Growth-Mindset Intervention Delivered by Teachers Boosts Achievement in Early Adolescence.

School underachievement is a persistent problem in the United States. Direct-to-student, computer-delivered growth-mindset interventions have shown promise as a way to improve achievement for students at risk of failing in school; however, these interventions benefit only students who happen to be in classrooms that support growth-mindset beliefs. Here, we tested a teacher-delivered growth-mindset intervention for U.S. adolescents in Grades 6 and 7 that was designed to both impart growth-mindset beliefs and create a supportive classroom environment where those beliefs could flourish (N = 1,996 students, N = 50 teachers). The intervention improved the grades of struggling students in the target class by 0.27 standard deviations, or 2.81 grade percentage points. The effects were largest for students whose teachers endorsed fixed mindsets before the intervention. This large-scale, randomized controlled trial demonstrates that growth-mindset interventions can produce gains when delivered by teachers.

In vitro biological activity of extracts from marine bacteria cultures against Toxoplasma gondii and Mycobacterium tuberculosis.

AIMS: To evaluate the biological activity of extracts from cultures of marine bacteria against Toxoplasma gondii and Mycobacterium tuberculosis. METHODS AND RESULTS: Ethyl acetate extracts obtained from seven marine bacteria were tested against T. gondii GFP-RH and M. tuberculosis H37Rv. The cytotoxicity on HFF-1 cells was measured by a microplate resazurin fluorescent approach, and the haemolytic activity was determined photometrically. The extracts from Bacillus sp. (INV FIR35 and INV FIR48) affected the tachyzoite viability. The extracts from Bacillus, Pseudoalteromonas, Streptomyces and Micromonospora exhibited effects on infection and proliferation processes of parasite. Bacillus sp. INV FIR48 extract showed an minimum inhibitory concentration value of 50 µg ml-1 against M. tuberculosis H37Rv. All the extracts exhibited relatively low toxicity to HFF-1 cells and the primary culture of erythrocytes, except Bacillus sp. INV FIR35, which decreased cell viability under 20%. Liquid chromatography coupled to mass spectrometry analysis of the most active bacterial extract Bacillus sp. INV FIR48 showed the presence of peptide metabolites related to surfactin. CONCLUSIONS: The extract from culture of deep-sea Bacillus sp. INV FIR48 showed anti-T. gondii and anti-tuberculosis (TB) biological activity with low cytotoxicity. In addition, peptide metabolites were detected in the extract. SIGNIFICANCE AND IMPACT OF THE STUDY: Toxoplasmosis and TB are among the most prevalent diseases worldwide, and the current treatment drugs exhibit side effects. This study confirm that marine bacteria are on hand sources of anti-infective natural products.

Naringin reduces body weight, plasma lipids and increases adiponectin levels in patients with dyslipidemia.

Naringin is a citrus-flavonoid which has been shown to have positive metabolic and anti-inflammatory effects. For this reason, we believe it would be interesting to study the effects of Naringin administration on body weight, BMI, lipid profile and adiponectin levels in patients with dyslipidemia, especially considering that dyslipidemias along with obesity and subsequent cardiometabolic complications are some of the most important public health issues plaguing our society today. A double-blind, randomized clinical trial was conducted in a group of 28 adult patients previously diagnosed with dyslipidemia who attended the Institute of Experimental and Clinical Therapeutics. Patients were divided into two groups; the first group (n = 14) received 450 mg of naringin every 24 hours, in the mornings, while the second group (n = 14) was given a homologated placebo over the course of a 90-day period. Significant differences were observed in naringin group compared to the placebo group in terms of decreased BMI (30.6 ± 3.19 vs 33.3 ± 3.23 kg/m2; p = 0.03), total cholesterol (182 ± 20.2 vs 245 ± 24.1 mg/dl; p < 0.01), LDL cholesterol (100 ± 17.5 vs 125 ± 38.3 mg/dl; p = 0.03) and an increase in adiponectin levels (0.82 ± 0.25 vs 0.59 ± 0.19 µg/ml; p = 0.01). Our results support the use of Naringin as a potential therapeutic agent which could play an important role in the management of metabolic disorders.

