Influence of visceral adiposity on cardiovascular risk in patients with systemic sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease characterized by systemic inflammation, endothelial dysfunction, generalized fibrosis and high cardiovascular mortality. The evaluation of cardiovascular risk through the visceral adiposity index (VAI) has been helpful due to its direct relationship to the body and visceral fat percentage. We evaluated the influence of body composition and anthropometrics on cardiovascular risk as measured by VAI in healthy controls (HC) and SSc. An analytical cross-sectional study of 66 participants (33 SSc and 33 HC), mean age 52.7 ± 10, 95% women, was conducted from August 2020 to January 2021. Inclusion criteria in cases were consecutive patients with SSc (ACR/EULAR 2013), 63.6% were diffuse cutaneous (dcSS) subtype, and 36.4 were limited cutaneous (lcSS) subtype. HC was matched by age and gender. Serum lipid profiles and InBody anthropometrics were analyzed and compared. We performed descriptive statistics, bivariate analysis with Student's t, or Mann-Whitney U, correlation and chi-square according to the variable type and distribution. Total cholesterol was significantly higher in SSc than HC (345 vs 194, p = < 0.001). The BMI was higher in HC (26.2 vs 28.9, p < 0.001). Kilograms of muscle (19.8 vs 28.9, p < 0.001) and total fat (23.4 vs 28.9, p < 0.001) were lower in SSc patients compared to HC. VAI was similar when BMI < 25, but significantly higher when BMI > 25 in SSc than in HC (3 vs 1.9, p = 0.030). The increase in BMI at overweight or obese in SSc is associated with a significant increase in cardiovascular risk.

Heart transplantation at the Peruvian National Heart Institute: One-decade single-center experience.

BACKGROUND: Heart transplantations are ideal for most patients with end-stage heart failure refractory to medical treatment. The transplantation program at the Peruvian National Heart Institute started with a 10-year continuity in 2010. OBJECTIVE: To compare our 10-year heart transplantation experience results with international standards and reflect on our Transplant Program. METHODS: We studied 83 patients who underwent orthotopic heart transplantation at a single center between January 2010 and December 2019. The recipients' profiles and survival rates were analyzed according to sex and age group, ensuring the information's confidentiality. RESULTS: The recipients' mean age was 41.2 ± 17 years, 88% were adults, and 68.7% were male. The main indications for transplantation were idiopathic dilated cardiomyopathy. 85.5% of recipients were clinically categorized as INTERMACS profiles 1-3 before transplantation. There was a significant difference between sexes regarding the preoperative left ventricular ejection fraction and between age groups regarding the waiting time. The average ischemia time was 3.1 h, operating time was 6.1 h, cardiopulmonary bypass time was 3 h, and aortic cross-clamp time was 1.7 h. The principal early postoperative complications were hematological disorders and acute kidney failure. The principal late ones were kidney failure and severe anemia. The postoperative mortality was 15.9%, and the principal causes were infection and then acute rejection. The survival at 1, 5, and 10 years was 87.5%, 79.8%, and 79.8%, respectively. The survival results were not influenced by sex or age group. CONCLUSION: Our patients' postoperative complications, mortality, and survival rates coincided with those reported by the ISHLT registry.

Percutaneous endovascular management of ascending aortic pseudoaneurysm after heart transplantation in a pediatric patient.

Ascending aortic pseudoaneurysm is a rare complication after HT. Surgery is the most conventional management, but in some patients, it is risky. We report the case of a ten-year-old child who underwent HT and developed an ascending aortic pseudoaneurysm in the aortic anastomosis. He was successfully treated with two covered stents through endovascular management. Endovascular therapy is an alternative management in high-risk patients. To our knowledge, this is the first report about endovascular therapy of an AAP after HT in a pediatric patient.

Brigatinib in ALK-positive non-small cell lung cancer: real-world data in the Latin American population (Bri-world extend CLICaP).

