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2.
Neurol Med Chir (Tokyo) ; 63(12): 563-570, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37940569

RESUMO

Studies regarding hematoma stiffness and removal difficulty are scarce. This study explored the association between hematoma stiffness and surgical results of endoscopic hematoma removal for intracerebral hemorrhage. It also aimed to clarify factors associated with hematoma stiffness. We classified intracerebral hematoma as either soft or firm stiffness by retrospectively evaluating operative videos by two neurosurgeons. The interobserver reliability of the classification was assessed by calculating the κ values. We investigated the relationship between hematoma stiffness and surgical results. Favorable hematoma removal (FHR) was defined as a residual hematoma volume of ≤15 mL or removal rate of ≥70%. Furthermore, we compared the background characteristics, imaging findings, and laboratory data between the two groups. Forty patients were included in this study. The mean baseline hematoma volume was 69.9 mL (range, 41.3-97.6 mL). FHR was accomplished in 35 cases (87.5%). Thirty-four patients (85%) were in the soft hematoma group (group S). Six patients (15%) were in the firm hematoma group (group F). Classification of hematoma stiffness demonstrated an excellent degree of interobserver agreement (κ score = 0.91). Patients in group S had a high FHR rate (p = 0.018) and short endoscopic procedure times (p = 0.00034). The island sign was present in group S (p = 0.030). Patients in group F had significantly high fibrinogen levels (p = 0.049) and low serum total calcium (p = 0.032), hemoglobin (p = 0.041), and hematocrit (p = 0.011) levels. Hematoma stiffness during endoscopic surgery for intracerebral hemorrhage correlates with surgical results, including the endoscopic procedure time and accomplishing rate of FHR.


Assuntos
Hemorragia Cerebral , Relevância Clínica , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Resultado do Tratamento , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/cirurgia , Hematoma/diagnóstico por imagem , Hematoma/cirurgia
3.
bioRxiv ; 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37662303

RESUMO

Lung immune tone, i.e. the immune state of the lung, can vary between individuals and over a single individual's lifetime, and its basis and regulation in the context of inflammatory responses to injury is poorly understood. The gut microbiome, through the gut-lung axis, can influence lung injury outcomes but how the diet and microbiota affect lung immune tone is also unclear. We hypothesized that lung immune tone would be influenced by the presence of fiber-fermenting short-chain fatty acid (SCFA)-producing gut bacteria. To test this hypothesis, we conducted a fiber diet intervention study followed by lung injury in mice and profiled gut microbiota using 16S sequencing, metabolomics, and lung immune tone. We also studied germ-free mice to evaluate lung immune tone in the absence of microbiota and performed in vitro mechanistic studies on immune tone and metabolic programming of alveolar macrophages exposed to the SCFA propionate (C3). Mice on high-fiber diet were protected from sterile lung injury compared to mice on a fiber-free diet. This protection strongly correlated with lower lung immune tone, elevated propionate levels and enrichment of specific fecal microbiota taxa; conversely, lower levels of SCFAs and an increase in other fatty acid metabolites and bacterial taxa correlated with increased lung immune tone and increased lung injury in the fiber-free group. In vitro , C3 reduced lung alveolar macrophage immune tone (through suppression of IL-1ß and IL-18) and metabolically reprogrammed them (switching from glycolysis to oxidative phosphorylation after LPS challenge). Overall, our findings reveal that the gut-lung axis, through dietary fiber intake and enrichment of SCFA-producing gut bacteria, can regulate innate lung immune tone via IL-1ß and IL-18 pathways. These results provide a rationale for the therapeutic development of dietary interventions to preserve or enhance specific aspects of host lung immunity.

