Cyclic Changes Research Articles

Climate-driven succession in marine microbiome biodiversity and biogeochemical function.

Seasonal and El Niño-Southern Oscillation (ENSO) warming result in similar ocean changes as predicted with climate change. Climate-driven environmental cycles have strong impacts on microbiome diversity, but impacts on microbiome function are poorly understood. We quantified changes in microbial genomic diversity and functioning over 11 years covering seasonal and ENSO cycles at a coastal site in the southern California Current. We observed seasonal oscillations between large genome lineages during cold, nutrient rich conditions in winter and spring versus small genome lineages, including Prochlorococcus and Pelagibacter , in summer and fall. Parallel interannual changes separated communities depending on ENSO condition. Biodiversity shifts translated into clear oscillations in microbiome functional potential. Ocean warming induced an ecosystem with less iron but more macronutrient stress genes, depressed organic carbon degradation potential and biomass, and elevated carbon-to-nutrient biomass ratios. The consistent microbial response observed across time-scales points towards large climate-driven changes in marine ecosystems and biogeochemical cycles.

Dry hydroclimates in the late Palaeocene-early Eocene hothouse world

Extreme global warming can produce hydroclimate changes that remain poorly understood for sub-tropical latitudes. Late Palaeocene-early Eocene (LPEE; ~58-52 Ma) proto-Mediterranean zones of the western Tethys offer opportunities to assess hydroclimate responses to massive carbon cycle perturbations. Here, we reconstruct LPEE hydroclimate conditions of these regions and find that carbon cycle perturbations exerted controls on orbitally forced hydroclimate variability. Long-term (~6 Myr) carbon cycle changes induced a gradual precipitation/moisture reduction, which was exacerbated by some short-lived (<200 kyr) carbon cycle perturbations that caused rapid warming and exceptionally dry conditions in western Tethyan continental areas. Hydroclimate recovery following the greatest short-lived global warming events took ~24-27 kyr. These observations support the notion that anthropogenically driven warming can cause widespread aridification with impacts that may last tens of thousands of years.

Exploring Mutation-Driven Changes in the ATP-ADP Conformational Cycle of Human Hsp70 by All-Atom MD Adaptive Sampling.

Hsp70 belongs to a family of molecular chaperones ubiquitous through organisms that assist client protein folding and prevent aggregation. It works through a tightly ATP-regulated allosteric cycle mechanism, which organizes its two NBD and SBD into alternate open and closed arrangements that facilitate loading and unloading of client proteins. The two cytosolic human isoforms Hsc70 and HspA1 are relevant targets for neurodegenerative diseases and cancer. Illuminating the molecular details of Hsp70 functional dynamics is essential to rationalize differences among the well-characterized bacterial homologue DnaK and the less explored human forms and develop subtype- or species-selective allosteric drugs. We present here a molecular dynamics-based analysis of the conformational dynamics of HspA1. By using an "allosterically impaired" mutant for comparison, we can reconstruct the impact of the ADP-ATP swap on interdomain contacts and dynamic coordination in full-length HspA1, supporting previous predictions that were, however, limited to the NBD. We model the initial onset of the conformational cycle by proposing a sequence of structural steps, which reveal the role of a specific human sequence insertion at the linker, and a modulation of the angle formed by the two NBD lobes during the progression of docking. Our findings pinpoint functionally relevant conformations and set the basis for a selective structure-based drug discovery approach targeting allosteric sites in human Hsp70.

Punctuated aggradation and flow criticality in deep water channel systems

AbstractSubmarine channels are conduits for the transfer of material to deep water by sediment gravity flows. Some channels clearly show meandering patterns in planform that have attracted comparisons with fluvial systems. Many submarine channels, however, are aggradational. Transitions from meandering (at grade) channels to aggradational channels have been described in the subsurface, from seismic data. A field example is presented here in which these meandering and aggradational states may alternate several times during the overall development of a fourth‐order sequence before the system is temporarily or permanently abandoned. This implies a change in flow state from one where successive flows behave similarly over extended periods, to one in which the flow parameters are progressively changing. The cause of these cyclic changes is unclear. The generation of sedimentary architectures so strikingly comparable to those of meandering fluvial systems provides strong evidence in favour of stably stratified, essentially two‐layer flows, in which the lower high‐density part is channel‐confined, with a normal (i.e. fluvial‐like) secondary circulation, and the upper, low‐density part extends onto the overbank regions adjacent to the channel, with minimal mixing and entrainment. Such flows are described as subcritical, in line with published experimental and numerical work, allowing that the critical Froude number in such settings may not be unity. The switch to an aggradational state may be linked to changes in flow criticality, but the ultimate driver for these alternations in flow properties remains unknown.

