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1.
Annu Rev Neurosci ; 47(1): 323-344, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38648267

RESUMO

Since its recent discovery, the meningeal lymphatic system has reshaped our understanding of central nervous system (CNS) fluid exchange, waste clearance, immune cell trafficking, and immune privilege. Meningeal lymphatics have also been demonstrated to functionally modify the outcome of neurological disorders and their responses to treatment, including brain tumors, inflammatory diseases such as multiple sclerosis, CNS injuries, and neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review, we discuss recent evidence of the contribution of meningeal lymphatics to neurological diseases, as well as the available experimental methods for manipulating meningeal lymphatics in these conditions. Finally, we also provide a discussion of the pressing questions and challenges in utilizing meningeal lymphatics as a prime target for CNS therapeutic intervention and possibly drug delivery for brain disorders.


Assuntos
Doenças do Sistema Nervoso Central , Meninges , Humanos , Animais , Doenças do Sistema Nervoso Central/fisiopatologia , Doenças do Sistema Nervoso Central/patologia , Sistema Linfático/fisiologia , Sistema Linfático/fisiopatologia , Vasos Linfáticos/fisiologia
2.
Immunity ; 56(9): 2070-2085.e11, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37557168

RESUMO

Lymph nodes (LNs) are critical sites for shaping tissue-specific adaptive immunity. However, the impact of LN sharing between multiple organs on such tailoring is less understood. Here, we describe the drainage hierarchy of the pancreas, liver, and the upper small intestine (duodenum) into three murine LNs. Migratory dendritic cells (migDCs), key in instructing adaptive immune outcome, exhibited stronger pro-inflammatory signatures when originating from the pancreas or liver than from the duodenum. Qualitatively different migDC mixing in each shared LN influenced pancreatic ß-cell-reactive T cells to acquire gut-homing and tolerogenic phenotypes proportional to duodenal co-drainage. However, duodenal viral infections rendered non-intestinal migDCs and ß-cell-reactive T cells more pro-inflammatory in all shared LNs, resulting in elevated pancreatic islet lymphocyte infiltration. Our study uncovers immune crosstalk through LN co-drainage as a powerful force regulating pancreatic autoimmunity.


Assuntos
Autoimunidade , Pâncreas , Camundongos , Animais , Pâncreas/patologia , Fígado , Linfócitos T , Linfonodos
3.
Proc Natl Acad Sci U S A ; 121(6): e2307072120, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38300864

RESUMO

Amplified warming of high latitudes and rapid thaw of frozen ground threaten permafrost carbon stocks. The presence of permafrost modulates water infiltration and flow, as well as sediment transport, on soil-mantled slopes, influencing the balance of advective fluvial processes to diffusive processes on hillslopes in ways that are different from temperate settings. These processes that shape permafrost landscapes also impact the carbon stored on soil-mantled hillslopes via temperature, saturation, and slope stability such that carbon stocks and landscape morphometry should be closely linked. We studied [Formula: see text]69,000 headwater basins between 25° and 90 °N to determine whether the thermal state of the soil sets the balance between hillslope (diffusive) and fluvial (advective) erosion processes, as evidenced by the density of the channel networks (i.e., drainage density) and the proportion of convex to concave topography (hillslopes and river valleys, respectively). Watersheds within permafrost regions have lower drainage densities than regions without permafrost, regardless of watershed glacial history, mean annual precipitation, and relief. We find evidence that advective fluvial processes are inhibited in permafrost landscapes compared to their temperate counterparts. Frozen soils likely inhibit channel development, and we predict that climate warming will lower incision thresholds to promote growth of the channel network in permafrost landscapes. By demonstrating how the balance of advective versus diffusive processes might shift with future warming, we gain insight into the mechanisms that shift these landscapes from sequestering to exporting carbon.

4.
Proc Natl Acad Sci U S A ; 120(41): e2308941120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782785

RESUMO

Impaired lymphatic drainage and lymphedema are major morbidities whose mechanisms have remained obscure. To study lymphatic drainage and its impairment, we engineered a microfluidic culture model of lymphatic vessels draining interstitial fluid. This lymphatic drainage-on-chip revealed that inflammatory cytokines that are known to disrupt blood vessel junctions instead tightened lymphatic cell-cell junctions and impeded lymphatic drainage. This opposing response was further demonstrated when inhibition of rho-associated protein kinase (ROCK) was found to normalize fluid drainage under cytokine challenge by simultaneously loosening lymphatic junctions and tightening blood vessel junctions. Studies also revealed a previously undescribed shift in ROCK isoforms in lymphatic endothelial cells, wherein a ROCK2/junctional adhesion molecule-A (JAM-A) complex emerges that is responsible for the cytokine-induced lymphatic junction zippering. To validate these in vitro findings, we further demonstrated in a genetic mouse model that lymphatic-specific knockout of ROCK2 reversed lymphedema in vivo. These studies provide a unique platform to generate interstitial fluid pressure and measure the drainage of interstitial fluid into lymphatics and reveal a previously unappreciated ROCK2-mediated mechanism in regulating lymphatic drainage.


