Patterns of Diversity and Humoral Immunogenicity for HIV-1 Antisense Protein (ASP).

HIV-1 has an antisense gene overlapping env that encodes the ASP protein. ASP functions are still unknown, but it has been associated with gp120 in the viral envelope and membrane of infected cells, making it a potential target for immune response. Despite this, immune response patterns against ASP are poorly described and can be influenced by the high genetic variability of the env gene. To explore this, we analyzed 100k HIV-1 ASP sequences from the Los Alamos HIV sequence database using phylogenetic, Shannon entropy (Hs), and logo tools to study ASP variability in worldwide and Brazilian sequences from the most prevalent HIV-1 subtypes in Brazil (B, C, and F1). Data obtained in silico guided the design and synthesis of 15-mer overlapping peptides through spot synthesis on cellulose membranes. Peptide arrays were screened to assess IgG and IgM responses in pooled plasma samples from HIV controllers and individuals with acute or recent HIV infection. Excluding regions with low alignment accuracy, several sites with higher variability (Hs > 1.5) were identified among the datasets (25 for worldwide sequences, 20 for Brazilian sequences). Among sites with Hs < 1.5, sequence logos allowed the identification of 23 other sites with subtype-specific signatures. Altogether, amino acid variations with frequencies > 20% in the 48 variable sites identified were included in 92 peptides, divided into 15 sets, representing near full-length ASP. During the immune screening, the strongest responses were observed in three sets, one in the middle and one at the C-terminus of the protein. While some sets presented variations potentially associated with epitope displacement between IgG and IgM targets and subtype-specific signatures appeared to impact the level of response for some peptides, signals of cross-reactivity were observed for some sets despite the presence of B/C/F1 signatures. Our data provides a map of ASP regions preferentially targeted by IgG and IgM responses. Despite B/C/F1 subtype signatures in ASP, the amino acid variation in some areas preferentially targeted by IgM and IgG did not negatively impact the response against regions with higher immunogenicity.

Optimization of enhanced oil recovery using ASP solution.

Many studies have been conducted to focused on developing an optimal alkali/surfactant/polymer (ASP) composition to increase the recovered fraction of oil in reservoirs that have already undergone water injection. To analyze the effect of alkali (Na2CO3), surfactant (lauryl sodium sulfate), and polymer (commercial xanthan gum) concentration on oil recovery, a complete factorial experimental design was performed with combinations of three variables (alkali, surfactant, and polymer) and three central point replications (2³ + 3). The experiments were carried out on a core holder using rock samples from the Botucatu formation. The simulated oil reservoirs have an average permeability of 348 mD and a temperature of 60 °C. The crude oil was acquired from the Carmópolis field, with 25.72 °API. Synthetic production water containing 40,000 mg L-1 of NaCl and 13,000 mg L-1 of Na2SO4 was injected through an HPLC pump to saturate the rock samples and to recover the oil in the secondary step. From the experimental results, it was verified that the surfactant and polymer concentrations are the most statistically significant independent variables and that first-order interactions are not statistically significant for the process. The oil recovery factors in the secondary stage ranged between 30 and 36 % of the OOIP, which are within the range reported in the literature. The optimal composition of the ASP fluid obtained a recovered fraction of oil of 62 % in the advanced step. Other combinations reported in the literature used higher concentrations of alkali, surfactant, and polymer with lower recoveries and higher cost in the injection design. Thus, the present study highlights the necessity to investigate the performance of each component of the ASP solution. In addition, the results obtained in this study are very attractive for possible full-scale applications.

Effect on cell survival and cytoophidium assembly of the adRP-10-related IMPDH1 missense mutation Asp226Asn.

