ABSTRACT
We report here the virtual screening design, synthesis and activity of eight new inhibitors of SphK1. For this study we used a pre-trained Graph Convolutional Network (GCN) combined with docking calculations. This exploratory analysis proposed nine compounds from which eight displayed significant inhibitory effect against sphingosine kinase 1 (SphK1) demonstrating a high level of efficacy for this approach. Four of these compounds also displayed anticancer activity against different tumor cell lines, and three of them (5), (6) and (7) have shown a wide inhibitory action against many of the cancer cell line tested, with GI50 below 5 µM, being (5) the most promising with TGI below 10 µM for the half of cell lines. Our results suggest that the three most promising compounds reported here are the pyrimidine-quinolone hybrids (1) and (6) linked by p-aminophenylsulfanyl and o-aminophenol fragments respectively, and (8) without such aryl linker. We also performed an exhaustive study about the molecular interactions that stabilize the different ligands at the binding site of SphK1. This molecular modeling analysis was carried out by using combined techniques: docking calculations, MD simulations and QTAIM analysis. In this study we also included PF543, as reference compound, in order to better understand the molecular behavior of these ligands at the binding site of SphK1.These results provide useful information for the design of new inhibitors of SphK1 possessing these structural scaffolds.
Subject(s)
Antineoplastic Agents , Phosphotransferases (Alcohol Group Acceptor) , Quinolones , Quinolones/pharmacology , Protein Kinase Inhibitors , Antineoplastic Agents/chemistry , Models, Molecular , Cell Line, Tumor , Molecular Docking Simulation , Drug Screening Assays, Antitumor , Cell Proliferation , Structure-Activity Relationship , Molecular StructureABSTRACT
Introduction: Macroglossia as a clinical manifestation of systemic amyloidosis is a rare condition, occurring in less than 9% of all types of amyloidosis. The aim of this report is to present the diagnostic approach of a patient with macroglossia, providing a systematic approach and considering relevant diagnostic possibilities during their evaluation. Clinical case: We present the case of a 60-year-old man who presented with a progressively enlarging giant tongue for six months, causing dysphagia and reduced oral opening. A tongue biopsy was taken, which histopathologically exhibited homogenous eosinophilic amyloid-like material. Congo red staining showed amyloid material with red dye under light microscopy and apple-green birefringence under polarized light. Bone marrow biopsy showed 30% plasma cells, allowing for a definitive diagnosis of soft tissue amyloidosis. Although it is a benign lesion, localized amyloidosis should be differentiated from systemic forms. Conclusions: The approach of patients with macroglossia is complex due to the diagnostic possibilities, from endocrinological causes, neoplastic, and even by deposit; Being an isolated sign in a patient is a challenge in its approach, because the involvement of the airway is the main complication to avoid in these patients.
Introducción: la macroglosia, como manifestación clínica de la amiloidosis sistémica, es una condición poco frecuente, ya que ocurre en menos del 9% de todos los tipos de amiloidosis. El objetivo de este informe es presentar el abordaje diagnóstico de un paciente con macroglosia, proporcionando un enfoque sistemático y considerando las posibilidades diagnósticas relevantes durante su evaluación. Caso clínico: presentamos el caso de un hombre de 60 años que presentó una lengua gigante de crecimiento progresivo durante seis meses, lo que causó disfagia y reducción en la apertura oral. Se realizó una biopsia de la lengua, la cual histopatológicamente exhibió material homogéneo similar a un amiloide eosinofílico. La tinción de rojo Congo mostró material amiloide con colorante rojo bajo microscopía óptica y con birrefringencia verde manzana bajo luz polarizada. La biopsia de médula ósea mostró un 30% de células plasmáticas, lo que permitió realizar un diagnóstico definitivo de amiloidosis de tejidos blandos. Aunque se trata de una lesión benigna, la amiloidosis localizada debe diferenciarse de las formas sistémicas. Conclusiones: el abordaje de pacientes con macroglosia es complejo, debido a las diversas posibilidades diagnósticas, que incluyen causas endocrinológicas, neoplásicas e, incluso, por deposición de sustancias. Cuando se presenta como un signo aislado en un paciente, se convierte en un reto en su abordaje, ya que la principal complicación a evitar en estos pacientes es el compromiso de la vía aérea.
Subject(s)
Amyloidosis , Deglutition Disorders , Macroglossia , Male , Humans , Middle Aged , Macroglossia/etiology , Deglutition Disorders/diagnosis , Deglutition Disorders/etiology , Amyloidosis/complications , Amyloidosis/diagnosis , Congo RedABSTRACT
Over the last years, the incidence of melanoma, the deadliest form of skin cancer, has risen significantly. Nearly half of the melanoma patients exhibit the BRAFV600E mutation. Although the use of BRAF and MEK inhibitors (BRAFi and MEKi) showed an impressive success rate in melanoma patients, durability of response remains an issue because tumor quickly becomes resistant. Here, we generated and characterized Lu1205 and A375 melanoma cells resistant to vemurafenib (BRAFi). Resistant cells (Lu1205R and A375R) exhibit higher IC50 (5-6 fold increase) and phospho-ERK levels and 2-3 times reduced apoptosis than their sensitive parents (Lu1205S and A375S). Moreover, resistant cells are 2-3 times bigger, display a more elongated morphology and have a modulation of migration capacity. Interestingly, pharmacological inhibition of sphingosine kinases, that prevents sphingosine-1-phosphate production, reduces migration of Lu1205R cells by 50 %. In addition, although Lu1205R cells showed increased basal levels of the autophagy markers LC3II and p62, they have decreased autophagosome degradation and autophagy flux. Remarkably, expression of Rab27A and Rab27B, which are involved in the release of extracellular vesicles are dramatically augmented in resistant cells (i.e. 5-7 fold increase). Indeed, conditioned media obtained from Lu1205R cells increased the resistance to vemurafenib of sensitive cells. Hence, these results support that resistance to vemurafenib modulates migration and the autophagic flux and may be transferred to nearby sensitive melanoma cells by factors that are released to the extracellular milieu by resistant cells.
