Green nanoarchitectonics of carbon quantum dots from Cinchona Pubescens Vahl as targeted and controlled drug cancer nanocarrier.

Carbon quantum dots (CQDs) are a new carbon-based nanomaterial that has attracted tremendous attention due to their excellent fluorescent properties, chemical stability, water solubility, and biocompatibility features. Here, fluorescent CQDs synthesized by a green nanoarchitectonic method using Cinchona Pubescens Vahl extract were evaluated as drug nanocarriers for carboplatin (CBP) delivery. The characterization methods showed CQDs with semispherical shapes and sizes around 5 nm, temperature- and pH-dependent functional groups that interact with the CBP molecule adding specificity to the drug-delivery system. Based on the load efficiency results, it seems that the CQDs can carry almost 100 µg of carboplatin for every 1 mg of CQDs. This is possible due to the self-assembly process that takes place through the interaction between the protonation/deprotonation functional groups of CQDs and the hydrolyzed CBP molecule. Through this process, it is created spherical nanoparticles with an average size of 77.44 nm. The CQDs-CBP nanoparticles release the drug through a diffusion-controlled release mechanism where the acidic media is preferred, and the EPR effect also plays a helpful role. Besides, the viability test shows that the CQDs have almost null cytotoxicity suggesting that they could be used as a promising cancer treatment, improving the efficiency of cell internalization and significantly increasing their drug delivery.

Sargassum natans I Algae: An Alternative for a Greener Approach for the Synthesis of ZnO Nanostructures with Biological and Environmental Applications.

In this work, the influence of the Sargassum natans I alga extract on the morphological characteristics of synthesized ZnO nanostructures, with potential biological and environmental applications, was evaluated. For this purpose, different ZnO geometries were synthesized by the co-precipitation method, using Sargassum natans I alga extract as stabilizing agent. Four extract volumes (5, 10, 20, and 50 mL) were evaluated to obtain the different nanostructures. Moreover, a sample by chemical synthesis, without the addition of extract, was prepared. The characterization of the ZnO samples was carried out by UV-Vis spectroscopy, FT-IR spectroscopy, X-ray diffraction, and scanning electron microscopy. The results showed that the Sargassum alga extract has a fundamental role in the stabilization process of the ZnO nanoparticles. In addition, it was shown that the increase in the Sargassum alga extract leads to preferential growth and arrangement, obtaining well-defined shaped particles. ZnO nanostructures demonstrated significant anti-inflammatory response by the in vitro egg albumin protein denaturation for biological purposes. Additionally, quantitative antibacterial analysis (AA) showed that the ZnO nanostructures synthesized with 10 and 20 mL of extract demonstrated high AA against Gram (+) S. aureus and moderate AA behavior against Gram (-) P. aeruginosa, depending on the ZnO arrangement induced by the Sargassum natans I alga extract and the nanoparticles' concentration (ca. 3200 µg/mL). Additionally, ZnO samples were evaluated as photocatalytic materials through the degradation of organic dyes. Complete degradation of both methyl violet and malachite green were achieved using the ZnO sample synthesized with 50 mL of extract. In all cases, the well-defined morphology of ZnO induced by the Sargassum natans I alga extract played a key role in the combined biological/environmental performance.

Green Synthesis and Antiproliferative Activity of Gold Nanoparticles of a Controlled Size and Shape Obtained Using Shock Wave Extracts from Amphipterygium adstringens.

In this study, green chemistry was used as a tool to obtain gold nanoparticles using Amphipterygium adstringens extracts as a synthesis medium. Green ethanolic and aqueous extracts were obtained using ultrasound and shock wave-assisted extraction. Gold nanoparticles with sizes ranging between 100 and 150 nm were obtained with ultrasound aqueous extract. Interestingly, homogeneous quasi-spherical gold nanoparticles with sizes between 50 and 100 nm were achieved with shock wave aqueous-ethanolic extracts. Furthermore, 10 nm gold nanoparticles were obtained by the traditional methanolic macerate extraction method. The physicochemical characteristics, morphology, size, stability, and Z potential of the nanoparticles were determined using microscopic and spectroscopic techniques. The viability assay in leukemia cells (Jurkat) was performed using two different sets of gold nanoparticles, with final IC50 values of 87 µM and 94.7 µM, reaching a maximum cell viability decrease of 80% The results do not indicate a significant difference between the cytotoxic effects produced by the gold nanoparticles synthesized in this study and vincristine on normal lymphoblasts (CRL-1991).

