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1.
Hum Mol Genet ; 29(23): 3744-3756, 2021 02 04.
Article in English | MEDLINE | ID: mdl-33084871

ABSTRACT

Several X-linked neurodevelopmental disorders including Rett syndrome, induced by mutations in the MECP2 gene, and fragile X syndrome (FXS), caused by mutations in the FMR1 gene, share autism-related features. The mRNA coding for methyl CpG binding protein 2 (MeCP2) has previously been identified as a substrate for the mRNA-binding protein, fragile X mental retardation protein (FMRP), which is silenced in FXS. Here, we report a homeostatic relationship between these two key regulators of gene expression in mouse models of FXS (Fmr1 Knockout (KO)) and Rett syndrome (MeCP2 KO). We found that the level of MeCP2 protein in the cerebral cortex was elevated in Fmr1 KO mice, whereas MeCP2 KO mice displayed reduced levels of FMRP, implicating interplay between the activities of MeCP2 and FMRP. Indeed, knockdown of MeCP2 with short hairpin RNAs led to a reduction of FMRP in mouse Neuro2A and in human HEK-293 cells, suggesting a reciprocal coupling in the expression level of these two regulatory proteins. Intra-cerebroventricular injection of an adeno-associated viral vector coding for FMRP led to a concomitant reduction in MeCP2 expression in vivo and partially corrected locomotor hyperactivity. Additionally, the level of MeCP2 in the posterior cortex correlated with the severity of the hyperactive phenotype in Fmr1 KO mice. These results demonstrate that MeCP2 and FMRP operate within a previously undefined homeostatic relationship. Our findings also suggest that MeCP2 overexpression in Fmr1 KO mouse posterior cerebral cortex may contribute to the fragile X locomotor hyperactivity phenotype.


Subject(s)
Cerebral Cortex/pathology , Disease Models, Animal , Fragile X Mental Retardation Protein/physiology , Fragile X Syndrome/pathology , Gene Expression Regulation , Methyl-CpG-Binding Protein 2/physiology , Phenotype , Animals , Cerebral Cortex/metabolism , Female , Fragile X Syndrome/etiology , Fragile X Syndrome/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout
2.
BMC Cardiovasc Disord ; 22(1): 362, 2022 08 08.
Article in English | MEDLINE | ID: mdl-35941535

ABSTRACT

BACKGROUND: Systemic immune-inflammation index (SII, platelet × neutrophil/lymphocyte ratio), a new marker of inflammation, is associated with adverse cardiovascular events, but its relationship with coronary slow flow phenomenon (CSFP) is unclear. Therefore, we aimed to investigate the relationship between SII and CSFP. METHODS: We enrolled consecutive patients who presented with chest pain, with normal/near-normal coronary angiography findings (n = 89 as CSFP group; n = 167 as control group). The baseline characteristics, laboratory parameters and angiographic characteristics of the two groups were compared. RESULTS: SII levels were significantly higher in the CSFP group than in the control group (409.7 ± 17.7 vs. 396.7 ± 12.7, p < 0.001). A significant positive correlation between SII and the mean thrombolysis in myocardial infarction frame count (mTFC) was found (r = 0.624, p < 0.001). SII increased with the number of coronary arteries involved in CSFP. In multivariate logistic regression analysis, SII/10 was an independent predictor of CSFP (odds ratio: 1.739, p < 0.001). In addition, the SII level > 404.29 was a predictor of CSFP with 67.4% sensitivity and 71.9% specificity. CONCLUSIONS: SII can predict the occurrence of CSFP.


