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1.
EBioMedicine ; 109: 105390, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39383607

RESUMEN

BACKGROUND: Macrophages engineered with chimeric antigen receptors (CAR) are suitable for immunotherapy based on their immunomodulatory activity and ability to infiltrate solid tumours. However, the production and application of genetically edited, highly effective, and mass-produced CAR-modified macrophages (CAR-Ms) are challenging. METHODS: Here, we used homology-independent targeted insertion (HITI) for site-directed CAR integration into the safe-harbour region of human pluripotent stem cells (hPSCs). This approach, together with a simple differentiation protocol, produced stable and highly effective CAR-Ms without heterogeneity. FINDINGS: These engineered cells phagocytosed cancer cells, leading to significant inhibition of cancer-cell proliferation in vitro and in vivo. Furthermore, the engineered CARs, which incorporated a combination of CD3ζ and Megf10 (referred to as FRP5Mζ), markedly enhanced the antitumour effect of CAR-Ms by promoting M1, but not M2, polarisation. FRP5Mζ promoted M1 polarisation via nuclear factor kappa B (NF-κB), ERK, and STAT1 signalling, and concurrently inhibited STAT3 signalling even under M2 conditions. These features of CAR-Ms modulated the tumour microenvironment by activating inflammatory signalling, inducing M1 polarisation of bystander non-CAR macrophages, and enhancing the infiltration of T cells in cancer spheroids. INTERPRETATION: Our findings suggest that CAR-Ms have promise as immunotherapeutics. In conclusion, the guided insertion of CAR containing CD3ζ and Megf10 domains is an effective strategy for the immunotherapy of solid tumours. FUNDING: This work was supported by KRIBB Research Initiative Program Grant (KGM4562431, KGM5282423) and a Korean Fund for Regenerative Medicine (KFRM) grant funded by the Korean government (Ministry of Science and ICT,Ministry of Health and Welfare) (22A0304L1-01).

2.
Mol Med ; 30(1): 143, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256649

RESUMEN

BACKGROUND: Targeting the tumor microenvironment represents an emerging therapeutic strategy for cancer. Macrophages are an essential part of the tumor microenvironment. Macrophage polarization is modulated by mitochondrial metabolism, including oxidative phosphorylation (OXPHOS), the tricarboxylic acid (TCA) cycle, and reactive oxygen species content. Isocitrate dehydrogenase 2 (IDH2), an enzyme involved in the TCA cycle, reportedly promotes cancer progression. However, the mechanisms through which IDH2 influences macrophage polarization and modulates tumor growth remain unknown. METHODS: In this study, IDH2-deficient knockout (KO) mice and primary cultured bone marrow-derived macrophages (BMDMs) were used. Both in vivo subcutaneous tumor experiments and in vitro co-culture experiments were performed, and samples were collected for analysis. Western blotting, RNA quantitative analysis, immunohistochemistry, and flow cytometry were employed to confirm changes in mitochondrial function and the resulting polarization of macrophages exposed to the tumor microenvironment. To analyze the effect on tumor cells, subcutaneous tumor size was measured, and growth and metastasis markers were identified. RESULTS: IDH2-deficient macrophages co-cultured with cancer cells were found to possess increased mitochondrial dysfunction and fission than wild-type BMDM. Additionally, the levels of M2-associated markers decreased, whereas M1-associated factor levels increased in IDH2-deficient macrophages. IDH2-deficient macrophages were predominantly M1. Tumor sizes in the IDH2-deficient mouse group were significantly smaller than in the wild-type mouse group. IDH2 deficiency in macrophages was associated with inhibited tumor growth and epithelial-mesenchymal transition. CONCLUSIONS: Our findings suggest that IDH2 deficiency inhibits M2 macrophage polarization and suppresses tumorigenesis. This study underlines the potential contribution of IDH2 expression in macrophages and tumor microenvironment remodeling, which could be useful in clinical cancer research.


