Publications by authors named "Bohorquez A"

Highly selective formal [4 + 2]-cycloaddition of vinyldiazoacetates with azoalkenes from α-halohydrazones, as well as with cyclopentadiene and furan, occurs with light irradiation at room temperature, producing highly functionalized heterocyclic and bicyclic compounds in good yields and excellent diastereoseletivity. Under blue light these vinyldiazoacetate reagents selectively form unstable cyclopropenes that undergo intermolecular cycloaddition reactions at a faster rate than their competitive ene dimerization. [4 + 2]-cycloaddition of vinyldiazoacetates with formed azoalkenes produces bicyclo[4.

View Article and Find Full Text PDF

In this study, two new nanohybrids (NH-A and NH-B) were synthesized through carbodiimide-assisted coupling. The reaction was performed between carboxymethyl-scleroglucans (CMS-A and CMS-B) with different degrees of substitution and commercial amino-functionalized silica nanoparticles using 4-(dimethylamino)-pyridine (DMAP) and N,N'-dicyclohexylcarbodiimide (DCC) as catalysts. The morphology and properties of the nanohybrids were investigated by using transmission (TEM) and scanning electron microscopy (SEM), electron-dispersive scanning (EDS), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FT-IR), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-OES), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic light scattering (DLS).

View Article and Find Full Text PDF

Alzheimer's disease (AD) is the leading cause of dementia worldwide. Numerous biomarker studies have clearly demonstrated that AD has a long asymptomatic phase, with the development of pathology occurring at least 2 decades prior to the development of any symptoms. These pathological changes include a stepwise development of amyloid-β (Aβ) plaques, followed by tau neurofibrillary tangles and subsequently extensive neurodegeneration in the brain.

View Article and Find Full Text PDF

Our objective was to improve the results of extracorporeal shock waves lithotripsy using hydroxycitric acid (HCA) like adjuvant therapy. Double blind randomized clinical trial using hydroxycitric acid versus placebo (ID NCT05525130). Multicenter study of adjuvant exposure to a food supplement with hydroxycitric acid (HCA), vs.

View Article and Find Full Text PDF

Spinal cord injury (SCI) results in severe cardiovascular dysfunction due to the disruption of supraspinal control. Autonomic dysreflexia (AD), an uncontrolled rise in blood pressure in response to peripheral stimuli including common bowel routine, digital anorectal stimulation (DARS), reduces the quality of life, and increases morbidity and mortality. Recently, spinal cord stimulation (SCS) has emerged as a potential intervention to mitigate unstable blood pressure following SCI.

View Article and Find Full Text PDF

In this report 5 compounds were synthesized and structural and their photophysical characterization was performed (Φ and Φ). Furthermore, in this in vitro study, their biological activity against Leishmania panamensis was evaluated. The photophysical behavior of these compounds was measured and high Φ and low Φ was observed.

View Article and Find Full Text PDF

Multidrug resistance (MDR) is one of the major factors in the failure of many chemotherapy approaches. In cancer cells, MDR is mainly associated with the expression of ABC transporters such as P-glycoprotein, MRP1 and ABCG2. Despite major efforts to develop new selective and potent inhibitors of ABC drug transporters, no ABCG2-specific inhibitors for clinical use are yet available.

View Article and Find Full Text PDF

Objectives: To test the hypotheses that (a) the chairside/handheld dental scanner combined with a metrology software will measure clinical wear in vivo in agreement with measurements from X-ray computed microtomography and; (b) polished monolithic zirconia does not cause accelerated wear of opposing enamel.

Materials And Methods: Thirty single crowns were randomized to receive a monolithic zirconia or metal-ceramic crown. Two non-restored opposing teeth in the same quadrants were identified to serve as enamel controls.

View Article and Find Full Text PDF

Aim: A 2016 Cochrane review showed that Kangaroo mother care (KMC) had a moderate impact on preterm growth, with high heterogeneity among studies. This systematic review and meta-analysis considered new evidence on KMC, particularly the duration.

Method: Databases were searched for papers published in English, French, Spanish and Portuguese up to 2017.

View Article and Find Full Text PDF

Cultures of Manduca sexta Johanssen in our laboratory were found to have larvae with missing or deformed mouthparts or antennae. Hypothesizing that these developmental deformities were caused by crowded rearing conditions, we reared larvae in four different population densities and recorded the incidence (% of larvae affected) and types of chemoreceptor deformities. Results showed that the incidence of these deformities was directly proportional to larval population density.

View Article and Find Full Text PDF

Aim: The aim of this study was to determine whether the Kangaroo position decreased apnoea events in preterm newborns compared with conventional care in incubator.

Methods: We conducted a systematic review of clinical trials published in English, French, Spanish and Portuguese. A comprehensive literature search was realised until 2017.

View Article and Find Full Text PDF

A series of 44 hybrid compounds that included in their structure tetrahydroquinoline (THQ) and isoxazole/isoxazoline moieties were synthesized through the 1,3-dipolar cycloaddition reaction (1,3-DC) from the corresponding -allyl/propargyl THQs, previously obtained via cationic Povarov reaction. In vitro cholinergic enzymes inhibition potential of all compounds was tested. Enzyme inhibition assays showed that some hybrids exhibited significant potency to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE).