Subject(s)
Myocardial Infarction , No-Reflow Phenomenon , Coronary Angiography , Coronary Vessels/diagnostic imaging , Humans , Inflammation/diagnosis , No-Reflow Phenomenon/diagnostic imaging
3.
Electrophoresis ; 42(9-10): 1070-1078, 2021 05.
Article in English | MEDLINE | ID: mdl-33442876

ABSTRACT

In this work, we aim to observe and study the physics of bacteria and cancer cells pearl chain formation under dielectrophoresis (DEP). Experimentally, we visualized the formation of Bacillus subtilis bacterial pearl chain and human breast cancer cell (MCF-7) chain under positive and negative dielectrophoretic force, respectively. Through a simple simulation with creeping flow, AC/DC electric fields, and particle tracing modules in COMSOL, we examined the mechanism by which bacteria self-organize into a pearl chain across the gap between two electrodes via DEP. Our simulation results reveal that the region of greatest positive DEP force shifts from the electrode edge to the leading edge of the pearl chain, thus guiding the trajectories of free-flowing particles toward the leading edge via positive DEP. Our findings additionally highlight the mechanism why the free-flowing particles are more likely to join the existing pearl chain rather than starting a new pearl chain. This phenomenon is primarily due to the increase in magnitude of electric field gradient, and hence DEP force exerted, with the shortening gap between the pearl chain leading edge and the adjacent electrode. The findings shed light on the observed behavior of preferential pearl chain formation across electrode gaps.


Subject(s)
Bacteria , Cell Line, Tumor , Computer Simulation , Electrodes , Electrophoresis , Equipment Design , Humans , Neoplasms
4.
Micromachines (Basel) ; 15(3)2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38542555

ABSTRACT

Shrink film is a thin sheet of polystyrene plastic that shrinks to 25-40% of its original size when heated. This study investigated the shrinkage factor of the film at different temperatures and baking times to determine the optimal fabrication recipe for shrink film microfluidic device production. Additionally, this study characterized the properties of shrink film, including minimum possible feature size and cross-section geometries, using manual engraving and the CAMEO 4 automated cutting machine. The optimal shrinkage factor ranged from 1.7 to 2.9 at 150 °C and a baking time of 4 min, producing the ideal size for microfluidic device fabrication. The X- and Y-axes shrank ~2.5 times, while Z-axis thickened by a factor of ~5.8 times. This study achieved a minimum feature size of 200 microns, limited by the collapsing of channel sidewalls when shrunk, leading to blockages in the microchannel. These findings demonstrate the feasibility and versatility of using shrink film as a cost-effective and efficient material for the rapid fabrication of microfluidic devices. The potential applications of this material in various fields such as the medical and biomedical industries, bacteria and algae culture and enumeration are noteworthy.

5.
Lab Chip ; 24(15): 3728-3737, 2024 07 23.
Article in English | MEDLINE | ID: mdl-38953748

ABSTRACT

We present the development and validation of an impedance-based urine osmometer for accurate and portable measurement of urine osmolality. The urine osmolality of a urine sample can be estimated by determining the concentrations of the conductive solutes and urea, which make up approximately 94% of the urine composition. Our method utilizes impedance measurements to determine the conductive solutes and urea after hydrolysis with urease enzyme. We built an impedance model using sodium chloride (NaCl) and urea at various known concentrations. In this work, we validated the accuracy of the impedance-based urine osmometer by developing a proof-of-concept first prototype and an integrated urine dipstick second prototype, where both prototypes exhibit an average accuracy of 95.5 ± 2.4% and 89.9 ± 9.1%, respectively in comparison to a clinical freezing point osmometer in the hospital laboratory. While the integrated dipstick design exhibited a slightly lower accuracy than the first prototype, it eliminated the need for pre-mixing or manual pipetting. Impedance calibration curves for conductive and non-conductive solutes consistently yielded results for NaCl but underscored challenges in achieving uniform urease enzyme coating on the dipstick. We also investigated the impact of storing urine at room temperature for 24 hours, demonstrating negligible differences in osmolality values. Overall, our impedance-based urine osmometer presents a promising tool for point-of-care urine osmolality measurements, addressing the demand for a portable, accurate, and user-friendly device with potential applications in clinical and home settings.


