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Canonically, immunoglobulin E (IgE) mediates allergic immune responses by triggering mast cells and basophils to release histamine and type 2 helper cytokines. Here we found that in human systemic lupus erythematosus (SLE), IgE antibodies specific for double-stranded DNA (dsDNA) activated plasmacytoid dendritic cells (pDCs), a type of cell of the immune system linked to viral defense, which led to the secretion of substantial amounts of interferon-α (IFN-α). The concentration of dsDNA-specific IgE found in patient serum correlated with disease severity and greatly potentiated pDC function by triggering phagocytosis via the high-affinity FcÉRI receptor for IgE, followed by Toll-like receptor 9 (TLR9)-mediated sensing of DNA in phagosomes. Our findings expand the known pathogenic mechanisms of IgE-mediated inflammation beyond those found in allergy and demonstrate that IgE can trigger interferon responses capable of exacerbating self-destructive autoimmune responses.
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Autoanticuerpos/inmunología , Autoinmunidad , Inmunoglobulina E/inmunología , Interferones/metabolismo , Anticuerpos Antinucleares/inmunología , Complejo Antígeno-Anticuerpo/inmunología , Complejo Antígeno-Anticuerpo/metabolismo , Linfocitos B/inmunología , Linfocitos B/metabolismo , Citocinas/sangre , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/metabolismo , Nefritis Lúpica/inmunología , Nefritis Lúpica/patología , Masculino , Fagocitosis/inmunología , Fagosomas/metabolismo , Células Plasmáticas/inmunología , Células Plasmáticas/metabolismo , Receptor Toll-Like 9/metabolismoRESUMEN
The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum (T. pallidum) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss-of-function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red-shifted green fluorescent protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy- and cell sorting-based applications for T. pallidum, better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes.
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Hijacking the ubiquitin proteasome system to elicit targeted protein degradation (TPD) has emerged as a promising therapeutic strategy to target and destroy intracellular proteins at the post-translational level. Small molecule-based TPD approaches, such as proteolysis-targeting chimeras (PROTACs) and molecular glues, have shown potential, with several agents currently in clinical trials. Biological PROTACs (bioPROTACs), which are engineered fusion proteins comprised of a target-binding domain and an E3 ubiquitin ligase, have emerged as a complementary approach for TPD. Here, we describe a new method for the evolution and design of bioPROTACs. Specifically, engineered binding scaffolds based on the third fibronectin type III domain of human tenascin-C (Tn3) were installed into the E3 ligase tripartite motif containing-21 (TRIM21) to redirect its degradation specificity. This was achieved via selection of naïve yeast-displayed Tn3 libraries against two different oncogenic proteins associated with B-cell lymphomas, mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) and embryonic ectoderm development protein (EED), and replacing the native substrate-binding domain of TRIM21 with our evolved Tn3 domains. The resulting TRIM21-Tn3 fusion proteins retained the binding properties of the Tn3 as well as the E3 ligase activity of TRIM21. Moreover, we demonstrated that TRIM21-Tn3 fusion proteins efficiently degraded their respective target proteins through the ubiquitin proteasome system in cellular models. We explored the effects of binding domain avidity and E3 ligase utilization to gain insight into the requirements for effective bioPROTAC design. Overall, this study presents a versatile engineering approach that could be used to design and engineer TRIM21-based bioPROTACs against therapeutic targets.
