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1.
Nature ; 614(7946): 88-94, 2023 02.
Article in English | MEDLINE | ID: mdl-36653458

ABSTRACT

Two-dimensional (2D) materials and their heterostructures show a promising path for next-generation electronics1-3. Nevertheless, 2D-based electronics have not been commercialized, owing mainly to three critical challenges: i) precise kinetic control of layer-by-layer 2D material growth, ii) maintaining a single domain during the growth, and iii) wafer-scale controllability of layer numbers and crystallinity. Here we introduce a deterministic, confined-growth technique that can tackle these three issues simultaneously, thus obtaining wafer-scale single-domain 2D monolayer arrays and their heterostructures on arbitrary substrates. We geometrically confine the growth of the first set of nuclei by defining a selective growth area via patterning SiO2 masks on two-inch substrates. Owing to substantial reduction of the growth duration at the micrometre-scale SiO2 trenches, we obtain wafer-scale single-domain monolayer WSe2 arrays on the arbitrary substrates by filling the trenches via short growth of the first set of nuclei, before the second set of nuclei is introduced, thus without requiring epitaxial seeding. Further growth of transition metal dichalcogenides with the same principle yields the formation of single-domain MoS2/WSe2 heterostructures. Our achievement will lay a strong foundation for 2D materials to fit into industrial settings.

2.
Nature ; 578(7793): 75-81, 2020 02.
Article in English | MEDLINE | ID: mdl-32025010

ABSTRACT

Complex-oxide materials exhibit a vast range of functional properties desirable for next-generation electronic, spintronic, magnetoelectric, neuromorphic, and energy conversion storage devices1-4. Their physical functionalities can be coupled by stacking layers of such materials to create heterostructures and can be further boosted by applying strain5-7. The predominant method for heterogeneous integration and application of strain has been through heteroepitaxy, which drastically limits the possible material combinations and the ability to integrate complex oxides with mature semiconductor technologies. Moreover, key physical properties of complex-oxide thin films, such as piezoelectricity and magnetostriction, are severely reduced by the substrate clamping effect. Here we demonstrate a universal mechanical exfoliation method of producing freestanding single-crystalline membranes made from a wide range of complex-oxide materials including perovskite, spinel and garnet crystal structures with varying crystallographic orientations. In addition, we create artificial heterostructures and hybridize their physical properties by directly stacking such freestanding membranes with different crystal structures and orientations, which is not possible using conventional methods. Our results establish a platform for stacking and coupling three-dimensional structures, akin to two-dimensional material-based heterostructures, for enhancing device functionalities8,9.

3.
Nano Lett ; 24(10): 2939-2952, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38477054

ABSTRACT

Advanced heterogeneous integration technologies are pivotal for next-generation electronics. Single-crystalline materials are one of the key building blocks for heterogeneous integration, although it is challenging to produce and integrate these materials. Remote epitaxy is recently introduced as a solution for growing single-crystalline thin films that can be exfoliated from host wafers and then transferred onto foreign platforms. This technology has quickly gained attention, as it can be applied to a wide variety of materials and can realize new functionalities and novel application platforms. Nevertheless, remote epitaxy is a delicate process, and thus, successful execution of remote epitaxy is often challenging. Here, we elucidate the mechanisms of remote epitaxy, summarize recent breakthroughs, and discuss the challenges and solutions in the remote epitaxy of various material systems. We also provide a vision for the future of remote epitaxy for studying fundamental materials science, as well as for functional applications.

4.
Circulation ; 147(24): 1823-1842, 2023 06 13.
Article in English | MEDLINE | ID: mdl-37158107

ABSTRACT

BACKGROUND: Shortly after birth, cardiomyocytes exit the cell cycle and cease proliferation. At present, the regulatory mechanisms for this loss of proliferative capacity are poorly understood. CBX7 (chromobox 7), a polycomb group (PcG) protein, regulates the cell cycle, but its role in cardiomyocyte proliferation is unknown. METHODS: We profiled CBX7 expression in the mouse hearts through quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry. We overexpressed CBX7 in neonatal mouse cardiomyocytes through adenoviral transduction. We knocked down CBX7 by using constitutive and inducible conditional knockout mice (Tnnt2-Cre;Cbx7fl/+ and Myh6-MCM;Cbx7fl/fl, respectively). We measured cardiomyocyte proliferation by immunostaining of proliferation markers such as Ki67, phospho-histone 3, and cyclin B1. To examine the role of CBX7 in cardiac regeneration, we used neonatal cardiac apical resection and adult myocardial infarction models. We examined the mechanism of CBX7-mediated repression of cardiomyocyte proliferation through coimmunoprecipitation, mass spectrometry, and other molecular techniques. RESULTS: We explored Cbx7 expression in the heart and found that mRNA expression abruptly increased after birth and was sustained throughout adulthood. Overexpression of CBX7 through adenoviral transduction reduced proliferation of neonatal cardiomyocytes and promoted their multinucleation. On the other hand, genetic inactivation of Cbx7 increased proliferation of cardiomyocytes and impeded cardiac maturation during postnatal heart growth. Genetic ablation of Cbx7 promoted regeneration of neonatal and adult injured hearts. Mechanistically, CBX7 interacted with TARDBP (TAR DNA-binding protein 43) and positively regulated its downstream target, RBM38 (RNA Binding Motif Protein 38), in a TARDBP-dependent manner. Overexpression of RBM38 inhibited the proliferation of CBX7-depleted neonatal cardiomyocytes. CONCLUSIONS: Our results demonstrate that CBX7 directs the cell cycle exit of cardiomyocytes during the postnatal period by regulating its downstream targets TARDBP and RBM38. This is the first study to demonstrate the role of CBX7 in regulation of cardiomyocyte proliferation, and CBX7 could be an important target for cardiac regeneration.