Visualization of Tetrahedral Li in the Alkali Layers of Li-Rich Layered Metal Oxides.

Understanding Li+ ion diffusion pathways in Li-rich layered transition metal (TM) oxides is crucial for understanding the sluggish kinetics in anionic O2- redox. Although Li diffusion within the alkali layers undergoes a low-barrier octahedral-tetrahedral-octahedral pathway, it is less clear how Li diffuses in and out of the TM layers, particularly given the complex structural rearrangements that take place during the oxidation of O2-. Here, we develop simultaneous electron ptychography and annular dark field imaging methods to unlock the Li migration pathways in Li1.2Ni0.13Mn0.54Co0.13O2 associated with structural changes in the charge-discharge cycle. At the end of TM oxidation and before the high-voltage O oxidation plateau, we show that the Li migrating out of the TM layers occupies the alkali-layer tetrahedral sites on opposite sides of the TM layers, forming Li-Li dumbbell configurations, consistent with the density functional theory calculations. Also occurring are the TM migration and phase transition from O3 to O1 stacking, leading to unstable tetrahedral Li and the absence of Li contrast in imaging. Upon further Li deintercalation to 4.8 V, most of the tetrahedral Li are removed. After discharging to 2 V, we did not identify the reformation of tetrahedral Li but observed permanently migrated TMs at the alkali-layer sites, disfavoring the Li occupying the tetrahedral sites for diffusion. Our findings suggest a landscape of Li diffusion pathways in Li-rich layered oxides and strategies for minimizing the disruption of Li diffusion.

Study on temperature regulation capability of asphalt mixture modified by dual phase change material used in ultra-thin overlay

ABSTRACT A dual-phase change material (DPCM) containing polyethylene glycol (PEG) 400/expanded graphite (EG) and PEG1500/EG with both high and low-temperature regulation capacities was prepared. It was added as an additive to the NovaChip-Type C asphalt mixtures. Laboratory and field temperature regulation tests were designed. The images taken by SEM showed that PEG was fully adsorbed by EG and the structure of DPCM was stable. The test results showed the DPCM has good durability in the cyclic phase change process. The modified asphalt binders with different DPCM content showed different heat storage capacity. The results of temperature regulation tests showed that the addition of DPCM effectively reduced the temperature change rate of asphalt mixtures. With 1.88% DPCM, the extremum of high temperature of asphalt mixtures reduced by 2.3°C while the extremum of low temperature increased by 2.0°C. In terms of road performance, the cracking resistance at low temperature of asphalt mixtures gradually improved with the increase of DPCM content. Meanwhile, the rutting resistance at high temperature and water damage resistance still met the requirements of the specification. The DPCM had a good effect on restraining the occurrence of road diseases caused by temperature and prolonging the service life of the road.

Risk assessment of 2β,3β-19α-trihydroxyursolic acid from Rubus imperialis (Rosaceae) in HepG2/C3A cells via genotoxicity, metabolism, and cell growth.

Rubus imperialis (Rosaceae) is a Brazilian medicinal plant that already exhibited therapeutical perspectives. However, previous studies revealed cellular and/or genetic toxicity of extracts from aerial parts of this plant, as well as other species of the Rubus genus. Being 2β,3β-19α-trihydroxyursolic acid (2B) one of the major compounds of this plant, with proven pharmacological effect, it is important to investigate the biosafety of this isolated compound. Therefore, in the present study, (2B) was tested by several cytogenotoxic endpoints up to 20 μg/ml in human hepatoma HepG2/C3A cells. The test compound did not produce any decreased cell viability, DNA damage, chromosomal mutations, cell cycle changes, or apoptotic effects in the tested cells. Additionally, RT-qPCR analysis revealed the downregulation of CYP3A4 (metabolism), M-TOR (cell death), and CDKN1A (cell cycle) genes. Under the experimental conditions used, the 2B compound did not show cytogenotoxic activity after a single exposure to HepG2/C3A human cells.