Background: Brigatinib has demonstrated its efficacy as first-line therapy and in further lines for ALK-positive non-small cell lung cancer (NSCLC) patients; however, real-world data in Latin America are scarce. Methods: From January 2018 to March 2020, 46 patients with advanced ALK-positive NSCLC received brigatinib as second or further line of therapy in Mexico and Colombia. The primary end point was progression-free survival (PFS); secondary end point was time to treatment discontinuation (TTD). Results: At a median follow-up of 9.3 months, the median PFS was 15.2 months (95% CI: 11.6-18.8), and TTD was 18.46 months (95% CI: 9.54-27.38). The estimated overall survival at 12 months was 80%. Safety profile was consistent with previously published data. Conclusion: Brigatinib is an effective treatment for previously treated ALK-positive NSCLC patients in a real-world setting.

Can the SARS-CoV-2 infection trigger systemic lupus erythematosus? A case-based review.

Systemic lupus erythematosus (SLE) is an autoimmune and multisystemic chronic inflammatory disease that can affect various organs, including skin, joints, kidneys, lungs and the nervous system. Infectious agents have long been implicated in the pathogenesis of SLE. The new viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shown that, in genetically predisposed patients could trigger the presentation or exacerbation of the autoimmune disease. We herein report a case of a 45-year-old man who presented respiratory symptoms, bilateral pleural effusion, ascites, splenomegaly, severe thrombocytopenia and renal failure with proteinuria and hematuria. SARS-CoV-2 PCR confirmed the COVID-19 diagnosis. We diagnosed the patient with SLE based on the clinical manifestations and positive immunological markers (2019 European League Against Rheumatism/American College of Rheumatology, score of 18). Glucocorticoid pulses were administered to the patient, which improved renal function. However, thrombocytopenia was also refractory to IV immunoglobulin and rituximab, so the patient underwent splenectomy. Through a systematic search of the medical literature, we retrieved two cases with newly onset SLE and five cases with previous SLE diagnosis that showed activity of the disease due to SARS-CoV-2 infection. We herein present a systemic review of these cases and discuss the clinical manifestations that could help to the diagnosis of this clinical condition.

Molecular weight distribution of the recalcitrant organic matter contained in kraft mill effluents and the identification of microbial consortia responsible for an anaerobic biodegradable fraction.

The objective of this research was to evaluate the distribution of the molecular weights of the recalcitrant organic matter contained in kraft mill effluents and identify microbial consortia responsible for an anaerobic biodegradable fraction. As a result, the average removal efficiencies of chemical organic demand (COD) and biological oxygen demand (BOD5) during the entire period of operation were 28% and 53%, respectively. The non-biodegradable organic matter was detected at molecular weights less than 1000 Da. However, most of the organic matter was in the molecular weight fraction higher than 10000 Da with 32 ± 11.6% COD as well as color (42.3 ± 8.7%), total phenolic compounds (35.9 ± 7.9%) and adsorbable organic compounds (AOX) (13.0 ± 2.7%). Methanogenic acetoclastic archaea of the genera Methanomethylovorans and Methanosarcina were found in the surface and middle zones of the reactor. Moreover, Methanosaeta and Methanolinea were identified in the low zone of the reactor. In all zones of the reactor, Desulfomicrobium and Desulfovibrio were found to be the most dominant genera of sulfate-reducing bacteria (SRB).

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.

The VEGFA -1154G/A polymorphism is associated with reduced risk of rheumatoid arthritis but not with systemic lupus erythematosus in Mexican women.

BACKGROUND: Levels of circulating vascular endothelial growth factor (VEGF) (a potent endothelial-cell-specific angiogenic factor) have been correlated with disease activity in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). In addition, several single nucleotide polymorphisms (SNPs), including the VEGFA -2578C/A, have been associated with RA in some populations. By contrast, the role of different VEGFA SNPs in the susceptibility to SLE has received little attention. Thus, the present study aimed to determine whether the VEGFA -2578C/A, -1154G/A and -634G/C polymorphisms confer risk or were associated with reduced risk of RA or SLE in a Mexican population. METHODS: The present study included 903 women from Mexico: 405 were patients with RA, 282 had SLE and 216 were healthy individuals. The genotypes were obtained with TaqMan probes. RESULTS: The data obtained in the present study suggest that the VEGFA -2578C/A and -634G/C polymorphisms are not risk factors for RA or SLE; however, VEGFA -1154G/A was associated with reduced risk in women with RA (odds ratio = 0.6, pc  = 0.0051) but not with SLE (odds ratio = 0.7, pc  = 0.13). CONCLUSIONS: The present study is the first to document an association between VEGFA -1154G/A and reduced risk in women with RA but not with SLE.

