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1.
EClinicalMedicine ; 74: 102736, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091669

RESUMEN

Background: Masked hypertension is associated with target organ damage (TOD) and adverse health outcomes, but whether antihypertensive treatment improves TOD in patients with masked hypertension is unproven. Methods: In this multicentre, randomised, double-blind, placebo-controlled trial at 15 Chinese hospitals, untreated outpatients aged 30-70 years with an office blood pressure (BP) of <140/<90 mm Hg and 24-h, daytime or nighttime ambulatory BP of ≥130/≥80, ≥135/≥85, or ≥120/≥70 mm Hg were enrolled. Patients had ≥1 sign of TOD: electrocardiographic left ventricular hypertrophy (LVH), brachial-ankle pulse wave velocity (baPWV) ≥1400 cm/s, or urinary albumin-to-creatinine ratio (ACR) ≥3.5 mg/mmol in women and ≥2.5 mg/mmol in men. Exclusion criteria included secondary hypertension, diabetic nephropathy, serum creatinine ≥176.8 µmol/L, and cardiovascular disease within 6 months of screening. After stratification for centre, sex and the presence of nighttime hypertension, eligible patients were randomly assigned (1:1) to receive antihypertensive treatment or placebo. Patients and investigators were masked to group assignment. Active treatment consisted of allisartan starting at 80 mg/day, to be increased to 160 mg/day at month 2, and to be combined with amlodipine 2.5 mg/day at month 4, if the ambulatory BP remained uncontrolled. Matching placebos were used likewise in the control group. The primary endpoint was the improvement of TOD, defined as normalisation of baPWV, ACR or LVH or a ≥20% reduction in baPWV or ACR over the 48-week follow-up. The intention-to-treat analysis included all randomised patients, the per-protocol analysis patients who fully adhered to the protocol, and the safety analysis all patients who received at least one dose of the study medication. This study is registered with ClinicalTrials.gov, NCT02893358. Findings: Between February 14, 2017, and October 31, 2020, 320 patients (43.1% women; mean age ± SD 53.7 ± 9.7 years) were enrolled. Baseline office and 24-h BP averaged 130 ± 6.0/81 ± 5.9 mm Hg and 136 ± 8.6/84 ± 6.1 mm Hg, and the prevalence of elevated baPWV, ACR and LVH were 97.5%, 12.5%, and 7.8%, respectively. The 24-h BP decreased on average (±SE) by 10.1 ± 0.9/6.4 ± 0.5 mm Hg in 153 patients on active treatment and by 1.3 ± 0.9/1.0 ± 0.5 mm Hg in 167 patients on placebo. Improvement of TOD occurred in 79 patients randomised to active treatment and in 49 patients on placebo: 51.6% (95% CI 43.7%, 59.5%) versus 29.3% (22.1, 36.5%; p < 0.0001). Per-protocol and subgroup analyses were confirmatory. Adverse events were generally mild and occurred in 38 (25.3%) and 43 (26.4%) patients randomised to active treatment and placebo, respectively (p = 0.83). Interpretation: Our results suggest that antihypertensive treatment improves TOD in patients with masked hypertension, highlighting the need of treatment. However, the long-term benefit in preventing cardiovascular complications still needs to be established. Funding: Salubris China.

