Gadoxetic Acid in MRI: A Five-Year Experience at a High-Complexity Hospital in Colombia.

Objective The objective of the study was to evaluate the use of the hepatospecific contrast agent, gadoxetic acid, for MRI in patients at a high-complexity hospital in Medellin, Colombia, from 2016 to 2022. Materials and methods This was an observational, descriptive, and retrospective cross-sectional study involving patients who had undergone MRI with gadoxetic acid from February 2016 to January 2022. The MRI studies were interpreted by two radiologists specializing in body imaging, each with at least 10 years of experience. The medical records of the identified patients were reviewed. Quantitative variables were presented using either means and standard deviations or medians and interquartile ranges, depending on the distribution of the variables. Qualitative variables were represented through absolute and relative frequencies. Results A total of 100 pharmacy records were collected, leading to a final sample of 75 patients aged between three and 91 years. The primary reason for imaging was to assess focal liver lesions in 58 patients (77.3%), with bile duct injury being the second most common indication in 16 patients (21.3%). A diagnostic alteration was noted in 69.3% of cases (52 patients). Among the 58 focal liver lesions analyzed using a hepatospecific agent, 31 cases (53.4%) were diagnosed as focal nodular hyperplasia. Conclusion Our study reinforces the clinical value of gadoxetic acid-enhanced MRI in refining diagnostic assessments, particularly in cases involving bile duct and focal hepatic lesions.

Ghrelin enhances tubular magnesium absorption in the kidney.

Osteoporosis after bariatric surgery is an increasing health concern as the rate of bariatric surgery has risen. In animal studies mimicking bariatric procedures, bone disease, together with decreased serum levels of Ca2+, Mg2+ and the gastric hormone Ghrelin were described. Ghrelin regulates metabolism by binding to and activating the growth hormone secretagogue receptor (GHSR) which is also expressed in the kidney. As calcium and magnesium are key components of bone, we tested the hypothesis that Ghrelin-deficiency contributes to osteoporosis via reduced upregulation of the renal calcium channel TRPV5 and the heteromeric magnesium channel TRPM6/7. We expressed GHSR with TRPV5 or TRPM6/7 channel in HEK293 cells and treated them with purified Ghrelin. Whole-cell current density was analyzed by patch-clamp recording. Nephron-specific gene expression was performed by tubular microdissection followed by qPCR in wild-type (WT) mice, and immunofluorescent imaging of GHSR-eGFP mice. Tubular magnesium homeostasis was analyzed in GHSR-null and WT mice at baseline and after caloric restriction. After Ghrelin exposure, whole-cell current density did not change for TRPV5 but increased for TRPM6/7 in a dose-dependent fashion. Applying the Ghrelin-mimetic (D-Trp7, Ala8,D-Phe10)-α-MSH (6-11) amide without and with the GHSR antagonist (D-Lys3)-GHRP6, we confirmed the stimulatory role of Ghrelin towards TRPM6/7. As GHSR initiates downstream signaling via protein kinase A (PKA), we found that the PKA inhibitor H89 abrogated TRPM6/7 stimulation by Ghrelin. Similarly, transfected Gαs, but not the Gαs mutant Q227L, nor Gαi2, Gαq, or Gα13 upregulated TRPM6/7 current density. In microdissected TALs and DCTs similar levels of GHSR mRNA were detected. In contrast, TRPM6 mRNA was expressed in the DCT and also detected in the TAL at 25% expression compared to DCT. Immunofluorescent studies using reporter GHSR-eGFP mice showed a strong eGFP signal in the TAL but surprisingly displayed no eGFP signal in the DCT. In 3-, 6-, and 9-month-old GHSR-null and WT mice, baseline serum magnesium was not significantly different, but 24-h urinary magnesium excretion was elevated in 9-month-old GHSR-null mice. In calorically restricted GHSR-null mice, we detected excess urinary magnesium excretion and reduced serum magnesium levels compared to WT mice. The kidneys from calorically restricted WT mice showed upregulated gene expression of magnesiotropic genes Hnf1b, Cldn-16, Cldn-19, Fxyd-2b, and Parvalbumin compared to GHSR-null mice. Our in vitro studies show that Ghrelin stimulates TRPM6/7 via GHSR and Gαs-PKA signaling. The murine studies are consistent with Ghrelin-GHSR signaling inducing reduced urinary magnesium excretion, particularly in calorically restricted mice when Ghrelin levels are elevated. This effect may be mediated by Ghrelin-upregulation of TRPM6 in the TAL and/or upregulation of other magnesiotropic genes. We postulate that rising Ghrelin levels with hunger contribute to increased renal Mg2+ reabsorption to compensate for lack of enteral Mg2+ uptake.

