Predicting high-risk pre-capillary pulmonary hypertension: an echocardiographic multiparameter scoring index.

BACKGROUND: The risk stratification of pulmonary arterial hypertension proposed by the European Society of Cardiology /European Respiratory Society guidelines in 2015 and 2022 included two to three echocardiographic indicators. However, the specific value of echocardiography in risk stratification of pre-capillary pulmonary hypertension (pcPH) has not been efficiently demonstrated. Given the complex geometry of the right ventricular (RV) and influencing factors of echocardiographic parameter, there is no single echocardiographic parameter that reliably informs about PH status. We hypothesize that a multi-parameter comprehensive index can more accurately evaluate the severity of the pcPH. The purpose of this study was to develop and validate an echocardiographic risk score model to better assist clinical identifying high risk of pcPH during initial diagnosis and follow-up. METHODS: We studied 197 consecutive patients with pcPH. A multivariable echocardiographic model was constructed to predict the high risk of pcPH in the training set. Points were assigned to significant risk factors in the final model based on ß-coefficients. We validated the model internally and externally. RESULTS: The echocardiographic score was constructed by multivariable logistic regression, which showed that pericardial effusion, right atrial (RA) area, RV outflow tract proximal diameter (RVOT-Prox), the velocity time integral of the right ventricular outflow tract (TVIRVOT) and S' were predictors of high risk of pcPH. The area under curve (AUC) of the training set of the scoring model was 0.882 (95%CI: 0.809-0.956, p < 0.0001). External validation was tested in a test dataset of 77 patients. The AUC of the external validation set was 0.852. A 10-point score risk score was generated, with scores ranging from 0 to 10 in the training cohort. The estimate risk of high risk of pcPH ranged from 25.1 to 94.6%. CONCLUSIONS: The echocardiographic risk score using five echocardiographic parameters could be comprehensive and useful to predict the high risk of pcPH for initial assessment and follow-up.

A better method to evaluate the reliability of echocardiography for assessment of pulmonary hypertension: comparison of tricuspid regurgitant spectrum quality grading and tricuspid valve regurgitation degree.

Background: Transthoracic echocardiography (TTE) is recommended as the most important noninvasive screening tool for the diagnosis of pulmonary hypertension (PH), sonographers usually measure the volume of regurgitant flow rather than evaluating the spectral quality, so physicians will determine whether the ultrasound measurements of pulmonary arterial systolic pressure (US-PASP) are reliable based on the volume of tricuspid regurgitation (TR). Therefore, for the first time, we grade the quality of TR spectrum (TRS) based on its integrity and clarity, aiming to assess clinical application value of different tricuspid regurgitant spectrum quality grades (TR-SQG), and investigate whether the accuracy of US-PASP is more trustworthy than TR. Methods: We retrospectively analyzed 108 patients with chronic thromboembolic PH (CTEPH) to compare the correlation and agreement between US-PASP and right heart catheterization measurements of PASP (RHC-PASP). TR area (TRA) and TRS were measured in each patient, and TR-SQG was performed. Results: The correlation coefficients between US-PASP and RHC-PASP were r=0.622 (P<0.001), r=0.754 (P<0.001), r=0.595 (P<0.001) in mild, moderate, severe TR, and r=0.301 (P=0.135), r=0.747 (P<0.001), r=0.739 (P<0.001), r=0.828 (P<0.001) in TR-SQG I-IV, respectively. Bland-Altman analysis revealed the mean biases of 5.05, 3.06, 7.62 mmHg in mild, moderate, severe TR, and -16.47, -8.07, 1.82, 6.09 mmHg in TR-SQG I-IV, respectively. In mild TR with the TR-SQG III and IV, the correlation coefficients between US-PASP and RHC-PASP were r=0.779 (P<0.001), intraclass correlation coefficient (ICC) =0.774, paired t-test P=0.160, respectively; and the consistency was significantly higher than that of mild TR without considering TR-SQG. In moderate TR with the TR-SQG III and IV, the r=0.749, ICC =0.746, paired t-test P=0.298 between US-PASP and RHC-PASP. Conclusions: The US-PASP with TR-SQG III or IV is trustworthy, and its accuracy and consistency are better than those predicted by the traditional severity of TR. The establishment of the ultrasound evaluation system of TR-SQG helps clinicians to judge whether the US-PASP is accurate, credible, and reliable.