Genesis and reservoir preservation mechanism of 10 000‐m ultradeep dolomite in Chinese craton basin

AbstractThe 10 000‐m ultradeep dolomite reservoir holds significant potential as a successor field for future oil and gas exploration in China's marine craton basin. However, major challenges such as the genesis of dolomite, the formation time of high‐quality reservoirs, and the preservation mechanism of reservoirs have always limited exploration decision‐making. This research systematically elaborates on the genesis and reservoir‐forming mechanisms of Sinian–Cambrian dolomite, discussing the ancient marine environment where microorganisms and dolomite develop, which controls the formation of large‐scale Precambrian–Cambrian dolomite. The periodic changes in Mg isotopes and sedimentary cycles show that the thick‐layered dolomite is the result of different dolomitization processes superimposed on a spatiotemporal scale. Lattice defects and dolomite embryos can promote dolomitization. By simulating the dissolution of typical calcite and dolomite crystal faces in different solution systems and calculating their molecular weights, the essence of heterogeneous dissolution and pore formation on typical calcite and dolomite crystal faces was revealed, and the mechanism of dolomitization was also demonstrated. The properties of calcite and dolomite (104)/(110) grain boundaries and their dissolution mechanism in carbonate solution were revealed, showing the limiting factors of the dolomitization process and the preservation mechanism of deep buried dolomite reservoirs. The in situ laser U‐Pb isotope dating technique has demonstrated the timing of dolomitization and pore formation in ancient carbonate rocks. This research also proposed that dolomitization occurred during the quasi‐contemporaneous or shallow‐burial periods within 50 Ma after deposition and pores formed during the quasi‐contemporaneous to the early diagenetic periods. And it was clear that the quasi‐contemporaneous dolomitization was the key period for reservoir formation. The systematic characterization of the spatial distribution of the deepest dolomite reservoirs in multiple sets of the Sinian and the Cambrian in the Chinese craton basins provides an important basis for the distribution prediction of large‐scale dolomite reservoirs. It clarifies the targets for oil and gas exploration at depths over 10 000 m. The research on dolomite in this study will greatly promote China's ultradeep oil and gas exploration and lead the Chinese petroleum industry into a new era of 10 000‐m deep oil exploration.

Mechano-Electro-Chemical Impedance Spectroscopy (MeIS): Concept, Theory and Experiment