Bimetallic AgPt Nanoalloys as an Electrocatalyst for Ethanol Oxidation Reaction: Synthesis, Structural Analysis, and Electro-Catalytic Activity.

In the present work, the chemical synthesis of AgPt nanoalloys is reported by the polyol method using polyvinylpyrrolidone (PVP) as a surfactant and a heterogeneous nucleation approach. Nanoparticles with different atomic compositions of the Ag and Pt elements (1:1 and 1:3) were synthesized by adjusting the molar ratios of the precursors. The physicochemical and microstructural characterization was initially performed using the UV-Vis technique to determine the presence of nanoparticles in suspension. Then, the morphology, size, and atomic structure were determined using XRD, SEM, and HAADF-STEM techniques, confirming the formation of a well-defined crystalline structure and homogeneous nanoalloy with an average particle size of less than 10 nm. Finally, the cyclic voltammetry technique evaluated the electrochemical activity of bimetallic AgPt nanoparticles supported on Vulcan XC-72 carbon for the ethanol oxidation reaction in an alkaline medium. Chronoamperometry and accelerated electrochemical degradation tests were performed to determine their stability and long-term durability. The synthesized AgPt (1:3)/C electrocatalyst presented significative catalytic activity and superior durability due to the introduction of Ag that weakens the chemisorption of the carbonaceous species. Thus, it could be an attractive candidate for cost-effective ethanol oxidation compared to commercial Pt/C.

Antibacterial and Anti-Inflammatory Properties of ZnO Nanoparticles Synthesized by a Green Method Using Sargassum Extracts.

The present work shows the synthesis of ZnO nanoparticles through a green method, using sargassum extracts, which provide the reducing and stabilizing compounds. The conditions of the medium in which the reaction was carried out was evaluated, that is, magnetic stirring, ultrasound assisted, and resting condition. UV-Vis, FTIR spectroscopy, and X-ray diffraction results confirmed the synthesis of ZnO with nanometric crystal size. The scanning electron microscopy analysis showed that the morphology and size of the particles depends on the synthesis condition used. It obtained particles between 20 and 200 nm in the sample without agitation, while the samples with stirring and ultrasound were 80 nm and 100 nm, respectively. ZnO nanoparticles showed antibacterial activity against Gram-positive S. aureus and Gram-negative P. aeruginosa. A quantitative analysis was performed by varying the concentration of ZnO nanoparticles. In all cases, the antibacterial activity against Gram-positives was greater than against Gram-negatives. Ultrasound-assisted ZnO nanoparticles showed the highest activity, around 99% and 80% for S. aureus and P. aeruginosa, respectively. Similar results were obtained in the study of the anti-inflammatory activity of ZnO nanoparticles; the ultrasound-assisted sample exhibited the highest percentage (93%), even above that shown by diclofenac, which was used as a reference. Therefore, the ZnO nanoparticles synthesized with sargassum extracts have properties that can be used safely and efficiently in the field of biomedicine.

Ecofriendly and sustainable Sargassum spp.-based system for the removal of highly used drugs during the COVID-19 pandemic.

Analgesic consumption increased significantly during the COVID-19 pandemic. A high concentration of this kind of drug is discarded in the urine, reaching the effluents of rivers, lakes, and seas. These medicines have brought serious problems for the flora and, especially, the ecosystems' fauna. This paper presents the results of removing diclofenac, ibuprofen, and paracetamol in an aqueous solution, using Sargassum spp. from the Caribbean coast. The study consisted of mixing each drug in an aqueous solution with functionalized Sargassum spp in a container under constant agitation. Therefore, this work represents an alternative to solve two of the biggest problems in recent years; first, the reduction of the overpopulation of sargassum through its use for the remediation of the environment. Second is the removal of drug waste used excessively during the COVID-19 pandemic. Liquid samples of the solution were taken at intervals of 10 min and analyzed by fluorescence to determine the concentration of the drug. The sorption capacity for diclofenac, ibuprofen, and paracetamol was 2.46, 2.08, and 1.41 µg/g, corresponding to 98 %, 84 %, and 54 % of removal, respectively. The removal of the three drugs was notably favored by increasing the temperature to 30 and 40 °C, reaching efficiencies close to 100 %. Moreover, the system maintains its effectiveness at various pH values. In addition, the Sargassum used can be reused for up to three cycles without reducing its removal capacity. The wide diversity of organic compounds favors the biosorption of drugs, removing them through various kinetic mechanisms. On the other hand, the Sargassum used in the drugs removal was analyzed by X-ray diffraction, FTIR spectroscopy, TGA analysis, and scanning electron microscopy before and after removal. The results showed an evident modification in the structure and morphology of the algae and demonstrated the presence of the biosorbed drugs. Therefore, this system is sustainable, simple, economical, environmentally friendly, highly efficient, and scalable at a domestic and industrial level that can be used for aquatic remediation environments.

