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1.
Cell ; 170(2): 352-366.e13, 2017 Jul 13.
Article in English | MEDLINE | ID: mdl-28709002

ABSTRACT

Interactions between stromal fibroblasts and cancer cells generate signals for cancer progression, therapy resistance, and inflammatory responses. Although endogenous RNAs acting as damage-associated molecular patterns (DAMPs) for pattern recognition receptors (PRRs) may represent one such signal, these RNAs must remain unrecognized under non-pathological conditions. We show that triggering of stromal NOTCH-MYC by breast cancer cells results in a POL3-driven increase in RN7SL1, an endogenous RNA normally shielded by RNA binding proteins SRP9/14. This increase in RN7SL1 alters its stoichiometry with SRP9/14 and generates unshielded RN7SL1 in stromal exosomes. After exosome transfer to immune cells, unshielded RN7SL1 drives an inflammatory response. Upon transfer to breast cancer cells, unshielded RN7SL1 activates the PRR RIG-I to enhance tumor growth, metastasis, and therapy resistance. Corroborated by evidence from patient tumors and blood, these results demonstrate that regulation of RNA unshielding couples stromal activation with deployment of RNA DAMPs that promote aggressive features of cancer. VIDEO ABSTRACT.


Subject(s)
Breast Neoplasms/pathology , Exosomes/pathology , RNA, Untranslated/metabolism , Stromal Cells/pathology , Tumor Microenvironment , Breast Neoplasms/metabolism , DEAD Box Protein 58/metabolism , Exosomes/metabolism , Humans , Interferon Regulatory Factors/metabolism , MCF-7 Cells , Neoplasm Metastasis , RNA Polymerase III/genetics , RNA Polymerase III/metabolism , Receptors, Immunologic , Receptors, Pattern Recognition/metabolism , Signal Recognition Particle/metabolism , Stromal Cells/metabolism , Virus Diseases/metabolism
2.
Cell ; 167(6): 1540-1554.e12, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27912061

ABSTRACT

Therapeutic blocking of the PD1 pathway results in significant tumor responses, but resistance is common. We demonstrate that prolonged interferon signaling orchestrates PDL1-dependent and PDL1-independent resistance to immune checkpoint blockade (ICB) and to combinations such as radiation plus anti-CTLA4. Persistent type II interferon signaling allows tumors to acquire STAT1-related epigenomic changes and augments expression of interferon-stimulated genes and ligands for multiple T cell inhibitory receptors. Both type I and II interferons maintain this resistance program. Crippling the program genetically or pharmacologically interferes with multiple inhibitory pathways and expands distinct T cell populations with improved function despite expressing markers of severe exhaustion. Consequently, tumors resistant to multi-agent ICB are rendered responsive to ICB monotherapy. Finally, we observe that biomarkers for interferon-driven resistance associate with clinical progression after anti-PD1 therapy. Thus, the duration of tumor interferon signaling augments adaptive resistance and inhibition of the interferon response bypasses requirements for combinatorial ICB therapies.


Subject(s)
CTLA-4 Antigen/antagonists & inhibitors , Melanoma/immunology , Melanoma/therapy , Radioimmunotherapy , Animals , B7-H1 Antigen/metabolism , Cell Line, Tumor , Drug Resistance, Neoplasm , Heterografts , Humans , Interferons/immunology , Melanoma/drug therapy , Melanoma/radiotherapy , Mice , Neoplasm Transplantation , STAT1 Transcription Factor , T-Lymphocytes/immunology
3.
Cell ; 159(3): 499-513, 2014 Oct 23.
Article in English | MEDLINE | ID: mdl-25417103

ABSTRACT

Stromal communication with cancer cells can influence treatment response. We show that stromal and breast cancer (BrCa) cells utilize paracrine and juxtacrine signaling to drive chemotherapy and radiation resistance. Upon heterotypic interaction, exosomes are transferred from stromal to BrCa cells. RNA within exosomes, which are largely noncoding transcripts and transposable elements, stimulates the pattern recognition receptor RIG-I to activate STAT1-dependent antiviral signaling. In parallel, stromal cells also activate NOTCH3 on BrCa cells. The paracrine antiviral and juxtacrine NOTCH3 pathways converge as STAT1 facilitates transcriptional responses to NOTCH3 and expands therapy-resistant tumor-initiating cells. Primary human and/or mouse BrCa analysis support the role of antiviral/NOTCH3 pathways in NOTCH signaling and stroma-mediated resistance, which is abrogated by combination therapy with gamma secretase inhibitors. Thus, stromal cells orchestrate an intricate crosstalk with BrCa cells by utilizing exosomes to instigate antiviral signaling. This expands BrCa subpopulations adept at resisting therapy and reinitiating tumor growth.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/radiotherapy , Exosomes/metabolism , Paracrine Communication , Stromal Cells/metabolism , Animals , Breast Neoplasms/metabolism , Cell Line, Tumor , Computer Simulation , Drug Resistance, Neoplasm , Female , Humans , Interferons/metabolism , Mice, Nude , Radiation Tolerance , Receptors, Notch/metabolism , STAT1 Transcription Factor/metabolism , Signal Transduction , rab GTP-Binding Proteins/metabolism
4.
PLoS Biol ; 21(10): e3002332, 2023 10.
Article in English | MEDLINE | ID: mdl-37847673