Introduction: Inosine monophosphate dehydrogenase 1 (IMPDH1) is a critical enzyme in the retina, essential for the correct functioning of photoreceptor cells. Mutations in IMPDH1 have been linked to autosomal dominant retinitis pigmentosa subtype 10 (adRP-10), a genetic eye disorder. Some of these mutations such as the Asp226Asn (D226N) lead to the assembly of large filamentous structures termed cytoophidia. D226N also gives IMPDH1 resistance to feedback inhibition by GDP/GTP. This study aims to emulate the adRP-10 condition with a long-term expression of IMPDH1-D226N in vitro and explore cytoophidium assembly and cell survival. We also assessed whether the introduction of an additional mutation (Y12C) to disrupt the cytoophidium has an attenuating effect on the toxicity caused by the D226N mutation. Results: Expression of IMPDH1-D226N in HEp-2 cells resulted in cytoophidium assembly in ∼70% of the cells, but the presence of the Y12C mutation disrupted the filaments. Long-term cell survival was significantly affected by the presence of the D226N mutation, with a decrease of ∼40% in the cells expressing IMPDH1-D226N when compared to IMPDH1-WT; however, survival was significantly recovered in IMPDH1-Y12C/D226N, with only a ∼10% decrease when compared to IMPDH1-WT. On the other hand, the IMPDH1 expression level in the D226N-positive cells was <30% of that of the IMPDH1-WT-positive cells and only slightly higher in the Y12C/D226N, suggesting that although cell survival in Y12C/D226N was recovered, higher expression levels of the mutated IMPDH1 were not tolerated by the cells in the long term. Conclusion: The IMPDH1-D226N effect on photoreceptor cell survival may be the result of a sum of problems: nucleotide unbalance plus a toxic long-life cytoophidium, supported by the observation that by introducing Y12C in IMPDH1 the cytoophidium was disrupted and cell survival significantly recovered, but not the sensibility to GDP/GTP regulation since higher expression levels of IMPDH1-D226N were not tolerated.

A New Approach to Inhibiting Triple-Negative Breast Cancer: In Vitro, Ex Vivo and In Vivo Antiangiogenic Effect of BthTx-II, a PLA2-Asp-49 from Bothrops jararacussu Venom.

Phospholipases A2 (PLA2) represent a superfamily of enzymes widely distributed in living organisms, with a broad spectrum of pharmacological activities and therapeutic potential. Anti-angiogenic strategies have become one of the main tools in fighting cancer. In this sense, the present work reports the inhibition of tumor angiogenesis induced by Asp-49 BthTX-II using in vitro, ex vivo and in vivo approaches. We demonstrate that BthTx-II inhibited cell adhesion, proliferation, and migration of human umbilical vein endothelial cells (HUVEC), as well as caused a reduction in the levels of endothelial growth factor (VEGF) during in vitro angiogenesis assays. BthTx-II was also able to inhibit the sprouting angiogenic process, by the ex vivo germination assay of the aortic ring; in addition, this toxin inhibited the migration and proliferation of HUVEC in co-culture with triple-negative breast cancer cells (e.g., MDA-MB-231 cells). Finally, in vivo tumor suppression and anti-angiogenic activities were analyzed using MDA-MB-231 cells with Matrigel injected into the chorioallantoic membrane of chicken embryo (CAM) for 7 days treatment with BthTx-II, showing a considerable reduction in vessel caliber, on the size and weight of tumors. Together, these results suggest an important antiangiogenic and antitumor role for BthTx-II, as a potential prototype for the development of new tools and antitumor drugs in cancer therapy.

Ultrastructural changes in methicillin-resistant Staphylococcus aureus (MRSA) induced by a novel cyclic peptide ASP-1 from Bacillus subtilis: A scanning electron microscopy (SEM) study / Cambios ultraestructurales en Staphylococcusaureus resistente a meticilina (SARM) inducidos por un nuevo péptido cíclico ASP-1 de Bacillussubtilis: un estudio con microscopio electrónico de barrido (MEB)

ABSTRACT Increasing antimicrobial resistance amongStaphylococcus aureusnecessitates a new antimicrobial with a different site of action. We have isolated a novel cyclic peptide-1 (ASP-1) fromBacillussubtiliswith potent activity against methicillin-resistantS. aureus(MRSA) at a minimum inhibitory concentration (MIC) of 8-64μg/ml. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of ASP-1 treated cells ofS. aureusATCC 29213 and an MRSA clinical isolate at MICs, with damages to the cell wall, membrane lysis and probable leakage of cytoplasmic contents at minimum bactericidal concentrations. The ultrastructure alterations induced by ASP-1 have also been compared with those of oxacillin-treated MRSA cells at its MIC using scanning electron microscopy.