Subject(s)
Melanoma , Proto-Oncogene Proteins B-raf , Humans , Vemurafenib/pharmacology , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins B-raf/metabolism , Sulfonamides/pharmacology , Indoles/pharmacology , Drug Resistance, Neoplasm/genetics , Cell Line, Tumor , Xenograft Model Antitumor Assays , Melanoma/drug therapy , Melanoma/genetics , Melanoma/metabolism , Protein Kinase Inhibitors/pharmacology , AutophagyABSTRACT
Neuroblastoma, the most common extracranial solid tumor occurring in childhood, originates from the aberrant proliferation of neural crest cells. Accordingly, the mechanism underling neuronal differentiation could provide new strategies for neuroblastoma treatment. It is well known that neurite outgrowth could be induced by Angiotensin II (Ang II) AT2 receptors; however, the signaling mechanism and its possible interaction with NGF (neural growth factor) receptors remain unclear. Here, we show that Ang II and CGP42112A (AT2 receptor agonist) promote neuronal differentiation by inducing neurite outgrowth and ßIII-tubulin expression in SH-SY5Y neuroblastoma cells. In addition, we demonstrate that treatment with PD123319 (AT2 receptor antagonist) reverts Ang II or CGP42112A-induced differentiation. By using specific pharmacological inhibitors we established that neurite outgrowth induced by CGP42112A requires the activation of MEK (mitogen-activated protein kinase kinase), SphK (sphingosine kinase) and c-Src but not PI3K (phosphatidylinositol 3-kinase). Certainly, CGP42112A stimulated a rapid and transient (30 s, 1 min) phosphorylation of c-Src at residue Y416 (indicative of activation), following by a Src deactivation as indicated by phosphorylation of Y527. Moreover, inhibition of the NGF receptor tyrosine kinase A (TrkA) reduced neurite outgrowth induced by Ang II and CGP42112A. In summary, we demonstrated that AT2 receptor-stimulated neurite outgrowth in SH-SY5Y cells involves the induction of MEK, SphK and c-Src and suggests a possible transactivation of TrkA. In that regard, AT2 signaling pathway is a key player in neuronal differentiation and might be a potential target for therapeutic treatments.
ABSTRACT
We measured submicron aerosols (PM1) at a beachfront site in Texas in Spring 2021 to characterize the "background" aerosol chemical composition advecting into Texas and the factors controlling this composition. Observations show that marine "background" aerosols from the Gulf of Mexico were highly processed and acidic; sulfate was the most abundant component (on average 57% of total PM1 mass), followed by organic material (26%). These chemical characteristics are similar to those observed at other marine locations globally. However, Gulf "background" aerosols were much more polluted; the average non-refractory (NR-) PM1 mass concentration was 3-70 times higher than that observed in other clean marine atmospheres. Anthropogenic shipping emissions over the Gulf of Mexico explain 78.3% of the total measured "background" sulfate in the Gulf air. We frequently observed haze pollution in the air mass from the Gulf, with significantly elevated concentrations of sulfate, organosulfates, and secondary organic aerosol associated with sulfuric acid. Analysis suggests that aqueous oxidation of shipping emissions over the Gulf of Mexico by peroxides in the particles might potentially be an important pathway for the rapid production of acidic sulfate and organosulfates during the haze episodes under acidic conditions.
Subject(s)
Air Pollutants , Sulfates , Sulfates/analysis , Air Pollutants/analysis , Gulf of Mexico , Oxidation-Reduction , Sulfur Oxides/analysis , Aerosols/analysis , Particulate Matter/analysis , Environmental Monitoring , ChinaABSTRACT
La parálisis radial neonatal aislada (PRNA) es un cuadro clínico infrecuente que debe distinguirse de otras entidades más frecuentes, como la parálisis braquial obstétrica (PBO). Debemos sospechar una PRNA en neonatos que presentan incapacidad para la extensión de muñeca y de dedos, pero mantienen intacta la función del deltoides, del bíceps, y del tríceps, así como la flexión de muñeca y de dedos. Mientras la PBO tiene una evolución clínica variable dependiendo de la extensión de la lesión neurológica, la PRNA presenta una resolución espontánea, independientemente del grado de afectación inicial. Presentamos el caso de un recién nacido con PRNA cuyo diagnóstico inicial fue de PBO.