Black mamba venom peptides target acid-sensing ion channels to abolish pain.

Polypeptide toxins have played a central part in understanding physiological and physiopathological functions of ion channels. In the field of pain, they led to important advances in basic research and even to clinical applications. Acid-sensing ion channels (ASICs) are generally considered principal players in the pain pathway, including in humans. A snake toxin activating peripheral ASICs in nociceptive neurons has been recently shown to evoke pain. Here we show that a new class of three-finger peptides from another snake, the black mamba, is able to abolish pain through inhibition of ASICs expressed either in central or peripheral neurons. These peptides, which we call mambalgins, are not toxic in mice but show a potent analgesic effect upon central and peripheral injection that can be as strong as morphine. This effect is, however, resistant to naloxone, and mambalgins cause much less tolerance than morphine and no respiratory distress. Pharmacological inhibition by mambalgins combined with the use of knockdown and knockout animals indicates that blockade of heteromeric channels made of ASIC1a and ASIC2a subunits in central neurons and of ASIC1b-containing channels in nociceptors is involved in the analgesic effect of mambalgins. These findings identify new potential therapeutic targets for pain and introduce natural peptides that block them to produce a potent analgesia.

Mambalgin-1 Pain-relieving Peptide, Stepwise Solid-phase Synthesis, Crystal Structure, and Functional Domain for Acid-sensing Ion Channel 1a Inhibition.

Mambalgins are peptides isolated from mamba venom that specifically inhibit a set of acid-sensing ion channels (ASICs) to relieve pain. We show here the first full stepwise solid phase peptide synthesis of mambalgin-1 and confirm the biological activity of the synthetic toxin both in vitro and in vivo. We also report the determination of its three-dimensional crystal structure showing differences with previously described NMR structures. Finally, the functional domain by which the toxin inhibits ASIC1a channels was identified in its loop II and more precisely in the face containing Phe-27, Leu-32, and Leu-34 residues. Moreover, proximity between Leu-32 in mambalgin-1 and Phe-350 in rASIC1a was proposed from double mutant cycle analysis. These data provide information on the structure and on the pharmacophore for ASIC channel inhibition by mambalgins that could have therapeutic value against pain and probably other neurological disorders.

Binding site and inhibitory mechanism of the mambalgin-2 pain-relieving peptide on acid-sensing ion channel 1a.

Acid-sensing ion channels (ASICs) are neuronal proton-gated cation channels associated with nociception, fear, depression, seizure, and neuronal degeneration, suggesting roles in pain and neurological and psychiatric disorders. We have recently discovered black mamba venom peptides called mambalgin-1 and mambalgin-2, which are new three-finger toxins that specifically inhibit with the same pharmacological profile ASIC channels to exert strong analgesic effects in vivo. We now combined bioinformatics and functional approaches to uncover the molecular mechanism of channel inhibition by the mambalgin-2 pain-relieving peptide. Mambalgin-2 binds mainly in a region of ASIC1a involving the upper part of the thumb domain (residues Asp-349 and Phe-350), the palm domain of an adjacent subunit, and the ß-ball domain (residues Arg-190, Asp-258, and Gln-259). This region overlaps with the acidic pocket (pH sensor) of the channel. The peptide exerts both stimulatory and inhibitory effects on ASIC1a, and we propose a model where mambalgin-2 traps the channel in a closed conformation by precluding the conformational change of the palm and ß-ball domains that follows proton activation. These data help to understand inhibition by mambalgins and provide clues for the development of new optimized blockers of ASIC channels.