2.
J Nanobiotechnology ; 22(1): 460, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090717

RESUMEN

BACKGROUND: Nanoplastics (NPs) are emerging pollutants that pose risks to living organisms. Recent findings have unveiled the reproductive harm caused by polystyrene nanoparticles (PS-NPs) in female animals, yet the intricate mechanism remains incompletely understood. Under this research, we investigated whether sustained exposure to PS-NPs at certain concentrations in vivo can enter oocytes through the zona pellucida or through other routes that affect female reproduction. RESULTS: We show that PS-NPs disrupted ovarian functions and decreased oocyte quality, which may be a contributing factor to lower female fertility in mice. RNA sequencing of mouse ovaries illustrated that the PI3K-AKT signaling pathway emerged as the predominant environmental information processing pathway responding to PS-NPs. Western blotting results of ovaries in vivo and cells in vitro showed that PS-NPs deactivated PI3K-AKT signaling pathway by down-regulating the expression of PI3K and reducing AKT phosphorylation at the protein level, PI3K-AKT signaling pathway which was accompanied by the activation of autophagy and apoptosis and the disruption of steroidogenesis in granulosa cells. Since PS-NPs penetrate granulosa cells but not oocytes, we examined whether PS-NPs indirectly affect oocyte quality through granulosa cells using a granulosa cell-oocyte coculture system. Preincubation of granulosa cells with PS-NPs causes granulosa cell dysfunction, resulting in a decrease in the quality of the cocultured oocytes that can be reversed by the addition of 17ß-estradiol. CONCLUSIONS: This study provides findings on how PS-NPs impact ovarian function and include transcriptome sequencing analysis of ovarian tissue. The study demonstrates that PS-NPs impair oocyte quality by altering the functioning of ovarian granulosa cells. Therefore, it is necessary to focus on the research on the effects of PS-NPs on female reproduction and the related methods that may mitigate their toxicity.


Asunto(s)
Células de la Granulosa , Nanopartículas , Oocitos , Poliestirenos , Transducción de Señal , Animales , Femenino , Ratones , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Fertilidad/efectos de los fármacos , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Nanopartículas/toxicidad , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Ovario/efectos de los fármacos , Ovario/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Poliestirenos/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos
3.
Phytother Res ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39098645

RESUMEN

Inflammatory osteolysis is often caused by the excessive activation of osteoclasts stimulated by bacterial products such as lipopolysaccharide. The natural flavonoid trifolirhizin (TRI) has anti-inflammatory properties; however, its function in inflammatory bone lysis remains unclear. This study aimed to elucidate the potential regulatory mechanisms of TRI in osteoclasts.Tartrate-resistant acid phosphatase (TRAP) staining, acid secretion assays, podosomal actin belt fluorescence staining, and bone resorption assays were used to investigate the effects of TRI on osteoclast differentiation and bone resorption. A reactive oxygen species (ROS) measurement kit was used to detect the effect of TRI on ROS levels in osteoclasts. The effects of TRI on genes and signaling pathways related to osteoclast differentiation were determined by quantitative polymerase chain reaction (qPCR) and western blotting. A mouse model of lipopolysaccharide-mediated inflammatory osteolysis was established, and the effects of TRI treatment on bone mass were observed using micro-CT and histological examination. Mechanistically, TRI reduced ROS production by inhibiting receptor activator of nuclear factor-κB ligand (RANKL)-induced activation of the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, and by upregulating the expression levels of the anti-ROS enzymes heme oxygenase-1 (HO-1) and catalase (CAT), which contributed to the degradation of ROS, ultimately leading to a decrease in osteoclastogenesis. TRI inhibited osteoclast formation and ameliorated lipopolysaccharide (LPS)-mediated inflammatory osteolysis. Thus, TRI may be a candidate agent for anti-inflammatory osteolysis.

4.
Cell Chem Biol ; 31(8): 1394-1404, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39151406

RESUMEN

Voltage-gated sodium (Nav) and calcium (Cav) channels are responsible for the initiation of electrical signals. They have long been targeted for the treatment of various diseases. The mounting number of cryoelectron microscopy (cryo-EM) structures for diverse subtypes of Nav and Cav channels from multiple organisms necessitates a generic residue numbering system to establish the structure-function relationship and to aid rational drug design or optimization. Here we suggest a structure-based residue numbering scheme, centering around the most conserved residues on each of the functional segments. We elaborate the generic numbers through illustrative examples, focusing on representative drug-binding sites of eukaryotic Nav and Cav channels. We also extend the numbering scheme to compare common disease mutations among different Nav subtypes. Application of the generic residue numbering scheme affords immediate insights into hotspots for pathogenic mutations and critical loci for drug binding and will facilitate drug discovery targeting Nav and Cav channels.