Electrochemical impedance spectroscopy (EIS) is a widely used non-invasive method for characterizing and diagnosing lithium-ion batteries (LIBs)1. The key to utilizing EIS lies in interpreting the measured impedance spectrum. This involves fitting the experimental data to an impedance model to understand the internal states of the battery. However, due to the multiscale and multiphysical nature of LIBs, impedance models can be complex and have many parameters. As a result, there is a high risk of over-fitting the experimental data, making the interpretation of the EIS data challenging2. In addition to electrical signals, the mechanical responses of a LIB, such as pressure and thickness change during charge/discharge, provides valuable information for characterization and diagnosis3-5. Most existing analyses of mechanical signals focus on the time domain. Recently, von Kessel et al6 introduced Mechanical Impedance Spectroscopy (MIS) as a frequency-analyzing tool for characterizing LIBs. The MIS spectrum (the displacement response subject to a cyclic pressure trigger) turned out to vary with the state of the batteries, demonstrating the great potential of using mechanical responses in the frequency domain to characterize and diagnosis the LIBs. Nevertheless, measuring displacement for LIBs in real-world applications is challenging, as it requires a customized testing machine to measure the micrometer-level displacement while exerting a sinusoidal pressure input. This requirement for customized testing equipment limits the application scope of the MIS method.A free LIB cell cyclic changes its dimensions during charge/discharge. Under confinements where dimension change constricted, cyclic pressure change will be generated, which could be used for frequency analysis. This observation led us to propose a new method called mechano-electro-chemical impedance spectroscopy (MeIS). An MeIS spectrum is defined as the ratio of pressure perturbation to the input current, denoted as . Measurements can be obtained by perturbating the battery with sinusoidal current and recording the resulting pressure or displacement response. The basic transfer function for MeIS is derived from the electro-chemo-mechanical coupling of the porous electrode. The MeIS consists of two parts, the MIS term and an electrochemical term resulting from the insertion/extraction deformation of the electroactive particles. The great advantage of MeIS is that it requires only a pressure or displacement sensor and a charger capable of providing sinusoidal current, making it potentially applicable in in-field scenarios such as management of EV batteries or real-time monitoring of a battery-based energy storage facility. Sensitivity analysis reveals that MeIS is highly sensitive to changes in the structure of porous electrodes, thus providing valuable insights into the internal structural integrity and degradation of LIBs. In addition, the experimental design and demonstrational results are also provided. We believe that MeIS could serve as a convenient and useful complement to EIS, enhancing the non-invasive diagnostic toolbox for LIBs.Reference: K. Mc Carthy, H. Gullapalli, K. M. Ryan, and T. Kennedy, Journal of The Electrochemical Society, 168 (8), (2021).F. Ciucci, Current Opinion in Electrochemistry, 13 132-139 (2019).J. Zhu, T. Wierzbicki, and W. Li, Journal of Power Sources, 378 153-168 (2018).B. Rieger, S. Schlueter, S. V. Erhard, J. Schmalz, G. Reinhart, and A. Jossen, Journal of Energy Storage, 6 213-221 (2016).Z. J. Schiffer, J. Cannarella, and C. B. Arnold, Journal of The Electrochemical Society, 163 (3), A427-A433 (2015).O. von Kessel, T. Deich, S. Hahn, F. Brauchle, D. Vrankovic, T. Soczka-Guth, and K. P. Birke, Journal of Power Sources, 508 (2021). Figure 1

Catalytic Activities of Ir-Based Pyrochlore-Type Oxides Doped with Divalent Cations for Oxygen Evolution Reaction

Alternative energy sources to fossil fuels are essential for a sustainable society, and hydrogen energy is expected to be a solution to environmental and energy problems. Currently, proton exchange membrane water electrolyzers are becoming widely used for the electrochemical production of hydrogen due to their advantages such as high efficiency. However, the highly acidic conditions and the large overpotentials of oxygen evolution reaction (OER) at the anode are problems, and the development of catalysts that are stable and highly active in acidic aqueous solutions is important for further popularization.Ir-based oxides with pyrochlore structure (A2B2O7) are known to exhibit high catalytic activities in acidic aqueous solutions. Recently, it has been reported that the improved catalytic activities of Pr2Ir2O7 by Zn doping, which controlled the composition of A-site elements in the pyrochlore structure [1]. In this study, we synthesized Pr2-x MgxIr2O7 (x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5), in which a part of trivalent cation Pr3+ was replaced by divalent cation Mg2+ and improved the OER catalytic activity in acidic aqueous solutions.Pr2-x MgxIr2O7 was synthesized by the hydrothermal method. The catalyst was mixed with a conductivity aid carbon (Vulcan XC-72) and a cationic conductive ionomer (Nafion) at a weight ratio of 5:1:1 and dispersed in 2-propanol to form a catalyst ink. The catalytic activity was evaluated by cyclic voltammetry (CV) using a glassy carbon rotating disk electrode (RDE) as a working electrode, a reversible hydrogen electrode (RHE) as a reference electrode, and a platinum wire as a counter electrode. The electrolyte was a 0.1 mol dm-3 HClO4 solution saturated with oxygen, and the CV scanning range was 1.1 to 1.7 V with respect to the RHE, scanning speed was 20 mV s-1, and the RDE rotation speed was 1200 rpm. The stability of the catalyst in acidic aqueous solutions was evaluated by chronopotentiometry (CP) using the same cell.X-ray diffraction and energy-dispersive X-ray analysis measurements of the synthesized materials confirmed that the desired compounds were obtained, and CV measurements showed that the OER activity of Pr2-x MgxIr2O7 increased in the first 20 cycles for all compositions, and then stabilized over several tens of cycles. The cycle change was similar to that of Pr2Ir2O7, suggesting that the surface rearrangement proceeds in acidic aqueous solutions [2]. Linear sweep voltammogram (LSV) and OER activity normalized by Brunauer-Emmett-Teller (BET) specific surface area were measured at the 20th cycle, and the catalytic activity stabilized at a high value. The OER activity was enhanced by Mg substitution in the catalysts of Pr2-x Mg x Ir2O7.References L. Zhu, C. Ma, Z. Wang, X. Gong, L. Cao, and J. Yang, Appl. Surf. Sci., 31, 151840 (2022).C. Shang, C. Cao, D. Yu, Y. Yan, Y. Lin, H. Li, T. Zheng, X. Yan, W. Yu, S. Zhou, and J. Zeng, Adv. Mater., 31, 1805104 (2018).