RESUMEN El incremento de la resistencia antimicrobiana entre los tipos deS. aureusexige un nuevo agente antimicrobiano con un sitio de acción diferente. Aislamos un nuevo péptido cíclico (ASP-1) deBacillussubtiliscon potente actividad frente aS. aureusresistente a meticilina (SARM) en una concentración inhibitoria mínima (CIM) de 8-64μg/ml. Las micrografías obtenidas con microscopio electrónico de barrido mostraron cambios drásticos en la arquitectura celular de las células deS. aureusATCC 29213 tratadas con ASP-1, y un aislamiento clínico de SARM a la CIM, con daños a la pared celular, lisis de la membrana y probable fuga de contenido citoplasmático a concentraciones bactericidas mínimas. Comparamos también, las alteraciones de la ultraestructura inducidas por ASP-1 con las de células de SARM tratadas con oxacilina a su CIM, utilizando microscopio electrónico de barrido.

ASP-Enzymosomes with Saccharomyces cerevisiae Asparaginase II Expressed in Pichia pastoris: Formulation Design and In Vitro Studies of a Potential Antileukemic Drug.

The bacterial enzyme asparaginase is the main treatment option for acute lymphoblastic leukemia. However, it causes side effects, such as immunological reactions, and presents undesirable glutaminase activity. As an alternative, we have been studying asparaginase II from Saccharomyces cerevisiae, coded by ASP3 gene, which was cloned and expressed in Pichia pastoris. The recombinant asparaginase (ASP) presented antileukemic activity and a glutaminase activity 100 times lower in comparison to its asparaginase activity. In this work, we describe the development of a delivery system for ASP via its covalent attachment to functionalized polyethylene glycol (PEG) polymer chains in the outer surface of liposomes (ASP-enzymosomes). This new delivery system demonstrated antiproliferative activity against K562 (chronic myeloid leukemia) and Jurkat (acute lymphocytic leukemia) cell lines similar to that of ASP. The antiproliferative response of the ASP-enzymosomes against the Jurkat cells suggests equivalence to that of the free Escherichia coli commercial asparaginase (Aginasa®). Moreover, the ASP-enzymosomes were stable at 4 °C with no significant loss of activity within 4 days and retained 82% activity up to 37 days. Therefore, ASP-enzymosomes are a promising antileukemic drug.

Epidemiological aspects of hereditary fructose intolerance: A database study.

Hereditary fructose intolerance (HFI) is an inborn error of fructose metabolism of autosomal recessive inheritance caused by pathogenic variants in the ALDOB gene that lead to aldolase B deficiency in the liver, kidneys, and intestine. Patients manifest symptoms, such as ketotic hypoglycemia, vomiting, nausea, in addition to hepatomegaly and other liver and kidney dysfunctions. The treatment consists of a fructose-restricted diet, which results in a good prognosis. To analyze the distribution of ALDOB variants described in patients and to estimate the prevalence of HFI based on carrier frequency in the gnomAD database, a systematic review was conducted to assess ALDOB gene variants among patients with HFI. The prevalence of HFI was estimated from the carrier frequency of variants described in patients, as well as rare variants predicted as pathogenic by in silico tools. The p.(Ala150Pro) and p.(Ala175Asp) variants are the most frequent and are distributed worldwide. However, these variants have particular distribution patterns in Europe. The analysis of the prevalence of HFI showed that the inclusion of rare alleles predicted as pathogenic is a more informative approach for populations with few patients. The data show that HFI has a wide distribution and an estimated prevalence of ~1:10,000.

Phenotypic characterization and predictive analysis of p.Asp47Asn LDL receptor mutation associated with Familial Hypercholesterolemia in a Chilean population.

BACKGROUND: Familial hypercholesterolemia (FH) is an inherited disorder mainly caused by mutations in the LDL receptor (LDL-R) and characterized by elevation of low-density lipoprotein cholesterol (LDL-C) levels and premature cardiovascular disease. OBJECTIVE: In this study, we evaluated the clinical phenotype of the p.Asp47Asn, described as an uncertain pathogenic variant, and its effect on the structure of LDL-R and ligand interactions with apolipoproteins. METHODS: 27 children and adolescents with suspected FH diagnosis were recruited from a pediatric endocrinology outpatient clinic. Blood samples were collected after 12 h fasting for lipid profile analysis. DNA sequencing was performed for six FH-related genes by Ion Torrent PGM platform and copy number variation by MLPA. For index cases, a familial cascade screening was done restricted to the same mutation found in the index case. In silico analysis were developed to evaluate the binding capacity of LDL-R to apolipoproteins B100 and E. RESULTS: Lipid profile in children and adolescents demonstrated higher LDL-C levels in p.Asp47Asn carriers compared to the wild type genotype. In silico analysis predicted a reduction in the binding capacity of the ligand-binding modules LA1-2 of p.Asp47Asn LDL-R for ApoB100 and ApoE, which was not produced by local structural changes or folding defects but as a consequence of a decreased apparent affinity for both apolipoproteins. CONCLUSION: The clinical phenotype and the structural effects of p.Asp47Asn LDL-R mutation suggest that this variant associates to FH.