[18 F] -FAPI-42 PET/CT assessment of Progressive right ventricle fibrosis under pressure overload.

BACKGROUND: Right heart failure (RHF) is a complication of pulmonary hypertension (PH) and increases the mortality independently of the underlying disease. However, the process of RHF development and progression is not fully understood. We aimed to develop effective approaches for early diagnosis and precise evaluation of RHF. METHODS: Right ventricle (RV) pressure overload was performed via pulmonary artery banding (PAB) surgery in Sprague-Dawley (SD) rats to induce RHF. Echocardiography, right heart catheterization, histological staining, fibroblast activation protein (FAP) immunofluorescence and 18 F-labelled FAP inhibitor-42 ([18 F] -FAPI-42) positron emission tomography/computed tomography (PET/CT) were performed at day 3, week 1, 2, 4 and 8 after PAB. RNA sequencing was performed to explore molecular alterations between PAB and sham group at week 2 and week 4 after PAB respectively. RESULTS: RV hemodynamic disorders were aggravated, and RV function was declined based on right heart catheterization and echocardiography at week 2, 4 and 8 after PAB. Progressive cardiac hypertrophy, fibrosis and capillary rarefaction could be observed in RV from 2 to 8 weeks after PAB. RNA sequencing indicated 80 upregulated genes and 43 downregulated genes in the RV at both week 2 and week 4 after PAB; Gene Ontology (GO) analysis revealed that fibrosis as the most significant biological process in the RV under pressure overload. Immunofluorescence indicated that FAP was upregulated in the RV from week 2 to week 8 after PAB; and [18 F] -FAPI-42 PET/CT revealed FAPI uptake was significantly higher in RV at week 2 and further increased at week 4 and 8 after PAB. CONCLUSION: RV function is progressively declined with fibrosis as the most prominent molecular change after pressure overload, and [18 F] -FAPI-42 PET/CT is as sensitive and accurate as histopathology in RV fibrosis evaluation.

Automatic echocardiographic evaluation of the probability of pulmonary hypertension using machine learning.

Echocardiography, a simple and noninvasive tool, is the first choice for screening pulmonary hypertension (PH). However, accurate assessment of PH, incorporating both the pulmonary artery pressures and additional signs for PH remained unsatisfied. Thus, this study aimed to develop a machine learning (ML) model that can automatically evaluate the probability of PH. This cohort included data from 346 (275 for training set and internal validation set and 71 for external validation set) patients with suspected PH patients and receiving right heart catheterization. Echocardiographic images on parasternal short axis-papillary muscle level (PSAX-PML) view from all patients were collected, labeled, and preprocessed. Local features from each image were extracted and subsequently integrated to build a ML model. By adjusting the parameters of the model, the model with the best prediction effect is finally constructed. We used receiver-operating characteristic analysis to evaluate model performance and compared the ML model with the traditional methods. The accuracy of the ML model for diagnosis of PH was significantly higher than the traditional method (0.945 vs. 0.892, p = 0.027 [area under the curve [AUC]]). Similar findings were observed in subgroup analysis and validated in the external validation set (AUC = 0.950 [95% CI: 0.897-1.000]). In summary, ML methods could automatically extract features from traditional PSAX-PML view and automatically assess the probability of PH, which were found to outperform traditional echocardiographic assessments.

Clinical value of echocardiography in evaluating hemodynamics and right ventricular function in patients with chronic thromboembolic pulmonary hypertension after balloon pulmonary angioplasty.

