In the ex vitro acclimatization stage, its were quantified the number of plants with root, leaves and roots number per plant and it was measured the height after 45 days of transplanted. The results showed that the Fitomas-E in the cultivars 'CP52-43' and 'C87-51' achieved a number of shoots with a root similar to the control and in 'C1051-73' it exceeded it with the concentration of 0.5 ml l-1 of this biostimulant. Leaf height, leaves number and root length reached values significantly higher than control, with 1.0 ml l-1 phytostimulant, except for 'CP52-43' where similar root length was achieved among treatments. In the ex vitro acclimatization stage the in vitro plants rooted with the FitoMas-E achieved the required quality parameters, exceeding the controls for the variables height, number of roots and length of the longest root. Among genotypes there were significant differences for all cultivars. Keywords: in vitro culture, micropropagation, Saccharum spp.

Las fístulas gastrointestinales se definen como comunicaciones anormales entre órganos huecos o entre un órgano hueco y la piel. Generan una alta morbimortalidad en quienes la padecen. Entre el 80 y 90% son secundarias a un acto quirúrgico y entre un 10 y 20% son espontáneas (relacionadas con radioterapia, enfermedad inflamatoria intestinal, neoplasias, entre otras). La sepsis representa la principal causa de muerte entre aquellos pacientes que desarrollan una fístula gastrointestinal independientemente de la causa de origen de la misma. El objetivo de este artículo es presentar el primer caso en Uruguay de una fístula duodeno-cutánea de alto gasto cuya resolución incluyó un tratamiento combinado médico-quirúrgico-endoscópico.

Morinda royoc L. is a medicinal plant which has identified numerous secondary metabolites important for medical and pharmaceutical industry. The use of in vitro culture techniques could contribute to the production of these. The aim of this work was to multiply M. royoc using Temporary Immersion System (TIS). It was used TIS of 1000 ml capacity. Each contained 250 ml MS medium with 4.4 μM benzyladenine (BA) and 2.9 μM indole acetic acid (IAA). The SIT were inoculated with 30 individual explants (shoot tips and nodal segments). It was determined the effect of the immersion frequency (two, four and six immersions of two minutes per day) and the type of explants (shoot tips, nodal segments) on the multiplication of shoots and biomass production. It was found that with four and six immersions per day the highest values of multiplication coefficient and shoot length were obtained. The maximum biomass production was achieved with six immersions per day. No hyperhidricity symptoms were observed in shoots. It was noted that the nodal segments produced more shoots per explant, increased multiplication coefficient and biomass than the apex, while the latter resulted in longer shoots. Keywords: micropropagation, shoots multiplication

Morinda royoc L., is a specie threatened by over collection due to its importance as medicinal plant. The in vitro propagation of M. royoc may help to solve the increasing demand of stock plants for field cultivation and also would contribute with in vitro conservation strategies and further breeding programs. The aim was to regenerate in vitro plants of M. royoc from shoot tips and nodal explants. Shoot cultures were established starting from tips and nodal segments from greenhouse grown plants. In the multiplication phase the highest multiplication rate was achieved when the culture medium was supplemented with 4.4 µM 6-benzylaminopurine (BA) and 2.9 µM indole-3-acetic acid (IAA). Addition of IAA to rooting medium influenced the quality of the plantlets and the survival rate after transplant to acclimatization stage. Survival 96.4% was achieved in plants cultured in the medium containing 2.9 µM IAA. The in vitro regeneration of M. royoc plants could be used either for the commercial clonal propagation of the species or for future studies on the production of secondary metabolites for pharmaceutical use given the medicinal properties of the species. Keywords: acclimatization, micropropagation, rooting, shoots multiplication

The title compound, C12H10N2O, is approximately planar. The angle between the quinoline and 4,5-dihydrooxazole ring systems is 11.91 (12)°. The molecules pack into a herringbone array with no significant π–π interactions. The dihydrooxazole N and O atoms are disordered over two positions, with almost equal site occupancy factors.

In the title compound, C15H12F3N3, the pyrazolo[1,5-a]pyrimidine system ring is essentially planar with a maximum deviation from the mean plane of 0.014 (1) Å. The 4-tolyl group makes a dihedral angle of 14.1 (1)° with the pyrazolo[1,5-a]pyrimidine ring system. The crystal packing is stabilized mainly by van der Waals forces.

The propagation of Heliconia sp. in Cuba is conceived by applying traditional methods, which are mainly based on sowing or planting rhizomes. Having a protocol for the in vitro culture would increase the yield and quality of the plants obtained. The aim of this study was to establish a protocol for in vitro propagation of H. standleyi. Experiments were conducted in each of the stages from establishment to acclimatization. The in vitro propagation of H. standleyi was achieved. For in vitro establishment, 2% of sodium hypochlorite, 20 min of disinfection and liquid culture medium were used. When using 2.0 mg.l-1 6-BAP and 0.65 mg.l-1 IAA, in the multiplication stage in semisolid culture medium, a 4.6 multiplication coefficient was obtained. It was demonstrated that explants should be higher than 3.0 cm to be transferred to rooting stage. A determining factor in the acclimatization stage to achieve a greater plant survival was the initial height of the explants (higher than 5.0 cm) to be sent to field after 45 days of culture. Key words: acclimatization, micropropagation

Gerbera is one of the horticultural crops of great demand on the Cuban local market, but its exploitation is limited because with the traditional multiplication methods established, it is not possible to comply with the demands of the “seeds”. This work was carried out at the biofactory of Las Flores de Servicios Comunales”, with the objective of establishing a methodology for the in vitro commercial propagation of Gerbera. Culture media and explant management in the different micropropagation phases were studied. The results obtained showed that with sodium hypochlorite at 0.5% during 10 minutes, a high disinfection of the shoot tips was achieved. With the combination of 6-bencilaminepurine (1.0 mg-l-1) and giberrelic acid (0.1 mg.l-1) in the culture medium, it was possible to increase the number of shoots per explant during establishment. In the multiplication phase, the best results were obtained with a combination of 6-BAP (2.0 mg.l-1) with AIA (0.65 and 1.3 mg.l-1) subculturing the explants greater than 1.0 cm individually in semisolid culture medium. A significant influence on the number of roots and growth of the explants was achieved adding indolacetic acid to the rooting medium and using for the subculture, explants greater than 3.0 cm. The quality of the explants influenced significantly in the acclimatization phase, demonstrating that the plants rooted in vitro should be 3.0 cm in height. Key words: explants, disinfection, shoot tip, culture medium