Subject(s)
Electric Impedance , Urea , Urease , Urea/urine , Urea/chemistry , Osmolar Concentration , Hydrolysis , Humans , Urease/metabolism , Urease/chemistry , Urinalysis/instrumentation , Equipment Design
6.
BMJ Open ; 14(6): e079212, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38858161

ABSTRACT

INTRODUCTION: Severe septic cardiomyopathy (SCM) is one of the main causes of refractory septic shock (RSS), with a high mortality. The application of venoarterial extracorporeal membrane oxygenation (ECMO) to support the impaired cardiac function in patients with septic shock remains controversial. Moreover, no prospective studies have been taken to address whether venoarterial ECMO treatment could improve the outcome of patients with sepsis-induced cardiogenic shock. The objective of this study is to assess whether venoarterial ECMO treatment can improve the 30-day survival rate of patients with sepsis-induced refractory cardiogenic shock. METHODS AND ANALYSIS: ExtraCorporeal Membrane Oxygenation in the therapy for REfractory Septic shock with Cardiac function Under Estimated is a prospective, multicentre, non-randomised, cohort study on the application of ECMO in SCM. At least 64 patients with SCM and RSS will be enrolled in an estimated ratio of 1:1.5. Participants taking venoarterial ECMO during the period of study are referred to as cohort 1, and patients receiving only conventional therapy without ECMO belong to cohort 2. The primary outcome is survival in a 30-day follow-up period. Other end points include survival to intensive care unit (ICU) discharge, hospital survival, 6-month survival, quality of life for long-term survival (EQ-5D score), successful rate of ECMO weaning, long-term survivors' cardiac function, the number of days alive without continuous renal replacement therapy, mechanical ventilation and vasopressor, ICU and hospital length of stay, the rate of complications potentially related to ECMO treatment. ETHICS AND DISSEMINATION: The trial has been approved by the Clinical Research and Application Institutional Review Board of the Second Affiliated Hospital of Guangzhou Medical University (2020-hs-51). Participants will be screened and enrolled from ICU patients with septic shock by clinicians, with no public advertisement for recruitment. Results will be disseminated in research journals and through conference presentations. TRIAL REGISTRATION NUMBER: NCT05184296.


Subject(s)
Extracorporeal Membrane Oxygenation , Shock, Cardiogenic , Shock, Septic , Adult , Female , Humans , Male , Cardiomyopathies/therapy , Extracorporeal Membrane Oxygenation/methods , Intensive Care Units , Multicenter Studies as Topic , Prospective Studies , Shock, Cardiogenic/therapy , Shock, Cardiogenic/mortality , Shock, Septic/therapy , Shock, Septic/mortality , Shock, Septic/complications , Survival Rate
7.
Signal Transduct Target Ther ; 9(1): 215, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39134529

ABSTRACT

Dual inhibition of vascular endothelial growth factor and epidermal growth factor receptor (EGFR) signaling pathways offers the prospect of improving the effectiveness of EFGR-targeted therapy. In this phase 3 study (ClinicalTrial.gov: NCT04028778), 315 patients with treatment-naïve, EGFR-mutated, advanced non-small cell lung cancer (NSCLC) were randomized (1:1) to receive anlotinib or placebo plus gefitinib once daily on days 1-14 per a 3-week cycle. At the prespecified final analysis of progression-free survival (PFS), a significant improvement in PFS was observed for the anlotinib arm over the placebo arm (hazards ratio [HR] = 0.64, 95% CI, 0.48-0.80, P = 0.003). Particularly, patients with brain metastasis and those harboring EGFR amplification or high tumor mutation load gained significant more benefits in PFS from gefitinib plus anlotinib. The incidence of grade 3 or higher treatment-emergent adverse events was 49.7% of the patients receiving gefitinib plus anlotinib versus 31.0% of the patients receiving gefitinib plus placebo. Anlotinib plus gefitinib significantly improves PFS in patients with treatment-naïve, EGFR-mutated, advanced NSCLC, with a manageable safety profile.


Subject(s)
Carcinoma, Non-Small-Cell Lung , ErbB Receptors , Gefitinib , Indoles , Lung Neoplasms , Mutation , Protein Kinase Inhibitors , Quinolines , Humans , Gefitinib/administration & dosage , Gefitinib/adverse effects , Gefitinib/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Quinolines/administration & dosage , Quinolines/adverse effects , Quinolines/therapeutic use , Indoles/administration & dosage , Indoles/therapeutic use , Indoles/adverse effects , Male , Female , ErbB Receptors/genetics , ErbB Receptors/antagonists & inhibitors , Middle Aged , Aged , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Protein Kinase Inhibitors/adverse effects , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Adult , Aged, 80 and over
8.
Wei Sheng Yan Jiu ; 42(1): 6-9, 2013 Jan.
Article in Zh | MEDLINE | ID: mdl-23596699