ABSTRACT

Thermosensation is critical for the survival of animals. However, mechanisms through which nutritional status modulates thermosensation remain unclear. Herein, we showed that hungry Drosophila exhibit a strong hot avoidance behavior (HAB) compared to food-sated flies. We identified that hot stimulus increases the activity of α'ß' mushroom body neurons (MBns), with weak activity in the sated state and strong activity in the hungry state. Furthermore, we showed that α'ß' MBn receives the same level of hot input from the mALT projection neurons via cholinergic transmission in sated and hungry states. Differences in α'ß' MBn activity between food-sated and hungry flies following heat stimuli are regulated by distinct Drosophila insulin-like peptides (Dilps). Dilp2 is secreted by insulin-producing cells (IPCs) and regulates HAB during satiety, whereas Dilp6 is secreted by the fat body and regulates HAB during the hungry state. We observed that Dilp2 induces PI3K/AKT signaling, whereas Dilp6 induces Ras/ERK signaling in α'ß' MBn to regulate HAB in different feeding conditions. Finally, we showed that the 2 α'ß'-related MB output neurons (MBONs), MBON-α'3 and MBON-ß'1, are necessary for the output of integrated hot avoidance information from α'ß' MBn. Our results demonstrate the presence of dual insulin modulation pathways in α'ß' MBn, which are important for suitable behavioral responses in Drosophila during thermoregulation under different feeding states.


Subject(s)
Drosophila Proteins , Animals , Drosophila/metabolism , Drosophila melanogaster/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Insulin/metabolism , Mushroom Bodies/physiology , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction
5.
Nature ; 571(7763): 90-94, 2019 07.
Article in English | MEDLINE | ID: mdl-31270480

ABSTRACT

Silicon dominates contemporary solar cell technologies1. But when absorbing photons, silicon (like other semiconductors) wastes energy in excess of its bandgap2. Reducing these thermalization losses and enabling better sensitivity to light is possible by sensitizing the silicon solar cell using singlet exciton fission, in which two excited states with triplet spin character (triplet excitons) are generated from a photoexcited state of higher energy with singlet spin character (a singlet exciton)3-5. Singlet exciton fission in the molecular semiconductor tetracene is known to generate triplet excitons that are energetically matched to the silicon bandgap6-8. When the triplet excitons are transferred to silicon they create additional electron-hole pairs, promising to increase cell efficiencies from the single-junction limit of 29 per cent to as high as 35 per cent9. Here we reduce the thickness of the protective hafnium oxynitride layer at the surface of a silicon solar cell to just eight angstroms, using electric-field-effect passivation to enable the efficient energy transfer of the triplet excitons formed in the tetracene. The maximum combined yield of the fission in tetracene and the energy transfer to silicon is around 133 per cent, establishing the potential of singlet exciton fission to increase the efficiencies of silicon solar cells and reduce the cost of the energy that they generate.

6.
Acc Chem Res ; 55(17): 2454-2466, 2022 09 06.
Article in English | MEDLINE | ID: mdl-35948428

ABSTRACT

We must accelerate the pace at which we make technological advancements to address climate change and disease risks worldwide. This swifter pace of discovery requires faster research and development cycles enabled by better integration between hypothesis generation, design, experimentation, and data analysis. Typical research cycles take months to years. However, data-driven automated laboratories, or self-driving laboratories, can significantly accelerate molecular and materials discovery. Recently, substantial advancements have been made in the areas of machine learning and optimization algorithms that have allowed researchers to extract valuable knowledge from multidimensional data sets. Machine learning models can be trained on large data sets from the literature or databases, but their performance can often be hampered by a lack of negative results or metadata. In contrast, data generated by self-driving laboratories can be information-rich, containing precise details of the experimental conditions and metadata. Consequently, much larger amounts of high-quality data are gathered in self-driving laboratories. When placed in open repositories, this data can be used by the research community to reproduce experiments, for more in-depth analysis, or as the basis for further investigation. Accordingly, high-quality open data sets will increase the accessibility and reproducibility of science, which is sorely needed.In this Account, we describe our efforts to build a self-driving lab for the development of a new class of materials: organic semiconductor lasers (OSLs). Since they have only recently been demonstrated, little is known about the molecular and material design rules for thin-film, electrically-pumped OSL devices as compared to other technologies such as organic light-emitting diodes or organic photovoltaics. To realize high-performing OSL materials, we are developing a flexible system for automated synthesis via iterative Suzuki-Miyaura cross-coupling reactions. This automated synthesis platform is directly coupled to the analysis and purification capabilities. Subsequently, the molecules of interest can be transferred to an optical characterization setup. We are currently limited to optical measurements of the OSL molecules in solution. However, material properties are ultimately most important in the solid state (e.g., as a thin-film device). To that end and for a different scientific goal, we are developing a self-driving lab for inorganic thin-film materials focused on the oxygen evolution reaction.While the future of self-driving laboratories is very promising, numerous challenges still need to be overcome. These challenges can be split into cognition and motor function. Generally, the cognitive challenges are related to optimization with constraints or unexpected outcomes for which general algorithmic solutions have yet to be developed. A more practical challenge that could be resolved in the near future is that of software control and integration because few instrument manufacturers design their products with self-driving laboratories in mind. Challenges in motor function are largely related to handling heterogeneous systems, such as dispensing solids or performing extractions. As a result, it is critical to understand that adapting experimental procedures that were designed for human experimenters is not as simple as transferring those same actions to an automated system, and there may be more efficient ways to achieve the same goal in an automated fashion. Accordingly, for self-driving laboratories, we need to carefully rethink the translation of manual experimental protocols.