Asunto(s)
Canales de Calcio , Humanos , Canales de Calcio/metabolismo , Canales de Calcio/química , Canales de Calcio/genética , Canales de Sodio Activados por Voltaje/química , Canales de Sodio Activados por Voltaje/metabolismo , Canales de Sodio Activados por Voltaje/genética , Animales , Sitios de Unión , Mutación , Microscopía por Crioelectrón , Modelos Moleculares , Secuencia de Aminoácidos
5.
Stress Health ; : e3462, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39154192

RESUMEN

Hair cortisol concentration (HCC) is a valuable biomarker for evaluating chronic stress in preschoolers. However, few studies have explored early life HCC and its associated factors. This prospective cohort study analysed the HCC in children aged 6-48 months and its associations with parental HCC as well as positive and negative parental mental health outcomes. We used data from the ongoing Longitudinal Examination Across Prenatal and Postpartum Health in Taiwan (LEAPP-HIT) project, conducted in Taipei between 2020 and 2024. Hair samples were collected from both parents and children in 177 families (91 samples obtained during pregnancy and 86 during the postpartum period). The parents also completed self-reported questionnaires. Multiple linear regression was conducted to analyse the data. We observed a significant positive correlation between parents' and preschoolers' HCC. Furthermore, maternal depression (adjusted beta coefficient [aß] = 0.09, 95% confidence interval [CI] = 0.02, 0.16) and perceived stress (aß = 0.15, 95% CI = 0.02, 0.26) were positively associated with preschoolers' HCC. By contrast, higher maternal eudaimonia was associated with lower HCC in preschoolers (aß = -0.11, 95% CI = -0.20, -0.01). For parents, maternal depression, anxiety, and perceived stress were independently associated with an increased HCC during the postnatal period, whereas maternal eudaimonia was negatively associated with HCC. Our results indicate that both mothers and fathers affect children's responses to stress. Assessment of cortisol stress hormone concentrations through hair samples can be a key means of detecting preschoolers' stress levels and enabling early intervention.

6.
MedComm (2020) ; 5(9): e685, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39156764

RESUMEN

Chimeric RNAs, distinct from DNA gene fusions, have emerged as promising therapeutic targets with diverse functions in cancer treatment. However, the functional significance and therapeutic potential of most chimeric RNAs remain unclear. Here we identify a novel fusion transcript of solute carrier family 2-member 11 (SLC2A11) and macrophage migration inhibitory factor (MIF). In this study, we investigated the upregulation of SLC2A11-MIF in The Cancer Genome Atlas cohort and a cohort of patients from Sun Yat-Sen Memorial Hospital. Subsequently, functional investigations demonstrated that SLC2A11-MIF enhanced the proliferation, antiapoptotic effects, and metastasis of bladder cancer cells in vitro and in vivo. Mechanistically, the fusion protein encoded by SLC2A11-MIF interacted with polypyrimidine tract binding protein 1 (PTBP1) and regulated the mRNA half-lives of Polo Like Kinase 1, Roundabout guidance receptor 1, and phosphoinositide-3-kinase regulatory subunit 3 in BCa cells. Moreover, PTBP1 knockdown abolished the enhanced impact of SLC2A11-MIF on biological function and mRNA stability. Furthermore, the expression of SLC2A11-MIF mRNA is regulated by CCCTC-binding factor and stabilized through RNA N4-acetylcytidine modification facilitated by N-acetyltransferase 10. Overall, our findings revealed a significant fusion protein orchestrated by the SLC2A11-MIF-PTBP1 axis that governs mRNA stability during the multistep progression of bladder cancer.