Assuntos
Molécula A de Adesão Juncional , Vasos Linfáticos , Linfedema , Quinases Associadas a rho , Animais , Camundongos , Biomimética , Citocinas/metabolismo , Células Endoteliais/metabolismo , Junções Intercelulares , Molécula A de Adesão Juncional/metabolismo , Vasos Linfáticos/metabolismo , Linfedema/genética , Linfedema/metabolismo , Quinases Associadas a rho/metabolismo
5.
Cell Mol Life Sci ; 81(1): 275, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907858

RESUMO

While conventional cancer modalities, such as chemotherapy and radiotherapy, act through direct killing of tumor cells, cancer immunotherapy elicits potent anti-tumor immune responses thereby eliminating tumors. Nevertheless, promising outcomes have not been reported in patients with glioblastoma (GBM) likely due to the immune privileged status of the central nervous system and immunosuppressive micro-environment within GBM. In the past years, several exciting findings, such as the re-discovery of meningeal lymphatic vessels (MLVs), three-dimensional anatomical reconstruction of MLV networks, and the demonstration of the promotion of GBM immunosurveillance by lymphatic drainage enhancement, have revealed an intricate communication between the nervous and immune systems, and brought hope for the development of new GBM treatment. Based on conceptual framework of the updated cancer-immunity (CI) cycle, here we focus on GBM antigen drainage and immune activation, the early events in driving the CI cycle. We also discuss the implications of these findings for developing new therapeutic approaches in tackling fatal GBM in the future.


Assuntos
Antígenos de Neoplasias , Neoplasias Encefálicas , Glioblastoma , Imunoterapia , Humanos , Glioblastoma/imunologia , Glioblastoma/terapia , Glioblastoma/patologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Animais , Microambiente Tumoral/imunologia , Vasos Linfáticos/imunologia , Vasos Linfáticos/patologia
6.
Small ; : e2307079, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700056

RESUMO

Siphon is an effective method to transfer liquid from a higher to a lower level, which has many applications in hygienic design, clinical apparatus, and hydraulic engineering. Traditional operation requires energy to overcome gravity and establish flow in a closed system. Achieving sustainable high flux siphon drainage without energy input remains a challenge due to viscous dissipation. Here, an unexpected open siphon behavior on the South American pitcher plant Heliamphora minor consisting of trichomes covered pitcher and a wedge-shaped sheath is examined. Exploiting the concept of Digital Twin, a new biomimetic research method by transforming the biological sample to a virtual 3D model is proposed and unveiled that maintained connection of wicking on sub-millimeter long trichomes due to asymmetric pressure distribution and ascending in wedge sheath under unbalanced pressure forms continuous surface flow. Exploring this mechanism, a biomimetic siphon device achieving continuous high flux exposed to ambient air is constructed. Besides, particles floating on the meniscus in the outside wedge move under a curvature gradient as water ascends, which implies a biological nutrient capture method and new dust collection manner in the drainage system. Applying the underlying principle enhances the siphon efficiency of floor drains and has the potential for other liquid transfer device design improvements.

7.
Small ; : e2404002, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39194487

RESUMO

The recovery of rare earth elements (REEs) from acidic wastewater is crucial to sustainable development, industrial processes, and human health. In this research, ß-cyclodextrin-based nanosponges (ß-CD/PVA-SA NSs) have been proposed as potential adsorbents for europium (Eu), dysprosium (Dy), and gadolinium (Gd) recovery. The nanosponges are synthesized by cross-linking ß-cyclodextrin (ß-CD) functionalized polyvinyl alcohol (PVA) and sodium alginate (SA). Experimental results indicate that ß-CD/PVA-SA NSs exhibit favorable selectivity for Eu, Dy, and Gd, with the maximum adsorption capacity of 222, 217, and 204 mg/g, respectively, in addition to stability and cyclicity. ß-CD/PVA-SA NSs maintain selective adsorption effects towards RE ions that are present in acidic mine drainage (AMD), thereby highlighting their potential for practical applications. Furthermore, density functional theory (DFT) simulations have unveiled the fundamental interactions between the functional groups anchored in ß-CD/PVA-SA NSs and the REEs, providing vital insights into their adsorption mechanism. Hence, the utilization of ß-CD/PVA-SA NSs has the potential to advance initiatives in remediating acidic water pollution and facilitating the sustainable recycling of RE resources.

