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1.
Nat Commun ; 15(1): 2851, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565546

RESUMO

Metal-support electronic interactions play crucial roles in triggering the hydrogen spillover (HSo) to boost hydrogen evolution reaction (HER). It requires the supported metal of electron-rich state to facilitate the proton adsorption/spillover. However, this electron-rich metal state contradicts the traditional metal→support electron transfer protocol and is not compatible with the electron-donating oxygen evolution reaction (OER), especially in proton-poor alkaline conditions. Here we profile an Ir/NiPS3 support structure to study the Ir electronic states and performances in HSo/OER-integrated alkaline water electrolysis. The supported Ir is evidenced with Janus electron-rich and electron-poor states at the tip and interface regions to respectively facilitate the HSo and OER processes. Resultantly, the water electrolysis (WE) is efficiently implemented with 1.51 V at 10 mA cm-2 for 1000 h in 1 M KOH and 1.44 V in urea-KOH electrolyte. This research clarifies the Janus electronic state as fundamental in rationalizing efficient metal-support WE catalysts.

2.
Psychiatry Res ; 336: 115894, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38598946

RESUMO

Social determinants of health (SDoH) have been linked to a higher likelihood of experiencing mental health problems. This study aimed to investigate whether the accumulation of unfavorable SDoH is associated with depression symptom. Data was gathered from a representative population participating in the U.S. National Health and Nutrition Examination Survey spanning from 2005 to 2018. Self-reported SDoH were operationalized according to the criteria outlined in Healthy People 2030, with a cumulative measure of unfavorable SDoH calculated for analysis. The presence of depression symptom was identified using the Patient Health Questionnaire in a representative sample of 30,762 participants (49.2 % males) representing 1,392 million non-institutionalized U.S. adults, with 2,675 (8.7 %) participants showing depression symptom. Unfavorable SDoH were found to be significantly and independently associated with depression symptom. Individuals facing multiple unfavorable SDoHs were more likely to experience depression symptom (P for trend < 0.001). For instance, a positive association was observed in participants exposed to six or more unfavorable SDoHs with depression symptom (AOR = 3.537, 95 % CI: 1.781, 7.075, P-value < 0.001). The findings emphasize that the likelihood of developing depression symptom significantly increases when multiple SDoHs are present, compared to just a single SDoH.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38602345

RESUMO

BACKGROUND AND AIM: Linked color imaging (LCI) is an image-enhanced endoscopy technique that accentuates the color difference between red and white, potentially improving the adenoma detection rate (ADR). However, it remains unclear whether LCI performance in detecting colorectal lesions differs based on endoscopists' experience levels. We aimed to evaluate the differences in LCI efficacy based on the experience levels of endoscopists by conducting an exploratory analysis. METHODS: In this post hoc analysis of an international randomized controlled trial comparing the detection of adenoma and other lesions using colonoscopy with LCI and high-definition white light imaging (WLI), we included patients from 11 institutions across four countries/regions: Japan, Thailand, Taiwan, and Singapore. We retrospectively reviewed differences in the lesion detection of LCI according to endoscopists' colonoscopy history or ADR. RESULTS: We included 1692 and 1138 patients who underwent colonoscopies performed by 54 experts (experience of ≥ 5000 colonoscopies) and by 43 non-experts (experience of < 5000 colonoscopies), respectively. Both expert and non-expert groups showed a significant improvement in ADR with LCI compared to WLI (expert, 61.7% vs 46.4%; P < 0.001; non-expert, 56.6% vs 46.4%; P < 0.001). LCI had no effect on sessile serrated lesion detection rate in non-experts (3.1% vs 2.5%; P = 0.518). LCI significantly improved detection rates in endoscopists with relatively low detection performance, defined as an ADR < 50%. CONCLUSIONS: This exploratory study analyzed data from a previous trial and revealed that LCI is useful for both experts and non-experts and is even more beneficial for endoscopists with relatively low detection performance using WLI.

