Predicting the Combined Effects of Multiple Stressors and Stress Adaptation in Gammarus pulex.

Global change confronts organisms with multiple stressors causing nonadditive effects. Persistent stress, however, leads to adaptation and related trade-offs. The question arises: How can the resulting effects of these contradictory processes be predicted? Here we show that Gammarus pulex from agricultural streams were more tolerant to clothianidin (mean EC50 148 µg/L) than populations from reference streams (mean EC50 67 µg/L). We assume that this increased tolerance results from a combination of physiological acclimation, epigenetic effects, and genetic evolution, termed as adaptation. Further, joint exposure to pesticide mixture and temperature stress led to synergistic interactions of all three stressors. However, these combined effects were significantly stronger in adapted populations as shown by the model deviation ratio (MDR) of 4, compared to reference populations (MDR = 2.7). The pesticide adaptation reduced the General-Stress capacity of adapted individuals, and the related trade-off process increased vulnerability to combined stress. Overall, synergistic interactions were stronger with increasing total stress and could be well predicted by the stress addition model (SAM). In contrast, traditional models such as concentration addition (CA) and effect addition (EA) substantially underestimated the combined effects. We conclude that several, even very disparate stress factors, including population adaptations to stress, can act synergistically. The strong synergistic potential underscores the critical importance of correctly predicting multiple stresses for risk assessment.

Combined impact of sleep and obesity on female infertility in the NHANES 2017-2020.

BACKGROUND: Sleep health and obesity may affect the risk of female infertility. However, few studies focused on the interaction of obesity and sleep health on the female infertility risk. This study aimed to evaluate the combined impact of trouble sleeping / sleep duration and overweight/obesity/ abdominal obesity on the risk of female infertility. METHODS: The data for this cross-sectional study was obtained from National Health and Nutritional Examination Survey, which provided information on trouble sleeping, sleep duration, overweight/obesity, abdominal obesity, and confounding factors. Adopted weighted univariate and multivariate logistic regression models to explore the relationship between trouble sleeping, sleep duration, overweight/obesity, abdominal obesity, and the risk of infertility, respectively, and the combined effect of trouble sleeping and overweight/obesity, trouble sleeping and abdominal obesity, sleep duration and overweight/obesity, sleep duration and abdominal obesity, on the female infertility risk. RESULTS: This study included a total of 1,577 women, and 191 were diagnosed with infertility. Women with infertility had a higher proportion of people with overweight/obesity, abdominal obesity, sleep duration ≤ 7 h and trouble sleeping than those with non-infertility. The result indicated that trouble sleeping [odds ratio (OR) = 2.25, 95% confidence intervals (CI): 1.49-3.39], sleep duration ≤ 7 h (OR = 1.59, 95% CI: 1.03-2.48), and the combined impact of abdominal obesity and trouble sleeping (OR = 2.18, 95% CI: 1.28-3.72), abdominal obesity and sleep duration ≤ 7 h (OR = 2.00, 95% CI: 1.17-3.40), overweight/obesity and trouble sleeping (OR = 2.29, 95% CI: 1.24-4.26), and overweight/obesity and sleep duration ≤ 7 h (OR = 1.88, 95% CI: 1.01-3.49) were associated with increased odds of infertility, respectively. CONCLUSION: There was combined effects of trouble sleeping/sleep duration ≤ 7 h and overweight/obesity/ abdominal obesity on increased odds of female infertility.

Patient mistreatment, social sharing of negative events and emotional exhaustion among Chinese nurses: the combined moderating effect of organizational support and trait resilience.

