The parietal cortex has a causal role in ambiguity computations in humans.

Humans often face the challenge of making decisions between ambiguous options. The level of ambiguity in decision-making has been linked to activity in the parietal cortex, but its exact computational role remains elusive. To test the hypothesis that the parietal cortex plays a causal role in computing ambiguous probabilities, we conducted consecutive fMRI and TMS-EEG studies. We found that participants assigned unknown probabilities to objective probabilities, elevating the uncertainty of their decisions. Parietal cortex activity correlated with the objective degree of ambiguity and with a process that underestimates the uncertainty during decision-making. Conversely, the midcingulate cortex (MCC) encodes prediction errors and increases its connectivity with the parietal cortex during outcome processing. Disruption of the parietal activity increased the uncertainty evaluation of the options, decreasing cingulate cortex oscillations during outcome evaluation and lateral frontal oscillations related to value ambiguous probability. These results provide evidence for a causal role of the parietal cortex in computing uncertainty during ambiguous decisions made by humans.

Use of hepatic support with MARS in a patient with SARS-CoV-2 Pneumonia, in treatment with ECMO and CRRT therapies: Case Report.

Extracorporeal Membrane Oxygenation (ECMO) therapy had an important role in the treatment of severe COVID-19 pneumonia, where invasive mechanical ventilation was not enough to provide correct oxygenation to various organ systems. However, there are other extracorporeal technologies, such as the Molecular Absorbent Recirculation System (MARS) and Continuous Renal Replacement Therapy (CRRT), that provide temporal support for any critical patient. The following case describes a 60-year-old man with severe Acute Respiratory Distress Syndrome (ARDS), who needed ECMO therapy. During the critical days of hospitalization, CRRT was used, but a sudden hyperbilirubinemia ensued. Consequently, MARS therapy was initiated; followed by an improvement of bilirubin levels. Additional studies are needed to establish the possible benefits of the combination of MARS therapy and ECMO; however, we detected that concomitantly, there was a decrease in other laboratory parameters such as acute phase reactants. Even though, no change in clinical course was observed, as shown in some studies.

Neurogenic diabetes insipidus in a critical patient with COVID-19 pneumonia in treatment with extracorporeal membrane oxygenation: a case report.

The following case report analyses a patient with extracorporeal membrane oxygenation (ECMO), who suffered from a severe Acute Respiratory Distress Syndrome (ARDS) due to COVID-19 pneumonia. ARDS is defined as a diffuse and inflammatory injury of the lungs; classifying this as severe when the ratio of arterial oxygen tension to a fraction of inspired oxygen (PaO2/FiO2) is equal to or lower than 100 mmHg. To decide if the patient was suitable for the use of ECMO therapy, the ELSO criteria were used; and in this case, the patient matched with the criteria of hypoxemic respiratory failure (with a PaO2/FiO2 < 80 mmHg) after optimal medical management, including, in the absence of contraindications, a trial of prone positioning. During hospitalization, the patient presented a Central Diabetes Insipidus (CDI), probably explained by the damage hypoxia generated on the central nervous system. There are few reports of this complication produced by COVID-19. The case is about a 39-year-old woman, who started with ECMO 6 days after the beginning of Invasive Mechanical Ventilation (IMV), because of a severe ARDS. On the fifth day of ECMO, the patient started with a polyuria of 7 L in 24 h. A series of paraclinical studies were made, but no evidence of central nervous system lesions was found. After treatment with desmopressin was initiated and the ARDS was solved, polyuria stopped; with this, CDI was diagnosed. There are many complications secondary to the evolution of COVID-19 infection, and some of them are not yet well explained.

Epithelioid Kaposi Sarcoma: A New Histological Variant.

ABSTRACT: Cutaneous Kaposi sarcoma (KS) covers a broad spectrum both clinically and pathologically. Some histological patterns of KS may be difficult to recognize and must be differentiated from other vascular neoplasms. We report on a 56-year-old Peruvian man who had been diagnosed with classical KS on the right foot 2 years before the present episode. He presented in our clinic with new lesions on the left foot. Histopathological findings included areas showing epithelioid cells with moderate pleomorphism, growing in solid sheets. Immunohistochemistry showed strong nuclear staining with a granular nuclear staining pattern for human herpesvirus 8 in the epithelioid cells. A diagnosis of epithelioid Kaposi sarcoma was made, which should be considered a new histological variant.

