Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 259
Filtrar
1.
Res Pract Thromb Haemost ; 8(4): 102463, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-39026660

RESUMEN

Background: Thrombin activatable fibrinolysis inhibitor (TAFI) is one of the most important physiological fibrinolysis inhibitors. Its inhibitory efficacy under physiological conditions remains uncertain. Objectives: Elucidate the role of soluble thrombomodulin (sTM)/TAFI axis in the regulation of fibrinlysis. Methods: Since thrombin is required to generate activated TAFI (TAFIa) that targets the C-terminal lysine of partially digested fibrin, a clot lysis assay is suitable for evaluating its function. Using tissue-type plasminogen activator-induced plasma clot lysis time (tPA-PCLT) together with TAFIa inhibitor and recombinant sTM (rsTM), we evaluated the specific function of TM/TAFI in the plasma milieu. Results: tPA-PCLT values were significantly shortened by the TAFIa inhibitor. rsTM supplementation prolonged tPA-PCLT, which was shortened by the TAFIa inhibitor to a time similar to that obtained without rsTM and with the TAFIa inhibitor. Plasma obtained from patients treated with rsTM showed prolonged tPA-PCLT, which was shortened by the TAFIa inhibitor but not further prolonged by rsTM. However, no significant correlation was observed between tPA-PCLT and parameters of TM/TAFI system in the plasma. Conclusion: The role of the TM/TAFI system in regulating fibrinolysis was successfully evaluated using TAFIa inhibitor and rsTM. Trace amounts of soluble TM in normal plasma appeared sufficient to activate TAFI and inhibit fibrinolysis. Further, a therapeutic dose of rsTM appeared sufficient to activate TAFI and regulate fibrinolysis in the plasma milieu.

2.
Neurobiol Aging ; 141: 14-20, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38796942

RESUMEN

Physiological age-related alterations in the interstitial flow in the brain, which plays an important role in waste product removal, remain unclear. Using [15O]H2O positron emission tomography (PET), water dynamics were evaluated in 63 healthy adult participants aged between 20 and 80 years. Interstitial flow was assessed by influx ratio (IR) and drain rate (DR), using time-activity concentration data. Participants were divided into four age groups with 15-year ranges, to evaluate age-related functional alterations. At least one of the indices declined significantly with age across all groups. A significant linear negative correlation between age and both indicators was found in the scatter plots (IR: R2 = 0.54, DR: R2 = 0.44); both indicators were predominantly lower after age 50 years. These results suggest interstitial flow decreases with age, especially after 50 years. These important findings can contribute to devising therapeutic interventions for neurological diseases characterized by abnormal accumulation of waste products, and suggest the need for taking measures to maintain interstitial flow starting around the age of 50 years.


Asunto(s)
Envejecimiento , Encéfalo , Líquido Extracelular , Tomografía de Emisión de Positrones , Humanos , Persona de Mediana Edad , Anciano , Adulto , Masculino , Femenino , Envejecimiento/fisiología , Líquido Extracelular/fisiología , Anciano de 80 o más Años , Adulto Joven , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología
3.
J Physiol Sci ; 74(1): 26, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654149

RESUMEN

Purines such as ATP are regulatory transmitters in motility of the gastrointestinal tract. The aims of this study were to propose functional roles of purinergic regulation of esophageal motility. An isolated segment of the rat esophagus was placed in an organ bath, and mechanical responses were recorded using a force transducer. Exogenous application of ATP (10-100 µM) evoked relaxation of the esophageal smooth muscle in a longitudinal direction under the condition of carbachol (1 µM) -induced precontraction. Pretreatment with a non-selective P2 receptor antagonist, suramin (500 µM), and a P2Y receptor antagonist, cibacron blue F3GA (200 µM), inhibited the ATP (100 µM) -induced relaxation, but a P2X receptor antagonist, pyridoxal phosphate-6-azophenyl-2,4-disulfonic acid (50 µM), did not affect it. A blocker of ATP-dependent potassium channels (KATP channels), glibenclamide (200 µM), inhibited the ATP-induced relaxation and application of an opener of KATP channels, nicorandil (50 µM), produced relaxation. The findings suggest that ATP is involved in inhibitory regulation of the longitudinal smooth muscle in the muscularis mucosae of the rat esophagus via activation of P2Y receptors and then opening of KATP channels.