Subject(s)
Algorithms , Laboratories , Humans , Reproducibility of Results
7.
PLoS Genet ; 16(8): e1008963, 2020 08.
Article in English | MEDLINE | ID: mdl-32780743

ABSTRACT

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.


Subject(s)
Cyclic AMP Response Element-Binding Protein/genetics , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Memory, Long-Term/physiology , Neurons/metabolism , Smell/genetics , Trans-Activators/genetics , Animals , Animals, Genetically Modified , Calcium/metabolism , Drosophila melanogaster/physiology , Mushroom Bodies/physiology , Neurons/physiology , Protein Biosynthesis/genetics , Reward , Smell/physiology , Synaptic Transmission/genetics , Water
8.
PLoS Genet ; 15(5): e1008153, 2019 05.
Article in English | MEDLINE | ID: mdl-31071084

ABSTRACT

Electrical synapses between neurons, also known as gap junctions, are direct cell membrane channels between adjacent neurons. Gap junctions play a role in the synchronization of neuronal network activity; however, their involvement in cognition has not been well characterized. Three-hour olfactory associative memory in Drosophila has two components: consolidated anesthesia-resistant memory (ARM) and labile anesthesia-sensitive memory (ASM). Here, we show that knockdown of the gap junction gene innexin5 (inx5) in mushroom body (MB) neurons disrupted ARM, while leaving ASM intact. Whole-mount brain immunohistochemistry indicated that INX5 protein was preferentially expressed in the somas, calyxes, and lobes regions of the MB neurons. Adult-stage-specific knockdown of inx5 in αß neurons disrupted ARM, suggesting a specific requirement of INX5 in αß neurons for ARM formation. Hyperpolarization of αß neurons during memory retrieval by expressing an engineered halorhodopsin (eNpHR) also disrupted ARM. Administration of the gap junction blocker carbenoxolone (CBX) reduced the proportion of odor responsive αß neurons to the training odor 3 hours after training. Finally, the α-branch-specific 3-hour ARM-specific memory trace was also diminished with CBX treatment and in inx5 knockdown flies. Altogether, our results suggest INX5 gap junction channels in αß neurons for ARM retrieval and also provide a more detailed neuronal mechanism for consolidated memory in Drosophila.


Subject(s)
Connexins/genetics , Electrical Synapses/physiology , Mushroom Bodies/metabolism , Animals , Brain/metabolism , Carbenoxolone/pharmacology , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Electrical Synapses/metabolism , Gap Junctions/metabolism , Gap Junctions/physiology , Memory/physiology , Mushroom Bodies/physiology , Neurons/metabolism , Odorants , Smell/genetics , Synaptic Transmission/physiology
9.
Epilepsy Behav ; 113: 107464, 2020 12.
Article in English | MEDLINE | ID: mdl-33152580

