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A self‐reinforcing positive feedback is regarded as a critical process for maintaining alternative stable states (ASS); however, identification of ASS and quantification of positive feedbacks remain elusive in natural ecosystems. Here, we used large‐scale field surveys to search for ASS and a positive feedback mechanism under a wide range of habitats on the Tibetan Plateau. Using multiple methods, we proved that three stable states exist that accompany alpine marsh degradation. Positive feedbacks between changing soil moisture and plant community composition forced the ecosystem into another stable state, and the alteration of water use efficiency (WUE) of the component species contributed to this shift. This study provides the first empirical evidence that positive feedback loops maintain ASS in the alpine marsh ecosystem on the Tibetan Plateau. Our research revealed the powerful driving role of plants in transitions between states, which may support the conservation and restoration of global alpine marsh ecosystems. [ABSTRACT FROM AUTHOR]

Seed rain and the soil seed bank represent the dispersal of seeds in space and time, respectively, and can be important sources of recruitment of new individuals during plant community regeneration. However, the temporal dynamics of seed rain and the mechanisms by which the seed rain and soil seed bank may play a role in plant community regeneration with increased grazing disturbance remain unclear. Seed rain, soil seed bank, aboveground vegetation, and rodent density were sampled along a grazing gradient in an alpine marsh on the eastern Tibetan Plateau. We described the temporal dynamics of seed dispersal using Bayesian generalized mixed models, and nonmetric multidimensional scaling and the structural equation model were used to examine the effects of grazing disturbance on the relative role of seed rain and soil seed bank on aboveground plant community regeneration. The temporal dynamics of seed rain changed from a unimodal to a bimodal pattern with increased grazing disturbance. Both species diversity and seed density of the seed rain and seed bank increased significantly with increased grazing disturbance. Increased grazing disturbance indirectly increased the similarity of composition between seed rain, seed bank, and aboveground plant community by directly increasing species diversity and abundance of aboveground plant community. However, increased grazing disturbance also indirectly decreased the similarity of seed rain, soil seed bank, and aboveground plant community by directly increasing rodent density. The similarity between seed rain and aboveground plant community was greater than that of the soil seed bank and aboveground plant community with increased grazing disturbance. Grazing disturbance spreads the risk of seed germination and seedling establishment by changing the temporal dynamics of seed dispersal. Plants (positive) and rodents (negative) mediated the role of seed rain and soil seed bank in plant community regeneration. The role of seed rain in plant community regeneration is higher than the seed bank in disturbed alpine marshes. Our findings increase our understanding of the regeneration process of the plant community, and they provide valuable information for the conservation and restoration of alpine marsh ecosystems. [ABSTRACT FROM AUTHOR]

Flowering and fruiting phenology of plants is sensitive to environmental cues, and changes in reproductive phenology of individual plant species under climate change have been widely reported. However, how species‐level phenological responses scale up to affect community‐level reproductive phenology patterns (synchrony and reproductive duration) are still unclear.An experiment on the effects of nitrogen (N) addition and precipitation changes on reproductive phenological traits of 52 species was conducted in an alpine meadow on the eastern Tibetan Plateau to determine the influence of the phenological response in different functional groups on community‐level reproductive phenology.N addition significantly delayed the onset date of reproductive phenology of sedges (early‐flowering species) and advanced the end date of reproduction of forbs (late‐flowering species). Meanwhile, N addition reduced the number of individuals involved in reproduction of sedges and forbs, but it increased that of grasses (late‐flowering species). Furthermore, N addition increased reproductive synchrony, delayed the onset and shortened the duration of reproductive phenology at the community level. However, precipitation changes and their interaction with N addition had no significant effect on reproductive phenology of the alpine plant community.Synthesis. These results suggested that differences in the direction and magnitude of response of different species to N enrichment lead to compression of reproductive duration at the community level, increasing the degree of overlap between reproductive events, which could change future species diversity, trophic interactions and productivity accumulation in alpine meadows on the Tibetan Plateau. Overall, knowledge of phenological responses from plant functional groups to the community level contributes to robust prediction and mechanistic understanding of community structure and function in response to future climate change. [ABSTRACT FROM AUTHOR]