Asunto(s)
Adenosina Trifosfato , Esófago , Canales KATP , Músculo Liso , Receptores Purinérgicos P2Y , Animales , Ratas , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Músculo Liso/metabolismo , Masculino , Receptores Purinérgicos P2Y/metabolismo , Esófago/efectos de los fármacos , Esófago/fisiología , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Canales KATP/metabolismo , Relajación Muscular/efectos de los fármacos , Relajación Muscular/fisiología , Ratas Wistar , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Antagonistas del Receptor Purinérgico P2Y/farmacología , Motilidad Gastrointestinal/efectos de los fármacos , Motilidad Gastrointestinal/fisiología , Ratas Sprague-Dawley
5.
Int J Mol Sci ; 25(4)2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38396664

RESUMEN

The tunica muscularis of mammalian esophagi is composed of striated muscle and smooth muscle. Contraction of the esophageal striated muscle portion is mainly controlled by cholinergic neurons. On the other hand, smooth muscle contraction and relaxation are controlled not only by cholinergic components but also by non-cholinergic components in the esophagus. Adenosine triphosphate (ATP) is known to regulate smooth muscle contraction and relaxation in the gastrointestinal tract via purinergic receptors. However, the precise mechanism of purinergic regulation in the esophagus is still unclear. Therefore, the aim of the present study was to clarify the effects of ATP on the mechanical responses of the esophageal muscle in mice. An isolated segment of the mouse esophagus was placed in a Magnus's tube and longitudinal mechanical responses were recorded. Exogenous application of ATP induced contractile responses in the esophageal preparations. Tetrodotoxin, a blocker of voltage-dependent sodium channels in neurons and striated muscle, did not affect the ATP-induced contraction. The ATP-evoked contraction was blocked by pretreatment with suramin, a purinergic receptor antagonist. RT-PCR revealed the expression of mRNA of purinergic receptor genes in the mouse esophageal tissue. The findings suggest that purinergic signaling might regulate the motor activity of mouse esophageal smooth muscle.


Asunto(s)
Adenosina Trifosfato , Músculo Estriado , Ratones , Animales , Adenosina Trifosfato/farmacología , Contracción Muscular/fisiología , Esófago , Músculo Estriado/fisiología , Receptores Purinérgicos , Músculo Liso , Mamíferos
6.
Neoplasia ; 50: 100982, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38417223

RESUMEN

Glioblastoma is the deadliest form of brain tumor. The presence of the blood-brain barrier (BBB) significantly hinders chemotherapy, necessitating the development of innovative treatment options for this tumor. This report presents the in vitro and in vivo efficacy of an antibody-drug conjugate (ADC) that targets glypican-1 (GPC1) in glioblastoma. The GPC1-ADC was created by conjugating a humanized anti-GPC1 antibody (clone T2) with monomethyl auristatin E (MMAE) via maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl linkers. Immunohistochemical staining analysis of a glioblastoma tissue microarray revealed that GPC1 expression was elevated in more than half of the cases. GPC1-ADC, when bound to GPC1, was efficiently and rapidly internalized in glioblastoma cell lines. It inhibited the growth of GPC1-positive glioma cell lines by inducing cell cycle arrest in the G2/M phase and triggering apoptosis in vitro. We established a heterotopic xenograft model by subcutaneously implanting KALS-1 and administered GPC1-ADC intravenously. GPC1-ADC significantly inhibited tumor growth and increased the number of mitotic cells. We also established an orthotopic xenograft model by intracranially implanting luciferase-transfected KS-1-Luc#19. After injecting Evans blue and resecting brain tissues, dye leakage was observed in the implantation area, confirming BBB disruption. We administered GPC1-ADC intravenously and measured the luciferase activity using an in vivo imaging system. GPC1-ADC significantly inhibited tumor growth and extended survival. In conclusion, GPC1-ADC demonstrated potent intracranial activity against GPC1-positive glioblastoma in an orthotopic xenograft model. These results indicate that GPC1-ADC could represent a groundbreaking new therapy for treating glioblastoma beyond the BBB.