ABSTRACT

RATIONALE: Lacosamide (LCM) was initially approved in Taiwan in March 2014 for use as adjunctive therapy for focal impaired awareness seizures and secondarily generalized seizures (SGS) in patients with epilepsy ≥16 years of age. The efficacy and tolerability of adjunctive LCM for the treatment of patients with focal seizures have been demonstrated in randomized, placebo-controlled trials. However, the trials do not reflect a flexible dose setting. This study (EP0063) was conducted to assess the safety and tolerability of LCM in real-world clinical practice in Taiwan. Effectiveness of LCM was also assessed as an exploratory objective. METHODS: EP0063 was a multicenter, prospective, noninterventional study with an expected observation period of 12 months ±â€¯60 days. Eligible patients were ≥16 years of age, had focal impaired awareness seizures and/or SGS (in line with approved indication in Taiwan at the time of the study), were taking at least one concomitant antiseizure medication (ASM), and had at least one seizure in the 3 months before baseline. Patients were prescribed LCM by their treating physician in the course of routine clinical practice. The primary safety variable was treatment-emergent adverse events (TEAEs) spontaneously reported to, or observed by, the treating physician. Based on safety data from previous studies of LCM and known side effects of other ASMs, certain TEAEs (including but not limited to cardiac and electrocardiogram, suicidality, and rash related terms) were analyzed separately. Effectiveness variables included Clinical Global Impression of Change (CGIC) and change in 28-day seizure frequency from baseline to 12 months (or final visit), and freedom from focal seizures. RESULTS: A total of 171 patients were treated with LCM, of whom 139 (81.3%) completed the study. The Kaplan-Meier estimated 12-month retention was 82.9%. Patients had a mean (standard deviation [SD], range) age of 38.5 (14.0, 16-77) years, and 96 (56.1%) were male. Patients were taking a mean (SD, range) of 2.8 (1.1, 1-6) ASMs at baseline. Mean (SD, range) duration of LCM treatment was 288.7 (111.9, 2-414) days, and the mean (SD, range) daily dosage of LCM was 205.0 (82.7, 50.0-505.2) mg/day. Overall, 95 (55.6%) patients reported at least one TEAE, most commonly dizziness (33 [19.3%] patients). Drug-related TEAEs were reported in 74 (43.3%) patients, and drug-related TEAEs leading to discontinuation of LCM were reported in 14 (8.2%) patients. Two (1.2%) patients died during LCM treatment, which were considered not related to LCM. Two (1.2%) patients had suicidality-related TEAEs; these TEAEs were considered either not related to LCM or the relationship was not recorded. Rash-related TEAEs were reported in five (2.9%) patients (considered LCM-related in two patients). Based on the CGIC, at 12 months (or final visit), 109 (63.7%) patients were considered to have improved, 54 (31.6%) had no change, and the remaining eight (4.7%) were minimally worse. At 12 months (or final visit), the median percentage change in focal seizure frequency was -50.0. During the first 6 months of the study, 21 (12.3%) patients were free from focal seizures; 37 (21.6%) patients were free from focal seizures in the last 6 months of the study; and 14 (8.2%) were free from focal seizures for the full 12 months of the study. CONCLUSIONS: Results of this prospective, noninterventional study suggest that adjunctive LCM was generally safe and well tolerated in this patient group in real-world practice in Taiwan. Effectiveness was also favorable, with more than 60% of patients considered to be improved by their physician at 12 months (or final visit).


Subject(s)
Anticonvulsants , Epilepsy , Acetamides/adverse effects , Adult , Aged , Anticonvulsants/therapeutic use , Drug Therapy, Combination , Epilepsy/drug therapy , Humans , Infant , Lacosamide/therapeutic use , Male , Middle Aged , Prospective Studies , Taiwan , Treatment Outcome
10.
Acta Neurochir (Wien) ; 162(2): 261-269, 2020 02.
Article in English | MEDLINE | ID: mdl-31781997

ABSTRACT

BACKGROUND: Electrical cortical stimulation is shown effective in treating patients with drug-resistant epilepsy. We demonstrated how detailed procedures of pre- and intra-operative planning of cortical stimulation implantation may influence the results of seizure reduction rate. METHODS: To confirm the precision of subdural grids covering the epileptogenic foci in the eloquent regions, pre- and intra-operative video-electroencephalography (VEEG) were performed in patients with drug-resistant epilepsy during a 4-day 24-h monitoring. The localization of the grid was determined via 3D reconstruction imaging of subdural electrodes co-registered onto the patient's cortex. A final quadripolar lead in cyclic stimulation mode was then placed and secured on the target cortex area. Post-operative 3D CT ensured the accurate location of stimulation lead without any misplacement. Bipolar cyclic stimulation and post-implantation VEEG were performed for 7 days. Patients were discharged and followed up regularly for parameters adjustment and recording of seizure outcomes. RESULTS: Eight patients received chronic cortical stimulation implantations between February 2003 and December 2017. The mean age of these patients was 21.1 years old and the average post-operative follow-up was 77.3 months. Comparisons of their seizure frequency at baseline and during the postoperative period revealed a mean reduction in seizures of 60.4% at the first year and 65.6% at the second year. CONCLUSIONS: Pre-surgical planning enhanced the accuracy of electrode placement and led to a favorable seizure reduction rate. Our report confirms that electrical cortical stimulation with detailed implantation procedures is safe and effective for patients with drug-resistant epilepsy originating from eloquent cortex.