Epidemiology, clinical features, and classification of 3,404 patients with uveitis: Colombian Uveitis Multicenter Study (COL-UVEA).

PURPOSE: To describe the epidemiology, clinical features, and classification of uveitis in a large cohort of Colombian patients. METHODS: Data were collected from seven ophthalmological referral centers in the four main cities in Colombia. The study included patients with a confirmed diagnosis of uveitis from January 2010 to December 2022. Information on demographics, ophthalmic examination findings, uveitis classification, and etiology was recorded. RESULTS: The study reviewed 3,404 clinical records of patients with uveitis. The mean age at diagnosis was 41.1 (SD 19.0) years, and 54.2% of the patients were female. Overall, 1,341(39.4%) were infectious, 626 (18.4%) non-infectious, and four masquerade syndromes (0.1%). The most common types of uveitis were unilateral (66.7%), acute (48.3%), and non-granulomatous (83%). Anterior uveitis was the most common anatomical localization (49.5%), followed by posterior uveitis (22.9%), panuveitis (22.3%), and intermediate uveitis (5.2%). A diagnosis was established in 3,252 (95.5%) cases; idiopathic was the most common cause (27.7%), followed by toxoplasmosis (25.3%) and virus-associated uveitis (6.4%). The age group between 30 and 50 exhibited the highest frequency of uveitis. CONCLUSION: This multicenter study comprehensively describes uveitis characteristics in Colombian patients, providing valuable insights into its demographic and clinical features. The study findings emphasize the need to continue updating the changing patterns of uveitis to improve diagnosis and treatment strategies for diseases associated with intraocular inflammation.

Clinical patterns and risk factors in scleritis: a multicentric study in Colombia.

PURPOSE: This study aims to describe the clinical characteristics of scleritis in a large cohort of Colombian patients and identify factors associated with the clinical presentation. METHODS: Retrospective case series of patients with scleritis from 2015 to 2020. Clinical records were obtained from seven uveitis referral centers in Colombia. Patients with a diagnosis of episcleritis were excluded. RESULTS: We evaluated 389 patients with scleritis (509 eyes). There was a female predominance (75.6%) with a mean age of 51 ± 15 years. Most cases were noninfectious (94.8%) and unilateral (69.2%). The most frequent type of inflammation was diffuse anterior scleritis (41.7%), followed by nodular scleritis (31.9%) and necrotizing scleritis (12.3%). Systemic autoimmune diseases were found in 41.3% of patients, the most common being rheumatoid arthritis (18.5%) and granulomatosis with polyangiitis (5.9%). Polyautoimmunity was found in 10.4% of those with a systemic autoimmune disease. The most frequent treatment was systemic steroids (50.9%), followed by systemic NSAIDs (32.4%). Steroid-sparing immunosuppression was required in 49.1% of patients. Systemic autoimmune diseases were more common in patients with necrotizing scleritis and those older than 40 years of age. Best-corrected visual acuity of 20/80 or worse at presentation was more common in necrotizing scleritis and subjects with associated uveitis, ocular hypertension, or who were over 40 years of age. CONCLUSIONS: This is the first study in Colombia and the largest in Latin America describing the clinical characteristics and presentation patterns of scleritis. The most common presentation was in females, with unilateral, anterior diffuse noninfectious scleritis. Systemic autoimmune diseases and polyautoimmunity were frequent, as was the need for steroid-sparing immunosuppression. Age over 40 and necrotizing scleritis were associated with higher odds of having a systemic autoimmune disease and worse visual acuity at presentation.

Graphene-Based Biosensors for Molecular Chronic Inflammatory Disease Biomarker Detection.

Chronic inflammatory diseases, such as cancer, diabetes mellitus, stroke, ischemic heart diseases, neurodegenerative conditions, and COVID-19 have had a high number of deaths worldwide in recent years. The accurate detection of the biomarkers for chronic inflammatory diseases can significantly improve diagnosis, as well as therapy and clinical care in patients. Graphene derivative materials (GDMs), such as pristine graphene (G), graphene oxide (GO), and reduced graphene oxide (rGO), have shown tremendous benefits for biosensing and in the development of novel biosensor devices. GDMs exhibit excellent chemical, electrical and mechanical properties, good biocompatibility, and the facility of surface modification for biomolecular recognition, opening new opportunities for simple, accurate, and sensitive detection of biomarkers. This review shows the recent advances, properties, and potentialities of GDMs for developing robust biosensors. We show the main electrochemical and optical-sensing methods based on GDMs, as well as their design and manufacture in order to integrate them into robust, wearable, remote, and smart biosensors devices. We also describe the current application of such methods and technologies for the biosensing of chronic disease biomarkers. We also describe the current application of such methods and technologies for the biosensing of chronic disease biomarkers with improved sensitivity, reaching limits of detection from the nano to atto range concentration.

