RESUMO
We aimed to conduct a proof-of-concept study of INV-001 in visualizing lymphatic vessels and nodes without venous contamination and to determine the optimal dose condition of INV-001 for magnetic resonance lymphangiography (MRL) in healthy beagles. MRL was performed using a 3.0-Tesla (T) whole body clinical magnetic resonance imaging (MRI) scanner. A dose-finding study of INV-001 for MRL in beagles (N = 6) was carried out according to an adaptive optimal dose finding design. For the reproducibility study (N = 6), MRL was conducted at selected INV-001 doses (0.056 and 0.112 mg Fe/kg) with a 15 mM concentration. Additionally, an excretion study (N = 3) of INV-001 was conducted by analyzing T1, T2, and T2* maps of the liver and kidney 48 h post-administration. INV-001 administration at doses of 0.056 and 0.112 mg Fe/kg (concentration: 15 mM) consistently demonstrated the visualization of contrast-enhanced lymphatic vessels and nodes without venous contamination in the beagles. The contrast enhancement effect was highest at 30 min after INV-001 administration, then gradually decreasing. No toxicity-related issues were identified during the study. After 48 h, the T1, T2, and T2* values in the liver and both kidneys were found to be comparable to the pre-administration values, indicating thorough INV-001 excretion. The optimal dosing conditions of INV-001 for MRL for contrast-enhanced visualization of lymphatic vessels and nodes exclusively with no venous contamination in beagles was determined to be 0.056 mg Fe/kg with a 15 mM concentration.
Assuntos
Meios de Contraste , Vasos Linfáticos , Linfografia , Imageamento por Ressonância Magnética , Animais , Cães , Imageamento por Ressonância Magnética/métodos , Linfografia/métodos , Meios de Contraste/administração & dosagem , Vasos Linfáticos/diagnóstico por imagem , Masculino , Reprodutibilidade dos Testes , Feminino , Linfonodos/diagnóstico por imagem , Estudo de Prova de ConceitoRESUMO
PURPOSE: Gadolinium (Gd)-based contrast agents are primarily used for contrast-enhanced magnetic resonance lymphangiography (MRL). However, overcoming venous contamination issues remains challenging. This study aims to assess the MRL efficacy of the newly developed iron-based contrast agent (INV-001) that is specially designed to mitigate venous contamination issues. The study further explores the optimal dosage, including both injection volume and concentration, required to achieve successful visualization of the popliteal lymph nodes and surrounding lymphatic vessels. PROCEDURES: All animals utilized in this study were male Sprague-Dawley (SD) rats weighing between 250 and 300 g. The contrast agents prepared were injected intradermally in the fourth phalanx of both hind limbs using a 30-gauge syringe in SD rats. MRL was performed every 16 min on a coronal 3D time-of-flight sequence with saturation bands using a 9.4-T animal machine. RESULTS: Contrary to Gd-DOTA, which exhibited venous contamination in most animals irrespective of injection dosages and conditions, INV-001 showed no venous contamination. For Gd-DOTA, the popliteal lymph nodes and lymphatic vessels reached peak enhancement 16 min after injection from the injection site and then rapidly washed out. However, with INV-001, they reached peak enhancement between 16 and 32 min after injection, with prolonged visualization of the popliteal lymph node and lymphatic vessels. INV-001 at 0.45 µmol (15 mM, 30 µL) and 0.75 µmol (15 mM, 50 µL) achieved high scores for qualitative image analysis, providing good visualization of the popliteal lymph nodes and lymphatic vessels without issues of venous contamination, interstitial space enhancement, or lymph node enlargement. CONCLUSION: In MRL, INV-001, a novel T1 contrast agent based on iron, enables prolonged enhancement of popliteal lymph nodes and lymphatic vessels without venous contamination.