Isolated radial nerve palsy (IRNP) in the newborn is a rare clinical condition that must be distinguished from entities that are more common, such brachial plexus birth palsy (BPBP). It should be suspected in newborns presenting with absent wrist and digital extension but intact deltoid, biceps, and triceps function, as well as wrist and digital flexor function. Whereas BPBP is highly variable depending on the extent of the neurological involvement, IRNP resolves spontaneously, regardless of the severity of the initial presentation. We herein present a case of newborn with IRNP whose initial diagnosis was of BPBP.
Subject(s)
Humans , Male , Infant, Newborn , Radial Neuropathy/diagnosis , Radial Neuropathy/rehabilitation , Physical Therapy ModalitiesABSTRACT
Background: Myositis ossificans progressiva (MOP) is a low prevalence hereditary connective tissue disease (1:2,000,000 habitants). It is characterized by heterotopic ossification with an uncertain behavior that has been exceptionally related to neoplasms. The objective was to know the coexistence of MOP with neoplasms of mesodermal origin, so that they can be considered in the diagnosis of other patients, as well as formulate hypotheses to clarify their association. Clinical case: 27-year-old female with right gluteal and ischitiobial muscle pain that increased with exercise, without remission with analgesics until limiting the mobility of both extremities. A bone series was requested where areas of heterogeneous radiolucency were evidenced in the region of, both, thighs and pelvis in an irregular manner, similar to bone density, which was compatible with the ultrasound and tomographic findings; we concluded that they were images of myositis ossificans of the hip. The patient reported gastric symptoms and an endoscopy was requested, which histopathologically reported diffuse gastric carcinoma with signet ring cells; cabinet images showed an ovarian tumor. Conclusion: MOP is a low prevalence disease, which is why its knowledge and suspicion are essential for the diagnosis. We found little literature that involves the three entities; therefore, their pathophysiology and understanding is limited. Regarding MOP, at this moment there is no curative treatment; however, an accurate diagnosis allows to start rehabilitation in a timely manner with an improvement in the quality of life.
Introducción: la miositis osificante progresiva (MOP) es una enfermedad hereditaria del tejido conectivo de baja prevalencia (1:2,000,000 habitantes). Se caracteriza por osificación heterotópica con un comportamiento incierto que excepcionalmente se ha relacionado con neoplasias. Se buscó conocer la coexistencia de la MOP con neoplasias de origen mesodérmico, para que sean consideradas en el diagnóstico de otros pacientes, así como formular hipótesis para esclarecer su asociación. Caso clínico: mujer de 27 años con dolor de músculo isquitiobial y glúteo derecho que incrementaba con el ejercicio, sin remisión con analgésicos hasta limitar la movilidad de ambas extremidades. Se solicitó una serie ósea donde se evidenciaron zonas de radiolucidez heterogénea en la región de ambos muslos y pelvis de manera irregular, semejante a densidad ósea, que fue compatible con los hallazgos ecográficos y tomográficos; se concluyó que eran imágenes relacionadas con miositis osificante de cadera. La paciente refirió sintomatología gástrica y se solicitó una endoscopía que histopatológicamente reportó carcinoma gástrico difuso con células en anillo de sello; las imágenes de gabinete mostraron tumoración ovárica. Conclusión: la MOP es una patología de baja prevalencia, por lo que su conocimiento y sospecha son fundamentales para el diagnóstico. Hay poca literatura que involucre a las tres entidades; por ende, su fisiopatología y comprensión es limitada. En cuanto a la MOP, aún no hay un tratamiento curativo; sin embargo, el diagnóstico certero permite iniciar rehabilitación de manera oportuna con mejoría de la calidad de vida.
Subject(s)
Connective Tissue Diseases , Myositis Ossificans , Adult , Exercise , Female , Humans , Myositis Ossificans/diagnosis , Myositis Ossificans/pathology , Myositis Ossificans/therapy , Quality of Life , Tomography, X-Ray Computed/methodsABSTRACT
INTRODUCTION: Females may have greater susceptibility to Alzheimer's disease (AD)-pathology. We examined the effect of sex on pathology, neurodegeneration, and memory in cognitively-unimpaired Presenilin-1 (PSEN1) E280A mutation carriers and non-carriers. METHODS: We analyzed baseline data from 167 mutation carriers and 75 non-carriers (ages 30 to 53) from the Alzheimer's Prevention Initiative Autosomal Dominant AD Trial, including florbetapir- and fludeoxyglucose-PET, MRI based hippocampal volume and cognitive testing. RESULTS: Females exhibited better delayed recall than males, controlling for age, precuneus glucose metabolism, and mutation status, although the effect was not significant among PSEN1 mutation carriers only. APOE ε4 did not modify the effect of sex on AD biomarkers and memory. DISCUSSION: Our findings suggest that, among cognitively-unimpaired individuals at genetic risk for autosomal-dominant AD, females may have greater cognitive resilience to AD pathology and neurodegeneration than males. Further investigation of sex-specific differences in autosomal-dominant AD is key to elucidating mechanisms of AD risk and resilience.