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Complejo de la Endopetidasa Proteasomal , Proteínas , Humanos , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteolisis , Ubiquitinación , Ubiquitina/metabolismoRESUMEN
Methamphetamine (Meth) abuse and human immunodeficiency virus type 1 (HIV-1) infection are two major public health problems worldwide. Being frequently comorbid with HIV-1 infection, Meth abuse exacerbates neurocognitive impairment in HIV-1-infected individuals even in the era of combined antiretroviral therapy. While a large body of research have studied the individual effects of Meth and HIV-1 envelope glycoprotein 120 (gp120) in the brain, far less has focused on their synergistic influence. Moreover, it is well-documented that the hippocampus is the primary site of spatial learning and long-term memory formation. Dysregulation of activity-dependent synaptic transmission and plasticity in the hippocampus is believed to impair neurocognitive function. To uncover the underlying mechanisms for increased incidence and severity of HIV-1-associated neurocognitive disorders (HAND) in HIV-1-infected patients with Meth abuse, we investigated acute individual and combined effects of Meth (20 µM) and gp120 (200 pM) on synaptic transmission and plasticity in the CA1 region of young adult male rat hippocampus, a brain region known to be vulnerable to HIV-1 infection. Our results showed that acute localized application of Meth and gp120 each alone onto the CA1 region reduced short-term dynamics of input-output responses and frequency facilitation, and attenuated long-term potentiation (LTP) induced by either high frequency stimulation or theta burst stimulation. A synergistic augmentation on activity-dependent synaptic plasticity was observed when Meth and gp120 were applied in combination. Paired-pulse facilitation results exhibited an altered facilitation ratio, suggesting a presynaptic site of action. Further studies revealed an involvement of microglia NLRP3 inflammasome activation in Meth augmentation of gp120-mediated attenuation of LTP. Taken together, our results demonstrated Meth augmented gp120 attenuation of LTP in the hippocampus. Since LTP is the accepted experimental analog of learning at the synaptic level, such augmentation may underlie Meth exacerbation of HAND observed clinically.
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Infecciones por VIH , VIH-1 , Metanfetamina , Animales , Glicoproteínas/farmacología , Infecciones por VIH/complicaciones , Hipocampo , Humanos , Potenciación a Largo Plazo/fisiología , Masculino , Metanfetamina/farmacología , Trastornos Neurocognitivos , Plasticidad Neuronal , Ratas , Transmisión SinápticaAsunto(s)
Antibacterianos , Azitromicina , Farmacorresistencia Bacteriana , Macrólidos , Sífilis , Treponema pallidum , Humanos , Antibacterianos/farmacología , Antibacterianos/provisión & distribución , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/genética , Macrólidos/farmacología , Macrólidos/uso terapéutico , América del Norte , Sífilis/tratamiento farmacológico , Sífilis/genética , Sífilis/microbiología , Treponema pallidum/efectos de los fármacos , Treponema pallidum/genética , Treponema pallidum/aislamiento & purificación , Azitromicina/farmacología , Azitromicina/uso terapéutico , Estados Unidos , Canadá , Penicilina G Benzatina/farmacología , Penicilina G Benzatina/provisión & distribución , Penicilina G Benzatina/uso terapéutico , Doxiciclina/farmacología , Doxiciclina/provisión & distribución , Doxiciclina/uso terapéuticoRESUMEN
BACKGROUND: Frailty in older people is associated with increased risk of falls, longer length of stay in hospital, increased risk of institutionalisation and death. Frailty can be measured using validated tools. Multi-component frailty interventions are recommended in clinical practice guidelines but are not routinely implemented in clinical practice. METHODS: The Frailty in Older people: Rehabilitation, Treatment, Research Examining Separate Settings (FORTRESS) trial is a multisite, hybrid type II, stepped wedge, cluster, randomised trial with blinded assessment and intention-to-treat analysis being conducted in Australia. The study aims to determine the effectiveness and cost-effectiveness of an embedded individualised multicomponent frailty intervention (commencing in hospital and continuing in the community) on readmissions, frailty and quality of life when compared with usual care. Frail older people admitted to study wards with no significant cognitive impairment, who are expected to return home after discharge, will be eligible to participate. Participants will receive extra sessions of physiotherapy, pharmacy, and dietetics during their admission. A Community Implementation Facilitator will coordinate implementation of the frailty management strategies and primary network liaison. The primary outcome is number of days of non-elective hospital readmissions during 12 month follow-up period. Secondary outcomes include frailty status measured using the FRAIL scale; quality of life measured using the EQ-5D-5L; and time-to-event for readmission and readmission rates. The total cost of delivering the intervention will be assessed, and cost-effectiveness analyses will be conducted. Economic evaluation will include analyses for health outcomes measured in terms of the main clinical outcomes. Implementation outcomes will be collected as part of a process evaluation. Recruitment commenced in 2020 and we are aiming to recruit 732 participants over the three-year duration of the study. DISCUSSION: This study will reveal whether intervening with frail older people to address factors contributing to frailty can reduce hospital readmissions and improve frailty status and quality of life. If the FORTRESS intervention provides a clinically significant and cost-effective result, it will demonstrate an improved approach to treating frail patients, both in hospital and when they return home. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12620000760976p . ANZCTR registered 24 July 2020.
