Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 143
Filter
1.
Adv Sci (Weinh) ; : e2310197, 2024 Mar 17.
Article in English | MEDLINE | ID: mdl-38493313

ABSTRACT

Hexagonal boron nitride (h-BN) is a key ingredient for various 2D van der Waals heterostructure devices, but the exact role of h-BN encapsulation in relation to the internal defects of 2D semiconductors remains unclear. Here, it is reported that h-BN encapsulation greatly removes the defect-related gap states by stabilizing the chemisorbed oxygen molecules onto the defects of monolayer WS2 crystals. Electron energy loss spectroscopy (EELS) combined with theoretical analysis clearly confirms that the oxygen molecules are chemisorbed onto the defects of WS2 crystals and are fixated by h-BN encapsulation, with excluding a possibility of oxygen molecules trapped in bubbles or wrinkles formed at the interface between WS2 and h-BN. Optical spectroscopic studies show that h-BN encapsulation prevents the desorption of oxygen molecules over various excitation and ambient conditions, resulting in a greatly lowered and stabilized free electron density in monolayer WS2 crystals. This suppresses the exciton annihilation processes by two orders of magnitude compared to that of bare WS2 . Furthermore, the valley polarization becomes robust against the various excitation and ambient conditions in the h-BN encapsulated WS2 crystals.

2.
Chem Commun (Camb) ; 60(29): 3930-3933, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38497420

ABSTRACT

We describe a bottom-up synthesis of giant vesicles (GVs) utilizing an artificial stimuli-responsive diazobenzene lipid building block. Controlled by light, the GVs can exhibit dynamic behaviors, including reversible formation, the generation of highly multilamellar assemblies, and vesicle capturing and releasing events.

3.
Sci Rep ; 14(1): 5258, 2024 03 04.
Article in English | MEDLINE | ID: mdl-38438522

ABSTRACT

Vertebral artery dissection (VAD) is often associated with medullary infarction; however, an underlying cause may be underestimated. This study aimed to assess the diagnostic potential of hypointense signal lesions along the arterial pathways using susceptibility-weighted imaging (SWI) as a feasible indicator of VAD in medullary infarction. A retrospective analysis was conducted using clinical data, brain magnetic resonance imaging, and angiography records of 79 patients diagnosed with medullary infarction between January 2014 and December 2021. Patients were categorized into an angiography-confirmed dissection group and a non-dissection group based on imaging findings. A new possible dissection group was identified using SWI, including cases with hypointense signals along the arteries without calcification or cardioembolism. We compared the clinical characteristics of the two groups before and after the addition of the hypointense signal as a marker of VAD. The angiography-confirmed dissection group included 12 patients (15%). Among patients lacking angiographic VAD evidence, 14 subjects displayed hypointense signals on SWI: nine patients along the vertebral artery and five subjects at the posterior inferior cerebellar artery without calcification or cardioembolism. The newly classified dissection group was younger, had a lower prevalence of diabetes mellitus and stroke history, and revealed increased headaches compared to the non-dissection group. Hypointense signal detection on SWI in medullary infarctions shows promise as a diagnostic indicator for VAD. Suspicion of VAD is needed when the hypointense signal on SWI is noted, and considering different treatment strategies with angiographic follow-up will be helpful.


Subject(s)
Calcinosis , Vertebral Artery Dissection , Humans , Vertebral Artery Dissection/diagnostic imaging , Retrospective Studies , Vertebral Artery , Magnetic Resonance Imaging , Infarction
4.
Acta Neurochir (Wien) ; 166(1): 42, 2024 Jan 27.
Article in English | MEDLINE | ID: mdl-38280083

