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Interfacial solar evaporation (ISE) holds considerable promise to solve fresh water shortage, but it is challenging to achieve high evaporation rate (Reva) and fresh water yield in close system. Here, we report design and preparation of MOF-based solar evaporators with hierarchical microporous/nanobridged/nanogranular structures for rapid ISE and fresh water collection in close system. The evaporators are fabricated by growing silicone nanofilaments with variable length as nanobridges on a microporous silicone sponge followed by grafting with polydopamine nanoparticles and Cu-MOF nanocrystals. Integration of the unique structure and excellent photothermal composites endows the evaporators with high Reva of 3.5-20 wt% brines (3.60-2.90 kg m-2 h-1 in open system and 2.38-1.44 kg m-2 h-1 in close system) under simulated 1 sun, high Reva under natural sunlight, excellent salt resistance and high fresh water yield, which surpass most state-of-the-art evaporators. Moreover, when combined with a superhydrophilic cover, the evaporators show much higher average Reva of real seawater, remarkable fresh water yield and excellent long-term stability over one month continuous ISE under natural sunlight. The findings here will promote the development of advanced evaporators via microstructure engineering and their real-world ISE applications.
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Solitary fibrous tumor (SFT) is a rare spindle cell tumor originating from mesenchymal tissue, and even rarer when it occurs intracranially. This case report described a 42-year-old man who presented with headache and limb weakness for more than 10 days. Magnetic resonance imaging (MRI) showed a well-defined multicompartmental cystic space-occupying lesion in the left occipital region, with surrounding edema and a compressed left lateral ventricle, the mass growing across the cerebellar vermis, which was initially diagnosed as hemangioblastoma. Neurosurgery was utilized to successfully remove the mass, and intracranial solitary fibrous tumor (ISFT) was identified by postoperative pathological analysis. Here, this article describes the imaging manifestations and pathologic features of a case of cystic intracranial solitary fibrous tumor, aiming to improve the understanding and diagnosis of this disease in order to provide an accurate therapy plan.
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Circulating tumor cells (CTCs) captured from the bloodstream of patients with solid tumors have the potential to accelerate precision oncology by providing insight into tumor biology, disease progression and response to treatment. However, their potential is hampered by the lack of standardized CTC enrichment platforms across tumor types. EpCAM-based CTC enrichment, the most commonly used platform, is limited by EpCAM downregulation during metastasis and the low EpCAM expression in certain tumor types, including the highly prevalent and lethal NSCLC. In this study we demonstrate that Transferrin Receptor (TfR) is a selective, efficient biomarker for CTC identification and capture in patients with prostate, pancreatic and NSCLC. TfR identifies significantly higher CTC counts than EpCAM, and TfR + -CTC enumeration correlates with disease progression in metastatic prostate and pancreatic cancers, and overall survival and osimetrinib-resistance in non-small cell lung cancer (NSCLC). Profiling of TfR + -CTCs provides a snapshot of the molecular landscape of each respective tumor type and identifies potential mechanisms underlying treatment response to EGFR TKi and immune checkpoint inhibitors in NSCLC. One sentence summary: Transferrin Receptor identifies circulating tumor cells in solid tumors.
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Harvesting freshwater from fog is one of the possible solutions to the global water scarcity crisis. Surfaces with both hydrophobic and hydrophilic regions are extensively employed for this purpose. Nevertheless, the longevity of these surfaces is still constrained by their delicate surface structures. The hydrophilic zones may become damaged or contaminated after repeated use, thereby compromising their effectiveness in fog collection. The preparation of generally applicable durable superhydrophobic coatings with self-generated Wenzel sites is reported here for long-term efficient and stable fog collection. The coatings are prepared by depositing the poly(tannic acid) coating as the primer layer on various substrates, self-assembly of trichlorovinylsilane into staggered silicone nanofilaments, and then thiol-ene click reaction with 1H,1H,2H,2H-perfluorodecanethiol. The coatings demonstrate remarkable static superhydrophobicity, robust impalement resistance, and stable self-generated Wenzel sites for water droplets. Therefore, the fog collection rate (FCR) of the coatings reaches 2.13 g cm-2 h-1 during 192 h continuous fog collection, which is triple that of bare substrate and outperforms most previous studies. Moreover, the systematic experiments and models have revealed that the key factors for achieving high FCR on superhydrophobic coatings are forming condensed droplets ≈1 mm in critical radius and a Wenzel site proportion of 0.3-0.4.
