Lipopolymer mediated siRNA delivery targeting aberrant oncogenes for effective therapy of myeloid leukemia in preclinical animal models.

The clinical development of tyrosine kinase inhibitors (TKI) has led to great strides in improving the survival of chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) patients. But even the new generation TKIs are rendered futile in the face of evolving landscape of acquired mutations leading to drug resistance, necessitating the pursuit of alternative therapeutic approaches. In contrast to exploiting proteins as targets like most conventional drugs and TKIs, RNA Interference (RNAi) exerts its therapeutic action towards disease-driving aberrant genes. To realize the potential of RNAi, the major challenge is to efficiently deliver the therapeutic mediator of RNAi, small interfering RNA (siRNA) molecules. In this study, we explored the feasibility of using aliphatic lipid (linoleic acid and lauric acid)-grafted polymers (lipopolymers) for the delivery of siRNAs against the FLT3 oncogene in AML and BCR-ABL oncogene in CML. The lipopolymer delivered siRNA potently suppressed the proliferation AML and CML cells via silencing of the targeted oncogenes. In both AML and CML subcutaneous xenografts generated in NCG mice, intravenously administered lipopolymer/siRNA complexes displayed significant inhibitory effect on tumor growth. Combining siFLT3 complexes with gilteritinib allowed for reduction of effective drug dosage, longer duration of remission, and enhanced survival after relapse, compared to gilteritinib monotherapy. Anti-leukemic activity of siBCR-ABL complexes was similar in wild-type and TKI-resistant cells, and therapeutic efficacy was confirmed in vivo through prolonged survival of the NCG hosts systemically implanted with TKI-resistant cells. These results demonstrate the preclinical efficacy of lipopolymer facilitated siRNA delivery, providing a novel therapeutic platform for myeloid leukemias.

Biodistribution of Therapeutic Small Interfering RNAs Delivered with Lipid-Substituted Polyethylenimine-Based Delivery Systems.

Small interfering RNAs (siRNAs) have emerged as a powerful tool to manipulate gene expression in vitro. However, their potential therapeutic application encounters significant challenges, such as degradation in vivo, limited cellular uptake, and restricted biodistribution, among others. This study evaluates the siRNA delivery efficiency of three different lipid-substituted polyethylenimine (PEI)-based carriers, named Leu-Fect A-C, to different organs in vivo, including xenograft tumors, when injected into the bloodstream of mice. The siRNA analysis was undertaken by stem-loop RT-PCR, followed by qPCR or digital droplet PCR. Formulating siRNAs with a Leu-Fect series of carriers generated nanoparticles that effectively delivered the siRNAs into K652 and MV4-11 cells, both models of leukemia. The Leu-Fect carriers were able to successfully deliver BCR-Abl and FLT3 siRNAs into leukemia xenograft tumors in mice. All three carriers demonstrated significantly enhanced siRNA delivery into organs other than the liver, including the xenograft tumors. Preferential biodistribution of siRNAs was observed in the lungs and spleen. Among the delivery systems, Leu-Fect A exhibited the highest biodistribution into organs. In conclusion, lipid-substituted PEI-based delivery systems offer improvements in addressing pharmacokinetic challenges associated with siRNA-based therapies, thus opening avenues for their potential translation into clinical practice.

The epidemiological status of osteoporotic hip fractures: A bicentric comparative and retrospective study.

BACKGROUND: Osteoporotic hip fractures have posed a significant burden to society, and more epidemiological data is required. OBJECTIVE: To compare the epidemiological differences of hip fracture patients in Spain and China. METHOD: This was a retrospective comparative study. Comparisons were made in terms of morbidity, demographic and anthropometric characteristics, length of stay, cost of hospitalization, and mortality by consulting the medical histories of osteoporotic hip fractures in two hospitals. The t test was used for measurement data, and the X2 test was used for count data. The difference is statistically significant when p< 0.05. RESULTS: A total of 757 patients were enrolled in this study, with 426 from Virgen Macarena University Hospital (HUVM) and 331 from Xi'an Daxing Hospital (XDH). The average age was 81.4 ± 9.26 and 76.0 ± 8.08 years; the proportion of women was 74.9% and 68.0%, respectively. The incidence of osteoporotic hip fractures in Seville residents over 50 years old was approximately 239 per 100,000 residents, compared to 158 per 100,000 residents in Xi'an. The timing of surgery in Spanish patients was significantly longer than in Chinese patients, 78.7 ± 48.2 vs. 60.7 ± 43.1 hours, p= 0.000. There were 81 deaths in Spain and 43 deaths in China during the one-year follow-up period (p= 0.026). CONCLUSIONS: In terms of incidence, demographics, surgical methods, and mortality, there are significant differences between hip fracture patients in Seville, Spain and Xi'an, China.

Exosomes: Potential Disease Biomarkers and New Therapeutic Targets.

Exosomes are extracellular vesicles released by cells, both constitutively and after cell activation, and are present in different types of biological fluid. Exosomes are involved in the pathogenesis of diseases, such as cancer, neurodegenerative diseases, pregnancy disorders and cardiovascular diseases, and have emerged as potential non-invasive biomarkers for the detection, prognosis and therapeutics of a myriad of diseases. In this review, we describe recent advances related to the regulatory mechanisms of exosome biogenesis, release and molecular composition, as well as their role in health and disease, and their potential use as disease biomarkers and therapeutic targets. In addition, the advantages and disadvantages of their main isolation methods, characterization and cargo analysis, as well as the experimental methods used for exosome-mediated drug delivery, are discussed. Finally, we present potential perspectives for the use of exosomes in future clinical practice.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: Executive summary.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: executive summary.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: Executive summary.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: Executive summary.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias.