Subject(s)
Deep Brain Stimulation/methods , Drug Resistant Epilepsy/therapy , Adolescent , Adult , Deep Brain Stimulation/instrumentation , Electrodes, Implanted , Electroencephalography/methods , Female , Humans , Male , Sensorimotor Cortex/physiopathology , Treatment Outcome
11.
BMC Cancer ; 19(1): 1265, 2019 Dec 30.
Article in English | MEDLINE | ID: mdl-31888521

ABSTRACT

BACKGROUND: Ganglioneuromas (GNs) are composed of mature ganglion cells and Schwann cells with a fibrous stroma; GNs are most often observed in children and young adults. The majority of non-cranial GNs are located in the retroperitoneum and posterior mediastinum. Other reported rare sites include the adrenal gland, small intestine, colon and urinary bladder. However, para-testicular GNs are even more rare. CASE PRESENTATION: Herein, we report the case of a patient with concurrent adrenal GN and thyroid papillary carcinoma who developed paratesticular GN eighteen years later. CONCLUSIONS: We conclude that there is an association among papillary thyroid carcinoma, GN and MEN2 syndromes. This case report may provide important information for the proposed association. However, further studies are required.


Subject(s)
Adrenal Gland Neoplasms/diagnosis , Adrenal Glands/pathology , Ganglioneuroma/diagnosis , Multiple Endocrine Neoplasia/diagnosis , Neoplasms, Second Primary/diagnosis , Schwann Cells/pathology , Testicular Neoplasms/diagnosis , Thyroid Cancer, Papillary/diagnosis , Thyroid Neoplasms/diagnosis , Adrenal Glands/diagnostic imaging , Adrenalectomy , Humans , Magnetic Resonance Imaging , Male , Medical History Taking , Middle Aged
12.
Epilepsia ; 60 Suppl 1: 47-59, 2019 03.
Article in English | MEDLINE | ID: mdl-30869168

ABSTRACT

Perampanel is an approved adjunctive treatment for focal seizures with or without focal to bilateral tonic-clonic (FBTC) seizures and generalized tonic-clonic (GTC) seizures. We compared efficacy and safety of perampanel vs placebo in Asian and non-Asian populations in a post hoc analysis of pooled data from 5 randomized phase 3 studies. Patients (≥12 years old) with focal + FBTC seizures received perampanel 2, 4, 8, or 12 mg or placebo; patients with GTC seizures received perampanel 8 mg or placebo (titration: 4-6 weeks; maintenance: 13 weeks). Efficacy endpoints included median percentage change in FBTC or GTC seizure frequency per 28 days and 50% responder rate relative to baseline. Median percentage change in FBTC seizure frequency was significantly greater for perampanel 8 and 12 mg than placebo in the Asian population (median difference from placebo: -30.32%, P = 0.0017; -30.06%, P = 0.0008, respectively) and perampanel 4, 8, and 12 mg in the non-Asian population (-35.07%, P = 0.0001; -37.78%, P < 0.0001; -34.53%, P < 0.0001, respectively). In both populations, median percentage change in GTC seizure frequency was significantly greater for perampanel 8 mg than placebo (median difference from placebo: Asian, -37.37%, P = 0.0139; non-Asian, -27.04%, P = 0.0006). The 50% responder rates were significantly greater than placebo for perampanel 8 and 12 mg for FBTC seizures (Asian: 58.0%, P = 0.0017 and 58.6%, P = 0.0013, respectively; non-Asian: 59.3%, P < 0.0001 and 54.3%, P = 0.0050, respectively) and perampanel 8 mg for GTC seizures (Asian: 57.6%, P = 0.0209; non-Asian: 68.8%, P = 0.0329). Pooled FBTC/GTC seizure data showed generally similar patterns of response to perampanel in both populations. The most frequent treatment-related adverse events were fatigue, irritability, dizziness, somnolence, and headache. Perampanel was effective, well tolerated, and can be considered a therapeutic option for FBTC/GTC seizures in Asian populations.


Subject(s)
Anticonvulsants/therapeutic use , Epilepsy, Generalized/drug therapy , Epilepsy, Partial, Motor/drug therapy , Epilepsy, Tonic-Clonic/drug therapy , Pyridones/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Anticonvulsants/adverse effects , Asian People , Child , Dose-Response Relationship, Drug , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Nitriles , Pyridones/adverse effects , Seizures/drug therapy , Treatment Outcome , Young Adult
13.
Nanomedicine ; 20: 101992, 2019 08.
Article in English | MEDLINE | ID: mdl-30981818

ABSTRACT

In previously published studies, intra-arterial (i.a.), but not intravenous (i.v.) delivery of recombinant tissue-type plasminogen activator (rtPA) immobilized on the surface of magnetic nanoparticles induces thrombolysis by magnetic targeting. We asked whether i.v. delivery of protected rtPA in a thermosensitive magnetoliposome (TML@rtPA) may achieve target thrombolysis. PEGylated TML@rtPA was optimized and characterized; controlled release of rtPA was achieved by thermodynamic and magnetic manipulation in vitro. The lysis index of TML@rtPA incubated with blood at 43 °C vs. 37 °C was 53 ±â€¯11% vs. 81 ±â€¯3% in thromboelastograms, suggesting thermosensitive thrombolysis of TML@rtPA. In a rat embolic model with superfusion of 43 °C saline on a focal spot on the iliac artery with clot lodging, release of rtPA equivalent to 20% regular dose from TML@rtPA administered i.a. vs. i.v. significantly restored iliac blood flow 15 vs. 55 min after clot lodging, respectively. TML@rtPA with magnetic guiding and focal hyperthermia may be potentially amendable to target thrombolysis.