8.
J Neurosci Res ; 102(1): e25267, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284855

RESUMO

The central nervous system has long been thought to lack a clearance system similar to the peripheral lymphatic system. Therefore, the clearance of metabolic waste in the central nervous system has been a subject of great interest in neuroscience. Recently, the cerebral lymphatic drainage system, including the parenchymal clearance system and the meningeal lymphatic network, has attracted considerable attention. It has been extensively studied in various neurological disorders. Solute accumulation and neuroinflammation after epilepsy impair the blood-brain barrier, affecting the exchange and clearance between cerebrospinal fluid and interstitial fluid. Restoring their normal function may improve the prognosis of epilepsy. However, few studies have focused on providing a comprehensive overview of the brain clearance system and its significance in epilepsy. Therefore, this review addressed the structural composition, functions, and methods used to assess the cerebral lymphatic system, as well as the neglected association with epilepsy, and provided a theoretical basis for therapeutic approaches in epilepsy.


Assuntos
Epilepsia , Humanos , Sistema Linfático , Sistema Nervoso Central , Encéfalo , Barreira Hematoencefálica
9.
Appl Environ Microbiol ; 90(3): e0198723, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38391193

RESUMO

Streams impacted by historic mining activity are characterized by acidic pH, unique microbial communities, and abundant metal-oxide precipitation, all of which can influence groundwater-surface water exchange. We investigate how metal-oxide precipitates and hyporheic mixing mediate the composition of microbial communities in two streams receiving acid-rock and mine drainage near Silverton, Colorado, USA. A large, neutral pH hyporheic zone facilitated the precipitation of metal particles/colloids in hyporheic porewaters. A small, low pH hyporheic zone, limited by the presence of a low-permeability, iron-oxyhydroxide layer known as ferricrete, led to the formation of steep geochemical gradients and high dissolved-metal concentrations. To determine how these two hyporheic systems influence microbiome composition, we installed well clusters and deployed in situ microcosms in each stream to sample porewaters and sediments for 16S rRNA gene sequencing. Results indicated that distinct hydrogeochemical conditions were present above and below the ferricrete in the low pH system. A positive feedback loop may be present in the low pH stream where microbially mediated precipitation of iron-oxides contributes to additional clogging of hyporheic pore spaces, separating abundant, iron-oxidizing bacteria (Gallionella spp.) above the ferricrete from rare, low-abundance bacteria below the ferricrete. Metal precipitates and colloids that formed in the neutral pH hyporheic zone were associated with a more diverse phylogenetic community of nonmotile, nutrient-cycling bacteria that may be transported through hyporheic pore spaces. In summary, biogeochemical conditions influence, and are influenced by, hyporheic mixing, which mediates the distribution of micro-organisms and, thus, the cycling of metals in streams receiving acid-rock and mine drainage. IMPORTANCE: In streams receiving acid-rock and mine drainage, the abundant precipitation of iron minerals can alter how groundwater and surface water mix along streams (in what is known as the "hyporheic zone") and may shape the distribution of microbial communities. The findings presented here suggest that neutral pH streams with large, well-mixed hyporheic zones may harbor and transport diverse microorganisms attached to particles/colloids through hyporheic pore spaces. In acidic streams where metal oxides clog pore spaces and limit hyporheic exchange, iron-oxidizing bacteria may dominate and phylogenetic diversity becomes low. The abundance of iron-oxidizing bacteria in acid mine drainage streams has the potential to contribute to additional clogging of hyporheic pore spaces and the accumulation of toxic metals in the hyporheic zone. This research highlights the dynamic interplay between hydrology, geochemistry, and microbiology at the groundwater-surface water interface of acid mine drainage streams.