Chronic viral hepatitis C micro-elimination program using telemedicine. The Mexican experience.

In response to the kind letter from Joaquín Cabezas et al., we agree that medical care in the COVID era has radically changed and using new mechanisms in the care of different diseases is undoubtedly now a priority to avoid contagion of both the patient and the medical staff. Although a vaccine could protect the population, there are still many questions to answer. The model we use for the care of patients with a diagnosis of hepatitis C virus (HCV) in Mexico showed great benefits, as in other studies.

COVID-19 epidemiology in a Mexican tertiary care hospital.

INTRODUCTION: As a result of COVID-19, many hospitals underwent a conversion for the care for this disease. OBJECTIVE: To analyze COVID-19 hospital epidemiological behavior from March to August 2020. METHODS: Through a series of cases, COVID-19 epidemiological behavior at the hospital was analyzed, for which simple case rates, percentages and incidence of COVID-19 per 100 hospital discharges were estimated. RESULTS: Out of 491 subjects who tested positive for SARS-CoV-2, 156 (31.7 %) were hospitalized for clinical data of moderate to severe disease. Average age was 59.1 years; 121 cases (75 %) were discharged due to improvement, and 32 (20.5 %), due to death. Average age of those who died was 69.7 years, and the most affected age group was 60 to 80 years (45.4 %). Calculated lethality was 20.5 per 100 hospital discharges, while that calculated taking into account positive patients (outpatients and hospitalized patients) was 6.5. CONCLUSIONS: COVID-19 epidemiological behavior was similar to that described in other studies; however, lethality and mortality are above national average. The analysis of this and of the factors that favored it in our population is pending.

INTRODUCCIÓN: A consecuencia de COVID-19, numerosos hospitales sufrieron una reconversión para la atención de esta enfermedad. OBJETIVO: Analizar el comportamiento epidemiológico hospitalario de COVID-19 entre marzo y agosto de 2020. MÉTODOS: En una serie de casos se analizó el comportamiento epidemiológico de COVID-19 en un hospital de tercer nivel, para lo cual se estimaron frecuencias simples de casos, porcentajes e incidencia por cada 100 egresos hospitalarios. RESULTADOS: De 491 sujetos con prueba positiva para SARS-CoV-2, 156 (31.7 %) fueron hospitalizados por datos clínicos de enfermedad moderada a grave. La edad promedio fue de 59.1 años; 121 casos (75 %) egresaron por mejoría y 32 (20.5 %), por defunción. El promedio de edad de quienes fallecieron fue de 69.7 años y el grupo etario más afectado fue el de 60 a 80 años (45.4 %). La letalidad calculada fue de 20.5 por 100 egresos hospitalarios, mientras que la calculada tomando en cuenta los pacientes positivos (ambulatorios y hospitalizados) fue de 6.5. CONCLUSIONES: El comportamiento epidemiológico de COVID-19 fue similar al descrito en otros estudios; sin embargo, la letalidad y la mortalidad están por encima de la media nacional. Está pendiente el análisis de estas y de los factores que las favorecieron en nuestra población.

Opportunities in the teaching of medical specialties, regarding influenza and COVID-19.

Medical specialties' teaching is an area of health systems that deserves special consideration in light of the lessons learned from influenza and COVID-19; educational programs and implementation of the training strategies that are used must be reevaluated, since the level of training of most specialty students does not allow to consider them as personnel who can face these global problems. The number of specialization courses has exponentially grown, and their main threat is the cancellation or partial execution of their academic programs as a consequence of not implementing functional operational strategies during a contingency.

La enseñanza en las especialidades médicas es un rubro de los sistemas de salud que merece consideraciones especiales de acuerdo con las lecciones aprendidas de la influenza y COVID-19. Deben reevaluarse los programas educativos y las estrategias de capacitación implementadas, ya que la preparación escolar de la mayoría de los alumnos no les permite ser considerados como personal que pueda enfrentar esos problemas globales. Los cursos de especialización han crecido en número, pero su principal amenaza es la suspensión de los programas académicos o que sean parcialmente cubiertos como consecuencia de no implementar estrategias operativas funcionales durante una contingencia.