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Fragilidad , Accidentes por Caídas , Anciano , Australia/epidemiología , Fragilidad/diagnóstico , Fragilidad/terapia , Hospitalización , Humanos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
We have investigated a distinct disorder with progressive corneal neovascularization, keloid formation, chronic skin ulcers, wasting of subcutaneous tissue, flexion contractures of the fingers, and acro-osteolysis. In six affected individuals from four families, we found one of two recurrent variants in discoidin domain receptor tyrosine kinase 2 (DDR2): c.1829T>C (p.Leu610Pro) or c.2219A>G (p.Tyr740Cys). DDR2 encodes a collagen-responsive receptor tyrosine kinase that regulates connective-tissue formation. In three of the families, affected individuals comprise singleton adult individuals, and parental samples were not available for verification of the de novo occurrence of the DDR2 variants. In the fourth family, a mother and two of her children were affected, and the c.2219A>G missense variant was proven to be de novo in the mother. Phosphorylation of DDR2 was increased in fibroblasts from affected individuals, suggesting reduced receptor autoinhibition and ligand-independent kinase activation. Evidence for activation of other growth-regulatory signaling pathways was not found. Finally, we found that the protein kinase inhibitor dasatinib prevented DDR2 autophosphorylation in fibroblasts, suggesting an approach to treatment. We propose this progressive, fibrotic condition should be designated as Warburg-Cinotti syndrome.
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Enfermedades del Tejido Conjuntivo/genética , Receptor con Dominio Discoidina 2/genética , Adulto , Secuencia de Aminoácidos , Niño , Preescolar , Colágeno/genética , Enfermedades del Tejido Conjuntivo/tratamiento farmacológico , Femenino , Fibroblastos/efectos de los fármacos , Humanos , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas Receptoras/genética , Alineación de Secuencia , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genéticaRESUMEN
INTRODUCTION: Laser interstitial thermal therapy (LITT) is a minimally invasive treatment method in managing primary brain neoplasms, brain metastases, radiation necrosis, and epileptogenic lesions, many of which are located in operative corridors that would be difficult to address. Although the use of lasers is not a new concept in neurosurgery, advances in technology have enabled surgeons to perform laser treatment with the aid of real-time MRI thermography as a guide. In this report, we present our institutional series and outcomes of patients treated with LITT. METHODS: We retrospectively evaluated 19 patients (age range, 28-77 years) who underwent LITT at one or more targets from 2015 to 2019. Primary endpoint observed was mean progression free survival (PFS) and overall survival (OS). RESULTS: Seven patients with glial neoplasms and 12 patients with metastatic disease were reviewed. Average hospitalization was 2.4 days. Median PFS was 7 and 4 months in the metastatic group and primary glial neoplasm group, respectively (p = 0.01). Median OS from time of diagnosis was 41 and 32 months (p = 0.02) and median OS after LITT therapy was 25 and 24 months (p = 0.02) for the metastatic and primary glial neoplasm groups, respectively. One patient experienced immediate post-procedural morbidity secondary to increased intracerebral edema peri-lesionally while one patient experienced post-operative mortality and expired secondary to hemorrhage 1-month post-procedure. Median follow-up was 10 months. CONCLUSION: Laser interstitial thermal therapy (LITT) is a safe, minimally invasive treatment method that provides surgeons with cytoreductive techniques to treat neurosurgical conditions. Both PFS and OS appear to be more favorable after LITT in patients with metastatic disease. In properly selected patients, this modality offers improved survival outcomes in conjunction with other salvage therapies.
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Pathways of human epidermal growth factor (EGF) receptors are activated upon ligand-dependent or -independent homo- or heterodimerization and their subsequent transphosphorylation. Overexpression of these receptors positively correlates with transphosphorylation rates and increased tumor growth rates. MEDI4276, an anti-human epidermal growth factor receptor 2 (HER2) biparatopic antibody-drug conjugate, has two paratopes within each antibody arm. One, 39S, is aiming at the HER2 site involved in receptor dimerization and the second, single chain fragment (scFv), mimicking trastuzumab. Here we present the cocrystal structure of the 39S Fab-HER2 complex and, along with biophysical and functional assays, determine the corresponding epitope of MEDI4276 and its underlying mechanism of action. Our results reveal that MEDI4276's uniqueness is based first on the ability of its 39S paratope to block HER2 homo- or heterodimerization and second on its ability to cluster the receptors on the surface of receptor-overexpressing cells.