4.
Mol Cancer Ther ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592383

RESUMO

Aurora kinase inhibitors such as alisertib can destabilize MYC-family oncoproteins and have demonstrated compelling anti-tumor efficacy. In this study, we report 6K465, a novel pyrimidine-based Aurora A (AURKA) inhibitor that reduces levels of c-MYC and N-MYC oncoproteins more potently than alisertib. In an analysis of the antiproliferative effect of 6K465, the sensitivities of small cell lung cancer (SCLC) and breast cancer (BC) cell lines to 6K465 were strongly associated with the protein levels of c-MYC and/or N-MYC. We also report DBPR728, an acyl-based prodrug of 6K465 bearing fewer hydrogen-bond donors that exhibited 10-fold improved oral bioavailability. DBPR728 induced durable tumor regression of c-MYC- and/or N-MYC- overexpressing xenografts including SCLC, triple-negative breast cancer (TNBC), hepatocellular carcinoma and medulloblastoma using a 5-on-2-off or once-a-week dosing regimen on a 21-day cycle. A single oral dose of DBPR728 at 300 mg/kg induced c-MYC reduction and cell apoptosis in the tumor xenografts for more than 7 days. The inhibitory effect of DBPR728 at a reduced dosing frequency was attributed to its uniquely high tumor/plasma ratio (3.6-fold within 7 days) and the long tumor half-life of active moiety 6K465. Furthermore, DBPR728 was found to synergize with the mTOR inhibitor everolimus to suppress c-MYC- or N-MYC- driven SCLC. Collectively, these results suggest DBPR728 has the potential to treat cancers overexpressing c-MYC- and/or N-MYC.

6.
Fish Shellfish Immunol ; 149: 109550, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38593891

RESUMO

Signal transducing adapter molecule 2 (STAM2), a member of the Signal Transducing Adapter Molecule (STAM) family, is a protein with significant implications in diverse signaling pathways and endocytic membrane trafficking. However, the role of the STAM2, especially in fish, remains largely unknown. In this study, we discovered that STAM2 negatively regulates the NF-κB signaling pathway, and its inhibitory effect is enhanced upon LPS induction. Our study confirmed that STAM2 can enhance the degradation of myeloid differentiation primary-response protein 88 (MyD88), an upstream regulator of NF-κB pathway. Furthermore, the UIM domain of STAM2 is important for the inhibition of MyD88. Mechanistically, STAM2 inhibits the NF-κB signaling pathway by targeting the MyD88 autophagy pathway. In addition, we showed that STAM2 promotes the proliferation of Vibrio harveyi. In summary, our study reveals that STAM2 inhibits NF-κB signaling activation and mediates innate immunity in teleost via the autophagy pathway.

7.
Zhongguo Zhong Yao Za Zhi ; 49(3): 728-734, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621876

RESUMO

Mesona chinensis is a common medicinal and edible plant in the Lingnan region of China, which has extensive pharmacological activity. However, the study of its chemical constituents is not sufficient. In this study, a variety of modern chromatographic separation techniques were used to isolate two compounds from 95% ethanol extract of the grass parts of M. chinensis. Their absolute configurations were determined by ultraviolet spectroscopy(UV), infrared spectroscopy(IR), high resolution mass spectrometry(HR-ESI-MS), 1D and 2D nuclear magnetic resonance(1D NMR and 2D NMR), and single-crystal X-ray diffraction(SC-XRD). Specifically, they were two new benzoyl-sesquiterpenes and named mesonanol A and mesonanol B, respectively. The results of the pharmacological activity evaluation showed that neither of the two new compounds showed obvious antiviral and anti-inflammatory activities.


Assuntos
Lamiaceae , Sesquiterpenos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho , Estrutura Molecular
8.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1255-1259, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621972

RESUMO

The components with hypoglycemic activity in Plumeria rubra were isolated and purified by various column chromatography techniques and activity tracing methods. The physical and chemical properties of all the purified monomer compounds were characterized and analyzed, and a total of six compounds were isolated and identified, including 6″-acetyl-6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside(1), 6-acetyl-6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside-(1→6″)-ß-D-glucoside(2), 2-hydroxy-6-methoxy-benzyl-benzoate-2-O-ß-D-glucoside(3), 6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside(4), 6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside-(1→6″)-ß-D-glucoside(5), and 6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside-(1→6″)-ß-D-xyloside(6). Compounds 1 and 2 were new compounds, and compounds 3-6 were isolated from Plumeria for the first time. The α-glucosidase inhibitory activity of six identified compounds was tested. The results show that compounds 1-6 show certain inhibitory activity with an IC_(50) value ranging from 8.2 to 33.5 µmol·L~(-1).