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RESEARCH QUESTION: What is the effect of miR-122 on the progression and recovery of fibrosis in Asherman's syndrome? DESIGN: Endometrial tissue was collected from 21 patients, 11 with intrauterine adhesion (IUA) and 10 without IUA. Quantitative real-time polymerase chain reaction, immunofluorescence and Western blot were applied to observe the expression of mRNAs/miRNAs and protein, respectively. The endometrial physical injury was carried out in C57BL/6 mice to create an endometrial fibrosis model, with intrauterine injection of adenovirus to compare the antifibrosis and repair function of miR-122 on endometrium. The morphology of the uterus was observed using haematoxylin and eosin staining, and fibrosis markers were detected by immunohistochemistry. RESULTS: miR-122 expression was reduced in patients with IUAs, accompanied by fibrosis. MiR-122 overexpression reduced the degree of fibrosis in endometrial stromal cells. Further molecular analyses demonstrated that miR-122 inhibited fibrosis through the TGF-ß/SMAD pathway by directly targeting the 3' untranslated region of SMAD family member 3, suppressing its expression. Notably, miR-122 promoted endometrial regeneration and recovery of pregnancy capacity in a mouse endometrial injury model. CONCLUSIONS: miR-122 is a critical regulator for repair of endometrial fibrosis and provided new insight for the clinical treatment of intrauterine adhesions.
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Ginatresia , MicroARNs , Enfermedades Uterinas , Ratones , Animales , Femenino , Embarazo , Humanos , Factor de Crecimiento Transformador beta/metabolismo , Ratones Endogámicos C57BL , Enfermedades Uterinas/genética , Enfermedades Uterinas/patología , Endometrio/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Adherencias Tisulares , Modelos Animales de Enfermedad , FibrosisRESUMEN
Mucinous tubular and spindle cell carcinoma of the kidney (MTSCC) is a rare subtype of renal cancer. It consists of tubules separated by mucus stroma and a spindle cell. Few cases have been reported; thus, the imaging features of MTSCC are not well characterized. An MTSCC in the left kidney of a 65-year-old woman was incidentally discovered during a medical checkup. A review of the patient's medical history revealed that this kidney lump had an indolent growth process. The current study presented this case and reviewed the pathological features, imaging findings and treatment options of MTSCC to strengthen the recognition of this rare renal neoplasm by radiologists.
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Accessory spleen (AS) refers to single or multiple splenic tissues which appear outside the relative normal spleen position results from embryonic dysplasia similar in structure and function to the spleen. AS is frequently observed in the splenic hilus and or adjacent to the tail of pancreas, and only a few cases occurred in the pelvic cavity. We present an extremely rare AS case in urachus, which was initially considered as an urachal neoplasm revealed on CT images with big mass. However, the postoperative pathology confirmed it was an AS that had not been reported at urachal before. Urachal AS can be misdiagnosed as a tumor, so it is vital to make an accurate imaging preoperative diagnosis to avoid unnecessary biopsy and surgery.
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Uraco , Humanos , Uraco/diagnóstico por imagen , Uraco/cirugía , Bazo/diagnóstico por imagen , Bazo/cirugía , Tomografía Computarizada por Rayos X , BiopsiaRESUMEN
Ovarian collision tumors are uncommon and reports of their radiological appearance are even less frequent. The present study reported the world's first case of an ovarian collision tumor consisting of an ovarian sclerosing stromal tumor and a mature cystic teratoma and its imaging presentation. When a cystic solid ovarian mass combined with ascites and elevated CA125 is encountered it is frequently diagnosed as a malignant tumor, but the present case was a benign tumor. Therefore, when encountering similar cases, clinicians should not limit the diagnosis to malignant tumors to avoid rashly expanding the surgery and causing unnecessary harm to the patient. The combination of computed tomography, magnetic resonance imaging and pathology findings presented in the current study enable radiologists to learn about this disease and further assist clinicians in developing the best treatment plan.
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Schwannoma is a benign tumor that originates from Schwann cells in the peripheral nerve tunica or bundle of nerves and grows along the longitudinal axis of the nerve. Schwannoma can occur in multiple anatomic locations but rarely in the sciatic nerve. To our knowledge, there are no previous reports in the literature related to schwannoma combined with effusion of the nerve bundle membranes. Here, we report two cases of sciatic nerve schwannoma combined with nerve bundle membrane effusion, and the relationship between them is uncertain. We have boldly speculated about this uncertain relationship by combining the two patients' imaging manifestations to help determine the mechanism of schwannoma or effusion generation as well as a clinical treatment.