Subject(s)
Alzheimer Disease , Adult , Female , Humans , Male , Middle Aged , Alzheimer Disease/metabolism , Cognition , Colombia , Neuropsychological Tests , Presenilin-1/genetics , Sex CharacteristicsABSTRACT
Introducción: La osteosíntesis percutánea sacroiliaca guiada por radioscopia en lesiones del anillo pélvico posterior sigue siendo la técnica de referencia. Sin embargo, el desarrollo de técnicas como la cirugía asistida por navegación 2D/3D o por tomografía han mejorado la facilidad y seguridad en la colocación de los tornillos. Objetivo: Presentar la técnica de fijación asistida por navegación en 2D y los resultados clínicos y radiológicos obtenidos. Materiales y métodos: Se revisaron 23 pacientes con disrupción del anillo pélvico posterior (luxación y/o fractura sacroiliaca) intervenidos mediante fijación percutánea asistida por navegación 2D (Sistema Synergy de Medtronic®) en el hospital desde 2017 hasta la actualidad. Se recogieron variables demográficas, de clasificación, terapéuticas y las complicaciones derivadas. Se utilizó la escala modificada de valoración POS (Multicenter Study Group Pelvis Outcome Scale) para evaluar el resultado clínico, radiológico y social. Resultados: Ocho pacientes presentaban luxación sacro-iliaca y 15 tenían fractura a través del sacro. Se implantaron 40 tornillos iliacosacros. El tiempo quirúrgico medio fue de 20 minutos para cada tornillo. Fueron necesarios ocho pulsos de radioscopia de media por intervención. Hubo tres tornillos (7.5%) mal posicionados. 15 pacientes obtuvieron un resultado bueno o excelente en el formulario POS. Conclusiones: La técnica asistida por navegación es una alternativa con buenos resultados. Facilita al cirujano la colocación correcta de los tornillos en el corredor óseo sacro, acortando el tiempo quirúrgico y con una menor exposición a radiaciones ionizantes. Es útil para todo tipo de lesiones del anillo y cuando son necesarias maniobras de reducción.
Introduction: Radioscopy-guided percutaneous sacroiliac osteosynthesis in posterior pelvic ring lesions continues to be the reference technique. However, the development of techniques such as surgery assisted by 2D/3D navigation or tomography have improved the ease and safety in screw placement. Objective: To present the 2D navigation-assisted fixation technique and the clinical and radiological results obtained. Materials and methods: 23 patients with disruption of the posterior pelvic ring (dislocation and/or sacroiliac fracture) who underwent percutaneous fixation assisted by 2D navigation (Medtronic® Synergy System) at the hospital from 2017 to the present were reviewed. Demographic, classification, therapeutic variables and resulting complications were collected. The modified POS (Multicenter Study Group Pelvis Outcome Scale) assessment scale was used to evaluate the clinical, radiological and social outcome. Results: Eight patients had sacro-iliac dislocation and 15 had a fracture through the sacrum. 40 iliacosacral screws were implanted. The average surgical time was 20 minutes for each screw. An average of eight fluoroscopy pulses were necessary per intervention. There were three screws (7.5%) incorrectly positioned. 15 patients had a good or excellent result on the POS form. Conclusions: The navigation-assisted technique is an alternative with good results. It makes it easier for the surgeon to correctly place the screws in the sacral bone corridor, shortening surgical time and with less exposure to ionizing radiation. It is useful for all types of ring injuries and when reduction maneuvers are necessary.
ABSTRACT
Introducción: la miositis osificante progresiva (MOP) es una enfermedad hereditaria del tejido conectivo de baja prevalencia (1:2,000,000 habitantes). Se caracteriza por osificación heterotópica con un comportamiento incierto que excepcionalmente se ha relacionado con neoplasias. Se buscó conocer la coexistencia de la MOP con neoplasias de origen mesodérmico, para que sean consideradas en el diagnóstico de otros pacientes, así como formular hipótesis para esclarecer su asociación. Caso clínico: mujer de 27 años con dolor de músculo isquitiobial y glúteo derecho que incrementaba con el ejercicio, sin remisión con analgésicos hasta limitar la movilidad de ambas extremidades. Se solicitó una serie ósea donde se evidenciaron zonas de radiolucidez heterogénea en la región de ambos muslos y pelvis de manera irregular, semejante a densidad ósea, que fue compatible con los hallazgos ecográficos y tomográficos; se concluyó que eran imágenes relacionadas con miositis osificante de cadera. La paciente refirió sintomatología gástrica y se solicitó una endoscopía que histopatológicamente reportó carcinoma gástrico difuso con células en anillo de sello; las imágenes de gabinete mostraron tumoración ovárica. Conclusión: la MOP es una patología de baja prevalencia, por lo que su conocimiento y sospecha son fundamentales para el diagnóstico. Hay poca literatura que involucre a las tres entidades; por ende, su fisiopatología y comprensión es limitada. En cuanto a la MOP, aún no hay un tratamiento curativo; sin embargo, el diagnóstico certero permite iniciar rehabilitación de manera oportuna con mejoría de la calidad de vida.