Assuntos
Apocynaceae , Glucosídeos , Glucosídeos/química , Benzoatos
9.
Eur J Med Chem ; 270: 116358, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38574638

RESUMO

The fatty acid-binding protein 1 (FABP1) is a fatty acid transporter protein that is considered as an emerging target for metabolic diseases. Despite forceful evidence that the inhibition of FABP1 is essential for ameliorating NASH, pharmacological control and validation of FABP1 are hindered by a lack of relevant inhibitors as pharmacological tool. Therefore, the development of effective FABP1 inhibitors is a current focus of research. Herein, we firstly reported the comprehensive structure-activity relationship (SAR) study of novel FABP1 inhibitors derived from high throughput screening of our in-house library, which resulting in the identification of the optimal compound 44 (IC50 = 4.46 ± 0.54 µM). Molecular docking studies revealed that 44 forms stable hydrogen bonds with amino acids around the active pocket of FABP1. Moreover, 44 alleviated the typical histological features of fatty liver in NASH mice, including steatosis, lobular inflammation, ballooning and fibrosis. Additionally, 44 has been demonstrated to have lipid metabolism regulating, anti-oxidative stress and hepatoprotective properties. This study might be provided a promising insight into the field of NASH and inspiration for the development of FABP1 inhibitors.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Simulação de Acoplamento Molecular , Metabolismo dos Lipídeos , Fibrose , Proteínas de Ligação a Ácido Graxo/metabolismo , Fígado/metabolismo
10.
Head Neck ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572629

RESUMO

BACKGROUND: Oncocytic carcinoma of the thyroid (OCA) is an independent type of thyroid cancer. Radioactive iodine (RAI) therapy was frequently administered to OCA patients, but its contribution to improving survival is indefinite. METHODS: 4641 OCA patients from 2000 to 2018 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Cox proportional hazard regression and competing risk analysis were applied. RESULTS: Tumor size, SEER stage, primary surgery, and neck dissection were prognostic factors for cancer-specific survival. The results of competing risk analysis demonstrated that age over 55 years dramatically increased non-OCA death risks. Treatments that improve non-OCA survival (including total thyroidectomy, RAI therapy, and systemic therapy) should be recommended in OCA patients older than 55 years of age. Neck lymphadenectomy should not be recommended for OCA, since the metastatic lymph node ratio was low (about 3%). CONCLUSIONS: RAI therapy can improve survival in OCA by reducing noncancer death risks.

11.
Lab Invest ; : 102057, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582455

RESUMO

Ovarian carcinoma is usually diagnosed at an advanced stage with peritoneal dissemination and/or lymph node metastasis, and the prognosis for such advanced carcinoma is very poor. Therefore, new biomarkers to predict patient prognosis are needed. Miyamoto et al. previously showed that keratan sulfate (KS) detected by the 5D4 monoclonal antibody was expressed in ovarian carcinoma. However, the detailed structure of such KS was not determined, and the biological significance of this finding remained to be clarified. We previously generated the 297-11A monoclonal antibody, which recognizes galactose (Gal)-6-O-sulfated N-acetyllactosamine (LacNAc) located at the non-reducing terminus. Since the 297-11A epitope overlaps with that of 5D4, here we chose to use the 297-11A antibody as a tool to analyze KS and related structures. We conducted immunohistochemical analysis of 98 ovarian carcinoma cases with 297-11A antibody combined with a series of glycosidases and performed mass spectrometry analysis of the human serous ovarian carcinoma cell line OVCAR-3 to deduce the glycan structure of 297-11A-sulfated glycans. We also performed western blot analysis to assess a potential association of 297-11A-sulfated glycans with the mucin core protein mucin 16 (MUC16; also known as cancer antigen 125 (CA125)). Finally, we examined the relationship between 297-11A expression and patient prognosis. Consequently, 297-11A-sulfated glycans were primarily expressed in serous and endometrioid carcinomas and poorly expressed in mucinous and clear cell carcinomas. We reveal that structurally, 297-11A-sulfated glycans expressed in ovarian carcinoma are O-glycans carrying partially sialylated, Gal-6-O-sulfated LacNAc and that these glycans are likely displayed on MUC16 mucin core proteins. Of clinical importance is that expression of 297-11A-sulfated glycans correlated with shorter progression-free survival in patients. Thus, 297-11A-sulfated glycans may serve as a predictor of ovarian carcinoma recurrence.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38653811