Subject(s)
Hyperthermia, Induced , Magnetic Phenomena , Thrombolytic Therapy , Tissue Plasminogen Activator/administration & dosage , Administration, Intravenous , Animals , Biocompatible Materials/chemistry , Liposomes , Male , Nanocomposites/chemistry , Nanocomposites/ultrastructure , Particle Size , Rats, Sprague-Dawley , Temperature , Thrombosis
14.
J Ultrasound Med ; 38(5): 1333-1340, 2019 May.
Article in English | MEDLINE | ID: mdl-30393875

ABSTRACT

OBJECTIVES: In physiologic pulsatile flow, velocity acceleration is an independent factor determining wall shear stress experienced by the vascular endothelium. The purpose of this study was to evaluate Doppler indices of systolic velocity acceleration in extracranial cerebral vessels and the occurrence of intracranial aneurysms. METHODS: We reviewed medical records and 3.0-T brain magnetic resonance imaging with 3-dimensional time-of-flight magnetic resonance angiography of 1323 adults who underwent health checkups from June 2006 to November 2011, in whom 53 intracranial aneurysms were identified in 45 patients. Doppler ultrasound parameters of the carotid and vertebral arteries were analyzed in these 45 patients with aneurysms and compared with another 45 control participants matched for age and sex. We defined the maximum systolic acceleration (ACCmax ) as the maximum slope of the early phase of systolic acceleration on the Doppler waveform and the maximum acceleration index (AImax ) as the ratio of the ACCmax and peak systolic velocity. RESULTS: The Doppler analysis showed a significantly increased AImax and ACCmax in the common carotid artery (CCA), internal carotid artery, and vertebral artery in the aneurysm group. A cutoff 13.89 s-1 for the AImax of the CCA had sensitivity of 80% with a negative predictive value of 99% for intracranial aneurysms. CONCLUSIONS: This study suggests that the AImax of the CCA with a cutoff of 13.89 s-1 may be an alternative to 3-dimensional time-of-flight magnetic resonance angiography or computed tomographic angiography as a screening tool for intracranial aneurysms. Further prospective studies are needed to validate the diagnostic performance and cost-effectiveness of these indices for screening.


Subject(s)
Carotid Arteries/diagnostic imaging , Carotid Arteries/physiopathology , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/physiopathology , Ultrasonography, Doppler, Transcranial/methods , Blood Flow Velocity/physiology , Female , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Vertebral Artery/diagnostic imaging , Vertebral Artery/physiopathology
15.
Neurocrit Care ; 31(2): 329-337, 2019 10.
Article in English | MEDLINE | ID: mdl-30756319

ABSTRACT

BACKGROUND: The incidence of cefepime-induced neurotoxicity (CIN) has been previously underestimated, and there have only been sporadic reports from critical neurological settings. The present study aimed to investigate the potential factors associated with disease development, electroencephalography (EEG) sub-classification, and outcome measures. METHODS: The 10-year medical records of patients who underwent EEG between 2007 and 2016 at a tertiary medical center in Taiwan, and developed encephalopathy after cefepime therapy were retrospectively reviewed. Age- and sex-matched controls were included for further analysis. Demographic data, the occurrence of clinical seizures, non-convulsive status epilepticus (NCSE), use of antiepileptic drugs (AEDs), receiving maintenance or urgent hemodialysis, EEG findings, and functional outcomes were analyzed. The Chi-square test and a logistic regression model were applied to survey significant prognostic factors relating to mortality. RESULTS: A total of 42 CIN patients were identified, including 25 patients from wards and 17 from intensive care units; their mean age was 75.8 ± 11.8 years. Twenty-one patients (50%) had chronic kidney disease, and 18 (43%) had acute kidney injury. Among these patients, 32 (76%) received appropriate cefepime dose adjustment. Three patients had a normal renal function at the time of CIN onset. The logistic regression model suggested that maintenance hemodialysis and longer duration of cefepime use were independently associated with the development of CIN, with odds ratios of 3.8 and 1.2, respectively. NCSE was frequently noted in the CIN patients (64%). Generalized periodic discharge with or without triphasic morphology was the most common EEG pattern (38%), followed by generalized rhythmic delta activity and generalized spike-and-waves. AEDs were administered to 86% of the patients. A total of 17 patients (40%) did not survive to hospital discharge. Adequate cefepime dose adjustment and early cefepime discontinuation led to a better prognosis. CONCLUSIONS: CIN was associated with high mortality and morbidity rates. Neurotoxic symptoms could still occur when the cefepime dose was adjusted, or in patients with normal renal function. Patients with maintenance hemodialysis or a longer duration of cefepime therapy tended to develop CIN. Early recognition of abnormal EEG findings allowed for the withdrawal of the offending agent, resulting in clinical improvements and a better prognosis at discharge.