Subject(s)
DNA-Binding Proteins , Myocytes, Cardiac , Animals , Mice , Animals, Newborn , Cell Proliferation , DNA-Binding Proteins/metabolism , Mice, Knockout , Myocytes, Cardiac/metabolism , Polycomb-Group Proteins/metabolism
5.
Nat Mater ; 22(12): 1470-1477, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38012388

ABSTRACT

Three-dimensional (3D) hetero-integration technology is poised to revolutionize the field of electronics by stacking functional layers vertically, thereby creating novel 3D circuity architectures with high integration density and unparalleled multifunctionality. However, the conventional 3D integration technique involves complex wafer processing and intricate interlayer wiring. Here we demonstrate monolithic 3D integration of two-dimensional, material-based artificial intelligence (AI)-processing hardware with ultimate integrability and multifunctionality. A total of six layers of transistor and memristor arrays were vertically integrated into a 3D nanosystem to perform AI tasks, by peeling and stacking of AI processing layers made from bottom-up synthesized two-dimensional materials. This fully monolithic-3D-integrated AI system substantially reduces processing time, voltage drops, latency and footprint due to its densely packed AI processing layers with dense interlayer connectivity. The successful demonstration of this monolithic-3D-integrated AI system will not only provide a material-level solution for hetero-integration of electronics, but also pave the way for unprecedented multifunctional computing hardware with ultimate parallelism.

6.
J Gastroenterol Hepatol ; 39(2): 392-398, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37941163

ABSTRACT

BACKGROUND AND AIM: Decreased kidney function is a putative risk factor for various cancers. However, few studies have investigated the association between a decreased estimated glomerular filtration rate (eGFR) and incident pancreatic cancer. We aimed to investigate the risk of incident pancreatic cancer according to eGFR categories. METHODS: In this retrospective cohort study, we included 359 721 adults who underwent health checkups in 2009 or 2010 by using the Korean National Health Insurance Database. The study population was categorized into four groups by eGFR (mL/min/1.73 m2 ) using the Chronic Kidney Disease Epidemiology Collaboration equation: group 1 (eGFR < 45), group 2 (eGFR ≥ 45 to < 60), group 3 (eGFR ≥ 60 to < 90), and group 4 (eGFR ≥ 90). Multivariate Cox proportional hazards models were used to determine the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of pancreatic cancer until 2019 by comparing the eGFR groups. RESULTS: During the 3 493 589.05 person-years of follow-up, 1702 pancreatic cancer cases were identified. Compared with group 4 (eGFR ≥ 90), HRs and 95% CIs for the incidence of pancreatic cancer were 1.39 (1.24-1.56) for group 3 (eGFR ≥ 60 to < 90), 1.79 (1.47-2.16) for group 2 (eGFR ≥ 45 to < 60), and 2.05 (1.62-2.60) for group 1 (eGFR < 45) in the multivariate adjusted model. CONCLUSIONS: Decreased eGFR was significantly associated with an increased risk of pancreatic cancer in Korean population. Further studies are needed to investigate the relationship between a decreased eGFR and the risk of pancreatic cancer in other ethnic groups.


Subject(s)
Pancreatic Neoplasms , Renal Insufficiency, Chronic , Adult , Humans , Glomerular Filtration Rate , Retrospective Studies , Renal Insufficiency, Chronic/epidemiology , Risk Factors , Pancreatic Neoplasms/etiology , Pancreatic Neoplasms/complications
7.
BMC Nephrol ; 25(1): 142, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38649936