The timing of phenological events is highly sensitive to climate change, and may influence ecosystem structure and function. Although changes in flowering phenology among species under climate change have been reported widely, how species‐specific shifts will affect phenological synchrony and community‐level phenology patterns remains unclear. We conducted a manipulative experiment of warming and precipitation addition and reduction to explore how climate change affected flowering phenology at the species and community levels in an alpine meadow on the eastern Tibetan Plateau. We found that warming advanced the first and last flowering times differently and with no consistent shifts in flowering duration among species, resulting in the entire flowering period of species emerging earlier in the growing season. Early‐flowering species were more sensitive to warming than mid‐ and late‐flowering species, thereby reducing flowering synchrony among species and extending the community‐level flowering season. However, precipitation and its interactions with warming had no significant effects on flowering phenology. Our results suggest that temperature regulates flowering phenology from the species to community levels in this alpine meadow community, yet how species shifted their flowering timing and duration in response to warming varied. This species‐level divergence may reshape flowering phenology in this alpine plant community. Decreasing flowering synchrony among species and the extension of community‐level flowering seasons under warming may alter future trophic interactions, with cascading consequences to community and ecosystem function. [ABSTRACT FROM AUTHOR]

Climate warming has induced pronounced shifts in the phenology of alpine plants worldwide, yet the impact of these changes on plant reproduction remains unclear, although phenology plays a vital role in reproduction. Based on a 7‐year field warming and altered precipitation experiment initiated in 2017, we measured three reproductive phenological events and seven reproductive traits of six dominant species, belonging to two flowering functional groups, to assess the effects of climate change on reproductive phenology and the reproductive consequence of changing the phenology in an alpine meadow on the eastern Tibetan Plateau from 2021 to 2023. Warming significantly advanced the start of flowering in early‐spring flowering (ESF) and mid‐summer flowering (MSF) plants, while the fruiting period of ESF plants remained stable. Furthermore, warming led to a decrease in the number of seeds and productivity of alpine plants, while seed size remained stable. Phenological changes regulate the reproductive success of alpine plants. Specifically, the start of flowering for ESF plants and the start of fruiting for MSF plants regulated the number of seeds and productivity of the two flowering functional groups, respectively. The increase in phenological niche overlap and intensification of interspecific competition, caused by different phenological responses of the flowering functional groups to warming, also are key factors contributing to the decline in seed production of alpine plants. Synthesis. These results demonstrate that the reproductive success of alpine plants would be decreased by earlier reproduction under climate warming, and alpine plants tend to maintain stable seed size in response to climate change. Our study emphasizes the important regulatory and indicative role of reproductive phenology in the sexual reproduction of alpine plants under future climate change. [ABSTRACT FROM AUTHOR]

Background: Currently, the exploration of amblyopia treatment methods is gradually shifting to the restoration of binocular visual perceptual function. Binocular fusion function, as an important component of binocular visual function, mainly reflects the patient's ability to integrate the signals received from both eyes. In this study, we investigated the relationship between binocular fusion function and improvement in visual acuity during amblyopia treatment., Methods: A retrospective analysis was conducted on a cohort of patients with amblyopia, aged 3-14 years old, who visited an outpatient clinic in Shenzhen Eye Hospital between May 2021 and January 2023. The investigation included 105 patients (210 eyes) with isometropic or anisometropic amblyopia. All participants underwent cycloplegic refraction examination and binocular fusion function measurement. All patients underwent standard amblyopia treatment, and those with the best-corrected visual acuity (BCVA) of 0.6 or higher in the amblyopic eye of both eyes received binocular fusion training using a computer platform., Results: A statistically significant negative correlation (-0.263, P=0.007) was observed between the absolute difference in binocular BCVA and binocular fusion function at the start of treatment (baseline). Linear regression analysis revealed that the improvement in BCVA in the amblyopic eye exhibited correlations with several factors, including the baseline binocular BCVA difference, baseline BCVA of the amblyopic eye, improvement in binocular fusion function, and the number of fusion training sessions (regression coefficients: -0.463, -0.771, 0.007, and 0.063, respectively; all P<0.05). Two patterns of binocular fusion function development during treatment were identified using group-based trajectory modeling (GBTM): the slow growth pattern and the rapid growth pattern. The results of a multivariate logistic regression model indicated a statistically significant link between fusion training and the development pattern of binocular fusion function [odds ratio (OR): 5.219, 95% confidence interval (CI): 2.045-13.323]., Conclusions: Enhancing binocular fusion function may result in an improvement of BCVA in the amblyopic eye of patients with amblyopia. The frequency of binocular fusion training is crucial for rapid improvement in binocular fusion function., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tp.amegroups.com/article/view/10.21037/tp-24-125/coif). The authors have no conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)