Subject(s)
Acute Kidney Injury/epidemiology , Anti-Bacterial Agents/adverse effects , Cefepime/adverse effects , Neurotoxicity Syndromes/epidemiology , Renal Insufficiency, Chronic/epidemiology , Status Epilepticus/epidemiology , Acute Kidney Injury/therapy , Aged , Aged, 80 and over , Anti-Bacterial Agents/administration & dosage , Cefepime/administration & dosage , Duration of Therapy , Electroencephalography , Female , Humans , Logistic Models , Male , Middle Aged , Neurotoxicity Syndromes/drug therapy , Neurotoxicity Syndromes/etiology , Neurotoxicity Syndromes/physiopathology , Odds Ratio , Prognosis , Renal Dialysis/statistics & numerical data , Renal Insufficiency, Chronic/therapy , Retrospective Studies , Risk Factors , Seizures/chemically induced , Seizures/drug therapy , Seizures/epidemiology , Seizures/physiopathology , Status Epilepticus/chemically induced , Status Epilepticus/drug therapy , Status Epilepticus/physiopathology , Taiwan/epidemiology
16.
Molecules ; 24(18)2019 Sep 19.
Article in English | MEDLINE | ID: mdl-31546842

ABSTRACT

In thrombolytic therapy, plasminogen activators (PAs) are still the only group of drug approved to induce thrombolysis, and therefore, critical for treatment of arterial thromboembolism, such as stroke, in the acute phase. Functionalized nanocomposites have attracted great attention in achieving target thrombolysis due to favorable characteristics associated with the size, surface properties and targeting effects. Many PA-conjugated nanocomposites have been prepared and characterized, and some of them has been demonstrated with therapeutic efficacy in animal models. To facilitate future translation, this paper reviews recent progress of this area, especially focus on how to achieve reproducible thrombolysis efficacy in vivo.


Subject(s)
Drug Delivery Systems , Plasminogen Activators/pharmacology , Thrombolytic Therapy , Animals , Disease Models, Animal , Humans , Nanocomposites/therapeutic use
17.
Epilepsy Behav ; 85: 188-194, 2018 08.
Article in English | MEDLINE | ID: mdl-30032806

ABSTRACT

AIM: This study investigated the efficacy and safety of perampanel (PER) adjunctive therapy in pediatric patients with epilepsy whose seizures are pharmacoresistant to existing antiepileptic drugs. METHODS: A clinical retrospective study was conducted from 2016 to 2017 in the pediatric neurology clinic at a tertiary children's hospital. We reviewed the data obtained from 66 children whose seizures were pharmacoresistant to more than two antiepileptic drugs, and could be followed up for a minimum of 3 months after PER adjunctive therapy initiation. The efficacy was estimated by the PER response rate at 3-, 6-, and 12-month follow-up evaluations, and adverse events were also recorded. RESULTS: The rate of seizure reduction of >50% was 30.3%, 37.5%, and 34.7% for all seizure types at 3, 6, and 12 months, in which 7.6%, 8.9%, and 14.3% of the patients became seizure-free at these time points, respectively. No significant differences were found between enzyme-inducing and nonenzyme-inducing antiepileptic drugs in combination with PER with regard to the responder rate. Five patients with Dravet syndrome were included in the study. Four of them (80%) exhibited 50% seizure reduction at the last visit, at which point, two patients (40.0%) were seizure-free. The retention rate was 51% at 12 months. Adverse events were documented in 25 patients (35.7%) and led to PER discontinuation in eight patients (12.1%). The most common adverse events comprised irritability, skin rash, dizziness, and somnolence; however, all were transient and successfully managed after PER dose reduction or discontinuation. CONCLUSION: The current data support the value of adjunctive PER in child and adolescent patients with pharmacoresistant epilepsy in daily clinical practice. Perampanel was efficacious and generally well-tolerated as an add-on treatment for epilepsy.