Assuntos
Meios de Contraste , Compostos Férricos , Gadolínio , Vasos Linfáticos , Linfografia , Imageamento por Ressonância Magnética , Ratos Sprague-Dawley , Animais , Meios de Contraste/química , Meios de Contraste/farmacocinética , Imageamento por Ressonância Magnética/métodos , Masculino , Linfografia/métodos , Gadolínio/química , Gadolínio/farmacocinética , Compostos Férricos/química , Compostos Férricos/farmacocinética , Vasos Linfáticos/diagnóstico por imagem , Ratos , Linfonodos/diagnóstico por imagem , Linfonodos/metabolismoRESUMO
Although magnetic nanoparticles demonstrate significant potential as magnetic resonance imaging (MRI) contrast agents, their negative contrasts, liver accumulation, and limited excretion hinder their application. Herein, we developed ultrasmall Mn-doped iron oxide nanoparticles (UMIOs) with distinct advantages as T1 MRI contrast agents. Exceptionally small particle sizes (ca. 2 nm) and magnetization values (5 emu gMn+Fe-1) of UMIOs provided optimal T1 contrast effects with an ideally low r2/r1 value of â¼1. Furthermore, the use of Mn as a dopant facilitated hepatocyte uptake of the particles, allowing liver imaging. In animal studies, UMIOs exhibited significantly enhanced contrasts for sequential T1 imaging of blood vessels and the liver, distinguishing them from conventional magnetic nanoparticles. UMIOs were systematically cleared via dual hepatobiliary and renal excretion pathways, highlighting their safety profile. These characteristics imply substantial potential of UMIOs as T1 contrast agents for the accurate diagnosis of liver diseases.
RESUMO
This study presents a methodology to prevent the overdesign of electric dispensers for dental impression materials by analyzing the necessary load and determining the appropriate pressurization speed and drive motor capacity. We derived an equation to calculate the required torque and rotational speed of the motor based on the extrusion load and the speed of the impression material. A specialized load measurement system was developed to measure the load necessary to extrude the impression material. Through experiments and image processing, we measured the radius of curvature of the trajectory of the impression material and correlated it with the pressurization speed. Techniques such as position coordinate plotting, curve fitting, and circle fitting were employed to determine the pressurization speed that aligns with the manufacturer's recommended curvature radius. These findings led to a substantial decrease in the necessary motor torque and rotational speed compared with the current standards. This research provides a systematic approach to sizing drive motors using extrusion load and pressurization speed, aiming to reduce overdesign, power consumption, and the weight and size of the motor and battery, thereby contributing to the development of more efficient and compact dental impression material dispensers.
RESUMO
Hematopoietic stem cell transplantation requires the collection of hematopoietic cells from patients or stem cell donors. Granulocyte colony-stimulating factor (G-CSF) is widely used in the clinic to mobilize hematopoietic stem and progenitor cells (HSPCs) from the adult bone marrow niche into circulation, allowing a collection of HSPCs from the blood. The mechanism by which G-CSF acts to mobilize HSPCs is unclear, with some studies showing a direct stimulation of stem cells and others suggesting that myeloid cells are required. In this study, we developed a heat-inducible G-CSF transgenic zebrafish line to study HSPC mobilization in vivo. Live imaging of HSPCs after G-CSF induction revealed an increase in circulating HSPCs, demonstrating a successful HSPC mobilization. These mobilized HSPCs went on to prematurely colonize the kidney marrow, the adult zebrafish hematopoietic niche. We eliminated neutrophils or macrophages using a nitroreductase-based cell ablation system and found that G-CSF still mobilizes HSPCs from the niche. Our findings indicate that neutrophils and macrophages are not required for G-CSF-induced HSPC mobilization from the embryonic hematopoietic niche.
Assuntos
Fator Estimulador de Colônias de Granulócitos , Transplante de Células-Tronco Hematopoéticas , Animais , Humanos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas/métodos , Peixe-Zebra/metabolismo , Neutrófilos/metabolismo , Macrófagos/metabolismoRESUMO
This study examines the impacts of copper and boron in parts per million (ppm) on the microstructure and mechanical properties of spheroidal graphite cast iron (SCI). Boron's inclusion increases the ferrite content whereas copper augments the stability of pearlite. The interaction between the two significantly influences the ferrite content. Differential scanning calorimetry (DSC) analysis indicates that boron alters the enthalpy change of the α + Fe3C â γ conversion and the α â γ conversion. Scanning electron microscope (SEM) analysis confirms the locations of copper and boron. Mechanical property assessments using a universal testing machine show that the inclusion of boron and copper decreases the tensile strength and yield strength of SCI, but simultaneously enhances elongation. Additionally, in SCI production, the utilization of copper-bearing scrap and trace amounts of boron-containing scrap metal, especially in the casting of ferritic nodular cast iron, offers potential for resource recycling. This highlights the importance of resource conservation and recycling in advancing sustainable manufacturing practices. These findings provide critical insights into the effects of boron and copper on SCI's behavior, contributing to the design and development of high-performance SCI materials.
