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1.
Nat Immunol ; 24(2): 225-238, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36624165

RESUMEN

Skin is exposed to various environmental assaults and undergoes morphological changes immediately after birth. Proper localization and function of immune cells in the skin is crucial for protection and establishment of skin tissue homeostasis. Here we report the discovery of a developmentally programmed process that directs preferential localization of invariant natural killer T (iNKT) cells to the skin for early local homeostatic regulation. We show that iNKT cells are programmed predominantly with a CCR10+ skin-homing phenotype during thymic development in infant and young mice. Early skin localization of iNKT cells is critical for proper commensal bacterial colonization and tissue development. Mechanistically, skin iNKT cells provide a local source of transferrin that regulates iron metabolism in hair follicle progenitor cells and helps hair follicle development. These findings provide molecular insights into the establishment and physiological functions of iNKT cells in the skin during early life.


Asunto(s)
Células T Asesinas Naturales , Ratones , Animales , Piel , Homeostasis , Ratones Endogámicos C57BL , Ratones Noqueados
2.
Immunity ; 55(10): 1891-1908.e12, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36044899

RESUMEN

Demodex mites are commensal parasites of hair follicles (HFs). Normally asymptomatic, inflammatory outgrowth of mites can accompany malnutrition, immune dysfunction, and aging, but mechanisms restricting Demodex outgrowth are not defined. Here, we show that control of mite HF colonization in mice required group 2 innate lymphoid cells (ILC2s), interleukin-13 (IL-13), and its receptor, IL-4Ra-IL-13Ra1. HF-associated ILC2s elaborated IL-13 that attenuated HFs and epithelial proliferation at anagen onset; in their absence, Demodex colonization led to increased epithelial proliferation and replacement of gene programs for repair by aberrant inflammation, leading to the loss of barrier function and HF exhaustion. Humans with rhinophymatous acne rosacea, an inflammatory condition associated with Demodex, had increased HF inflammation with decreased type 2 cytokines, consistent with the inverse relationship seen in mice. Our studies uncover a key role for skin ILC2s and IL-13, which comprise an immune checkpoint that sustains cutaneous integrity and restricts pathologic infestation by colonizing HF mites.


Asunto(s)
Infestaciones por Ácaros , Ácaros , Animales , Citocinas , Folículo Piloso/patología , Humanos , Inmunidad Innata , Inflamación , Interleucina-13 , Linfocitos/patología , Ratones , Infestaciones por Ácaros/complicaciones , Infestaciones por Ácaros/parasitología , Infestaciones por Ácaros/patología , Simbiosis
3.
Childs Nerv Syst ; 40(4): 1207-1212, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38147105

RESUMEN

BACKGROUND: Traumatic brain injury (TBI) is a significant cause of morbidity and mortality in pediatric patients, leading to long-term physical, cognitive, and psychological impairments. Blood lactate and fibrinogen levels have emerged as potential biomarkers associated with tissue hypoperfusion and coagulation dysfunction, respectively. However, limited research has specifically focused on the significance of these biomarkers in pediatric TBI. This study aimed to investigate the clinical significance of blood lactate and fibrinogen levels upon admission in pediatric patients with traumatic brain injury. METHODS: The medical records of 80 children with a traumatic brain injury who were admitted from January 2017 to January 2021 were retrospectively analyzed. The two groups were compared according to whether the blood lactate in the admission arterial blood gas increased and the fibrinogen content in the coagulation function decreased. The clinical data of the children in the two groups were different, and then they were divided into a good prognosis group and a poor prognosis group according to the GOS prognostic score, and the differences in the clinical indicators of the two groups were compared. RESULTS: Among the 80 patients, 33 had elevated blood lactate levels, 34 had decreased fibrinogen levels, and 29 had an unfavorable outcome (GOS < 4). Compared to the normal blood lactate group, there were no statistically significant differences in age, sex ratio, or platelet count in the elevated blood lactate group (P > 0.05). However, the elevated blood lactate group had lower Glasgow Coma Scale (GCS) scores upon admission, higher blood lactate levels, lower fibrinogen levels, longer hospital stay, lower GOS scores, and a higher proportion of GOS < 4 (P < 0.05). Compared to the normal fibrinogen group, there were no statistically significant differences in age, sex ratio, or platelet count in the decreased fibrinogen group (P > 0.05). However, the decreased fibrinogen group had lower GCS scores upon admission, higher blood lactate levels, lower fibrinogen levels, longer hospital stays, lower GOS scores, and a higher proportion of GOS < 4 (P < 0.05). Compared to the favorable outcome group, there were no statistically significant differences in age, sex ratio, or platelet count in the unfavorable outcome group (P > 0.05). However, the unfavorable outcome group had lower GCS scores upon admission, higher blood lactate levels, lower fibrinogen levels, longer hospital stays, a higher incidence of pulmonary infection, a higher incidence of stress ulcers, and lower GOS scores (P < 0.05). CONCLUSION: The levels of blood lactate and fibrinogen may represent the severity of children with traumatic brain injury and may be risk factors for poor prognosis of children with traumatic brain injury.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Fibrinógeno , Humanos , Niño , Pronóstico , Estudios Retrospectivos , Lesiones Traumáticas del Encéfalo/complicaciones , Escala de Coma de Glasgow , Biomarcadores , Lactatos
4.
Neurosurg Rev ; 47(1): 331, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008189