Background: Myositis ossificans progressiva (MOP) is a low prevalence hereditary connective tissue disease (1:2,000,000 habitants). It is characterized by heterotopic ossification with an uncertain behavior that has been exceptionally related to neoplasms. The objective was to know the coexistence of MOP with neoplasms of mesodermal origin, so that they can be considered in the diagnosis of other patients, as well as formulate hypotheses to clarify their association. Clinical case: 27-year-old female with right gluteal and ischitiobial muscle pain that increased with exercise, without remission with analgesics until limiting the mobility of both extremities. A bone series was requested where areas of heterogeneous radiolucency were evidenced in the region of, both, thighs and pelvis in an irregular manner, similar to bone density, which was compatible with the ultrasound and tomographic findings; we concluded that they were images of myositis ossificans of the hip. The patient reported gastric symptoms and an endoscopy was requested, which histopathologically reported diffuse gastric carcinoma with signet ring cells; cabinet images showed an ovarian tumor. Conclusion: MOP is a low prevalence disease, which is why its knowledge and suspicion are essential for the diagnosis. We found little literature that involves the three entities; therefore, their pathophysiology and understanding is limited. Regarding MOP, at this moment there is no curative treatment; however, an accurate diagnosis allows to start rehabilitation in a timely manner with an improvement in the quality of life.
Subject(s)
Humans , Female , Adult , Bone Neoplasms , Ossification, Heterotopic , Myositis Ossificans , Diagnostic Imaging , Bone Density , Risk FactorsABSTRACT
INTRODUCTION: Cortical thinning is a marker of neurodegeneration in Alzheimer's disease (AD). We investigated the age-related trajectory of cortical thickness across the lifespan (9-59 years) in a Colombian kindred with autosomal dominant AD (ADAD). METHODS: Two hundred eleven participants (105 presenilin-1 [PSEN1] E280A mutation carriers, 16 with cognitive impairment; 106 non-carriers) underwent magnetic resonance imaging. A piecewise linear regression identified change-points in the age-related trajectory of cortical thickness in carriers and non-carriers. RESULTS: Unimpaired carriers exhibited elevated cortical thickness compared to non-carriers, and thickness more negatively correlated with age and cognition in carriers relative to non-carriers. We found increased cortical thickness in child carriers, after which thickness steadied compared to non-carriers prior to a rapid reduction in the decade leading up to the expected age at cognitive impairment in carriers. DISCUSSION: Findings suggest that cortical thickness may fluctuate across the ADAD lifespan, from early-life increased thickness to atrophy proximal to clinical onset.
ABSTRACT
BACKGROUND: Cardiovascular risk factors increase the risk of developing dementia, including Alzheimer's disease and vascular dementia. OBJECTIVE: Studying individuals with autosomal dominant mutations leading to the early onset of dementia, this study examines the effect of the global cardiovascular risk profile on early cognitive and neuroimaging features of Alzheimer's disease and vascular dementia. METHODS: We studied 85 non-demented and stroke-free individuals, including 20 subjects with Presenilin1 (PSEN1) E280A mutation leading to the early onset of autosomal dominant Alzheimer's disease (ADAD), 20 subjects with NOTCH3 mutations leading to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and to the early onset of vascular dementia, and 45 non-affected family members (non-carriers). All subjects underwent clinical and neuropsychological evaluations and an MRI. The global cardiovascular risk profile was estimated using the office-based Framingham Cardiovascular Risk Profile (FCRP) score. RESULTS: In individuals with CADASIL, a higher FCRP score was associated with a reduced hippocampal volume (Bâ=â-0.06, pâ<â0.05) and an increased severity of cerebral microbleeds (Bâ=â0.13, pâ<â0.001), lacunes (Bâ=â0.30, pâ<â0.001), and perivascular space enlargement in the basal ganglia (Bâ=â0.50, pâ<â0.05). There was no significant association between the FCRP score and neuroimaging measures in ADAD or non-carrier subjects. While the FCRP score was related to performance in executive function in non-carrier subjects (Bâ=â0.06, pâ<â0.05), it was not significantly associated with cognitive performance in individuals with CADASIL or ADAD. CONCLUSION: Our results suggest that individuals with CADASIL and other forms of vascular cognitive impairment might particularly benefit from early interventions aimed at controlling cardiovascular risks.
Subject(s)
Alzheimer Disease , Brain , Dementia, Vascular , Presenilin-1/genetics , Receptor, Notch3/genetics , Alzheimer Disease/diagnosis , Alzheimer Disease/epidemiology , Alzheimer Disease/genetics , Alzheimer Disease/prevention & control , Brain/diagnostic imaging , Brain/pathology , Colombia/epidemiology , Dementia, Vascular/diagnosis , Dementia, Vascular/epidemiology , Dementia, Vascular/genetics , Dementia, Vascular/prevention & control , Early Diagnosis , Family , Female , Heart Disease Risk Factors , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Mutation , Neuropsychological Tests , Preventive Health Services/methods , Risk Factors , Risk Reduction BehaviorABSTRACT
The type III secretion systems (T3SS) encoded in pathogenicity islands SPI-1 and SPI-2 are key virulence factors of Salmonella. These systems translocate proteins known as effectors into eukaryotic cells during infection. To characterize the functionality of T3SS effectors, gene fusions to the CyaA' reporter of Bordetella pertussis are often used. CyaA' is a calmodulin-dependent adenylate cyclase that is only active within eukaryotic cells. Thus, the translocation of an effector fused to CyaA' can be evaluated by measuring cAMP levels in infected cells. Here, we report the construction of plasmids pCyaA'-Kan and pCyaA'-Cam, which contain the ORF encoding CyaA' adjacent to a cassette that confers resistance to kanamycin or chloramphenicol, respectively, flanked by Flp recombinase target (FRT) sites. A PCR product from pCyaA'-Kan or pCyaA'-Cam containing these genetic elements can be introduced into the bacterial chromosome to generate gene fusions by homologous recombination using the Red recombination system from bacteriophage λ. Subsequently, the resistance cassette can be removed by recombination between the FRT sites using the Flp recombinase. As a proof of concept, the plasmids pCyaA'-Kan and pCyaA'-Cam were used to generate unmarked chromosomal fusions of 10 T3SS effectors to CyaA' in S. Typhimurium. Each fusion protein was detected by Western blot using an anti-CyaA' monoclonal antibody when the corresponding mutant strain was grown under conditions that induce the expression of the native gene. In addition, T3SS-1-dependent secretion of fusion protein SipA-CyaA' during in vitro growth was verified by Western blot analysis of culture supernatants. Finally, efficient translocation of SipA-CyaA' into HeLa cells was evidenced by increased intracellular cAMP levels at different times of infection. Therefore, the plasmids pCyaA'-Kan and pCyaA'-Cam can be used to generate unmarked chromosomal cyaA' translational fusion to study regulated expression, secretion and translocation of Salmonella T3SS effectors into eukaryotic cells.