7.
Chem Commun (Camb) ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162090

RESUMEN

A metal-free and sustainable visible-light-mediated method for the preparation of organic nitrate esters has been developed through the aerobic nitrooxylation reaction of α-diazoesters and cyclic ethers with t-BuONO in the presence of dioxygen. This protocol provides an efficient approach to access nitrate esters with the advantages of clean energy, broad substrate scope, green oxidants, operational simplicity, and mild conditions.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39103479

RESUMEN

Voltage-gated ion channels (VGICs), including those for Na+, Ca2+ and K+, selectively permeate ions across the cell membrane in response to changes in membrane potential, thus participating in physiological processes involving electrical signalling, such as neurotransmission, muscle contraction and hormone secretion. Aberrant function or dysregulation of VGICs is associated with a diversity of neurological, psychiatric, cardiovascular and muscular disorders, and approximately 10% of FDA-approved drugs directly target VGICs. Understanding the structure-function relationship of VGICs is crucial for our comprehension of their working mechanisms and role in diseases. In this Review, we discuss how advances in single-particle cryo-electron microscopy have afforded unprecedented structural insights into VGICs, especially on their interactions with clinical and investigational drugs. We present a comprehensive overview of the recent advances in the structural biology of VGICs, with a focus on how prototypical drugs and toxins modulate VGIC activities. We explore how these structures elucidate the molecular basis for drug actions, reveal novel pharmacological sites, and provide critical clues to future drug discovery.

10.
NAR Genom Bioinform ; 6(3): lqae097, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39131819

RESUMEN

Sorghum bicolor (L.) Moench is a significant grass crop globally, known for its genetic diversity. High quality genome sequences are needed to capture the diversity. We constructed high-quality, chromosome-level genome assemblies for two vital sorghum inbred lines, Tx2783 and RTx436. Through advanced single-molecule techniques, long-read sequencing and optical maps, we improved average sequence continuity 19-fold and 11-fold higher compared to existing Btx623 v3.0 reference genome and obtained 19 and 18 scaffolds (N50 of 25.6 and 14.4) for Tx2783 and RTx436, respectively. Our gene annotation efforts resulted in 29 612 protein-coding genes for the Tx2783 genome and 29 265 protein-coding genes for the RTx436 genome. Comparative analyses with 26 plant genomes which included 18 sorghum genomes and 8 outgroup species identified around 31 210 protein-coding gene families, with about 13 956 specific to sorghum. Using representative models from gene trees across the 18 sorghum genomes, a total of 72 579 pan-genes were identified, with 14% core, 60% softcore and 26% shell genes. We identified 99 genes in Tx2783 and 107 genes in RTx436 that showed functional enrichment specifically in binding and metabolic processes, as revealed by the GO enrichment Pearson Chi-Square test. We detected 36 potential large inversions in the comparison between the BTx623 Bionano map and the BTx623 v3.1 reference sequence. Strikingly, these inversions were notably absent when comparing Tx2783 or RTx436 with the BTx623 Bionano map. These inversion were mostly in the pericentromeric region which is known to have low complexity regions and harder to assemble and suggests the presence of potential artifacts in the public BTx623 reference assembly. Furthermore, in comparison to Tx2783, RTx436 exhibited 324 883 additional Single Nucleotide Polymorphisms (SNPs) and 16 506 more Insertions/Deletions (INDELs) when using BTx623 as the reference genome. We also characterized approximately 348 nucleotide-binding leucine-rich repeat (NLR) disease resistance genes in the two genomes. These high-quality genomes serve as valuable resources for discovering agronomic traits and structural variation studies.