Involuntary Emotional Expression Disorder in a Patient With Toluene Leukoencephalopathy.

OBJECTIVE: Inhalant users may develop toluene leukoencephalopathy, a devastating neuropsychiatric disorder. We present a case of toluene-induced damage to the corticospinal and the corticonuclear tracts, which presented with involuntary emotional expression disorder. METHODS: Case study of a 20-year-old man with a 3-year history of frequent solvent abuse was admitted to the Neuropsychiatry Unit of the National Institute of Neurology and Neurosurgery because "he could not speak or walk" but would keep "laughing and crying without reason". RESULTS: Neuropsychiatric examination revealed pathological laughter and crying, facial and speech apraxia, a bilateral pyramidal syndrome, and lack of control of urinary sphincter. Magnetic resonance imaging revealed a highly selective bilateral damage to the pyramidal system and the somatosensory pathway. SPECT imaging showed left fronto-parietal hypoperfusion. CONCLUSIONS: This document provides support for the understanding of involuntary emotional expression disorders as a differential diagnosis in the clinical practice of psychiatrists, as well as the functional anatomy of these conditions.

Involuntary Emotional Expression Disorder in a Patient With Toluene Leukoencephalopathy / Trastorno de expresión emocional involuntaria en un paciente con leucoencefalopatía por tolueno

ABSTRACT Objective: Inhalant users may develop toluene leukoencephalopathy, a devastating neuropsychiatric disorder. We present a case of toluene-induced damage to the corticospinal and the corticonuclear tracts, which presented with involuntary emotional expression dis-order. Methods: Case study of a 20-year-old man with a 3-year history of frequent solvent abuse was admitted to the Neuropsychiatry Unit of the National Institute of Neurology and Neurosurgery because "he could not speak or walk" but would keep "laughing and crying without reason". Results: Neuropsychiatric examination revealed pathological laughter and crying, facial and speech apraxia, a bilateral pyramidal syndrome, and lack of control of urinary sphincter. Magnetic resonance imaging revealed a highly selective bilateral damage to the pyramidal system and the somatosensory pathway. SPECT imaging showed left fronto-parietal hypoperfusion. Conclusions: This document provides support for the understanding of involuntary emotional expression disorders as a differential diagnosis in the clinical practice of psychiatrists, as well as the functional anatomy of these conditions.

RESUMEN Objetivo: Los usuarios de inhalantes pueden contraer leucoencefalopatía por tolueno, un trastorno neuropsiquiátrico devastador. Se presenta un caso de daño inducido por tolueno en el tracto corticoespinal y corticonuclear, que se manifestó con un trastorno involuntario de la expresión emocional. Métodos: Un varón de 20 años con antecedente de 3 años de abuso de solventes ingresó en la Unidad de Neuropsiquiatría del Instituto Nacional de Neurología y Neurocirugía porque «no podía hablar ni caminar¼ y presentaba episodios súbitos de risa y llanto sin razón aparente. Resultados: La valoración neuropsiquiátrica reveló risa y llanto patológicos, apraxia facial y fonatoria, síndrome piramidal bilateral y ausencia de control del esfínter urinario. La resonancia magnética cerebral mostró un daño bilateral muy selectivo del sistema piramidal y la vía somatosensorial. La imagen de tomografía computarizada por emisión monofotónica mostró hipoperfusión frontoparietal izquierda. Conclusiones: Este documento proporciona apoyo para la comprensión de los trastornos de la expresión emocional involuntaria como diagnóstico diferencial en la práctica clínica de los psiquiatras, así como de la anatomía funcional de estas condiciones.

Gelatin-Coated Magnetic Nanowires for High-Sensitivity Optical Labels.