ABSTRACT
BACKGROUND: Neuroimaging studies of autosomal dominant Alzheimer's disease (ADAD) enable characterization of the trajectories of cerebral amyloid-ß (Aß) and tau accumulation in the decades prior to clinical symptom onset. Longitudinal rates of regional tau accumulation measured with positron emission tomography (PET) and their relationship with other biomarker and cognitive changes remain to be fully characterized in ADAD. METHODS: Fourteen ADAD mutation carriers (Presenilin-1 E280A) and 15 age-matched non-carriers from the Colombian kindred underwent 2-3 sessions of Aß (11C-Pittsburgh compound B) and tau (18F-flortaucipir) PET, structural magnetic resonance imaging, and neuropsychological evaluation over a 2-4-year follow-up period. Annualized rates of change for imaging and cognitive variables were compared between carriers and non-carriers, and relationships among baseline measurements and rates of change were assessed within carriers. RESULTS: Longitudinal measurements were consistent with a sequence of ADAD-related changes beginning with Aß accumulation (16 years prior to expected symptom onset, EYO), followed by entorhinal cortex (EC) tau (9 EYO), neocortical tau (6 EYO), hippocampal atrophy (6 EYO), and cognitive decline (4 EYO). Rates of tau accumulation among carriers were most rapid in parietal neocortex (~ 9%/year). EC tau PET signal at baseline was a significant predictor of subsequent neocortical tau accumulation and cognitive decline within carriers. CONCLUSIONS: Our results are consistent with the sequence of biological changes in ADAD implied by cross-sectional studies and highlight the importance of EC tau as an early biomarker and a potential link between Aß burden and neocortical tau accumulation in ADAD.
Subject(s)
Alzheimer Disease , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/genetics , Amyloid beta-Peptides , Biomarkers , Boston , Colombia , Cross-Sectional Studies , Humans , Magnetic Resonance Imaging , Positron-Emission Tomography , tau Proteins/geneticsABSTRACT
The role of tumor necrosis factor-α (TNF-α) in shaping the tumor microenvironment is ambiguous. Consistent with its uncertain role in melanoma, TNF-α plays a dual role, either acting as a cytotoxic cytokine or favoring a tumorigenic inflammatory microenvironment. TNF-α signals via two cognate receptors, namely TNFR1 (p55) and TNFR2 (p75), which mediate divergent biological activities. Here, we analyzed the impact of TNFR1 deficiency in tumor progression in the B16.F1 melanoma model. Tumors developed in mice lacking TNFR1 (TNFR1 knock-out; KO) were smaller and displayed lower proliferation compared to their wild type (WT) counterpart. Moreover, TNFR1 KO mice showed reduced tumor angiogenesis. Although no evidence of spontaneous metastases was observed, conditioned media obtained from TNFR1 KO tumors increased tumor cell migration. Whereas the analysis of tumor-associated immune cell infiltrates showed similar frequency of total and M2-polarized tumor-associated macrophages (TAMs), the percentage of CD8+ T cells was augmented in TNFR1 KO tumors. Indeed, functional ex vivo assays demonstrated that CD8+ T cells obtained from TNFR1KO mice displayed an increased cytotoxic function. Thus, lack of TNFR1 attenuates melanoma growth by modulating tumor cell proliferation, migration, angiogenesis and CD8+ T cell accumulation and activation, suggesting that interruption of TNF-TNFR1 signaling may contribute to control tumor burden.
