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1.
Proc Natl Acad Sci U S A ; 121(5): e2313656121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252822

RESUMO

Long non-coding RNA (lncRNA) serves as a vital regulator of bone metabolism, but its role in pathologically overactive osteoclast differentiation remains elusive. Here, we identify lncRNA Dancr (Differentiation Antagonizing Non-protein Coding RNA) as a critical suppressor of osteoclastogenesis and bone resorption, which is down-regulated in response to estrogen deficiency. Global or osteoclast-specific Dancr Knockout mice display significant trabecular bone deterioration and enhanced osteoclast activity, but minimal alteration of bone formation. Moreover, the bone-targeted delivery of Dancr by Adeno-associated viral remarkably attenuates ovariectomy-induced osteopenia in mice. Mechanistically, Dancr establishes a direct interaction with Brahma-related gene 1 to prevent its binding and preserve H3K27me3 enrichment at the nuclear factor of activated T cells 1 and proliferator-activated receptor gamma coactivator 1-beta promoters, thereby maintaining appropriate expression of osteoclastic genes and metabolic programs during osteoclastogenesis. These results demonstrate that Dancr is a key molecule maintaining proper osteoclast differentiation and bone homeostasis under physiological conditions, and Dancr overexpression constitutes a potential strategy for treating osteoporosis.


Assuntos
Fatores de Transcrição NFATC , Osteogênese , RNA Longo não Codificante , Fatores de Transcrição , Animais , Feminino , Camundongos , Homeostase , Camundongos Knockout , Fatores de Transcrição NFATC/genética , Osteoclastos , Osteogênese/genética , RNA Longo não Codificante/genética , Fatores de Transcrição/genética
2.
Semin Cancer Biol ; 95: 75-87, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37499847

RESUMO

Radiomics is the extraction of predefined mathematic features from medical images for predicting variables of clinical interest. Recent research has demonstrated that radiomics can be processed by artificial intelligence algorithms to reveal complex patterns and trends for diagnosis, and prediction of prognosis and response to treatment modalities in various types of cancer. Artificial intelligence tools can utilize radiological images to solve next-generation issues in clinical decision making. Bone tumors can be classified as primary and secondary (metastatic) tumors. Osteosarcoma, Ewing sarcoma, and chondrosarcoma are the dominating primary tumors of bone. The development of bone tumor model systems and relevant research, and the assessment of novel treatment methods are ongoing to improve clinical outcomes, notably for patients with metastases. Artificial intelligence and radiomics have been utilized in almost full spectrum of clinical care of bone tumors. Radiomics models have achieved excellent performance in the diagnosis and grading of bone tumors. Furthermore, the models enable to predict overall survival, metastases, and recurrence. Radiomics features have exhibited promise in assisting therapeutic planning and evaluation, especially neoadjuvant chemotherapy. This review provides an overview of the evolution and opportunities for artificial intelligence in imaging, with a focus on hand-crafted features and deep learning-based radiomics approaches. We summarize the current application of artificial intelligence-based radiomics both in primary and metastatic bone tumors, and discuss the limitations and future opportunities of artificial intelligence-based radiomics in this field. In the era of personalized medicine, our in-depth understanding of emerging artificial intelligence-based radiomics approaches will bring innovative solutions to bone tumors and achieve clinical application.


Assuntos
Inteligência Artificial , Neoplasias Ósseas , Humanos , Diagnóstico por Imagem , Prognóstico , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/terapia
3.
J Neurosci ; 43(9): 1456-1474, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36653190