RESUMEN

To determine a rapid and accurate method for locating the keypoint and "keyhole" in the suboccipital retrosigmoid keyhole approach. (1) Twelve adult skull specimens were selected to locate the anatomical landmarks on the external surface of the skull.The line between the infraorbital margin and superior margin of the external acoustic meatus was named the baseline. A coordinate system was established using the baseline and its perpendicular line through the top point of diagastric groove.The perpendicular distance (x), and the horizontal distance (y) between the central point of the "keyhole" and the top point of the digastric groove in that coordinate system were measured. The method was applied to fresh cadaveric specimens and 53 clinical cases to evaluate its application value. (1) x and y were 14.20 ± 2.63 mm and 6.54 ± 1.83 mm, respectively (left) and 14.95 ± 2.53 mm and 6.65 ± 1.61 mm, respectively (right). There was no significant difference between the left and right sides of the skull (P > 0.05). (2) The operative area was satisfactorily exposed in the fresh cadaveric specimens, and no venous sinus injury was observed. (3) In clinical practice, drilling did not cause injury to venous sinuses, the mean diameter of the bone windows was 2.0-2.5 cm, the mean craniotomy time was 26.01 ± 3.46 min, and the transverse and sigmoid sinuses of 47 patients were well-exposed. We propose a "one point, two lines, and two distances" for "keyhole" localization theory, that is we use the baseline between the infraorbital margin and superior margin of the external acoustic meatus and the perpendicular line to the baseline through the top point of the digastric groove to establish a coordinate system. And the drilling point was 14.0 mm above and 6.5 mm behind the top point of the digastric groove in the coordinate system.


Asunto(s)
Cadáver , Senos Craneales , Craneotomía , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Senos Craneales/anatomía & histología , Senos Craneales/cirugía , Craneotomía/métodos , Procedimientos Neuroquirúrgicos/métodos , Anciano , Adulto Joven , Senos Transversos/anatomía & histología , Senos Transversos/cirugía , Cráneo/anatomía & histología , Cráneo/cirugía
5.
J Craniofac Surg ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38534161