Changes in reproductive phenology induced by warming are happening across the globe, with significant implications for plant sexual reproduction. However, the changes in plant reproductive output (number of flowers and fruits) and success (successful fruits/total flowers) in response to climate change have not been well characterized. Here, we conducted a warming and altered precipitation experiment in an alpine meadow on the eastern Tibetan Plateau to investigate the effects of climate change on the reproductive phenology and success of six common species belonging to two flowering functional groups. We found that warming advanced the start of flowering and the start of fruiting in mid-summerflowering plants. Warming reduced the reproductive output of early-spring flowering plants but did not change their reproductive success. The effects of warming and altered precipitation on the reproductive output and success of mid-summer flowering plants were year-dependent, and the fruiting phenology regulated the response of the mid-summer flowering plant's reproductive success to climate change. These findings highlight the critical role of fruiting phenology in the reproductive success of alpine plants and imply that alpine plants may reduce their fitness by producing fewer flowers and fruits under climate warming, especially for later flowering plants.

Objective: To explore the clinical features and genetic basis of a patient with glycogen storage disease type VI (GSD-VI)., Methods: Clinical data of the patient was collected. Genomic DNA was extracted from peripheral blood samples of the proband and his parents. Genetic variants were detected by using whole exome sequencing. Candidate variants were verified by Sanger sequencing followed by bioinformatics analysis., Results: The proband presented fasting hypoglycemia, hepatomegaly, growth retardation, transaminitis, metabolic acidosis and hyperlactatemia. Liver biopsy indicated GSD. Novel compound heterozygous PYGL gene variants (c.2089A>G/c.158&#95;160delACT) were detected in the proband. Compound heterozygosity was confirmed by Sanger sequencing of the patient's genomic DNA. Provean and MutationTaster predicted the two variants as deleterious and the variant sites are highly conserved., Conclusion: The compound heterozygous variants (c.2089A>G/c.158&#95;160delACT) of PYGL gene probably underlay the GSD in the patient. The two novel variants have expanded the spectrum of PYGL gene variants and provided the basis for genetic counseling of the family.

Curcumin is known to possess anti‑inflammatory properties. Despite the fact that curcumin is known to be a strong inhibitor of H+, K+‑ATPase activity, the mechanism underlying the curcumin‑induced inhibition of the transcription of the H+, K+‑ATPase α subunit in gastric mucosal parietal cells remains unclear. The present study investigated the possible mechanism by which curcumin inhibits stomach H+, K+‑ATPase activity during the acute phase of gastric ulcer disease. A rat model of stress‑induced gastric ulcers was produced, in which the anti‑ulcer effects of curcumin were examined. Curcumin‑induced inhibition of the H+, K+‑ATPase promoter via histone acetylation, was verified using a chromatin immunoprecipitation assay. The results showed that curcumin improved stress‑induced gastric ulcer disease in rats, as demonstrated by increased pH values and reduced gastric mucosal hemorrhage and ulcer index. These effects were accompanied by a significant reduction in the level of histone H3 acetylation at the site of the H+, K+‑ATPase promoter and in the expression of the gastric H+,K+‑ATPase α subunit gene and protein. In conclusion, curcumin downregulated the acetylation of histone H3 at the site of the H+, K+‑ATPase promoter gene, thereby inhibiting the transcription and expression of the H+, K+‑ATPase gene. Curcumin was shown to have a preventive and therapeutic effect in gastric ulcer disease.