ABSTRACT

BACKGROUND: IgA nephropathy (IgAN) is the most common type of primary glomerulonephritis, although the definitive markers are unknown. We aimed to investigate the clinical significance of urinary cytokines in patients with IgAN. METHODS: From 2009 to 2018, the patients were divided into three groups: IgAN (n = 191), disease control (n = 53), and normal control (n = 76). We used a multiplex enzyme-linked immunosorbent assay to measure 16 selected urinary inflammatory cytokines, evaluated the correlation between clinical and pathological features following regression analysis on progression. RESULTS: The IgAN group exhibited significantly different levels of urinary cytokines compared to the normal control and disease control groups. Urinary levels of B-cell-activating factor, vascular endothelial growth factor receptor-2, monocyte chemoattractant protein-1, C-X-C motif chemokine 10, C-X-C motif ligand 16, epidermal growth factor (EGF), endocan, endostatin, growth/differentiation factor-15 (GDF-15), interleukin-6 (IL-6), mannose-binding lectin, transferrin receptor, and kidney injury molecule-1 were significantly correlated with both the estimated glomerular filtration rate and urine protein-creatinine ratio. In a multivariate Cox regression analysis, urinary EGF (hazard ratio [HR] 0.40, 95% confidence interval [CI] 0.17-0.95, P = 0.04), GDF-15 (HR 2.45, 95% CI 1.01-5.94, P = 0.048), and IL-6 (HR 3.02, 95% CI 1.05-8.64, P = 0.04) were associated with progression in IgAN. CONCLUSIONS: Urinary inflammatory biomarkers may serve as alternative predictive biomarkers in patients with IgAN. Further studies are needed to elucidate the physiological mechanisms and confirm the results.


Subject(s)
Biomarkers , Cytokines , Glomerulonephritis, IGA , Humans , Glomerulonephritis, IGA/urine , Glomerulonephritis, IGA/diagnosis , Male , Female , Biomarkers/urine , Adult , Cytokines/urine , Middle Aged , Glomerular Filtration Rate , Disease Progression , Epidermal Growth Factor/urine , Clinical Relevance
8.
J Am Soc Nephrol ; 34(5): 857-875, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36720675

ABSTRACT

SIGNIFICANCE STATEMENT: eGFR slope has been used as a surrogate outcome for progression of CKD. However, genetic markers associated with eGFR slope among patients with CKD were unknown. We aimed to identify genetic susceptibility loci associated with eGFR slope. A two-phase genome-wide association study identified single nucleotide polymorphisms (SNPs) in TPPP and FAT1-LINC02374 , and 22 of them were used to derive polygenic risk scores that mark the decline of eGFR by disrupting binding of nearby transcription factors. This work is the first to identify the impact of TPPP and FAT1-LINC02374 on CKD progression, providing predictive markers for the decline of eGFR in patients with CKD. BACKGROUND: The incidence of CKD is associated with genetic factors. However, genetic markers associated with the progression of CKD have not been fully elucidated. METHODS: We conducted a genome-wide association study among 1738 patients with CKD, mainly from the KoreaN cohort study for Outcomes in patients With CKD. The outcome was eGFR slope. We performed a replication study for discovered single nucleotide polymorphisms (SNPs) with P <10 -6 in 2498 patients with CKD from the Chronic Renal Insufficiency Cohort study. Several expression quantitative trait loci (eQTL) studies, pathway enrichment analyses, exploration of epigenetic architecture, and predicting disruption of transcription factor (TF) binding sites explored potential biological implications of the loci. We developed and evaluated the effect of polygenic risk scores (PRS) on incident CKD outcomes. RESULTS: SNPs in two novel loci, TPPP and FAT1-LINC02374 , were replicated (rs59402340 in TPPP , Pdiscovery =7.11×10 -7 , PCRIC =8.13×10 -4 , Pmeta =7.23×10 -8 ; rs28629773 in FAT1-LINC02374 , Pdiscovery =6.08×10 -7 , PCRIC =4.33×10 -2 , Pmeta =1.87×10 -7 ). The eQTL studies revealed that the replicated SNPs regulated the expression level of nearby genes associated with kidney function. Furthermore, these SNPs were near gene enhancer regions and predicted to disrupt the binding of TFs. PRS based on the independently significant top 22 SNPs were significantly associated with CKD outcomes. CONCLUSIONS: This study demonstrates that SNP markers in the TPPP and FAT1-LINC02374 loci could be predictive markers for the decline of eGFR in patients with CKD.