RESUMO
In this study, the characteristics of the SKD61 material used for the stem of an extruder were analyzed through structural analysis, tensile testing, and fatigue testing. The extruder works by pushing a cylindrical billet into a die with a stem to reduce its cross-sectional area and increase its length, and it is currently used to extrude complex and diverse shapes of products in the field of plastic deformation processes. Finite element analysis was used to determine the maximum stress on the stem, which was found to be 1152 MPa, lower than the yield strength of 1325 MPa obtained from tensile testing. Fatigue testing was conducted using the stress-life (S-N) method, considering the characteristics of the stem, and statistical fatigue testing was employed to create an S-N curve. The predicted minimum fatigue life of the stem at room temperature was 424,998 cycles at the location with the highest stress, and the fatigue life decreased with increasing temperature. Overall, this study provides useful information for predicting the fatigue life of extruder stems and improving their durability.
RESUMO
The hematopoietic niche is a supportive microenvironment composed of distinct cell types, including specialized vascular endothelial cells that directly interact with hematopoietic stem and progenitor cells (HSPCs). The molecular factors that specify niche endothelial cells and orchestrate HSPC homeostasis remain largely unknown. Using multi-dimensional gene expression and chromatin accessibility analyses in zebrafish, we define a conserved gene expression signature and cis-regulatory landscape that are unique to sinusoidal endothelial cells in the HSPC niche. Using enhancer mutagenesis and transcription factor overexpression, we elucidate a transcriptional code that involves members of the Ets, Sox, and nuclear hormone receptor families and is sufficient to induce ectopic niche endothelial cells that associate with mesenchymal stromal cells and support the recruitment, maintenance, and division of HSPCs in vivo. These studies set forth an approach for generating synthetic HSPC niches, in vitro or in vivo, and for effective therapies to modulate the endogenous niche.
Assuntos
Nicho de Células-Tronco , Fatores de Transcrição , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células Endoteliais/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Regulação da Expressão GênicaRESUMO
The mitochondrial genome (mitogenome) of Aleochara (Aleochara) curtula (Goeze, 1777) (Coleoptera: Staphylinidae) is reported. This mitogenome (GenBank accession no. OL675411) is 16,600 bp in size and consists of 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), and two ribosomal RNA genes (rRNA). Most PCGs use typical mitochondrial stop codon (TAR) except for cox3, which uses a single T residue. The A, G, T, and C nucleotide base composition of the mitogenome is 40.61%, 7.66%, 40.34%, and 11.39%, respectively. The phylogenetic analyses recovered the monophyly of Aleocharinae.
RESUMO
To evaluate the dynamic characteristics at all positions of the main spindle of a machine tool, an experimental point was selected using a full factorial design, and a vibration test was conducted. Based on the measurement position, the resonant frequency was distributed from approximately 236 to 242 Hz. The approximation model was evaluated based on its resonant frequencies and dynamic stiffness using regression and interpolation methods. The accuracy of the resonant frequency demonstrated by the kriging method was approximately 89%, whereas the highest accuracy of the dynamic stiffness demonstrated by the polynomial regression method was 81%. To further verify the approximation model, its dynamic characteristics were measured and verified at additional experimental points. The maximum errors yielded by the model, in terms of the resonant frequency and dynamic stiffness, were 1.6% and 7.1%, respectively.