Subject(s)
Anticonvulsants/therapeutic use , Asian People , Drug Resistant Epilepsy/drug therapy , Drug Resistant Epilepsy/epidemiology , Outpatient Clinics, Hospital/trends , Pyridones/therapeutic use , Adolescent , Ambulatory Care Facilities/trends , Anticonvulsants/adverse effects , Child , Dizziness/chemically induced , Drug Resistant Epilepsy/diagnosis , Epilepsies, Myoclonic/diagnosis , Epilepsies, Myoclonic/drug therapy , Epilepsies, Myoclonic/epidemiology , Female , Follow-Up Studies , Humans , Male , Neurology/methods , Neurology/trends , Nitriles , Pediatrics/methods , Pediatrics/trends , Pyridones/adverse effects , Retrospective Studies , Rett Syndrome/diagnosis , Rett Syndrome/drug therapy , Rett Syndrome/epidemiology , Treatment Outcome
18.
Nat Mater ; 15(10): 1120-7, 2016 10.
Article in English | MEDLINE | ID: mdl-27500805

ABSTRACT

Virtual screening is becoming a ground-breaking tool for molecular discovery due to the exponential growth of available computer time and constant improvement of simulation and machine learning techniques. We report an integrated organic functional material design process that incorporates theoretical insight, quantum chemistry, cheminformatics, machine learning, industrial expertise, organic synthesis, molecular characterization, device fabrication and optoelectronic testing. After exploring a search space of 1.6 million molecules and screening over 400,000 of them using time-dependent density functional theory, we identified thousands of promising novel organic light-emitting diode molecules across the visible spectrum. Our team collaboratively selected the best candidates from this set. The experimentally determined external quantum efficiencies for these synthesized candidates were as large as 22%.

19.
J Formos Med Assoc ; 116(11): 825-836, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29046247

ABSTRACT

Radium-223 is a first-in-class α-emitting radiopharmaceutical that targets bone metastases associated with metastatic castration-resistant prostate cancer (mCRPC). In the pivotal phase III trial ALSYMPCA, radium-223 significantly increased overall survival (OS), compared with placebo (median 14.9 vs 11.3 months; hazard ratio 0.70; 95% CI 0.58-0.83; p < 0.001), in patients with mCRPC and symptomatic bone metastases-with a comparable safety profile. To optimize treatment outcomes, selection of appropriate patients is important. As well as osteoblastic bone metastases, mCRPC patients should be well enough to receive six doses of radium-223 as this treatment duration has been shown to greatly improve OS outcomes compared with administration of four or fewer doses. Additionally, alkaline phosphatase and lactate dehydrogenase are emerging as important biomarkers during radium-223 treatment. Optimal concomitant standard-of-care therapies (such as abiraterone or enzalutamide) to be administered with radium-223 have yet to be defined as does the most efficacious dose and duration of radium-223 treatment. In conclusion, radium-223 is an important addition to the mCRPC treatment landscape and marks a paradigm shift in the treatment of bone metastases.


Subject(s)
Bone Neoplasms/radiotherapy , Bone Neoplasms/secondary , Prostatic Neoplasms, Castration-Resistant/radiotherapy , Radiopharmaceuticals/therapeutic use , Radium/therapeutic use , Clinical Trials as Topic , Humans , Male , Prostatic Neoplasms, Castration-Resistant/pathology , Treatment Outcome
20.
J Am Chem Soc ; 138(27): 8639-52, 2016 07 13.
Article in English | MEDLINE | ID: mdl-27366818

ABSTRACT

Surface passivation has enabled the development of silicon-based solar cells and microelectronics. However, a number of emerging applications require a paradigm shift from passivation to functionalization, wherein surface functionality is installed proximal to the silicon surface. To address this need, we report here the use of persistent aminocarbenes to functionalize hydrogen-terminated silicon surfaces via Si-H insertion reactions. Through the use of model compounds (H-Si(TMS)3 and H-Si(OTMS)3), nanoparticles (H-SiNPs), and planar Si(111) wafers (H-Si(111)), we demonstrate that among different classes of persistent carbenes, the more electrophilic and nucleophilic ones, in particular, a cyclic (alkyl)(amino)carbene (CAAC) and an acyclic diaminocarbene (ADAC), are able to undergo insertion into Si-H bonds at the silicon surface, forming persistent C-Si linkages and simultaneously installing amine or aminal functionality in proximity to the surface. The CAAC (6) is particularly notable for its clean insertion reactivity under mild conditions that produces monolayers with 21 ± 3% coverage of Si(111) atop sites, commensurate with the expected maximum of ∼20%. Atomic force and transmission electron microscopy, nuclear magnetic resonance, X-ray photoelectron, and infrared spectroscopy, and time-of-flight secondary ion mass spectrometry provided evidence for the surface Si-H insertion process. Furthermore, computational studies shed light on the reaction energetics and indicated that CAAC 6 should be particularly effective at binding to silicon dihydride, trihydride, and coupled monohyride motifs, as well as oxidized surface sites. Our results pave the way for the further development of persistent carbenes as universal ligands for silicon and potentially other nonmetallic substrates.


Subject(s)
Hydrogen/chemistry , Methane/analogs & derivatives , Silicon/chemistry , Methane/chemistry , Models, Molecular , Molecular Conformation , Surface Properties
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