Subject(s)
Genome-Wide Association Study , Renal Insufficiency, Chronic , Humans , Cohort Studies , Genetic Markers , Renal Insufficiency, Chronic/genetics , Quantitative Trait Loci , Polymorphism, Single Nucleotide , Disease Progression , Genetic Predisposition to Disease
9.
J Cutan Med Surg ; : 12034754241256347, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38783539

ABSTRACT

BACKGROUND/OBJECTIVES: Actinic keratoses (AK) are premalignant skin lesions caused by chronic sun exposure, topically managed by 5-fluorouracil (5-FU), diclofenac 3% gel, and imiquimod. Despite their effectiveness, long treatment duration and severe adverse local skin reactions have limited patient concordance. Calcipotriol has recently been used as a combination agent for existing topical AK treatments. A systematic review was performed to determine the clinical efficacy of 5-FU and calcipotriol for the treatment of AK, Bowen's disease, and squamous cell carcinoma (SCC). METHODS: A systematic literature search was conducted on Medline, Embase, and Cochrane Library. Among the 84 records screened, 12 were retrieved for full-text review and 8 were included in the final analysis. RESULTS: Among the 8 studies, there were 214 control patients and 288 patients who received the intervention. The combination 5% 5-FU with calcipotriol resulted in a significant reduction in the number of AKs on the face, scalp, right upper extremity, and left upper extremity for all sites at 8 weeks (P < .0001). No significant difference in SCC incidence was observed at 1 or 2 years, but there was a significant reduction observed at 3 years for SCC on face and scalp. No study assessed the combination for Bowen's disease. CONCLUSIONS: Combination 5% 5-FU with calcipotriol is an effective treatment for Aks; however, future trials may consider longer treatment and follow-up periods for the treatment and prevention of AK, SCC in situ, and SCC.

10.
Int J Mol Sci ; 25(10)2024 May 09.
Article in English | MEDLINE | ID: mdl-38791177

ABSTRACT

Acute rejection (AR) is critical for long-term graft survival in kidney transplant recipients (KTRs). This study aimed to evaluate the efficacy of the integrated risk score of omics-based biomarkers in predicting AR in KTRs. This prospective, randomized, controlled, multicenter, pilot study enrolled 40 patients who recently underwent high-immunologic-risk kidney transplantation (KT). Five omics biomarkers were measured, namely, blood mRNA (three-gene signature), urinary exosomal miRNA (three-gene signature), urinary mRNA (six-gene signature), and two urinary exosomal proteins (hemopexin and tetraspanin-1) at 2 weeks and every 4 weeks after KT for 1 year. An integrated risk score was generated by summing each biomarker up. The biomarker group was informed about the integrated risk scores and used to adjust immunosuppression, but not the control group. The outcomes were graft function and frequency of graft biopsy. Sixteen patients in the biomarker group and nineteen in the control group completed the study. The mean estimated glomerular filtration rate after KT did not differ between the groups. Graft biopsy was performed in two patients (12.5%) and nine (47.4%) in the biomarker and control groups, respectively, with the proportion being significantly lower in the biomarker group (p = 0.027). One patient (6.3%) in the biomarker group and two (10.5%) in the control group were diagnosed with AR, and the AR incidence did not differ between the groups. The tacrolimus trough level was significantly lower in the biomarker group than in the control group at 1 year after KT (p = 0.006). Integrated omics biomarker monitoring may help prevent unnecessary or high-complication-risk biopsy and enables tailored immunosuppression by predicting the risk of AR in KTRs.


Subject(s)
Biomarkers , Graft Rejection , Kidney Transplantation , Humans , Kidney Transplantation/adverse effects , Graft Rejection/diagnosis , Graft Rejection/blood , Male , Female , Biomarkers/blood , Biomarkers/urine , Pilot Projects , Middle Aged , Prospective Studies , Adult , Risk Factors , Graft Survival , MicroRNAs/blood , MicroRNAs/genetics , Risk Assessment
11.
Int J Mol Sci ; 25(8)2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38674120

ABSTRACT

Hematopoietic acute radiation syndrome (H-ARS) involves injury to multiple organ systems following total body irradiation (TBI). Our laboratory demonstrated that captopril, an angiotensin-converting enzyme inhibitor, mitigates H-ARS in Göttingen minipigs, with improved survival and hematopoietic recovery, as well as the suppression of acute inflammation. However, the effects of captopril on the gastrointestinal (GI) system after TBI are not well known. We used a Göttingen minipig H-ARS model to investigate captopril's effects on the GI following TBI (60Co 1.79 or 1.80 Gy, 0.42-0.48 Gy/min), with endpoints at 6 or 35 days. The vehicle or captopril (0.96 mg/kg) was administered orally twice daily for 12 days, starting 4 h post-irradiation. Ilea were harvested for histological, protein, and RNA analyses. TBI increased congestion and mucosa erosion and hemorrhage, which were modulated by captopril. GPX-4 and SLC7A11 were downregulated post-irradiation, consistent with ferroptosis at 6 and 35 days post-irradiation in all groups. Interestingly, p21/waf1 increased at 6 days in vehicle-treated but not captopril-treated animals. An RT-qPCR analysis showed that radiation increased the gene expression of inflammatory cytokines IL1B, TNFA, CCL2, IL18, and CXCL8, and the inflammasome component NLRP3. Captopril suppressed radiation-induced IL1B and TNFA. Rectal microbiome analysis showed that 1 day of captopril treatment with radiation decreased overall diversity, with increased Proteobacteria phyla and Escherichia genera. By 6 days, captopril increased the relative abundance of Enterococcus, previously associated with improved H-ARS survival in mice. Our data suggest that captopril mitigates senescence, some inflammation, and microbiome alterations, but not ferroptosis markers in the intestine following TBI.