Asunto(s)
Isocitrato Deshidrogenasa , Macrófagos , Mitocondrias , Microambiente Tumoral , Animales , Humanos , Ratones , Carcinogénesis/metabolismo , Carcinogénesis/genética , Carcinogénesis/patología , Línea Celular Tumoral , Técnicas de Cocultivo , Isocitrato Deshidrogenasa/metabolismo , Isocitrato Deshidrogenasa/genética , Activación de Macrófagos , Macrófagos/metabolismo , Ratones Noqueados , Mitocondrias/metabolismo
3.
Surg Endosc ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39327294

RESUMEN

BACKGROUND: In standard colonoscopic examinations, some polyps may be missed during the withdrawal phase. Re-examination of the right colon can improve the adenoma detection rate (ADR). However, the effectiveness of applying this re-examination strategy to the entire colon remains unknown. We investigated whether re-examination could increase the detection rate of polyps and adenomas throughout the colon. METHODS: A randomized, controlled, single-center trial (NCT03268200) was conducted in a university hospital. Patients aged 45-75 years were randomly assigned to either the study or control group. For patients in the control group, observation and polypectomy were performed once using the standard colonoscopy method. For patients in the study group, polypectomy was repeated twice during the withdrawal phase after the initial insertion of the colonoscope. These examinations were performed in the right transverse and left colons. The primary endpoints were the polyp detection rate (PDR) and ADR, defined as the proportion of patients with ≥ 1 polyp and ≥ 1 adenoma, respectively. RESULTS: Overall, 406 patients were enrolled (study group, n = 210; control group, n = 196) and analyzed. Generally, PDRs and ADRs were similar between the study (withdrawal 1 + 2) and control groups (withdrawal 1), except for the right colon. However, the second withdrawal review increased number of polyps and adenomas in the overall, right, mid, and left colon, respectively. CONCLUSION: The results of this trial indicated that re-examination of the entire colon during colonoscopy could be beneficial for detecting concealed polyps in patients at risk of interval cancer.

4.
Cell Mol Biol (Noisy-le-grand) ; 70(7): 8-14, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39097901

RESUMEN

Alzheimer's disease (AD) is the most common neurodegenerative disorder, and amyloid beta oligomers (AßO), which are pathological markers of AD, are known to be highly toxic. AßO increase mitochondrial dysfunction, which is accompanied by a decrease in mitochondrial fusion. Although mitofusin (Mfn) 1 and Mfn2 are mitochondrial fusion proteins, Mfn2 is known to regulate endoplasmic reticulum (ER) function, as it is located in the ER. Several studies have shown that AßO exacerbates ER stress, however, the exact mechanism requires further elucidation. In this study, we used mouse neuroblastoma cells stably overexpressing the amyloid precursor protein (APP) with the Swedish mutation (N2a APPswe cells) to investigate the role of Mfn in ER stress. Our results revealed that  amyloid beta (Aß) caused cellular toxicity in N2a APPswe cells, upregulated ER stress-related proteins, and promoted ER expansion. The AßO-mediated ER stress was reduced when Mfn1 and Mfn2 were overexpressed. Moreover, Mfn1 and Mfn2 overexpressed resulted in reduced apoptosis of N2a APPswe cells. In conclusion, our results indicate that both Mfn1 and Mfn2 reduce ER stress and apoptosis. Our data provide a foundation for future studies on the roles of Mfn1 and Mfn2 in the molecular mechanisms underlying AßO-mediated ER stress and the pathogenesis of AD.


Asunto(s)
Péptidos beta-Amiloides , Apoptosis , Estrés del Retículo Endoplásmico , GTP Fosfohidrolasas , Animales , Humanos , Ratones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Apoptosis/genética , Línea Celular Tumoral , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico/genética , GTP Fosfohidrolasas/metabolismo , GTP Fosfohidrolasas/genética , Mitocondrias/metabolismo
5.
Sci Rep ; 14(1): 15642, 2024 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977865