Design of Lithium Metal Anode and Other High-Capacity Alloy Anodes Solid-State Batteries in Context of Contact Loss between Anode and Solid Electrolyte Separator

Cyclic volume changes and non-uniform electrodeposition/stripping, among other cycling-induced chemo-mechanical degradation of lithium metal and lithium-alloy solid state batteries, lead to contact loss between the anode and the solid electrolyte separator[1, 2]. In-operando experiments have shown ac-celerated short-circuiting behavior due to contact loss in “anode-free” solid-state batteries[2]. Simulations reveal the relationship between active area fraction and the ratio of effective conductivities in made-up active area configurations[3]. Through modeling experiments using imputed active con-tact area of lithium-metal anode batteries, we quantify the effects of this contact loss in terms of accelerated chemo-mechanical degradation and de-creased rate capability. Specifically, we (1) quantify the interfacial resistance due to this contact loss, (2) show non-uniform local current density distribution such that local current densities could exceed lithium filament growth critical current densities, (3) show uniaxial stress inhomogeneity due to non-uniform reaction at the anode/separator interface, and (4) show non-uniform reaction distribution at the positive electrode.Besides allowing for the optimization of designs to minimize contact loss, our work sheds light on tradeoffs in the design of solid electrolyte separators.

Associations of luteal phase changes in vagally mediated heart rate variability with premenstrual emotional changes

BackgroundA recent meta-analysis revealed that vagally mediated heart rate variability (vmHRV; a biomarker of emotion regulation capacity) significantly decreases in the luteal phase of the menstrual cycle. As two follow-up studies suggest, these vmHRV decreases are driven primarily by increased luteal progesterone (P4). However, analyses also revealed significant interindividual differences in vmHRV reactivity to the cycle, which is in line with longstanding evidence for interindividual differences in mood sensitivity to the cycle. The present study begins to investigate whether these interindividual differences in vmHRV cyclicity can explain who is at higher risk of showing premenstrual emotional changes. We expected a greater degree of midluteal vmHRV decrease to be predictive of a greater premenstrual increase in negative affect.MethodsWe conducted an observational study with a naturally cycling community sample (N = 31, M = 26.03 years). Over a span of six weeks, participants completed (a) daily ratings of negative affect and (b) counterbalanced lab visits in their ovulatory, midluteal, and perimenstrual phases. Lab visits were scheduled based on positive ovulation tests and included assessments of baseline vmHRV and salivary ovarian steroid levels.ResultsIn line with previous research, multilevel models suggest that most of the sample shows ovulatory-to-midluteal vmHRV decreases which, however, were not associated with premenstrual emotional changes. Interestingly, it was only the subgroup with luteal increases in vmHRV whose negative affect markedly worsened premenstrually and improved postmenstrually.ConclusionThe present study begins to investigate cyclical changes in vmHRV as a potential biomarker of mood sensitivity to the menstrual cycle. The results demonstrate a higher level of complexity in these associations than initially expected, given that only atypical midluteal increases in vmHRV are associated with greater premenstrual negative affect. Potential underlying mechanisms are discussed, among those the possibility that luteal vmHRV increases index compensatory efforts to regulate emotion in those with greater premenstrual negative affect. However, future studies with larger and clinical samples and more granular vmHRV assessments should build on these findings and further explore associations between vmHRV cyclicity and menstrually related mood changes.

