Efficacy of winter–spring strategic control against Rhipicephalus (Boophilus) microplus infestations on cattle in an area with ecological conditions highly favourable for the tick in northeast Argentina

This work was performed to test the efficacy of winter–spring control strategies against Rhipicephalus (Boophilus) microplus (Ixodida: Ixodidae) infestations on cattle in the area ecologically most favourable for the development of this tick in Argentina. Two control schemes using three and four annual applications of acaricides, respectively, were evaluated. Animals in Group 1 were treated with ivermectin 3.15% on day 0, fluazuron on day 34, and fipronil on day 85. Animals in Group 2 were treated with ivermectin 3.15% on day 0, fluazuron on day 34, flumethrin on day 85, and fipronil on day 114. Animals in Group 3 represented the control group. Both treatment schemes provided appropriate levels of efficacy against R. microplus and also prevented the occurrence of the major peak in the frequency of this tick in autumn. The two treatment schemes were similar in terms of efficacy and thus the addition of a fourth treatment does not seem to confer any further advantage. The results of this work indicate that these strategic control methods provide appropriate levels of control against R. microplus.     

Binding of hydrogen donors to horseradish peroxidase: A spectroscopic study

Absorption spectroscopy measurements of the binding of aromatic donors and competitive inhibitors to horseradish peroxidase indicate that they are bound to the enzyme through hydrophobic forces and hydrogen bonding. Nuclear magnetic resonance experiments show that the minimal distances between the enzyme iron and the protons of a typical donor, p-cresol, are 7.0 ± 0.5, 7.7 ± 0.5 and 8.5 ± 0.5 Å, for the ortho-, meta- and methyl-protons, respectively.A model for the binding of aromatic donors to horseradish peroxidase based on this result is presented. It is proposed that the aromatic ring is attached to a hydrophobic region in the protein interior and the phenol oxygen is hydrogen-bonded to the pyrrolic nitrogen of the iron-coordinated histidine. This structure is compatible with the proton-iron distances measured and offers an intramolecular path for electron conduction from donor to heme analogous to that proposed by Winfield for the peroxidases.     

An Optimized Method for Manufacturing a Clinical Scale Dendritic Cell-Based Vaccine for the Treatment of Glioblastoma

Immune-based treatments represent a promising new class of therapy designed to boost the immune system to specifically eradicate malignant cells. Immunotherapy may generate specific anti-tumor immune responses, and dendritic cells (DC), professional antigen-presenting cells, are widely used in experimental cancer immunotherapy. Several reports describe methods for the generation of mature, antigen-pulsed DC for clinical use. Improved quality and standardization are desirable to obtain GMP-compliant protocols. In this study we describe the generation of DC from 31 Glioblastoma (GB) patients starting from their monocytes isolated by immunomagnetic CD14 selection using the CliniMACS® device. Upon differentiation of CD14+ with IL-4 and GM-CSF, DC were induced to maturation with TNF-α, PGE₂, IL-1β, and IL-6. Whole tumor lysate was obtained, for the first time, in a closed system using the semi-automated dissociator GentleMACS®. The yield of proteins improved by 130% compared to the manual dissociation method. Interestingly the Mean Fluorescence Intensity for CD83 increased significantly in DC pulsed with “new method” lysate compared to DC pulsed with “classical method” lysate. Our results indicate that immunomagnetic isolation of CD14⁺ monocytes using the CliniMACS® device and their pulsing with whole tumor lysate proteins is a suitable method for clinical-scale generation of high quality, functional DC under GMP-grade conditions.     

Novel marine alkaloids from the tunicate Eudistoma sp. are potent regulators of cellular growth and differentiation and affect cAMP-mediated processes

Six novel alkaloids that contain a fused tetracyclic pyrido[2,3,4-kl]acridine ring system were purified recently from the Red Sea purple tunicate Eudistoma sp. Evaluation of the effects of these alkaloids on cultured neuroblastoma and fibroblast cells revealed that they possess potent growth regulatory properties, and affect cell shape and adhesion. In mouse neuroblastoma cells, the Eudistoma alkaloids inhibited cell proliferation and induced a process of differentiation during which the cels flattened onto the surface, increased considerably in size, and extended long neurites. In hamster fibroblasts the alkaloids slowed down cell multiplication, and caused an exceptional cell flattening or elongation. In a virustransformed derivative of the hamster fibroblasts the alkaloids restored many aspects of normal cell growth and morphology. In addition, several of the alkaloids mimicked the effects of cAMP analogs on two well-characterized cAMP-mediated processes involved in hepatic glucose metabolism–inhibition of pyruvate kinase (PK) activity and induction of mRNA for phosphoenolpyruvate carboxykinase (PEPCK). All these effects suggest that the Eudistoma alkaloids may act on the cAMP signaling system. However, a single application of these compounds was sufficient to completely block cell multiplication and to induce and sustain differentiation and “reverse transformation”. Furthermore, these effects were not readily reversible following removal of the drugs. In contrast, a single application of agents that mimic or elevate cAMP induced a transient response that waned with time in culture, and the effects induced by constant elevation of cAMP reverse rapidly following drug removal. We propose that the Eudistoma alkaloids cause growth inhibition, differentiation, and reverse transformation by modifying the activity state of proteins that are involved in the regulation of cell shape and adhesion and serve as a target for the cAMP and/or other second messenger systems. © 1993 Wiley-Liss, Inc.     