Assuntos
Ferro , Microbiota , Filogenia , RNA Ribossômico 16S/genética , Óxidos , Metais , Bactérias/genética , Água/química , Coloides
10.
BMC Microbiol ; 24(1): 305, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148068

RESUMO

BACKGROUND: Phylogeographic studies have gained prominence in linking past geological events to the distribution patterns of biodiversity, primarily in mountainous regions. However, such studies often focus on plant taxa, neglecting the intricate biogeographical patterns of microbes, particularly soil microbial communities. This article explores the spatial distribution of the nematode-trapping fungus Arthrobotrys oligospora, a widespread microorganism, in a tectonically active region at the southeastern edge of the Qinghai-Tibetan Plateau. By analysing the genetic variation of this fungus alongside the historical structure of major river watersheds, we sought to uncover potential connections between the two. Our study involved sampling 149 strains from 116 sites across six major watersheds in the region. RESULTS: The resulting haplotype network revealed five distinct clusters, each corresponding closely to a specific watershed. These clusters exhibited high haplotype diversity and low nucleotide diversity, supporting the notion of watershed-based segregation. Further analysis of haplotypes shared across watersheds provided evidence for three proposed past river connections. In particular, we found numerous shared haplotypes between the Yangtze and Mekong basins, as well as between the Yangtze and the Red basins. Evidence for a Irrawaddy-Salween-Red and a Yangtze-Pearl-Red river connections were also portrayed in our mapping exercise. CONCLUSIONS: These findings emphasize the crucial role of historical geomorphological events in shaping the biogeography of microbial biodiversity, alongside contemporary biotic and abiotic factors. Watershed perimeters emerged as effective predictors of such patterns, suggesting their suitability as analytical units for regional-scale studies. Our study also demonstrates the potential of microorganisms and phylogeographic approaches to complement traditional geological analyses, providing a more comprehensive understanding of past landscape structure and its evolution.


Assuntos
Variação Genética , Haplótipos , Filogenia , Filogeografia , Rios , Microbiologia do Solo , China , Rios/microbiologia , Ascomicetos/genética , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Biodiversidade , DNA Fúngico/genética
11.
Ophthalmology ; 131(3): 266-276, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37769852

RESUMO

PURPOSE: To compare the effectiveness and safety of the MicroShunt (Santen Inc) versus trabeculectomy in patients with primary open-angle glaucoma (POAG). DESIGN: Prospective, randomized, multicenter trial conducted in the United States and Europe. PARTICIPANTS: Adult patients (aged 40-85 years) with mild to severe POAG inadequately controlled on maximum tolerated medical therapy and intraocular pressure (IOP) ≥ 15 mmHg and ≤ 40 mmHg. METHODS: Patients were randomized 3:1 to stand-alone MicroShunt implantation (n = 395) or trabeculectomy (n = 132), both augmented with mitomycin C (MMC) 0.2 mg/ml for 2 minutes. MAIN OUTCOME MEASURES: The primary effectiveness end point was surgical success, defined as ≥ 20% reduction in mean diurnal IOP from baseline with no increase in glaucoma medications. Secondary end points included changes in mean IOP and medication use from baseline and the need for postoperative interventions. RESULTS: At 2 years, the rate of surgical success was lower in the MicroShunt group than in the trabeculectomy group (50.6% vs. 64.4%, P = 0.005). Mean diurnal IOP was reduced from 21.1 ± 4.9 mmHg at baseline to 13.9 ± 3.9 mmHg at 24 months in the MicroShunt group and from 21.1 ± 5.0 mmHg at baseline to 10.7 ± 3.7 mmHg at 24 months in the trabeculectomy group (P < 0.001 compared with baseline in both groups). Mean medication use decreased from 3.1 to 0.9 in the MicroShunt group and from 2.9 to 0.4 in the trabeculectomy group (P < 0.001 compared with baseline in both groups). Adverse events at 2 years were generally similar in the 2 groups, except that hypotony was more common in eyes undergoing trabeculectomy (51.1% vs. 30.9%, P < 0.001). Repositioning or explantation of the implant occurred in 6.8% of MicroShunt patients. The majority of these patients had device removal at the time of subsequent glaucoma surgery. Vision-threatening complications were uncommon in both groups. CONCLUSION: At 2 years, both the MicroShunt and trabeculectomy provided significant reductions in IOP and medication use, with trabeculectomy continuing to have greater surgical success. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Trabeculectomia , Adulto , Humanos , Glaucoma/cirurgia , Glaucoma de Ângulo Aberto/cirurgia , Glaucoma de Ângulo Aberto/tratamento farmacológico , Pressão Intraocular , Mitomicina , Estudos Prospectivos , Trabeculectomia/métodos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
12.
J Vasc Surg ; 80(2): 586-594.e5, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636609