4.
Plant Cell Physiol ; 64(5): 454-460, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36943745

RESUMO

In the anthers and ovaries of flowers, pollen grains and embryo sacs are produced with uniform cell compositions. This stable gametogenesis enables elaborate interactions between male and female gametophytes after pollination, forming the highly successful sexual reproduction system in flowering plants. As most ovules are fertilized with a single pollen tube, the resulting genome set in the embryo and endosperm is determined in a single pattern by independent fertilization of the egg cell and central cell by two sperm cells. However, if ovules receive four sperm cells from two pollen tubes, the expected options for genome sets in the developing seeds would more than double. In wild-type Arabidopsis thaliana plants, around 5% of ovules receive two pollen tubes. Recent studies have elucidated the abnormal fertilization in supernumerary pollen tubes and sperm cells related to polytubey, polyspermy, heterofertilization and fertilization recovery. Analyses of model plants have begun to uncover the mechanisms underlying this new pollen tube biology. Here, we review unusual fertilization phenomena and propose several breeding applications for flowering plants. These arguments contribute to the remodeling of plant reproduction, a challenging concept that alters typical plant fertilization by utilizing the current genetic toolbox.


Assuntos
Arabidopsis , Sementes , Sementes/metabolismo , Arabidopsis/metabolismo , Pólen/genética , Tubo Polínico/genética , Fertilização/genética , Óvulo Vegetal/genética , Reprodução/genética
5.
Front Plant Sci ; 14: 1116289, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778680

RESUMO

In pollen and pollen tubes, immotile sperm cells are enclosed by an inner vegetative plasma membrane (IVPM), a single endomembrane originating from the vegetative-cell plasma membrane. It is widely believed that sperm cells must be removed from the IVPM prior to gamete associations and fusions; however, details of the timing and morphological changes upon IVPM dissociation remain elusive. Here, we report a rapid IVPM breakdown immediately before double fertilization in Arabidopsis thaliana. The IVPM was stably observed in coiling pollen tubes when pollen tube discharge was prevented using lorelei mutant ovules. In contrast, a semi-in vivo fertilization assay in wild-type ovules demonstrated fragmented IVPM around sperm nuclei 1 min after pollen tube discharge. These observations revealed the dynamic alteration of released sperm cells and provided new insights into double fertilization in flowering plants. With a summary of recent findings on IVPM lipid composition, we discussed the possible physiological signals controlling IVPM breakdown.

6.
FEBS Lett ; 597(3): 407-417, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36645411

RESUMO

Endosperm-embryo development in flowering plants is regulated coordinately by signal exchange during seed development. However, such a reciprocal control mechanism has not been clearly identified. In this study, we identified an endosperm-specific gene, LBD35, expressed in an embryonic development-dependent manner, by a comparative transcriptome and cytological analyses of double-fertilized and single-fertilized seeds prepared by using the kokopelli mutant, which frequently induces single fertilization events. Transcriptome analysis using LBD35 as a marker of the central cell fertilization event identified that 141 genes, including 31 genes for small cysteine-rich peptides, are expressed in a double fertilization-dependent manner. Our results reveal possible embryonic signals that regulate endosperm gene expression and provide a practicable method to identify genes involved in the communication during endosperm-embryo development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Endosperma/genética , Endosperma/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sementes/genética , Sementes/metabolismo , Desenvolvimento Embrionário , Perfilação da Expressão Gênica , Transcriptoma , Regulação da Expressão Gênica de Plantas
7.
Acta Neurochir (Wien) ; 165(2): 281-287, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36602615