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Anticuerpos Monoclonales Humanizados/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Multimerización de Proteína , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Trastuzumab/farmacología , Secuencia de Aminoácidos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cristalografía por Rayos X , Femenino , Humanos , Modelos Moleculares , Fosforilación , Conformación Proteica , Homología de Secuencia , Células Tumorales CultivadasRESUMEN
Soluble ligands have commonly been targeted by antibody therapeutics for cancers and other diseases. Although monoclonal antibodies targeting such ligands can block their interactions with their cognate receptors, they can also significantly increase the half-life of their ligands by FcRn-mediated antibody recycling, thereby evading ligand renal clearance and requiring increasingly high antibody doses to neutralize the increasing pool of target. To overcome this issue, we generated a bispecific/biparatopic antibody (BiSAb) that targets two different epitopes on IL-6 to block IL-6-mediated signaling. The BiSAb formed large immune complexes with IL-6 that can bind Fcγ receptors on phagocytic cells and are rapidly internalized. In addition, rapid clearance of the BiSAb·IL-6 complex was observed in mice while the parental antibodies prolonged the serum half-life of IL-6. Intravital imaging of the liver in mice confirmed that the rapid clearance of these large immune complexes was associated with Fcγ receptor-dependent binding to Kupffer cells in the liver. The approach described here provides a general strategy for therapeutic antibodies with the ability to not only neutralize but also actively drive clearance of their soluble antigens.
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Anticuerpos Biespecíficos/metabolismo , Anticuerpos Monoclonales/metabolismo , Complejo Antígeno-Anticuerpo/inmunología , Interleucina-6/antagonistas & inhibidores , Receptores de IgG/metabolismo , Animales , Anticuerpos Biespecíficos/inmunología , Anticuerpos Monoclonales/inmunología , Células HEK293 , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Interleucina-6/inmunología , Macrófagos del Hígado/citología , Macrófagos del Hígado/metabolismo , Hígado/citología , Hígado/metabolismo , Ratones , Unión Proteica , Receptores de IgG/inmunologíaRESUMEN
OBJECTIVE: Children with neural tube defects (NTDs) require timely surgical intervention coupled with long-term management by multiple highly trained specialty healthcare teams. In resource-limited settings, outcomes are greatly affected by the lack of coordinated care. The purpose of this study was to characterize outcomes of spina bifida patients treated at Mulago National Referral Hospital (MNRH) through follow-up phone surveys. METHODS: All children presenting to MNRH with NTDs between January 1, 2014, and August 31, 2015, were eligible for this study. For those with a documented telephone number, follow-up phone surveys were conducted with the children's caregivers to assess mortality, morbidity, follow-up healthcare, and access to medical resources. RESULTS: Of the 201 patients, the vast majority (n = 185, 92%) were diagnosed with myelomeningocele. The median age at presentation was 6 days, the median length of stay was 20 days, and the median time to surgery was 10 days. Half of the patients had documented surgeries, with 5% receiving multiple procedures (n = 102, 51%): 80 defect closures (40%), 32 ventriculoperitoneal shunts (15%), and 1 endoscopic third ventriculostomy (0.5%). Phone surveys were completed for 53 patients with a median time to follow-up of 1.5 years. There were no statistically significant differences in demographics between the surveyed and nonrespondent groups. The 1-year mortality rate was 34% (n = 18). At the time of survey, 91% of the survivors (n = 30) have received healthcare since their initial discharge from MNRH, with 67% (n = 22) returning to MNRH. Hydrocephalus was diagnosed in 29 patients (88%). Caregivers reported physical deficits in 39% of patients (n = 13), clubfoot in 18% (n = 6), and bowel or bladder incontinence in 12% (n = 4). The surgical complication rate was 2.5%. Glasgow Outcome Scale-Extended pediatric revision scores were correlated with upper good recovery in 58% (n = 19) of patients, lower good recovery in 30% (n = 10), and moderate disability in 12% of patients (n = 4). Only 5 patients (15%) reported access to home health resources postdischarge. CONCLUSIONS: This study is the first to characterize the outcomes of children with NTDs that were treated at Uganda's national referral hospital. There is a great need for improved access to and coordination of care in antenatal, perioperative, and long-term settings to improve morbidity and mortality.