RESUMEN

OBJECTIVE: To review our single-institution experience in the surgical management of complex skull base tumors using multimodal image fusion technology. METHODS: From October 2019 to January 2022, 7 cases of complex skull base tumors that performed preoperative multimodal image fusion in Zhuhai People's Hospital neurosurgery department were involved in this study. The image data were uploaded to the GE AW workstation. Corresponding image sequences were opened in the workstation to complete registration fusion and 3D reconstruction. We retrospectively reviewed the clinical and imaging data, and surgical strategy, respectively. RESULTS: one case of recurrent C2 schwannoma, 1 case of recurrent spindle cell tumor of the left cranio-orbital communication, 1 case of lobular malignant tumor of the left infratemporal fossa, 1 case of central giant cell repairing granuloma, 1 case of mesenchymal malignant tumor in left pharyngeal process, 1 case of meningioma in jugular foramen, and 1 case of hemangioblastoma with vascular malformation in fourth ventricular. All cases underwent preoperative multimodal image fusion for the surgical plan and all cases had gross total resection. Except for one case of mesenchymal malignant tumor in left pharyngeal process that had dysphagia and one case of hemangioblastoma that had discoordination, others cases were without postoperative complication. CONCLUSIONS: Preoperative multimodal image fusion and surgical approach simulation benefit complex skull base tumor surgical treatment. Individually multiple image assessment of complex skull base tumors to determine the specific surgical strategy is more rational and should be recommended (Supplemental Digital Content 1, Supplementary Video, http://links.lww.com/SCS/F936).

6.
Opt Express ; 31(5): 7994-8004, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859918

RESUMEN

We propose a scheme to realize robust optical entanglement in cavity optomagnonics, where two optical whispering gallery modes (WGMs) couple to a magnon mode in a yttrium iron garnet (YIG) sphere. The beam-splitter-like and two-mode squeezing magnon-photon interactions can be realized simultaneously when the two optical WGMs are driven by external fields. Entanglement between the two optical modes is then generated via their coupling with magnons. By exploiting the destructive quantum interference between the bright modes of the interface, the effects of initial thermal occupations of magnons can be eliminated. Moreover, the excitation of the Bogoliubov dark mode is capable of protecting the optical entanglement from thermal heating effects. Therefore, the generated optical entanglement is robust against thermal noise and the requirement of cooling the magnon mode is relaxed. Our scheme may find applications in the study of magnon-based quantum information processing.

7.
J Org Chem ; 88(18): 13125-13134, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37616489

RESUMEN

A new one-pot synthesis of imidazo[1,2-a]pyridine-fused 1,3-benzodiazepine derivatives via a sequential GBB-3CR/Pd(II)-catalyzed azide-isocyanide coupling/cyclization process was developed. The Groebke-Blackburn-Bienaymé three-component reactions (GBB-3CR) of 2-aminopyridine, 2-azidobenzaldehydes, and isocyanides in the presence of a catalytic amount of p-toluenesulfonic acid gave azide intermediates without separation. The reaction was followed by using another molecule of isocyanides to produce imidazo[1,2-a]pyridine-fused 1,3-benzodiazepine derivatives in good yields by the Pd(II)-catalyzed azide-isocyanide coupling/cyclization reaction. The synthetic approach produces novel nitrogen-fused polycyclic heterocycles under mild reaction conditions. The preliminary biological evaluation demonstrated that compound 6a inhibited glioma cells efficiently, suggesting potentially broad applications of the approach for synthesis and medicinal chemistry.

8.
Arch Orthop Trauma Surg ; 143(9): 5657-5670, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37079105

RESUMEN

INTRODUCTION: This meta-analysis aimed to compare the differences in postoperative efficacy between oblique lumbar interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in the treatment of lumbar degenerative diseases. MATERIALS AND METHODS: Strictly based on the search strategy, we searched the published papers on OLIF and TLIF for the treatment of lumbar degenerative diseases in PubMed, Embase, CINAHL, and Cochrane Library. A total of 607 related papers were retrieved, and 15 articles were finally included. The quality of the papers was evaluated according to the Cochrane systematic review methodology, and the data were extracted and meta-analyzed using Review manager 5.4 software. RESULTS: Through comparison, it was found that in the treatment of lumbar degenerative diseases, the OLIF group had certain advantages over the TLIF group in terms of intraoperative blood loss, hospital stay, visual analog scale (VAS) for leg pain (VAS-LP), Oswestry disability index (ODI), disc height (DH), foraminal height (FH), fused segmental lordosis (FSL), and cage height, and the differences were statistically significant. The results were similar in terms of surgery time, complications, fusion rate, VAS for back pain (VAS-BP) and various sagittal imaging indicators, and there was no significant difference. CONCLUSIONS: OLIF and TLIF can relieve low back pain symptoms in the treatment of lumbar degenerative diseases, but OLIF has certain advantages in terms of ODI and VAS-LP. In addition, OLIF has the advantages of minor intraoperative trauma and quick postoperative recovery.