RESUMO

PURPOSE: To determine the association between optic nerve sheath diameter (ONSD) and outcome in patients with traumatic brain injury (TBI) who undergo hematoma removal (HR). METHODS: This study was a retrospective analysis of data from a single center between 2016 and 2021. Adult patients with TBI who underwent HR within 24 h after admission were included in this study. Preoperative and postoperative ONSD of the surgical side and the mean ONSD of both sides were measured for analysis. The primary outcome was mortality at 30 days. Receiver operating characteristic curve analysis was performed to calculate the area under the curve (AUC) and 95% confidence interval (CI) for 30 days mortality. RESULTS: Sixty-one patients were enrolled in the study. Among them, 48 (78.7%) survived for 30 days after admission. The AUC and 95% CI of the postoperative mean ONSD on both sides and postoperative/preoperative mean of the ONSD ratio on both sides were 0.884 [0.734-0.955] and 0.875 [0.751-0.942], respectively. The postoperative mean of both ONSDs of 6.0 mm had high accuracy as a cut-off value with a sensitivity of 85%, specificity of 83%, positive likelihood ratio (LR) of 5.0, and negative LR- of 0.18. CONCLUSION: This study demonstrated that postoperative ONSD and the postoperative/preoperative ONSD ratio were associated with postoperative outcome in patients with TBI who underwent HR.


Assuntos
Lesões Encefálicas Traumáticas , Hipertensão Intracraniana , Adulto , Humanos , Estudos Retrospectivos , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/cirurgia , Pressão Intracraniana/fisiologia , Lesões Encefálicas Traumáticas/cirurgia , Hematoma , Ultrassonografia
8.
Neurocrit Care ; 38(3): 640-649, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36324002

RESUMO

BACKGROUND: Coagulopathy is often observed in severe traumatic brain injury (sTBI), and hyperfibrinolysis (HF) is associated with a poor prognosis. Although the efficacy of fibrinogen concentrate (FC) in multiple trauma has been reported, its efficacy in sTBI is unclear. Therefore, we delineated severe HF risk factors despite fresh frozen plasma transfusion. Using these risk factors, we defined high-risk patients and determined whether FC administration to this group improved fibrinogen level. METHODS: In the first part of this study, successive adults with sTBI treated at our hospital between April 2016 and March 2019 were reviewed. Patients underwent transfusion as per our conventional protocol and were divided into two groups based on whether fibrinogen levels of ≥ 150 mg/dL were maintained 3-6 h after arrival to delineate the risk factors of severe HF. In the second part of the study, we conducted a before-and-after study in patients with sTBI who were at a higher risk for severe HF (presence of at least one of the risk factors identified in the first part of the study), comparing those treated with FC between April 2019 and March 2021 (FC group) with those treated with conventional transfusion before FC between April 2016 and March 2019. The primary outcome was maintenance of fibrinogen levels, and the secondary outcome was 30-day mortality. RESULTS: In the first part of the study, 78 patients were included. Twenty-three patients did not maintain fibrinogen levels ≥ 150 mg/dL. A D-dimer level on arrival > 50 µg/mL, a fibrinogen level on arrival < 200 mg/dL, depressed skull fracture, and multiple trauma were severe HF risk factors. In the second part, compared with 46 patients who were identified as being at high risk for severe HF but were not administered FC (non-FC group), fibrinogen levels ≥ 150 mg/dL 3-6 h after arrival were maintained in 14 of 15 patients in the FC group (odds ratio: 0.07; 95% confidence interval: 0.01-0.59). Although there were significant differences in fibrinogen levels, no significant differences were observed in terms of 30-day mortality between the groups. CONCLUSIONS: Coagulation abnormalities on arrival, severe skull fracture, and multiple trauma are severe HF risk factors. FC administration may contribute to rapid correction of developing hypofibrinogenemia.


Assuntos
Afibrinogenemia , Transtornos da Coagulação Sanguínea , Lesões Encefálicas Traumáticas , Traumatismo Múltiplo , Adulto , Humanos , Fibrinogênio , Afibrinogenemia/tratamento farmacológico , Transfusão de Componentes Sanguíneos , Plasma , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/etiologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico
9.
Plant Cell ; 35(4): 1222-1240, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36562145