RESUMO

OBJECTIVE: Patient with carotid blowout syndrome (CBS) may demonstrated non-bleeding digital subtraction angiography (DSA) without identifying pseudoaneurysm or contrast extravasation. Our objective is to evaluate the clinical outcomes for this specific subset of patients. MATERIALS AND METHODS: A retrospective observational study was conducted on 172 CBS patients who received DSA for evaluation of transarterial embolization (TAE) between 2005 and 2022, of whom 19 patients had non-bleeding DSA and did not undergo TAE. RESULTS: The age (55.2 ± 7.3 vs. 54.8 ± 11.1), male sex (17/19 vs. 135/153), tumor size (5.6 ± 2.4 vs. 5.2 ± 2.2), cancer locations were similar (P > 0.05) between both groups; except for there were more pseudoaneurysm/active bleeding (85.6% vs. 0%) and less vascular irregularity (14.4% vs. 94.7%) in the TAE group (P < 0.001). In the multivariable Cox regression model adjusting for age, sex, and tumor size, non-bleeding DSA group was independently associated with recurrent bleeding compared to TAE group (adjusted hazard ratio = 3.5, 95% confidence interval: 1.9-6.4, P < 0.001). Furthermore, the presence of vascular irregularity was associated with segmental recurrent bleeding (adjusted HR = 8.0, 95% CI 2.7-23.3, P < 0.001). CONCLUSION: Patient showing non-bleeding DSA thus not having TAE had higher risk of recurrent bleeding, compared to patient who received TAE. Level of Evidence Level 4, Case Series.

13.
J Sci Food Agric ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591367

RESUMO

BACKGROUND: Goat milk is considered a nutritionally superior resource, owing to its advantageous nutritional attributes. Nevertheless, it is susceptible to spoilage and the persistence of pathogens. Electron beam irradiation stands as a promising non-thermal processing technique capable of prolonging shelf life with minimal residue and a high degree of automation. RESULTS: The effects of electron beam irradiation (2, 3, 5, and 7 kGy) on microorganisms, physicochemical properties, and protein structure of goat milk compared with conventional pasteurized goat milk (PGM) was evaluated. It was found that a 2 kGy electron beam irradiation reduces the total microbial count of goat milk by 6-logs, and the irradiated goat milk protein secondary structure showed a significant decrease in ɑ-helix content. Low irradiation doses led to microaggregation and crosslinking. In contrast, high doses (≥ 5 kGy) slightly disrupted the aggregates and decreased the particle size, disrupting the microscopic surface structure of goat milk, verified by scanning electron microscopy and confocal laser scanning microscopy. CONCLUSION: The irradiation of goat milk with a 2 kGy electron beam may effectively inactivate harmful microorganisms in the milk and maintain/or improve the physicochemical quality and protein structure of goat milk compared to thermal pasteurization. © 2024 Society of Chemical Industry.