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Defectos del Tubo Neural/cirugía , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Hidrocefalia/etiología , Lactante , Recién Nacido , Tiempo de Internación , Masculino , Meningomielocele/cirugía , Defectos del Tubo Neural/complicaciones , Defectos del Tubo Neural/mortalidad , Manejo de Atención al Paciente , Derivación y Consulta , Centros de Atención Terciaria , UgandaRESUMEN
Anaphylatoxin C5a released upon complement activation is associated with both acute and chronic inflammations such as gout. The pathogenesis of gout was identified as uric acid crystal deposition in the joints that activates inflammasome, leading to IL-1ß release. However, little is known about the interaction between complement activation and monosodium urate/uric acid (MSU) crystal-induced inflammasome activation or IL-1ß production. Here, we report that MSU crystal-induced proinflammatory cytokines/chemokines in human whole blood is predominantly regulated by C5a through its interaction with C5a receptor. C5a induces pro-IL-1ß and IL-1ß production in human primary monocytes, and potentiates MSU or cholesterol crystals in IL-1ß production. This potentiation is caspase-1 dependent and requires intracellular Ca(2+) mobilization, K(+) efflux, and cathepsin B activity. Our results provide insight into the role of C5a as an endogenous priming signal that is required for the initiation of uric acid crystal-induced IL-1ß production. C5a could potentially be a therapeutic target together with IL-1ß antagonists for the treatment of complement-dependent and inflammasome-associated diseases.
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Antioxidantes/farmacología , Señalización del Calcio/efectos de los fármacos , Complemento C5a/inmunología , Interleucina-1beta/inmunología , Monocitos/inmunología , Ácido Úrico/farmacología , Antioxidantes/efectos adversos , Calcio/inmunología , Señalización del Calcio/inmunología , Caspasa 1/inmunología , Femenino , Humanos , Inflamasomas/inmunología , Masculino , Monocitos/patología , Potasio/inmunología , Ácido Úrico/efectos adversosRESUMEN
Targeting Eph (erythropoietin producing hepatoma) receptors with monoclonal antibodies is being explored as therapy for several types of cancer. To test whether simultaneous targeting of EphA2, EphA4, and EphB4 would be an effective approach to cancer therapy, we generated a recombinant trispecific antibody using the variable domain genes of anti-EphA2, anti-EphA4, and anti-EphB4 monoclonal antibodies. A multidisciplinary approach combining biochemical, biophysical, and cellular-based assays was used to characterize the trispecific antibody in vitro and in vivo. Here we demonstrate that the trispecific antibody is expressed at high levels by mammalian cells, monodispersed in solution, thermostable, capable of simultaneously binding the three receptors, and able to activate the three targets effectively as evidenced by receptor internalization and degradation both in vitro and in vivo. Furthermore, pharmacokinetic analysis using tumor-bearing nude mice showed that the trispecific antibody remains in the circulation similarly to its respective parental antibodies. These results indicate that simultaneous blockade of EphA2, EphA4, and EphB4 could be an attractive approach to cancer therapy.
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Anticuerpos Monoclonales/farmacología , Antígenos/inmunología , Diseño de Fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Receptor EphA2/antagonistas & inhibidores , Receptor EphA4/antagonistas & inhibidores , Receptor EphB4/antagonistas & inhibidores , Animales , Rastreo Diferencial de Calorimetría , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Masculino , Ratones , Ratones Desnudos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Unión Proteica , Receptor EphA2/inmunología , Receptor EphA4/inmunología , Receptor EphB4/inmunología , Resonancia por Plasmón de Superficie , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
There is a clinical need for more accurate diagnosis and prognostication in patients with disorders of consciousness (DoC). There are several neuroimaging modalities that enable detailed, quantitative assessment of structural and functional brain injury, with demonstrated diagnostic and prognostic value. Additionally, longitudinal neuroimaging studies have hinted at quantifiable structural and functional neuroimaging biomarkers of recovery, with potential implications for the management of DoC.