Unveiling the role of protein kinase A (PKA) activity in bovine oviductal epithelial cells: implications on apoptotic signaling pathways during the estrous cycle.

The complex interactome crucial for successful pregnancy is constituted by the intricate network of endocrine and paracrine signaling pathways, involving gametes, embryos, and the female reproductive tract. Specifically, the oviduct exhibits distinct responses to gametes and early embryos during particular phases of the estrus cycle, a process tightly regulated by reproductive hormones. Moreover, these hormones play a pivotal role in orchestrating cyclical changes within oviductal epithelial cells. To unravel the molecular mechanisms underlying these dynamic changes, our study aimed to investigate the involvement of protein kinase A (PKA) in oviductal epithelial cells throughout the estrus cycle and in advanced pregnancy, extending our studies to oviductal epithelial cell in primary culture. By a combination of 2D-gel electrophoresis, Western blotting, and mass spectrometry, we identified 17 proteins exhibiting differential phosphorylation status mediated by PKA. Among these proteins, we successfully validated the phosphorylation status of heat shock 70kDa protein (HSP70), aconitase 2 (ACO2), and lamin B1 (LMNB1). Our findings unequivocally demonstrate the dynamic regulation of PKA throughout the estrus cycle in oviductal epithelial cells. Also, analysis by bioinformatics tools suggest its pivotal role in mediating cyclical changes possibly through modulation of apoptotic pathways. This research sheds light on the intricate molecular mechanisms underlying reproductive processes, with implications for understanding fertility and reproductive health.

Biological analysis method based on the relationship between athlete’s PSI rhythm and sports injury

Biorhythm is the law of cyclical changes in individual life activity characteristics as time changes. Biorhythm is an internal law of a biological organism, which comes from the changes that a biological organism is affected by changes in the external environment during natural activities, so its change law is similar to the cycle of the natural environment. Biological rhythms play an important role in mediating human body functions, vital activities, body temperature and other physiological reactions. The balance and stability of biological rhythms can ensure the healthy life activities of the human body. Disrupting the balance of biological rhythms may cause various kinds of human body. In this paper, the research of biological analysis method based on the relationship between athlete’s PSI (Physical, Sensitive, Intellectual) rhythm and sports injury is mainly introduced, and ideas and directions are intended to be provided for analyzing the relationship between athlete’s physical strength, emotion, intelligence and sports injury. This paper proposes a research strategy based on the biological analysis method of athlete’s PSI rhythm and sports injury, including measurement of biological rhythm, literature retrieval method, expert interview method, questionnaire survey method, clustering algorithm-based biological analysis method. A research experiment on the biological analysis method of the relationship between PSI rhythm and sports injury is conducted. The experimental results of this paper indicated that most sports injuries of athletes occur in the critical period of PSI rhythm, with an average incidence of 70.14%. Athletes’ training and competition can be avoided in this critical period as much as possible.

Menstrual Cycle Variations in Wearable-Detected Finger Temperature and Heart Rate, But Not in Sleep Metrics, in Young and Midlife Individuals.

Most studies about the menstrual cycle are laboratory-based, in small samples, with infrequent sampling, and limited to young individuals. Here, we use wearable and diary-based data to investigate menstrual phase and age effects on finger temperature, sleep, heart rate (HR), physical activity, physical symptoms, and mood. A total of 116 healthy females, without menstrual disorders, were enrolled: 67 young (18-35 years, reproductive stage) and 53 midlife (42-55 years, late reproductive to menopause transition). Over one menstrual cycle, participants wore Oura ring Gen2 to detect finger temperature, HR, heart rate variability (root mean square of successive differences between normal heartbeats [RMSSD]), steps, and sleep. They used luteinizing hormone (LH) kits and daily rated sleep, mood, and physical symptoms. A cosinor rhythm analysis was applied to detect menstrual oscillations in temperature. The effect of menstrual cycle phase and group on all other variables was assessed using hierarchical linear models. Finger temperature followed an oscillatory trend indicative of ovulatory cycles in 96 participants. In the midlife group, the temperature rhythm's mesor was higher, but period, amplitude, and number of days between menses and acrophase were similar in both groups. In those with oscillatory temperatures, HR was lowest during menses in both groups. In the young group only, RMSSD was lower in the late-luteal phase than during menses. Overall, RMSSD was lower, and number of daily steps was higher, in the midlife group. No significant menstrual cycle changes were detected in wearable-derived or self-reported measures of sleep efficiency, duration, wake-after-sleep onset, sleep onset latency, or sleep quality. Mood positivity was higher around ovulation, and physical symptoms manifested during menses. Temperature and HR changed across the menstrual cycle; however, sleep measures remained stable in these healthy young and midlife individuals. Further work should investigate over longer periods whether individual- or cluster-specific sleep changes exist, and if a buffering mechanism protects sleep from physiological changes across the menstrual cycle.