RESUMO

RNA N6-methyladenosine (m6A) modification is involved in diverse biological processes. However, its role in spinal cord injury (SCI) is poorly understood. The m6A level increases in injured spinal cord, and METTL3, which is the core subunit of methyltransferase complex, is upregulated in reactive astrocytes and further stabilized by the USP1/UAF1 complex after SCI. The USP1/UAF1 complex specifically binds to and subsequently removes K48-linked ubiquitination of the METTL3 protein to maintain its stability after SCI. Moreover, conditional knockout of astrocytic METTL3 in both sexes of mice significantly suppressed reactive astrogliosis after SCI, thus resulting in widespread infiltration of inflammatory cells, aggravated neuronal loss, hampered axonal regeneration, and impaired functional recovery. Mechanistically, the YAP1 transcript was identified as a potential target of METTL3 in astrocytes. METTL3 could selectively methylate the 3'-UTR region of the YAP1 transcript, which subsequently maintains its stability in an IGF2BP2-dependent manner. In vivo, YAP1 overexpression by adeno-associated virus injection remarkably contributed to reactive astrogliosis and partly reversed the detrimental effects of METTL3 knockout on functional recovery after SCI. Furthermore, we found that the methyltransferase activity of METTL3 plays an essential role in reactive astrogliosis and motor repair, whereas METTL3 mutant without methyltransferase function failed to promote functional recovery after SCI. Our study reveals the previously unreported role of METTL3-mediated m6A modification in SCI and might provide a potential therapy for SCI.SIGNIFICANCE STATEMENT Spinal cord injury is a devastating trauma of the CNS involving motor and sensory impairments. However, epigenetic modification in spinal cord injury is still unclear. Here, we propose an m6A regulation effect of astrocytic METTL3 following spinal cord injury, and we further characterize its underlying mechanism, which might provide promising strategies for spinal cord injury treatment.


Assuntos
Gliose , Traumatismos da Medula Espinal , Animais , Feminino , Masculino , Camundongos , Astrócitos/metabolismo , Gliose/metabolismo , Inflamação/metabolismo , Metiltransferases/metabolismo , Metiltransferases/farmacologia , RNA Mensageiro/metabolismo , Medula Espinal/metabolismo
4.
Small ; : e2311344, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661278

RESUMO

The effect of immunoinflammation on bone repair during the recovery process of bone defects needs to be further explored. It is reported that Mg2+ can promote bone repair with immunoregulatory effect, but the underlying mechanism on adaptive immunity is still unclear. Here, by using chitosan and hyaluronic acid-coated Mg2+ (CSHA-Mg) in bone-deficient mice, it is shown that Mg2+ can inhibit the activation of CD4+ T cells and increase regulatory T cell formation by inducing immunosuppressive dendritic cells (imDCs). Mechanistically, Mg2+ initiates the activation of the MAPK signaling pathway through TRPM7 channels on DCs. This process subsequently induces the downstream HIF-1α expression, a transcription factor that amplifies TGF-ß production and inhibits the effective T cell function. In vivo, knock-out of HIF-1α in DCs or using a HIF-1α inhibitor PX-478 reverses inhibition of bone inflammation and repair promotion upon Mg2+-treatment. Moreover, roxadustat, which stabilizes HIF-1α protein expression, can significantly promote immunosuppression and bone repair in synergism with CSHA-Mg. Thus, the findings identify a key mechanism for DCs and its HIF-1α-TGF-ß axis in the induction of immunosuppressive bone microenvironment, providing potential targets for bone regeneration.

5.
Glob Chang Biol ; 30(5): e17304, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38711381

RESUMO

Subtropical forests, recognized for their intricate vertical canopy stratification, exhibit high resistance to extreme drought. However, the response of leaf phenology to drought in the species-rich understory remains poorly understood. In this study, we constructed a digital camera system, amassing over 360,000 images through a 70% throughfall exclusion experiment, to explore the drought response of understory leaf phenology. The results revealed a significant advancement in understory leaf senescence phenology under drought, with 11.75 and 15.76 days for the start and end of the leaf-falling event, respectively. Pre-season temperature primarily regulated leaf development phenology, whereas soil water dominated the variability in leaf senescence phenology. Under drought conditions, temperature sensitivities for the end of leaf emergence decreased from -13.72 to -11.06 days °C-1, with insignificance observed for the start of leaf emergence. Consequently, drought treatment shortened both the length of the growing season (15.69 days) and the peak growth season (9.80 days) for understory plants. Moreover, this study identified diverse responses among intraspecies and interspecies to drought, particularly during the leaf development phase. These findings underscore the pivotal role of water availability in shaping understory phenology patterns, especially in subtropical forests.