RESUMO

Pollen tube attraction is a key event of sexual reproduction in flowering plants. In the ovule, two synergid cells neighboring the egg cell control pollen tube arrival via the active secretion of attractant peptides such as AtLURE1 and XIUQIU from the filiform apparatus (FA) facing toward the micropyle. Distinctive cell polarity together with longitudinal F-actin and microtubules are hallmarks of the synergid cell in various species, though the functions of these cellular structures are unclear. In this study, we used genetic and pharmacological approaches to indicate the roles of cytoskeletal components in FA formation and pollen tube guidance in Arabidopsis thaliana. Genetic inhibition of microtubule formation reduced invaginations of the plasma membrane but did not abolish micropylar AtLURE1.2 accumulation. By contrast, the expression of a dominant-negative form of ACTIN8 induced disorganization of the FA and loss of polar AtLURE1.2 distribution toward the FA. Interestingly, after pollen tube reception, F-actin became unclear for a few hours in the persistent synergid cell, which may be involved in pausing and resuming pollen tube attraction during early polytubey block. Our data suggest that F-actin plays a central role in maintaining cell polarity and in mediating male-female communication in the synergid cell.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Actinas/genética , Actinas/metabolismo , Tubo Polínico/genética , Tubo Polínico/metabolismo , Membrana Celular/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo
10.
Plant Cell Physiol ; 64(1): 117-123, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36264192

RESUMO

Apomixis, defined as the transfer of maternal germplasm to offspring without fertilization, enables the fixation of F1-useful traits, providing advantages in crop breeding. However, most apomictic plants require pollination to produce the endosperm. The endosperm is essential for embryogenesis, and its development is suppressed until fertilization. We show that the expression of a chimeric repressor of the Elongation of Siliques without Pollination 3 (ESP3) gene (Pro35S:ESP3-SRDX) induces ovule enlargement without fertilization in Arabidopsis thaliana. The ESP3 gene encodes a protein similar to the flowering Wageningen homeodomain transcription factor containing a StAR-related lipid transfer domain. However, ESP3 lacks the homeobox-encoding region. Genes related to the cell cycle and sugar metabolism were upregulated in unfertilized Pro35S:ESP3-SRDX ovules similar to those in fertilized seeds, while those related to autophagy were downregulated similar to those in fertilized seeds. Unfertilized Pro35S:ESP3-SRDX ovules partially nourished embryos when only the egg was fertilized, accumulating hexoses without central cell proliferation. ESP3 may regulate nutrient flow during seed development, and ESP3-SRDX could be a useful tool for complete apomixis that does not require pseudo-fertilization.


Assuntos
Arabidopsis , Polinização , Sementes/metabolismo , Endosperma/genética , Reprodução , Arabidopsis/genética , Desenvolvimento Embrionário , Óvulo Vegetal/genética
11.
Br J Neurosurg ; 37(4): 604-607, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31364414

RESUMO

N-butyl cyanoacrylate (NBCA) has been used to embolise brain arteriovenous malformations (AVMs) for over 30 years. It is a mixed with lipiodol in varying proportions. We report a 22-year-old male with intraventricular hemorrhage from a ruptured intranidal AVM aneurysm in the left temporal lobe. The intranidal aneurysm and the nidus were successfully embolized using a 20% NBCA and lipiodol mixture without any complications according to computed tomography (CT) immediately after treatment. Scattered high-density spots were observed in both lateral ventricles on CT 5 days after embolization, suggesting migration of lipiodol. We speculated that the aneurysm was a pseudoaneurysm whose wall protruded into the inferior horn of the left lateral ventricle, and the lipiodol in the NBCA migrated into the ventricles after the thin part of the wall ruptured. The patient developed pyrexia due to chemical meningitis, which responded to steroid treatment for one month.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Embucrilato , Malformações Arteriovenosas Intracranianas , Masculino , Humanos , Adulto Jovem , Adulto , Óleo Etiodado , Ventrículos Laterais , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/terapia , Malformações Arteriovenosas Intracranianas/complicações , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/terapia , Aneurisma Roto/complicações , Embucrilato/uso terapêutico
12.
Front Plant Sci ; 13: 1020306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36507386