14.
Crit Care ; 28(1): 118, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594772

RESUMO

BACKGROUND: This study aimed to develop an automated method to measure the gray-white matter ratio (GWR) from brain computed tomography (CT) scans of patients with out-of-hospital cardiac arrest (OHCA) and assess its significance in predicting early-stage neurological outcomes. METHODS: Patients with OHCA who underwent brain CT imaging within 12 h of return of spontaneous circulation were enrolled in this retrospective study. The primary outcome endpoint measure was a favorable neurological outcome, defined as cerebral performance category 1 or 2 at hospital discharge. We proposed an automated method comprising image registration, K-means segmentation, segmentation refinement, and GWR calculation to measure the GWR for each CT scan. The K-means segmentation and segmentation refinement was employed to refine the segmentations within regions of interest (ROIs), consequently enhancing GWR calculation accuracy through more precise segmentations. RESULTS: Overall, 443 patients were divided into derivation N=265, 60% and validation N=178, 40% sets, based on age and sex. The ROI Hounsfield unit values derived from the automated method showed a strong correlation with those obtained from the manual method. Regarding outcome prediction, the automated method significantly outperformed the manual method in GWR calculation (AUC 0.79 vs. 0.70) across the entire dataset. The automated method also demonstrated superior performance across sensitivity, specificity, and positive and negative predictive values using the cutoff value determined from the derivation set. Moreover, GWR was an independent predictor of outcomes in logistic regression analysis. Incorporating the GWR with other clinical and resuscitation variables significantly enhanced the performance of prediction models compared to those without the GWR. CONCLUSIONS: Automated measurement of the GWR from non-contrast brain CT images offers valuable insights for predicting neurological outcomes during the early post-cardiac arrest period.


Assuntos
Parada Cardíaca Extra-Hospitalar , Substância Branca , Humanos , Estudos Retrospectivos , Substância Cinzenta/diagnóstico por imagem , Parada Cardíaca Extra-Hospitalar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Prognóstico
15.
Sci Transl Med ; 16(743): eadk5395, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630847

RESUMO

Endoscopy is the primary modality for detecting asymptomatic esophageal squamous cell carcinoma (ESCC) and precancerous lesions. Improving detection rate remains challenging. We developed a system based on deep convolutional neural networks (CNNs) for detecting esophageal cancer and precancerous lesions [high-risk esophageal lesions (HrELs)] and validated its efficacy in improving HrEL detection rate in clinical practice (trial registration ChiCTR2100044126 at www.chictr.org.cn). Between April 2021 and March 2022, 3117 patients ≥50 years old were consecutively recruited from Taizhou Hospital, Zhejiang Province, and randomly assigned 1:1 to an experimental group (CNN-assisted endoscopy) or a control group (unassisted endoscopy) based on block randomization. The primary endpoint was the HrEL detection rate. In the intention-to-treat population, the HrEL detection rate [28 of 1556 (1.8%)] was significantly higher in the experimental group than in the control group [14 of 1561 (0.9%), P = 0.029], and the experimental group detection rate was twice that of the control group. Similar findings were observed between the experimental and control groups [28 of 1524 (1.9%) versus 13 of 1534 (0.9%), respectively; P = 0.021]. The system's sensitivity, specificity, and accuracy for detecting HrELs were 89.7, 98.5, and 98.2%, respectively. No adverse events occurred. The proposed system thus improved HrEL detection rate during endoscopy and was safe. Deep learning assistance may enhance early diagnosis and treatment of esophageal cancer and may become a useful tool for esophageal cancer screening.


Assuntos
Aprendizado Profundo , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Lesões Pré-Cancerosas , Humanos , Pessoa de Meia-Idade , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Estudos Prospectivos , Lesões Pré-Cancerosas/patologia
16.
Brain Commun ; 6(2): fcae086, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638152

RESUMO

Tau, a hallmark of Alzheimer's disease, is poorly characterized in cerebral amyloid angiopathy. We aimed to assess the clinico-radiological correlations between tau positron emission tomography scans and cerebral amyloid angiopathy. We assessed cerebral amyloid and hyperphosphorylated tau in patients with probable cerebral amyloid angiopathy (n = 31) and hypertensive small vessel disease (n = 27) using 11C-Pittsburgh compound B and 18F-T807 positron emission tomography. Multivariable regression models were employed to assess radio-clinical features related to cerebral tau pathology in cerebral amyloid angiopathy. Cerebral amyloid angiopathy exhibited a higher cerebral tau burden in the inferior temporal lobe [1.25 (1.17-1.42) versus 1.08 (1.05-1.22), P < 0.001] and all Braak stage regions of interest (P < 0.05) than hypertensive small vessel disease, although the differences were attenuated after age adjustment. Cerebral tau pathology was significantly associated with cerebral amyloid angiopathy-related vascular markers, including cortical superficial siderosis (ß = 0.12, 95% confidence interval 0.04-0.21) and cerebral amyloid angiopathy score (ß = 0.12, 95% confidence interval 0.03-0.21) after adjustment for age, ApoE4 status and whole cortex amyloid load. Tau pathology correlated significantly with cognitive score (Spearman's ρ=-0.56, P = 0.001) and hippocampal volume (-0.49, P = 0.007), even after adjustment. In conclusion, tau pathology is more frequent in sporadic cerebral amyloid angiopathy than in hypertensive small vessel disease. Cerebral amyloid angiopathy-related vascular pathologies, especially cortical superficial siderosis, are potential markers of cerebral tau pathology suggestive of concomitant Alzheimer's disease.