Effects of E-Cigarettes on the Lung and Systemic Metabolome in People with HIV.

The popularity of e-cigarettes (vaping) has soared, creating a public health crisis among teens and young adults. Chronic vaping can induce gut inflammation and reduce intestinal barrier function through the production of the proinflammatory molecule hydrogen sulfide (H2S). This is particularly concerning for people with HIV (PWH) as they already face impaired immune function and are at a higher risk for metabolic dysregulation, diabetes, and chronic liver disease. Furthermore, PWH experience unhealthy behaviors, making it crucial to understand the systemic metabolic dysregulation and pathophysiological mechanisms associated with vaping in this population. Here, we employed liquid chromatography-mass spectrometry (LC-MS)-based metabolomics to investigate the upper respiratory, circulation, and gut metabolic profiles of PWH who vape (n = 7) and smoke combustible tobacco/marijuana (n = 6) compared to control participants who did not vape or smoke (n = 10). This hypothesis-generating exploratory study revealed systemic alterations in purine, neurotransmitter, and vitamin B metabolisms and tissue-specific changes in inflammatory pathways and cryptic sulfur cycling associated with vaping and combustible tobacco/marijuana smoking in PWH. In addition, this study provides the first link between microbial-derived metabolite 2,3-dihydroxypropane-1-sulfonate (DHPS) and vaping/smoking (tobacco and marijuana)-induced metabolic dyshomeostasis in the gut. These findings highlight the importance of identifying the full biological and clinical significance of the physiological changes and risks associated with vaping.

Menstrual Changes in Women Who Undergo Sleeve Gastrectomy in Saudi Arabia.

Introduction Obesity affects over 650 million globally, with rising rates posing significant public health challenges, especially among Saudi Arabian women. Obesity correlates with menstrual irregularities and reproductive health issues such as polycystic ovary syndrome (PCOS). Bariatric surgery (BS), particularly laparoscopic sleeve gastrectomy (LSG), is increasingly used due to its safety and effectiveness in treating obesity-related conditions. This study explores LSG's impact on menstrual cycles and fertility in Saudi women, aiming to optimize patient care and understand surgical effects on hormonal dynamics and reproductive health. Methodology It is a cross-sectional design among Saudi women post-sleeve gastrectomy from December 2023 to May 2024. Variables included age, marital status, and region, with primary outcomes focusing on menstrual cycle changes post surgery. Results Our study includes 387 participants, and demographic characteristics showed a significant proportion aged 26-35 years (n=147, 38.0%) and 36-45 years (n=119, 30.7%), with the majority being married (n=230, 59.4%). Regional distribution highlighted the south as the most represented (n=139, 35.9%), followed by the central (n=74, 19.1%). About 30.2% (n=117) reported chronic conditions. Post surgery, 70.5% (n=273) experienced menstrual changes, with regular cycles being the most common (n=102, 26.3%). Logistic regression indicated younger age as a protective factor against menstrual changes (p=0.028), while pre-surgery menstrual irregularities significantly predicted post-surgery changes (p=0.002). Regional analysis showed no significant association between geographic location and post-surgery menstrual changes (p=0.140). Overall, quality of life post-surgery was rated highly by participants, with 70.8% (n=274) giving ratings of 4 or 5. Conclusion Our study highlights a high prevalence of post-sleeve gastrectomy menstrual changes, predominantly regular cycles. Younger age appears protective, while pre-existing menstrual irregularities strongly predict postoperative changes. Regional differences did not significantly influence outcomes. Overall, participants reported high satisfaction with their quality of life post surgery.