Subject(s)
Acute Radiation Syndrome , Captopril , Disease Models, Animal , Ferroptosis , Gastrointestinal Microbiome , Inflammation , Swine, Miniature , Whole-Body Irradiation , Animals , Acute Radiation Syndrome/drug therapy , Swine , Inflammation/pathology , Captopril/pharmacology , Whole-Body Irradiation/adverse effects , Ferroptosis/drug effects , Gastrointestinal Microbiome/drug effects , Intestines/microbiology , Intestines/pathology , Intestines/drug effects , Intestines/radiation effects , Male , Angiotensin-Converting Enzyme Inhibitors/pharmacology
12.
Medicina (Kaunas) ; 60(6)2024 May 28.
Article in English | MEDLINE | ID: mdl-38929499

ABSTRACT

Background and Objectives: Acetabular fractures, though infrequent, present considerable challenges in treatment due to their association with high-energy trauma and poor prognoses. Posterior wall fractures, the most common type among them, typically have a more favorable prognosis compared to other types. Anatomical reduction and stable fixation of the posterior wall are crucial for optimal treatment outcomes. This study aimed to biomechanically compare three commonly used fixation methods for posterior wall fractures of the acetabulum-a conventional reconstruction plate, a spring plate, and a 2.7 mm variable angle locking compression plate (VA-LCP). Materials and Methods: The study utilized 6 fresh-frozen cadavers, yielding 12 hemipelvises free from prior trauma or surgery. Three fixation methods were compared using a simple acetabulum posterior wall fracture model. Fixation was performed by an orthopedic specialist, with prebending of plates to minimize errors. Hemipelvises were subjected to quasi-static and cyclic loading tests, measuring fracture gap, stiffness, and displacement under load. Results: It showed no significant differences in fracture gap among the three fixation methods under cyclic loading conditions simulating walking. However, the conventional reconstruction plate exhibited a greater stiffness compared to the spring and variable angle plates. Fatigue analysis revealed no significant differences among the plates, indicating a similar stability throughout cyclic loading. Despite differences in stiffness, all three fixation methods demonstrated adequate stability under loading conditions. Conclusions: While the conventional reconstruction plate demonstrated a superior stiffness, all three fixation methods provided sufficient stability under cyclic loading conditions similar to walking. This suggests that postoperative limitations are unlikely with any of the three methods, provided excessive activities are avoided. Furthermore, the variable angle plate-like the spring plate-offers an appropriate stability for fragment-specific fixation, supporting its use in surgical applications. These findings contribute to understanding the biomechanical performance of different fixation methods for acetabular fractures, facilitating improved surgical outcomes in challenging cases.


Subject(s)
Acetabulum , Bone Plates , Cadaver , Fracture Fixation, Internal , Fractures, Bone , Humans , Acetabulum/injuries , Acetabulum/surgery , Biomechanical Phenomena , Fracture Fixation, Internal/methods , Fracture Fixation, Internal/instrumentation , Fractures, Bone/surgery , Male , Female , Aged , Middle Aged
13.
J Infect Dis ; 227(10): 1185-1193, 2023 05 12.
Article in English | MEDLINE | ID: mdl-36374933

ABSTRACT

BACKGROUND: Urine exosomal bkv-miR-B1-5p is associated with BK virus (BKV) nephropathy (BKVN); however, its posttransplantation changes and predictability for BKVN have not been determined in kidney transplant recipients (KTRs). METHODS: Urine exosomal bkv-miR-B1-5p and urine and plasma BKV DNA were measured at 2 weeks and 3, 6, and 12 months posttransplant in 83 KTRs stratified into biopsy-proven or presumptive BKVN, BKV viruria, and no evidence of BKV reactivation. Joint model, multivariable Cox model and receiver operating characteristic curve (ROC) were used to investigate the association of each assay with the following events: a composite of biopsy-proven or presumptive BKVN, and biopsy-proven BKVN. RESULTS: Urine exosomal bkv-miR-B1-5p and urine and plasma BKV DNA showed similar posttransplant time-course changes. Joint models incorporating serial values demonstrated significant associations of all assays with the events, and Cox analyses using single time point values at 2 weeks posttransplant showed that only urine exosomal bkv-miR-B1-5p was significantly associated with the events, although it did not outperform urine BKV DNA in ROC analyses. CONCLUSIONS: Urine exosomal bkv-miR-B1-5p was associated with BKVN as were urine and plasma BKV DNA loads on serial follow-up, and might have potential as a predictive marker for BKVN during the early posttransplant period. CLINICAL TRIALS REGISTRATION: Clinical Research Information Service (https://cris.nih.go.kr/cris/), KCT0001010.