Protein targets of thiazolidinone derivatives in Toxoplasma gondii and insights into their binding to ROP18.

BACKGROUND: Thiazolidinone derivatives show inhibitory activity (IC50) against the Toxoplasma gondii parasite, as well as high selectivity with high therapeutic index. To disclose the target proteins of the thiazolidinone core in this parasite, we explored in silico the active sites of different T. gondii proteins and estimated the binding-free energy of reported thiazolidinone molecules with inhibitory effect on invasion and replication of the parasite inside host cells. This enabled us to describe some of the most suitable structural characteristics to design a compound derived from the thiazolidinone core. RESULTS: The best binding affinity was observed in the active site of kinase proteins, we selected the active site of the T. gondii ROP18 kinase, because it is an important factor for the virulence and survival of the parasite. We present the possible effect of a derivative of thiazolidinone core in the active site of T. gondii ROP18 and described some characteristics of substituent groups that could improve the affinity and specificity of compounds derived from the thiazolidinone core against T. gondii. CONCLUSIONS: The results of our study suggest that compounds derived from the thiazolidinone core have a preference for protein kinases of T. gondii, being promising compounds for the development of new drugs with potential anti-toxoplasmosis activity. Our findings highlight the importance of use computational studies for the understanding of the action mechanism of compounds with biological activity.

Role of the 52 KDa thioredoxin protein disulfide isomerase of Toxoplasma gondii during infection to human cells.

Toxoplasma protein disulfide isomerase (PDI) is a 52 KDa thioredoxin of interest because have a great immunogenicity for humans. We cloned and produced a recombinant protein (recTgPDI) used to test its effect during infection to different human cell lines (epithelial and retinal). We also determine if there were differences in gen expression during in vitro infection. Expression of the gen was lower after entry into the host cells. PDI's inhibitors bacitracin and nitroblue tetrazolium reduced the percent of infected cells and small amounts of recTgPDI proteins interfered with the invasion step. All these results support a role of Toxoplasma PDI during the first steps of infection (adhesion and invasion). Toxoplasma PDI is a protein linked to early steps of invasion, it would be of importance to identify the host proteins substrates during invasion steps.

Nutrient leaching in a Colombian savanna Oxisol amended with biochar.

Nutrient leaching in highly weathered tropical soils often poses a challenge for crop production. We investigated the effects of applying 20 t ha biochar (BC) to a Colombian savanna Oxisol on soil hydrology and nutrient leaching in field experiments. Measurements were made over the third and fourth years after a single BC application. Nutrient contents in the soil solution were measured under one maize and one soybean crop each year that were routinely fertilized with mineral fertilizers. Leaching by unsaturated water flux was calculated using soil solution sampled with suction cup lysimeters and water flux estimates generated by the model HYDRUS 1-D. No significant difference ( > 0.05) was observed in surface-saturated hydraulic conductivity or soil water retention curves, resulting in no relevant changes in water percolation after BC additions in the studied soils. However, due to differences in soil solution concentrations, leaching of inorganic N, Ca, Mg, and K measured up to a depth of 0.6 m increased ( < 0.05), whereas P leaching decreased, and leaching of all nutrients (except P) at a depth of 1.2 m was significantly reduced with BC application. Changes in leaching at 2.0 m depth with BC additions were about one order of magnitude lower than at other depths, except for P. Biochar applications increased soil solution concentrations and downward movement of nutrients in the root zone and decreased leaching of Ca, Mg, and Sr at 1.2 m, possibly by a combination of retention and crop nutrient uptake.

Residues of veterinary drugs and heavy metals in bovine meat from Urabá (Antioquia, Colombia), a promising step forward towards international commercialization.

Veterinary drugs are used for disease control in bovines Their presence at acceptable levels is a cause of concern for consumers and control agencies, as well as being a limitation for accessing international markets. The objective of this research was to evaluate the presence of residues of veterinary drugs and heavy metals in meat cuts from the Urabá region in Colombia. From a total of 80 samples of meat cuts from the loin and neck, we determined the presence of 29 veterinary drug residues and of cadmium and lead. The drug residues were quantified by liquid chromatography coupled to mass spectrometry. Heavy metals were measured by electrothermal atomic absorption. As a result, all evaluated samples complied with Colombian and European regulations for drug residues and heavy metals. These results demonstrate good veterinary practices used for bovines raised in this part of Colombia, and they represent an export opportunity and an opening for new markets that can be enhanced by the implementation of a meat quality seal from this region.