Assuntos
Secas , Folhas de Planta , Estações do Ano , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Temperatura , Florestas , Água/metabolismo , Árvores/crescimento & desenvolvimento , Árvores/fisiologia , Solo , Clima Tropical , China
6.
Glob Chang Biol ; 30(6): e17338, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822535

RESUMO

Nitrogen (N) immobilization (Nim, including microbial N assimilation) and plant N uptake (PNU) are the two most important pathways of N retention in soils. The ratio of Nim to PNU (hereafter Nim:PNU ratio) generally reflects the degree of N limitation for plant growth in terrestrial ecosystems. However, the key factors driving the pattern of Nim:PNU ratio across global ecosystems remain unclear. Here, using a global data set of 1018 observations from 184 studies, we examined the relative importance of mycorrhizal associations, climate, plant, and soil properties on the Nim:PNU ratio across terrestrial ecosystems. Our results show that mycorrhizal fungi type (arbuscular mycorrhizal (AM) or ectomycorrhizal (EM) fungi) in combination with soil inorganic N mainly explain the global variation in the Nim:PNU ratio in terrestrial ecosystems. In AM fungi-associated ecosystems, the relationship between Nim and PNU displays a weaker negative correlation (r = -.06, p < .001), whereas there is a stronger positive correlation (r = .25, p < .001) in EM fungi-associated ecosystems. Our meta-analysis thus suggests that the AM-associated plants display a weak interaction with soil microorganisms for N absorption, while EM-associated plants cooperate with soil microorganisms. Furthermore, we find that the Nim:PNU ratio for both AM- and EM-associated ecosystems gradually converge around a stable value (13.8 ± 0.5 for AM- and 12.1 ± 1.2 for EM-associated ecosystems) under high soil inorganic N conditions. Our findings highlight the dependence of plant-microbial interaction for N absorption on both plant mycorrhizal association and soil inorganic N, with the stable convergence of the Nim:PNU ratio under high soil N conditions.


Assuntos
Micorrizas , Nitrogênio , Microbiologia do Solo , Solo , Micorrizas/fisiologia , Micorrizas/metabolismo , Nitrogênio/metabolismo , Solo/química , Plantas/metabolismo , Plantas/microbiologia , Ecossistema
7.
Mol Cell Biochem ; 479(4): 811-823, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37188988

RESUMO

Cilia are tiny organelles with conserved structures and components in eukaryotic cells. Ciliopathy is a set of diseases resulting from cilium dysfunction classified into first-order and second-order ciliopathy. With the advancement of clinical diagnosis and radiography, numerous skeletal phenotypes, including polydactyly, short limbs, short ribs, scoliosis, a narrow thorax, and numerous anomalies in bone and cartilage, have been discovered in ciliopathies. Mutation in genes encoding cilia core components or other cilia-related molecules have been found in skeletal ciliopathies. Meanwhile, various signaling pathways associated with cilia and skeleton development have been deemed to be significant for the occurrence and progression of diseases. Herein, we review the structure and key components of the cilium and summarize several skeletal ciliopathies with their presumable pathology. We also emphasize the signaling pathways involved in skeletal ciliopathies, which may assist in developing potential therapies for these diseases.


Assuntos
Ciliopatias , Humanos , Ciliopatias/genética , Ciliopatias/patologia , Mutação , Transdução de Sinais , Fenótipo , Cílios
8.
Eur Radiol ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904758