ABSTRACT

OBJECTIVE: The effectiveness of revascularization for complex aneurysms is well-established. This study aimed to describe the technical characteristics and clinical efficacy of intracranial-to-intracranial (IC-IC) bypass for the treatment of complex intracranial aneurysms. METHODS: We retrospectively reviewed all patients with aneurysms who underwent a preplanned combination of surgical or endovascular treatment and IC-IC bypass at our institution between January 2006 and September 2023. IC-IC bypass techniques included four strategies: type A (end-to-end reanastomosis), type B (end-to-side reimplantation), type C (in situ side-to-side anastomosis), and type D (IC-IC bypass with a graft vessel). RESULTS: During the study period, ten patients with aneurysms each underwent IC-IC bypass surgery. Aneurysms were located in the middle cerebral artery (60.0%), anterior temporal artery (10.0%), anterior cerebral artery (20.0%), and vertebral artery (10.0%). There were three saccular aneurysms (30.0%), two fusiform aneurysms (20.0%), one dissecting aneurysm (10.0%), and four pseudoaneurysms (40.0%). We performed the type A strategy on five patients (50.0%), type B on one (10.0%), type C on one (10.0%), and type D on three (30.0%). During a mean period of 68.3 months, good clinical outcomes (modified Rankin Scale score, 0-2) were observed in all patients. Follow-up angiography demonstrated complete aneurysmal obliteration in all patients and good bypass patency in nine of ten patients (90.0%). CONCLUSION: The treatment of complex aneurysms remains a challenge with conventional surgical or endovascular treatments. IC-IC bypass surgery is a useful technique, associated with favorable clinical outcomes, for treating complex aneurysms.


Subject(s)
Cerebral Revascularization , Intracranial Aneurysm , Humans , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Cerebral Revascularization/methods , Retrospective Studies , Treatment Outcome , Middle Cerebral Artery/surgery
5.
Small ; 20(9): e2304747, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37847909

ABSTRACT

All-solid-state lithium batteries (ASSLBs) are considered promising alternatives to current lithium-ion batteries that employ liquid electrolytes due to their high energy density and enhanced safety. Among various types of solid electrolytes, sulfide-based electrolytes are being actively studied, because they exhibit high ionic conductivity and high ductility, which enable good interfacial contacts in solid electrolytes without sintering at high temperatures. To improve the energy density of the sulfide-based ASSLBs, it is essential to increase the loading of active material in the composite cathode. In this study, the Ni-rich LiNix Coy Mn1-x-y O2 (NCM) materials are explored with different Ni content, particle size, and crystalline form to probe suitable cathode active materials for high-performance ASSLBs with high energy density. The results reveal that single-crystalline LiNi0.82 Co0.10 Mn0.08 O2 material with a small particle size exhibits the best cycling performance in the ASSLB assembled with a high mass loaded cathode (active mass loading: 26 mg cm-2 , areal capacity: 5.0 mAh cm-2 ) in terms of discharge capacity, capacity retention, and rate capability.

6.
J Am Chem Soc ; 145(47): 25815-25823, 2023 11 29.
Article in English | MEDLINE | ID: mdl-37963186

ABSTRACT

Living systems create remarkable complexity from a limited repertoire of biological building blocks by controlling assembly dynamics at the molecular, cellular, and multicellular level. An open question is whether simplified synthetic cells can gain similar complex functionality by being driven away from equilibrium. Here, we describe a dynamic synthetic cell system assembled using artificial lipids that are responsive to both light and chemical stimuli. Irradiation of disordered aggregates of lipids leads to the spontaneous emergence of giant cell-like vesicles, which revert to aggregates when illumination is turned off. Under irradiation, the synthetic cell membranes can interact with chemical building blocks, remodeling their composition and forming new structures that prevent the membranes from undergoing retrograde aggregation processes. The remodeled light-responsive synthetic cells reversibly alter their shape under irradiation, transitioning from spheres to rodlike shapes, mimicking energy-dependent functions normally restricted to living materials. In the presence of noncovalently interacting multivalent polymers, light-driven shape changes can be used to trigger vesicle cross-linking, leading to the formation of functional synthetic tissues. By controlling light and chemical inputs, the stepwise, one-pot transformation of lipid aggregates to multivesicular synthetic tissues is feasible. Our results suggest a rationale for why even early protocells may have required and evolved simple mechanisms to harness environmental energy sources to coordinate hierarchical assembly processes.