In vitro evaluation of new 4-thiazolidinones on invasion and growth of Toxoplasma gondii.

Treatments for toxoplasmosis such as pyrimethamine have shown numerous side effects. It has been reported that the likelihood of relapse associated with pyrimethamine-based therapy in patients with HIV and toxoplasmic encephalitis (TE) can have significant implications, even for patients who often develop new lesions in areas of the brain previously free of infection. This led us to research for new agents against Toxoplasma gondii. Recent findings have shown the potent biological activity of 4-thiazolidinones. We proposed to design and synthesize a new series of 2-hydrazono-4-thiazolidinones derivatives to evaluate the in vitro growth inhibition effect on T. gondii. The growth rates of T. gondii tachyzoites in Human Foreskin Fibroblast (HFF) cell culture were identified by two in vitro methodologies. The first one was by fluorescence in which green fluorescent RH parasites and cherry-red fluorescent ME49 parasites were used. The second one was a colorimetric methodology using ß-Gal parasites of the RH strain constitutively expressing the enzyme beta-galactosidase. The 4-thiazolidinone derivatives 1B, 2B and 3B showed growth inhibition at the same level of Pyrimethamine. These compounds showed IC50 values of 1B (0.468-0.952 µM), 2B (0.204-0.349 µM) and 3B (0.661-1.015 µM) against T. gondii. As a measure of cytotoxicity the compounds showed a TD50 values of: 1B (60 µM), 2B (206 µM) and 3B (125 µM). The in vitro assays and molecular modeling results suggest that these compounds could act as possible inhibitors of the Calcium-Dependent Protein Kinase 1 of T. gondii. Further, our results support the fact that of combining appropriate detection technologies, combinatorial chemistry and computational biology is a good strategy for efficient drug discovery. These compounds merit in vivo analysis for anti-parasitic drug detection.

Offseason Medfly Trapping Using Makeshift Fruit-Based and Wine Vinegar Baits.

Development of cost-effective traps and attractants is important for sustainable pest management. In the case of the Medfly, Ceratitis capitata Wiedemann, a worldwide pest of fruit production, recent interest in development of mass trapping strategies and low-cost easy-to-get artisanal traps for resource poor grower use has prompted renewed interest in research on attractants and traps. Additionally, such interest is also rooted on the need for effective female attractants to monitor wild population dynamics under male-only sterile fly releases. Response of wild flies and sterile males to makeshift traps (modified polyethylene terephthalate (pet) bottles) baited with fruit juice and wine vinegar dilutions with and without the addition of sugar revealed that a 50% dilution of wine vinegar or sweetened orange juice were more attractive than the standard Torula baits during the offseason (after harvest) in a peach orchard in arid irrigated valleys of San Juan Argentina. Such results suggest that volatiles from orange peel and juice are good candidates for development of Medfly attractants, and that pet bottles baited with sweetened orange juice and wine vinegar may be used by small growers and homeowners as low-cost-effective traps for Medfly control. Our results also suggest that Medfly response to food-based and fruit-based volatiles may be seasonally dynamic, a finding with important pest management implications.

Effect of pretreatment and temperature on the drying kinetics and physicochemical and techno-functional characteristics of pumpkin (Cucurbita maxima).