Asunto(s)
Vértebras Lumbares , Fusión Vertebral , Humanos , Resultado del Tratamiento , Estudios Retrospectivos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Región Lumbosacra , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos
9.
Opt Express ; 30(7): 10306-10316, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35473001

RESUMEN

The generation and manipulation of highly pure and strongly entangled steady state in a quantum system are vital tasks in the standard continuous-variable teleportation protocol. Especially, the manipulation implemented in integrated devices is even more crucial in practical quantum information applications. Here we propose an effective approach for creating steady-state entanglement between two microwave fields in a four-mode hybrid cavity optomechanical system. The entanglement can be achieved by combining the processes of three beam-splitter interactions and two parametric-amplifier interactions. Due to the dissipation-driven and cavity cooling processes, the entanglement obtained can go far beyond the entanglement limit based on coherent parametric coupling. Moreover, our proposal allows the engineered bath to cool both Bogoliubov modes almost simultaneously. In this way, a highly pure and strongly entangled steady state of two microwave modes is obtained. Our finding may be significant for using the hybrid opto-electro-mechanical system fabricated on chips in various quantum tasks, where the strong and pure entanglement is an important resource.

10.
Opt Lett ; 47(3): 469-472, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35103653

RESUMEN

The beam scanner is a predominant part in the light detection and ranging (LiDAR) system to achieve three-dimensional (3D) imaging. The solid-state beam-steering device has emerged as a promising candidate technology for a beam scanner with the advantages of robustness, stability, and high scanning speed. Here we propose a frequency modulated continuous wave (FMCW) LiDAR system with an in-fiber solid-state beam scanner. A 45° tilted fiber grating (TFG) is first employed to achieve in-fiber solid-state spectral scanning in the LiDAR system. A maximum output efficiency of 93.7% is achieved with proper polarization control. A single-mode fiber is then used to fabricate a 2-cm 45° TFG, which significantly reduces the size and the cost of the beam scanner in the LiDAR system. We experimentally realize 3D imaging of targets placed at a distance of 1.2 m based on our proposed LiDAR system. In addition, the system can achieve a detection distance of 6 m with a ranging precision of 24 mm.

11.
Molecules ; 27(17)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36080331

RESUMEN

Endophytes and their elicitors can all be utilized in regulating crop biochemical qualities. However, living endophytes and their derived elicitors are always applied separately; little is known about the similarities and differences of their effects. To increase the efficiency of this system when applied in practice, the present work profiled simultaneously the metabolomes in grape cells exposed to endophytic fungi (EF) and their corresponding fungal extracts (CFE). As expected, grape cells exposed separately to different fungi, or to different fungi derived extracts, each exhibited different modifications of metabolite patterns. The metabolic profiles of certain EF- and CFE-exposed grape cells were also differently influenced to certain degrees, owing to the presence of differentially responding metabolites (DRMs). However, the detected majority proportions of coordinately responding metabolites (CRMs) in both the EF- and the CFE-exposed grape cells, as well as the significantly influenced metabolites (SIMs) which are specific to certain fungal strains, clearly indicate coordinative changes in metabolites in grape cells exposed to EF and CFEs. The coordinative changes in metabolites in EF- and CFE-treated grape cells appeared to be fungal strain-dependent. Notably, several of those fungal strain-specific CRMs and DRMs are metabolites and belong to amino acids, lipids, organic acids, phenolic acids, flavonoids, and others, which are major contributors to the biochemistry and sensory qualities of grapes and wines. This research clarifies the detailed responses of metabolites in grape cells exposed to EF and CFEs. It also demonstrates how endophytes can be selectively used in the form of extracts to produce functions as CRMs of the living fungus with increased eco-safety, or separately applied to the living microbes or elicitors to emphasize those effects related to their specifically initiated SIMs and DRMs.