Evaluation of medical ethics competencies in rheumatology: local experience during national accreditation process.

INTRODUCTION: Rheumatologists are the primary healthcare professionals responsible for patients with rheumatic diseases and should acquire medical ethical competencies, such as the informed consent process (ICP). The objective clinical structured examination is a valuable tool for assessing clinical competencies. We report the performance of 90 rheumatologist trainees participating in a station designed to evaluate the ICP during the 2018 and 2019 national accreditations. METHODS: The station was validated and represented a medical encounter in which the rheumatologist informed a patient with systemic lupus erythematosus with clinically active nephritis about renal biopsy. A trained patient-actor and an evaluator were instructed to assess ICP skills (with a focus on kidney biopsy benefits, how the biopsy is done and potential complications) in obtaining formal informed consent, delivering bad news and overall communication with patients. The evaluator used a tailored checklist and form. RESULTS: Candidate performance varied with ICP content and was superior for potential benefit information (achieved by 98.9% of the candidates) but significantly reduced for potential complications (37.8%) and biopsy description (42.2%). Only 17.8% of the candidates mentioned the legal perspective of ICP. Death (as a potential complication) was omitted by the majority of the candidates (93.3%); after the patient-actor challenged candidates, only 57.1% of them gave a clear and positive answer. Evaluators frequently rated candidate communications skills as superior (≥80%), but ≥1 negative aspect was identified in 69% of the candidates. CONCLUSIONS: Ethical competencies are mandatory for professional rheumatologists. It seems necessary to include an ethics competency framework in the curriculum throughout the rheumatology residency.

G6PD deficiency, primaquine treatment, and risk of haemolysis in malaria-infected patients.

BACKGROUND: The incidence of malaria in the Americas has decreased markedly in recent years. Honduras and the other countries of Mesoamerica and the island of Hispaniola have set the goal of eliminating native malaria by the year 2020. To achieve this goal, Honduras has recently approved national regulations to expand the possibilities of a shortened double dose primaquine (PQ) treatment for vivax malaria. Considering this new shortened anti-malarial treatment, the high frequency of G6PDd genotypes in Honduras, and the lack of routinely assessment of the G6PD deficiency status, this study aimed at investigating the potential association between the intake of PQ and haemolysis in malaria-infected G6PDd subjects. METHODS: This was a prospective cohort and open-label study. Participants with malaria were recruited. Plasmodium vivax infection was treated with 0.25 mg/kg of PQ daily for 14 days. Safety and signs of haemolysis were evaluated by clinical criteria and laboratory values before and during the 3rd and 7th day of PQ treatment. G6PD status was assessed by a rapid test (CareStart™) and two molecular approaches. RESULTS: Overall 55 participants were enrolled. The frequency of G6PD deficient genotypes was 7/55 (12.7%), where 5/7 (71.4%) were hemizygous A- males and 2/7 (28.6%) heterozygous A- females. Haemoglobin concentrations were compared between G6PD wild type (B) and G6PDd A- subjects, showing a significant difference between the means of both groups in the 3rd and 7th days. Furthermore, a statistically significant difference was evident in the change in haemoglobin concentration between the 3rd day and the 1st day for both genotypes, but there was no statistical difference for the change in haemoglobin concentration between the 7th day and the 1st day. Besides these changes in the haemoglobin concentrations, none of the patients showed signs or symptoms associated with severe haemolysis, and none needed to be admitted to a hospital for further medical attention. CONCLUSIONS: The findings support that the intake of PQ during 14 days of treatment against vivax malaria is safe in patients with a class III variant of G6PDd. In view of the new national regulations in the shortened treatment of vivax malaria for 7 days, it is advisable to be alert of potential cases of severe haemolysis that could occur among G6PD deficient hemizygous males with a class II mutation such as the Santamaria variant, previously reported in the country.

Cost-minimization study comparing annual infusion of zoledronic acid or weekly oral alendronate in women with low bone mineral density.