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Investigating the Influence of Membrane Composition on Protein-Glycolipid Binding Using Nanodiscs and Proxy Ligand Electrospray Ionization Mass Spectrometry.

This work describes a versatile analytical approach, which combines the proxy ligand electrospray ionization mass spectrometry (ESI-MS) assay and model membranes of defined composition, to quantify the influence of lipid bilayer composition on protein-glycolipid binding in vitro. To illustrate the implementation of the assay (experimental design and data analysis), affinities of the monosialoganglioside ligand GM1, incorporated into nanodiscs (NDs), for cholera toxin B subunit homopentamer (CTB5) were measured. A series of NDs containing GM1 and cholesterol were prepared using three different phospholipids (1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)), and the average GM1 and cholesterol content of each ND were determined. The intrinsic affinities of GM1-containing NDs prepared with the three phospholipids are found to be similar in magnitude, indicating that small differences in the fatty acid chain length and the number of unsaturated bonds do not significantly affect the CTB5-GM1 interaction. Moreover, the measured affinities are similar to the value measured for GM1 pentasaccharide, indicating that neither the ceramide moiety nor the surface of the phospholipid membrane plays a significant role in CTB5 binding. The intrinsic (per binding site) affinity of the CTB5-GM1 interaction was found to decrease with increasing GM1 content of the ND, consistent with the occurrence of GM1 clustering in the membrane, which sterically hinders binding to CTB5. Notably, the addition of cholesterol to GM1-containing NDs did not have a significant effect on the strength of the CTB5-GM1 interaction. This result, which is at odds with the findings of a previous study of CTB5 binding to GM1 in vesicles, suggests that cholesterol does not "mask" GM1, at least not in NDs. These data, in addition to providing new insights into the influence of membrane composition on CTB5-GM1 binding, demonstrate the potential of the proxy ligand ESI-MS approach for comprehensive and quantitative studies of lectin interactions with glycolipids in native-like, membrane environments.

Cardiac Sympathetic Denervation for Refractory Ventricular Arrhythmias.

BACKGROUND: Cardiac sympathetic denervation (CSD) has been shown to reduce the burden of implantable cardioverter-defibrillator (ICD) shocks in small series of patients with structural heart disease (SHD) and recurrent ventricular tachyarrhythmias (VT). OBJECTIVES: This study assessed the value of CSD and the characteristics associated with outcomes in this population. METHODS: Patients with SHD who underwent CSD for refractory VT or VT storm at 5 international centers were analyzed by the International Cardiac Sympathetic Denervation Collaborative Group. Kaplan-Meier analysis was used to estimate freedom from ICD shock, heart transplantation, and death. Cox proportional hazards models were used to analyze variables associated with ICD shock recurrence and mortality after CSD. RESULTS: Between 2009 and 2016, 121 patients (age 55 ± 13 years, 26% female, mean ejection fraction of 30 ± 13%) underwent left or bilateral CSD. One-year freedom from sustained VT/ICD shock and ICD shock, transplant, and death were 58% and 50%, respectively. CSD reduced the burden of ICD shocks from a mean of 18 ± 30 (median 10) in the year before study entry to 2.0 ± 4.3 (median 0) at a median follow-up of 1.1 years (p < 0.01). On multivariable analysis, pre-procedure New York Heart Association functional class III and IV heart failure and longer VT cycle lengths were associated with recurrent ICD shocks, whereas advanced New York Heart Association functional class, longer VT cycle lengths, and a left-sided-only procedure predicted the combined endpoint of sustained VT/ICD shock recurrence, death, and transplantation. Of the 120 patients taking antiarrhythmic medications before CSD, 39 (32%) no longer required them at follow-up. CONCLUSIONS: CSD decreased sustained VT and ICD shock recurrence in patients with refractory VT. Characteristics independently associated with recurrence and mortality were advanced heart failure, VT cycle length, and a left-sided-only procedure.

Bilateral C1 laminar hooks combined with C2 pedicle screw fixation in the treatment of atlantoaxial subluxation after Grisel syndrome.

BACKGROUND CONTEXT: Many etiologies can lead to atlantoaxial subluxaion. In Grisel syndrome (GS), this subluxation occurs spontaneously after inflammatory processes of the head and neck. Diagnosis is typically based on clinical history and a strong suspicion of this syndrome. Nonsurgical treatment most often resolves the symptoms; however, in some cases surgical treatment is necessary to repair the subluxation. Various surgical techniques and instrumentation systems have been used to treat atlantoaxial subluxation, although there is no consensus regarding the best treatment method for the pediatric population. PURPOSE: To describe a case of atlantoaxial subluxation in a child with GS treated surgically with an alternative construct. STUDY DESIGN/SETTING: This is a case report and literature review. MATERIALS AND METHODS: Our case study involves a 5-year-old girl with a 6-month history of unresolved Fielding type II atlantoaxial subluxation caused by GS. Despite conservative treatment, the patient's symptoms continued to progress. After two failed closed reduction attempts, open reduction and C1-C2 fusion were performed with atlas laminar hook and axis pedicle polyaxial screws. A literature review of the surgical treatment of GS was also performed. RESULTS: After surgery, the patient exhibited full clinical and functional recovery with complete resolution of symptoms. At the 36-month follow-up examination, there was continual evidence of satisfactory reduction and fusion. No complications were observed. Upon completion of the literature review, eight GS cases were found to have been treated surgically with the minimum patient age being 9 years. CONCLUSIONS: Conservative management of GS is the most common and effective treatment; however, a few surgical cases have been reported in the literature with good results. Satisfactory clinical results and fusion at 36 months post surgery were seen in a pediatric patient with atlantoaxial subluxation and instability using atlas laminar hook and axis pedicle polyaxial screws.