18.
Materials (Basel) ; 17(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38612128

RESUMO

This study focuses on using activated fly ash to preparate silica aerogel by the acid solution-alkali leaching method and ambient pressure drying. Additionally, to improve the performance of silica aerogel, C6H16O3Si (KH-570) and CH3Si(CH3O)3 (MTMS) modifiers were used. Finally, this paper investigated the factors affecting the desilication rate of fly ash and analyzed the structure and performance of silica aerogel. The experimental results show that: (1) The factors affecting the desilication rate are ranked as follows: hydrochloric acid concentration > solid-liquid ratio > reaction temperature > reaction time. (2) KH-570 showed the best performance, and when the volume ratio of the silica solution to it was 10:1, the density of silica aerogel reached a minimum of 183 mg/cm3. (3) The optimal process conditions are a hydrochloric acid concentration of 20 wt%, a solid-liquid ratio of 1:4, a reaction time of two hours, and a reaction temperature of 100 °C. (4) The optimal performance parameters of silica aerogel were the thermal conductivity, specific surface area, pore volume, average pore size, and contact angle values, with 0.0421 W·(m·K)-1, 487.9 m2·g-1, 1.107 cm3·g-1, 9.075 nm, and 123°, respectively. This study not only achieves the high-value utilization of fly ash, but also facilitates the effective recovery and utilization of industrial waste.

19.
Glob Chang Biol ; 30(4): e17274, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605677

RESUMO

Climate change and other anthropogenic disturbances are increasing liana abundance and biomass in many tropical and subtropical forests. While the effects of living lianas on species diversity, ecosystem carbon, and nutrient dynamics are receiving increasing attention, the role of dead lianas in forest ecosystems has been little studied and is poorly understood. Trees and lianas coexist as the major woody components of forests worldwide, but they have very different ecological strategies, with lianas relying on trees for mechanical support. Consequently, trees and lianas have evolved highly divergent stem, leaf, and root traits. Here we show that this trait divergence is likely to persist after death, into the afterlives of these organs, leading to divergent effects on forest biogeochemistry. We introduce a conceptual framework combining horizontal, vertical, and time dimensions for the effects of liana proliferation and liana tissue decomposition on ecosystem carbon and nutrient cycling. We propose a series of empirical studies comparing traits between lianas and trees to answer questions concerning the influence of trait afterlives on the decomposability of liana and tree organs. Such studies will increase our understanding of the contribution of lianas to terrestrial biogeochemical cycling, and help predict the effects of their increasing abundance.


Assuntos
Ecossistema , Clima Tropical , Florestas , Árvores , Carbono
20.
Cell Stem Cell ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38608707

RESUMO

Autonomic parasympathetic neurons (parasymNs) control unconscious body responses, including "rest-and-digest." ParasymN innervation is important for organ development, and parasymN dysfunction is a hallmark of autonomic neuropathy. However, parasymN function and dysfunction in humans are vastly understudied due to the lack of a model system. Human pluripotent stem cell (hPSC)-derived neurons can fill this void as a versatile platform. Here, we developed a differentiation paradigm detailing the derivation of functional human parasymNs from Schwann cell progenitors. We employ these neurons (1) to assess human autonomic nervous system (ANS) development, (2) to model neuropathy in the genetic disorder familial dysautonomia (FD), (3) to show parasymN dysfunction during SARS-CoV-2 infection, (4) to model the autoimmune disease Sjögren's syndrome (SS), and (5) to show that parasymNs innervate white adipocytes (WATs) during development and promote WAT maturation. Our model system could become instrumental for future disease modeling and drug discovery studies, as well as for human developmental studies.

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