Validity and reliability of a set of sexual stimuli in a sample of Colombian heterosexual young women / Validez y fiabilidad de un set de estímulos sexuales en una muestra de jóvenes mujeres heterosexuales colombianas

Vaginal photoplethysmography is a method for physiological evaluation of sexual arousal in women. This paper undertook to obtain the validity and reliability of a set of sexual stimuli in young heterosexual women. Six six-minute video clips were selected. A total of 34 women aged 18-30 years(M = 22.38, SD = 2.52) participated in this study. Objective Sexual Arousal, Subjective Sexual Arousal, emotional activation, emotional valence and socio-psycho-sexual information were evaluated. Three of the six sexual stimuli were selected from the scores obtained after the experimental phase. It was observed that the aforementioned video clips produced the most arousal-activation-pleasure, with internally consistent measures. As expected, good indicators of external validity were observed, with statistically significant differences. According to the data obtained, the pooled use of the three stimuli increases the like lihoodof obtainingan objective arousal response in healthy young women, there by minimizing the possibilities of displeasure.

La fotopletismografía vaginal es un método para evaluar fisiológicamente la excitación sexual objetiva en mujeres. El objetivo del presente estudio es obtener la validez y fiabilidad de un set de estímulos sexuales en mujeres jóvenes heterosexuales. Se seleccionaron seis videos sexuales de 6 minutos de duración. Un total de 34 mujeres entre los 18 y 30 años (M = 22.38; SD = 2.52) participaron en este estudio. Se evaluó la Excitación Sexual Objetiva, Subjetiva, la activación y valencia emocional e información sociopsicosexual. Tres de los seis estímulos sexuales se seleccionaron a partir de las puntuaciones obtenidas luego de la fase experimental. Se observó que estos fueron los que mayor excitación-activación-agrado produjeron con medidas internamente consistentes. Se observaron buenos indicadores de validez externa con diferencias estadísticamente significativas, como era de esperarse. Según los datos obtenidos, el uso agrupado de los tres estímulos aumentan la probabilidad de obtener unarespuesta de excitación objetiva en mujeres jóvenes saludables y minimizan las posibilidades de desagrado.

Predominant role of spinal P2Y1 receptors in the development of neuropathic pain in rats.

The role of P2X2/3, P2X3, P2X4 or P2X7 and P2Y2, P2Y6, and P2Y12 receptors in neuropathic pain has been widely studied. In contrast, the role of P2Y1 receptors is scarcely studied. In this study we assessed the role of P2Y1 receptors in several neuropathic pain models in the rat. Furthermore, we analyzed the expression of P2Y1 receptors in the ipsilateral dorsal root ganglia (DRG) and dorsal part of the spinal cord during the development and maintenance of neuropathic pain. We also determined the effect of the P2Y1 receptor antagonist on the expression of P2Y1 receptors. Chronic constriction injury (CCI), spared nerve injury (SNI) or spinal nerve ligation (SNL) produced tactile allodynia from 1 to 14 days after nerve injury. CCI, SNI and SNL enhanced expression of P2Y1 receptors in DRG but not in the dorsal part of the spinal cord at 1-3 days after injury. Intrathecal injection of the selective P2Y1 receptor antagonist MRS2500, but not vehicle, reduced tactile allodynia in rats 1-3 days after CCI, SNI, or SNL. Moreover, intrathecal injection of MRS2500 (at day 1 or 3) reduced neuropathy-induced up-regulation of P2Y1 receptors expression. Intrathecal injection of MRS2500 lost most of the antiallodynic effect when injected 14 days after injury. At this time, MRS2500 did not modify nerve-injury-induced P2Y1 receptors up-regulation. Our results suggest that P2Y1 receptors are localized in DRG, are up-regulated by nerve injury and play a pronociceptive role in development and, to a lesser extent, maintenance of neuropathic pain.

Role of spinal P2Y6 and P2Y11 receptors in neuropathic pain in rats: possible involvement of glial cells.