11.
J Soc Cardiovasc Angiogr Interv ; 3(1): 101066, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39131970

RESUMEN

Background: Lack of standardization in posttranscatheter aortic valve replacement (TAVR) conduction disturbance (CD) identification and treatment may affect permanent pacemaker implantation (PPI) rates and clinical outcomes. The safety and efficacy of a standardized TAVR CD algorithm has not been analyzed. This study analyzes the Optimize PRO post-TAVR CD management algorithm with Evolut PRO/PRO+ valves. Methods: Optimize PRO is a prospective, postmarket study implementing 2 strategies to reduce pacemaker rates: TAVR with cusp overlap technique and a post-TAVR CD algorithm. The 2-hour postprocedural electrocardiogram (ECG) stratified patients to early discharge in the absence of new ECG changes or to CD algorithms for (1) ECG changes with preexisting right or left bundle branch block (LBBB), interventricular conduction delay or first-degree atrioventricular block, (2) new LBBB, or (3) high-degree atrioventricular block (HAVB). Results: The interim analysis of the CD cohort consisted of 125/400 TAVR recipients. In the CD cohort, the 30-day new PPI rate was higher (28.1% vs 1.5%; P <.001), and 60 (48%) patients were discharged with a 30-day continuous ECG monitor. At 30 days, 90% of patients discharged with a monitor did not require PPI. Clinical outcomes, including mortality, stroke, bleeding, and reintervention, were similar in patients with and without CDs. No patient experienced sudden cardiac death. Conclusions: Effective management of CDs using a standard algorithm following Evolut TAVR provides similar 30-day safety outcomes to patients without CDs who undergo routine next day discharge. The CD algorithm may provide an effective strategy to recognize arrhythmias early, improve PPI utilization, and facilitate safe monitoring of patients after discharge.

12.
Int J Biol Sci ; 20(10): 3986-4006, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113711

RESUMEN

Lymph node (LN) metastasis is the dominant cause of death in bladder cancer (BCa) patients, but the underlying mechanism remains largely unknown. In recent years, accumulating studies have confirmed that bidirectional mitochondria-nucleus communication is essential for sustaining multiple function of mitochondria. However, little has been studied regarding whether and how the translocation of mitochondrial proteins is involved in LN metastasis. In this study, we first identified that the SUMO E3 ligase MUL1 was significantly downregulated in LN-metastatic BCa tissues and correlated with a good prognosis. Mechanistically, MUL1 SUMOylated HSPA9 at the K612 residue, leading to HSPA9 export from mitochondria and interaction with SUZ12 and in the nucleus. Consequently, MUL1 induced the ubiquitination-mediated degradation of SUZ12 and EZH2 and induced downstream STAT3 pathway inhibition in a HSPA9-dependent manner. Importantly, mutation of HSPA9 SUMO-conjugation motifs limited the translocation of mitochondrial HSPA9 and blocked the HSPA9-SUZ12 and HSPA9-EZH2 interactions. With mutation of the HSPA9 K612 site, the suppressive role of MUL1 overexpression was lost in BCa cells. Further in vitro and in vivo assays revealed that MUL1 inhibits the metastasis and proliferation of BCa cells. Overall, our study reveals a novel function and molecular mechanism of SUMO E3 ligases in LN metastasis.


Asunto(s)
Proteínas HSP70 de Choque Térmico , Metástasis Linfática , Ubiquitina-Proteína Ligasas , Neoplasias de la Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/genética , Humanos , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Línea Celular Tumoral , Mitocondrias/metabolismo , Animales , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Masculino , Sumoilación , Femenino , Proteínas Mitocondriales
13.
Midwifery ; 138: 104143, 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39154597