Cost-minimization study to assess the annual direct costs of 2 antiresorptive strategies in postmenopausal women with low bone mineral densities (BMDs). Patients were randomly assigned to receive 70 mg of oral weekly alendronate or a 1-time 5mg of intravenous zoledronic acid. All medical and nonmedical direct costs were recorded for 1 yr. Student's t-test or the Chi-squared test was used. A total of 101 postmenopausal women were enrolled with a mean age of 58.3 ± 7.6 yr and a postmenopausal period of 13.5 ± 8.3 yr. A total of 50 patients completed 1 yr of alendronate and 51 patients received zoledronic acid. At baseline, no differences were seen between the 2 groups in anthropometric measures, comorbidities, and bone mineral density. The costs for medical attention for low bone mass were $81,532 (US Dollars) for the alendronate group and $69,251 for the zoledronic acid group; the cost per patient was $1631 in the alendronate group vs $1358 in the zoledronic acid group (p<0.0001). Therefore, zoledronic acid treatment provided an annual savings of 15% of the direct costs compared with oral alendronate treatment. Moreover, there was a significant increase in lumbar spine T-scores in the zoledronic acid group when compared with the alendronate group. Annual zoledronic acid infusion as an antiresorptive treatment in women with low BMD provides significant monetary savings when compared with weekly alendronate therapy for 1 yr. Zoledronic acid infusion is also linked to higher increase in BMD and compliance.

Update of the guidelines for the pharmacological treatment of rheumatoid arthritis by the Mexican College of Rheumatology 2023.

OBJECTIVE: To develop updated guidelines for the pharmacological management of rheumatoid arthritis (RA). METHODS: A group of experts representative of different geographical regions and various medical services catering to the Mexican population with RA was formed. Questions based on Population, Intervention, Comparison, and Outcome (PICO) were developed, deemed clinically relevant. These questions were answered based on the results of a recent systematic literature review (SLR), and the evidence's validity was assessed using the GRADE system, considered a standard for these purposes. Subsequently, the expert group reached consensus on the direction and strength of recommendations through a multi-stage voting process. RESULTS: The updated guidelines for RA treatment stratify various therapeutic options, including different classes of DMARDs (conventional, biologicals, and JAK inhibitors), as well as NSAIDs, glucocorticoids, and analgesics. By consensus, it establishes the use of these in different subpopulations of interest among RA patients and addresses aspects related to vaccination, COVID-19, surgery, pregnancy and lactation, and others. CONCLUSIONS: This update of the Mexican guidelines for the pharmacological treatment of RA provides reference points for evidence-based decision-making, recommending patient participation in joint decision-making to achieve the greatest benefit for our patients. It also establishes recommendations for managing a variety of relevant conditions affecting our patients.

Cutaneous gnathostomiasis: report of 6 cases with emphasis on histopathological demonstration of the larva.

BACKGROUND: Cutaneous gnathostomiasis is an emerging food-borne parasitic zoonosis. Histopathological demonstration of the larva on random biopsy specimen of erythematous plaques is infrequent because of its migrating nature. OBJECTIVE: We sought to determine whether medical treatment with albendazole or ivermectin increases the diagnostic yield of skin biopsy specimen. METHODS: A retrospective chart review was conducted in a private dermatology practice in Lima, Peru. Cases with a clinical diagnosis of nodular migratory panniculitis and pathological diagnosis of eosinophilic panniculitis or gnathostomiasis were reviewed. Only cases with definitive diagnosis confirmed by histopathology or parasite isolation were included in the study. RESULTS: A definitive diagnosis of gnathostomiasis was rendered in 6 of 55 reviewed cases. Histopathological or gross identification of the nematode's larva was made obtaining a biopsy specimen of papules or pseudofuruncles that developed after oral antiparasitic treatment. LIMITATIONS: This is a retrospective case series study and no serologic testing was available. CONCLUSION: Biopsy of a papule or pseudofuruncle subsequent to oral treatment increases the likelihood of demonstrating the larva on skin biopsy specimen, which allows definitive diagnosis and may have therapeutic benefit.