Background: Patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) are eligible for balloon pulmonary angioplasty (BPA). However, the short-term effects of BPA on pulmonary hemodynamics and right ventricular (RV) function in patients with CTEPH have not been elucidated. In the current study, echocardiography was conducted to explore the short-term effects of BPA on inoperable CTEPH patients. Methods: A total of 30 inoperable CTEPH patients who underwent echocardiography before and after BPA were enrolled to the present retrospective study. Right heart catheterization (RHC) parameters, echocardiography function parameters, and echocardiography structural parameters of patients were evaluated at baseline and within 24 hours after BPA and the results were compared. Results: RHC parameters including pulmonary artery systolic pressure (PASP), pulmonary artery diastolic pressure (PADP), mean pulmonary artery pressure (mPAP), and pulmonary vascular resistance (PVR), and echocardiography structural parameters including right atrium diameter (RAD), right ventricular end-diastolic area (RVEDA), right ventricular end-systolic area (RVESA), right atrium end-diastolic area (RAEDA) and right atrium end-systolic area (RAESA) significantly improved within 24 h after BPA compared with the baseline results (P<0.05). However, there were no significant differences in echocardiography function parameters including tissue Doppler-derived tricuspid lateral annular systolic velocity (S'), tricuspid annular plane systolic excursion (TAPSE), right ventricular index of myocardial performance (RIMP), right ventricular fractional area change (RVFAC) and left ventricular stroke volume (LVSV) before and after BPA. Conclusions: The findings show that a single BPA procedure significantly improves RV volume load and reduces the pulmonary blood pressure in CTEPH patients in the short-term. However, BPA does not improve RV systolic function 24 hours after the procedure. The results indicate that evaluation of RV structural and function with echocardiography is an effective approach for non-invasive monitoring of patient status after BPA.

Direct Detection of Pulmonary Fibrosis by Near-Infrared-Responsive Biomimetic Platelets.

BACKGROUND: Pulmonary fibrosis (PF) is a fatal lung disease and affects over 5 million patients worldwide. Precise and early detection of PF is of pivotal importance to slow the disease progression. However, there are currently no effective tools to detect PF directly. PURPOSE: This study aimed to develop an imaging modality to detect PF directly. Excessive collagen deposition is the hallmark of PF. Herein, we developed a novel PF diagnostic agent, namely PVD (platelets-derived nanovesicles labeled with dye), by utilizing near-infrared (NIR)-responsive biomimetic platelets that specifically recognize collagen. METHODS: In brief, platelets membrane was extracted from purified platelets by freeze/thaw and formed to PVD nanovesicles via sonication and extrusion, when loaded with DiR dye. Red blood cells membrane loaded with DiR was prepared in the same way as PVD to form RVD as control. Collagen self-assembled on microplates was used as an in vitro collagen fibrils model and monocrotaline-induced rats were used as an in vivo PF model. RESULTS: We demonstrated that PVD, but not RVD nor other controls, could bind collagen both in vitro and in vivo, and directly detect pulmonary fibrosis in vivo and ex vivo at the early PF stage. CONCLUSION: Collectively, PVD is a versatile NIR-responsive probe for the direct visualization of collagen, and can be particularly helpful in direct detecting PF. To the best of our knowledge, PVD is the first report of a NIR probe for the direct detection of pulmonary fibrosis.

A Novel Biomimetic Nanoprobe as a Photoacoustic Contrast Agent.

Specific detection of tumors is of pivotal importance to cancer prevention and therapy yet a big challenge. Photoacoustic imaging (PAI) as an emerging non-invasive modality has shown great potential in biomedical and clinical applications. The performance of PAI largely depends on the light-absorption coefficient of the imaged tissue and the PAI contrast agent being used, either endogenously or exogenously. The exogenous contrast agents developed so far have greatly helped to improve PAI, but still have some limitations, such as lack of targeting capacity and easy clearance by the host immune system. Herein, we fabricated a biomimetic nanoprobe with cell membrane coating as a novel PAI contrast agent, namely, MPD [membrane-coated poly(lactic-co-glycolic acid) (PLGA)/dye]. In brief, the organic dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindotricarbocyanine iodide (DiR) was encapsulated by the Food and Drug Administration-approved polymer, poly(lactic-co-glycolic acid) (PLGA), to form polymer nanoparticles by emulsification. The nanoparticles are further coated with the cancer cell membrane to form MPD. MPD has outstanding biocompatibility, tumor specificity, and in vivo stability. Thus, MPD is a versatile NIR-I theranostic nanoplatform for PAI-guided cancer diagnosis and therapy.

A Combination of UTMD-Mediated HIF-1α shRNA Transfection and TAE in the Treatment of Hepatic Cancer.

