Effects of online and offline trigeminal nerve stimulation on visuomotor learning.

Introduction: A current thrust in neurology involves using exogenous neuromodulation of cranial nerves (e.g, vagus, trigeminal) to treat the signs and symptoms of various neurological disorders. These techniques also have the potential to augment cognitive and/or sensorimotor functions in healthy individuals.

Expanding the antiprotozoal activity and the mechanism of action of n-butyl and iso-butyl ester of quinoxaline-1,4-di--oxide derivatives against , , and An and approach.

In this study, n-butyl and iso-butyl quinoxaline-7-carboxylate-1,4-di--oxide derivatives were evaluated against () (), and (). The potential mechanism of action determination was approached by analysis on and triosephosphate isomerase (TIM and TIM, respectively), and on thioredoxin reductase (). Enzyme inactivation assays were performed on recombinant GTIM and TrxR.

Improved serodiagnosis of Trypanosoma vivax infections in cattle reveals high infection rates in the livestock regions of Argentina.

Bovine trypanosomosis, caused by Trypanosoma vivax, currently affects cattle and has a significant economic impact in sub-Saharan Africa and South America. The development of new diagnostic antigens is essential to improve and refine existing methods. Our study evaluated the efficacy of two recombinant antigens in detecting specific antibodies in cattle.

Overoxidation and Oligomerization of Cytosolic and Mitochondrial Peroxiredoxins.

Peroxiredoxins (Prxs) have been shown to be important enzymes for trypanosomatids, counteracting oxidative stress and promoting cell infection and intracellular survival. In this work, we investigate the in vitro sensitivity to overoxidation and the overoxidation dynamics of Prxs in parasites in culture and in the infection context. We showed that recombinant m-TXNPx, in contrast to what was observed for c-TXNPx, exists as low molecular mass forms in the overoxidized state.

On the occurrence of a glutaredoxin-like small protein in the anaerobic protozoan parasite Entamoeba histolytica.

Background: Entamoeba histolytica, an intestinal parasitic protozoan that usually lives and multiplies within the human gut, is the causative agent of amoebiasis. To date, de novo glutathione biosynthesis and its associated enzymes have not been identified in the parasite. Cysteine has been proposed to be the main intracellular thiol.

Biochemical characterization of GAF domain of free-R-methionine sulfoxide reductase from Trypanosoma cruzi.

Trypanosoma cruzi is the causal agent of Chagas Disease and is a unicellular parasite that infects a wide variety of mammalian hosts. The parasite exhibits auxotrophy by L-Met; consequently, it must be acquired from the extracellular environment of the host, either mammalian or invertebrate. Methionine (Met) oxidation produces a racemic mixture (R and S forms) of methionine sulfoxide (MetSO).

Functional and structural characterization of an endo-β-1,3-glucanase from Euglena gracilis.

Endo-β-1,3-glucanases from several organisms have attracted much attention in recent years because of their capability for in vitro degrading β-1,3-glucan as a critical step for both biofuels production and short-chain oligosaccharides synthesis. In this study, we biochemically characterized a putative endo-β-1,3-glucanase (EgrGH64) belonging to the family GH64 from the single-cell protist Euglena gracilis. The gene coding for the enzyme was heterologously expressed in a prokaryotic expression system supplemented with 3% (v/v) ethanol to optimize the recombinant protein right folding.

Effects of Kilohertz Electrical Stimulation of the Trigeminal Nerve on Motor Learning.

Neurological disorders such as stroke remain leading causes of disability worldwide. A current thrust in the neurorehabilitation of such disorders involves exogenous neuromodulation of cranial nerves in order to enhance neuro-plasticity and maximize recovery of function. Here we present preliminary results on the effects of kilohertz range electrical stimulation of the trigeminal nerve (TNS) on motor learning, using an upper extremity visuomotor adaptation paradigm.

Functional characterization of monothiol and dithiol glutaredoxins from Leptospira interrogans.

Thiol redox proteins and low molecular mass thiols have essential functions in maintaining cellular redox balance in almost all living organisms. In the pathogenic bacterium Leptospira interrogans, several redox components have been described, namely, typical 2-Cys peroxiredoxin, a functional thioredoxin system, glutathione synthesis pathway, and methionine sulfoxide reductases. However, until now, information about proteins linked to GSH metabolism has not been reported in this pathogen.

The Cough Cold and Fever Clinic: A Model for the Safe Management of Ambulatory Patients With Suspected COVID-19.

Background And Objective: When the coronavirus disease-2019 (COVID-19) pandemic swept through New York City, hospital systems became quickly overwhelmed and ambulatory strategies were needed. We designed and implemented an innovative program called the Cough Cold and Fever (CCF) Clinic to safely triage, evaluate, treat, and follow up patients with symptoms concerning for COVID-19.

Methods: The CCF Clinic was launched on March 13, 2020, in the ambulatory internal medicine office of New York Presbyterian-Weill Cornell Medicine.

Full-thickness macular holes after surgical repair of primary rhegmatogenous retinal detachments: incidence, clinical characteristics, and outcomes.

Purpose: Full-thickness macular hole (FTMH) formation following rhegmatogenous retinal detachment (RRD) repair may limit post-operative visual acuity and often requires a return to the operating room, but little is known about this phenomenon.