RESUMEN

BACKGROUND: Women with overweight (OW) and those with obesity (OB) tend to gain excessive weight during pregnancy, often resulting in adverse outcomes. The long-term effects of mobile health (mHealth) interventions on maternal and infant outcomes remain unclear. AIMS: To examine the effects of an mHealth intervention on OW and OB from the course of their pregnancy to six months postpartum. METHODS: A randomized controlled trial was conducted in northern Taiwan. Ninety-two pregnant women with a body mass index (BMI)of ≥25 kg/m2 were recruited from prenatal clinics at <17 weeks of gestation. Prepregnancy weight was baseline maternal weight, with data collected subsequently at the last assessment before childbirth and six months postpartum. The intervention group (IG) received the mHealth intervention, while the control group (CG) received standard antenatal care. The trial was registered on ClinicalTrials.gov (identifier: NCT04553731) with the initial registration date of September 16, 2020. FINDINGS: The IG tended to have a lower mean body weight than the CG at the last assessment before childbirth (82.23 kg vs 84.35 kg) and at six months postpartum (72.55 Kg vs 72.58 Kg). IG's newborn birth weight was significantly lower than CG's (3074.8 vs. 3313.6 g; p = 0.009). Regression analysis revealed that OB in IG had a significant reduction in weight before childbirth (ß = -7.51, p = 0.005) compared to OB in CG. Compared to OW in CG, both OW in IG (ß = -243.59, p = 0.027) and OB in IG (ß = -324.59, p = 0.049) were associated with decreased newborn birth weight. CONCLUSIONS: mHealth helped women with obesity to successfully manage their GWG and body weight before childbirth and newborns' birth weight, despite this effect not persisting to reduce weight retention at six months postpartum.

14.
Aquat Toxicol ; 274: 107049, 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39159590

RESUMEN

In this study, the impact of ammonia nitrogen stress on juvenile four-finger threadfin in pond culture was examined. The 96-hour median lethal concentration (LC50-96h) and safe concentration of ammonia nitrogen were assessed in juveniles with a body weight of 7.4 ± 0.6 g using ecotoxicological methods. The study design included a stress group exposed to LC50-96h levels of ammonia nitrogen and a control group without ammonia nitrogen exposure. To examine the physiological, biochemical, and metabolic effects of ammonia nitrogen on gill tissue, gill tissue samples were collected after 12, 24, 48, and 96 h of stress, with a resumption of treatment after 48 h. Compared to the control group, ammonia nitrogen adversely affected juvenile four-finger threadfin, with LC50-96h and safe concentration values of 20.70 mg/L and 2.07 mg/L, respectively. Exposure to ammonia nitrogen resulted in substantial gill damage, including fusion of lamellae, epithelial cell loss, and proliferation of chlorine-secreting cells. This tissue damage persisted even after a 48-h recovery period. Ammonia nitrogen stress triggered an increase in antioxidant enzyme activity (superoxide dismutase, catalase, and glutathione peroxidase) and malondialdehyde levels in gills, indicating oxidative stress from 12 h onwards. Although enzyme activity decreased over time, oxidative stress persisted even after recovery, suggesting an ongoing need for antioxidant defense. Metabolomics analysis showed significant alterations in 423 metabolites under ammonia nitrogen stress. Key metabolites such as L-arginine, taurine, 20-hydroxyarachidonic acid, 11,12-dihydroxy-5Z, 8Z, and 14Z eicosotrienic acid followed an increasing trend; uridine, adenosine, L-glutathione, and thymidine 5'-triphosphate followed a decreasing trend. These changes reflect metabolic adaptations to stress. In enriched metabolic pathways, the main differential pathways are membrane transport, lipid metabolism, and amino acid metabolism. After 48 h, significant differences were observed in 396 metabolites compared to the control group. Notably, L-arginine, choline, and L-histidine increased, while linoleic acid, adenosine, and glutathione decreased. Amino acid and lipid metabolism pathways were key affected pathways. Under ammonia nitrogen stress, juvenile four-finger threadfin increased the synthesis of unsaturated and saturated fatty acids to cope with low temperatures and bolster immune function by consuming spermidine. This adaptation helps to clear peroxides generated during fatty acid synthesis, thereby protecting cells from oxidative damage. This study provides insights for pond aquaculture and breeding of ammonia nitrogen-tolerant fish strains.

