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1.
J Environ Manage ; 368: 122126, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39116809

RESUMEN

Soil respiration (RS) is crucial for releasing carbon dioxide (CO2) from terrestrial ecosystems to atmosphere. Prescribed burning (a common forest management tool), along with its important by-product pyrogenic carbon (PyC), can influence the carbon cycle of forest soil. However, few studies explore RS and PyC spatial correlation after prescribed burning. In this study, we investigated the spatial pattern of RS and its influencing factors by conducting prescribed burnings in a temperate artificial Pinus koraiensis forest. RS was measured 1 day (1 d) pre-prescribed burning, 1 d, 1 year (1 yr) and two years (2 yr) after prescribed burning. Significant decrease in RS were observed 1-2 yr After burning (reductions of 65.2% and 41.7% respectively). The spatial autocorrelation range of RS decreased pre-burning (2.72m), then increased post-burning (1 d: 2.44m; 1 yr: 40.14m; 2 yr: 9.8m), indicating a more homogeneous distribution of patch reduction. Pyrogenic carbon (PyC) in the soil gradually decreased in the short term after burning with reductions of 19%, 52%, and 49% (1d., 1 yr And 2 yr After the fire, respectively). However, PyC and RS exhibited a strong spatial positive correlation from 1 d.- 1 yr post-burning. The spatial regression model of dissolved organic carbon (DOC) on RS demonstrated significant positive spatial correlation in all measurements (pre- and post-burning). Microbial carbon to soil nitrogen ratio (MCN) notably influenced RS pre-burning and 1-2 yr post-burning. RS also showed significant spatial correlation in cross-variance with NH4+-N and NO3--N post-burning. The renewal of the PyC positively influenced RS, subsequently affecting its spatial distribution in 1d.- 1yr. Introducing PyC into RS studies helps enhances understanding of prescribed fire effects on forest soil carbon (C) pools, and provides valuable information regarding regional or ecosystem C cycling, facilitating a more accurate prediction of post-burning changes in forest soil C pools.

2.
J Natl Compr Canc Netw ; : 1-7, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39074497

RESUMEN

BACKGROUND: Malignant phyllodes tumors (MPTs) are rare breast tumors with high risks of local recurrence and distant metastasis. Surgical intervention is the primary treatment, but the effectiveness of adjuvant therapies is uncertain. This study was designed to analyze the prognostic risk factors associated with MPTs and evaluate the efficacy of postoperative adjuvant chemotherapy. PATIENTS AND METHODS: Patients who were first diagnosed with MPT without distant metastasis and received R0 resection surgery between 1999 and 2023 were included in the present study and stratified into 2 groups: chemotherapy and nonchemotherapy groups. Propensity score matching (PSM) was used to balance baseline characteristics between groups. Kaplan-Meier curves were used to estimate local recurrence-free survival (LRFS) and overall survival (OS). Cox proportional hazards analyses (univariate and multivariate) were conducted to identify prognostic risk factors. RESULTS: We conducted a study involving 145 patients, 31 of whom underwent a total of 12 different chemotherapy regimens following initial surgical resection. Most patients received chemotherapy regimens primarily consisting of anthracyclines, including anthracycline + ifosfamide (AI) or anthracycline + cyclophosphamide/docetaxel (AC-T) regimens. After a median follow-up of 54.5 months, 37 (25.5%) patients experienced local recurrence and 24 (16.6%) experienced distant metastasis. No significant difference was detected in the rates of local recurrence or distant metastasis between the 2 groups. Axillary lymph node positivity was the only risk factor for LRFS, whereas older age, larger tumors, axillary lymph node positivity, local recurrence, and distant metastasis were significantly associated with worse OS. Chemotherapy did not emerge as a protective factor for LRFS (P=.501) or OS (P=.854). After PSM, patients in the chemotherapy group did not exhibit better 5-year LRFS (P=.934) or 5-year OS (P=.328). CONCLUSIONS: According to our retrospective evaluation, postoperative adjuvant chemotherapy was not associated with improved survival in patients with MPTs without distant metastasis.