RESUMO

OBJECTIVES: This study investigated the diagnostic performance of dual-energy computed tomography (CT) and deep learning for the preoperative classification of equivocal lymph nodes (LNs) on CT images in thyroid cancer patients. METHODS: In this prospective study, from October 2020 to March 2021, 375 patients with thyroid disease underwent thin-section dual-energy thyroid CT at a small field of view (FOV) and thyroid surgery. The data of 183 patients with 281 LNs were analyzed. The targeted LNs were negative or equivocal on small FOV CT images. Six deep-learning models were used to classify the LNs on conventional CT images. The performance of all models was compared with pathology reports. RESULTS: Of the 281 LNs, 65.5% had a short diameter of less than 4 mm. Multiple quantitative dual-energy CT parameters significantly differed between benign and malignant LNs. Multivariable logistic regression analyses showed that the best combination of parameters had an area under the curve (AUC) of 0.857, with excellent consistency and discrimination, and its diagnostic accuracy and sensitivity were 74.4% and 84.2%, respectively (p < 0.001). The visual geometry group 16 (VGG16) based model achieved the best accuracy (86%) and sensitivity (88%) in differentiating between benign and malignant LNs, with an AUC of 0.89. CONCLUSIONS: The VGG16 model based on small FOV CT images showed better diagnostic accuracy and sensitivity than the spectral parameter model. Our study presents a noninvasive and convenient imaging biomarker to predict malignant LNs without suspicious CT features in thyroid cancer patients. CLINICAL RELEVANCE STATEMENT: Our study presents a deep-learning-based model to predict malignant lymph nodes in thyroid cancer without suspicious features on conventional CT images, which shows better diagnostic accuracy and sensitivity than the regression model based on spectral parameters. KEY POINTS: Many cervical lymph nodes (LNs) do not express suspicious features on conventional computed tomography (CT). Dual-energy CT parameters can distinguish between benign and malignant LNs. Visual geometry group 16 model shows superior diagnostic accuracy and sensitivity for malignant LNs.

9.
Addict Biol ; 29(2): e13367, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38380757

RESUMO

Alcohol use disorder (AUD) has been associated with attentional deficits and impairments of working memory. Meanwhile, attention and working memory are critical for time perception. However, it remains unclear how time perception alters in AUD patients and how attention and working memory affect their time perception. The current study aims to clarify the time perception characteristics of AUD patients and the cognitive mechanisms underlying their time perception dysfunction. Thirty-one patients (three of them were excluded) with AUD and thirty-one matched controls completed the Time Bisection Task, Attention Network Test and Digital Span Backward Test to assess their abilities in time perception, attention network and working memory, respectively. The results showed that, after controlling for anxiety, depression, and impulsivity, AUD patients had a lower proportion of 'long' responses at intervals of 600, 750, 900, 1050 and 1200 ms. Furthermore, they displayed higher subjective equivalence points and higher Weber ratios compared to controls. Moreover, AUD patients showed impaired alerting and executive control networks as well as reduced working memory resources. Only working memory resources mediated the impact of AUD on time perception. In conclusion, our findings suggested that the duration underestimation in AUD patients is predominantly caused by working memory deficits.


Assuntos
Alcoolismo , Percepção do Tempo , Humanos , Memória de Curto Prazo/fisiologia , Função Executiva/fisiologia , Consumo de Bebidas Alcoólicas
10.
BMC Anesthesiol ; 24(1): 177, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762729

RESUMO

BACKGROUND: Post-anesthetic emergence agitation is common after general anesthesia and may cause adverse consequences, such as injury as well as respiratory and circulatory complications. Emergence agitation after general anesthesia occurs more frequently in nasal surgery than in other surgical procedures. This study aimed to assess the occurrence of emergence agitation in patients undergoing nasal surgery who were extubated under deep anesthesia or when fully awake. METHODS: A total of 202 patients (18-60 years, American Society of Anesthesiologists classification: I-II) undergoing nasal surgery under general anesthesia were randomized 1:1 into two groups: a deep extubation group (group D) and an awake extubation group (group A). The primary outcome was the incidence of emergence agitation. The secondary outcomes included number of emergence agitations, sedation score, vital signs, and incidence of adverse events. RESULTS: The incidence of emergence agitation was lower in group D than in group A (34.7% vs. 72.8%; p < 0.001). Compared to group A, patients in group D had lower Richmond Agitation-Sedation Scale scores, higher Ramsay sedation scores, fewer agitation episodes, and lower mean arterial pressure when extubated and 30 min after surgery, whereas these indicators did not differ 90 min after surgery. There was no difference in the incidence of adverse events between the two groups. CONCLUSIONS: Extubation under deep anesthesia can significantly reduce emergence agitation after nasal surgery under general anesthesia without increasing the incidence of adverse events. TRIAL REGISTRATION: Registered in Clinicaltrials.gov (NCT04844333) on 14/04/2021.