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Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) is a low-grade malignant tumor type caused by the proliferation of follicular dendritic cells. It is a distinct subtype of FDCS that is rarely encountered in the clinic and is overwhelmingly associated with Epstein-Barr virus infection. As it is a sporadic disease with a low specificity of clinical and imaging manifestations, it is less frequently considered a diagnosis, resulting in a low preoperative diagnostic rate and easy misdiagnosis. The present study reported the ultrasound, CT and MRI features of a patient with splenic IPT-like FDCS and discussed this rare subtype of FDCS based on a review of previously published literature to provide radiologists with a broader understanding of the differential diagnosis of splenic lesions.
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OBJECTIVE: STriatal-Enriched protein tyrosine Phosphatase (STEP) is a brain-specific tyrosine phosphatase. Membrane-bound STEP61 is the only isoform expressed in hippocampus and cortex. Genetic deletion of STEP enhances excitatory synaptic currents and long-term potentiation in the hippocampus. However, whether STEP61 affects seizure susceptibility is unclear. Here we investigated the effects of STEP inhibitor TC-2153 on seizure propensity in a murine model displaying kainic acid (KA)-induced status epilepticus and its effect on hippocampal excitability. METHODS: Adult male and female C57BL/6J mice received intraperitoneal injection of either vehicle (2.8% dimethylsulfoxide [DMSO] in saline) or TC-2153 (10 mg/kg) and then either saline or KA (30 mg/kg) 3 h later before being monitored for behavioral seizures. A subset of female mice was ovariectomized (OVX). Acute hippocampal slices from Thy1-GCaMP6s mice were treated with either DMSO or TC-2153 (10 µM) for 1 h, and then incubated in artificial cerebrospinal fluid (ACSF) and potassium chloride (15 mM) for 2 min prior to live calcium imaging. Pyramidal neurons in dissociated rat hippocampal culture (DIV 8-10) were pre-treated with DMSO or TC-2153 (10 µM) for 1 h before whole-cell patch-clamp recording. RESULTS: TC-2153 treatment significantly reduced KA-induced seizure severity, with greater trend seen in female mice. OVX abolished this TC-2153-induced decrease in seizure severity in female mice. TC-2153 application significantly decreased overall excitability of acute hippocampal slices from both sexes. Surprisingly, TC-2153 treatment hyperpolarized resting membrane potential and decreased firing rate, sag voltage, and hyperpolarization-induced current (Ih ) of cultured hippocampal pyramidal neurons. SIGNIFICANCE: This study is the first to demonstrate that pharmacological inhibition of STEP with TC-2153 decreases seizure severity and hippocampal activity in both sexes, and dampens hippocampal neuronal excitability and Ih . We propose that the antiseizure effects of TC-2153 are mediated by its unexpected action on suppressing neuronal intrinsic excitability.
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Dimetilsulfóxido , Hipocampo , Animales , Benzotiepinas , Dimetilsulfóxido/efectos adversos , Dimetilsulfóxido/metabolismo , Femenino , Ácido Kaínico/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Convulsiones/inducido químicamente , Convulsiones/metabolismoRESUMEN
Epileptic encephalopathy (EE) is characterized by seizures that respond poorly to antiseizure drugs, psychomotor delay, and cognitive and behavioral impairments. One of the frequently mutated genes in EE is KCNQ2, which encodes the Kv7.2 subunit of voltage-gated Kv7 potassium channels. Kv7 channels composed of Kv7.2 and Kv7.3 are enriched at the axonal surface, where they potently suppress neuronal excitability. Previously, we reported that the de novo dominant EE mutation M546V in human Kv7.2 blocks calmodulin binding to Kv7.2 and axonal surface expression of Kv7 channels via their intracellular retention. However, whether these pathogenic mechanisms underlie epileptic seizures and behavioral comorbidities remains unknown. Here, we report conditional transgenic cKcnq2+/M547V mice, in which expression of mouse Kv7.2-M547V (equivalent to human Kv7.2-M546V) is induced in forebrain excitatory pyramidal neurons and astrocytes. These mice display early mortality, spontaneous seizures, enhanced seizure susceptibility, memory impairment, and repetitive behaviors. Furthermore, hippocampal pathology shows widespread neurodegeneration and reactive astrocytes. This study demonstrates that the impairment in axonal surface expression of Kv7 channels is associated with epileptic seizures, cognitive and behavioral deficits, and neuronal loss in KCNQ2-related EE.