Synthesis and cytotoxic activity of madecassic acid-silybin conjugate compounds in liver cancer cells.

A series of 14 conjugates of 2α,3β,23-triacetyl-madecassic acid and silybin were designed and synthesized. The madecassic acid unit was linked to silybin either directly at position C-7 or C-3; or through an amino acid linker (glycine, β-alanine, or 11-aminoundecanoic acid) at position C-3. The conjugates were tested in vitro for their cytotoxic effect on HepG2 cells using the MTT assay. The results confirmed that the conjugated compounds demonstrated a stronger cytotoxic effect compared to the parent compounds. Of these compounds, the most promising conjugate, compound 8, was evaluated for cytotoxic activity in the additional Hep3B, Huh7, and Huh7R human hepatocellular carcinoma cell lines and also for cell cycle changes and induction of apoptosis in HepG2 cells. This compound caused a rapid and significant induction of caspase 3 activity and induced cell cycle arrest in the S phase - effects distinct from the activity of madecassic acid. This is the first study on the synthesis and cytotoxicity of madecassic acid-silybin conjugates, and of their testing against liver cancer cell lines and provides evidence for a distinct biological profile versus madecassic acid alone.

Effect of Selinexor on Proliferation and Apoptosis of Acute Myeloid Leukemia Kasumi-1 Cells

To investigate the effects of selinexor, a inhibitor of nuclear export protein 1 (XPO1) on the proliferation inhibition and apoptosis of Kasumi-1 cells in acute myeloid leukemia (AML). MTS method was used to detect the inhibitory effect of different concentrations of selinexor on the proliferation of Kasumi-1 cells at different time points. The apoptosis rate and cell cycle changes after treatment with different concentration of selinexor were detected by flow cytometry. Selinexor inhibited the growth of Kasumi-1 cells at different time points in a concentration-dependent manner (r 24 h=0.7592, r 48 h=0.9456, and r 72 h=0.9425). Selinexor inhibited Kasumi-1 cells growth in a time-dependent manner (r =0.9057 in 2.5 μmol/L group, r =0.9897 in 5 μmol/L group and r =0.9994 in 10 μmol/L group). Selinexor could induce apoptosis of Kasumi-1 cells in a dose-dependent manner (r =0.9732), and the apoptosis of Kasumi-1 cells was more obvious with the increase of drug concentration. The proportion of G0/G1 phase was significantly increased and the proportion of S phase was significantly decreased after the treatment of Kasumi-1 cells by selinexor. With the increase of drug concentration, the proportion of Kasumi-1 cells cycle arrest in G0/G1 phase was increased and the cell synthesis was decreased. Selinexor can promote the death of tumor cells by inhibiting Kasumi-1 cells proliferation, inducing apoptosis and blocking cell cycle.

Unfolding the dynamics of ecosystems undergoing alternating wet-dry transitional states.

A significant fraction of Earth's ecosystems undergoes periodic wet-dry alternating transitional states. These globally distributed water-driven transitional ecosystems, such as intermittent rivers and coastal shorelines, have traditionally been studied as two distinct entities, whereas they constitute a single, interconnected meta-ecosystem. This has resulted in a poor conceptual and empirical understanding of water-driven transitional ecosystems. Here, we develop a conceptual framework that places the temporal availability of water as the core driver of biodiversity and functional patterns of transitional ecosystems at the global scale. Biological covers (e.g., aquatic biofilms and biocrusts) serve as an excellent model system thriving in both aquatic and terrestrial states, where their succession underscores the intricate interplay between these two states. The duration, frequency, and rate of change of wet-dry cycles impose distinct plausible scenarios where different types of biological covers can occur depending on their desiccation/hydration resistance traits. This implies that the distinct eco-evolutionary potential of biological covers, represented by their trait profiles, would support different functions while maintaining similar multifunctionality levels. By embracing multiple alternating transitional states as interconnected entities, our approach can help to better understand and manage global change impacts on biodiversity and multifunctionality in water-driven transitional ecosystems, while providing new avenues for interdisciplinary studies.