ABSTRACT

OBJECTIVE: To investigate whether curcumin intake could improve kidney, liver pathological changes in type 2 diabetes (T2DM) rats. METHODS: 100 male Wistar rats were randomly divided into two groups: 10 rats in the control group; 90 in the T2DM model rats, the using low-dose treptozotocin (30 mg/kg BW) combined high sugar and high fat diet to induce T2DM model. After the success of the model induction, 39 T2DM rats met the selection criteria, which were randomly divided into 4 groups: T2DM model control group, low-dose curcumin group (50 mg/kg BW), curcumin dose group (150 mg/kg BW) and curcumin high-dose group (250 mg/kg BW), given intervention. After 45 days treatment, rats from each group were randomly selected four for pathological testing and observation of kidney and liver changes. RESULTS: Compared with the control group, the results showed that blood glucose and lipids in T2DM model group were significantly increased (P < 0.05). Compared to the T2DM control group, curcumin treatment significant improved kidney and liver pathological changes. CONCLUSION: Curcumin can improve liver and kidney pathological changes in T2DM rats.


Subject(s)
Curcumin/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Kidney/pathology , Liver/pathology , Animals , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 2/pathology , Male , Rats , Rats, Wistar
9.
Nat Cancer ; 4(10): 1418-1436, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37697045

ABSTRACT

Glioblastoma (GBM) is an incurable brain cancer that lacks effective therapies. Here we show that EAG2 and Kvß2, which are predominantly expressed by GBM cells at the tumor-brain interface, physically interact to form a potassium channel complex due to a GBM-enriched Kvß2 isoform. In GBM cells, EAG2 localizes at neuron-contacting regions in a Kvß2-dependent manner. Genetic knockdown of the EAG2-Kvß2 complex decreases calcium transients of GBM cells, suppresses tumor growth and invasion and extends the survival of tumor-bearing mice. We engineered a designer peptide to disrupt EAG2-Kvß2 interaction, thereby mitigating tumor growth in patient-derived xenograft and syngeneic mouse models across GBM subtypes without overt toxicity. Neurons upregulate chemoresistant genes in GBM cells in an EAG2-Kvß2-dependent manner. The designer peptide targets neuron-associated GBM cells and possesses robust efficacy in treating temozolomide-resistant GBM. Our findings may lead to the next-generation therapeutic agent to benefit patients with GBM.


Subject(s)
Glioblastoma , Humans , Mice , Animals , Glioblastoma/drug therapy , Temozolomide/pharmacology , Temozolomide/therapeutic use , Ether-A-Go-Go Potassium Channels/therapeutic use , Disease Models, Animal , Peptides/therapeutic use , Neurons/pathology
10.
Micromachines (Basel) ; 13(8)2022 Jul 28.
Article in English | MEDLINE | ID: mdl-36014121

ABSTRACT

In this article, we present a microfluidic technique for the rapid enumeration of bacterial density with a syringe filter to trap bacteria and the quantification of the bacterial density through pressure difference measurement across the membrane. First, we established the baseline differential pressure and hydraulic resistance for a filtration membrane by fully wetting the filter with DI water. Subsequently, when bacteria were infused and trapped at the pores of the membrane, the differential pressure and hydraulic resistance also increased. We characterized the infusion time required for the bacterial sample to achieve a normalized hydraulic resistance of 1.5. An equivalent electric-circuit model and calibration data sets from parametric studies were used to determine the general form of a calibration curve for the prediction of the bacterial density of a bacterial sample. As a proof of concept, we demonstrated through blind tests with Escherichia coli that the device is capable of determining the bacterial density of a sample ranging from 7.3 × 106 to 2.2 × 108 CFU/mL with mean and median accuracies of 87.21% and 91.33%, respectively. The sample-to-result time is 19 min for a sample with lower detection threshold, while for higher-bacterial-density samples the measurement time is further shortened to merely 8 min.

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