A Novel Approach to Recovery of Function of Mutant Proteins by Slowing Down Translation

Protein homeostasis depends on a balance of translation, folding, and degradation. Here, we demonstrate that mild inhibition of translation results in a dramatic and disproportional reduction in production of misfolded polypeptides in mammalian cells, suggesting an improved folding of newly synthesized proteins. Indeed, inhibition of translation elongation, which slightly attenuated levels of a copepod GFP mutant protein, significantly enhanced its function. In contrast, inhibition of translation initiation had minimal effects on copepod GFP folding. On the other hand, mild suppression of either translation elongation or initiation corrected folding defects of the disease-associated cystic fibrosis transmembrane conductance regulator mutant F508del. We propose that modulation of translation can be used as a novel approach to improve overall proteostasis in mammalian cells, as well as functions of disease-associated mutant proteins with folding deficiencies.     

Role of cardiovascular magnetic resonance in suspected cardiac amyloidosis: late gadolinium enhancement pattern as mortality predictor

Background

Cardiac magnetic resonance (CMR) has gained a central role in the diagnosis of cardiac amyloidosis (CA). While the diagnostic role of a typical late gadolinium enhancement (LGE) pattern (global subendocardial enhancement coupled with accelerated contrast washout) has been identified, evidence is still conflicting regarding the prognostic role of such examination.

Methods and results

We retrospectively analysed all patients referring for CMR at Niguarda Hospital (Milan, Italy) from January 2006 to January 2015 for suspected CA. Primary outcome was all-cause mortality. We identified 42 patients and divided them into 2 groups, according to the presence (Group A) or absence (Group B) of a typical amyloidosis LGE pattern. At the end of the follow-up (median 37 months, interquartile range 10–50 months), 31 patients (74%) had died. The hazard ratio for all-cause death was 3.2 (95% confidence interval [CI] 1.5–6.4, p < 0.01) for Group A versus Group B. Median survival time was 17 months (95% CI 7–42 months) for Group A and 70 months (95% CI 49–94 months) for Group B (p < 0.01). Multivariate analysis did not find any adjunctive predictive role for biventricular volumes and ejection fraction, indexed left ventricular mass, transmitral E/e’ at echocardiography, age at diagnosis or serum creatinine.

Conclusion

In our population, a typical LGE pattern was significantly associated with higher mortality. Moreover, patients with a typical LGE pattern showed a globally worse prognosis. Our data suggest that the LGE pattern may play a central role in prognostic stratification of patients with suspected CA, thus prompting further diagnostic and therapeutic measures.

     

Ecological characterization of a tick community across a landscape gradient exhibiting differential anthropogenic disturbance in the Atlantic Forest ecoregion in Argentina

An ecological analysis of a tick (Ixodida: Ixodidae) community across a landscape gradient presenting differential anthropogenic disturbance in the Atlantic Forest ecoregion in Argentina was performed. Ticks were collected from vegetation and hosts between September 2014 and August 2016. A total of 12 697 free‐living ticks and 3347 specimens from hosts were collected, including 317 ticks infesting humans. The values obtained show considerable species diversity in the forest environment accompanied by low equitability. The similarity index derived from a comparison of forest and agricultural environments was higher than that calculated by comparing forest and urban environments. The data suggest that although a cycle of one generation per year is apparent in some species, more than one cohort may co‐exist within the populations of some of these species. Well‐marked patterns of the seasonal distribution of free‐living tick species emerged in environments with no anthropic modification. The results indicate that forest environments are more suitable habitats than agricultural and urban environments for many species of native tick, but are unsuitable for exotic species that have successfully established in environments that have been modified by man.     

Enhanced production of scopolin bySolanum aviculare cells immobilised within Ca-alginate gel beads

Summary Different matrices, obtained by varying calcium (0.1 to 1.5M) and alginate (1 to 1.5%) concentrations, were used to study the influence of immobilisation parameters on the behaviour ofS. aviculare. A significant modulation of cell growth, cell release, and scopolin production and excretion has been observed. Physiological and morphological characteristics ofSolanum aviculare cells immobilised within Ca-alginate beads were notably different from those of suspended cells. ImmobilisedS. aviculare have accumulated scopolin (up to 120 g·g^–1 FWB) within beads and excreted it into the culture medium (up to 8 g·g^–1 FWB). Contrary to suspended cells which have accumulated only traces of this metabolite within intracellular compartments (1 g·g^–1 FWB), no scopolin has been found into the culture medium.Abbreviations ANA -Naphthaleneacetic acid - HPLC high performance liquid chromatography - FWB fresh weight biomass - LS medium Linsmaier and Skoog medium - MS mass spectroscopy - NMR nuclear magnetic resonance - r² coefficient of determination - s standard deviation