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Encéfalo , Imagen por Resonancia Magnética , Humanos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Trastornos de la Conciencia/diagnóstico por imagen , Neuroimagen/métodos , Estado de ConcienciaRESUMEN
The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum ( T. pallidum ) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss-of-function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red-shifted Green Fluorescent Protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy- and cell sorting-based applications for T. pallidum , better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes. Graphical abstract: By employing genetic engineering, T. pallidum was modified to express GFP, and Sf1Ep cells to express mCherry on the cytoplasmic membrane and BFP in the nucleus. These new resources for syphilis research will facilitate experimental designs to better define the complex interplay between T. pallidum and the host during infection.
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Purpose: Metastatic castration-resistant prostate cancer remains incurable regardless of recent therapeutic advances. Prostate cancer tumors display highly glycolytic phenotypes as the cancer progresses. Non-specific inhibitors of glycolysis have not been utilized successfully for chemotherapy, because of their penchant to cause systemic toxicity. This study reports the preclinical activity, safety, and pharmacokinetics of a novel small molecule preclinical candidate, BKIDC-1553, with antiglycolytic activity. Experimental design: We tested a large battery of prostate cancer cell lines for inhibition of cell proliferation, in vitro. Cell cycle, metabolic and enzymatic assays were used to demonstrate their mechanism of action. A human PDX model implanted in mice and a human organoid were studied for sensitivity to our BKIDC preclinical candidate. A battery of pharmacokinetic experiments, absorption, distribution, metabolism, and excretion experiments, and in vitro and in vivo toxicology experiments were carried out to assess readiness for clinical trials. Results: We demonstrate a new class of small molecule inhibitors where antiglycolytic activity in prostate cancer cell lines is mediated through inhibition of hexokinase 2. These compounds display selective growth inhibition across multiple prostate cancer models. We describe a lead BKIDC-1553 that demonstrates promising activity in a preclinical xenograft model of advanced prostate cancer, equivalent to that of enzalutamide. BKIDC-1553 demonstrates safety and pharmacologic properties consistent with a compound that can be taken into human studies with expectations of a good safety margin and predicted dosing for efficacy. Conclusion: This work supports testing BKIDC-1553 and its derivatives in clinical trials for patients with advanced prostate cancer.
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Metastatic castration-resistant prostate cancer remains incurable regardless of recent therapeutic advances. Prostate cancer tumors display highly glycolytic phenotypes as the cancer progresses. Nonspecific inhibitors of glycolysis have not been utilized successfully for chemotherapy, because of their penchant to cause systemic toxicity. This study reports the preclinical activity, safety, and pharmacokinetics of a novel small-molecule preclinical candidate, BKIDC-1553, with antiglycolytic activity. We tested a large battery of prostate cancer cell lines for inhibition of cell proliferation, in vitro. Cell-cycle, metabolic, and enzymatic assays were used to demonstrate their mechanism of action. A human patient-derived xenograft model implanted in mice and a human organoid were studied for sensitivity to our BKIDC preclinical candidate. A battery of pharmacokinetic experiments, absorption, distribution, metabolism, and excretion experiments, and in vitro and in vivo toxicology experiments were carried out to assess readiness for clinical trials. We demonstrate a new class of small-molecule inhibitors where antiglycolytic activity in prostate cancer cell lines is mediated through inhibition of hexokinase 2. These compounds display selective growth inhibition across multiple prostate cancer models. We describe a lead BKIDC-1553 that demonstrates promising activity in a preclinical xenograft model of advanced prostate cancer, equivalent to that of enzalutamide. BKIDC-1553 demonstrates safety and pharmacologic properties consistent with a compound that can be taken into human studies with expectations of a good safety margin and predicted dosing for efficacy. This work supports testing BKIDC-1553 and its derivatives in clinical trials for patients with advanced prostate cancer.