RESUMO
Although the physiological function of receptor-interacting protein kinase (RIPK) 3 has emerged as a critical mediator of programmed necrosis/necroptosis, the intracellular role it plays as an attenuator in human lungs and human bronchial epithelia remains unclear. Here, we show that the expression of RIPK3 dramatically decreased in the inflamed tissues of human lungs, and moved from the nucleus to the cytoplasm. The overexpression of RIPK3 dramatically increased F-actin formation and decreased the expression of genes for pro-inflammatory cytokines (IL-6 and IL-1ß), but not siRNA-RIPK3. Interestingly, whereas RIPK3 was bound to histone 1b without LPS stimulation, the interaction between them was disrupted after 15 min of LPS treatment. Histone methylation could not maintain the binding of RIPK3 and activated movement towards the cytoplasm. In the cytoplasm, overexpressed RIPK3 continuously attenuated pro-inflammatory cytokine gene expression by inhibiting NF-κB activation, preventing the progression of inflammation during Pseudomonas aeruginosa infection. Our data indicated that RIPK3 is critical for the regulation of the LPS-induced inflammatory microenvironment. Therefore, we suggest that RIPK3 is a potential therapeutic candidate for bacterial infection-induced pulmonary inflammation.
Assuntos
Lipopolissacarídeos , Pseudomonas aeruginosa , Humanos , Histonas , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Necrose , Inflamação/metabolismo , Citocinas/metabolismoRESUMO
An anatomical understanding of median nerve variation is essential for successful decompression of carpal tunnel syndrome (CTS). Although iatrogenic injury of the thenar branch after carpal tunnel release (CTR) has not been reported in many cases, it can cause serious damage to the patient. In case of rapidly progressing thenar atrophy after CTS surgery, thenar branch of median nerve injury should be suspected. Nerve conduction examination and ultrasound before surgery can be a useful tool for diagnosis.
RESUMO
Tissue-specific stem cells persist for a lifetime and can differentiate to maintain homeostasis or transform to initiate cancer. Despite their importance, there are no described quality assurance mechanisms for newly formed stem cells. We observed intimate and specific interactions between macrophages and nascent blood stem cells in zebrafish embryos. Macrophage interactions frequently led to either removal of cytoplasmic material and stem cell division or complete engulfment and stem cell death. Stressed stem cells were marked by surface Calreticulin, which stimulated macrophage interactions. Using cellular barcoding, we found that Calreticulin knock-down or embryonic macrophage depletion reduced the number of stem cell clones that established adult hematopoiesis. Our work supports a model in which embryonic macrophages determine hematopoietic clonality by monitoring stem cell quality.
Assuntos
Apoptose , Calreticulina , Comunicação Celular , Hematopoiese Clonal , Células-Tronco Hematopoéticas , Macrófagos , Animais , Calbindina 2/genética , Calbindina 2/fisiologia , Calreticulina/genética , Calreticulina/metabolismo , Hematopoiese Clonal/genética , Hematopoiese Clonal/fisiologia , Embrião não Mamífero , Células-Tronco Hematopoéticas/fisiologia , Macrófagos/fisiologia , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/fisiologiaRESUMO
BACKGROUND: The family Staphylinidae is the most speciose beetle group in the world. The outbreaks of two staphylinid species, Paederus fuscipes and Aleochara (Aleochara) curtula, were recently reported in South Korea. None of research about molecular markers and genetic diversity have been conducted in these two species. OBJECTIVE: To develop microsatellite markers and analyze the genetic diversity and population structures of two rove beetle species. METHODS: NGS was used to sequence whole genomes of two species, Paederus fuscipes and Aleochara (Aleochara) curtula. Microsatellite loci were selected with flanking primer sequences. Specimens of P. fuscipes and A. curtula were collected from three localities, respectively. Genetic diversity and population structure were analyzed using the newly developed microsatellite markers. RESULTS: The number of alleles ranged 5.727-6.636 (average 6.242) and 2.182-5.364 (average 4.091), expected heterozygosity ranged 0.560-0.582 (average 0.570) and 0.368-0.564 (average 0.498), observed heterozygosity ranged 0.458-0.497 (average 0.472) and 0.418-0.644 (average 0.537) in P. fuscipes and A. curtula, respectively. Population structure indicates that individuals of A. curtula are clustered to groups where they were collected, but those of P. fuscipes are not. CONCLUSION: Population structures of P. fuscipes were shallow. In A. curtula, however, it was apparent that the genetic compositions of the populations are different significantly depending on collection localities.