The encapsulation of magnetic nickel nanowires (NiNWs) with gelatin is proposed as an alternative for optical label detection. Magnetic nanowires can be detected at very low concentrations using light-scattering methods. This detection capacity could be helpful in applications such as transducers for molecular and biomolecular sensors; however, potential applications require the attachment of specific binding molecules to the nanowire structure. In the present study, a method is presented which is helpful in coating magnetic nanowires with gelatin, a material with the potential to handle specific decoration and functionalization of the nanowires; in the first case, silver nanoparticles (AgNPs) are efficiently used to decorate the nanowires. Furthermore, it is shown that the synthesized gelatin-coated particles have excellent detectability to the level of 140 pg/mL; this level of detection outperforms more complex techniques such as ICP-OES (~3 ng/mL for Ni) and magnetoresistance sensing (~10 ng/mL for magnetic nanoparticles).

Green Synthesis of Homogeneous Gold Nanoparticles Using Sargassum spp. Extracts and Their Enhanced Catalytic Activity for Organic Dyes.

Sargassum species-based extracts were used to carry out the synthesis of homogeneous gold nanoparticles. Various techniques were used to determine the characteristics and composition of the nanoparticles. The UV-Vis results showed that the 50% water/ethanol extract had the most reducing agents and stabilizers. Therefore, this type of extract was used to synthesize nanoparticles and for their subsequent characterization. Crystallinity and crystal size were evaluated using X-ray diffraction. Size and morphology were analyzed using scanning electron microscopy, showing that the gold nanoparticles were mostly spherical, with a size range of 15-30 nm. The catalytic activity of the gold nanoparticles was evaluated through the degradation of organic dyes: methylene blue, methyl orange, and methyl red. The degradation rates were different, depending on the nature of each dye, the simplest to degrade was methylene blue and methyl red was the most difficult to degrade. The results indicated that the use of Sargassum spp. for the synthesis of gold nanoparticles has potential in the remediation of water that is contaminated with organic dyes. Moreover, given the recent serious environmental and economic problems caused by the overpopulation of Sargassum spp. in the Mexican Caribbean, the findings hold promise for their practical and sustainable use in the synthesis of nanomaterials.

Prevalence and Impact of Treatment-Resistant Depression in Latin America: a Prospective, Observational Study.

Approximately one-third of patients with major depressive disorder (MDD) have treatment-resistant depression (TRD). The TRAL study will evaluate the prevalence and impact of TRD among patients with MDD in four Latin American countries. In this multicenter, prospective, observational study, patients with MDD were recruited from 33 reference sites in Mexico, Colombia, Brazil, and Argentina. Patients were assessed for TRD, defined as failure to respond to ≥ 2 antidepressant medications of adequate dose and duration. Demographics, previous/current treatments, depressive symptoms, functioning, healthcare resource utilization, and work impairment were also collected and evaluated using descriptive statistics, chi-square test, Fisher exact test, t-test for independent samples, or the Mann-Whitney nonparametric test, as appropriate. 1475 patients with MDD were included in the analysis (mean age, 45.6 years; 78% women); 89% were receiving relevant psychiatric treatment. 429 patients met criteria for TRD, and a numerically higher proportion of patients with TRD was present in public versus private sites of care (31% vs 27%). The mean Montgomery-Asberg Depression Rating Scale score was 25.0 among all MDD patients and was significantly higher for patients with TRD versus non-TRD (29.4 vs 23.3; P < 0.0001). Patients with TRD, versus those with non-TRD, were significantly more likely to be older, have a longer disease duration, have more comorbidities, be symptomatic, have a higher median number of psychiatric consultations, and report greater work impairment. Patients with TRD have a disproportionate burden of disease compared to those with non-TRD. Appropriate treatment for TRD is a substantial unmet need in Latin America. https://www.ClinicalTrials.gov identifier NCT03207282, 07/02/2017.

Differences in quality of life between genders in acromegaly.