The study was carried out to assess fresh slices and thermally pretreated pumpkin (Cucurbita maxima) dried at temperatures of 55 °C, 60 °C, 65 °C, and 70 °C. The drying kinetics and quality attributes of the dried product were determined, and results indicated that the modified Page model was the best fit, with activation energies of 29.47 kJ mol-1 and 16.06 kJ mol-1 for drying fresh and thermally pretreated slices, respectively. A significant effect (p < 0.05) related to thermal pretreatment and temperature was evidenced on the physicochemical properties. The fresh pulp powders presented the following ranges of moisture and color (ΔE), 7.10%-8.31% w.b.; 21.23-25.23, respectively, and for the pretreated pulp powders, they were 8.94%-11.54% w.b., and from 19.00- 28.30, respectively. There were no significant effects on the techno-functional properties in the powders; cold water solubility was 5.36%-6.46%, water absorption capacity was 3.42-6.52 g/g, and oil absorption capacity was 1.00-1.30 g/g. The carbohydrate and fiber contents significantly decreased in the pretreated powder. An increase in antioxidant activity was found in fresh and thermally pretreated pulp powder at a temperature of 70 °C, presenting values between 2.23-2.98 µmol Trolox equivalent g-1d.b. evaluated by the DPPH method and between 40.48-45.92 µmol Trolox equivalent g-1d.b. by ABTS, and no significant differences (p > 0.05) were determined after pulp pretreatment. The total content of carotenoids presented retention percentages for fresh pulp powders of 52.09%, 41.92%, 30.55%, and 22.79%, while for pretreated pulp powders, they were 30.67%, 32.86%, 24.84%, and 14.71% when dried at temperatures of 55 °C, 60 °C, 65 °C, and 70 °C, respectively. The powders obtained from heat-pretreated pumpkin pulp showed significant differences (p < 0.05) in physicochemical characteristics and total carotenoids, but they were not found (p > 0.05) in the techno-functional properties and antioxidant activity evaluated by the DPPH and ABTS methods.

Radiation on Medfly Larvae of tsl Vienna-8 Genetic Sexing Strain Displays Reduced Parasitoid Encapsulation in Mass-Reared Diachasmimorpha longicaudata (Hymenoptera: Braconidae).

Improvements in the mass rearing of Diachasmimorpha longicaudata (Ashmead) on larvae of the Vienna-8 temperature-sensitive lethal genetic sexing strain of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) (= GSS Vienna-8) at the San Juan biofactory, Argentina, are currently under way. Lowering cost production is a key factor regarding parasitoid rearing. Thus, the variation in mass-reared parasitoid encapsulation levels and the incidence of superparasitism were determined; also, the gamma radiation dose-effect relation on host larvae and the influence of Mediterranean fruit fly strain were considered. Naked Mediterranean fruit fly larvae of both GSS Vienna-8 and a wild bisexual strain (= WBS) aged 6-d-old were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, and exposed to parasitoid females. Melanization level was tested for encapsulated parasitoid larval first-instars (= L1). Non-irradiated and irradiated WBS larvae at 20-40 Gy displayed a significantly higher incidence of encapsulation when compared with GSS Vienna-8 larvae. The low melanized level in encapsulated parasitoid L1 was the most common melanization process at 72 h puparium dissection. A high melanized level was only found in non-irradiated WBS larvae. Irradiated GSS Vienna-8 larvae can neutralize the host immunological reactions over irradiated WBS larvae much more quickly. Superparasitism intensity in both Mediterranean fruit fly strains was not affected by radiation doses. High levels of superparasitism seemingly helped to overcome the host's immune reaction by the surviving parasitoid larva. Parasitoid emergence increased from 60 Gy onwards in both Mediterranean fruit fly strains. Radiation in GSS Vienna-8 larvae may favor host's antagonistic reactions decrease in relation with D. longicaudata development.

Gait-cycle segmentation method based on lower-trunk acceleration signals and dynamic time warping.

Gait analysis is the systematic study of human walking. The analysis of gait signals from the lower trunk, acquired through accelerometers, begins with the proper identification of gait cycles. The goal of this work is to supplement gait-event based segmentation methods, tested for unimpaired and impaired populations, so that their need to calibrate or rely on pre-defined thresholds is overcome, and to implement strategies that reduce step-detection errors. A new system for the automatic extraction and analysis of gait cycles from acceleration signals of the lower trunk, combining knowledge from previous strategies with a dynamic time warping function, is presented. Performance was tested on gait signals from public databases. Sensitivities in step detection above 99.95% were achieved, with a positive predictive value of 100.00%. Step-correction strategies reduced the number of incorrect detections from 57 to 3 of 7056 steps. Bland-Altman plots and equivalence tests performed on cycle times by the proposed method and selected references showed good agreement, with mean differences below 0.003 s, and percent errors of 2%. This method may give place to a research tool for the automatic analysis of signals from subjects in a variety of cases.