Subject(s)
BK Virus , Kidney Diseases , Kidney Transplantation , MicroRNAs , Polyomavirus Infections , Tumor Virus Infections , Humans , DNA, Viral , Kidney Diseases/complications , Kidney Transplantation/adverse effects , Polyomavirus Infections/diagnosis , Transplant Recipients
14.
J Mol Cell Cardiol ; 180: 22-32, 2023 07.
Article in English | MEDLINE | ID: mdl-37080451

ABSTRACT

Ischemic cardiovascular disease still remains as a leading cause of morbidity and mortality despite various medical, surgical, and interventional therapy. As such, cell therapy has emerged as an attractive option because it tackles underlying problem of the diseases by inducing neovascularization in ischemic tissue. After overall failure of adult stem or progenitor cells, studies attempted to generate endothelial cells (ECs) from pluripotent stem cells (PSCs). While endothelial cells (ECs) differentiated from PSCs successfully induced vascular regeneration, differentiating volatility and tumorigenic potential is a concern for their clinical applications. Alternatively, direct reprogramming strategies employ lineage-specific factors to change cell fate without achieving pluripotency. ECs have been successfully reprogrammed via ectopic expression of transcription factors (TFs) from endothelial lineage. The reprogrammed ECs induced neovascularization in vitro and in vivo and thus demonstrated their therapeutic value in animal models of vascular insufficiency. Methods of delivering reprogramming factors include lentiviral or retroviral vectors and more clinically relevant, non-integrative adenoviral and episomal vectors. Most studies made use of fibroblast as a source cell for reprogramming, but reprogrammability of other clinically relevant source cell types has to be evaluated. Specific mechanisms and small molecules that are involved in the aforementioned processes tackles challenges associated with direct reprogramming efficiency and maintenance of reprogrammed EC characteristics. After all, this review provides summary of past and contemporary methods of direct endothelial reprogramming and discusses the future direction to overcome these challenges to acquire clinically applicable reprogrammed ECs.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Animals , Endothelial Cells/metabolism , Induced Pluripotent Stem Cells/metabolism , Cell Differentiation/genetics , Fibroblasts , Ischemia/metabolism , Cellular Reprogramming/genetics
15.
Diabetes Metab Res Rev ; 39(8): e3697, 2023 11.
Article in English | MEDLINE | ID: mdl-37653691

ABSTRACT

BACKGROUND: Smoking is a definite risk factor for macrovascular complications in diabetes mellitus (DM). However, the effect of smoking on microvascular complications is inconclusive. METHOD: Study participants were 26,673 diabetic men who received health check-up both in 2003-2004 and 2009, excluding women. Assessing smoking status (never, quitting and current) at 2003-2004 and 2009, changes in smoking status were categorised into 7 groups (never - never, never - quitting, never - current, quitting-quitting, quitting-current, current-quitting and current-current). Smoking amount was categorised into never, light (0-10 pack years), moderate (10-20 pack years), and heavy smoking (>20 pack years) based on 2009 data. They were followed-up until 2013 to identify incident microvascular complications. We calculated the adjusted hazard ratios (HR) and 95% confidence interval (CI) (adjusted HR [95% CI]) for incident microvascular complications according to changes in smoking status and smoking amount. RESULTS: Current-quitting (1.271 [1.050-1.538]), current-current (1.243 [1.070-1.444]) and heavy smoking (1.238 [1.078-1.422]) were associated with an increased risk of overall microvascular complications. The risk of nephropathy increased in current-current smoking (1.429 [1.098-1.860]) and heavy smoking (1.357 [1.061-1.734]). An increased risk of neuropathy was observed in current-quitting smoking (1.360 [1.076-1.719]), current-current smoking (1.237 [1.025-1.492]) and heavy smoking (1.246 [1.048-1.481]). However, we couldn't see the interpretable findings for the association between smoking and retinopathy. CONCLUSIONS: Lasting and heavy smoking increases the risk of microvascular complications, including nephropathy and neuropathy. Quitting smoking and reducing smoking amount are imperative in preventing microvascular complications in DM patients.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetic Angiopathies , Male , Humans , Female , Smoking/adverse effects , Smoking/epidemiology , Risk Factors , Diabetes Mellitus, Type 2/complications , Diabetic Angiopathies/epidemiology , Diabetic Angiopathies/etiology , Proportional Hazards Models
16.
FASEB J ; 36(5): e22272, 2022 05.
Article in English | MEDLINE | ID: mdl-35436011