Subject(s)
Artificial Cells , Cell Membrane , Lipids
7.
Cancers (Basel) ; 15(12)2023 Jun 17.
Article in English | MEDLINE | ID: mdl-37370835

ABSTRACT

An in vitro culture period of at least 2 weeks is required to produce sufficient natural killer (NK) cells for immunotherapy, which are the key effectors in hematological malignancy treatment. Mitochondrial damage and fragmentation reduce the NK cell immune surveillance capacity. Thus, we hypothesized that the transfer of healthy mitochondria to NK cells could enhance their anticancer effects. Allogeneic healthy mitochondria isolated from WRL-68 cells were transferred to NK cells. We evaluated NK cells' proliferative capacity, cell cycle, and cytotoxic capacity against various cancer cell types by analyzing specific lysis and the cytotoxic granules released. The relationship between the transferred allogenic mitochondrial residues and NK cell function was determined. After mitochondrial transfer, the NK cell proliferation rate was 1.2-fold higher than that of control cells. The mitochondria-treated NK cells secreted a 2.7-, 4.1-, and 5-fold higher amount of granzyme B, perforin, and IFN-γ, respectively, when co-cultured with K562 cells. The specific lysis of various solid cancer cells increased 1.3-1.6-fold. However, once allogeneic mitochondria were eliminated, the NK cell activity returned to the pre-mitochondrial transfer level. Mitochondria-enriched NK cells have the potential to be used as a novel solid cancer treatment agent, without the need for in vitro cytokine-induced culture.

8.
Brain Sci ; 13(5)2023 May 10.
Article in English | MEDLINE | ID: mdl-37239252

ABSTRACT

Treatments to restore the balance of the temporomandibular joint (TMJ) are performed in the field of complementary and alternative medicine; however, evidence supporting this approach remains weak. Therefore, this study attempted to establish such evidence. Bilateral common carotid artery stenosis (BCAS) operation, which is commonly used for the establishment of a mouse model of vascular dementia, was performed, followed by tooth cutting (TEX) for maxillary malocclusion to promote the imbalance of the TMJ. Behavioural changes, changes in nerve cells and changes in gene expression were assessed in these mice. The TEX-induced imbalance of the TMJ caused a more severe cognitive deficit in mice with BCAS, as indicated by behavioural changes in the Y-maze test and novel object recognition test. Moreover, inflammatory responses were induced via astrocyte activation in the hippocampal region of the brain, and the proteins involved in inflammatory responses were found to be involved in these changes. These results indirectly show that therapies that restore the balance of the TMJ can be effectively used for the management of cognitive-deficit-related brain diseases associated with inflammation.

9.
Sensors (Basel) ; 23(6)2023 Mar 22.
Article in English | MEDLINE | ID: mdl-36992066

ABSTRACT

Lightning strikes can cause significant damage to critical infrastructure and pose a serious threat to public safety. To ensure the safety of facilities and investigate the causes of lightning accidents, we propose a cost-effective design method for a lightning current measuring instrument that uses a Rogowski coil and dual signal conditioning circuits to detect a wide range of lightning currents, ranging from hundreds of A to hundreds of kA. To implement the proposed lightning current measuring instrument, we design signal conditioning circuits and software capable of detecting and analyzing lightning currents from ±500 A to ±100 kA. By employing dual signal conditioning circuits, it offers the advantage of detecting a wide range of lightning currents compared to existing lightning current measuring instruments. The proposed instrument has the following features: First, the peak current, polarity, T1 (front time), T2 (time to half value), and Q (amount of energy of the lightning current) can be analyzed and measured with a fast sampling time of 380 ns. Second, it can distinguish whether a lightning current is induced or direct. Third, a built-in SD card is provided to save the detected lightning data. Finally, it provides Ethernet communication capability for remote monitoring. The performance of the proposed instrument is evaluated and validated by applying induced and direct lightning using a lightning current generator.