BACKGROUND: As a primary form of work-related violence in the healthcare sector, patient mistreatment negatively impacts nurses' well-being. To date, there has yet reached a definitive conclusion on the mediating mechanism and boundary conditions behind the influence of patient mistreatment on nurses' emotional exhaustion. METHODS: This study employed a convenience sampling method to recruit a sample of 1672 nurses from public hospitals in Western China. The data were collected through anonymous self-report questionnaires and analyzed using hierarchical regression and conditional processes to investigate a theoretical framework encompassing patient mistreatment, emotional exhaustion, social sharing of negative events, organizational support, and trait resilience. RESULTS: Patient mistreatment led to emotional exhaustion among nurses (ß = 0.625, p <.001), and social sharing of negative events mediated this positive relationship (effect = 0.073, SE = 0.013). The combined effects of organizational support and resilience moderated the mediating effect of the social sharing of negative events between patient mistreatment and emotional exhaustion (ß=-0.051, p <.05). Specifically, nurses with a high level of resilience would benefit from organizational support to alleviate emotional exhaustion caused by patient mistreatment. CONCLUSIONS: This study validated a significant positive association between patient mistreatment and emotional exhaustion, which aligns with previous research findings. Integrating conservation of resources theory and goal progress theory, we addressed previous contradictory findings on the impact of social sharing of negative events on emotional exhaustion. Social sharing of negative events served as a mediator between patient mistreatment and emotional exhaustion. Additionally, the moderating effect of organizational support on the relationship between social sharing of negative events and emotional exhaustion depended on individual trait of resilience.

Saturation response of enhanced vegetation productivity attributes to intricate interactions.

Evidence for the multifaceted responses of terrestrial ecosystems has been shown by the weakening of CO2 fertilization-induced and warming-controlled productivity gains. The intricate relationship between vegetation productivity and various environmental controls still remains elusive spatially. Here several inherent preponderances make China a natural experimental setting to investigate the interaction and relative contributions of five drivers to gross primary productivity for the period from 1982 to 2018 (i.e., elevated atmospheric CO2 concentrations, climate change, nutrient availability, anthropogenic land use change, and soil moisture) by coupling multiple long-term datasets. Despite a strikingly prominent enhancement of vegetation productivity in China, it exhibits similar saturation responses to the aforementioned environmental drivers (elevated CO2 , climatic factors, and soil moisture). The CO2 fertilization-dominated network explains the long-term variations in vegetation productivity in humid regions, but its effect is clearly attenuated or even absent in arid and alpine environments controlled by climate and soil moisture. Divergence in interactions also provides distinct evidence that water availability plays an essential role in limiting the potential effects of climate change and elevated CO2 concentrations on vegetation productivity. Unprecedented industrialization and dramatic surface changes may have breached critical thresholds of terrestrial ecosystems under the diverse natural environment and thus forced a shift from a period dominated by CO2 fertilization to a period with nonlinear interactions. These findings suggest that future benefits in terrestrial ecosystems are likely to be counteracted by uncertainties in the complicated network, implying an increasing reliance on human societies to combat potential risks. Our results therefore highlight the need to account for the intricate interactions globally and thus incorporate them into mitigation and adaptation policies.

Combined effects of ambient air pollution and PM2.5 components on renal function and the potential mediation effects of metabolic risk factors in China.

Growing evidence links long-term air pollution exposure with renal function. However, little research has been conducted on the combined effects of air pollutant mixture on renal function and multiple mediation effects of metabolic risk factors. This study enrolled 8996 adults without chronic kidney disease (CKD) at baseline from the CHCN-BTH cohort study. Three-year exposure to air pollutants [particulate matter ≤ 2.5 µm (PM2.5), PM10, PM1, ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO)] and PM2.5 components [black carbon (BC), ammonium (NH4+), nitrate (NO3-), sulfate (SO42-) and organic matter (OM)] were assessed using well-validated machine learning methods. Linear mixed models were applied to investigate the associations between air pollutants and estimated glomerular filtration rate (eGFR). Quantile G-computation was used to assess the combined effects of pollutant mixtures. Causal mediation analysis and Bayesian mediation analysis were employed to estimate the mediation effects of metabolic risk factors. An interquartile range increases in BC (-0.256, 95 %CI: -0.331, -0.180) and OM (-0.603, 95 %CI: -0.810, -0.397) were significantly associated with eGFR decline; while O3 (1.151, 95 %CI: 0.813, 1.489), PM10 (0.721, 95 %CI: 0.309, 1.133), NH4+ (0.990, 95 %CI: 0.638, 1.342), and NO3- (0.610, 95 %CI: 0.405, 0.815) were associated with higher eGFR. The combined effect of the PM2.5 component mixture was found to be associated with lower eGFR (-1.147, 95 % CI: -1.456, -0.839), with OM contributing 72.4 % of the negative effect. Univariate mediation analyses showed that high-density lipoprotein (HDL) mediated 7.1 %, 6.9 %, and 6.1 % effects of O3, BC, and OM, respectively. However, these mediation effects were not significant in Bayesian mediation analysis. These findings suggest the effect of the PM2.5 component mixture on eGFR decline and the strong contribution of OM. Metabolic risk factors may not mediate the effects of air pollutants. Further study is warranted to clarify the potential mechanisms involved.