Subject(s)
CD8-Positive T-Lymphocytes/immunology , Melanoma, Experimental/blood supply , Melanoma, Experimental/immunology , Neovascularization, Pathologic/immunology , Receptors, Tumor Necrosis Factor, Type I/deficiency , Animals , Cell Proliferation , Lymphocyte Activation/immunology , Melanins/metabolism , Melanoma, Experimental/pathology , Mice, Inbred C57BL , Mice, Knockout , Neoplasm Invasiveness , Receptors, Tumor Necrosis Factor, Type I/metabolism , Signal Transduction , Tumor Microenvironment/immunologyABSTRACT
The oncogenic mutated kinase BRAFV600E is an attractive molecular target because it is expressed in several human cancers, including melanoma. To present, only three BRAF small inhibitors are approved by the FDA for the treatment of patients with metastatic melanoma: Vemurafenib, Dabrafenib and Encorafenib. Although many protocol treatments have been probed in clinical trials, BRAF inhibition has a limited effectiveness because patients invariably develop resistance and secondary toxic effects associated with the therapy. These limitations highlight the importance of designing new and better inhibitors with different structures that could establish different interactions in the active site of the enzyme and therefore decrease resistance progress. Considering the data from our previous report, here we studied two series of derivatives of structural scaffolds as potential BRAF inhibitors: hydroxynaphthalenecarboxamides and substituted piperazinylpropandiols. Our results indicate that structural analogues of substituted piperazinylpropandiols do not show significantly better activities to that previously reported. In contrast, the hydroxynaphthalenecarboxamides derivatives significantly inhibited cell viability and ERK phosphorylation, a measure of BRAF activity, in Lu1205 BRAFV600E melanoma cells. In order to better understand these experimental results, we carried out a molecular modeling study using different combined techniques: docking, MD simulations and quantum theory of atoms in molecules (QTAIM) calculations. Thus, by using this approach we determined that the molecular interactions that stabilize the different molecular complexes are closely related to Vemurafenib, a well-documented BRAF inhibitor. Furthermore, we found that bi-substituted compounds may interact more strongly respect to the mono-substituted analogues, by establishing additional interactions with the DFG-loop at the BRAF-active site. On the bases of these results we synthesized and tested a new series of hydroxynaphthalenecarboxamides bi-substituted. Remarkably, all these compounds displayed significant inhibitory effects on the bioassays performed. Thus, the structural information reported here is important for the design of new BRAFV600E inhibitors possessing this type of structural scaffold.
Subject(s)
Antineoplastic Agents/therapeutic use , Melanoma/drug therapy , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Humans , Models, Molecular , PhosphorylationABSTRACT
BACKGROUND: The hemophagocytic lymphohistiocytosis is a disease with a potential fatal evolution, caused by the activation of macrophages and histiocytes with hemophagocytosis in bone marrow and other reticuloendothelial systems, triggered by a defect in the T lymphocyte when stimulating the production of interleukin 1-beta, interleukin 6, interferon-gamma and tumor necrosis factor-alpha that promote macrophage activation. This condition presents with fever, cytopenias, splenomegaly, hemophagocytosis in bone marrow, hypertriglyceridemia and hypofibrinogenemia, in the context of an infectious, neoplastic or autoimmune disease. The objective of this article is to describe the utility of intravenous immunoglobulin (IVIg) in patients unable to receive immunosuppressive treatment. CASE REPORTS: We present two case reports of systemic lupus erythematosus (SLE) with macrophage activation syndrome (MAS), one of them associated with central nervous system vasculitis and the other one with febrile neutropenia, both with bacterial infection added. CONCLUSIONS: The diagnosis of MAS should be suspected in all patients with lupus activity, fever, cytopenias, visceromegalies, hypertriglyceridemia and hypofibrinogenemia. Diagnosis and treatment are important to significantly reduce mortality. It is proposed that the first line treatment in patients that present SLE associated with MAS and sepsis should be IgIV and as a second line immunosuppressants with intravenous steroids.
INTRODUCCIÓN: La linfohistiocitosis hemofagocítica es una enfermedad de evolución potencialmente fatal, caracterizada por la activación de macrófagos y de histiocitos con hemofagocitosis en la médula ósea y en otros sistemas reticuloendoteliales, desencadenada por un defecto en los linfocitos T al estimular la producción de interleucina 1-beta, interleucina 6, interferón gamma y factor de necrosis tumoral alfa, que promueven la activación de los macrófagos. Esta afección cursa con fiebre, citopenias, esplenomegalia, hemofagocitosis en la médula ósea, hipertrigliceridemia e hipofibrinogenemia, en el contexto de una enfermedad infecciosa, neoplásica o autoinmunitaria. El objetivo de este artículo es describir la utilidad de la inmunoglobulina intravenosa (IgIV) en pacientes que no pueden recibir tratamiento inmunosupresor. CASOS CLÍNICOS: Se presentan dos casos de lupus eritematoso sistémico (LES) con síndrome de activación macrofágica (SAM), uno asociado a vasculitis del sistema nervioso central y otro a neutropenia febril, ambos con infección bacteriana agregada. CONCLUSIONES: El diagnóstico de SAM en pacientes con actividad lúpica se debe sospechar en caso de fiebre, citopenias, visceromegalias, hipertrigliceridemia e hipofibrinogenemia. Un diagnóstico y un tratamiento oportunos son importantes para disminuir de manera considerable la mortalidad. Se propone que el tratamiento de primera línea en los pacientes con LES asociado a SAM y sepsis sea la IgIV, y como segunda línea un inmunosupresor con un esteroide intravenoso.