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Proliferación Celular , Glucólisis , Ensayos Antitumor por Modelo de Xenoinjerto , Masculino , Humanos , Animales , Ratones , Glucólisis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéuticoRESUMEN
The location and distribution of glioblastoma (GBM) within the brain parenchyma plays an important role in surgical and radiation planning. Prior studies have reported incidences of multiple lesions at the time of diagnosis ranging from 0.5 to 20 %. Multiple lesions can be further categorized as multifocal (multiple areas involved, but with a clear path of spread from one lesion to another) or multicentric (multiple lesions, no clear path of spread). In this retrospective study, we reviewed our experience with GBM and found the incidence of multiple lesions at time of diagnosis was 35 %, much higher than previously suggested in the literature. Patients with single lesions had an improved overall survival when compared to patients with multiple lesions (18 vs. 10 months). Patients with multicentric lesions fared the worst, with average survival of 3 months. However, the difference between single and multiple lesions (multifocal or multicentric) was no longer significant when taking into consideration age, Karnofsky performance score (KPS) and extent of resection by multivariate analysis. Age, KPS, gross total resection, and MGMT status were independent predictors of outcome. Multiple lesions did not independently confer a worse outcome, but were associated with lower KPS scores and inability to perform gross total resection. These findings suggest that single, multiple and multicentric imaging exams represent a spectrum of presentations of a single disease. The rate of multiple lesions reported here may be the result of improved imaging technology, suggesting that incidence of multiple lesions will continue to increase as imaging technology advances.
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Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/patología , Encéfalo/patología , Glioblastoma/epidemiología , Glioblastoma/patología , Neoplasias Encefálicas/mortalidad , Femenino , Glioblastoma/mortalidad , Humanos , Incidencia , Estimación de Kaplan-Meier , Estado de Ejecución de Karnofsky , Imagen por Resonancia Magnética , MasculinoRESUMEN
Fructose-1,6-bisphosphatase (FBPase), a key enzyme of gluconeogenesis and photosynthetic CO(2) fixation, catalyzes the hydrolysis of fructose 1,6-bisphosphate (FBP) to produce fructose 6-phosphate, an important precursor in various biosynthetic pathways. All known FBPases are metal-dependent enzymes, which are classified into five different classes based on their amino acid sequences. Eukaryotes are known to contain only the type-I FBPases, whereas all five types exist in various combinations in prokaryotes. Here we demonstrate that the uncharacterized protein YK23 from Saccharomyces cerevisiae efficiently hydrolyzes FBP in a metal-independent reaction. YK23 is a member of the histidine phosphatase (phosphoglyceromutase) superfamily with homologues found in all organisms. The crystal structure of the YK23 apo-form was solved at 1.75-A resolution and revealed the core domain with the alpha/beta/alpha-fold covered by two small cap domains. Two liganded structures of this protein show the presence of two phosphate molecules (an inhibitor) or FBP (a substrate) bound to the active site. FBP is bound in its linear, open conformation with the cleavable C1-phosphate positioned deep in the active site. Alanine replacement mutagenesis of YK23 identified six conserved residues absolutely required for activity and suggested that His(13) and Glu(99) are the primary catalytic residues. Thus, YK23 represents the first family of metal-independent FBPases and a second FBPase family in eukaryotes.
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Fructosa-Bifosfatasa/química , Fructosa-Bifosfatasa/metabolismo , Saccharomyces cerevisiae/enzimología , Secuencia de Aminoácidos , Clonación Molecular , Cristalografía por Rayos X , Fructosa-Bifosfatasa/genética , Fructosadifosfatos/metabolismo , Amplificación de Genes , Regulación de la Expresión Génica , Hidrólisis , Cinética , Magnesio/farmacología , Manganeso/farmacología , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Conformación Proteica , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad por SustratoRESUMEN
Stool descriptors have become popular due to the large diffusion of the Bristol Stool Form Scale (BSFS) via clinical studies, clinical trials, and social media. The applications have been numerous and centered around standardization of terminology that can be used by health care professionals and patients alike, as well as individuals interested in their wellness and the associated partners in the wellness industry. For a portion of the population, the digestive content is rerouted to an external manufactured pouch or bag, making the use of the BSFS visual descriptors of stool difficult. From day one post-resection surgery, ostomates are challenged with output management. The lack of standardized descriptors may hinder proper communication between the individual and the support team, as well as providing proper characterization in clinical studies and clinical trials. We propose the Lincoln Ostomy Output Consistency Scale for jejunostomy, ileostomy and colostomy (LOOCS) to overcome the limitations of the BSFS for qualifying ostomy outputs. The design was based on the need to describe perceived consistency from the ostomate point of view. We anticipate that the LOOCS scale can be effective in pediatric and adult clinical research settings, as well as self-monitoring to manage the quality of life.