RESUMO

OBJECTIVE: This study aimed to investigate the incidence of cerebrospinal fluid drainage (CSFD)-related complications specifically in patients who underwent fenestrated and branched endovascular aortic repair (F/B-EVAR). This objective was chosen considering the limitations and uncertainties surrounding its efficacy in preventing spinal cord injury. METHODS: A systematic review following Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted (PROSPERO; #CRD42022359223). Literature searches of MEDLINE, Embase, and Scopus were performed until May 1, 2023, focusing on studies published after January 1, 2000. The inclusion criteria encompassed studies reporting on F/B-EVAR, CSFD, and drain-related complications. Data extraction and quality assessment using the Newcastle-Ottawa Scale were performed by multiple reviewers to ensure accuracy and reliability. A proportion meta-analysis was conducted to calculate the pooled rate and 95% confidence interval (CI). The primary and secondary outcomes were CSFD-related mortality and morbidity, respectively. RESULTS: Six retrospective, observational, single-center studies were included, totaling 1079 patients and 730 CSFD placements (all prophylactic except for one). The Newcastle-Ottawa Scale showed a high to moderate risk of bias. The analysis revealed a CSFD-related mortality rate of 1.4% (95% CI: 0.0-4.8; I2 = 67.7%) and an overall morbidity rate of 25.6% (95% CI: 13.6-39.7; I2 = 83.2%). The overall major, moderate, and minor estimated complication rates were 6.1% (95% CI: 4.1-8.5; I2 = 0%), 4.6% (95% CI: 2.4-7.3; I2 = 33.5%), and 26.4% (95% CI: 16.5-37.7; I2 = 84.9%), respectively. Severe complications included intracranial hemorrhage (2.8%), spinal hematoma (1.4%), subarachnoid hemorrhage (1.4%), and CSFD-related neurological deficits (1.1%). A pooled estimate of 11.4% for nonfunctioning drainage was found. CONCLUSIONS: F/B-EVAR patients showed a notable incidence of CSFD-related death and substantial morbidity. This study highlights the limitations of the available data, the high prevalence of complications associated with CSFD, and the need for further research to better understand the risks and benefits of CSFD in F/B-EVAR. This calls for careful consideration regarding the routine use of prophylactic drainage due to the accumulating evidence of the risks associated with CSFD without proven benefit in this specific context.


Assuntos
Implante de Prótese Vascular , Drenagem , Procedimentos Endovasculares , Humanos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Drenagem/efeitos adversos , Drenagem/mortalidade , Drenagem/instrumentação , Fatores de Risco , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Resultado do Tratamento , Medição de Risco , Feminino , Masculino , Idoso , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/epidemiologia , Correção Endovascular de Aneurisma
13.
Glob Chang Biol ; 30(1): e16972, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37882506

RESUMO

Mosses of the genus Sphagnum are the dominant vegetation in most pristine peatlands in temperate and high-latitude regions. They play a crucial role in carbon sequestration, being responsible for ca. 50% of carbon accumulation through their active participation in peat formation. They have a significant influence on the dynamics of CO2 emissions due to an efficient maximum potential photosynthetic rate, lower respiration rates, and the production of a recalcitrant litter whose decomposition is gradual. However, various anthropogenic disturbances and land use management actions that favor its reestablishment have the potential to modify the dynamics of these CO2 emissions. Therefore, the objective of this review is to discuss the role of Sphagnum in CO2 emissions generated in peatland ecosystems, and to understand the impacts of anthropogenic practices favorable and detrimental to Sphagnum on these emissions. Based on our review, increased Sphagnum cover reduces CO2 emissions and fosters C sequestration, but drainage transforms peatlands dominated by Sphagnum into a persistent source of CO2 due to lower gross primary productivity of the moss and increased respiration rates. Sites with moss removal used as donor material for peatland restoration emit twice as much CO2 as adjacent undisturbed natural sites, and those with commercial Sphagnum extraction generate almost neutral CO2 emissions, yet both can recover their sink status in the short term. The reintroduction of fragments and natural recolonization of Sphagnum in transitional peatlands, can reduce emissions, recover, or increase the CO2 sink function in the short and medium term. Furthermore, Sphagnum paludiculture is seen as a sustainable alternative for the use of transitional peatlands, allowing moss production strips to become CO2 sink, however, it is necessary to quantify the emissions of all the components of the field of production (ditches, causeway), and the biomass harvested from the moss to establish a final closing balance of C.