Asunto(s)
Glioblastoma , Inmunoconjugados , Humanos , Inmunoconjugados/farmacología , Glioblastoma/tratamiento farmacológico , Línea Celular Tumoral , Glipicanos/metabolismo , Luciferasas , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Int J Cancer ; 154(3): 425-433, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37728485

RESUMEN

Lipolysis-stimulated lipoprotein receptor (LSR) is known as a lipoprotein receptor. LSR is expressed in various solid tumors, including epithelial ovarian, gastric, and colon cancers. High LSR expression is significantly associated with poor prognosis, but its role in cancer has not been fully elucidated. LSR belongs to the Ig protein superfamily, which is conserved in B7 family. Here, we assessed LSR as a novel immune checkpoint molecule. We developed a novel anti-LSR antibody (#27-6 mF-18) that defects antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity activity. The #27-6 mF-18 cross-reacts with both human and mouse LSR. We found that LSR was expressed on 4T1 murine breast cancer cell line. The #27-6 mF-18 exhibited antitumor effects against the 4T1 syngeneic tumor model, a poor immunogenic model refractory to treatment with anti-PD-1 or anti-CTLA-4 antibodies. Compared with control antibody-treated mice, mice treated with #27-6 mF-18 showed significantly increased numbers of CD8+ T cells and a ratio of activated CD8+ T cells infiltrated in the tumor tissue. This antitumor effect was abrogated by CD8+ T-cell depletion through anti-CD8 antibody treatment, indicating that LSR negatively regulates tumor immunity by repressing CD8+ T cells. These findings show that LSR negatively regulates T-cell immune activity. LSR targeting could provide immune checkpoint inhibitors for cancer immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos , Receptores de Lipoproteína , Humanos , Ratones , Animales , Linfocitos T CD8-positivos/metabolismo , Lipólisis , Proteínas/metabolismo , Receptores de Lipoproteína/metabolismo , Células MCF-7 , Línea Celular Tumoral
8.
J Plant Res ; 137(2): 255-264, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38112982

RESUMEN

The kinetic properties of Rubisco, a key enzyme for photosynthesis, have been examined in numerous plant species. However, this information on some plant groups, such as ferns, is scarce. This study examined Rubisco carboxylase activity and leaf Rubisco levels in seven ferns, including four Equisetum plants (E. arvense, E. hyemale, E. praealtum, and E. variegatum), considered living fossils. The turnover rates of Rubisco carboxylation (kcatc) in E. praealtum and E. hyemale were comparable to those in the C4 plants maize (Zea mays) and sorghum (Sorghum bicolor), whose kcatc values are high. Rubisco CO2 affinity, estimated from the percentage of Rubisco carboxylase activity under CO2 unsaturated conditions in kcatc in these Equisetum plants, was low and also comparable to that in maize and sorghum. In contrast, kcatc and CO2 affinities of Rubisco in other ferns, including E. arvense and E. variegatum were comparable with those in C3 plants. The N allocation to Rubisco in the ferns examined was comparable to that in the C3 plants. These results indicate that E. praealtum and E. hyemale have abundant Rubisco with high kcatc and low CO2 affinity, whereas the carboxylase activity and abundance of Rubisco in other ferns were similar to those in C3 plants. Herein, the Rubisco properties of E. praealtum and E. hyemale were discussed regarding their evolution and physiological implications.