ABSTRACT
INTRODUCCIÓN: Los siringomas son tumores benignos derivados de la porción intraepidérmica de los conductos sudoríparos ecrinos. Ocasionalmente pueden iniciar de forma súbita como siringomas eruptivos o localizarse en sitios atípicos que retrasan el diagnóstico por años. La dermatoscopía tiene un rol incipiente en diferenciar siringomas de su extenso diagnóstico diferencial. MÉTODOS: Estudio retrospectivo descriptivo de serie de casos de siringomas de localización atípica. Los datos fueron extraídos de fichas clínicas electrónicas. Todos incluyen dermatoscopía y correlación histopatológica. RESULTADOS: Cinco pacientes. Cuatro hombres y una mujer entre 40 y 79 años de edad con siringomas atípicos: cuatro casos eruptivos y un caso de siringomas vulvares. DISCUSIÓN: Proponemos la dermatoscopía basada en nuestros hallazgos como una herramienta útil con estructuras ovales amarillas y una pseudo-red café clara difusa en su superficie. Estas estructuras amarillas se pueden correlacionar con la proliferación ductal ecrina y el denso estroma en la histopatología. CONCLUSIÓN: Enfatizamos que se debe considerar esta entidad en el diagnóstico diferencial de dermatosis papulares y conocer sus manifestaciones clínicas para optimizar la sospecha diagnóstica.
INTRODUCCTION: Syringomas are common benign tumors, probably of origin derived from the intraepidermal portion of the eccrine sweat ducts. Occasionally they may develop suddenly and extensively as eruptive syringomas or be located in atypical sites delaying the diagnosis for years. Dermoscopy has an incipient role in differentiating syringomas from their extensive differential diagnosis. METHODS: Retrospective descriptive case-series study of atypical location syringomas. Data extraction from clinical history from electronic files. They all include dermoscopy and histopathological correlation. RESULTS: Five patients: Four men and one woman between 40 and 79 years old, with atypical syringomas diagnosis: four eruptive and one vulvar syringomas. DISCUSSION: We propose dermoscopy, based on our findings, as a useful tool to this entity, with its oval yellow structures and a diffuse light-brown network-like structure on its surface. These yellow enlargements may be correlated with the ductal eccrine proliferation and the dense stroma seen in the histopathology. CONCLUSION: We emphasize that they should be considered in the differential diagnosis of papular dermatosis, as they tend to be underdiagnosed, and to know their clinical manifestations to optimize the diagnostic suspicion.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Skin Neoplasms/diagnosis , Sweat Gland Neoplasms/diagnosis , Syringoma/diagnosis , Skin Neoplasms/pathology , Sweat Gland Neoplasms/pathology , Vulvar Neoplasms/diagnosis , Retrospective Studies , Syringoma/pathology , Dermoscopy , Diagnosis, DifferentialABSTRACT
Inorganic polyphosphate (polyP) and its metabolic enzymes are important in several cellular processes related with virulence and antibiotic susceptibility. Accordingly, bacterial polyP synthesis has been proposed as a good target for designing novel antivirulence molecules as alternative to conventional antibiotics. In most pathogenic bacteria, polyphosphate kinase 1 (PPK1), in charge of polyP synthesis from ATP, is widely conserved. Current colorimetric and radioactive polyP synthesis enzymatic assays are not suitable for high-throughput screening of PPK1 inhibitors. Given the ability of polyP to modify the excitation-emission spectra of DAPI (4'-6-diamidino-2-phenylindole), a fluorescence assay was previously developed by using a purified recombinant PPK1 enzyme from Escherichia coli. In this work we have developed a suitable methodology for high-throughput measurement of E. coli PPK1 activity. This platform can be used for the screening putative antimicrobial molecules for related enteropathogenic bacteria.
ABSTRACT
The identification of the V600E activating mutation in the protein kinase BRAF in around 50% of melanoma patients has driven the development of highly potent small inhibitors (BRAFi) of the mutated protein. To date, Dabrafenib and Vemurafenib, two specific BRAFi, have been clinically approved for the treatment of metastatic melanoma. Unfortunately, after the initial response, tumors become resistant and patients develop a progressive and lethal disease, making imperative the development of new therapeutic options. The main objective of this work was to find new BRAF inhibitors with different structural scaffolds than those of the known inhibitors. Our study was carried out in different stages; in the first step we performed a virtual screening that allowed us to identify potential new inhibitors. In the second step, we synthesized and tested the inhibitory activity of the novel compounds founded. Finally, we conducted a molecular modelling study that allowed us to understand interactions at the molecular level that stabilize the formation of the different molecular complexes. Our theoretical and experimental study allowed the identification of four new structural scaffolds, which could be used as starting structures for the design and development of new inhibitors of BRAF. Our experimental data indicate that the most active compounds reduced significantly ERK½ phosphorylation, a measure of BRAF inhibition, and cell viability. Thus, from our theoretical and experimental results, we propose new substituted hydroxynaphthalenecarboxamides, N-(hetero)aryl-piperazinylhydroxyalkylphenylcarbamates, substituted piperazinylethanols and substituted piperazinylpropandiols as initial structures for the development of new inhibitors for BRAF. Moreover, by performing QTAIM analysis, we are able to describe in detail the molecular interactions that stabilize the different Ligand-Receptor complexes. Such analysis indicates which portion of the different molecules must be changed in order to obtain an increase in the binding affinity of these new ligands.