To explore the antitumor effect of hypoxia-inducible factor-1α short hairpin RNA (HIF-1α shRNA) delivered by ultrasound targeted microbubble destruction (UTMD) and transcatheter arterial embolization (TAE) on rats with hepatic cancer. After the models of transplantation hepatoma were established, Wistar rats were randomly divided into 4 groups: Control group, UTMD group, TAE group, and UTMD+TAE group. Contrast-enhanced ultrasound (CEUS) was used to monitor tumor size on day 14 after four different treatments. Western blotting and immunohistochemistry were applied to measure the protein level of HIF-1α and VEGF in the hepatic cancer tissue. In comparison with UTMD+TAE group (21.25±10.68 days), the mean survival time was noticeably shorter in the Control group and TAE group (13.02±4.30 days and 15.03±7.32 days) (p<0.05, respectively). There was no statistical difference between UTMD+TAE group and UTMD group of the mean survival time (p>0.05). In addition, our results proved that the tumor sizes in UTMD+TAE group were obviously smaller than those in other groups (p<0.05, respectively). By CEUS, we clearly found that the tumor size was the smallest on day 14 in the UTMD+TAE group. The western blotting and immunohistochemistry results proved that the protein levels of HIF-1α and VEGF in UTMD+TAE group were obviously lower than those in TAE group and Control group on days 7 and 14 (p<0.05, respectively). However, there was no statistical difference between UTMD+TAE group and UTMD group (p>0.05). In this study we tried to explore the antitumor effect through a combination of UTMD-mediated HIF-1α shRNA transfection and TAE on rats with hepatic cancer. Our results showed that UTMD-mediated HIF-1α shRNA transfection and TAE can obviously silence HIF-1α and VEGF expression, thereby successfully inhibiting the growth of the tumor.

MiR-320a-3p/ELF3 axis regulates cell metastasis and invasion in non-small cell lung cancer via PI3K/Akt pathway.

MicroRNAs (miRNAs) play important roles in tumorigenesis and tumor progression. In this study, we investigated the role of miR-320a-3p in non-small cell lung cancer (NSCLC). Expressions of miR-320a-3p were firstly determined in 80 NSCLC patients' cancer tissues and adjacent normal lung tissues by qRT-PCR. Then MTT assay, cell migration and invasion assays were performed in vitro. Potential binding sites on target gene of miR-320a-3p were predicted and luciferase reporter assay was used to identify the potential binding sites. Tumorigenesis assay were performed in nude mice by injecting A549 cells which stably express miR-320a-3p. Results indicated that high expression of miR-320a-3p suppresses cell proliferation, migration and invasion through the inactivation of PI3K/Akt signaling pathway in NSCLC cells. Smaller tumor size and lighter weight were also found in nude mice which had miR-320a-3p higher expressed. Furthermore, data from luciferase reporter assay proved the direct binding of miR-320a-3p on the 3'UTR region of ELF3 mRNA, this could further decrease ELF3 expression transcriptionally. We provided evidence that miR-320a-3p might work as a tumor suppressor in NSCLC both in vivo and in vitro.

Elderly population have a decreased aneurysmal subarachnoid hemorrhage incidence rate than Middle aged population: a descriptive analysis of 8,144 cases in mainland China.

PURPOSE: Rupture of an intracranial aneurysm is a life-threatening acute cerebrovascular event. The purpose of this study was to investigate whether aneurysmal subarachnoid haemorrhage (SAH) incidence rate is higher or lower in elderly population than in middle aged population. MATERIALS AND METHODS: Aneurysmal SAH cases were collected retrospectively from the archives of 21 hospitals in Mainland China. All the cases were collected from September 2016 and backward consecutively for a period of time up to 8 years. SAH was initially diagnosed by brain computed tomography (CT). CT angiography (CTA) or digital subtraction angiography (DSA) was followed and SAH was confirmed to be due to cerebral aneurysm rupture. For cases when multiple bleeding occurred, the age of the first SAH was used in this study. The total incidence from all hospitals at each age group were summed together for females and males respectively; then adjusted by the total population number at each age group for females and males which was from the 2010 population census of the People's Republic of China. RESULTS: In total there were 8,144 cases of intracranial aneurysmal SAH, with 4,861 females and 3,283 males. For females the relative aneurysmal SAH incidence rate started to decrease after around 65 years old, while for males the relative aneurysmal SAH incidence rate started to decrease after around 53 years old. CONCLUSION: Our data tentatively suggest elderly patients may be at a reduced risk of rupture compared with patients who are younger while have similar other risk factors.

The putative tumor suppressor, miR-199a, regulated by Snail, modulates clear cell renal cell carcinoma aggressiveness by repressing ROCK1.