10.
Int J Mol Sci ; 23(24)2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36555546

ABSTRACT

In this study, we propose the use of artificial synaptic transistors with coplanar-gate structures fabricated on paper substrates comprising biocompatible and low-cost potato-starch electrolyte and indium-gallium-zinc oxide (IGZO) channels. The electrical double layer (EDL) gating effect of potato-starch electrolytes enabled the emulation of biological synaptic plasticity. Frequency dependence measurements of capacitance using a metal-insulator-metal capacitor configuration showed a 1.27 µF/cm2 at a frequency of 10 Hz. Therefore, strong capacitive coupling was confirmed within the potato-starch electrolyte/IGZO channel interface owing to EDL formation because of internal proton migration. An electrical characteristics evaluation of the potato-starch EDL transistors through transfer and output curve resulted in counterclockwise hysteresis caused by proton migration in the electrolyte; the hysteresis window linearly increased with maximum gate voltage. A synaptic functionality evaluation with single-spike excitatory post-synaptic current (EPSC), paired-pulse facilitation (PPF), and multi-spike EPSC resulted in mimicking short-term synaptic plasticity and signal transmission in the biological neural network. Further, channel conductance modulation by repetitive presynaptic stimuli, comprising potentiation and depression pulses, enabled stable modulation of synaptic weights, thereby validating the long-term plasticity. Finally, recognition simulations on the Modified National Institute of Standards and Technology (MNIST) handwritten digit database yielded a 92% recognition rate, thereby demonstrating the applicability of the proposed synaptic device to the neuromorphic system.


Subject(s)
Solanum tuberosum , Zinc Oxide , Protons , Transistors, Electronic , Zinc Oxide/chemistry , Electrolytes/chemistry
11.
Sci Rep ; 12(1): 22041, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36543825

ABSTRACT

Low-intensity ultrasound (LIUS) enhances the proliferation rate of various mammalian stem cells through mechanical stimulation. This study quantitively finds suitable LIUS stimulation parameters for increasing the proliferation rate of human adipose-derived mesenchymal stem cells (hAdMSCs) for mass production. Various stimulation conditions of LIUS were assessed based on the beam pattern of the ultrasonic transducer and the attenuation of the sound waves. Using optimal LIUS stimulation parameters for enhancing proliferation of hAdMSCs taken from bromodeoxyuridine (BrdU) incorporation assay, long-term culture of hAdMSCs was performed for 16 days. The resultant hAdMSCs were characterized for various biomarkers such as CD34-, CD45-, CD73+, CD95+, CD105+ and cytological staining and a cytokine array assay. LIUS stimulation parameters found for enhancing the hAdMSCs proliferation were the frequency of 5 MHz, an intensity of 300 mWcm-2, a duration of 10 min per day, and continuous waves with a 100% duty cycle. The LIUS stimulated hAdMSCs group showed a 3.25-fold increase in the cell number compared to the control group after 16 days of culture. By confirming the effects of quantitatively measured LIUS stimulation on the enhancement of hAdMSCs proliferation, this study may be a foundation for the applications of LIUS stimulation in the industrial-scale production of hAdMSCs.


Subject(s)
Mesenchymal Stem Cells , Animals , Humans , Cells, Cultured , Stem Cells , Ultrasonography , Ultrasonics , Mammals
12.
Taehan Yongsang Uihakhoe Chi ; 83(1): 112-126, 2022 Jan.
Article in Korean | MEDLINE | ID: mdl-36237350

ABSTRACT

Purpose: To determine the value of 3 Tesla (T) MRI texture analysis for predicting tumor margin infiltration in soft tissue sarcomas. Materials and Methods: Thirty-one patients who underwent 3T MRI and had a pathologically confirmed diagnosis of soft tissue sarcoma were included in this study. Margin infiltration on pathology was used as the gold standard. Texture analysis of soft tissue sarcomas was performed on axial T1-weighted images (WI) and T2WI, fat-suppressed contrast-enhanced (CE) T1WI, diffusion-weighted images (DWI) with b-value of 800 s/mm2, and apparent diffusion coefficient (ADC) was mapped. Quantitative parameters were compared between sarcomas with infiltrative margins and those with circumscribed margins. Results: Among the 31 patients with soft tissue sarcomas, 23 showed tumor margin infiltration on pathology. There were significant differences in kurtosis with the spatial scaling factor (SSF) of 0 and 6 on T1WI, kurtosis (SSF, 0) on CE-T1WI, skewness (SSF, 0) on DWI, and skewness (SSF, 2, 4) on ADC between sarcomas with infiltrative margins and those with circumscribed margins (p ≤ 0.046). The area under the receiver operating characteristic curve based on MR texture features for identification of infiltrative tumor margins was 0.951 (p < 0.001). Conclusion: MR texture analysis is reliable and accurate for the prediction of infiltrative margins of soft tissue sarcomas.