Assuntos
Besouros , Animais , Besouros/genética , Repetições de Microssatélites , Variação Genética/genética , República da CoreiaRESUMO
While sevoflurane and desflurane have been regarded as inhalation agents providing rapid induction and emergence, previous studies demonstrated the superiority of desflurane-anesthesia compared to sevoflurane-anesthesia in the postoperative recovery in obese and geriatric patients. We investigated whether a short-term switch of sevoflurane to desflurane at the end of sevoflurane-anesthesia enhances patient postoperative recovery profile in non-obese patients. We randomly divide patients undergoing elective surgery (n = 60) into two groups: sevoflurane-anesthesia group (Group-S, n = 30) and sevoflurane-desflurane group (Group-SD, n = 30). In Group-S, patients received only sevoflurane-anesthesia until the end of surgery (for >2 hours). In Group-SD, sevoflurane was stopped and switched to desflurane-anesthesia before the completion of sevoflurane-anesthesia (for approximately 30 minutes). We assessed the intergroup differences in the times to get eye-opening, extubation, and a bispectral index of 80 (BIS-80). Group-SD showed significantly shorter times to get eye-opening (438 ± 101 vs. 295 ± 45 s; mean difference, 143 s; 95% confidence interval [CI], 101-183; p < 0.001), extubation (476 ± 108 vs. 312 ± 42 s; mean difference, 164 s; 95% CI, 116-220; p < 0.001), and BIS-80 (378 ± 124 vs. 265 ± 49 minutes; mean difference, 113 s; 95% CI, 58-168 p < 0.001) compared to Group-S. There was no between-group difference in postoperative nausea, vomiting, and hypoxia incidences. Our results suggested that the short-term (approximately 30 minutes) switch of sevoflurane to desflurane at the end of sevoflurane-anesthesia can facilitate the speed of postoperative patient recovery.
Assuntos
Anestésicos Inalatórios , Isoflurano , Éteres Metílicos , Idoso , Período de Recuperação da Anestesia , Anestesia Geral , Anestésicos Inalatórios/farmacologia , Desflurano , Humanos , Isoflurano/farmacologia , Náusea e Vômito Pós-Operatórios , SevofluranoRESUMO
Magnetic resonance imaging (MRI)-guided magnetic nanofluid hyperthermia (MNFH) is highly desirable in cancer treatment because it can allow for diagnosis, therapeutics, and prognosis simultaneously. However, the application of currently developed iron-oxide based superparamagnetic nanoparticles (IOSPNPs) for an MRI-guided MNFH agent is technically limited by the low AC heat induction power at the physiologically tolerable range of AC magnetic field (HAC,safe), and the low transverser2-relaxivity responsible for the insufficient heating of cancers, and the low resolution of contrast imaging, respectively. Here, pseudo single domain colloidal NixZn1-x-γFe2O3(x = 0.6) superparamagnetic nanoparticle (NiZn-γFe2O3PSD-SPNP) physically and theoretically designed at theHAC,safe, specifically by the applied frequency, is proposed for a highly enhanced MRI-guided MNFH agent application. The NiZn-γFe2O3PSD-SPNP showed the superparamagnetic characteristics, significantly enhanced AC heat induction performance (ILP = 6.3 nHm2kg-1), highly improved saturation magnetization (Ms= 97 emu g-1Fe, 3.55 × 105A m-1) andr2-relaxivity (r2 = 396 mM-1s-1) that are desirable for highly efficient MRI-guided MNFH agent applications. According to the analyzed results, the remarkably enhanced effective relaxation time constant and its dependent out-of-phase magnetic susceptibility, as well as the DC/AC magnetic softness optimized by the PSD-SPNP at theHAC,safewere revealed as the main physical reason for the significance. All the fundamentalin vitroandin vivoexperimental results demonstrated that the physically designed NiZn-γFe2O3PSD-SPNP is bio-technically feasible for a highly efficient MRI-guided MNFH agent for future cancer nanomedicine.