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Síndromes Epilépticos/genética , Canal de Potasio KCNQ2/genética , Proteínas del Tejido Nervioso/genética , Animales , Conducta Animal , Disfunción Cognitiva , Síndromes Epilépticos/patología , Síndromes Epilépticos/psicología , Femenino , Gliosis , Hipocampo/patología , Canal de Potasio KCNQ2/metabolismo , Ácido Kaínico , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas del Tejido Nervioso/metabolismo , Células Piramidales/metabolismoRESUMEN
Phosphatidylinositol-4,5-bisphosphate (PIP2) is a signaling lipid which regulates voltage-gated Kv7/KCNQ potassium channels. Altered PIP2 sensitivity of neuronal Kv7.2 channel is involved in KCNQ2 epileptic encephalopathy. However, the molecular action of PIP2 on Kv7.2 gating remains largely elusive. Here, we use molecular dynamics simulations and electrophysiology to characterize PIP2 binding sites in a human Kv7.2 channel. In the closed state, PIP2 localizes to the periphery of the voltage-sensing domain (VSD). In the open state, PIP2 binds to 4 distinct interfaces formed by the cytoplasmic ends of the VSD, the gate, intracellular helices A and B and their linkers. PIP2 binding induces bilayer-interacting conformation of helices A and B and the correlated motion of the VSD and the pore domain, whereas charge-neutralizing mutations block this coupling and reduce PIP2 sensitivity of Kv7.2 channels by disrupting PIP2 binding. These findings reveal the allosteric role of PIP2 in Kv7.2 channel activation.
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Canal de Potasio KCNQ2/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Sitios de Unión , Humanos , Simulación de Dinámica MolecularRESUMEN
Quantitation of androgen receptor variant (AR-V) expression in circulating tumor cells (CTCs) from patients with metastatic castration-resistant prostate cancer (mCRPC) has great potential for treatment customization. However, the absence of a uniform CTC isolation platform and consensus on an analytical assay has prevented the incorporation of these measurements in routine clinical practice. Here, we present a single-CTC sensitive digital droplet PCR (ddPCR) assay for the quantitation of the two most common AR-Vs, AR-V7, and AR-v567es, using antigen agnostic CTC enrichment. In a cohort of 29 mCRPC patients, we identify AR-V7 in 66% and AR-v567es in 52% of patients. These results are corroborated using another gene expression platform (NanoStringTM) and by analysis of RNA-Seq data from patients with mCRPC (SU2C- PCF Dream Team). We next quantify AR-V expression in matching EpCAM-positive vs EpCAM-negative CTCs, as EpCAM-based CTC enrichment is commonly used. We identify lower AR-V prevalence in the EpCAM-positive fraction, suggesting that EpCAM-based CTC enrichment likely underestimates AR-V prevalence. Lastly, using single CTC analysis we identify enrichment for AR-v567es in patients with neuroendocrine prostate cancer (NEPC) indicating that AR-v567es may be involved in lineage plasticity, which warrants further mechanistic interrogation.
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Células Neoplásicas Circulantes/química , Neoplasias de la Próstata/patología , Receptores Androgénicos/genética , Línea Celular Tumoral , Humanos , Masculino , Estadificación de Neoplasias , Neoplasias de la Próstata/química , RNA-Seq , Receptores Androgénicos/análisis , Receptores Androgénicos/fisiologíaRESUMEN
BACKGROUND: The amino acid sequence of proteins generally carries all the necessary information for acquisition of native conformations, but the vectorial nature of translation can additionally determine the folding outcome. Such consideration is particularly relevant in human diseases associated to inherited mutations leading to structural instability, aggregation, and degradation. Mutations in the KCNQ2 gene associated with human epilepsy have been suggested to cause misfolding of the encoded Kv7.2 channel. Although the effect on folding of mutations in some domains has been studied, little is known of the way pathogenic variants located in the calcium responsive domain (CRD) affect folding. Here, we explore how a Kv7.2 mutation (W344R) located in helix A of the CRD and associated with hereditary epilepsy interferes with channel function. RESULTS: We report that the epilepsy W344R mutation within the IQ motif of CRD decreases channel function, but contrary to other mutations at this site, it does not impair the interaction with Calmodulin (CaM) in vitro, as monitored by multiple in vitro binding assays. We find negligible impact of the mutation on the structure of the complex by molecular dynamic computations. In silico studies revealed two orientations of the side chain, which are differentially populated by WT and W344R variants. Binding to CaM is impaired when the mutated protein is produced in cellulo but not in vitro, suggesting that this mutation impedes proper folding during translation within the cell by forcing the nascent chain to follow a folding route that leads to a non-native configuration, and thereby generating non-functional ion channels that fail to traffic to proper neuronal compartments. CONCLUSIONS: Our data suggest that the key pathogenic mechanism of Kv7.2 W344R mutation involves the failure to adopt a configuration that can be recognized by CaM in vivo but not in vitro.