Ultrastructural changes in methicillin-resistant Staphylococcus aureus (MRSA) induced by a novel cyclic peptide ASP-1 from Bacillus subtilis: A scanning electron microscopy (SEM) study.

Increasing antimicrobial resistance among Staphylococcus aureus necessitates a new antimicrobial with a different site of action. We have isolated a novel cyclic peptide-1 (ASP-1) from Bacillussubtilis with potent activity against methicillin-resistant S. aureus (MRSA) at a minimum inhibitory concentration (MIC) of 8-64µg/ml. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of ASP-1 treated cells of S. aureus ATCC 29213 and an MRSA clinical isolate at MICs, with damages to the cell wall, membrane lysis and probable leakage of cytoplasmic contents at minimum bactericidal concentrations. The ultrastructure alterations induced by ASP-1 have also been compared with those of oxacillin-treated MRSA cells at its MIC using scanning electron microscopy.

Small interfering RNA for cancer treatment: overcoming hurdles in delivery.

In many ways, cancer cells are different from healthy cells. A lot of tactical nano-based drug delivery systems are based on the difference between cancer and healthy cells. Currently, nanotechnology-based delivery systems are the most promising tool to deliver DNA-based products to cancer cells. This review aims to highlight the latest development in the lipids and polymeric nanocarrier for siRNA delivery to the cancer cells. It also provides the necessary information about siRNA development and its mechanism of action. Overall, this review gives us a clear picture of lipid and polymer-based drug delivery systems, which in the future could form the base to translate the basic siRNA biology into siRNA-based cancer therapies.

Rapid Domoic Acid Depuration in the Scallop Argopecten purpuratus and Its Transfer from the Digestive Gland to Other Organs.

Domoic acid (DA), the main toxin responsible for Amnesic Shellfish Poisoning, frequently affects the marine resources of Chile and other countries across the South Pacific, thus becoming a risk for human health. One of the affected resources is the scallop Argopecten purpuratus. Even though this species has a high commercial importance in Northern Chile and Peru, the characteristics of its DA depuration are not known. In this work, the DA depuration was studied by means of two experiments: one in controlled (laboratory) and another in natural conditions. All organs of A. purpuratus depurated the toxin very quickly in both experiments. In some organs, an increase or a very small decrease of toxin was detected in the early depuration steps. Several models were used to describe this kinetics. The one that included toxin transfer between organs and independent depuration from each organ was the model that best fit the data. It seems, therefore, that the DA in this species is quickly transferred from the digestive gland to all other organs, which release it into the environment. Physiological differences in the two experiments have been shown to have some effect on the depuration from each organ but the actual reasons are still unknown.

LDLR Gene Mutation p.Asp360His and Familial Hypercholesterolemia in a Mexican Community.

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant disease characterized by an increased LDL-cholesterol (LDLc) serum concentration and premature cardiovascular disease. Screening of small populations where at least one homozygous (HoFH) patient has been identified may be a proper approach for detecting FH patients. Previously, we reported an HoFH patient carrying the mutation p.Asp360His LDLR, who was born in the Mexican community El Triunfo (Quimixtlan, Puebla). AIM OF THE STUDY: To identify patients with familial hypercholesterolemia in the community El Triunfo and to describe their clinical and biochemical characteristics. METHODS: We studied 308 individuals by quantifying lipid levels and by DNA sequencing. RESULTS: Sixteen of 308 individuals presented an LDLc level >170 mg/dL and all of them turned out to be heterozygous for the LDLR p.Asp360His variant. Subsequently, 34 of their first-degree relatives (mainly siblings and parents) were genotyped rendering six additional HeFH patients, which resulted in 22 carriers of the mutated allele. The study of six LDLR polymorphisms in four unrelated individuals from the community (one HoFH and three HeFH) showed the same haplotype combination, suggesting a unique ancestral origin of the mutation. CONCLUSIONS: The community El Triunfo, has the highest worldwide frequency ever reported of HeFH, with 7.14% (22/308, equivalent to 1/14 inhabitants). Since the HeFH patients showed variable biochemical expression, we suggest looking for factors with the potential to modify the phenotype. Finally, we stress the importance of establishing accurate LDLc cut-off points applicable to Mexican population for the diagnosis of FH.