Human ASIC3 channel dynamically adapts its activity to sense the extracellular pH in both acidic and alkaline directions.

In rodent sensory neurons, acid-sensing ion channel 3 (ASIC3) has recently emerged as a particularly important sensor of nonadaptive pain associated with tissue acidosis. However, little is known about the human ASIC3 channel, which includes three splice variants differing in their C-terminal domain (hASIC3a, hASIC3b, and hASIC3c). hASIC3a transcripts represent the main mRNAs expressed in both peripheral and central neuronal tissues (dorsal root ganglia [DRG], spinal cord, and brain), where a small proportion of hASIC3c transcripts is also detected. We show that hASIC3 channels (hASIC3a, hASIC3b, or hASIC3c) are able to directly sense extracellular pH changes not only during acidification (up to pH 5.0), but also during alkalization (up to pH 8.0), an original and inducible property yet unknown. When the external pH decreases, hASIC3 display a transient acid mode with brief activation that is relevant to the classical ASIC currents, as previously described. On the other hand, an external pH increase activates a sustained alkaline mode leading to a constitutive activity at resting pH. Both modes are inhibited by the APETx2 toxin, an ASIC3-type channel inhibitor. The alkaline sensitivity of hASIC3 is an intrinsic property of the channel, which is supported by the extracellular loop and involves two arginines (R68 and R83) only present in the human clone. hASIC3 is thus able to sense the extracellular pH in both directions and therefore to dynamically adapt its activity between pH 5.0 and 8.0, a property likely to participate in the fine tuning of neuronal membrane potential and to neuron sensitization in various pH environments.

Real-time inference in communication across cultures: Evidence from a nonindustrialized society.

In everyday communication, speakers and listeners make sophisticated inferences about their conversation partner's intended meaning. They combine their knowledge of the visuospatial context with reasoning about the other person's knowledge state and rely on shared assumptions about how language is used to express communicative intentions. However, these assumptions may differ between languages of nonindustrialized-where conversations often primarily take place within a, so-called, society of intimates-and industrialized cultures-societies of strangers. Here, we study inference in communication in the Tsimane', an indigenous people of the Bolivian Amazon, who have little contact with industrialization or formal education. Using a referential communication task, we probe how Tsimane' speakers refer to objects in the world around them when there are potential ambiguities (e.g., referring to a cup when there are multiple cups in view) across different visual contexts. Using an eye-tracking task, we probe the real-time inferences that Tsimane' listeners make about the speaker's intentions. We find that Tsimane' speakers use visual (color, size) contrasts to disambiguate referents (e.g., "Hand me the small cup"), much like English speakers, and they predictively direct their gaze to objects in a contrast set when they hear a modifier (e.g., "small"). Despite myriad cultural and linguistic dissimilarities between the two populations, the qualitative patterns of behavior and eye-gaze of Tsimane' and English speakers were strikingly similar, suggesting that the communicative expectations underlying many everyday inferences may be shared across cultures. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

[Prevalence of persistent hypogammaglobulinemia in patients with autoimmune rheumatic disease who received treatment with Rituximab in a national medical center in Mexico]. / Prevalencia de hipogammaglobulinemia persistente en pacientes con enfermedad autoinmune que reciben rituximab en un centro de referencia nacional en México.

OBJECTIVE: To describe the prevalence of persistent hypogammaglobulinemia in patients receiving Rituximab as a treatment for autoimmune rheumatological diseases. METHODS: A transversal, retrospective and unicentric study, carried out in patients with autoimmune rheumatic diseases who were admitted to the Rheumatology service of the Hospital de Especialidades Dr. Antonio Fraga Mouret, Centro Médico Nacional La Raza, Mexico City, to receive treatment with rituximab between January 2013 and January 2018. Descriptive and inferential statistics of serum levels of immunoglobulins, clinical-demographic characteristics, diagnosis, and treatment received were performed. RESULTS: from 262 patients with autoimmune rheumatological disease who received treatment with Rituximab; We identified 8 patients with persistent hypogammaglobulinemia (6 women and 2 men), this is a prevalence of 3.1%. No associated factors with the development of hypogammaglobulinemia were identified. CONCLUSIONS: Until now, no associated prognostic or predictive factors have been identified with persistent hypogammaglobulinemia. Additional prospective studies are required to understand more precisely the implications of persistent hypogammaglobulinemia in patients with autoimmune diseases.