Assuntos
Extubação , Anestesia Geral , Delírio do Despertar , Procedimentos Cirúrgicos Nasais , Humanos , Extubação/métodos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Delírio do Despertar/prevenção & controle , Delírio do Despertar/epidemiologia , Delírio do Despertar/etiologia , Anestesia Geral/métodos , Procedimentos Cirúrgicos Nasais/métodos , Procedimentos Cirúrgicos Nasais/efeitos adversos , Adulto Jovem , Adolescente , Vigília , Período de Recuperação da Anestesia
11.
J Stroke Cerebrovasc Dis ; 33(6): 107682, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522758

RESUMO

OBJECTIVE: To assess the correlation between lesion location and swallowing function characteristics in post-stroke dysphagia (PSD) patients. MATERIALS AND METHODS: We enrolled 133 PSD. The patients were divided into supratentorial and infratentorial stroke groups. We compared the measurements in the videofluoroscopic swallowing study (VFSS) with 3ml and 5 ml of diluted and thickened barium liquid data between supratentorial and brainstem stroke groups. We further compared the difference of VFSS measurements between patients with left hemispheric or right hemispheric lesions (further divided into unilateral hemispheric cortical and subcortical subgroups) and brianstem leison stroke group.To explore the lesion location's effect on different bolus volume, the VFSS measurements of 3ml and 5ml in each subgroups were compared respectively. The measurements of VFSS included the oral transit time, soft palate elevation duration, hyoid bone movement duration (HMD), UES opening duration, pharyngeal transit duration (PTD), stage of ansition duration, and laryngeal closure duration (LCD), the upper esophageal sphincter opening (UESO), hyoid bone superior horizontal displacement, and hyoid bone anterior horizontal displacement. General swallowing function was assessed using the Penetration Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS). We performed the paired t-test, Spearman's correlation, and Kruskal-Wallis test analysis to characterize the parameters among the groups. RESULTS: Fifty-eight patients were assessed in the final analysis. The HMD (p = 0.019), PTD (p = 0.048) and LCD (p = 0.013) were significantly different between the supratentorial and brainstem lesion groups in 5ml volume. The HMD was significantly different (p = 0.045) between the left cortical and brainstem lesion groups. Significant differences in the HMD (p = 0.037) and LCD (p = 0.032) between the left subcortical and brainstem lesion groups were found in 5ml volume bolus. There was no group different when taking the 3ml volume bolus. Regarding the relationship between food bolus volume and swallowing functions, only the UESO demonstrated a significant difference in the subcortical lesion of the right hemisphere (p = 0.0032) compared the 3 ml and 5 ml volume bolus. The PTD demonstrated a moderate correlation with the PAS scores (r = 0.38, p = 0.0044). The HMD (r = 0.32, p = 0.018) and LCD (r = 0.29, p = 0.039) demonstrated weak correlations with the PAS scores. We did not identify any correlation between the VFSS parameters and FOIS scores in each subgroup level. CONCLUSION: The PSD with brainstem lesion shows more sever dysfunction in the pharyngeal phases. The left hemisphere was engaged in both the oral and pharyngeal phases. Lesions in the bilateral cortical, subcortical, and brainstem regions may impair sensory input.


Assuntos
Transtornos de Deglutição , Deglutição , Acidente Vascular Cerebral , Gravação em Vídeo , Humanos , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/diagnóstico por imagem , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Fluoroscopia , Valor Preditivo dos Testes , Idoso de 80 Anos ou mais , Fatores de Tempo , Fatores de Risco , Estudos Retrospectivos
12.
Funct Integr Genomics ; 23(1): 76, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36867323

RESUMO

Cervical giant cell tumor of the bone (GCTB) is a rare, primary benign bone tumor in pediatric patients. Surgery remains the primary choice for treating resectable cervical GCTB. Additional adjuvant therapeutic options are available for patients with unresectable cervical GCTB, including the anti-RANKL monoclonal antibody, denosumab. We represented a case incidentally found in a 7-year-old female, who complained severe craniocervical pain, grade 2-3 dysphagia, dysphonia, hypesthesia, and extremity weakness. The patient showed an impressive clinical response to denosumab, both clinically and radiologically, without adverse events or recurrence. To date, this is the youngest patient ever reported to have a progressive Enneking stage II C3 GCTB treated with denosumab alone. Denosumab can be administered as a single and conservative therapy for pediatric patients with unresectable upper cervical GCTB, avoiding the risks and morbidity of surgical and radiative treatment.