Risk Factors for Unnecessary Antibiotic Prescribing for Acute Respiratory Tract Infections in Primary Care.

OBJECTIVE: To determine independent risk factors for inappropriate antibiotic prescribing for acute respiratory tract infections (ARIs) in internal medicine (IM) residency-based primary care offices. PATIENTS AND METHODS: A retrospective study was conducted to measure antibiotic prescribing rates, and multivariable analysis was utilized to identify predictors of inappropriate prescribing among patients presenting to IM residency-based primary care office practices. Patients with an office visit at either of 2 IM residency-based primary care office practices from January 1, 2016, through December 31, 2016, with a primary encounter diagnosis of ARI were included. RESULTS: During the study period, 911 unique patient encounters were included with 518 for conditions for which antibiotics were considered always inappropriate. Antibiotics were not indicated in 85.8% (782 of 911) of encounters. However, antibiotics were prescribed in 28.4% (222 of 782) of these encounters. Inappropriate antibiotic prescribing occurred in 111 of 518 (21.4%) encounters for conditions for which antibiotics are always inappropriate. Using multivariable logistic regression analysis to assess for independent risk factors when adjusted for other potential risk factors for office visits at which antibiotics were not indicated, IM resident-associated visits (odds ratio, 0.25; 95% CI, 0.18-0.36) was the only variable independently associated with lower risk of inappropriate antibiotic prescribing. CONCLUSION: For ARI visits at which antibiotics were not indicated, IM resident comanagement was associated with lower rates of inappropriate prescribing.

Impact of Procalcitonin Levels Combined with Active Intervention on Antimicrobial Stewardship in a Community Hospital.

BACKGROUND: Procalcitonin (PCT) guidance alone or in conjunction with antibiotic stewardship programs (ASP) has been shown to reduce antibiotic utilization and duration of therapy without adversely affecting patient outcomes. METHODS: In a community hospital, we investigated the impact of PCT with ASP recommendations on length of stay (LOS), length of antimicrobial therapy (LOT) after ASP recommendation, and total LOT over a one-year period. Adult patients with at least one PCT value and concomitant ASP recommendations were included. Patients were grouped by provider ASP compliance and further stratified by normal versus elevated PCT values. No specific PCT algorithm was utilized. RESULTS: A total of 857 patients were retrospectively analyzed. Physicians complied with 73.7% of ASP recommendations. There were no significant differences in LOS based on ASP compliance. Mean LOT after ASP recommendations and mean total LOT were significantly shorter (2.5 vs. 3.9 days, p<0.0001 and 5.1 vs. 6.6 days, p<0.0001, respectively) in the ASP complier group. When stratified by initial PCT levels, ASP compliers for patients with normal PCT levels had the shortest duration of therapy for all groups; among patients with elevated PCT levels, the duration of therapy was significantly shorter in the ASP compliant group (5.79 vs. 7.12 days, p<0.0111). When controlling for baseline differences in initial PCT levels, LOS was found to be marginally shorter in the ASP compliant group (p = 0.076). CONCLUSIONS: PCT-guided ASP physician recommendations, when accepted by providers, led to reduction in antimicrobial LOT in a community hospital. This benefit was extended across patient groups irrespective of initial PCT levels.

Structure and ligand binding of As-p18, an extracellular fatty acid binding protein from the eggs of a parasitic nematode.