OBJECTIVO: Determinar la prevalencia de hipogammaglobulinemia persistente en pacientes con enfermedades reumatológicas autoinmunes que reciben rituximab. MÉTODOS: Estudio trasversal, retrospectivo y unicéntrico, emprendido en pacientes con enfermedades reumatológicas autoinmunes, que acudieron a la Consulta externa del servicio de Reumatología del Hospital de Especialidades Dr. Antonio Fraga Mouret, Centro Médico Nacional La Raza, Ciudad de México, entre enero de 2013 y enero de 2018, para recibir tratamiento con rituximab. El análisis de los datos se efectuó con estadística descriptiva e inferencial, para la evaluación de las concentraciones séricas de inmunoglobulinas, características clínico demográficas, diagnóstico y tratamiento. RESULTADOS: Estudio trasversal, retrospectivo y unicéntrico, emprendido en pacientes con enfermedades reumatológicas autoinmunes, que acudieron a la Consulta externa del servicio de Reumatología del Hospital de Especialidades Dr. Antonio Fraga Mouret, Centro Médico Nacional La Raza, Ciudad de México, entre enero de 2013 y enero de 2018, para recibir tratamiento con rituximab. El análisis de los datos se efectuó con estadística descriptiva e inferencial, para la evaluación de las concentraciones séricas de inmunoglobulinas, características clínico demográficas, diagnóstico y tratamiento. CONCLUSIONES: Hasta el momento no se han identificado factores asociados, pronósticos o predictivos, con hipogammaglobulinemia persistente. Se requieren estudios prospectivos adicionales para conocer con mayor precisión las implicaciones de la hipogammaglobulinemia persistente en pacientes con enfermedades autoinmunes.

Mechanisms of Action of the Peptide Toxins Targeting Human and Rodent Acid-Sensing Ion Channels and Relevance to Their In Vivo Analgesic Effects.

Acid-sensing ion channels (ASICs) are voltage-independent H+-gated cation channels largely expressed in the nervous system of rodents and humans. At least six isoforms (ASIC1a, 1b, 2a, 2b, 3 and 4) associate into homotrimers or heterotrimers to form functional channels with highly pH-dependent gating properties. This review provides an update on the pharmacological profiles of animal peptide toxins targeting ASICs, including PcTx1 from tarantula and related spider toxins, APETx2 and APETx-like peptides from sea anemone, and mambalgin from snake, as well as the dimeric protein snake toxin MitTx that have all been instrumental to understanding the structure and the pH-dependent gating of rodent and human cloned ASICs and to study the physiological and pathological roles of native ASICs in vitro and in vivo. ASICs are expressed all along the pain pathways and the pharmacological data clearly support a role for these channels in pain. ASIC-targeting peptide toxins interfere with ASIC gating by complex and pH-dependent mechanisms sometimes leading to opposite effects. However, these dual pH-dependent effects of ASIC-inhibiting toxins (PcTx1, mambalgin and APETx2) are fully compatible with, and even support, their analgesic effects in vivo, both in the central and the peripheral nervous system, as well as potential effects in humans.

Mambalgin-1 pain-relieving peptide locks the hinge between α4 and α5 helices to inhibit rat acid-sensing ion channel 1a.