Host Suitability and Fitness-Related Parameters in Coptera haywardi (Hymenoptera: Diapriidae) Reared on Irradiated Ceratitis capitata (Diptera: Tephritidae) Pupae Stemming From the tsl Vienna-8 Genetic Sexing Strain.

Coptera haywardi (Ogloblin) is a pupal endoparasitoid of tephritid flies with great potential as a biological control agent worldwide as it does not attack other Diptera. To reach its full potential, its mass rearing needs to be enhanced lowering costs. Here, we focused on the use of irradiated pupae of Ceratitis capitata (Wiedemann) stemming from the temperature-sensitive lethal (tsl) Vienna-8 genetic sexing strain (= CcVienna-8), which is mass-produced in the San Juan Medfly and Parasitoid Mass Rearing Facility in Argentina. Exposure of 1- to 2-d-old CcVienna-8 pupae irradiated at 90 Gy to 6- to 8-d-old C. haywardi females at a 10:1 host/parasitoid ratio for 24 h turned out to be highly successful for the rearing of this parasitoid. High radiation doses (90-100 Gy) did not adversely influence fitness parameters of C. haywardi offspring F1, namely lifetime reproductive rates, adult life expectancy, and survival time. Demographic parameters in C. haywardi F1 from irradiated CcVienna-8 young pupae were improved compared to those values recorded from parasitoid originated from nonirradiated CcVienna-8 pupae. These findings will help to enhance parasitoid mass rearing for augmentative releases against medfly in Argentinean fruit-producing regions.

Milk enriched with "healthy fatty acids" improves cardiovascular risk markers and nutritional status in human volunteers.

OBJECTIVE: The main goal of the present study was to evaluate the effect of a commercially available milk containing small amounts of eicosapentaenoic acid and docosahexaenoic acid, oleic acid, and vitamins A, B6, D, E, and folic acid compared with semi-skimmed and skimmed milk in volunteers with moderate cardiovascular risk. METHODS: Two hundred ninety-seven subjects 25 to 65 y of age with moderate cardiovascular risk were randomly allocated into three groups. In addition to their diets, one group consumed 500 mL/d of the enriched milk, another group consumed 500 mL/d of skimmed milk, and a control group consumed 500 mL/d of semi-skimmed milk. All groups consumed the dairy drinks for 1 y and blood samples were taken at 0 and 12 mo. RESULTS: Consumption of enriched milk for 1 y produced significant (P < 0.05) increases in serum folate (58%) and high-density lipoprotein cholesterol (4%). Plasma triacylglycerols (10%), total cholesterol (4%), and low-density lipoprotein cholesterol (6%) were reduced significantly only in the supplemented group. Serum glucose, homocysteine, and C-reactive protein remained unchanged. In the skimmed milk and semi-skimmed milk groups, the only significant decreases were in serum folate (17% and 11%, respectively). CONCLUSION: Daily intake of a milk enriched with fish oil, oleic acid, and vitamins improved the nutritional status and cardiovascular risk markers of volunteers, whereas skimmed milk and semi-skimmed milk did not.

Enzyme-Linked Aptamer Assay (ELAA) for Detection of Toxoplasma ROP18 Protein in Human Serum.

Toxoplasma gondii engenders the common parasitic disease toxoplasmosis in almost all warm-blooded animals. Being a critical secretory protein, ROP18 is a major virulence factor of Toxoplasma. There are no reports about ROP18 detection in human serum samples with different clinical manifestations. New aptamers against ROP18 protein were developed through Systematic Evolution of Ligands by Exponential enrichment (SELEX). An Enzyme-Linked Aptamer Assay (ELAA) platform was developed using SELEX-derived aptamers, namely AP001 and AP002. The ELAA was used to evaluate total antigen from T. gondii RH strain (RH Ag) and recombinant protein of ROP18 (rROP18). The results showed that the ELAA presented higher affinity and specificity to RH Ag and rROP18, compared to negative controls. Detection limit of rROP18 protein in serum samples was measured by standard addition method, achieving a lower concentration of 1.56 µg/mL. Moreover, 62 seropositive samples with different clinical manifestations of toxoplasmosis and 20 seronegative samples were tested. A significant association between ELAA test positive for human serum samples and severe congenital toxoplasmosis was found (p = 0.006). Development and testing of aptamers-based assays opens a window for low-cost and rapid tests looking for biomarkers and improves our understanding about the role of ROP18 protein on the pathogenesis of human toxoplasmosis.