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Epilepsia , Canal de Potasio KCNQ2/genética , Secuencia de Aminoácidos , Calcio/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Epilepsia/genética , Humanos , Canal de Potasio KCNQ2/metabolismo , MutaciónRESUMEN
ABSTRACT: This study investigates the effect of 2 laparoscopic methods on ovarian reserve in patients of reproductive age with endometriomas.This was a retrospective study performed at a tertiary medical center from Jan 1st to Dec 31st, 2016. Laparoscopic cystectomy (group 1, 46 patients) and laparoscopic ovarian drainage and ablation with bipolar coagulation at low power (group 2, 30 patients) were performed to treat endometriomas larger than 3âcm. Anti-Müllerian hormone was used to assess ovarian reserve before and after surgery.There were no statistically significant differences in patients' baseline clinical characteristics, endometriotic stage, operative time, and follow-up time between the groups. The mean serum anti-Müllerian hormone concentration decreased significantly from 4.25âng/ml to 3.40âng/ml in group 1 compared with 4.47âng/ml to 3.95âng/ml in group 2 (Pâ =â.04). Pregnancy rates were 71.05% in group 1 and 73.08% in group 2, with a mean follow-up of 30.40âmonths and 32.35âmonths (Pâ >â.99), respectively. Although there was no statistical significance, the recurrence rate in group 1 was lower than that in group 2 (4.35% vs 16.67%, respectively; Pâ=â.11). The mean diameter of recurrent cysts was 1.75âcm in group 1 and 1.54âcm in group 2 (Pâ=â.13).Appropriate laparoscopic electrocautery of the endometrioma wall with a bipolar instrument may be a valid alternative to traditional laparoscopic cystectomy, with less effects on ovarian reserve.
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Quistes/cirugía , Técnicas de Ablación Endometrial/métodos , Endometriosis/cirugía , Laparoscopía/métodos , Reserva Ovárica , Adulto , Hormona Antimülleriana/sangre , Quistes/patología , Endometriosis/patología , Femenino , Humanos , Embarazo , Estudios RetrospectivosRESUMEN
Objective: To explore the dynamic features of intrinsic brain activity measured by fMRI in children with benign epilepsy with centrotemporal spikes (BECTS) and examine whether these indexes were associated with behaviors. Methods: We recruited 26 children with BECTS (10.35 ± 2.91 years) and 26 sex-, and age-matched (11.35 ± 2.51 years) healthy controls (HC) and acquired resting-state functional magnetic resonance imaging (rs-fMRI) and behavioral data. Dynamic regional homogeneity (dReHo), including mean and coefficient of variation (CV) metrics derived from the rs-fMRI data, and were compared between the BECTS and the HC groups. Results: Significantly decreased mean dReHo in bilateral supramarginal gyrus, left middle temporal gyrus (MTG.L), left postcentral gyrus and superior occipital gyrus were found in children with BECTS. Meanwhile, increased CV of dReHo in MTG.L and right fusiform in children with BECTS was revealed compared with HC. Further analyses of functional connectivity revealed decreased global signal FC existed in similar regions, linked with linguistic, social cognition, and sensorimotor processes, in children with BECTS compared with HCs. Moreover, the association analyses showed that the CV of dReHo in MTG.L was positively associated with age and a negative correlation was found between mean dReHo of MTG.L and disease duration. Besides, the CV of dReHo in MTG.L was found positively associated with the intelligence quotient (IQ) language scores and full IQ scores in children with BECTS, and the CV of dReHo in the left inferior temporal gyrus and Rolandic operculum were positively correlated with IQ operation scores and full IQ scores. Conclusion: Aberrant dynamic regional coherence in sensorimotor, linguistic, and lateral temporal regions suggests dynamical interplay that underlying cognitive performance in children with BECTS, suggesting an intrinsic dynamic mechanism for BECTS.