13.
Materials (Basel) ; 15(20)2022 Oct 19.
Article in English | MEDLINE | ID: mdl-36295378

ABSTRACT

Chemical warfare agents (CWAs) have been threatening human civilization and its existence because of their rapid response, toxic, and irreversible nature. The hybrid nanostructured composites were synthesized by the hydrothermal process to detect the dimethyl methyl phosphonate (DMMP), a simulant of G-series nerve agents, especially sarin. Cellulose (CE), manganese oxide cellulose (MnO2@CE), and MnO2@CE/polypyrrole (PPy) exhibited a frequency shift of 0.4, 4.8, and 8.9 Hz, respectively, for a DMMP concentration of 25 ppm in the quartz crystal microbalance (QCM). In surface acoustic wave (SAW) sensor, they exhibited 187 Hz, 276 Hz, and 78 Hz, respectively. A comparison between CE, MnO2@CE, and MnO2@CE/PPy demonstrated that MnO2@CE/PPy possesses excellent linearity with a coefficient of determination (COD or R2) of 0.992 and 0.9547 in the QCM and SAW sensor. The hybrid composite materials showed a reversible adsorption and desorption phenomenon in the reproducibility test. The response and recovery times indicated that MnO2@CE/PPy showed the shortest response (~23 s) and recovery times (~42 s) in the case of the QCM sensor. Hence, the pristine CE and its nanostructured composites were compared to analyze the sensing performance based on sensitivity, selectivity, linearity, reproducibility, and response and recovery times to detect the simulant of nerve agents.

14.
Molecules ; 27(19)2022 Oct 02.
Article in English | MEDLINE | ID: mdl-36235052

ABSTRACT

Target protein degradation has emerged as a promising strategy for the discovery of novel therapeutics during the last decade. Proteolysis-targeting chimera (PROTAC) harnesses a cellular ubiquitin-dependent proteolysis system for the efficient degradation of a protein of interest. PROTAC consists of a target protein ligand and an E3 ligase ligand so that it enables the target protein degradation owing to the induced proximity with ubiquitin ligases. Although a great number of PROTACs has been developed so far using previously reported ligands of proteins for their degradation, E3 ligase ligands have been mostly limited to either CRBN or VHL ligands. Those PROTACs showed their limitation due to the cell type specific expression of E3 ligases and recently reported resistance toward PROTACs with CRBN ligands or VHL ligands. To overcome these hurdles, the discovery of various E3 ligase ligands has been spotlighted to improve the current PROTAC technology. This review focuses on currently reported E3 ligase ligands and their application in the development of PROTACs.


Subject(s)
Ubiquitin-Protein Ligases , Ubiquitin , Ligands , Proteins/metabolism , Proteolysis , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/metabolism
15.
Nanomaterials (Basel) ; 12(17)2022 Aug 27.
Article in English | MEDLINE | ID: mdl-36080003

ABSTRACT

Chemical warfare agents (CWAs) have inflicted monumental damage to human lives from World War I to modern warfare in the form of armed conflict, terrorist attacks, and civil wars. Is it possible to detect the CWAs early and prevent the loss of human lives? To answer this research question, we synthesized hybrid composite materials to sense CWAs using hydrothermal and thermal reduction processes. The synthesized hybrid composite materials were evaluated with quartz crystal microbalance (QCM) and surface acoustic wave (SAW) sensors as detectors. The main findings from this study are: (1) For a low dimethyl methyl phosphonate (DMMP) concentration of 25 ppm, manganese dioxide nitrogen-doped graphene oxide (NGO@MnO2) and NGO@MnO2/Polypyrrole (PPy) showed the sensitivities of 7 and 51 Hz for the QCM sensor and 146 and 98 Hz for the SAW sensor. (2) NGO@MnO2 and NGO@MnO2/PPy showed sensitivities of more than 50-fold in the QCM sensor and 100-fold in the SAW sensor between DMMP and potential interferences. (3) NGO@MnO2 and NGO@MnO2/PPy showed coefficients of determination (R2) of 0.992 and 0.975 for the QCM sensor and 0.979 and 0.989 for the SAW sensor. (4) NGO@MnO2 and NGO@MnO2/PPy showed repeatability of 7.00 ± 0.55 and 47.29 ± 2.69 Hz in the QCM sensor and 656.37 ± 73.96 and 665.83 ± 77.50 Hz in the SAW sensor. Based on these unique findings, we propose NGO@MnO2 and NGO@MnO2/PPy as potential candidate materials that could be used to detect CWAs.