BACKGROUND: Aberrant expression of miR-199a has been frequently reported in cancer studies; however, its role in renal cell carcinoma (RCC) has not been examined in detail. RESULTS: Here, we showed that miR-199a was downregulated in RCC and associated with poor prognostic phenotype. Using luciferase and western blot assays we identified that Rho-associated coiled coil-containing protein kinases 1 (ROCK1) was a direct target gene for miR-199a. miR-199a regulated proliferation, invasion, and apoptosis of clear cell renal cell carcinoma (ccRCC) cells by modulating ROCK1 expression. Interestingly, we also found that miR-199a was modulated by snail in ccRCC cells. Snail elevated ROCK1 expression by repressing miR-199a activity. CONCLUSION: Altogether, our results identify a crucial tumor suppressive role of miR-199a in the progression of ccRCC and suggest that miR-199a might be an anticancer therapeutic target for ccRCC patients.

Overexpression of ELF3 facilitates cell growth and metastasis through PI3K/Akt and ERK signaling pathways in non-small cell lung cancer.

ELF3 is one of the member of transcription factors from E-twenty-six family, its role varies in different types of cancer. However, the role and specific mechanisms of ELF3 in the development of non-small cell lung cancer (NSCLC) still remains largely unknown. In our study, ELF3 was observed to be upregulated in NSCLC tissues compared to the corresponding normal lung tissue at mRNA and protein levels, and its expression level was correlated with the overall survival of patients with NSCLC. Silencing of the ELF3 gene in NSCLC cells inhibited the proliferation and metastasis significantly in vitro and in vivo. Conversely, overexpression of ELF3 in NSCLC cells promoted cancer growth and metastasis in vitro. Mechanistically, ELF3 activated PI3K/AKT and ERK signaling pathways and its downstream effectors, thus regulating the cell cycle and epithelial-mesenchymal transition (EMT). Furthermore, the promotive effects of ELF3 on cellular proliferation and metastasis could be rescued by Ly294002 (inhibitor of PI3K) and U0126 (inhibitor of MEK1/2). The results show that ELF3 promotes cell growth and metastasis by regulating PI3K/Akt and ERK pathways in NSCLC and that it may be a promising new target for the treatment of NSCLC patients.

The putative tumour suppressor microRNA-145, repressed by c-jun, modulates clear cell renal cell carcinoma aggressiveness by repressing ROCK1.

Aberrant expression of miR-145 has frequently been reported in cancer studies; however, its role in renal cell carcinoma (RCC) has not been examined in detail. Here, we showed that miR-145 was downregulated in RCC cells and tissues and associated with a poor prognostic phenotype in RCC patients. Restoration of miR-145 suppressed proliferation and invasion and induced apoptosis in clear cell RCC (ccRCC) cells. By luciferase and western blot assays we identified ROCK1 as a direct target gene for miR-145. Furthermore, a reverse correlation between miR-145 and ROCK1 expression was observed in ccRCC tissues. In addition, we revealed that miR-145 down-regulation in ccRCC cells was due to EZH2-mediated histone methylation. Altogether, these results identify a crucial tumor suppressive role of miR-145 in the progression of ccRCC and suggest that miR-145 might be an anticancer therapeutic target for ccRCC patients.

Elevated Expression of Zinc Finger Protein 703 Promotes Cell Proliferation and Metastasis through PI3K/AKT/GSK-3ß Signalling in Oral Squamous Cell Carcinoma.