RESUMEN

Oxidative stress plays an essential role in the progression of Alzheimer's disease (AD), the most common age-related neurodegenerative disorder. Streptozotocin (STZ)-induced abnormal brain insulin signaling and oxidative stress play crucial roles in the progression of Alzheimer's disease (AD)-like pathology. Peroxiredoxins (Prxs) are associated with protection from neuronal death induced by oxidative stress. However, the molecular mechanisms underlying Prxs on STZ-induced progression of AD in the hippocampal neurons are not yet fully understood. Here, we evaluated whether Peroxiredoxin 1 (Prx1) affects STZ-induced AD-like pathology and cellular toxicity. Prx1 expression was increased by STZ treatment in the hippocampus cell line, HT-22 cells. We evaluated whether Prx1 affects STZ-induced HT-22 cells using overexpression. Prx1 successfully protected the forms of STZ-induced AD-like pathology, such as neuronal apoptosis, synaptic loss, and tau phosphorylation. Moreover, Prx1 suppressed the STZ-induced increase of mitochondrial dysfunction and fragmentation by down-regulating Drp1 phosphorylation and mitochondrial location. Prx1 plays a role in an upstream signal pathway of Drp1 phosphorylation, cyclin-dependent kinase 5 (Cdk5) by inhibiting the STZ-induced conversion of p35 to p25. We found that STZ-induced of intracellular Ca2+ accumulation was an important modulator of AD-like pathology progression by regulating Ca2+-mediated Calpain activation, and Prx1 down-regulated STZ-induced intracellular Ca2+ accumulation and Ca2+-mediated Calpain activation. Finally, we identified that Prx1 antioxidant capacity affected Ca2+/Calpain/Cdk5-mediated AD-like pathology progress. Therefore, these findings demonstrated that Prx1 is a key factor in STZ-induced hippocampal neuronal death through inhibition of Ca2+/Calpain/Cdk5-mediated mitochondrial dysfunction by protecting against oxidative stress.


Asunto(s)
Enfermedad de Alzheimer , Calcio , Calpaína , Quinasa 5 Dependiente de la Ciclina , Hipocampo , Mitocondrias , Neuronas , Peroxirredoxinas , Estreptozocina , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/etiología , Quinasa 5 Dependiente de la Ciclina/metabolismo , Quinasa 5 Dependiente de la Ciclina/genética , Estreptozocina/toxicidad , Hipocampo/metabolismo , Hipocampo/patología , Neuronas/metabolismo , Neuronas/patología , Calpaína/metabolismo , Peroxirredoxinas/metabolismo , Peroxirredoxinas/genética , Mitocondrias/metabolismo , Ratones , Calcio/metabolismo , Línea Celular , Estrés Oxidativo , Apoptosis , Dinaminas/metabolismo , Dinaminas/genética , Fosforilación , Proteínas tau/metabolismo , Transducción de Señal
6.
Mol Brain ; 17(1): 43, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39003465

RESUMEN

Dorsal switch protein 1(DSP1), a mammalian homolog of HMGB1, is firstly identified as a dorsal co-repressor in 1994. DSP1 contains HMG-box domain and functions as a transcriptional regulator in Drosophila melanogaster. It plays a crucial role in embryonic development, particularly in dorsal-ventral patterning during early embryogenesis, through the regulation of gene expression. Moreover, DSP1 is implicated in various cellular processes, including cell fate determination and tissue differentiation, which are essential for embryonic development. While the function of DSP1 in embryonic development has been relatively well-studied, its role in the adult Drosophila brain remains less understood. In this study, we investigated the role of DSP1 in the brain by using neuronal-specific DSP1 overexpression flies. We observed that climbing ability and life span are decreased in DSP1-overexpressed flies. Furthermore, these flies demonstrated neuromuscular junction (NMJ) defect, reduced eye size and a decrease in tyrosine hydroxylase (TH)-positive neurons, indicating neuronal toxicity induced by DSP1 overexpression. Our data suggest that DSP1 overexpression leads to neuronal dysfunction and toxicity, positioning DSP1 as a potential therapeutic target for neurodegenerative diseases.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Degeneración Nerviosa , Unión Neuromuscular , Neuronas , Fenotipo , Animales , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Ojo/patología , Longevidad/genética , Degeneración Nerviosa/patología , Degeneración Nerviosa/genética , Unión Neuromuscular/metabolismo , Unión Neuromuscular/patología , Neuronas/metabolismo , Neuronas/patología , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Tirosina 3-Monooxigenasa/metabolismo , Tirosina 3-Monooxigenasa/genética
7.
Sensors (Basel) ; 24(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38610258

RESUMEN

In this paper, we propose an amount estimation method for food intake based on both color and depth images. Two pairs of color and depth images are captured pre- and post-meals. The pre- and post-meal color images are employed to detect food types and food existence regions using Mask R-CNN. The post-meal color image is spatially transformed to match the food region locations between the pre- and post-meal color images. The same transformation is also performed on the post-meal depth image. The pixel values of the post-meal depth image are compensated to reflect 3D position changes caused by the image transformation. In both the pre- and post-meal depth images, a space volume for each food region is calculated by dividing the space between the food surfaces and the camera into multiple tetrahedra. The food intake amounts are estimated as the difference in space volumes calculated from the pre- and post-meal depth images. From the simulation results, we verify that the proposed method estimates the food intake amount with an error of up to 2.2%.