Intracellular lipid-binding proteins (iLBPs) of the fatty acid-binding protein (FABP) family of animals transport, mainly fatty acids or retinoids, are confined to the cytosol and have highly similar 3D structures. In contrast, nematodes possess fatty acid-binding proteins (nemFABPs) that are secreted into the perivitelline fluid surrounding their developing embryos. We report structures of As-p18, a nemFABP of the large intestinal roundworm Ascaris suum, with ligand bound, determined using X-ray crystallography and nuclear magnetic resonance spectroscopy. In common with other FABPs, As-p18 comprises a ten ß-strand barrel capped by two short α-helices, with the carboxylate head group of oleate tethered in the interior of the protein. However, As-p18 exhibits two distinctive longer loops amongst ß-strands not previously seen in a FABP. One of these is adjacent to the presumed ligand entry portal, so it may help to target the protein for efficient loading or unloading of ligand. The second, larger loop is at the opposite end of the molecule and has no equivalent in any iLBP structure yet determined. As-p18 preferentially binds a single 18-carbon fatty acid ligand in its central cavity but in an orientation that differs from iLBPs. The unusual structural features of nemFABPs may relate to resourcing of developing embryos of nematodes.

Therapeutical effects of vaccine from Trypanosoma cruzi amastigote surface protein 2 by simultaneous inoculation with live parasites.

The aim of this study was to evaluate the efficacy of vaccine using replication-deficient human recombinant Type 5 replication-defective adenoviruses (AdHu5) carrying sequences of the amastigote surface protein 2 (ASP2) (AdASP2) in mice infected with the Trypanosoma cruzi ( T cruzi) Y strain. A total of 16 A/Sn mice female were distributed into four groups, as follows (n = 4 per group): Group 1 - Control Group (CTRL); Group 2 - Infected Group (TC): animals were infected by subcutaneous route with 150 bloodstream trypomastigotes of T cruzi Y strain; Group 3 - Immunized Group (AdASP-2): animals were immunized by intramuscular injection (im) route with 50 µL of AdSP-2 (2 × 10 8 plaque forming units [pfu]/cam) at day 0; Group 4-Immunized and Infected Group (AdASP-2+TC): animals were immunized by im route with 50 µL of ASP-2 (2 × 10 8 pfu/cam) and infected by T cruzi at the same day (day 0). It was observed a significant decrease of nests in the group that was immunized with AdASP-2 and infected on the same day. Tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthase (iNOS) gene expressions showed a significant increase in the AdASP-2+TC group when compared to TC group, but it was noted that Cyclooxygenase-2 (Cox-2) was increased in TC group when compared to AdASP-2+TC group. Increase of matrix metalloproteinases-2 (MMP-2) and decrease of MMP-9 immunoexpression in the AdASP-2+TC group was noticed as well. Oxidative DNA damage was present in myocardium for AdASP-2+TC group as a result of 8-hydroxydeoxyguanosine immunoexpression. Taken together, our results highlighted an increased oxidative stress, MMP-2 activity and inflammatory host response promoted by AdASP-2 against T cruzi infection.

Defining Substrate Specificity in the CTX-M Family: the Role of Asp240 in Ceftazidime Hydrolysis.

The natural diversification of CTX-M ß-lactamases led to the emergence of Asp240Gly variants in the clinic that confer reduced susceptibility to ceftazidime (CAZ). In this study, we compared the impact of this substitution on CAZ and ceftazidime-avibactam (CZA) MICs against isogenic Escherichia coli strains with different porin deficiencies. Our results show a noticeable increase in CAZ resistance in clones expressing Asp240Gly-harboring CTX-M when combined with OmpF porin deficiency. Kinetic analysis revealed that the kcat/Km for CAZ was 5- to 15-fold higher for all Asp240Gly variants but remained 200- to 725-fold lower than that for cefotaxime (CTX). In vitro selection of CAZ-resistant clones yielded nonsusceptible CTX-M producers (MIC of >16 µg/ml) only after overnight incubation; the addition of avibactam (AVI) decreased MICs to a susceptible range against these variants. In contrast, the use of CZA as a selective agent did not yield resistant clones. AVI inactivated both CTX-M-12 and CTX-M-96, with an apparent inhibition constant comparable to that of SHV-2 and 1,000-fold greater than that of PER-2 and CMY-2, and k2/K for CTX-M-12 was 24- and 35-fold higher than that for CTX-M-96 and CTX-M-15, respectively. Molecular modeling suggests that AVI interacts similarly with CTX-M-96 and CTX-M-15. We conclude that the impact of Asp240Gly in resistance may arise when other mechanisms are also present (i.e., OmpF deficiency). Additionally, CAZ selection could favor the emergence of CAZ-resistant subpopulations. These results define the role of Asp240 and the impact of the -Gly substitution and allow us to hypothesize that the use of CZA is an effective preventive strategy to delay the development of resistance in this family of extended-spectrum ß-lactamases.