16.
Head Neck ; 44(12): 2796-2802, 2022 12.
Article in English | MEDLINE | ID: mdl-36129318

ABSTRACT

BACKGROUND: This study aimed to evaluate the incidence and risk factors of occult metastasis to superficial level VI, defined as the space anterior to the strap muscles, including the lymph nodes between the sternocleidomastoid and sternohyoid muscles and suprasternal space lymph nodes. METHODS: We studied 129 patients with papillary thyroid carcinoma who underwent thyroidectomy and neck dissection, including superficial level VI dissection. RESULTS: Of the 129 patients, 62 (48%) had lymph nodes in the harvested specimens of superficial level VI, and the mean number of lymph nodes retrieved was 1.9 ± 1.2. Occult metastasis to superficial level VI occurred in four patients (3.1%). No significant risk factors of superficial level VI occult metastasis were noted in multivariate analysis. CONCLUSIONS: Occult metastasis to superficial level VI was rare in patients with papillary thyroid carcinoma. Therefore, prophylactic dissection of superficial level VI may not be necessary for primary papillary thyroid carcinoma.


Subject(s)
Carcinoma, Papillary , Thyroid Neoplasms , Humans , Thyroid Cancer, Papillary/pathology , Carcinoma, Papillary/pathology , Thyroid Neoplasms/surgery , Thyroid Neoplasms/pathology , Lymphatic Metastasis/pathology , Neck Dissection , Lymph Nodes/pathology , Thyroidectomy , Retrospective Studies
17.
Phys Act Nutr ; 26(2): 28-35, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35982627

ABSTRACT

PURPOSE: To determine the correlations of differences in the income level with the presence of metabolic syndrome (MetS), energy intake, and physical activity across Korean elderly populations. METHODS: We obtained data from 2,139 elderly individuals (aged >65 years) based on the Korea National Health and Nutrition Examination Survey (KNHANES) (2016‒2018). We analyzed the levels of physical activity (PA) and energy intake using the survey data. Moreover, we analyzed the differences in energy intake and PA levels according to the income level and MetS. RESULTS: Compared with the non-MetS group, the MetS group displayed significantly higher levels of waist circumference (p=0.000), triglycerides (p=0.000), systolic blood pressure (p=0.000), diastolic blood pressure (p=0.016), and fasting blood glucose (p=0.000) for both high and low income levels. However, the level of high-density lipoprotein cholesterol was significantly lower in the MetS group than that in the non-MetS group (p=0.000). The level of smoking in non-MetS men was significantly higher than that in MetS men across all participants (p=0.047). Except carbohydrate intake, the total energy intake (p=0.022), fat intake (p=0.009), and protein intake (p=0.005) were significantly lower in the MetS group than those in the non-MetS group for high income levels. We obtained similar results for low income levels. The two-way analysis of variance (ANOVA) did not identify an interaction between the income level and the presence of MetS; however, the total energy, i.e., the level of total energy intake, was significantly lower in participants with low income levels than in those with high income levels. For high income levels, transport PA (p=0.002), vigorous recreational PA (p=0.001), moderate recreational PA (p=0.001), and total PA (p=0.000) were significantly lower in the MetS group than those in the non-MetS group. For low income levels, moderate occupational PA (p=0.012), transport PA (p=0.018), and total PA ((p=0.000) were significantly lower in the MetS group than those in the non-MetS group. The total PA, i.e., the level of energy consumption, was significantly lower in the elderly with low income levels than in those with high income levels. CONCLUSION: Regardless of the income level, the elderly with MetS exhibited low levels of energy intake and PA, compared with those without MetS. In addition, regardless of the presence of MetS, the elderly with low income levels exhibited lesser energy intake and PA. These findings implied the need for balanced nutrient intake and increased participation in PA as well as education and program development to prevent MetS in the elderly.