Asunto(s)
Equisetum , Ribulosa-Bifosfato Carboxilasa , Dióxido de Carbono , Equisetum/metabolismo , Fotosíntesis/fisiología , Plantas/metabolismo , Zea mays/metabolismo
10.
Environ Monit Assess ; 195(12): 1437, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37940732

RESUMEN

To clarify the characteristics of compounds with strong or weak nitrification inhibition in sewage, 64 organic compounds including compounds registered in Pollutant Release and Transfer Register (PRTR) were evaluated in terms of their chemical structures and molecular weights. Nineteen compounds showed strong nitrification inhibition by testing with Nitrosomonas europaea. Compounds with thioamide structures had the lowest median value of EC50 (0.017 mg/L), followed by those with alkyne structures (0.121 mg/L), chlorophenol structures (0.300 mg/L), and then azole structures (0.365 mg/L). In contrast, 33 of the 64 compounds showed weak nitrification inhibition at a concentration of 10 mg/L, 27 of which were categorized into three main groups: long-chain alcohol structures, alkyne structures with a phenyl group, and aromatic structures. Most compounds with strong nitrification inhibition had a low molecular weight (MW) from 50 to 200. Meanwhile, the proportion of compounds with weak nitrification inhibition tended to be greater with increasing MW and such compounds were predominant at higher molecular weights above 300. The correlations of results derived from tests of nitrification inhibition based on ISO 9509 and N. europaea showed that 24 out of 30 compounds provided results that were highly correlated between these tests (R = 0.85), while 4 compounds with chlorophenol structures and 2 compounds with alkyne structures showed weaker inhibition rates in the ISO 9509 test than in the N. europaea test. Our results indicate that the magnitude of nitrification inhibition depends on MW in addition to the chemical structure, which is helpful in the search for the cause of nitrification inhibition in wastewater treatment plants.


Asunto(s)
Clorofenoles , Aguas del Alcantarillado , Nitrificación , Reactores Biológicos , Monitoreo del Ambiente , Alquinos , Oxidación-Reducción
11.
Invest Ophthalmol Vis Sci ; 64(12): 22, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37698528

RESUMEN

Purpose: Water inflow into the vitreous body regulated by retinal aquaporin-4 distributed within Müller cells has been observed in mice; however, the changes in this phenomenon with age remain unknown. This study aimed to evaluate whether intravenously injected H2O also flows into the vitreous body of human subjects and to investigate whether water dynamics in the human posterior eye change with age using [15O]H2O positron emission tomography (PET). Methods: Forty-six normal adult volunteers underwent [15O]H2O PET, and the standard uptake value (SUV) in the center of the vitreous body after 1000-MBq [15O]H2O administration was assessed. The SUV was fitted to an exponential curve, and y0, the steady state of the SUV, and b, the speed of increase in the SUV, were calculated. The results for patients ranging from in age from 20 to 39, 40 to 59, and 60 to 79 years were compared using analyses of variance followed by Games to Howell tests. Results: For the parameter y0, statistical analysis revealed no statistically significant differences among the three groups. For parameter b, statistical analysis revealed statistically significant differences between the 20 to 39 and 60 to 79 age groups (P = 0.000), the 40 to 59 and 60 to 79 age groups (P = 0.025), and the 20 to 39 and 40 to 59 age groups (P = 0.037). Conclusions: The present study revealed that H2O injected into the vein flows into the human vitreous body and that the speed of increase in water flow into the vitreous body decreases with aging. This study suggests that water dynamics in the posterior eye, or the retinal glymphatic pathway, change significantly with aging.


Asunto(s)
Envejecimiento , Cuerpo Vítreo , Adulto , Humanos , Animales , Ratones , Adulto Joven , Cuerpo Vítreo/diagnóstico por imagen , Acuaporina 4 , Transporte Biológico
12.
Sci Rep ; 13(1): 15026, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37700060

RESUMEN

Hyperphosphatemia is a major risk for poor prognosis in patients with end-stage renal disease. However, the molecular mechanism behind this link remains elusive. We and others have demonstrated that serum phosphorus levels correlate positively with circulating levels of calciprotein particles (CPPs). CPPs are colloidal mineral-protein complexes containing insoluble calcium-phosphate precipitates and have been reported to induce calcification in cultured vascular smooth muscle cells and inflammatory responses in cultured macrophages. Hence, we hypothesize that CPPs may be responsible for disorders associated with hyperphosphatemia. Using hyperphosphatemic miniature pigs receiving hemodialysis, here we show that removal of CPPs from the blood with a newly developed CPP adsorption column improves survival and alleviates complications including coronary artery calcification, vascular endothelial dysfunction, metastatic pulmonary calcification, left ventricular hypertrophy, and chronic inflammation. The present study identifies CPPs as an effective therapeutic target and justifies clinical trials to determine whether the CPP adsorption column may be useful as a medical device for improving clinical outcomes of hemodialysis patients.