A real-time fMRI neurofeedback system for the clinical alleviation of depression with a subject-independent classification of brain states: A proof of principle study.

Most clinical neurofeedback studies based on functional magnetic resonance imaging use the patient's own neural activity as feedback. The objective of this study was to create a subject-independent brain state classifier as part of a real-time fMRI neurofeedback (rt-fMRI NF) system that can guide patients with depression in achieving a healthy brain state, and then to examine subsequent clinical changes. In a first step, a brain classifier based on a support vector machine (SVM) was trained from the neural information of happy autobiographical imagery and motor imagery blocks received from a healthy female participant during an MRI session. In the second step, 7 right-handed female patients with mild or moderate depressive symptoms were trained to match their own neural activity with the neural activity corresponding to the "happiness emotional brain state" of the healthy participant. The training (4 training sessions over 2 weeks) was carried out using the rt-fMRI NF system guided by the brain-state classifier we had created. Thus, the informative voxels previously obtained in the first step, using SVM classification and Effect Mapping, were used to classify the Blood-Oxygen-Level Dependent (BOLD) activity of the patients and converted into real-time visual feedback during the neurofeedback training runs. Improvements in the classifier accuracy toward the end of the training were observed in all the patients [Session 4-1 Median = 6.563%; Range = 4.10-27.34; Wilcoxon Test (0), 2-tailed p = 0.031]. Clinical improvement also was observed in a blind standardized clinical evaluation [HDRS CE2-1 Median = 7; Range 2 to 15; Wilcoxon Test (0), 2-tailed p = 0.016], and in self-report assessments [BDI-II CE2-1 Median = 8; Range 1-15; Wilcoxon Test (0), 2-tailed p = 0.031]. In addition, the clinical improvement was still present 10 days after the intervention [BDI-II CE3-2_Median = 0; Range -1 to 2; Wilcoxon Test (0), 2-tailed p = 0.50/ HDRS CE3-2 Median = 0; Range -1 to 2; Wilcoxon Test (0), 2-tailed p = 0.625]. Although the number of participants needs to be increased and a control group included to confirm these findings, the results suggest a novel option for neural modulation and clinical alleviation in depression using noninvasive stimulation technologies.

Cultivating photosynthetic microorganisms in cooling water waste and urban effluents as a strategy of water regeneration and valorization.

Contaminants from cooling water waste (CWW) generated by industries represent an environmental hazard if discharged into aquatic bodies and soil without treatment. Most treatment strategies are energy-demanding and costly; hence, low-cost and sustainable treatment alternative technologies are needed. The present study proposed cyanobacteria culture as a low-cost biological method to treat cooling water waste (CWW) while simultaneously producing carbohydrates. For this purpose, CWW from a cooling tower was evaluated in different dilutions with domestic wastewater (DW) (DW25% -CWW75%, DW50% -CWW50%, DW25% -CWW75%, DW100%, and CWW100%) (v/v). The CWW provided a high content of inorganic carbon and low content of N and P, which resulted in a high C/N ratio promoting a fast carbohydrate accumulation but low biomass production. In contrast, cultures with higher DW concentrations achieved similar results in 14 days. The best results were obtained with DW25% -CWW75%, achieving up to 52 ± 18% carbohydrate content on day 8, with the highest biomass concentration of 1.7 ± 0.12 g L-1 on day 14. This culture removed >94% of TAN, N-NO3- and P-PO43-, and 84 ± 10.82% of COD. This strategy could be a promising approach to treating CWW and DW from the same industry and producing value-added products and bioenergy.

Correlation of the DNA Concentration of Human Samples to Electrical Bioimpedance Measurements: A Pilot Study.

It is necessary to evaluate the total deoxyribonucleic acid (DNA) concentration in gene expression assays. The existing techniques require equipment that is expensive for many labs in developing countries. Portable and inexpensive equipment is needed for easy and economical DNA quantification. Electrical bioimpedance spectroscopy (EBiS) is a non-invasive and inexpensive technique for examining the electrical properties of biological materials. The aim of this study was to explore a potential correlation between the measurement of total DNA extracted from human samples by UV-Vis spectrophotometry and EBiS. Hence, after quantifying the total DNA extracted from each sample by UV-Vis spectroscopy, EBiS was recorded and a possible correlation between the two measurements was analyzed. Considering the bioimpedance phase parameter at 5.24 MHz, a significant correlation was found with total DNA, especially when the concentration was below 100 ng/µL (Spearman coefficient = 0.82, p<0.005). Additional experiments are warranted to confirm these findings.