ABSTRACT

The transition of fibroblasts into myofibroblasts is a crucial step in kidney fibrosis. However, the biological processes involved in this transdifferentiation are incompletely understood. In this study, we discovered that the midbody plays a role in the fibroblast-myofibroblast transition by mediating TGF-ß/Smad signaling. Combining bulk RNA-seq, histology, and the western blot of unilateral ureteral obstruction kidneys, we demonstrated that the pathway related to microtubules is implicated in kidney fibrosis, and the blocking of microtubule dynamics by colchicine improved kidney fibrosis. Subsequently, to explore microtubule-based organelles in detail, we cultured NRK-49F (rat kidney fibroblast cell line) and HKC-8 (human proximal tubule cell line) under transforming growth factor-ß1 (TGF-ß1) stimulation, which caused deciliation in both cell lines during epithelial-mesenchymal and fibroblast-myofibroblast transition. We identified another microtubule-based organelle, the midbody, whose formation is promoted by TGF-ß1 in fibroblasts as a result of proliferation in contrast to tubular cells. Notably, TGF-ß receptors were present in the midbody of both cell lines. In TGF-ß1-treated fibroblasts, colchicine or Hedgehog pathway inhibitor 4 impaired the midbody formation, and attenuated the upregulation of canonical TGF-ß/Smad signaling and α-SMA expression. These findings offer novel insight into the midbody as an active organelle involved in fibroblast-myofibroblast transition by mediating TGF-ß/Smad signaling, which could be a potential therapeutic target.


Subject(s)
Kidney Diseases , Myofibroblasts , Animals , Colchicine/pharmacology , Epithelial-Mesenchymal Transition , Female , Fibroblasts/metabolism , Fibrosis , Hedgehog Proteins/metabolism , Humans , Kidney Diseases/pathology , Male , Myofibroblasts/metabolism , Rats , Signal Transduction/physiology , Transforming Growth Factor beta1/metabolism
17.
Br J Anaesth ; 130(1): e106-e118, 2023 01.
Article in English | MEDLINE | ID: mdl-35995638

ABSTRACT

BACKGROUND: Airway driving pressure, easily measured as plateau pressure minus PEEP, is a surrogate for alveolar stress and strain. However, the effect of its targeted reduction remains unclear. METHODS: In this multicentre trial, patients undergoing lung resection surgery were randomised to either a driving pressure group (n=650) receiving an alveolar recruitment/individualised PEEP to deliver the lowest driving pressure or to a conventional protective ventilation group (n=650) with fixed PEEP of 5 cm H2O. The primary outcome was a composite of pulmonary complications within 7 days postoperatively. RESULTS: The modified intention-to-treat analysis included 1170 patients (mean [standard deviation, sd]; age, 63 [10] yr; 47% female). The mean driving pressure was 7.1 cm H2O in the driving pressure group vs 9.2 cm H2O in the protective ventilation group (mean difference [95% confidence interval, CI]; -2.1 [-2.4 to -1.9] cm H2O; P<0.001). The incidence of pulmonary complications was not different between the two groups: driving pressure group (233/576, 40.5%) vs protective ventilation group (254/594, 42.8%) (risk difference -2.3%; 95% CI, -8.0% to 3.3%; P=0.42). Intraoperatively, lung compliance (mean [sd], 42.7 [12.4] vs 33.5 [11.1] ml cm H2O-1; P<0.001) and Pao2 (median [inter-quartile range], 21.5 [14.5 to 30.4] vs 19.5 [13.5 to 29.1] kPa; P=0.03) were higher and the need for rescue ventilation was less frequent (6.8% vs 10.8%; P=0.02) in the driving pressure group. CONCLUSIONS: In lung resection surgery, a driving pressure-guided ventilation improved pulmonary mechanics intraoperatively, but did not reduce the incidence of postoperative pulmonary complications compared with a conventional protective ventilation. CLINICAL TRIAL REGISTRATION: NCT04260451.


Subject(s)
Thoracic Surgery , Thoracic Surgical Procedures , Humans , Female , Middle Aged , Male , Positive-Pressure Respiration/adverse effects , Lung , Postoperative Complications/epidemiology , Postoperative Complications/prevention & control , Postoperative Complications/etiology , Thoracic Surgical Procedures/adverse effects , Tidal Volume
18.
Eur Spine J ; 32(8): 2875-2881, 2023 08.
Article in English | MEDLINE | ID: mdl-37029807