Asunto(s)
Vitis , Vino , Endófitos/metabolismo , Hongos/metabolismo , Metaboloma , Vitis/metabolismo
12.
Biochem Biophys Res Commun ; 541: 1-7, 2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33450580

RESUMEN

BACKGROUND: Chronic hypoxia plays an important role in the initiation and progression of chronic renal disease. The pathogenic role of chronic hypoxia in tubulointerstitial injury has been investigated widely, but little is known about acute hypoxia implications in glomerular damage. In this study, we investigated the effect of chronic hypoxia on transient receptor potential cation channel 6 (TRPC6) and the underlying mechanism in cultured human podocytes. METHODS: Fluo-3 was used as a calcium indicator of the OAG-induced receptor operated calcium entry (ROCE) and basal [Ca2+]i levels were monitored using laser scanning confocal microscope after exposure of cells to chronic hypoxia. 2-aminoethoxydiphenylborane (2-APB), a pharmacological blocker of TRPCs channels, was used to determine the role of TRPC6 in podocytes under chronic hypoxia. The mRNA expression and protein levels of TRPC6 were determined using Real-time RT-PCR and Western Blotting under normoxic and chronic hypoxic conditions. Actin arrangement was analyzed by confocal microscopy using phalloidin staining of F-actin in podocytes. RESULTS: Cytosolic free Ca2+ was increased by hypoxia or the treatment of TRPC6 agonist OAG under normoxic conditions. The increase of intracellular Ca2+ induced by hypoxia was time- and dose-dependent, which can be inhibited by 2-APB, demonstrating that the changes of intracellular Ca2+ induced by OAG depend on the activation of TRPC6. Further study showed that the TRPC6 expression levels were significantly increased by hypoxia, which were inhibited by the HIF1α inhibitor in podocytes. Similarly, the increase of intracellular Ca2+ induced by hypoxia was decreased when the podocytes were incubated with HIF1α inhibitor. We also found that F-actin was ruptured by hypoxia in podocytes, showing cytoskeleton reorganization. CONCLUSIONS: TRPC6 mRNA and protein expression levels were significantly increased in podocytes under hypoxia, which may result in the increase of intracellular Ca2+. This alternation of TRPC6 may be relevant to the modulation of HIF1α. Hypoxia in podocytes can result in cytoskeleton reorganization, which further leads to podocytes injury and disfunction.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hipoxia/genética , Hipoxia/metabolismo , Podocitos/metabolismo , Podocitos/patología , Canal Catiónico TRPC6/genética , Canal Catiónico TRPC6/metabolismo , Actinas/metabolismo , Compuestos de Boro/farmacología , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Línea Celular , Citoesqueleto/metabolismo , Diglicéridos/farmacología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Oxígeno/metabolismo , Oxígeno/farmacología , Podocitos/efectos de los fármacos , ARN Mensajero/análisis , ARN Mensajero/genética , Factores de Tiempo
13.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-34209973

RESUMEN

In maize, the ear shank is a short branch that connects the ear to the stalk. The length of the ear shank mainly affects the transportation of photosynthetic products to the ear, and also influences the dehydration of the grain by adjusting the tightness of the husks. However, the molecular mechanisms of maize shank elongation have rarely been described. It has been reported that the maize ear shank length is a quantitative trait, but its genetic basis is still unclear. In this study, RNA-seq was performed to explore the transcriptional dynamics and determine the key genes involved in maize shank elongation at four different developmental stages. A total of 8145 differentially expressed genes (DEGs) were identified, including 729 transcription factors (TFs). Some important genes which participate in shank elongation were detected via function annotation and temporal expression pattern analyses, including genes related to signal transduction hormones (auxin, brassinosteroids, gibberellin, etc.), xyloglucan and xyloglucan xyloglucosyl transferase, and transcription factor families. The results provide insights into the genetic architecture of maize ear shanks and developing new varieties with ideal ear shank lengths, enabling adjustments for mechanized harvesting in the future.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes , Zea mays/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ontología de Genes , Fenotipo , Proteínas de Plantas/genética , Sitios de Carácter Cuantitativo , Factores de Transcripción , Zea mays/genética
14.
Medicina (Kaunas) ; 57(9)2021 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-34577855