Carcinoid Heart Disease From a Primary Liver Carcinoid Tumor.

Carcinoid heart disease (CaHD) is part of the carcinoid syndrome. Cardiac involvement is present in 20% to 60% of patients with carcinoid syndrome and is normally from liver metastasis. We report the case of a patient who presented with CaHD disease with an undiagnosed primary tumor or a possible primary liver carcinoid tumor. (Level of Difficulty: Advanced.).

Calcified bodies in New World cutaneous leishmaniasis.

We report a case of a 9-year-old boy who presented with 2 lesions that were compatible clinically with cutaneous leishmaniasis of the New World. A skin biopsy showed tuberculoid granulomas with rounded calcified bodies. The diagnosis was supported by a positive leishmanin test and a positive polymerase chain reaction. The patient responded to specific treatment for leishmaniasis. These calcified bodies, described under different names in the literature (Michaelis-Gutmann bodies, Schaumann bodies, psammoma bodies, or conchoidal bodies), have been reported in an experimental leishmaniasis and, only once before, in a case of human leishmaniasis of the Old World.

Long-term semi-continuous production of carbohydrate-enriched microalgae biomass cultivated in low-loaded domestic wastewater.

The production of carbohydrate-enriched biomass from waste streams as a sustainable biofuel precursor is a noteworthy endeavor. This study investigates the long-term microalgae cultivated under low domestic wastewater loads and different hydraulic retention times (HRT) in a semi-continuous photobioreactor. The influence of operational conditions, the microalgae interaction with carbon, nutrients availability, and microbial population in terms of carbohydrate content were elucidated. The results revealed that the operation at similar low nutrients and carbon loads maintained at three different hydraulic retention times (HRT) of 10, 8, and 6 days caused different patterns in nutrients uptake and biomass composition. Particularly, the carbohydrate accumulation was greatly influenced by the unbalance in the N:P ratios than complete depletion of the nutrients. Hence, during the period operated at HRT of 10 d, high nutrients removal efficiencies were observed while gradually increasing carbohydrate content up to 57% in dry cell weight (DCW). Afterward, the decrease to 8 and 6 d of HRT showed lower nutrient consumption with depleted alkalinity, reaching an appreciably high carbohydrate accumulation of up to 46%, and 56%, respectively. The biomass concentration decreased in the order of HRT of 10, 8, and 6 days. This study demonstrated that microalgae adapted to low carbon and nutrient loads could still accumulate high carbohydrate at shorter HRT using domestic wastewater as substrate.

Factors associated with fluoxetine and norfluoxetine plasma concentrations and clinical response in Mexican patients with mental disorders.

Over the last few years, fluoxetine has been one of the most prescribed medications for the treatment of diverse psychiatric conditions in Mexico. Fluoxetine therapeutic effect is consequence of the joint action of the parent drug and its active metabolite, norfluoxetine. However, the clinical efficacy of fluoxetine, can be affected due to diverse factors, such as drug-drug interactions and the large interindividual variability in the pharmacokinetics of this drug. The aim of this study was to determine the factors associated with variability in plasma concentrations of fluoxetine and norfluoxetine and its association with the therapeutic response. Fluoxetine and norfluoxetine plasma concentrations were quantified by liquid chromatography in 81 Mexican patients with mental disorders; 25% of the patients had no medication adherence and 40% were below the reference range of fluoxetine plus norfluoxetine plasma concentrations. The results showed that concentrations can be affected by fluoxetine metabolism caused by CYP2D6 phenotype and the concomitant administration of olanzapine. Furthermore, CYP3A5 and CYP2C19 phenotype were associated with lower anxiety and depression control during treatment with fluoxetine. This study can be a starting point to elucidate the causes of fluoxetine variable response in Mexican patients with mental disorders, as well as to detect and support medication adherence.