Asunto(s)
Calcinosis , Coristoma , Hiperfosfatemia , Animales , Porcinos , Porcinos Enanos , Adsorción , Pronóstico , Diálisis Renal , Calcinosis/terapia
13.
Front Neurol ; 14: 1215004, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37554393

RESUMEN

Introduction: Persistent postural-perceptual dizziness (PPPD) is a functional chronic vestibular syndrome with symptom exacerbation by upright posture, motion, and complex visual stimuli. Among these exacerbating factors, visual exacerbation is the most specific characteristic of PPPD requiring further investigation. We hypothesized that stimulus-induced changes occur in the functional connectivity (FC) rather than simple neural activation that is involved in visual stimulation. The present study aimed to identify the neural basis of PPPD by investigating FC before and after visual stimulation. Methods: Eleven patients with PPPD and 11 age- and sex-matched healthy controls (HCs) underwent resting-state fMRI (rs-fMRI) before and after task-based fMRI with visual stimuli. Results: At pre-stimulus, FC between the vestibular cortex and visual areas was low, while that between the somatosensory and visual areas was high in PPPD compared with that in HCs. FC between the visuospatial (parahippocampal gyrus) and spatial cognitive areas (inferior parietal lobule) was elevated in PPPD even in the pre-stimulus condition, which no longer increased at post-stimulus as observed in HCs. In the post-stimulus condition, FC between the visual and spatial cognitive areas and that between the visual and prefrontal areas increased compared with that in the pre-stimulus condition in PPPD. Task-based fMRI demonstrated that no brain regions showed different activities between the HC and PPPD groups during visual stimulation. Discussion: In PPPD, vestibular inputs may not be fully utilized in the vestibulo-visuo-somatosensory network. Given that the FC between visuospatial and spatial cognitive areas increased even in HCs after visual stimuli, elevated status of this FC in combination with the high FC between the somatosensory and visual areas would be involved in the visual exacerbation in PPPD. An increase in FC from the visual areas to spatial cognitive and prefrontal areas after visual stimuli may account for the prolonged symptoms after visual exacerbation and anxious status in PPPD.

14.
Adv Mater ; : e2303827, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37452693

RESUMEN

Electret materials are promising dielectric materials with trapped charges for various applications such as vibration energy harvesters and acoustic transducers. In the present work, ionization potential is discovered as the descriptor to quantify the charging performance for amorphous fluorinated polymer electrets. Using this descriptor, high-throughput computations, and graph neural network models, 1 176 591 functional groups are screened on the cyclic transparent optical polymers (CYTOP), and 3 promising electrets are identified. The electrets are synthesized experimentally as 15 µm-thick films. The films are able to keep their both bipolar surface potentials above ±3.1 kV for over 1500 h and are estimated to have longevity of 146 years under 80 °C, achieving significant improvements on charging stability among CYTOP-based polymer electrets. The excellent bipolar charging performance can greatly enhance power generation capacity of electret-based vibration energy harvesters. This work also demonstrates the use of deep learning as a new paradigm for accelerating practical materials discovery.