RESUMEN

Background and Objectives: Thymomas are associated with a high frequency of paraneoplastic manifestations. Paraneoplastic syndrome (PNS) with thymoma presents a challenge to clinicians because of the need to decipher the association between the presenting symptoms and the underlying tumor. The condition most commonly noted in patients with PNS with thymoma is myasthenia gravis. Other common autoimmune diseases that may present as PNS include systemic lupus erythematosus, pure red cell aplasia, and Good syndrome. Seventy-six percent of patients with PNS-associated thymoma experience resolution of PNS after curing thymoma. Materials and Methods: A 37-year-old man with a two-month fever accompanied by polyarthritis accidently found thymoma after contrast computed tomography scans of his chest. He accepted Video assisted thoracoscopic surgery with resection of thymoma. Results: Fever and polyarthritis resolved after operation but recurred in five days due to cytomegalovirus viremia, which might be predisposed by previous antibiotics treatment before the diagnosis of thymoma. Conclusion: Patients with a thymoma also have a high frequency of PNS, and the most frequent condition found in patients with PNS-associated thymoma is myasthenia gravis. Fever with polyarthritis has been rarely reported as a symptom of PNS-associated thymoma. Here we reported an unusual case of PNS mimicking reactive arthritis with thymoma, as diagnosed based on the patient's clinical progression, imaging examination, and laboratory tests. The patient died of his comorbidities, and his death may have been related to long-term antibiotic use and consequent intestinal dysbiosis. This challenging case may help to inform clinicians of the need for detailed work-up of fever with unknown origin in the presence of chronic polyarthritis to prevent the overdiagnosis of inflammatory arthritis or rheumatic disease and avoid further comorbidities. Detailed work-up should include the patient's history of infections, inflammation, and malignant or nonmalignant tumors.


Asunto(s)
Artritis Reactiva , Miastenia Gravis , Síndromes Paraneoplásicos , Timoma , Neoplasias del Timo , Adulto , Humanos , Masculino , Miastenia Gravis/complicaciones , Miastenia Gravis/diagnóstico , Recurrencia Local de Neoplasia , Síndromes Paraneoplásicos/diagnóstico , Timoma/complicaciones , Timoma/diagnóstico , Neoplasias del Timo/complicaciones , Neoplasias del Timo/diagnóstico
15.
Blood ; 132(24): 2580-2593, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30322871

RESUMEN

Anemic stress induces a physiological response that includes the rapid production of new erythrocytes. This process is referred to as stress erythropoiesis. It is best understood in the mouse where it is extramedullary and utilizes signals and progenitor cells that are distinct from bone marrow steady-state erythropoiesis. The development of stress erythroid progenitors occurs in close association with the splenic stress erythropoiesis niche. In particular, macrophages in the niche are required for proper stress erythropoiesis. Here we show that the expansion of the niche occurs in concert with the proliferation and differentiation of stress erythroid progenitors. Using lineage tracing analysis in 2 models of anemic stress, we show that the expansion of the splenic niche is due to the recruitment of monocytes into the spleen, which develop into macrophages that form erythroblastic islands. The influx in monocytes into the spleen depends in part on Ccr2-dependent signaling mediated by Ccl2 and other ligands expressed by spleen resident red pulp macrophages. Overall, these data demonstrate the dynamic nature of the spleen niche, which rapidly expands in concert with the stress erythroid progenitors to coordinate the production of new erythrocytes in response to anemic stress.