Methods: This study included all patients with a FTMH that developed after RRD repair from January 1, 2015-July 31, 2020. The main outcome was the rate of FTMH formation following RRD repair as well as characteristics of FTMH following RRD repair that spontaneously close.

Elucidating carbohydrate metabolism in Euglena gracilis: Reverse genetics-based evaluation of genes coding for enzymes linked to paramylon accumulation.

Euglena gracilis is a eukaryotic single-celled and photosynthetic organism grouped under the kingdom Protista. This phytoflagellate can accumulate the carbon photoassimilate as a linear β-1,3-glucan chain called paramylon. This storage polysaccharide can undergo degradation to provide glucose units to obtain ATP and reducing power both in aerobic and anaerobic growth conditions.

Trypanothione Metabolism as Drug Target for Trypanosomatids.

Chagas Disease, African sleeping sickness, and leishmaniasis are neglected diseases caused by pathogenic trypanosomatid parasites, which have a considerable impact on morbidity and mortality in poor countries. The available drugs used as treatment have high toxicity, limited access, and can cause parasite drug resistance. Long-term treatments, added to their high toxicity, result in patients that give up therapy.

Functional characterization of methionine sulfoxide reductases from Leptospira interrogans.

Background: Methionine (Met) oxidation leads to a racemic mixture of R and S forms of methionine sulfoxide (MetSO). Methionine sulfoxide reductases (Msr) are enzymes that can reduce specifically each isomer of MetSO, both free and protein-bound. The Met oxidation could change the structure and function of many proteins, not only of those redox-related but also of others involved in different metabolic pathways.

On the functionality of a methionine sulfoxide reductase B from Trypanosoma cruzi.

Background: Methionine is an amino acid susceptible to be oxidized to give a racemic mixture of R and S forms of methionine sulfoxide (MetSO). This posttranslational modification has been reported to occur in vivo under either normal or stress conditions. The reduction of MetSO to methionine is catalyzed by methionine sulfoxide reductases (MSRs), thiol-dependent enzymes present in almost all organisms.

Effects of Contrast-Enhanced Ultrasound of Indeterminate Renal Masses on Patient Clinical Management: Retrospective Analysis From 2 Institutions.

Objectives: To investigate the long-term impact of contrast-enhanced ultrasound (CEUS) on the treatment of patients with indeterminate renal masses.

Methods: In this retrospective study, consecutive charts of all patients receiving renal CEUS at 1 of 2 academic medical centers between January 1, 2014, and December 31, 2018, were reviewed. Patients were included in the study if they had documented chronic renal disease (estimated glomerular filtration rate < 60 mL/min/1.

Conjunctival Melanoma: Features and Outcomes Based on the Fitzpatrick Skin Type in 540 Patients at a Single Ocular Oncology Center.

Purpose: To determine the association of Fitzpatrick skin type (FST) with conjunctival melanoma.

Methods: Retrospective case series of 540 patients with conjunctival melanoma to assess clinical features and outcomes per FST.

Results: The FST was Type I (n = 126, 23%), II (n = 337, 62%), III (n = 56, 10%), IV (n = 8, 2%), V (n = 12, 2%), and VI (n = 1, <1%).

Biological activity of esters of quinoxaline-7-carboxylate 1,4-di-N-oxide against E. histolytica and their analysis as potential thioredoxin reductase inhibitors.

Amoebiasis is caused by the protozoan Entamoeba histolytica that affects millions of people throughout the world. The standard treatment is metronidazole, however, this drug causes several side effects, and is also mutagenic and carcinogenic. Therefore, the search for therapeutic alternatives is necessary.

First evidence of glutathione metabolism in Leptospira interrogans.

Background: Glutathione (GSH) plays a role as a main antioxidant metabolite in all eukaryotes and many prokaryotes. Most of the organisms synthesize GSH by a pathway involving two enzymatic reactions, each one consuming one molecule of ATP. In a first step mediated by glutamate-cysteine ligase (GCL), the carboxylate of l-glutamic acid reacts with l-cysteine to form the dipeptide γ-glutamylcysteine (γ-GC).

Oligomerization dynamics and functionality of Trypanosoma cruzi cytosolic tryparedoxin peroxidase as peroxidase and molecular chaperone.

Background: Trypanosoma cruzi cytosolic tryparedoxin peroxidase (c-TXNPx) is a 2-Cys peroxiredoxin that plays an important role in coping with host cell oxidative response during the infection process, for which it has been described as a virulence factor.

Methods: Four residues corresponding to c-TXNPx catalytic and solvent-exposed cysteines were individually mutated to serine by site-specific mutagenesis. Susceptibility to redox treatments and oligomeric dynamics were investigated by western-blot and gel filtration chromatography.

Trypanothione synthetase confers growth, survival advantage and resistance to anti-protozoal drugs in Trypanosoma cruzi.

Background: Chagas cardiomyopathy, caused by Trypanosoma cruzi infection, continues to be a neglected illness, and has a major impact on global health. The parasite undergoes several stages of morphological and biochemical changes during its life cycle, and utilizes an elaborated antioxidant network to overcome the oxidants barrier and establish infection in vector and mammalian hosts. Trypanothione synthetase (TryS) catalyzes the biosynthesis of glutathione-spermidine adduct trypanothione (T(SH)) that is the principal intracellular thiol-redox metabolite in trypanosomatids.