Assuntos
Denosumab , Tumores de Células Gigantes , Feminino , Humanos , Criança
13.
Glob Chang Biol ; 29(4): 1178-1187, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36371668

RESUMO

Multiple lines of existing evidence suggest that increasing CO2 emission from soils in response to rising temperature could accelerate global warming. However, in experimental studies, the initial positive response of soil heterotrophic respiration (RH ) to warming often weakens over time (referred to apparent thermal acclimation). If the decreased RH is driven by thermal adaptation of soil microbial community, the potential for soil carbon (C) losses would be reduced substantially. In the meanwhile, the response could equally be caused by substrate depletion, and would then reflect the gradual loss of soil C. To address uncertainties regarding the causes of apparent thermal acclimation, we carried out sterilization and inoculation experiments using the soil samples from an alpine meadow with 6 years of warming and nitrogen (N) addition. We demonstrate that substrate depletion, rather than microbial adaptation, determined the response of RH to long-term warming. Furthermore, N addition appeared to alleviate the apparent acclimation of RH to warming. Our study provides strong empirical support for substrate availability being the cause of the apparent acclimation of soil microbial respiration to temperature. Thus, these mechanistic insights could facilitate efforts of biogeochemical modeling to accurately project soil C stocks in the future climate.


Assuntos
Microbiologia do Solo , Solo , Processos Heterotróficos , Aquecimento Global , Aclimatação , Temperatura , Carbono , Respiração
14.
Glob Chang Biol ; 29(12): 3476-3488, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36931867

RESUMO

Root exudates are an important pathway for plant-microbial interactions and are highly sensitive to climate change. However, how extreme drought affects root exudates and the main components, as well as species-specific differences in response magnitude and direction, are poorly understood. In this study, root exudation rates of total carbon (C) and its components (e.g., sugar, organic acid, and amino acid) were measured under the control and extreme drought treatments (i.e., 70% throughfall reduction) by in situ collection of four tree species with different growth rates in a subtropical forest. We also quantified soil properties, root morphological traits, and mycorrhizal infection rates to examine the driving factors underlying variations in root exudation. Our results showed that extreme drought significantly decreased root exudation rates of total C, sugar, and amino acid by 17.8%, 30.8%, and 35.0%, respectively, but increased root exudation rate of organic acid by 38.6%, which were largely associated with drought-induced changes in tree growth rates, root morphological traits, and mycorrhizal infection rates. Specifically, trees with relatively high growth rates were more responsive to drought for root exudation rates compared with those with relatively low growth rates, which were closely related to root morphological traits and mycorrhizal infection rates. These findings highlight the importance of plant growth strategy in mediating drought-induced changes in root exudation rates. The coordinations among root exudation rates, root morphological traits, and mycorrhizal symbioses in response to drought could be incorporated into land surface models to improve the prediction of climate change impacts on rhizosphere C dynamics in forest ecosystems.