Assuntos
Ecossistema , Sphagnopsida , Dióxido de Carbono/análise , Áreas Alagadas , Solo
14.
Glob Chang Biol ; 30(3): e17246, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38501699

RESUMO

Northern peatlands provide a globally important carbon (C) store. Since the beginning of the 20th century, however, large areas of natural peatlands have been drained for biomass production across Fennoscandia. Today, drained peatland forests constitute a common feature of the managed boreal landscape, yet their ecosystem C balance and associated climate impact are not well understood, particularly within the nutrient-poor boreal region. In this study, we estimated the net ecosystem carbon balance (NECB) from a nutrient-poor drained peatland forest and an adjacent natural mire in northern Sweden by integrating terrestrial carbon dioxide (CO2 ) and methane (CH4 ) fluxes with aquatic losses of dissolved organic C (DOC) and inorganic C based on eddy covariance and stream discharge measurements, respectively, over two hydrological years. Since the forest included a dense spruce-birch area and a sparse pine area, we were able to further evaluate the effect of contrasting forest structure on the NECB and component fluxes. We found that the drained peatland forest was a net C sink with a 2-year mean NECB of -115 ± 5 g C m-2 year-1 while the adjacent mire was close to C neutral with 14.6 ± 1.7 g C m-2 year-1 . The NECB of the drained peatland forest was dominated by the net CO2 exchange (net ecosystem exchange [NEE]), whereas NEE and DOC export fluxes contributed equally to the mire NECB. We further found that the C sink strength in the sparse pine forest area (-153 ± 8 g C m-2 year-1 ) was about 1.5 times as high as in the dense spruce-birch forest area (-95 ± 8 g C m-2 year-1 ) due to enhanced C uptake by ground vegetation and lower DOC export. Our study suggests that historically drained peatland forests in nutrient-poor boreal regions may provide a significant net ecosystem C sink and associated climate benefits.


Assuntos
Sequestro de Carbono , Ecossistema , Dióxido de Carbono/análise , Suécia , Solo/química , Florestas , Metano/análise
15.
Glob Chang Biol ; 30(9): e17495, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39235092

RESUMO

Drained wetlands are thought to be carbon (C) source hotspots, and rewetting is advocated to restore C storage in drained wetlands for climate change mitigation. However, current assessments of wetland C balance mainly focus on vertical fluxes between the land and atmosphere, frequently neglecting lateral carbon fluxes and land-use effects. Here, we conduct a global synthesis of 893 annual net ecosystem C balance (NECB) measures that include net ecosystem exchange of CO2, along with C input via manure fertilization, and C removal through biomass harvest or hydrological exports of dissolved organic and inorganic carbon, across wetlands of different status and land uses. We find that elevating water table substantially reduces net ecosystem C losses, with the annual NECB decreasing from 2579 (95% interval: 1976 to 3214) kg C ha-1 year-1 in drained wetlands to -422 (-658 to -176) kg C ha-1 year-1 in natural wetlands, and to -934 (-1532 to -399) kg C ha-1 year-1 in rewetted wetlands globally. Climate, land-use history, and time since water table changes introduce variabilities, with drainage for (sub)tropical agriculture or forestry uses showing high annual C losses, while the net C losses from drained wetlands can continue to affect soil C pools for several decades. Rewetting all types of drained wetlands is needed, particularly for those formerly agriculture-used (sub)tropical wetlands where net ecosystem C losses can be largely reduced. Our findings suggest that elevating water table is an important initiative to reduce C losses in degraded wetlands, which could contribute to policy decisions for managing wetlands to enhance their C sequestration.


Assuntos
Ciclo do Carbono , Mudança Climática , Áreas Alagadas , Carbono/análise , Carbono/metabolismo , Água Subterrânea/química , Água Subterrânea/análise , Agricultura/métodos , Biomassa , Ecossistema , Sequestro de Carbono
16.
BMC Cancer ; 24(1): 263, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402391