Asunto(s)
Aprendizaje Profundo , Simulación por Computador , Alimentos , Periodo Posprandial , Ingestión de Alimentos
9.
Clin Endosc ; 57(1): 82-88, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38302248

RESUMEN

BACKGROUND/AIMS: Guide tube-assisted endoscopy for procedures that require repeated endoscopic access is safer and more effective than conventional endoscopy. However, its effectiveness has not been confirmed in animal studies. We assessed the usefulness of guide tube-assisted endoscopic procedures in an in vivo porcine model. METHODS: Five different guide tube-assisted endoscopic procedures were performed by experienced endoscopists on a pig weighing 32 kg. To evaluate the efficacy of these procedures, we compared the endoscopic approach time when a guide tube was used to that when it was not. Additional endoscopic procedures using a guide tube were performed, including multiple foreign body extractions, multiple polypectomies, and multiple submucosal dissections. To evaluate safety, we compared the insertion force into the proximal esophagus between the guide tube and conventional overtube methods. RESULTS: Using the endoscopic approach with a guide tube required a shorter average approach time to reach the three target lesions than when using the endoscopic approach without a guide tube (p<0.001). Compared to the conventional overtube method, the guide tube method produced a lower average resistance during insertion into the upper esophagus (p<0.001). CONCLUSION: Guide tube-assisted endoscopic procedures are effective and safe for repeated endoscopic access in an in vivo porcine model.

10.
Transl Cancer Res ; 12(9): 2405-2419, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37859730

RESUMEN

Background and Objective: Anastomotic leak (AL) remains a common and highly morbid complication after Ivor Lewis Esophagectomy. Leak is associated with increased morbidity, mortality, strictures and even cancer recurrence. Unfortunately, despite advances in surgical technique and perioperative care, the reported frequency of AL has remained largely unchanged. Methods: A PubMed search for all English-language articles that discuss Ivor Lewis esophagectomy, AL, risk factors, and outcomes was conducted from 1901 to 2023 prioritizing research from randomized trials that evaluated outcomes from patients undergoing esophagectomy. Key Content and Findings: This narrative review will discuss the prevailing literature on AL, risk factors and outcomes with a focus on its relationship to the Ivor Lewis esophagectomy (ILE). In particular, we emphasize that the gastric conduit, as commonly created for most esophagectomy procedures, is inherently vulnerable to ischemia. We will show trends in the literature that have contributed to the high rate of postoperative complications, with a focus on the AL. In addition, we propose that the traditional Ivor Lewis procedure itself is a risk factor for AL. We review a surgical alternative that increases blood supply of the conduit, and is associated with reduced leak, no strictures, and improved surgical outcomes. Conclusions: Multiple factors contribute to AL after esophagectomy; including several current surgical practices. We believe that some of them, especially the commonly accepted approach to the gastric conduit, can be modified to optimize tissue perfusion. With further investigation, we may reduce the incidence of short and long-term anastomotic complications and improve surgical outcomes.

11.
Life Sci ; 333: 122140, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37797684

RESUMEN

AIM: We aimed to determine the role of extracellular peroxiredoxin 1 (Prdx1) in the pathogenesis of bacterial infections and inflammatory bone disease. MATERIALS AND METHODS: We first investigated the role of Prdx1 using knockout mice. Next, we determined the role of extracellular Prdx1 in bacterial infections by using a neutralizing antibody against Prdx1. We finally investigated whether blockade of extracellular Prdx1 affected high- or low-grade inflammatory bone diseases using calvarial osteolysis, collagen-induced arthritis (CIA), and microgravity-induced bone loss in mouse models. KEY FINDINGS: The lack of Prdx1 increased susceptibility to infections by Listeria monocytogenes or Escherichia coli. Prdx1 is released into the serum upon E. coli infection, and blockade of extracellular Prdx1 confers significant protection against bacterial infections. Our data suggested that circulating Prdx1 is increased by the development of osteolytic disease, and that blockade of extracellular Prdx1 exerts therapeutic effects against high- and low-grade inflammatory bone loss. In addition, the release of Prdx1 under inflammatory osteolytic conditions partly depends on non-canonical TIR-domain-containing adapter-inducing interferon-ß (TRIF)-caspase-11-gasdemin D (GSDMD) inflammasome pathways. SIGNIFICANCE: Extracellular Prdx1 is involved in the development of bacterial infections and inflammatory bone disease. Thus, extracellular Prdx1 may represent a novel therapeutic target for bacterial infections or inflammatory osteolytic diseases.