Acid-sensing ion channels (ASICs) are proton-gated cationic channels involved in pain and other processes, underscoring the potential therapeutic value of specific inhibitors such as the three-finger toxin mambalgin-1 (Mamb-1) from snake venom. A low-resolution structure of the human-ASIC1a/Mamb-1 complex obtained by cryo-electron microscopy has been recently reported, implementing the structure of the chicken-ASIC1/Mamb-1 complex previously published. Here we combine structure-activity relationship of both the rat ASIC1a channel and the Mamb-1 toxin with a molecular dynamics simulation to obtain a detailed picture at the level of side-chain interactions of the binding of Mamb-1 on rat ASIC1a channels and of its inhibition mechanism. Fingers I and II of Mamb-1 but not the core of the toxin are required for interaction with the thumb domain of ASIC1a, and Lys-8 of finger I potentially interacts with Tyr-358 in the thumb domain. Mamb-1 does not interfere directly with the pH sensor as previously suggested, but locks by several contacts a key hinge between α4 and α5 helices in the thumb domain of ASIC1a to prevent channel opening. Our results provide an improved model of inhibition of mammalian ASIC1a channels by Mamb-1 and clues for further development of optimized ASIC blockers.

Structural elements for the generation of sustained currents by the acid pain sensor ASIC3.

ASIC3 is an acid-sensing ion channel expressed in sensory neurons, where it participates in acidic and inflammatory pain. In addition to the "classical" transient current, ASIC3 generates a sustained current essential for pain perception. Using chimeras between the ASIC3 and ASIC1a channels we show that the first transmembrane domain (TM1), combined with the N-terminal domain, is the key structural element generating the low pH (<6.5)-evoked sustained current. The TM1 domain also modulates the pH-dependent activation of the fast transient current thus contributing to a constitutive window current, another type of sustained current present near physiological pH. The C-terminal and the TM2 domains negatively regulate both types of sustained current, and the extracellular loop affects its kinetics. These data provide new information to aid understanding the mechanisms of the multifaceted pH gating of ASIC3. Together with the peak current, both components of the sustained current (window and sustained at pH <6.5) allow ASIC3 to adapt its behavior to a wide range of extracellular pH variations by generating transient and/or sustained responses that contribute to nociceptor excitability.

Locoregional control and toxicity after pleurectomy/decortication and intensity-modulated pleural radiation therapy in patients with malignant pleural mesothelioma.

BACKGROUND: Treatment of malignant pleural mesothelioma (MPM) represents a major challenge for oncologists. Multimodality treatment, which generally involves induction chemotherapy, surgery and radiotherapy have recently shown promising results. The aim of this study was to evaluate the locoregional control and toxicity of intensity modulated radiotherapy (IMRT) after pleurectomy and decortication (P/D) as part of trimodality therapy for patients with locally advanced MPM. METHODS: We prospectively analyzed data from 20 patients with MPM treated at a single tertiary-care institution. Initially every patient received induction chemotherapy with platinum-based chemotherapy. After chemotherapy, patients without progression underwent P/D, and if feasible, hemi-thoracic IMRT was administered at a planned dose of 50.4-54 Gy in 28-30 fractions and treated with 9-11 noncoplanar fields. RESULTS: A total of 15 of the 20 enrolled patients underwent P/D followed by IMRT to the hemi-thoracic cavity. The median total radiotherapy dose was 48.7 Gy (23.4-54 Gy). Radiation pneumonitis (RP) developed in nine patients (60%), and of these, two patients (13.3%) experienced G3 or G4 RP. The estimated locoregional-relapse-free survival at two years was 75.9%, and the main pattern of recurrence was distant (72.7%). For the entire cohort median follow-up was 22.7 months, median progression-free survival was 18.9 months and median overall survival 23.6 months. CONCLUSIONS: Platinum-based chemotherapy followed by lung-sparing surgery (P/D) and IMRT is a feasible and safe treatment modality that yields acceptable locoregional control in patients with locally advanced MPM; however, these results should be corroborated in larger studies.