RESUMO

BACKGROUND: Whether Transanal drainage tubes (TDTs) placement reduces the occurrence of anastomotic leakage (AL) after rectal cancer (RC) surgery remains controversial. Most existing meta-analyses rely on retrospective studies, while the prospective studies present an inadequate level of evidence. METHODS: A systematic review and meta-analysis of prospective studies on TDTs placement in RC patients after surgery was conducted. The main analysis index was the incidence of AL, Grade B AL, and Grade C AL, while secondary analysis index was the incidence of anastomotic bleeding, incision infection, and anastomotic stenosis. A comprehensive literature search was performed utilizing the databases Cochrane Library, Embase, PubMed, and Web of Science. We recorded Risk ratios (RRs) and 95% confidence intervals (CI) for each included study, and a fixed-effect model or random-effect model was used to investigate the correlation between TDTs placement and four outcomes after RC surgery. RESULTS: Seven studies (1774 participants, TDT 890 vs non-TDT 884) were considered eligible for quantitative synthesis and meta-analysis. The meta-analysis revealed that the incidence of AL was 9.3% (83/890) in the TDT group and 10.2% (90/884) in the non-TDT group. These disparities were found to lack statistical significance (P = 0.58). A comprehensive meta-analysis, comprising four studies involving a cumulative sample size of 1259 participants, revealed no discernible disparity in the occurrence of Grade B AL or Grade C AL between the TDT group and the non-TDT group (Grade B AL: TDT 34/631 vs non-TDT 26/628, P = 0.30; Grade C AL: TDT 11/631 vs non-TDT 27/628, P = 0.30). Similarly, the incidences of anastomotic bleeding (4 studies, 876 participants), incision infection (3studies, 713 participants), and anastomotic stenosis (2studies, 561 participants) were 5.5% (24/440), 8.1% (29/360), and 2.9% (8/280), respectively, in the TDT group, and 3.0% (13/436), 6.5% (23/353), and 3.9% (11/281), respectively, in the non-TDT group. These differences were also determined to lack statistical significance (P = 0.08, P = 0.43, P = 0.48, respectively). CONCLUSION: The placement of TDTs does not significantly affect the occurrence of AL, Grade B AL, and Grade C AL following surgery for rectal cancer. Additionally, TDTs placement does not be associated with increased complications such as anastomotic bleeding, incision infection, or anastomotic stenosis. TRIAL REGISTRATION: PROSPERO: CRD42023427914.


Assuntos
Fístula Anastomótica , Drenagem , Neoplasias Retais , Humanos , Fístula Anastomótica/etiologia , Fístula Anastomótica/epidemiologia , Neoplasias Retais/cirurgia , Incidência , Drenagem/métodos , Canal Anal/cirurgia
17.
Gastrointest Endosc ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038522

RESUMO

BACKGROUND AND AIMS: Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is an effective biliary drainage technique for patients with altered anatomy or duodenal strictures. Endoscopic ultrasound-guided hepaticojejunostomy (EUS-HJS) can be used to create a fistula between the left hepatic duct and the jejunum in patients with a history of total gastrectomy. No specific data on this technique have been published. The aim of this study was to assess the feasibility and safety of EUS-HJS in patients with a history of total gastrectomy. METHODS: This retrospective multicenter study included all adult patients who underwent EUS-HJS at three tertiary French centers and one tertiary Swiss center between May 2011 and February 2023. The primary outcome was clinical success, which was defined as the disappearance of pruritus, jaundice and/or cholangitis. An improvement in bilirubin greater than 30% within the first week and/or bilirubin normalization within 1 month after the procedure were also considered indicators of clinical success. Secondary outcomes included technical success, the rate of adverse events, the need for endoscopic revision, the possibility of resuming anticancer treatment, median survival, and technical differences compared to EUS-HGS. RESULTS: A total of 21 patients who underwent complete gastrectomy via EUS-HJS were included. Technical success was achieved in 100% of patients (95% CI 85%-100%). Clinical success was achieved in 80% of patients (95% CI 58%-92%). The incidence of recorded adverse events was 33% (95% CI 17%-55%), with cholangitis being the most frequent complication. Seven patients (39%) were able to benefit from anticancer treatment after the procedure. The median survival was 6 months (IQR 1.5-12). CONCLUSION: EUS-HJS is an effective and feasible procedure for patients whose anatomy has been altered by total gastrectomy.

18.
Mol Cell Biochem ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294731

RESUMO

Subdural hematoma (SDH) drains into the extracranial lymphatic system through the meningeal lymphatic vessels (mLVs) but the formation of SDH impairs mLVs. Because vitamin D (Vit D) can protect the endothelial cells, we hypothesized that Vit D may enhance the SDH clearance. SDH was induced in Sprague-Dawley rats and treated with Vit D or vehicle. Hematoma volume in each group was measured by H&E staining and hemoglobin quantification. Evans blue (EB) quantification and red blood cells injection were used to evaluated the drainage of mLVs. Western blot analysis and immunofluorescence were conducted to assess the expression of lymphatic protein markers. We also examined the inflammatory factors levels in subdural space by ELISA. Vit D treatment significantly reduced SDH volume and improved the drainage of SDH to cervical lymph nodes. The structure of mLVs in SDH rats were protected by Vit D, and the expressions of LYVE1, PROX1, FOXC2, and VE-cadherin were increased after Vit D treatment. The TNF-α, IL-6, and IL-8 levels were reduced in Vit D group. In vitro, Vit D also increased the VE-cadherin expression levels under inflammation. Vit D protects the structure of mLVs and enhances the absorption of SDH, partly by the anti-inflammatory effect of Vit D.