Asunto(s)
Infecciones Bacterianas , Enfermedades Óseas , Ratones , Animales , Peroxirredoxinas/metabolismo , Escherichia coli/metabolismo , Caspasas
12.
ACS Appl Mater Interfaces ; 15(39): 45539-45548, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37713436

RESUMEN

Fluorescent dyes have garnered significant attention as theranostic platforms owing to their inherent characteristics. In this study, we present the discovery of Medical Fluorophore 33 (MF33), a novel and potent theranostic agent with a phenaleno-isoquinolinium salt structure that can serve as a cancer therapeutic strategy. The synthesis of MF33 is readily achievable through a simple Rh(III)-catalyzed reaction. Moreover, MF33 displayed strong fluorescence signals, excellent microsomal stability, and high biocompatibility in vivo. It induces significant apoptosis in cancer cells via the p53/p21/caspase-3 signaling pathway, leading to selective cytotoxicity in various cancer cells. In vivo fluorescence imaging with MF33 enabled the visualization of sentinel lymph nodes in living mice. Notably, repeated intraperitoneal administration of MF33 resulted in antitumor activity in mice with colorectal cancer. Collectively, our findings suggest that phenaleno-isoquinolinium salt-based MF33 is a viable theranostic agent for biomedical imaging and cancer treatment.


Asunto(s)
Colorantes Fluorescentes , Neoplasias , Animales , Ratones , Colorantes Fluorescentes/química , Medicina de Precisión , Estudios de Factibilidad , Neoplasias/terapia , Nanomedicina Teranóstica/métodos
13.
Pharmaceuticals (Basel) ; 16(8)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37631070

RESUMEN

A metastatic brain tumor is the most common type of malignancy in the central nervous system, which is one of the leading causes of death in patients with lung cancer. The purpose of this study is to evaluate the efficacy of a novel treatment for metastatic brain tumors with lung cancer using neural stem cells (NSCs), which encode rabbit carboxylesterase (rCE) and the secretion form of tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL). rCE and/or sTRAIL were transduced in immortalized human fetal NSCs, HB1.F3. The cytotoxic effects of the therapeutic cells on human lung cancer cells were evaluated in vitro with the ligands and decoy receptor expression for sTRAIL in the presence of CPT-11. Human NSCs encoding rCE (F3.CE and F3.CE.sTRAIL) significantly inhibited the growth of lung cancer cells in the presence of CPT-11 in vitro. Lung cancer cells were inoculated in immune-deficient mice, and therapeutic cells were transplanted systematically through intracardiac arterial injection and then treated with CPT-11. In resting state, DR4 expression in lung cancer cells and DcR1 in NSCs increased to 70% and 90% after CPT-11 addition, respectively. The volumes of the tumors in immune-deficient mice were reduced significantly in mice with F3.CE.sTRAIL transplantation and CPT-11 treatment. The survival was also significantly prolonged with treatment with F3.sTRAIL and F3.CE plus CPT-11 as well as F3.CE.sTRAIL plus CPT-11. NSCs transduced with rCE and sTRAIL genes showed a significant anti-cancer effect on brain metastatic lung cancer in vivo and in vitro, and the effect may be synergistic when rCE/CPT-11 and sTRAIL are combined. This stem-cell-based study using two therapeutic genes of different biological effects can be translatable to clinical application.

14.
Clin Endosc ; 56(5): 604-612, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37524564

RESUMEN

BACKGROUND/AIMS: We developed a new endoscopic submucosal dissection (ESD) simulator and evaluated its efficacy and realism for use training endoscopists. METHODS: An ESD simulator was constructed using polyvinyl alcohol hydrogel sheets and compared to a previous ESD simulator. Between March 1, 2020, and December 30, 2021, eight expert endoscopists from three different centers analyzed the procedure-related factors of the simulator. Five trainees performed gastric ESD exercises under the guidance of these experts. RESULTS: Although the two ESD simulators provided overall favorable outcomes in terms of ESD-related factors, the new simulator had several benefits, including better marking of the target lesion's limits (p<0.001) and overall handling (p<0.001). Trainees tested the usefulness of the new ESD simulator. The complete resection rate improved after 3 ESD training sessions (9 procedures), and the perforation rate decreased after 4 sessions (12 procedures). CONCLUSION: We have developed a new ESD simulator that can help beginners achieve a high level of technical experience before performing real-time ESD procedures in patients.