Analysis of viroid replication.

Viroids, as a consequence of not encoding any protein, are extremely dependent on their hosts. Replication of these minimal genomes, composed exclusively by a circular RNA of 246-401 nt, occurs in the nucleus (family Pospiviroidae) or in the chloroplast (family Avsunviroidae) by an RNA-based rolling-circle mechanism with three steps: (1) synthesis of longer-than-unit strands catalyzed by host DNA-dependent RNA polymerases recruited and redirected to transcribe RNA templates, (2) cleavage to unit-length, which in family Avsunviroidae is mediated by hammerhead ribozymes, and (3) circularization through an RNA ligase or autocatalytically. This consistent but still fragmentary picture has emerged from a combination of studies with in vitro systems (analysis of RNA preparations from infected plants, transcription assays with nuclear and chloroplastic fractions, characterization of enzymes and ribozymes mediating cleavage and ligation of viroid strands, dissection of 5' terminal groups of viroid strands, and in situ hybridization and microscopy of subcellular fractions and tissues), and in vivo systems (tissue infiltration studies, protoplasts, studies in planta and use of transgenic plants expressing viroid RNAs).

A Perspective on Thiazolidinone Scaffold Development as a New Therapeutic Strategy for Toxoplasmosis.

Toxoplasma gondii is one of the most successful parasites due to its ability to infect a wide variety of warm-blooded animals. It is estimated that one-third of the world's population is latently infected. The generic therapy for toxoplasmosis has been a combination of antifolates such as pyrimethamine or trimethoprim with either sulfadiazine or antibiotics such as clindamycin with a combination with leucovorin to prevent hematologic toxicity. This therapy shows limitations such as drug intolerance, low bioavailability or drug resistance by the parasite. There is a need for the development of new molecules with the capacity to block any stage of the parasite's life cycle in humans or in a different type of hosts. Heterocyclic compounds are promissory drugs due to its reported biological activity; for this reason, thiazolidinone and its derivatives are presented as a new alternative not only for its inhibitory activity against the parasite but also for its high selectivity-level with high therapeutic index. Thiazolidinones are an important scaffold known to be associated with anticancer, antibacterial, antifungal, antiviral, antioxidant, and antidiabetic activities. The molecule possesses an imidazole ring that has been described as an antiprotozoal agent with antiparasitic properties and less toxicity. Thiazolidinone derivatives have been reportedly as building blocks in organic chemistry and as scaffolds for drug discovery. Here we present a perspective of how structural modifications of the thiazolidinone core could generate new compounds with high anti-parasitic effect and less toxic results.

In silico study of Moxifloxacin derivatives with possible antibacterial activity against a resistant form of DNA gyrase from Porphyromonas gingivalis.

We performed a homology modeling of the structure of a non-mutated and mutated Ser83→Phe DNA gyrase of Porphyromonas gingivalis. The model presented structural features conserved in type II topoisomerase proteins. We designed and evaluated in silico structural modifications to the core of Moxifloxacin by molecular docking, predicted toxicity and steered molecular dynamics simulations (SMD). Our results suggest that 8D derivative of Moxifloxacin could present a strong inhibitory activity in Porphyromonas gingivalis bacteria that exhibits resistance to some conventional fluoroquinolone drugs. Also, our results suggest that hydrophobic radicals in the hydroxyl group at position 3 of the quinolone core would increase the antibacterial activity of the compound when a reported mutation Ser83→Phe is present in the DNA gyrase protein. In addition, new candidates that could have a higher antibacterial activity compared to Moxifloxacin in non-resistant bacteria are proposed.