19.
Am J Obstet Gynecol ; 230(3S): S1046-S1060.e1, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38462248

RESUMO

The third stage of labor is defined as the time period between delivery of the fetus through delivery of the placenta. During a normal third stage, uterine contractions lead to separation and expulsion of the placenta from the uterus. Postpartum hemorrhage is a relatively common complication of the third stage of labor. Strategies have been studied to mitigate the risk of postpartum hemorrhage, leading to the widespread implementation of active management of the third stage of labor. Initially, active management of the third stage of labor consisted of a bundle of interventions including administration of a uterotonic agent, early cord clamping, controlled cord traction, and external uterine massage. However, the effectiveness of these interventions as a bundle has been questioned, leading to abandonment of some components in recent years. Despite this, upon review of selected international guidelines, we found that the term "active management of the third stage of labor" was still used, but recommendations for and against individual interventions were variable and not necessarily supported by current evidence. In this review, we: (1) examine the physiology of the third stage of labor, (2) present evidence related to interventions that prevent postpartum hemorrhage and promote maternal and neonatal health, (3) review current global guidelines and recommendations for practice, and (4) propose future areas of investigation. The interventions in this review include pharmacologic agents to prevent postpartum hemorrhage, cord clamping, cord milking, cord traction, cord drainage, early skin-to-skin contact, and nipple stimulation. Treatment of complications of the third stage of labor is outside of the scope of this review. We conclude that current evidence supports the use of effective pharmacologic postpartum hemorrhage prophylaxis, delayed cord clamping, early skin-to-skin contact, and controlled cord traction at delivery when feasible. The most effective uterotonic regimens for preventing postpartum hemorrhage after vaginal delivery include oxytocin plus ergometrine; oxytocin plus misoprostol; or carbetocin. After cesarean delivery, carbetocin or oxytocin as a bolus are the most effective regimens. There is inconsistent evidence regarding the use of tranexamic acid in addition to a uterotonic compared with a uterotonic alone for postpartum hemorrhage prevention after all deliveries. Because of differences in patient comorbidities, costs, and availability of resources and staff, decisions to use specific prevention strategies are dependent on patient- and system-level factors. We recommend that the term "active management of the third stage of labor" as a combined intervention no longer be used. Instead, we recommend that "third stage care" be adopted, which promotes the implementation of evidence-based interventions that incorporate practices that are safe and beneficial for both the woman and neonate.


Assuntos
Trabalho de Parto , Ocitócicos , Hemorragia Pós-Parto , Gravidez , Feminino , Recém-Nascido , Humanos , Hemorragia Pós-Parto/induzido quimicamente , Ocitocina/uso terapêutico , Ocitócicos/uso terapêutico , Prática Clínica Baseada em Evidências
20.
World J Urol ; 42(1): 147, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478082

RESUMO

OBJECTIVE: We aimed to assess the impact of the timing of urinary drainage on clinical outcomes in patients with obstructive pyelonephritis (OPN) associated with upper urinary tract (UUT) stones. METHODS: We retrospectively evaluated the multicenter dataset of 240 patients with OPN associated with UUT stones who underwent urinary drainage. We divided the patients into two groups depending on the timing of urinary drainage; emergency drainage, defined as within 12 h from admission, and delayed drainage, defined as between 12 and 48 h from admission. The outcomes were the length of hospital stay, time to leukocyte normalization, and time to body temperature normalization. One-to-two propensity score matching (PSM) was applied to minimize the effect of confounders between the two groups. Subsequently, predictive patient factors for emergency drainage were analyzed using the logistic regression model. RESULTS: Only the time from admission to normal body temperature was significantly shorter in the emergency drainage group when compared with the delayed drainage group (median: 2 vs. 3 days; p = 0.02), while there was no difference in time from drainage to body temperature normalization between the two groups. On multivariable analysis, high pretreatment C-reactive protein (CRP) was associated with implementing emergency drainage within 12 h. CONCLUSIONS: The timing of urinary drainage was only associated with the duration of high fever, but it did not affect the postdrainage course. Emergency urinary drainage is more likely to be performed in severe patients, such as high pretreatment CRP.


Assuntos
Pielonefrite , Cálculos Urinários , Sistema Urinário , Humanos , Drenagem , Pontuação de Propensão , Pielonefrite/complicações , Estudos Retrospectivos , Cálculos Urinários/complicações , Estudos Multicêntricos como Assunto
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