RESUMO

The vegetative cell nucleus proceeds ahead of a pair of sperm cells located beneath the pollen tube tip during germination. The tip-localized vegetative nucleus had been considered to play a pivotal role in the control of directional pollen tube growth and double fertilization. However, we recently reported the female-targeting behavior of pollen tubes from mutant plants, of which the vegetative nucleus and sperm nuclei were artificially immotile. We showed that the apical region of the mutant pollen tubes became physiologically enucleated after the first callose plug formation, indicating the autonomously growing nature of pollen tubes without the vegetative nucleus and sperm cells. Thus, in this study, we further analyzed another Arabidopsis thaliana mutant producing physiologically enucleated pollen tubes and discussed the mechanism by which a pollen tube can grow without de novo transcription from the vegetative nucleus. We propose several possible molecular mechanisms for persistent pollen tube growth, such as the contribution of transcripts before and immediately after germination and the use of persistent transcripts, which may be important for a competitive race among pollen tubes.

13.
J Vis Exp ; (187)2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36155626

RESUMO

Ischemia reperfusion (IR) injury frequently results from processes that involve a transient period of interrupted blood flow. In the lung, isolated IR permits the experimental study of this specific process with continued alveolar ventilation, thereby avoiding the compounding injurious processes of hypoxia and atelectasis. In the clinical context, lung ischemia reperfusion injury (also known as lung IRI or LIRI) is caused by numerous processes, including but not limited to pulmonary embolism, resuscitated hemorrhagic trauma, and lung transplantation. There are currently limited effective treatment options for LIRI. Here, we present a reversible surgical model of lung IR involving first orotracheal intubation followed by unilateral left lung ischemia and reperfusion with preserved alveolar ventilation or gas exchange. Mice undergo a left thoracotomy, through which the left pulmonary artery is exposed, visualized, isolated, and compressed using a reversible slipknot. The surgical incision is then closed during the ischemic period, and the animal is awakened and extubated. With the mouse spontaneously breathing, reperfusion is established by releasing the slipknot around the pulmonary artery. This clinically relevant survival model permits the evaluation of lung IR injury, the resolution phase, downstream effects on lung function, as well as two-hit models involving experimental pneumonia. While technically challenging, this model can be mastered over the course of a few weeks to months with an eventual survival or success rate of 80%-90%.


Assuntos
Pneumopatias , Traumatismo por Reperfusão , Animais , Modelos Animais de Doenças , Intubação Intratraqueal/efeitos adversos , Isquemia , Pulmão/irrigação sanguínea , Camundongos , Reperfusão/efeitos adversos
15.
Surg Neurol Int ; 13: 26, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35127226

RESUMO

BACKGROUND: Fibromuscular dysplasia (FMD) can cause cerebral aneurysms and dissection, which can lead to stroke. Angiographic findings are important in the diagnosis. We report a case of FMD in which the cause of hemorrhage could not be determined by angiography. CASE DESCRIPTION: A 73-year-old woman suffered from intracerebral hemorrhage (ICH) associated with FMD without abnormal angiography cerebral vessels. She presented with headache and nausea. Subsequent head-computed tomography-revealed ICH in the left frontal lobe, and contrast-enhanced magnetic resonance imaging revealed a gadolinium-enhancing lesion in the perihematoma area and in the genu of the corpus callosum. Although cerebral angiography revealed a string of beads appearance in the bilateral extracranial internal carotid arteries, no abnormality explaining the hemorrhage was identified. The hematoma was removed and the pathological diagnosis was FMD. In the pathological specimen, various patterns of vulnerable vessels, such as aneurysmal dilatation and obstruction, were observed, which could easily collapse and result in hemorrhage. In the case of ICH of unknown origin, microscopic vessel disruption due to FMD should also be considered. CONCLUSION: FMD can cause ICH in microscopic vascular lesions that are undetectable on angiography.