Assuntos
Ecossistema , Micorrizas , Raízes de Plantas/metabolismo , Secas , Florestas , Micorrizas/metabolismo , Árvores , Exsudatos e Transudatos/metabolismo , Compostos Orgânicos/análise , Aminoácidos/análise , Aminoácidos/metabolismo , Solo/química , Açúcares/análise , Açúcares/metabolismo , Exsudatos de Plantas/análise , Exsudatos de Plantas/metabolismo
15.
Eur Phys J E Soft Matter ; 46(6): 44, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37306829

RESUMO

Multiphase flows through reservoir rocks are a universal and complex phenomenon. Relative permeability is one of the primary determinants in reservoir performance calculations. Accurate estimation of the relative permeability is crucial for reservoir management and future production. In this paper, we propose inferring relative permeability curves from sparse saturation data with an ensemble Kalman method. We represent these curves through a series of positive increments of relative permeability at specified saturation values, which guarantees monotonicity within, and boundedness between 0 and 1. The proposed method is validated by the inference performances in two synthetic benchmarks designed by SPE and a field-scale model developed by Equinor that includes certain real field features. The results indicate that the relative permeability curves can be accurately estimated within the saturation intervals having available observations and appropriately extrapolated to the remaining saturations by virtue of the embedded constraints. The predicted well responses are comparable to the ground truths, even though they are not included as the observation. The study demonstrates the feasibility of using ensemble Kalman method to infer relative permeability curves from saturation data, which can aid in the predictions of multiphase flow and reservoir production.

16.
Acta Radiol ; 64(7): 2327-2333, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36683329

RESUMO

A hemorrhagic aortopulmonary artery sheath (HAPS) is an infrequent and critical complication of aortic dissection (AD), which is caused by a hematoma extending through the ruptured aortic wall into the aortopulmonary artery sheath. The adventitial hematoma might narrow or even occlude the lumen of the pulmonary arteries and extend into the pulmonary interstitium and alveoli. The prompt and accurate recognition of HAPS on computed tomography (CT) is crucial and might assist in the diagnosis of unidentifiable AD. HAPS was manifested as high attenuation areas surrounded the pulmonary arteries without enhancement on CT; even thickened bronchovascular sheath and ground-glass consolidations surrounded bronchovascular distribution, which might be associated with the prognosis. Aggressive and effective surgical treatment is the primary determinant of short-term survival.


Assuntos
Dissecção Aórtica , Humanos , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Aorta , Artéria Pulmonar/diagnóstico por imagem , Hematoma/complicações , Hematoma/diagnóstico por imagem
17.
Acta Radiol ; 64(1): 80-89, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34928725

RESUMO

BACKGROUND: Myocardial extracellular volume fraction (ECV) assessment can be affected by various technical and subject-related factors. PURPOSE: To evaluate the role of contour-based registration in quantification of ECV and investigate normal segment-based myocardial ECV values at 3T. MATERIAL AND METHODS: Pre- and post-contrast T1 mapping images of the left ventricular basal, mid-cavity, and apical slices were obtained in 26 healthy volunteers. ECV maps were generated using motion correction with and without contour-based registration. The image quality of all ECV maps was evaluated by a 4-point scale. Slices were dichotomized according to the occurrence of misregistration in the source data. Contour-registered ECVs and standard ECVs were compared within each subgroup using analysis of variance for repeated measurements and generalized linear mixed models. RESULTS: In all three slices, higher quality of ECV maps were found using contour-registered method than using standard method. Standard ECVs were statistically different from contour-registered ECVs in global (26.8% ± 2.8% vs. 25.8% ± 2.4%; P = 0.001), mid-cavity (25.4% ± 3.1% vs. 24.3% ± 2.5%; P = 0.016), and apical slices (28.7% ± 4.1% vs. 27.2% ± 3.4%; P = 0.010). In the misregistration subgroups, contour-registered ECVs were lower with smaller SDs (basal: 25.2% ± 1.8% vs. 26.7% ± 2.6%; P = 0.038; mid-cavity: 24.4% ± 2.3% vs. 26.8% ± 3.1%; P = 0.012; apical: 27.5% ± 3.6% vs. 29.7% ± 4.5%; P = 0.016). Apical (27.2% ± 3.4%) and basal-septal ECVs (25.6% ± 2.6%) were statistically higher than mid-cavity ECV (24.3% ± 2.5%; both P < 0.001). CONCLUSION: Contour-based registration can optimize image quality and improve the precision of ECV quantification in cases demonstrating ventricular misregistration among source images.