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Activity-dependent persistent changes in neuronal intrinsic excitability and synaptic strength are widely thought to underlie learning and memory. Voltage-gated KCNQ/Kv7 potassium channels have been of great interest as the potential targets for memory disorders due to the beneficial effects of their antagonists in cognition. Importantly, de novo dominant mutations in their neuronal subunits KCNQ2/Kv7.2 and KCNQ3/Kv7.3 are associated with epilepsy and neurodevelopmental disorder characterized by developmental delay and intellectual disability. The role of Kv7 channels in neuronal excitability and epilepsy has been extensively studied. However, their functional significance in neural plasticity, learning, and memory remains largely unknown. Here, we review recent studies that support the emerging roles of Kv7 channels in intrinsic and synaptic plasticity, and their contributions to cognition and behavior.
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PURPOSE: Although taxane-based therapy is standard treatment for advanced gastric cancer, a majority of patients exhibit intrinsic resistance to taxanes. Here, we aim to identify the molecular basis of taxane resistance in gastric cancer. EXPERIMENTAL DESIGN: We performed a post hoc analysis of the TAX-325 clinical trial and molecular interrogation of gastric cancer cell lines to assess the benefit of docetaxel in diffuse (DIF-GC) versus intestinal (INT-GC) gastric cancer. We assessed drug-induced microtubule stabilization in gastric cancer cells and in biopsies of patients with gastric cancer treated with taxanes. We performed transcriptome analysis in taxane-treated gastric cancer cells and patients to identify molecular drivers of taxane resistance. RESULTS: Patients with DIF-GC did not derive a clinical benefit from taxane treatment suggesting intrinsic taxane resistance. DIF-GC cell lines displayed intrinsic resistance specific to taxanes because of impaired drug-induced microtubule stabilization, in the absence of tubulin mutations or decreased drug accumulation. Using taxane-treated gastric cancer patient biopsies, we demonstrated that absence of drug-target engagement was correlated with clinical taxane resistance. Taxane-sensitive cell lines displayed faster microtubule dynamics at baseline, implicating proteins that regulate cytoskeletal dynamics in intrinsic taxane resistance. Differential gene expression analysis of untreated and docetaxel-treated gastric cancer lines and patient samples identified kinesins to be associated with taxane sensitivity in vitro and in patient samples. CONCLUSIONS: Our data reveal that taxane resistance is more prevalent in patients with DIF-GC, support assessment of drug-target engagement as an early read-out of taxane clinical efficacy, and encourage the investigation of kinesins and other microtubule-associated proteins as potentially targetable mediators of taxane resistance in gastric cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Docetaxel/farmacología , Microtúbulos/efectos de los fármacos , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Biopsia , Línea Celular Tumoral , Cisplatino/farmacología , Cisplatino/uso terapéutico , Docetaxel/uso terapéutico , Resistencia a Antineoplásicos , Femenino , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Humanos , Estimación de Kaplan-Meier , Cinesinas/metabolismo , Masculino , Microtúbulos/metabolismo , Persona de Mediana Edad , Proyectos Piloto , Supervivencia sin Progresión , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Tubulina (Proteína)/metabolismoRESUMEN
Kv7 channels are enriched at the axonal plasma membrane where their voltage-dependent potassium currents suppress neuronal excitability. Mutations in Kv7.2 and Kv7.3 subunits cause epileptic encephalopathy (EE), yet the underlying pathogenetic mechanism is unclear. Here, we used novel statistical algorithms and structural modeling to identify EE mutation hotspots in key functional domains of Kv7.2 including voltage sensing S4, the pore loop and S6 in the pore domain, and intracellular calmodulin-binding helix B and helix B-C linker. Characterization of selected EE mutations from these hotspots revealed that L203P at S4 induces a large depolarizing shift in voltage dependence of Kv7.2 channels and L268F at the pore decreases their current densities. While L268F severely reduces expression of heteromeric channels in hippocampal neurons without affecting internalization, K552T and R553L mutations at distal helix B decrease calmodulin-binding and axonal enrichment. Importantly, L268F, K552T, and R553L mutations disrupt current potentiation by increasing phosphatidylinositol 4,5-bisphosphate (PIP2), and our molecular dynamics simulation suggests PIP2 interaction with these residues. Together, these findings demonstrate that each EE variant causes a unique combination of defects in Kv7 channel function and neuronal expression, and suggest a critical need for both prediction algorithms and experimental interrogations to understand pathophysiology of Kv7-associated EE.