15.
Environ Res ; 233: 116438, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37331559

RESUMEN

Ecological macroalgal succession in glacier-free areas has remained at the pioneer seral stage despite six decades of glacial retreat at Marian Cove, King George Island, Antarctica. With the rapid melting of glaciers in the West Antarctic Peninsula owing to global warming, a massive amount of meltwater is flowing into the coast, creating marine environmental gradients such as turbidity, water temperature, and salinity. This study examined the spatial and vertical distributions (up to a depth of 25 m) of macroalgal assemblages from nine sites in Maxwell Bay and Marian Cove. The macroalgal assemblages were analyzed for six sites located 0.2, 0.8, 1.2, 2.2, 3.6, and 4.1 km away from the glacier, including three sites where the glacial retreat history of Marian Cove could be estimated. To investigate the effects of meltwater, differences in the coastal environment were analyzed based on data collected from five stations located 0.4, 0.9, 3.0, 4.0, and 5.0 km away from the glacier. The macroalgal assemblages and marine environment were divided into two groups-inside and outside the cove-based on the region 2-3 km away from the glacier, which has been ice-free since 1956 and shows significant differences. In the three sites near the glacier front, Palmaria decipiens was dominant, and three to four species were distributed, whereas in the two sites outside the cove, nine and 14 species appeared, respectively, similar to the assemblage of the other three sites in Maxwell Bay. Palmaria decipiens, a representative opportunistic pioneer species in Antarctica, is dominant because of its physiological adaptation despite the high turbidity and low water temperature of the glacier front. This study shows that macroalgal assemblages in Antarctic fjord-like coves respond to glacial retreat and are valuable in understanding the macroalgal succession in Antarctica.


Asunto(s)
Ecosistema , Estuarios , Regiones Antárticas , Agua , Cubierta de Hielo
16.
Toxicol Sci ; 194(2): 167-177, 2023 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-37261864

RESUMEN

In this study, we examined the mechanisms of cadmium exposure-induced endoplasmic reticulum (ER) stress response and apoptosis in spermatocytes. Responses to cadmium toxicity were investigated using spermatocytes overexpressing p50ATF6, ATF4, and spliced XBP1s, belonging to the 3 unfolded protein response pathways. The ER stress and apoptosis response to cadmium were most strongly stimulated through the activating transcription factor 6 (ATF6) pathway; in contrast, siRNA-induced inhibition of protein expression could reduce apoptosis under stressful conditions. An in vivo experiment using mice confirmed that upregulation of p50ATF6 in the testis increased apoptosis in response to cadmium exposure. Further, when confirming the correlation between ER stress and MAPK in cadmium toxicity, p38 MAPK phosphorylation was strongly regulated by p50ATF6; p-p38 also mediated the activity of p50ATF6. Overall, these findings suggest that modulating the activity of p38 MAPK and p50ATF6 in cadmium exposure-induced toxicity can be considered a potential strategy to treat infertility.


Asunto(s)
Factor de Transcripción Activador 6 , Cadmio , Masculino , Animales , Ratones , Cadmio/toxicidad , Factor de Transcripción Activador 6/metabolismo , Espermatocitos/metabolismo , Estrés del Retículo Endoplásmico , Apoptosis/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos
17.
J Neurosurg Case Lessons ; 5(21)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37218735

RESUMEN

BACKGROUND: The complexity of posterior fossa surgery can often lead to rare complications due to the anatomy involved. Vestibular schwannoma resection is a common pathology in the posterior fossa, often requiring surgical intervention. Given the proximity of this space to the brainstem, cranial nerve VII/VIII complex, and posterior inferior cerebellar artery (PICA), neurovascular complications are not infrequent. A rare vascular complication from this surgical approach is a lateral medullary infarction from injury to the lateral medullary segment of the proximal PICA, leading to central hypoventilation syndrome (CHS). OBSERVATIONS: This report presents a unique case of a 51-year-old man who underwent a retrosigmoid craniectomy for resection of a vestibular schwannoma. Following surgery, the patient was unable to be weaned off the ventilator and was noted to become apneic while he slept, a clinical picture consistent with Ondine's curse. LESSONS: This report discusses the anatomical considerations of this surgical corridor leading to this complication and the management of a patient with acquired Ondine's curse and reviews the scarce literature on this uncommon cause of acquired CHS.