16.
Acta Neurochir (Wien) ; 164(1): 169-172, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34850290

RESUMO

Balloon test occlusion (BTO) can predict the ischemic complication risk associated with arterial occlusion. We present a case of an unruptured, broad-necked internal carotid artery-posterior communicating artery (PcomA) aneurysm that was successfully embolized after super-selective BTO of fetal PcomA with electrophysiological monitoring. The proximal portion of the PcomA was internally occluded without causing major neurological deficits, although we observed a small new infarction in the ipsilateral anterior thalamus postoperatively. We recognized small perforators arising from the proximal PcomA during a previous clipping surgery. Super-selective BTO with electrophysiological monitoring could be useful for functional preservation after infarction from angiographically invisible perforators.


Assuntos
Arteriopatias Oclusivas , Doenças das Artérias Carótidas , Aneurisma Intracraniano , Artéria Carótida Interna , Círculo Arterial do Cérebro , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia
17.
Front Pediatr ; 9: 662953, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026693

RESUMO

Kawasaki disease (KD), an acute febrile childhood illness and systemic vasculitis of unknown etiology, is the leading cause of acquired heart disease among children. Experimental data from murine models of KD vasculitis and transcriptomics data generated from whole blood of KD patients indicate the involvement of the NLRP3 inflammasome and interleukin-1 (IL-1) signaling in KD pathogenesis. MicroRNA-223 (miR-223) is a negative regulator of NLRP3 activity and IL-1ß production, and its expression has been reported to be upregulated during acute human KD; however, the specific role of miR-223 during KD vasculitis remains unknown. Here, using the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis, we demonstrate increased miR-223 expression in LCWE-induced cardiovascular lesions. Compared with control WT mice, LCWE-injected miR-223-deficient mice (miR223 -/y ) developed more severe coronary arteritis and aortitis, as well as more pronounced abdominal aorta aneurysms and dilations. The enhanced cardiovascular lesions and KD vasculitis observed in LCWE-injected miR223 -/y mice correlated with increased NLRP3 inflammasome activity and elevated IL-1ß production, indicating that miR-223 limits cardiovascular lesion development by downmodulating NLRP3 inflammasome activity. Collectively, our data reveal a previously unappreciated role of miR-223 in regulating innate immune responses and in limiting KD vasculitis and its cardiovascular lesions by constraining the NLRP3 inflammasome and the IL-1ß pathway. These data also suggest that miR-223 expression may be used as a marker for KD vasculitis pathogenesis and provide a novel therapeutic target.

18.
Nat Commun ; 12(1): 2331, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888710

RESUMO

During the double fertilization process, pollen tubes deliver two sperm cells to an ovule containing the female gametes. In the pollen tube, the vegetative nucleus and sperm cells move together to the apical region where the vegetative nucleus is thought to play a crucial role in controlling the direction and growth of the pollen tube. Here, we report the generation of pollen tubes in Arabidopsis thaliana whose vegetative nucleus and sperm cells are isolated and sealed by callose plugs in the basal region due to apical transport defects induced by mutations in the WPP domain-interacting tail-anchored proteins (WITs) and sperm cell-specific expression of a dominant mutant of the CALLOSE SYNTHASE 3 protein. Through pollen-tube guidance assays, we show that the physiologically anuclear mutant pollen tubes maintain the ability to grow and enter ovules. Our findings provide insight into the sperm cell delivery mechanism and illustrate the independence of the tip-localized vegetative nucleus from directional growth control of the pollen tube.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Núcleo Celular/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Polinização/fisiologia , Proteínas de Arabidopsis/genética , Movimento Celular/fisiologia , Fertilização/fisiologia , Glucanos/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Óvulo Vegetal/metabolismo , Plantas Geneticamente Modificadas , Tubo Polínico/citologia , Tubo Polínico/metabolismo
19.
Am J Physiol Lung Cell Mol Physiol ; 321(1): L65-L78, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33851870