BACKGROUND: The participation of spinal P2X receptors in neuropathic pain is well recognized. However, the role of P2Y receptors has been less studied. The purpose of this study was to investigate the contribution of spinal P2Y6,11 receptors following peripheral nerve damage induced by spinal nerve ligation. In addition, we determined the expression of P2Y6,11 receptors in the dorsal spinal cord in presence of the selective P2Y6,11 receptors antagonists. Furthermore, we evaluated the participation of spinal microglia and astrocytes in the pronociceptive role of P2Y6,11 receptors. RESULTS: Spinal administration of the selective P2Y6 (MRS2578, 10-100 µM) and P2Y11 (NF340, 0.3-30 µM) receptor antagonists reduced tactile allodynia in spinal nerve ligated rats. Nerve injury increased the expression of P2Y6,11 receptors at 7, 14 and 21 days after injury. Furthermore, intrathecal administration of MRS2578 (100 µM/day) and NF340 (30 µM/day) for 3 days significantly reduced spinal nerve injury-induced increase in P2Y6,11 receptors expression, respectively. Spinal treatment (on day 14 after injury) with minocycline (100 µg/day) or fluorocitrate (1 nmol/day) for 7 days reduced tactile allodynia and spinal nerve injury-induced up-regulation in Iba-1 and GFAP, respectively. In addition, minocycline reduced nerve injury-induced up-regulation in P2Y6,11 receptors whereas that fluorocitrate diminished P2Y11, but not P2Y6, receptors up-regulation. Intrathecal treatment (on day 21 after injury) with the selective P2Y6 (PSB0474, 3-30 µM) and P2Y11 (NF546, 1-10 µM) receptor agonists produced remarkable tactile allodynia in nerve ligated rats previously treated with minocycline or fluorocitrate for 7 days. CONCLUSIONS: Our data suggest that spinal P2Y6 is present in spinal microglia while P2Y11 receptors are present in both spinal microglia and astrocytes, and both receptors are up-regulated in rats subjected to spinal nerve injury. In addition, our data suggest that the spinal P2Y6 and P2Y11 receptors participate in the maintenance of neuropathic pain.

Haplotipos del gen de la globina beta en portadores de hemoglobina S en Colombia / Beta globin haplotypes in hemoglobin S carriers in Colombia

Introducción. La mutación de la hemoglobina S (HbS) va acompañada por otras mutaciones en la región del cromosoma 11, conocida como conjunto de la globina beta(beta globin cluster). El patrón de combinación de estos polimorfismos da lugar a los haplotipos que se heredan junto con la mutación de la hemoglobina S, se denominan haplotipos de la mutación bs y revisten gran importancia epidemiológica y clínica. Objetivo. Determinar la frecuencia de los principales haplotipos asociados al gen HBB en pacientes colombianos heterocigotos para hemoglobina S. Materiales y métodos. En la Clínica Colsanitas se han estudiado a la fecha 1.200 muestras de sangre periférica de niños en busca de hemoglobinopatías, y se ha encontrado el rasgo falciforme como la hemoglobinopatía más frecuente. Se determinaron los haplotipos del gen HBB que presentaron la mutación beta-S en 33 niños con patrón electroforético de hemoglobina AS, mediante reacción en cadena de la polimerasa (PCR) y enzimas de restricción. Se determinaron el patrón electroforético de la hemoglobina, el nivel de hemoglobina fetal y los parámetros hematológicos de cada individuo. Resultados. Los haplotipos de la hemoglobina S encontrados con mayor frecuencia en la muestra analizada son de origen africano y su orden de aparición fue mayor para el haplotipo Bantú (36,4 %), seguido por Senegal (30,3 %), Benín (21,2 %) y Camerún (12,1 %). La electroforesis de hemoglobina confirmó el fenotipo AS; la dosificación de hemoglobina fetal mostró niveles por debajo de 1 % y los parámetros hematológicos analizados mostraron valores normales en el 100 % de los individuos. Conclusión. Los haplotipos de la HbS encontrados con mayor frecuencia en la muestra estudiada eran de origen africano y su distribución variaba de acuerdo con el lugar de prodedencia del individuo. La mayor frecuencia correspodió al haplotipo Bantú.