ABSTRACT

INTRODUCTION: Endoscopic techniques are becoming popular among spine surgeons because of their advantages. Though the advantages of endoscopic spine surgery are evident and patients can be discharged home within hours of surgery, readmissions can be sought for incomplete relief of leg pain, recurrent disc herniation, and recurrent leg pain. We aim to find out the factors related to the readmission of patients treated for lumbar pathologies. MATERIALS AND METHODS: This is a retrospective analysis of the data between the time duration of 2012 and 2022. Patients in the age group of 18-85 years, with lumbar disc herniation treated by transforaminal endoscopic lumbar procedures, were included. The patients who were readmitted within 90 days were included in the R Group and those who were not were included in the NR group. Univariable and multivariable logistic regression analyses were used to find the risk factors for 90-day readmission. RESULTS: There were a total of 1542 patients enrolled in this study. Sex, number of episodes before admission, hypertension, smoking, BMI, migration, disc height, disc height index, spondylolisthesis, instability, pelvic tilt (PT), and disc cross-sectional area (CSA) were found significant on univariable analysis. Age, spondylolisthesis, instability and muscle CSA were the only variables that were found to be statistically significant on multivariable analysis. CONCLUSIONS: This study shows that the elderly age group, presence of spondylolisthesis, segmental instability and decreased muscle cross-sectional area are independent risk factors for 90-day hospital readmissions. Patients having the above risk factors should be carefully counseled regarding the possibility of readmission in the future.


Subject(s)
Diskectomy , Intervertebral Disc Displacement , Lumbar Vertebrae , Patient Readmission , Republic of Korea/epidemiology , Risk Factors , Patient Readmission/statistics & numerical data , Lumbar Vertebrae/surgery , Humans , Male , Female , Adolescent , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Endoscopy/statistics & numerical data , Diskectomy/statistics & numerical data , Intervertebral Disc Displacement/epidemiology , Pain
19.
J Am Soc Nephrol ; 33(1): 186-200, 2022 01.
Article in English | MEDLINE | ID: mdl-34725107

ABSTRACT

BACKGROUND: Tertiary lymphoid tissues (TLTs) are ectopic lymphoid tissues found in chronically inflamed organs. Although studies have documented TLT formation in transplanted kidneys, the clinical relevance of these TLTs remains controversial. We examined the effects of TLTs on future graft function using our histologic TLT maturity stages and the association between TLTs and Banff pathologic scores. We also analyzed the risk factors for the development of TLTs. METHODS: Serial protocol biopsy samples (0 hour, 1, 6, and 12 months) without rejection were retrospectively analyzed from 214 patients who underwent living donor kidney transplantation. TLTs were defined as lymphocyte aggregates with signs of proliferation and their stages were determined by the absence (stage I) or presence (stage II) of follicular dendritic cells. RESULTS: Only 4% of patients exhibited TLTs at the 0-hour biopsy. Prevalence increased to almost 50% at the 1-month biopsy, and then slightly further for 12 months. The proportion of advanced stage II TLTs increased gradually, reaching 19% at the 12-month biopsy. Presence of stage II TLTs was associated with higher risk of renal function decline after transplantation compared with patients with no TLT or stage I TLTs. Stage II TLTs were associated with more severe tubulitis and interstitial fibrosis/tubular atrophy at 12 months and predicted poorer graft function independently from the degree of interstitial inflammation. Pretransplantation rituximab treatment dramatically attenuated the development of stage II TLTs. CONCLUSIONS: TLTs are commonly found in clinically stable transplanted kidneys. Advanced stage II TLTs are associated with progressive graft dysfunction, independent of interstitial inflammation.


Subject(s)
Choristoma/pathology , Kidney Diseases/pathology , Kidney Transplantation/adverse effects , Lymphoid Tissue , Primary Graft Dysfunction/etiology , Primary Graft Dysfunction/pathology , Adult , Aged , Biopsy , Female , Glomerular Filtration Rate , Humans , Kidney Diseases/surgery , Male , Middle Aged , Retrospective Studies
20.
Sensors (Basel) ; 23(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37447913

ABSTRACT

This study proposes a novel hybrid simulation technique for analyzing structural deformation and stress using light detection and ranging (LiDAR)-scanned point cloud data (PCD) and polynomial regression processing. The method estimates the edge and corner points of the deformed structure from the PCD. It transforms into a Dirichlet boundary condition for the numerical simulation using the particle difference method (PDM), which utilizes nodes only based on the strong formulation, and it is advantageous for handling essential boundaries and nodal rearrangement, including node generation and deletion between analysis steps. Unlike previous studies, which relied on digital images with attached targets, this research uses PCD acquired through LiDAR scanning during the loading process without any target. Essential boundary condition implementation naturally builds a boundary value problem for the PDM simulation. The developed hybrid simulation technique was validated through an elastic beam problem and a three-point bending test on a rubber beam. The results were compared with those of ANSYS analysis, showing that the technique accurately approximates the deformed edge shape leading to accurate stress calculations. The accuracy improved when using a linear strain model and increasing the number of PDM model nodes. Additionally, the error that occurred during PCD processing and edge point extraction was affected by the order of polynomial regression equation. The simulation technique offers advantages in cases where linking numerical analysis with digital images is challenging and when direct mechanical gauge measurement is difficult. In addition, it has potential applications in structural health monitoring and smart construction involving machine leading techniques.


Subject(s)
Cloud Computing , Psychotherapy , Computer Simulation , Linear Models , Records
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