18.
Sensors (Basel) ; 23(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37112458

RESUMEN

Airflow in a multi-zone building can be a major cause of pollutant transfer, excessive energy consumption, and occupants discomfort. The key to monitoring airflows and mitigating related problems is to obtain a comprehensive understanding of pressure relationships within the buildings. This study proposes a visualization method for representing pressure distribution within a multi-zone building by using a novel pressure-sensing system. The system consists of a Master device and a couple of Slave devices that are connected with each other by a wireless sensor network. A 4-story office building and a 49-story residential building were installed with the system to detect pressure variations. The spatial and numerical mapping relationships of each zone were further determined through grid-forming and coordinate-establishing processes for the building floor plan. Lastly, 2D and 3D visualized pressure mappings of each floor were generated, illustrating the pressure difference and spatial relationship between adjacent zones. It is expected that the pressure mappings derived from this study will allow building operators to intuitively perceive the pressure variations and the spatial layouts of the zones. These mappings also make it possible for operators to diagnose the differences in pressure conditions between adjacent zones and plan a control scheme for the HVAC system more efficiently.

19.
Biosci Biotechnol Biochem ; 87(7): 696-706, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37024271

RESUMEN

Obesity is caused by the accumulation of excess lipids due to an energy imbalance. Differentiation of pre-adipocytes induces abnormal lipid accumulation, and reactive oxygen species (ROS) generated in this process promote the differentiation of pre-adipocytes through mitogen-activated protein kinase (MAPK) signaling. Peroxiredoxin (Prx) is a potent antioxidant enzyme, and peroxiredoxin 5 (Prx5), which is mainly expressed in cytosol and mitochondria, inhibits adipogenesis by regulating ROS levels. Based on previous findings, the present study was performed to investigate whether cytosolic Prx5 (CytPrx5) or mitochondrial Prx5 (MtPrx5) has a greater effect on the inhibition of adipogenesis. In this study, MtPrx5 decreased insulin-mediated ROS levels to reduce adipogenic gene expression and lipid accumulation more effectively than CytPrx5. In addition, we found that p38 MAPK mainly participates in adipogenesis. Furthermore, we verified that MtPrx5 overexpression suppressed the phosphorylation of p38 during adipogenesis. Thus, we suggest that MtPrx5 inhibits insulin-induced adipogenesis more effectively than CytPrx5.


Asunto(s)
Adipogénesis , Insulina , Proteínas Quinasas p38 Activadas por Mitógenos , Animales , Ratones , Células 3T3-L1 , Diferenciación Celular , Insulina/metabolismo , Lípidos/farmacología , Mitocondrias/metabolismo , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Peroxirredoxinas/farmacología , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
20.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36678621

RESUMEN

The main cause of erectile dysfunction (ED) is the damage in penile cavernous endothelial cells (EC). Murine primary ECs have a limited growth potential, and the easy availability of murine ECs will facilitate the study of cavernous endothelial dysfunction in rats. This study was performed to establish immortalized rat penile cavernous ECs (rEC) and investigate how they could repair erectile dysfunction in rats with cavernous nerve injury (CNI). rEC was isolated enzymatically by collagenase digestion and were cultured. An amphotropic replication-incompetent retroviral vector encoding v-myc oncogene was used to transfect rEC for immortalization (vREC). Morphological and immunohistochemical properties of vREC were examined. Eight-week-old male Sprague-Dawley rats were divided into three groups of five rats each, including group 1 = sham operation, group 2 = bilateral CN injury, group 3 = vREC (1 × 106 cells) treatment after CNI. Erectile response was assessed at 2, 4 weeks after transplantation of vREC., Penile tissue were harvested at 4 weeks after transplantation and immune−histochemical examination was performed. vREC showed the expression of CD31, vWF, cell type-specific markers for EC by RT-PCR and flowcytometry. At 2, 4 weeks after transplantation, rats with CNI had significantly lower erectile function than control group (p < 0.05). The group transplanted with vREC showed higher erectile function than the group without vRECs (p < 0.05). vREC was established and repaired erectile dysfunction in rats with CNI. This cell line may be useful for studying mechanisms and drug screening of erectile dysfunction of rats.

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