15.
Oncology ; 101(11): 714-722, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37369179

RESUMEN

INTRODUCTION: Systemic therapy provides clinical benefits to a subset of patients with advanced unresectable hepatocellular carcinoma (HCC). However, few biomarkers are available for predicting prognosis and treatment response in patients with advanced HCC undergoing treatment with systemic therapies. This study aimed to examine whether circulating cell-free DNA (cfDNA) containing circulating tumor DNA can act as a therapeutic response and prognostic biomarker in patients with advanced HCC. METHODS: We analyzed longitudinally collected plasma cfDNA of patients with advanced HCC who were naïve to systemic therapy, and assessed their prognostic and predictive values to determine treatment responses. RESULTS: cfDNA concentration positively correlated with entire tumor volume on computed tomography before (p = 0.0231) and at the end (p < 0.0001) of the first-line systemic therapy. The overall survival rate was higher in patients with cfDNA concentrations lower than the median cfDNA level at baseline compared to patients with higher cfDNA concentrations (hazard ratio, 0.2765; 95% confidence interval, 0.08-0.81; p = 0.0197). The ratio of cfDNA at 4 weeks to that at baseline was predictive of radiographic disease response. In patients with progressive disease, cfDNA concentration at 4 weeks increased significantly (p = 0.0245), whereas the concentration remained unchanged in patients with other disease courses (p = 0.9375). CONCLUSION: The baseline plasma cfDNA concentration can be used as a prognostic biomarker in patients with advanced HCC. cfDNA kinetics may also predict the tumor response to therapy and disease progression.

16.
Clin J Oncol Nurs ; 27(3): 289-294, 2023 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-37267487

RESUMEN

BACKGROUND: Measures to prevent exposure to anticancer drugs mitigate health hazards for caregivers, family members, and healthcare workers caring for patients with cancer. Previous studies have reported that anticancer drugs were detected on the linens of patients receiving chemotherapy. OBJECTIVES: This pilot study investigated the effectiveness of the washing methods recommended by Japanese guidelines for linens contaminated with cyclophosphamide (CTX). METHODS: This study used 15 shirts contaminated with 10 mg of CTX divided into three study groups washed with or without detergent, with or without an additional clean shirt. The CTX level on each shirt was measured after washing. Residual CTX levels on the shirts were compared to the measurable level of 1 ng/cm2 as a criterion for evaluating efficacy. FINDINGS: Washing a garment twice, as recommended in the Japanese guidelines, is effective in removing CTX contamination from clothing with or without detergent. However, contaminated garments should be washed separately from uncontaminated clothing.


Asunto(s)
Antineoplásicos , Detergentes , Humanos , Proyectos Piloto , Detergentes/uso terapéutico , Ciclofosfamida/uso terapéutico , Ciclofosfamida/análisis , Vestuario
17.
JA Clin Rep ; 9(1): 30, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37227540

RESUMEN

BACKGROUND: Perinatal management of congenital platelet dysfunction represents a challenge. One of the major concerns is whether neuraxial anesthesia can be applicable for cesarean delivery. We present a patient with thrombasthenia who underwent emergency cesarean delivery. CASE PRESENTATION: A 34-year-old primipara was diagnosed with autosomal dominant thrombasthenia, which was not classified as any known type. A thorough examination revealed that adenosine diphosphate aggregation and collagen aggregation were suppressed. Platelet mapping of viscoelastic testing was used to observe the trajectory of platelet function during pregnancy, which was found to be normal to hypercoagulable until 38 weeks of gestation. On the basis of the results of testing and physiological status, we commenced spinal anesthesia and avoided prophylactic platelet transfusion. CONCLUSION: The platelet mapping of viscoelastic testing was rapid and simple, allowing repeated examinations. We could choose the appropriate anesthesia method and determine the necessity of blood transfusion for a pregnant patient with thrombasthenia.