Asunto(s)
Anemia/metabolismo , Eritropoyesis , Macrófagos/metabolismo , Monocitos/metabolismo , Transducción de Señal , Estrés Fisiológico , Anemia/genética , Anemia/patología , Animales , Quimiocina CCL2/genética , Modelos Animales de Enfermedad , Macrófagos/patología , Ratones , Ratones Noqueados , Monocitos/patología
16.
Blood ; 131(23): 2568-2580, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29615406

RESUMEN

Micronutrient selenium (Se) plays a key role in redox regulation through its incorporation into selenoproteins as the 21st amino acid selenocysteine (Sec). Because Se deficiency appears to be a cofactor in the anemia associated with chronic inflammatory diseases, we reasoned that selenoproteins may contribute to erythropoietic recovery from anemia, referred to as stress erythropoiesis. Here, we report that loss of selenoproteins through Se deficiency or by mutation of the Sec tRNA (tRNA[Sec]) gene (Trsp) severely impairs stress erythropoiesis at 2 stages. Early stress erythroid progenitors failed to expand and properly differentiate into burst-forming unit-erythroid cells , whereas late-stage erythroid progenitors exhibited a maturation defect that affected the transition of proerythroblasts to basophilic erythroblasts. These defects were, in part, a result of the loss of selenoprotein W (SelenoW), whose expression was reduced at both transcript and protein levels in Se-deficient erythroblasts. Mutation of SelenoW in the bone marrow cells significantly decreased the expansion of stress burst-forming unit-erythroid cell colonies, which recapitulated the phenotypes induced by Se deficiency or mutation of Trsp Similarly, mutation of SelenoW in murine erythroblast (G1E) cell line led to defects in terminal differentiation. In addition to the erythroid defects, the spleens of Se-deficient mice contained fewer red pulp macrophages and exhibited impaired development of erythroblastic island macrophages, which make up the niche supporting erythroblast development. Taken together, these data reveal a critical role of selenoproteins in the expansion and development of stress erythroid progenitors, as well as the erythroid niche during acute anemia recovery.


Asunto(s)
Anemia/metabolismo , Células Precursoras Eritroides/citología , Eritropoyesis , Selenio/deficiencia , Selenoproteínas/metabolismo , Anemia/genética , Animales , Regulación hacia Abajo , Eritroblastos/citología , Eritroblastos/metabolismo , Células Precursoras Eritroides/metabolismo , Ratones Endogámicos C57BL , Mutación , Selenio/metabolismo , Selenoproteína W/genética , Selenoproteína W/metabolismo , Selenoproteínas/genética , Bazo/citología , Bazo/metabolismo
17.
Hu Li Za Zhi ; 67(5): 6-11, 2020 Oct.
Artículo en Zh | MEDLINE | ID: mdl-32978760

RESUMEN

In this article, technologies that have been widely adopted and used in the field of allied health education in recent years are identified and introduced. These technologies may be distinguished based on education content and approach into the following three categories: online-offline digital education, which uses massive open online courses, CD-ROM, and similar learning tools; mobile learning, which uses mobile phones, tablets, and other devices to connect to the Internet of things; and digital simulation education, which uses virtual reality, virtual patient simulation, serious gaming, and gamification. Preliminary positive findings regarding the effectiveness of using the above technologies have been reported in the literature. Therefore, to better understand the impact of new technology, it is recommended that relevant medical/nursing educators should continue introducing practical courses to evaluate their impact on learning. However, funding limitations and the declining birthrate / population aging are two key threats to education that remain to be effectively addressed and overcome.


Asunto(s)
Técnicos Medios en Salud/educación , Comunicación , Educación en Salud/organización & administración , Tecnología de la Información , Humanos
18.
Inorg Chem ; 58(23): 15880-15888, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31718174

RESUMEN

Graphitic carbon nitride (g-C3N4)-based materials have attracted interdisciplinary attention from many fields. However, their crystal structures have not yet been described well. Poly(triazine imide)/LiCl (PTI/LiCl) of good crystallinity synthesized from salt melts enables a confident structural solution for a better understanding of g-C3N4-based materials. In this study, we synthesize PTI/LiCl of high crystallinity in air without byproducts and confirm the orthorhombic feature, which is not observed in powder X-ray diffraction (PXRD) patterns at room temperature, by employing low-temperature synchrotron PXRD. Together with spectroscopic techniques (X-ray photoelectron spectroscopy, solid-state nuclear magnetic resonance, and Fourier-transform infrared/Raman), the orthorhombic structure (space group Cmc21, No. 36) was determined and found to be a superstructure of the previously reported hexagonal structure, as confirmed by electron diffraction. The temperature-dependent synchrotron PXRD data also reveal a highly anisotropic expansion. This work also shows the much higher activity of PTI/LiCl than of g-C3N4 for the photocatalytic degradation of methyl orange under ultraviolet irradiation, especially so for PTI/LiCl with a densely packed (001) plane. This study demonstrates the structural complexity of the g-C3N4 class of materials and illustrates how their temperature-dependent anisotropies facilitate the discovery of the structural features in resolving the structure of g-C3N4-related materials and their structure-property relationship.