Probiotics' effectiveness on symptoms, histological features and feeding tolerance in ulcerative colitis / Efectividad de probióticos sobre síntomas, histología y tolerancia alimentaria en colitis ulcerativa

Background: Probiotics have been used in the adjuvant treatment of Ulcerative Colitis (UC). Objective: To evaluate the role of a combination of probiotics on the clinical, histological changes and feeding tolerance in patients with UC. Methods: An open UC patients with mild to moderate activity and clinical trial was conducted. Patients were randomized to receive or a combination of 6 strains of probiotics for 3 months while continuing their drug treatment established. UC activity was assessed by Truelove and Witts scale and histological findings by Gupta index. Descriptive statistics, Chi square test and Student t test for comparison of the two groups was performed. Results: In each group 17 patients were included. An improvement was found in the disease activity (52.9% vs. 23.5%, p = 0.07) and in histologic index (82.3% vs. 41.1%, p = 0.03) in patients treated with probiotics compared to the control group. Improved food tolerance was also observed in patients treated with probiotics. Conclusion: The study shows a beneficial short-term effect on symptoms, histological findings and feeding tolerance with the administration of a combination of 6 strains of probiotics in patients with UC.

Introducción: los probióticos han sido utilizados en el tratamiento adyuvante de la colitis ulcerativa (CU). Objetivo: evaluar el papel de una combinación de probióticos sobre las manifestaciones clínicas, cambios histológicos y tolerancia alimentaria en pacientes con CU. Métodos: se realizó un ensayo clínico abierto de pacientes con CU y actividad leve a moderada. Los pacientes se aleatorizaron para recibir, o no, una combinación de 6 cepas de probióticos durante 3 meses, mientras continuaban con el tratamiento farmacológico establecido. Se evaluó la actividad de la CU mediante la escala de Truelove and Witts, y los hallazgos histológicos mediante el índice de Gupta. Se realizó estadística descriptiva, prueba de Chi cuadrada y t de Student para la comparación de ambos grupos. Resultados: se incluyeron 17 pacientes por grupo. Se encontró una mejoría en la actividad de la enfermedad (52.9% frente a 23.5%, p = 0.07) y en el índice histológico (82.3% frente a 41.1%, p = 0.03) en los pacientes tratados con probióticos en comparación con el grupo control. También se observó una mejor tolerancia alimentaria en los pacientes tratados con probióticos. Conclusión: el estudio muestra un efecto benéfico a corto plazo sobre los síntomas, hallazgos histológicos y tolerancia alimentaria con la administración de una combinación de 6 cepas de probióticos en pacientes con CU.

Pharmacological modulation of Acid-Sensing Ion Channels 1a and 3 by amiloride and 2-guanidine-4-methylquinazoline (GMQ).

Acid-Sensing Ion Channels (ASICs) are cation channels activated by extracellular acidification that emerge as potential pharmacological targets in pain and other neurological disorders. Here, we compare the pharmacological modulation of ASIC1a and ASIC3 channels by amiloride and 2-guanidine-4-methylquinazoline (GMQ), two compounds commonly used for their in vitro and in vivo investigation. We analyzed the effect of amiloride on the pH-dependent activation and inactivation, the relative influence of the extracellular domain and the transmembrane/cytosolic domains on the effect of amiloride and GMQ using chimeras between ASIC1a and ASIC3, and how these compounds potentiate the physiologically relevant ASIC3 sustained window current. We showed that amiloride and GMQ shift the pH-dependent activation and inactivation in the same directions, which depend on the channel, and that their effects rely on the nature of the extracellular domain but can be indirectly modulated in their amplitude by the transmembrane/cytosolic domains. The extracellular domain explains the pharmacological potentiating effect of amiloride and GMQ on the window current in ASIC3, and why these compounds failed to generate a window current in ASIC1a. Amiloride and GMQ have similar and purely additive effects suggesting that they act through a common unique binding site different from acidic pockets. Finally, a simple cycle analysis using GMQ that targets the nonproton ligand-sensor, and two peptide inhibitors of ASIC1a targeting the acidic pockets (PcTx1 and mambalgin-1), shows overlap between the mechanisms by which GMQ and PcTx1 modify inactivation and suggests shared mechanisms of regulation of the pH-dependent inactivation of ASIC1a between these two regions.