3.
bioRxiv ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38712205

RESUMEN

Hypertension and transient increases in blood pressure from extreme exertion are risk factors for aortic dissection in patients with age-related vascular degeneration or inherited connective tissue disorders. Yet, the common experimental model of angiotensin II-induced aortopathy in mice appears independent of high blood pressure as lesions do not occur in response to an alternative vasoconstrictor, norepinephrine, and are not prevented by co-treatment with a vasodilator, hydralazine. We investigated vasoconstrictor administration to adult mice 1 week after disruption of TGFß signaling in smooth muscle cells. Norepinephrine increased blood pressure and induced aortic dissection by 7 days and even within 30 minutes that was rescued by hydralazine; results were similar with angiotensin II. Changes in regulatory contractile molecule expression were not of pathological significance. Rather, reduced synthesis of extracellular matrix yielded a vulnerable aortic phenotype by decreasing medial collagen, most dynamically type XVIII, and impairing cell-matrix adhesion. We conclude that transient and sustained increases in blood pressure cause dissection in aortas rendered vulnerable by inhibition of TGFß-driven extracellular matrix production by smooth muscle cells. A corollary is that medial fibrosis, a frequent feature of medial degeneration, may afford some protection against aortic dissection.

4.
bioRxiv ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38746256

RESUMEN

Smooth muscle cells (SMCs) of cardiac and neural crest origin contribute to the developing proximal aorta and are linked to disease propensity in adults. We analyzed single-cell transcriptomes of SMCs from mature thoracic aortas in mice to determine basal states and changes after disrupting transforming growth factor-ß (TGFß) signaling necessary for aortic homeostasis. A minority of Myh11 lineage-marked SMCs differentially expressed genes suggestive of embryological origin. Additional analyses in Nkx2-5 and Wnt1 lineage-marked SMCs derived from cardiac and neural crest progenitors, respectively, showed both lineages contributed to a major common cluster and each lineage to a minor distinct cluster. Common cluster SMCs extended from root to arch, cardiac subset cluster SMCs from root to mid-ascending, while neural crest subset cluster SMCs were restricted to the arch. The neural crest subset cluster had greater expression of a subgroup of TGFß-dependent genes suggesting specific responsiveness or skewed extracellular matrix synthesis. Nonetheless, deletion of TGFß receptors in SMCs resulted in similar transcriptional changes among all clusters, primarily decreased extracellular matrix molecules and modulators of TGFß signaling. Many embryological markers of murine aortic SMCs were not confirmed in adult human aortas. We conclude: (i) there are multiple subtypes of cardiac- and neural crest-derived SMCs with shared or distinctive transcriptional profiles, (ii) neural crest subset SMCs with increased expression of certain TGFß-inducible genes are not spatially linked to the aortic root predisposed to aneurysms from aberrant TGFß signaling, and (iii) loss of TGFß responses after receptor deletion is uniform among SMCs of different embryological origins.

5.
Chemosphere ; 352: 141295, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309605

RESUMEN

Hierarchically porous magnetic biochar (HMB) had been found to act as an effective amendment to remediate cadmium (Cd) in water and soil in a previous study, but the effects on wheat growth, Cd uptake and translocation mechanisms, and soil microorganisms were unknown. Therefore, soil Cd form transformation, soil enzyme activity, soil microbial diversity, wheat Cd uptake and migration, and wheat growth were explored by adding different amounts of HMB to alkaline Cd-contaminated soil under pot experiments. The results showed that application of HMB (0.5 %-2.0 %) raised soil pH, electrical conductivity (EC) and available Fe concentration, decreased soil available Cd concentration (35.11 %-50.91 %), and promoted Cd conversion to less bioavailable Cd forms. HMB treatments could reduce Cd enrichment in wheat, inhibit Cd migration from root to stem, rachis to glume, glume to grain, and promote Cd migration from stem to leaf and stem to rachis. HMB (0.5 %-1.0 %) boosted antioxidant enzyme activity, reduced oxidative stress, and enhanced photosynthesis in wheat seedlings. Application of 1.0 % HMB increased wheat grain biomass by 40.32 %. Besides, the addition of HMB (0.5 %-1.0 %) could reduce soil Cd bioavailability, increase soil enzyme activity, and increase the abundance and diversity of soil bacteria. Higher soil EC brought forth by HMB (2.0 %) made the wheat plants and soil bacteria poisonous. This study suggests that applying the right amount of HMB to alkaline Cd-contaminated soil could be a potential remediation strategy to decrease Cd in plants' edible parts and enhance soil quality.