ASP49-phospholipase A2-loaded liposomes as experimental therapy in cutaneous leishmaniasis model.

This study aimed to evaluate the in vivo anti-Leishmania amazonensis activity of a Phospholipase A2 (Asp49-PLA2), isolated from Bothrops jararacussu venom, encapsulated in liposomes as a modified toxin release system. The activity of the liposomes was evaluated in BALB/c mice, previously infected with 1×105 of the parasite's promastigotes. The size of the paw lesion in Asp49-PLA2-liposomal-treated animals, after 21days, was observed as decreasing by 16% relative to the untreated control group and 12% by the Glucantime®-treated animals, which was used as a reference drug. At the end of the treatment, the animals were sacrificed and the paw and lymph node tissues were collected. Part of the collection was used to recover amastigotes and another to quantify cytokines and nitrites. In the group treated with Asp49-PLA2-liposomes the parasitic load was observed to be reduced by 73.5% in the macerated lymph node, compared to the control group. Comparatively, in the paw tissue was observed a reduction of 57.1%. The infected groups treated with Asp49-PLA2-liposomes showed significant production in TNF-α measured in lymph nodes and paw (43.73pg/mL±2.25 and 81.03pg/mL±5.52, respectively) and nitrite levels (31.28µM±0.58 and 35.64µM±5.08) also measured in lymph nodes and paw tissues, respectively, compared to untreated groups. These results indicate that the Asp49-PLA2-loaded liposomes were able to activate the production of some cellular components of the protective TH1 response during the infection, constituting a promising tool for inducing the microbicidal activity of the Leishmania-infected macrophages.

Vanadium: History, chemistry, interactions with α-amino acids and potential therapeutic applications.

In the last 30 years, since the discovery that vanadium is a cofactor found in certain enzymes of tunicates and possibly in mammals, different vanadium-based drugs have been developed targeting to treat different pathologies. So far, the in vitro studies of the insulin mimetic, antitumor and antiparasitic activity of certain compounds of vanadium have resulted in a great boom of its inorganic and bioinorganic chemistry. Chemical speciation studies of vanadium with amino acids under controlled conditions or, even in blood plasma, are essential for the understanding of the biotransformation of e.g. vanadium antidiabetic complexes at the physiological level, providing clues of their mechanism of action. The present article carries out a bibliographical research emphaticizing the chemical speciation of the vanadium with different amino acids and reviewing also some other important aspects such as its chemistry and therapeutical applications of several vanadium complexes.

Relationship between the Asp1104His polymorphism of the nucleotide excision repair gene ERCC5 and treatment sensitivity to oxaliplatin in patients with advanced colorectal cancer in China

OBJECTIVES: To study the relationship between the Asp1104His polymorphism of the nucleotide excision repair gene ERCC5 and treatment sensitivity to oxaliplatin in patients with advanced colorectal cancer (CRC) in China. METHODS: A group of 226 patients in the Department of Gastrointestinal Oncology at Zhejiang Xiaoshan Hospital from July 2011∼December 2016 and a control group of 226 normal healthy individuals were involved in this study. All patients were first diagnosed with advanced CRC and were treated with oxaliplatin-based chemotherapy. The genotype of ERCC5 at the site of amino acid 1104 was determined by a TaqMan probe-based real-time PCR approach. RESULTS: There were no differences in age or gender between the groups, but the percentages of smokers and individuals with a family history of cancer were significantly higher in the patient group than in the control group. Analysis of the G/C polymorphism frequency among the patients and the healthy controls showed that the frequencies of the CC genotype and the CC+GC genotype were significantly related to CRC, but no significant difference in these frequencies was found between genders. The analysis of the relationship between the 5-year survival rate and different genotypes showed that in the total patient group, regardless of gender, the 5-year survival rate was significantly associated with the Asp1104His polymorphism of ERCC5. CONCLUSIONS: The Asp1104His polymorphism of ERCC5 was associated with the risk and 5-year survival rate of CRC as well as treatment sensitivity to oxaliplatin.