Assuntos
Hipertermia Induzida/métodos , Imageamento por Ressonância Magnética/métodos , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , Coloides/química , Compostos Férricos/química , Humanos , Níquel/química , Compostos de Zinco/químicaRESUMO
BACKGROUND: This study assessed the effect of a single bolus administration of lidocaine on the prevention of tourniquet-induced hypertension (TIH) and compared the effect of lidocaine to that of ketamine in patients undergoing general anesthesia. METHODS: This randomized, controlled, double-blind study included 75 patients who underwent lower limb surgery using a tourniquet. The patients were administered lidocaine (1.5 mg/kg, n = 25), ketamine (0.2 mg/kg, n = 25) or placebo (n = 25). The study drugs were administered intravenously 10 min before tourniquet inflation. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before tourniquet inflation, after tourniquet inflation for 60 min at 10 min intervals, and immediately after tourniquet deflation. The incidence of TIH, defined as an increase of 30% or more in SBP or DBP during tourniquet inflation, was also recorded. RESULTS: SBP, DBP, and HR increased significantly over time in the control group compared to those in the lidocaine and ketamine groups for 60 min after tourniquet inflation (P < 0.001, P < 0.001, and P = 0.007, respectively). The incidence of TIH was significantly lower in the lidocaine (n = 4, 16%) and ketamine (n = 3, 12%) group than in the control group (n = 14, 56%) (P = 0.001). CONCLUSION: Single-bolus lidocaine effectively attenuated blood pressure increase due to tourniquet inflation, with an effect comparable to that of bolus ketamine.
RESUMO
Magnetic nanofluid hyperthermia (MNFH) with pure superparamagnetic nanoparticles (P-SPNPs) has drawn a huge attraction for cancer treatment modality. However, the low intrinsic loss power (ILP) and attributable degraded-biocompatibility resulting from the use of a heavy dose of P-SPNP agents as well as low heat induction efficiency in biologically safe AC magnetic field (HAC,safe) are challenging for clinical applications. Here, we report an innovatively designed pseudo-single domain-SPNP (PSD-SPNP), which has the same translational advantages as that of conventional P-SPNPs but generates significantly enhanced ILP at HAC,safe. According to the analyzed results, the optimized effective relaxation time, τeff, and magnetic out-of-phase susceptibility, χ'', precisely determined by the particle size at the specific frequency of HAC,safe are the main reasons for the significantly enhanced ILP. Additionally, in vivo MNFH studies with colloidal PSD-SPNPs strongly demonstrated that it can be a promising agent for clinically safe MNFH application with high efficacy.
Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Nanopartículas , Campos Magnéticos , Nanopartículas Magnéticas de Óxido de Ferro , MagnetismoRESUMO
Reliable measurement of heating power of magnetic nanofluids (MNs) to accurately predict the AC heat-induction performance in tumors is highly desirable for clinical magnetic nanofluids hyperthermia (MNFH) application because it can save time for screening the performance of newly developed MNFH agent and minimize the over-use of animals dramatically. Here, a bio-mimicking phantom model, called Pseudo-Tumor Environment System (P-TES), biochemically designed by considering the external and internal critical factors related to the complex biological environments is proposed to provide a highly reliable evaluation method of heating performance of MNs for in-vivo MNFH applications. According to the experimentally analyzed results, the heating power of MNs measured using the P-TES is well accorded with the heating temperature measured in the tumors during in-vivo MNFH. This result strongly demonstrates that the proposed P-TES can be recommended as a standardized measurement method of heating performance of MNs for clinical MNFH application.
Assuntos
Hipertermia Induzida/métodos , Nanopartículas de Magnetita/uso terapêutico , Neoplasias/terapia , Algoritmos , Calefação , Humanos , Magnetismo , Nanomedicina , NanotecnologiaRESUMO
In the case of a cat bite patient, even if the external wound is small, prophylactic antibiotics should be used early and a closed observation is needed. If symptoms persist, deep infection should be considered.