Asunto(s)
Microbiota , Contaminantes del Suelo , Cadmio/toxicidad , Cadmio/análisis , Suelo/química , Triticum , Porosidad , Contaminantes del Suelo/análisis , Carbón Orgánico/química , Grano Comestible/química , Antioxidantes/análisis , Fenómenos Magnéticos
6.
BMC Surg ; 24(1): 54, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355536

RESUMEN

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) has an extremely poor prognosis. A previous study proved that low-dose radiotherapy (RT) could prolong the prognosis of HCC patients with PVTT. This study aims to explore the sensitivity of PVTT to RT treatment. METHODS: Patients were selected based on imaging diagnosis of HCC accompanied by PVTT and received combined treatment of radiotherapy, antiangiogenic drugs and immune checkpoint inhibitors, followed by hepatectomy or liver transplantation from January 2019 to August 2022. The efficacy was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST) guidelines and pathological assessment. The sensitivity of tumor cells to the treatment was compared between the primary tumor (PT)and PVTT by analyzing their residual tumor and pathologic complete remission (PCR) incidence. RESULTS: Data from 14 patients were collected in the study. After combined treatment, the size of PVTT decreased more significantly than that of the primary tumor in the imaging study (p < 0.05). The residual cancer was significantly more restrictive than that of primary tumor in paired patients based on pathological measurement (p = 0.008). The PCR incidence of the primary tumor (21.42%) was significantly lower (p = 0.008) than that of PVTT in the pathologic study (78.57%). CONCLUSION: PVTT is more sensitive to radiotherapy treatment than the primary tumor in patients with HCC. This combination therapy might be an effective option as a downstaging therapy for patients with HCC with PVTT.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Trombosis , Humanos , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Vena Porta/patología , Estudios Retrospectivos , Trombosis/patología , Resultado del Tratamiento
7.
Plant Physiol Biochem ; 206: 108199, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38100890

RESUMEN

Cadmium (Cd) contamination is a serious challenge in agricultural soils worldwide, resulting in Cd entering the food chain mainly through plant-based food and threatening human health. Minimizing Cd bioaccumulation in wheat is an important way to prevent Cd hazards to humans. Hydroponic and pot experiments were conducted to comprehensively evaluate the effects of zinc sulfate (ZnSO4) and zinc oxide nanoparticles (nZnO) on Cd uptake, translocation, subcellular distribution, cellular ultrastructure, and gene expression in two wheat genotypes that differ in grain Zn accumulation. Results showed that high-dose nZnO significantly reduced root Cd concentration (52.44%∼56.85%) in two wheats, in contrast to ZnSO4. The S216 exhibited higher tolerance to Cd compared to Z797. Importantly, Zn supplementation enhanced Cd sequestration into vacuoles and binding to cell walls, which conferred stability to ultracellular structures and photosynthetic apparatus. Down-regulation of influx transporter (TaHMA2 and TaLCT1) and up-regulation of efflux transporters (TaTM20 and TaHMA3) in Z797 might contribute to Zn-dependent alleviation of Cd toxicity and enhance its Cd tolerance. Down-regulation of ZIP transporters (TaZIP3, -5, and -7) might contribute to an increase in root Zn concentration and inhibit Cd absorption. Additionally, soil Zn provided an effective strategy for the reduction of grain Cd concentrations in both wheats, with a reduction of 26%∼32% (high ZnSO4) and 11%∼67% (high nZnO), respectively. Collectively, these findings provide new insights and perspectives on the mechanisms of Cd mitigation in wheats with different Zn fertilizers and demonstrate that the effect of nZnO in mitigating Cd stress is greater than that of ZnSO4 fertilizers.