View Article and Find Full Text PDF

Background: Brainstem gliomas are aggressive and difficult to treat. Growth of these tumors may be characterized with MRI methods.

Purpose: To visualize longitudinal changes in tumor volume, vascular leakiness, and tissue microstructure in an animal model of brainstem glioma.

View Article and Find Full Text PDF

Low tumor accumulation following systemic delivery remains a key challenge for advancing many cancer nanomedicines. One obstacle in engineering nanoparticles for high tumor accumulation is a lack of techniques to monitor their stability and mobility in situ. One way to monitor the stability and mobility of magnetic nanoparticles biological fluids in situ is through dynamic magnetic susceptibility measurements (DMS), which under certain conditions provide a measure of the particle's rotational diffusivity.

View Article and Find Full Text PDF

Magnetic alginate microspheres are biocompatible due to their alginate matrix, and motion-controllable by applied magnetic fields due to their magnetic character. Therefore, they have the potential of being used as vessels to a broad variety of materials, including drugs and therapeutic agents, facilitating entry to biological systems in a relatively non-invasive manner. Here, magnetic alginate microspheres were prepared through an emulsification and ionic cross-linking process, where a mixture of alginate and iron oxide magnetic nanoparticles was initially dispersed in a continuous phase, followed by gelation of this dispersed phase into microspheres by cross-linking the dispersion with calcium ions.

View Article and Find Full Text PDF

The rotational diffusion of polyethylene glycol coated magnetic nanoparticles in serum albumin solutions was investigated in a range spanning 0mgmL to 200mgmL. Rotational diffusivities were determined from dynamic magnetic susceptibility measurements, which provide a non-optical means to probe rotation of nanoparticles in small volume samples. Experimental rotational diffusivities were compared to those estimated using the Stokes-Einstein relation and macroscopic measurements of the viscosity of the protein solutions.

View Article and Find Full Text PDF

Given the geographical complexity of the Andes, species distributions hold interesting information regarding the history of isolation and gene flow across geographic barriers and ecological gradients. Moreover, current threats to the region's enormous plant diversity pose an additional challenge to the understanding of these patterns. We explored the geographic structure of genetic diversity within the Ceroxylon quindiuense species complex (wax palms) at a regional scale, using a model-based approach to disentangle the historical mechanisms by which these species have dispersed over a range encompassing 17° of latitude in the tropical Andes.

View Article and Find Full Text PDF

Introduction: Mental disorders are the first causes of disability adjusted life years (DALY), contributing with the 7.4%. This value increases as the DALYs of the transmittable diseases decrease.

View Article and Find Full Text PDF

Introduction: There was a prevalence of mental disorders of 17% in adolescents in the past year. These tended to be chronic and their appearance at this age is associated with a worse prognosis than those in adulthood.

Objectives: To determine the prevalence and mental factors associated with major depression and anxiety disorders.

View Article and Find Full Text PDF

Magnetic Fluid Hyperthermia (MFH) uses heat generated by magnetic nanoparticles exposed to alternating magnetic fields to cause a temperature increase in tumors to the hyperthermia range (43-47 °C), inducing apoptotic cancer cell death. As with all cancer nanomedicines, one of the most significant challenges with MFH is achieving high nanoparticle accumulation at the tumor site. This motivates development of synthesis strategies that maximize the rate of energy dissipation of iron oxide magnetic nanoparticles, preferable due to their intrinsic biocompatibility.

View Article and Find Full Text PDF

The objective of this study was to evaluate the status of anthelmintic resistance (AR) in ruminants and horses in Spain. The efficacy of commonly used macrocyclic lactones (MLs) - ivermectin (IVM) and moxidectin (MOX) - was measured in sheep, cattle and horses. In addition, albendazole (ABZ) and levamisole (LEV) were evaluated in sheep and oxibendazole (OXI) and pyrantel (PYR) in horses.

View Article and Find Full Text PDF

Current copro-diagnostic tests for Anoplocephala perfoliata show high variation in their sensitivity and given the morphological similarity of Anoplocephala spp. eggs, this could be related to the presence of Anoplocephala magna alone or co-existing with A. perfoliata.

View Article and Find Full Text PDF

Objective: This study aims to determine the clinical utility of visual ratings and volumetric measurements of medial temporal atrophy among subjects from the Alzheimer's Disease Neurorimaging Initiative (ADNI) cohort.

Methods: A sample of 189 subjects from the ADNI, Phase 1 (ADNI-1), was chosen as follows: 49 cognitively normal (CN), 89 with mild cognitive impairment (MCI), and 50 with Alzheimer's disease (AD). Structural MRI images were downloaded from the ADNI website, and a visual rating system (VRS) was used to obtain semi-quantitative ratings of the hippocampus (HPC) and entorhinal cortex (ERC).

View Article and Find Full Text PDF