Assuntos
Meios de Contraste , Miocárdio , Humanos , Valor Preditivo dos Testes , Imageamento por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/métodos
18.
Eur Spine J ; 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38043127

RESUMO

PURPOSE: To explore degeneration and fatty infiltration (FI) of lumbar paraspinal muscles in patients with dynamic sagittal imbalance (DSI) and the relationship between lumbar paraspinal muscles degeneration, fatty infiltration and severity of the disease. METHODS: We recruited 41 DSI patients and selected 22 lumbar spinal stenosis (LSS) patients without osphyalgia as controls. All patients received magnetic resonance imaging (MRI) scan and DSI patients also received pre-walk and post-walk X-rays. DSI patients were divided into 2 subgroups according to their symptom improvement after conservative treatment. We calculated rmCSA and FI of the lumbar paraspinal muscles. The rmCSA and FI between DSI and control and between DSI subgroups were compared by t test. The regression analysis was used to explore the risk factors influencing disease severity. Receiver operating characteristic (ROC) curves and area under curves (AUCs) were used to evaluate the severity of the disease. RESULTS: In comparison of rmCSA and FI between DSI and control, there are significant differences of most muscles. In comparison of rmCSA between two subgroups, there are significant differences of most muscles, while in comparison of FI, only muscles in L4 segment have significant different. In logistic regression analysis, total rmCSA and total FI are risk factors influencing disease severity. ROC curves shows that total rmCSA and total FI both achieve an AUC greater than 0.7. CONCLUSION: Compared with control, DSI patients have degeneration and fatty infiltration of the lumbar paraspinal muscles. The degeneration and fatty infiltration are risk factors influencing disease severity. The total rmCSA and total FI can be used as an indicator to determine whether a patient has severe DSI.

19.
Ecol Lett ; 25(11): 2489-2499, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36134698

RESUMO

Microbial thermal adaptation is considered to be one of the core mechanisms affecting soil carbon cycling. However, the role of microbial community composition in controlling thermal adaptation is poorly understood. Using microbial communities from the rhizosphere and bulk soils in an 8-year warming experiment as a model, we experimentally demonstrate that respiratory thermal adaptation was much stronger in microbial K-strategist-dominated bulk soils than in microbial r-strategist-dominated rhizosphere soils. Soil carbon availability exerted strong selection on the dominant ecological strategy of the microbial community, indirectly influencing respiratory thermal adaptation. Our findings shed light on the linchpin of the dominant ecological strategy exhibited by the microbial community in determining its respiratory thermal adaptation, with implications for understanding soil carbon losses under warming.


Assuntos
Ciclo do Carbono , Microbiologia do Solo , Rizosfera , Solo , Carbono
20.
Plant Physiol ; 185(4): 1682-1696, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893814

RESUMO

Increasing sea levels associated with climate change threaten the survival of coastal forests, yet the mechanisms by which seawater exposure causes tree death remain poorly understood. Despite the potentially crucial role of nonstructural carbohydrate (NSC) reserves in tree survival, their dynamics in the process of death under seawater exposure are unknown. Here we monitored progressive tree mortality and associated NSC storage in Sitka-spruce (Picea sitchensis) trees dying under ecosystem-scale increases in seawater exposure in western Washington, USA. All trees exposed to seawater, because of monthly tidal intrusion, experienced declining crown foliage during the sampling period, and individuals with a lower percentage of live foliated crown (PLFC) died faster. Tree PLFC was strongly correlated with subsurface salinity and needle ion contents. Total NSC concentrations in trees declined remarkably with crown decline, and reached extremely low levels at tree death (2.4% and 1.6% in leaves and branches, respectively, and 0.4% in stems and roots). Starch in all tissues was almost completely consumed, while sugars remained at a homeostatic level in foliage. The decreasing NSC with closer proximity to death and near zero starch at death are evidences that carbon starvation occurred during Sitka-spruce mortality during seawater exposure. Our results highlight the importance of carbon storage as an indicator of tree mortality risks under seawater exposure.


Assuntos
Metabolismo dos Carboidratos , Carboidratos/análise , Picea/química , Picea/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Estresse Salino , Água do Mar/efeitos adversos , Causas de Morte , Salinidade , Washington
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