Objective: To study the impact of secondary mental disorders in patients affected with acromegaly and correlate them with quality of life (QoL) and disease status. Design: An observational transversal descriptive and comparative study that evaluates QoL's impact due to secondary mental disorders in affected Mexicans with acromegaly using AcroQoL and SF-36 instruments. Correlation of the results with the disease's biochemical status was performed. According to Beck's scales, anxiety and depression analyses evaluate QoL's impact, and its gender variability is described. Results: Eighty-five patients with diagnoses of acromegaly were included. The mean age was 43.18 years, 47 being women (55.29%). The mean age at diagnosis was 37.95 years, with no difference between men and women. AcroQoL and SF-36 global and sub-domain scores differed significantly between men and women, the latter having lower global and individual sub-domain scores. The mean score of QoL, according to AcroQoL, is 59.40. In women, the mean values are less (55.13) than men (64.68), p = 0.021. The sub-domain analyses' scores in physical, appearance and social relationships were less in women (53.21; 47.34; 62.32) than men (62.68; 56.76; 73.87) p = 0.044, 0.069 and 0.013, respectively. Higher Beck's Depression Inventory (BDI) and Beck's Anxiety Inventory (BAI) scores correlated with lower QoL as assessed by global and individual sub-domain scores. Women presented significantly higher BDI and BAI mean scores when compared to men regardless of their biochemical status. Anxiety (p = 0.027) and depression (p < 0.001) severity were higher in women compared to men. Conclusion: Correlations between female gender, depression/anxiety scores and QoL require further validation. There is much to be routinely done to improve secondary psychopathology in patients affected by this disease. The need for mental status screening at diagnosis should be emphasized to identify secondary mental illnesses to improve QoL with its treatment.

Developing a CNT-SPE Sensing Platform Based on Green Synthesized AuNPs, Using Sargassum sp.

Detection and quantification of diverse analytes such as molecules, cells receptor and even particles and nanoparticles, play an important role in biomedical research, particularly in electrochemical sensing platform technologies. In this study, gold nanoparticles (AuNPs) prepared by green synthesis from Sargassum sp. were characterized using ultraviolet-visible (UV-Vis) and Fourier transform-infrared (FT-IR) spectroscopies, X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS) and zeta potential (ζ) obtaining organic capped face-centered cubic 80-100 nm AuNPs with an excellent stability in a wide range of pH. The AuNPs were used to modify a carbon nanotubes-screen printed electrode (CNT-SPE), through the drop-casting method, to assemble a novel portable electrochemical sensing platform for glucose, using a novel combination of components, which together have not been employed. The ability to sense and measure glucose was demonstrated, and its electrochemical fundamentals was studied using cyclic voltammetry (CV). The limits of detection (LOD) and quantification (LOQ) to glucose were 50 µM and 98 µM, respectively, and these were compared to those of other sensing platforms.

Controlled Fabrication of Flower-Shaped Au-Cu Nanostructures Using a Deep Eutectic Solvent and Their Performance in Surface-Enhanced Raman Scattering-Based Molecular Sensing.

Controlled synthesis of anisotropic bimetallic nanostructures with tunable morphology is of great current interest for their applications in surface-enhanced Raman scattering (SERS), plasmonics, and catalysis. Despite huge effort that has been devoted so far, fabrication of bimetallic nanostructures with controlled morphology and size remained to be a great challenge, especially when their shapes are anisotropic. Here, we report a facile, one-step synthetic approach for the fabrication of anisotropic bimetallic gold-copper nanostructures (Au-Cu NSs) of the 200-300 nm size range, using choline chloride/urea (ChCl/urea)-based deep eutectic solvent (DES) as the soft template. A concentration of the CuCl2 precursor in the reaction mixture was found to impact the reduction kinetics of the metal ions, directly affecting the final morphology of the Au-Cu nanostructures and elemental distributions in them. The fabricated anisotropic Au-Cu NSs revealed a high SERS signal for crystal violet (CV) molecules adsorbed at their surfaces, with the signal enhancement factor as high as 0.21 × 106 and capacity of detecting CV molecules of concentrations as low as 10-10 M in their aqueous solutions. The growth mechanism of the anisotropic bimetallic nanostructures in DES and their SERS performance has been discussed. The simple DES-assisted synthesis strategy presented in this work can be adopted for large-scale nonaqueous fabrication of other bimetallic nanostructures in a quite "greener" way.

Deep-brain stimulation in treatment-resistant obsessive-compulsive disorder: Clinical and molecular neuroimaging correlation / Estimulación cerebral profunda en el trastorno obsesivo compulsivo resistente a tratamiento: correlato clínico y de neuroimagen molecular

ABSTRACT Introduction: Obsessive-compulsive disorder is defined by the presence of obsessions and compulsions that cause marked anxiety or distress and has been associated with a disruption in corticostriato-thalamo-cortical circuitry. After treatment, around 50% of patients continue to experience incapacitating symptoms. Deep-brain stimulation has been shown to be an effective therapeutic alternative to regular treatment. Methods: Case report. Case presentation: A 54-year-old woman with a diagnosis of treatment-resistant obsessive-compulsive disorder was treated with deep-brain stimulation of the anterior limb of the internal capsule. Molecular imaging before and after the procedure was obtained and correlated with clinical features. Conclusions: Deep-brain stimulation may be a therapeutic alternative to regular care in treatment-resistant obsessive-compulsive disorder and can be correlated to functional changes in suspected anatomical structures.