Introduction. The hemoglobin S (HbS) mutation is accompanied by other mutations in the region of chromosome 11 known as "beta globin cluster". The pattern of combination of these polymorphisms giving rise to the haplotypes that co-inherit the HbS mutation, are called haplotypes bs, and are of great epidemiological and clinical significance. Objective. The frequencies of major haplotypes associated with S beta-globin gene was determined in Colombian patients heterozygous for hemoglobin S. Materials and methods. As part of the national neonatal screening program at Clínica Colsanitas, located in major cities of Colombia, nearly 1,200 children from different areas of the country were examined for hemoglobinopathies. The sickle cell trait was identified as the most common. S beta-globin gene haplotypes were determined by PCR and restriction enzymes in 33 children with AS hemoglobin electrophoretic patterns (carrier state). In addition, electrophoretic patterns of hemoglobin, fetal hemoglobin levels and hematologic parameters of each individual were identified. Results. The most frequent haplotypes in Colombia were the Bantú haplotype (36.4 %), followed by Senegal (30.3 %), Benin (21.2 %) and Cameroon (12.1 %) haplotypes. Hemoglobin electrophoresis confirmed the AS phenotype in all patients, and fetal hemoglobin levels below 1%. Other hematological parameters were normal in all cases. Conclusion. The HbS haplotypes found more frequently in the sample were of African origin, and their distribution varied according to the place of origin of the individual. The most frequent corresponded to the Bantu haplotype.

Uveítis y terapia anti-TNF / Uveitis and anti-TNF therapy

La uveítis es responsable de la pérdida visual hasta del 10% de la población mundial y es la segunda causa de ceguera tratable en personas de edad productiva, después de la retinopatía diabética. El tratamiento de la uveítis no infecciosa depende de su severidad; existe un alto porcentaje (hasta el 40%) de casos refractarios a inmunosupresores y esteroides a dosis altas. El factor de necrosis tumoral (TNF) es una citoquina fundamental en la patogénesis de la uveítis no infecciosa; su bloqueo selectivo con anticuerpos monoclonales y proteínas de fusión ha demostrado, en series de casos, estudios abiertos y pequeños estudios clínicos aleatorizados, eficacia y seguridad en casos idiopáticos y asociados a enfermedades autoinmunes, en la prevención de recaídas, ahorro de esteroides y pronóstico visual a largo plazo. Sin embargo, se han descrito efectos paradójicos, como la inducción de uveítis asociada al uso de proteínas de fusión contra TNF, como etanercept. Se pretende hacer una revisión exhaustiva de la literatura para determinar el papel de los agentes anti-TNF en el tratamiento de la uveítis no infecciosa refractaria.

Uveitis is responsible for visual loss of up to 10% of world population and is the second leading cause of treatable blindness in people of working age, after diabetic retinopathy. The treatment of noninfectious uveitis depends on its severity; there is a high percentage (up to 40%) of cases refractory to immunosuppressants and high-dose corticosteroids. Tumor necrosis factor (TNF) is a key cytokine in the pathogenesis of noninfectious uveitis. Several case reports, open trials and small randomized controlled trials with selective blocking of TNF with monoclonal antibodies (infliximab and adalimumab) and fusion proteins (etanercept) have shown efficacy in the treatment of refractory uveitis, in idiopathic and associated with autoimmune diseases, in preventing relapses, steroid-sparing effect and improvement of long-term visual prognosis. However, there are some reports of paradoxical effects, such as induction of uveitis associated with the use of etanercept. We performed a thorough review of the literature to determine the role of anti-TNF agents in the treatment of refractory non-infectious uveitis.

Arrinia congénita / Congenitalarrhinia

Introducción. La arrinia congénita es una anomalía craneofacial rara, la cual se presenta en forma aislada o asociada a otros defectos, o bien puede ser componente de un síndrome o alteración genética. El tratamiento dependerá de la extensión y gravedad del defecto, pero es fundamental establecer una vía aérea permeable.Caso clínico. Se presenta el caso de un recién nacido de 37 semanas de edad gestacional, de 8 horas de vida extrauterina y con arrinia congénita, sin antecedentes heredo-familiares de importancia y que cursó con dificultad respiratoria grave que requirió de traqueostomía. Como defecto asociado presentó agenesia del cuerpo calloso.Conclusión. El tratamiento primario de los pacientes con arrinia congénita consiste en establecer una vía aérea permeable, siendo la traqueostomía el procedimiento quirúrgico de elección. La corrección definitiva del defecto dependerá de la gravedad del mismo y debido a la escasa frecuencia de estos defectos aún no existen lineamientos bien definidos; sin embargo, es importante que el abordaje sea integral y que se proporcione apoyo psicológico tanto a la familia como al paciente.