RESUMO

Microbial metabolites produced by the gut microbiome, e.g. short-chain fatty acids (SCFA), have been found to influence lung physiology and injury responses. However, how lung immune activity is regulated by SCFA is unknown. We examined fresh human lung tissue and observed the presence of SCFA with interindividual variability. In vitro, SCFA were capable of modifying the metabolic programming in LPS-exposed alveolar macrophages (AM). We hypothesized that lung immune tone could be defined by baseline detection of lung intracellular IL-1ß. Therefore, we interrogated naïve mouse lungs with intact gut microbiota for IL-1ß mRNA expression and localized its presence within alveolar spaces, specifically within AM subsets. We established that metabolically active gut microbiota, which produce SCFA, can transmit LPS and SCFA to the lung and thereby could create primed lung immunometabolic tone. To understand how murine lung cells sensed and upregulated IL-1ß in response to gut microbiome-derived factors, we determined that, in vitro, AM and alveolar type II (AT2) cells expressed SCFA receptors, free fatty acid receptor 2 (FFAR2), free fatty acid receptor 3 (FFAR3), and IL-1ß but with distinct expression patterns and different responses to LPS. Finally, we observed that IL-1ß, FFAR2, and FFAR3 were expressed in isolated human AM and AT2 cells ex vivo, but in fresh human lung sections in situ, only AM expressed IL-1ß at rest and after LPS challenge. Together, this translational study using mouse and human lung tissue and cells point to an important role for the gut microbiome and their SCFA in establishing and regulating lung immune tone.


Assuntos
Ácidos Graxos Voláteis/farmacologia , Trato Gastrointestinal/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Pulmão/imunologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Feminino , Humanos , Interleucina-1beta/genética , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G/genética
20.
PLoS Biol ; 19(3): e3001123, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33770073

RESUMO

The female gametophytes of angiosperms contain cells with distinct functions, such as those that enable reproduction via pollen tube attraction and fertilization. Although the female gametophyte undergoes unique developmental processes, such as several rounds of nuclear division without cell plate formation and final cellularization, it remains unknown when and how the cell fate is determined during development. Here, we visualized the living dynamics of female gametophyte development and performed transcriptome analysis of individual cell types to assess the cell fate specifications in Arabidopsis thaliana. We recorded time lapses of the nuclear dynamics and cell plate formation from the 1-nucleate stage to the 7-cell stage after cellularization using an in vitro ovule culture system. The movies showed that the nuclear division occurred along the micropylar-chalazal (distal-proximal) axis. During cellularization, the polar nuclei migrated while associating with the forming edge of the cell plate, and then, migrated toward each other to fuse linearly. We also tracked the gene expression dynamics and identified that the expression of MYB98pro::GFP-MYB98, a synergid-specific marker, was initiated just after cellularization in the synergid, egg, and central cells and was then restricted to the synergid cells. This indicated that cell fates are determined immediately after cellularization. Transcriptome analysis of the female gametophyte cells of the wild-type and myb98 mutant revealed that the myb98 synergid cells had egg cell-like gene expression profiles. Although in myb98, egg cell-specific gene expression was properly initiated in the egg cells only after cellularization, but subsequently expressed ectopically in one of the 2 synergid cells. These results, together with the various initiation timings of the egg cell-specific genes, suggest complex regulation of the individual gametophyte cells, such as cellularization-triggered fate initiation, MYB98-dependent fate maintenance, cell morphogenesis, and organelle positioning. Our system of live-cell imaging and cell type-specific gene expression analysis provides insights into the dynamics and mechanisms of cell fate specifications in the development of female gametophytes in plants.


Assuntos
Arabidopsis/metabolismo , Diferenciação Celular/genética , Óvulo Vegetal/metabolismo , Proteínas de Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Magnoliopsida/metabolismo , Morfogênese , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Tubo Polínico/genética , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genética
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