RESUMEN Introducción: El trastorno obsesivo-compulsivo se define por la presencia de obsesiones y compulsiones que ocasionan ansiedad y malestar marcados, y se ha asociado con una alteración en los circuitos cortico-estriado-tálamo-corticales. Tras tratamiento, alrededor de la mitad de los pacientes permanecen con síntomas discapacitantes. La estimulación cerebral profunda ha mostrado ser una alternativa efectiva al tratamiento usual. Métodos: Reporte de caso. Presentación del caso: Una mujer de 54 años con diagnóstico de trastorno obsesivo-compulsivo resistente a tratamiento fue tratada con estimulación cerebral profunda del brazo anterior de la cápsula interna. Se obtuvieron imágenes moleculares antes y después de la intervención y fueron correlacionadas con el cuadro clínico. Conclusiones: La estimulación magnética profunda puede ser una alternativa terapéutica al tratamiento usual en el trastorno obsesivo compulsivo resistente a tratamiento, y puede correlacionarse con cambios funcionales en estructuras anatómicas de sospecha.

Deep-brain stimulation in treatment-resistant obsessive-compulsive disorder: Clinical and molecular neuroimaging correlation.

INTRODUCTION: Obsessive-compulsive disorder is defined by the presence of obsessions and compulsions that cause marked anxiety or distress and has been associated with a disruption in cortico-striato-thalamo-cortical circuitry. After treatment, around 50% of patients continue to experience incapacitating symptoms. Deep-brain stimulation has been shown to be an effective therapeutic alternative to regular treatment. METHODS: Case report. CASE PRESENTATION: A 54-year-old woman with a diagnosis of treatment-resistant obsessive-compulsive disorder was treated with deep-brain stimulation of the anterior limb of the internal capsule. Molecular imaging before and after the procedure was obtained and correlated with clinical features. CONCLUSIONS: Deep-brain stimulation may be a therapeutic alternative to regular care in treatment-resistant obsessive-compulsive disorder and can be correlated to functional changes in suspected anatomical structures.

Ketamina, un nuevo agente terapéutico para la depresión / Ketamine, a New Therapeutic Agent for Depression

Resumen: El trastorno depresivo mayor (TDM) afecta aproximadamente a una de cada 10 personas en México y es una de las primeras 5 causas de discapacidad a nivel global. Las opciones de tratamiento actuales son limitadas debido a que solo actúan en algunos de los factores fisiopatológicos relacionados con esta enfermedad, además de que los efectos sobre la depresión suelen ser retardados. Esto implica una importante limitación en disminuir la discapacidad que origina e impide una acción rápida ante la ideación suicida. Recientemente, la ketamina (un anestésico) ha probado tener propiedades antidepresivas a través de su actividad sobre el sistema de neurotransmisión glutamatérgica (ningún otro tratamiento actúa a este nivel). Logra mejoría de los síntomas depresivos en horas y ha resultado útil en pacientes que no responden a los tratamientos disponibles en la actualidad. Recientemente se aprobó su utilización para el tratamiento de este trastorno. Sin embargo, aún quedan interrogantes sobre sus mecanismos de acción antidepresiva, seguridad y efectos secundarios, entre otros.

Abstract: Major depressive disorder affects about one in every 10 people in Mexico and is one of the first 5 causes of disability worldwide. Current treatment options are limited and only act upon some factors associated in its physiopathology. Moreover, the effects on depression are not immediate, which is a great limitation in obtaining a benefit over disability caused by this disorder and impedes a rapid action in the scenario of suicidality. Recently, ketamine (an anesthetic) has shown to have antidepressant properties by acting in the glutamate neurotransmission system (while no other current treatment acts on this level). It offers benefits in depressive symptoms in a matter of hours and has proven to be useful in patients that do not benefit from current therapeutic options. Recently, it has been approved for the treatment of depression. However, there are still many questions about its antidepressant mechanisms of action, safety, side effects, among others.