18.
Int J Mol Sci ; 23(9)2022 Apr 30.
Article in English | MEDLINE | ID: mdl-35563402

ABSTRACT

Renal fibrosis is an irreversible and progressive process that causes severe dysfunction in chronic kidney disease (CKD). The progression of CKD stages is highly associated with a gradual reduction in serum Klotho levels. We focused on Klotho protein as a key therapeutic factor against CKD. Urine-derived stem cells (UDSCs) have been identified as a novel stem cell source for kidney regeneration and CKD treatment because of their kidney tissue-specific origin. However, the relationship between UDSCs and Klotho in the kidneys is not yet known. In this study, we discovered that UDSCs were stem cells that expressed Klotho protein more strongly than other mesenchymal stem cells (MSCs). UDSCs also suppressed fibrosis by inhibiting transforming growth factor (TGF)-ß in HK-2 human renal proximal tubule cells in an in vitro model. Klotho siRNA silencing reduced the TGF-inhibiting ability of UDSCs. Here, we suggest an alternative cell source that can overcome the limitations of MSCs through the synergetic effect of the origin specificity of UDSCs and the anti-fibrotic effect of Klotho.


Subject(s)
Kidney , Klotho Proteins , Renal Insufficiency, Chronic , Stem Cells , Female , Fibrosis , Glucuronidase/metabolism , Humans , Kidney/metabolism , Kidney/pathology , Male , Regeneration , Renal Insufficiency, Chronic/metabolism , Signal Transduction , Stem Cells/metabolism , Transforming Growth Factor beta/metabolism , Transforming Growth Factor beta1/metabolism , Urine
19.
J Am Board Fam Med ; 35(2): 370-379, 2022.
Article in English | MEDLINE | ID: mdl-35379723

ABSTRACT

INTRODUCTION: This study examines the evolution of student and physician interest in primary care from medical school matriculation to practice, focusing on student factors that potentiate primary care (PC) practice. METHODS: We compiled a dataset of 2,047 Michigan State University College of Human Medicine graduates from 1991 to 2010. PC interest was assessed using the Association of American Medical Colleges (AAMC) matriculating student (MSQ) and graduation (GQ) questionnaires. PC practice was determined using AMA physician Masterfile data. C2 analyses and logistic regression were used to examine factors that predict PC practice. RESULTS: PC interest at matriculation and at graduation were the factors most likely to predict PC practice. After controlling for URM status, gender, and rural origin, the odds of practicing PC among those with a sustained interest in PC (on both the MSQ and GQ) were 100 times higher than those with no interest in PC, on either survey (P < .01). Among those students who developed an interest in PC by graduation, the odds of practicing PC were 60 times higher than noninterested students (P < .01). Finally, among students who were interested in PC at matriculation, but not graduation, the odds of eventually practicing PC were 3.8 times higher than noninterested students (P < .01). CONCLUSIONS: Our study suggests that cultivating PC interest at any point during medical school may predict PC practice. Early and sustained interest in primary care was the most substantial predictor of PC practice in our study, highlighting the need for primary care education even before medical school matriculation.


Subject(s)
Students, Medical , Career Choice , Humans , Michigan , Primary Health Care , Universities
20.
Chemistry ; 28(30): e202200533, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35302689

ABSTRACT

The photophysical behaviors of fluorescent molecules largely determine their major utility in biological studies. Despite their well-defined characteristics, classical fluorophores have often been challenged by their limited synthetic methodology and tunability in adjusting intrinsic optical properties. A novel heterocyclic core equipped with modular functional groups could offer the flexibility to control its photophysical properties with a minimum synthetic effort. By conducting a systematic analysis guided by quantum calculations, we proposed the furoindolizine-based molecular framework as a unique fluorescent platform capable of providing versatile photophysical properties with minimal structural modification. A broad tunability of furoindolizine derivatives' photophysical properties such as emission wavelength, Stokes shift, fluorescent brightness, and charge transfer characteristics was achieved through synergistic interaction between two functional moieties. Furthermore, this modular platform led to live-cell imaging probes with two distinct optical features simply by reorganizing a pair of functional moieties.


Subject(s)
Fluorescent Dyes , Fluorescent Dyes/chemistry , Ionophores
SELECTION OF CITATIONS
SEARCH DETAIL
...