BACKGROUND/AIMS: Zinc finger protein 703 (ZNF703), initially identified as a novel oncogene in human breast cancer, is a member of the NET/NlZ family of zinc finger transcription factors. It is recognized that the overexpression of ZNF703 is associated with various types of human cancers, but the role and molecular mechanism of ZNF703 in oral squamous cell carcinoma (OSCC) are unknown. METHODS: ZNF703 expression levels were examined in OSCC tissues and non-cancerous tissues by qRT-PCR and immunohistochemistry (IHC). The molecular mechanisms of ZNF703 and its effects on cell growth and metastasis were explored in vitro and in vivo using the CCK8 assay, colony formation assay, cell cycle analysis, migration and invasion assays, wound-healing assay, western blotting and xenograft experiments in nude mice. RESULTS: In this study, ZNF703 was found to be upregulated in OSCC tissues compared to that in normal tissues at both mRNA and protein levels, and its expression level was closely correlated with the overall survival of patients with OSCC. Silencing of the ZNF703 gene in OSCC cells significantly inhibited cell growth and metastasis in vitro and in vivo. Conversely, the overexpression of ZNF703 in OSCC cells promoted cancer growth and metastasis in vitro. Mechanistically, ZNF703 activated the PI3K/AKT/GSK-3ß signalling pathway and its downstream effectors, thus regulating the cell cycle and epithelial-mesenchymal transition (EMT). Furthermore, the promotive effects of ZNF703 on cellular proliferation and metastasis could be rescued by LY294002 (a PI3K-specific inhibitor) and MK2206 (an Akt-specific inhibitor). CONCLUSION: The results show that ZNF703 promotes cell growth and metastasis through PI3K/Akt/GSK-3ß signalling in OSCC and that it may be a promising target in the treatment of patients with OSCC.

Efficient gene delivery to myocardium with ultrasound targeted microbubble destruction and polyethylenimine.

The aim of present study was to evaluate the feasibility and efficiency of enhanced green fluorescent protein (EGFP) gene delivery to myocardium in vivo by ultrasound targeted microbubble destruction (UTMD) and polyethylenimine (PEI). SonoVue/DNA and PEI/DNA/SonoVue complexes were prepared. Gel electrophoresis analysis was performed to determine the structural integrity of plasmid DNA or PEI/DNA after UTMD. Solutions of plasmid DNA, SonoVue/DNA, PEI/DNA complexes or PEI/DNA/SonoVue complexes were respectively transduced into BALB/c mice hearts by means of transthoracic ultrasound irradiation. Mice undergoing PBS injection, plasmid injection or PEI/DNA complexes injection without ultrasound irradiation served as controls. Gene expression in myocardium was detected 4 days after treatment. Cryosections and histological examinations were conducted. Electrophoresis gel assay showed no damage to DNA or PEI/DNA complexes after UTMD. When the heart was not exposed to ultrasound, the expression of EGFP was observed in the subendocardial myocardium obviously. The strongest expression was detected in the anterior wall of the left ventricle when the heart was exposed to ultrasound alone. Injection of PEI/DNA complexes and UTMD resulted in the highest transfection efficiency and the distributional difference of EGFP was not obvious. No tissue damage was seen histologically. In conclusion, a combination of UTMD and PEI was highly effective in transfecting mice hearts without causing any apparently adverse effect. It provides an alternative to current clinical gene therapy and opens a new concept of non-viral gene delivery for the treatment of cardiac disease.

Efficient Gene Delivery to Myocardium with Ultrasound Targeted Microbubble Destruction and Polyethylenimine / 华中科技大学学报（医学）（英德文版）

Summary: The aim of present study was to evaluate the feasibility and efficiency of enhanced green fluorescent protein (EGFP) gene delivery to myocardium in vivo by ultrasound targeted microbubble destruction (UTMD) and polyethylenimine (PEI). SonoVue/DNA and PEI/DNA/SonoVue complexes were prepared. Gel electrophoresis analysis was performed to determine the structural integrity of plasmid DNA or PEI/DNA after UTMD. Solutions of plasmid DNA, SonoVue/DNA, PEI/DNA complexes or PEI/DNA/SonoVue complexes were respectively transduced into BALB/c mice hearts by means of transthoracic ultrasound irradiation. Mice undergoing PBS injection, plasmid injection or PEI/DNA complexes injection without ultrasound irradiation served as controls. Gene expression in myocardium was detected 4 days after treatment. Cryosections and histological examinations were conducted. Electrophoresis gel assay showed no damage to DNA or PEI/DNA complexes after UTMD. When the heart was not exposed to ultrasound, the expression of EGFP was observed in the subendocardial myocardium obviously. The strongest expression was detected in the anterior wall of the left ventricle when the heart was exposed to ultrasound alone. Injection of PEI/DNA complexes and UTMD resulted in the highest transfection efficiency and the distributional difference of EGFP was not obvious. No tissue damage was seen histologically. In conclusion, a combination of UTMD and PEI was highly effective in transfecting mice hearts without causing any apparently adverse effect. It provides an alternative to current clinical gene therapy and opens a new concept of non-viral gene delivery for the treatment of cardiac disease.