19.
Opt Express ; 26(11): 13783-13799, 2018 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-29877426

RESUMEN

We systematically study the influence of amplitude modulation on the steady-state bosonic squeezing and entanglement in a dissipative three-mode optomechanical system, where a vibrational mode of the membrane is coupled to the left and right cavity modes via the radiation pressure. Numerical simulation results show that the steady-state bosonic squeezing and entanglement can be significantly enhanced by periodically modulated external laser driving either or both ends of the cavity. Remarkably, the fact that as long as one periodically modulated external laser driving either end of the cavities is sufficient to enhance the squeezing and entanglement is convenient for actual experiment, whose cost is that required modulation period number for achieving system stability is more. In addition, we numerically confirm the analytical prediction for optimal modulation frequency and discuss the corresponding physical mechanism.

20.
Cell Physiol Biochem ; 43(5): 1777-1789, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29050010

RESUMEN

BACKGROUND/AIMS: Recent studies provided compelling evidence that stimulation of the calcium sensing receptor (CaSR) exerts direct renoprotective action at the glomerular podocyte level. This protective action may be attributed to the RhoA-dependent stabilization of the actin cytoskeleton. However, the underlying mechanisms remain unclear. METHODS: In the present study, an immortalized human podocyte cell line was used. Fluo-3 fluorescence was utilized to determine intracellular Ca2+ concentration ([Ca2+]i), and western blotting was used to measure canonical transient receptor potential 6 (TRPC6) protein expression and RhoA activity. Stress fibers were detected by FITC-phalloidin. RESULTS: Activating CaSR with a high extracellular Ca2+ concentration ([Ca2+]o) or R-568 (a type II CaSR agonist) induces an increase in the [Ca2+]i in a dose-dependent manner. This increase in [Ca2+]i is phospholipase C (PLC)-dependent and is smaller in the absence of extracellular Ca2+ than in the presence of 0.5 mM [Ca2+]o. The CaSR activation-induced [Ca2+]i increase is attenuated by the pharmacological blockage of TRPC6 channels or siRNA targeting TRPC6. These data suggest that TRPC6 is involved in CaSR activation-induced Ca2+ influx. Consistent with a previous study, CaSR stimulation results in an increase in RhoA activity. However, the knockdown of TRPC6 significantly abolished the RhoA activity increase induced by CaSR stimulation, suggesting that TRPC6-dependent Ca2+ entry is required for RhoA activation. The activated RhoA is involved in the formation of stress fibers and focal adhesions in response to CaSR stimulation because siRNA targeting RhoA attenuated the increase in the stress fiber mediated by CaSR stimulation. Moreover, this effect of CaSR activation on the formation of stress fibers is also abolished by the knockdown of TRPC6. CONCLUSION: TRPC6 is involved in the regulation of stress fiber formation and focal adhesions via the RhoA pathway in response to CaSR activation. This may explain the direct protective action of CaSR agonists.


Asunto(s)
Calcio/metabolismo , Glomérulos Renales/citología , Podocitos/metabolismo , Receptores Sensibles al Calcio/metabolismo , Canal Catiónico TRPC6/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Western Blotting , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Línea Celular , Técnica del Anticuerpo Fluorescente , Humanos , Células MCF-7 , ARN Interferente Pequeño , Receptores Sensibles al Calcio/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Canal Catiónico TRPC6/genética , Proteína de Unión al GTP rhoA/genética
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