15.
Sci Total Environ ; 950: 175174, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39094646

RESUMEN

Tree-ring widths contain valuable historical information related to both forest disturbances and climate variability and changes within forests. However, current methods are still unable to accurately distinguish between disturbances and climate signals in tree rings, especially in the case of climate anomalies. To address this issue, we developed a novel method, called Growth Trends Clustering (GTC) that uses the distribution characteristics of tree-ring widths within a stand to distinguish the effects of climate and other forest disturbances. GTC employed a Gaussian mixture model to fit the probability density distribution of annual ring-width index (RWI) in a stand. Discriminative criteria were established to cluster diverse sub-distributions from the Gaussian mixture model into categories of growth release, suppression, or normal trends. This approach allowed us to identify the occurrence, duration, and severity of forest disturbances based on percentage changes in the growth release or suppression categories of trees. And the effect of climate on tree growth was assessed according to the mean statistics of the growth normal categories. Using common forest disturbances such as defoliating insects and thinning as examples, we validated our method using tree-ring collections from six sites in British Columbia and Quebec, Canada. We found that the GTC method was superior to traditional time-series analysis methods (e.g., Radial Growth Averaging, Boundary Line, Absolute Increase, and Curve Intervention Detection) for detecting past forest disturbances and was able to significantly enhance climate signals. In summary, the GTC method presented in this study introduces a novel statistical approach for accurately distinguishing between forest disturbances and climate signals in tree rings. This is particularly important for understanding forest disturbance regimes under climate change and for developing future disturbance mitigation strategies.

16.
Nat Commun ; 15(1): 6169, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103349

RESUMEN

As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels.


Asunto(s)
Secuestro de Carbono , Carbono , Cambio Climático , Bosques , Estaciones del Año , Tracheophyta , Madera , Carbono/metabolismo , Madera/metabolismo , Madera/química , Tracheophyta/metabolismo , Biomasa , Ecosistema , Ciclo del Carbono , Árboles/metabolismo
17.
Cell ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39094568

RESUMEN

Innate immune responses to microbial pathogens are regulated by intracellular receptors known as nucleotide-binding leucine-rich repeat receptors (NLRs) in both the plant and animal kingdoms. Across plant innate immune systems, "helper" NLRs (hNLRs) work in coordination with "sensor" NLRs (sNLRs) to modulate disease resistance signaling pathways. Activation mechanisms of hNLRs based on structures are unknown. Our research reveals that the hNLR, known as NLR required for cell death 4 (NRC4), assembles into a hexameric resistosome upon activation by the sNLR Bs2 and the pathogenic effector AvrBs2. This conformational change triggers immune responses by facilitating the influx of calcium ions (Ca2+) into the cytosol. The activation mimic alleles of NRC2, NRC3, or NRC4 alone did not induce Ca2+ influx and cell death in animal cells, suggesting that unknown plant-specific factors regulate NRCs' activation in plants. These findings significantly advance our understanding of the regulatory mechanisms governing plant immune responses.

18.
JACC Asia ; 4(7): 547-556, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39101116

RESUMEN

Background: There is growing interest in the intersection of frailty and heart failure (HF); however, large-sample longitudinal studies in the general population are lacking. Objectives: The goal of this study was to examine the longitudinal relationship between frailty and incident HF, and whether age and genetic predisposition could modify this association. Methods: This prospective cohort study included 340,541 participants (45.7% male; mean age 55.9 ± 8.1 years) free of HF at baseline in the UK Biobank. Frailty was assessed by using the Fried frailty phenotype and included weight loss, exhaustion, low physical activity, slow gait speed, and low grip strength. The weighted polygenetic risk score was calculated. Cox models were used to estimate these associations and the interaction between the 2 factors. Results: During a median 14.1 years of follow-up, 7,590 patients with HF were documented. Compared with nonfrail participants, both prefrail and frail participants had a positive association with the risk of incident HF (prefrail HR: 1.40 [95% CI: 1.17-1.67]; frail HR: 2.07 [95% CI: 1.67-2.57]). Exhaustion (HR: 1.21; 95% CI: 1.03-1.43), slow gait speed (HR: 1.62; 95% CI: 1.39-1.90), and low grip strength (HR: 1.31; 95% CI: 1.14-1.51) were associated with a greater risk of incident HF. Furthermore, genetic susceptibility did not significantly modify the associations (P interaction = 0.094), and the association was significantly strengthened in younger participants (P interaction = 0.008). Conclusions: Frailty status was associated with a higher risk of incident HF independent of genetic risk. A younger population may be more susceptible to HF when exposed to frailty. Whether the modification of frailty status represents another avenue for preventing HF warrants further investigation.