18.
Exp Neurol ; 366: 114444, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37196696

RESUMEN

Axons of terminally differentiated neurons in the mammalian central nervous system (CNS) are unable to regenerate after dissection. One of the mechanisms underlying this is the inhibition of axonal regeneration by chondroitin sulfate (CS) and its neuronal receptor, PTPσ. Our previous results demonstrated that the CS-PTPσ axis disrupted autophagy flux by dephosphorylating cortactin, which led to the formation of dystrophic endballs and to the inhibition of axonal regeneration. In contrast, juvenile neurons vigorously extend axons toward their targets during development and maintain regenerative activity for axons even after injury. Although several intrinsic and extrinsic mechanisms have been reported to mediate the differences, the detailed mechanisms are still elusive. Here, we report that Glypican-2, a member of heparan sulfate proteoglycans (HSPG), which are able to antagonize CS-PTPσ by competing with the receptor, is specifically expressed in the axonal tips of embryonic neurons. Glypican-2 overexpression in adult neurons rescues the dystrophic endball back to a healthy growth cone on the CSPG gradient. Consistently, Glypican-2 restored cortactin phosphorylation in the axonal tips of adult neurons on CSPG. Taken together, our results clearly demonstrated Glypican-2's pivotal role in defining the axonal response to CS and provided a new therapeutic target for axonal injury.


Asunto(s)
Sulfatos de Condroitina , Glipicanos , Animales , Sulfatos de Condroitina/farmacología , Cortactina , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Axones/fisiología , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Regeneración Nerviosa/fisiología , Mamíferos
19.
Plant J ; 115(4): 1004-1020, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37162489

RESUMEN

Photorespiration is an essential metabolic mechanism associated with photosynthesis; however, little is known about the photorespiratory pathway of conifer gymnosperms. Metabolite analyses of the leaves of 27 tree species showed that the mean glycerate content in conifer leaves was lower than that in angiosperm leaves. We performed experiments where [13 C]-serine was fed to detached shoots of a conifer (Cryptomeria japonica), via the transpiration stream, and compared the labeling patterns of photorespiratory metabolites with those of an angiosperm tree (Populus nigra), because glycerate is produced from serine via hydroxypyruvate in peroxisomes. In P. nigra, hydroxypyruvate, glycerate and glycine were labeled with 13 C, whereas in C. japonica, glycolate and a non-canonical photorespiratory metabolite, formate, were also labeled, suggesting that an H2 O2 -mediated non-enzymatic decarboxylation (NED) reaction occurs in C. japonica. We analyzed changes in the metabolite contents of leaves kept in the dark and leaves exposed to illuminated photorespiration-promoting conditions: a positive relationship between formate and serine levels in C. japonica implied that the active C1 -metabolism pathway synthesizes serine from formate. Leaf gas exchange analyses revealed that CO2 produced through NED was recaptured by chloroplasts. Database analysis of the peroxisomal targeting signal motifs of an H2 O2 -scavenging enzyme, catalase, derived from various species, including nine coniferous species, as well as analyses of peroxisomal fractions isolated from C. japonica and P. nigra leaves indicated that conifer peroxisomes had less catalase activity. These results suggest that NED and the subsequent C1 metabolism are involved in the photorespiratory pathway of conifer leaves, where peroxisomes have intrinsically low catalase activity.


Asunto(s)
Magnoliopsida , Tracheophyta , Peroxisomas/metabolismo , Tracheophyta/metabolismo , Catalasa/metabolismo , Fotosíntesis , Magnoliopsida/metabolismo , Hojas de la Planta/metabolismo , Serina/metabolismo
20.
Infect Dis Rep ; 15(1): 142-149, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36826355

RESUMEN

In hospitals, outbreaks can occur due to pathogens accumulating in the areas around the wards' washbasins. Carbapenem-resistant Enterobacterales (CRE) was detected in an environmental survey in the high-care unit of a university hospital in Isehara, Japan, and effective cleaning methods were investigated. This study investigated methods of cleaning taps using commonly used detergents and disinfectants, and it assessed their effectiveness in removing hard scale and pathogens, including CRE. The taps were cleaned using various methods and cleaning agents, including environmentally neutral detergent, citric acid, baking soda, cleanser, 80% ethanol, 0.1% sodium hypochlorite, and a phosphoric acid-based environmental detergent (Space Shot). The cleaning effect was assessed based on the agent's effectiveness at removing hard scale from taps. Biofilms and scale were identified on taps, and several bacterial species were cultured. Only phosphoric acid-based detergent was effective at removing hard scale. After cleaning with the phosphoric acid-based detergent, the bacterial count decreased, and no CRE or other pathogens were detected. These results provide a reference for other facilities considering introducing this cleaning method.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...