Asunto(s)
Nanopartículas , Contaminantes del Suelo , Óxido de Zinc , Humanos , Óxido de Zinc/farmacología , Cadmio/metabolismo , Zinc/farmacología , Zinc/metabolismo , Triticum/metabolismo , Fertilizantes , Suelo , Proteínas de Transporte de Membrana/metabolismo , Expresión Génica , Contaminantes del Suelo/metabolismo
8.
Biomech Model Mechanobiol ; 23(2): 687-701, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38151614

RESUMEN

Despite its vital importance for establishing proper cardiovascular function, the process through which the vasculature develops and matures postnatally remains poorly understood. From a clinical perspective, an ability to mechanistically model the developmental time course in arteries and veins, as well as to predict how various pathologies and therapeutic interventions alter the affected vessels, promises to improve treatment strategies and long-term clinical outcomes, particularly in pediatric patients suffering from congenital heart defects. In the present study, we conducted a multiscale investigation into the postnatal development of the murine thoracic aorta, examining key allometric relations as well as relationships between in vivo mechanical stresses, collagen and elastin expression, and the gradual accumulation of load-bearing constituents within the aortic wall. Our findings suggest that the production of fibrillar collagens in the developing aorta associates strongly with the ratio of circumferential stresses between systole and diastole, hence emphasizing the importance of a pulsatile mechanobiological stimulus. Moreover, rates of collagen turnover and elastic fiber compaction can be inferred directly by synthesizing transcriptional data and quantitative histological measurements of evolving collagen and elastin content. Consistent with previous studies, we also observed that wall shear stresses acting on the aorta are similar at birth and in maturity, supporting the hypothesis that at least some stress targets are established early in development and maintained thereafter, thus providing a possible homeostatic basis to guide future experiments and inform future predictive modeling.


Asunto(s)
Aorta , Elastina , Recién Nacido , Humanos , Animales , Ratones , Niño , Elastina/metabolismo , Aorta Torácica/patología , Colágeno/metabolismo , Colágenos Fibrilares/metabolismo , Estrés Mecánico
9.
Acta cir. bras ; 34(2): e201900201, 2019. graf
Artículo en Inglés | LILACS | ID: biblio-989059

RESUMEN

Abstract Purpose: To investigated the effects of ginsenoside Rb1 on diabetic retinopathy in streptozotocin-induced diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of streptozotocin (80 mg/kg) in male Wistar rats. Ginsenoside Rb1 (20, 40 mg/kg) was injected (i.p.) once a day for 4 weeks. Then, using fundus photography, the diameter and vascular permeability of retinal vessels were investigated. Retinal histopathology was undertaken. Contents of malondialdehyde (MDA) and glutathione (GSH) in retinas were assayed. Levels of nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione cysteine ligase catalytic subunit (GCLC), and glutathione cysteine ligase modulatory subunit (GCLM) were measured. Results: Treatment with ginsenoside Rb1 attenuated the diabetes-induced increase in the diameter of retinal blood vessels. Ginsenoside Rb1 reduced extravasation of Evans Blue dye from retinal blood vessels. Ginsenoside Rb1 partially inhibited the increase in MDA content and decrease in GSH level in rat retinas. Nrf2 levels in the nuclei of retinal cells and expression of GCLC and GCLM were increased significantly in rats treated with ginsenoside Rb1. Conclusion: These findings suggest that ginsenoside Rb1 can attenuate diabetic retinopathy by regulating the antioxidative function in rat retinas.


Asunto(s)
Animales , Masculino , Ratas , Diabetes Mellitus Experimental/tratamiento farmacológico , Retinopatía Diabética/tratamiento farmacológico , Vasos Retinianos/efectos de los fármacos , Vasos Retinianos/patología , Ratas Wistar , Estreptozocina , Ginsenósidos/uso terapéutico
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