19.
Artículo en Inglés | MEDLINE | ID: mdl-39115240

RESUMEN

BACKGROUND: The ION system is a shape-sensing robotic-assisted bronchoscopy (SS-RAB) platform developed to biopsy peripheral pulmonary nodules (PPNs). There is a lack of data describing the use of this system in the Chinese population. The study aimed to assess the feasibility and safety of using SS-RAB to diagnose PPNs across multiple centers within China. METHODS: This prospective, multicenter study used SS-RAB in consecutive patients with solid or sub-solid PPNs 8 to 30 mm in largest diameter. Primary endpoints were diagnostic yield and the rates of procedure- or device-related complications. Radial endobronchial ultrasound (rEBUS) was to confirm lesion localization, followed by sampling, using the Flexision biopsy needle, biopsy forceps, and cytology brush. Subjects with nonmalignant index biopsy results were followed up to 6 months. RESULTS: A total of 90 PPNs were biopsied from 90 subjects across 3 centers using SS-RAB. The median nodule size was 19.4 mm (IQR: 19.3, 24.6) in the largest dimension. In all (100%) cases, the catheter successfully reached the target nodule with tissue samples obtained. The diagnostic yield was 87.8% with a sensitivity for malignancy of 87.7% (71/81). In a univariate analysis, nodule lobar location, presence of bronchus sign, and rEBUS view were associated with a diagnostic sample, but only rEBUS view showed an association in a multivariate analysis. The overall pneumothorax rate was 1.1% without pneumothorax requiring intervention, and there was no periprocedural bleeding. CONCLUSION: As an emerging technology in the Chinese population, SS-RAB can safely biopsy PPNs with strong diagnostic performance.


Asunto(s)
Broncoscopía , Estudios de Factibilidad , Neoplasias Pulmonares , Humanos , Broncoscopía/métodos , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , China , Anciano , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagen , Nódulos Pulmonares Múltiples/patología , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/diagnóstico , Procedimientos Quirúrgicos Robotizados/métodos , Nódulo Pulmonar Solitario/patología , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/diagnóstico , Adulto
20.
Neuroscience ; 556: 25-30, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39094819

RESUMEN

Cancer and depression are closely interrelated, particularly in patients with advanced cancer, who often present with comorbid anxiety and depression for various reasons. Recently, there has been a growing interest in the study of depression in cancer patients, with the aim of assessing the possible triggers, predictors, adverse events, and possible treatment options for depression in several common cancers. The objective of this narrative review is to synthesize the extant literature on the relationship between the occurrence and progression of depression in several common patient categories. The authors conducted a comprehensive review of 75 articles published in PubMed over the past five years. This review was further evaluated in the present paper. Ultimately, it was determined that depression is a prevalent and detrimental phenomenon among cancer patients, particularly those with advanced disease. Consequently, there is a pressing need to prioritize research and interventions aimed at improving the quality of life and psychosocial well-being of cancer patients, including those with advanced disease. The relationship between cancer and depression has been evolving dynamically in recent times. The current research findings indicate a strong association between cancer and depression. However, the direction of causality remains unclear. Focusing on depression in cancer patients may, therefore, be beneficial for these patients.

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