Ketamine as augmentation for the treatment of major depression and suicidal risk in advanced cancer: Case report.

OBJECTIVE: Major depressive disorder (MDD) is common in patients diagnosed with advanced cancer (AC), with a prevalence of 16.5%. It is associated with great disability and worsened quality of life, increased number and intensity of physical symptoms, and lower survival. It is the main factor for the presence of suicidal ideation. Antidepressants show modest efficacy, and response requires several weeks. Ketamine has demonstrated a fast and robust antidepressant effect in subanesthetic doses. This effect may prove useful in patients with AC, MDD, and suicidal risk. METHOD: We report a case of a patient with advanced cervical cancer who presented with uncontrollable pain, MDD, and a suicide attempt. RESULT: A 39-year-old woman diagnosed with cervical cancer stage IVB presented to the Emergency Department after a suicide attempt by hanging. Upon evaluation by the palliative care psychiatrist, she reported intense pain, unresponsive to analgesics, and had a history of persistent suicidal ideation. Antidepressant treatment was started (sertraline 50mg/d) after a single dose of ketamine hydrochloride IV (0.5 mg/kg) was administered. Treatment response was measured using the Brief Edinburgh Depression Scale before and after the intervention. The depressive symptoms decreased by 17% on day 1, 39% on day 3, and 72% on day 17. SIGNIFICANCE OF RESULTS: This case report shows ketamine's efficacy as an augmentation agent alongside conventional antidepressant treatment in patients with AC. Moreover, it shows rapid response in suicidal ideation that has not been achieved with treatment as usual. More clinical trials are needed to support the potential benefit and safety of ketamine in patients with AC, MDD, and persisting suicidal ideation.

Involuntary Emotional Expression Disorder in a Patient With Toluene Leukoencephalopathy.

OBJECTIVE: Inhalant users may develop toluene leukoencephalopathy, a devastating neuropsychiatric disorder. We present a case of toluene-induced damage to the corticospinal and the corticonuclear tracts, which presented with involuntary emotional expression disorder. METHODS: Case study of a 20-year-old man with a 3-year history of frequent solvent abuse was admitted to the Neuropsychiatry Unit of the National Institute of Neurology and Neurosurgery because "he could not speak or walk" but would keep "laughing and crying without reason". RESULTS: Neuropsychiatric examination revealed pathological laughter and crying, facial and speech apraxia, a bilateral pyramidal syndrome, and lack of control of urinary sphincter. Magnetic resonance imaging revealed a highly selective bilateral damage to the pyramidal system and the somatosensory pathway. SPECT imaging showed left fronto-parietal hypoperfusion. CONCLUSIONS: This document provides support for the understanding of involuntary emotional expression disorders as a differential diagnosis in the clinical practice of psychiatrists, as well as the functional anatomy of these conditions.

Synthesis of Au@Pt Core-Shell Nanoparticles as Efficient Electrocatalyst for Methanol Electro-Oxidation.

Bimetallic Au@Pt nanoparticles (NPs) with Pt monolayer shell are of much interest for applications in heterogeneous catalysts because of enhanced catalytic activity and very low Pt-utilization. However, precisely controlled synthesis with uniform Pt-monolayers and stability on the AuNPs seeds remain elusive. Herein, we report the controlled deposition of Pt-monolayer onto uniform AuNPs seeds to obtain Au@Pt core-shell NPs and their Pt-coverage dependent electrocatalytic activity for methanol electro-oxidation. The atomic ratio between Au/Pt was effectively tuned by varying the precursor solution ratio in the reaction solution. The morphology and atomic structure of the Au@Pt NPs were analyzed by high-resolution scanning transmission electron microcopy (HR-STEM) and X-ray diffraction (XRD) techniques. The results demonstrated that the Au@Pt core-shell NPs with Pt-shell thickness (atomic ratio 1:2) exhibit higher electrocatalytic activity for methanol electro-oxidation reaction, whereas higher and lower Pt ratios showed less overall catalytic performance. Such higher catalytic performance of Au@Pt NPs (1:2) can be attributed to the weakened CO binding on the Pt/monolayers surface. Our present synthesis strategy and optimization of the catalytic activity of Au@Pt core-shell NPs catalysts provide promising approach to rationally design highly active catalysts with less Pt-usage for high performance electrocatalysts for applications in fuel cells.