Effects of Single and Combined Ciprofloxacin and Lead Treatments on Zebrafish Behavior, Oxidative Stress, and Elements Content.

Even though the toxic effects of antibiotics and heavy metals have been extensively studied in the last decades, their combined adverse impact on aquatic organisms is poorly understood. Therefore, the objective of this study was to assess the acute effects of a ciprofloxacin (Cipro) and lead (Pb) mixture on the 3D swimming behavior, acetylcholinesterase (AChE) activity, lipid peroxidation level (MDA-malondialdehyde), activity of some oxidative stress markers (SOD-superoxide dismutase and GPx-glutathione peroxidase), and the essential elements content (Cu-copper, Zn-zinc, Fe-iron, Ca-calcium, Mg-magnesium, Na-sodium and K-potassium) in the body of zebrafish (Danio rerio). For this purpose, zebrafish were exposed to environmentally relevant concentrations of Cipro, Pb, and a mixture for 96 h. The results revealed that acute exposure to Pb alone and in mixture with Cipro impaired zebrafish exploratory behavior by decreasing swimming activity and elevating freezing duration. Moreover, significant deficiencies of Ca, K, Mg, and Na contents, as well as an excess of Zn level, were observed in fish tissues after exposure to the binary mixture. Likewise, the combined treatment with Pb and Cipro inhibited the activity of AChE and increased the GPx activity and MDA level. The mixture produced more damage in all studied endpoints, while Cipro had no significant effect. The findings highlight that the simultaneous presence of antibiotics and heavy metals in the environment can pose a threat to the health of living organisms.

Responses of soil fauna communities to the individual and combined effects of multiple global change factors.

Soil fauna plays a key role in regulating biogeochemical cycles, but how multiple global change factors (GCFs) may affect faunal communities remains poorly studied. We conducted a meta-analysis using 1154 observations to evaluate the individual and combined effects of elevated CO2 , nitrogen (N) addition, warming, increased rainfall and drought on soil fauna density and diversity. Here we show that, overall, individual and combined effects of GCFs had negligible effects on soil fauna density and diversity, except that density was negatively affected by drought (-27.4%) and positively affected by increased rainfall individually (+24.9%) and in combination with N addition (+67.3%) or warming (+70.4%). GCF effects varied among taxonomic groups both in magnitude and direction. Variables such as latitude, elevation and experimental setting significantly impacted both individual and combined effects. Our results suggest that soil fauna density is affected by changed rainfall regimes, while diversity is resistant against individual and combined effects of multiple GCFs.

Combined effects of heatwaves and micropollutants on freshwater ecosystems: Towards an integrated assessment of extreme events in multiple stressors research.

Freshwater ecosystems are strongly influenced by weather extremes such as heatwaves (HWs), which are predicted to increase in frequency and magnitude in the future. In addition to these climate extremes, the freshwater realm is impacted by the exposure to various classes of chemicals emitted by anthropogenic activities. Currently, there is limited knowledge on how the combined exposure to HWs and chemicals affects the structure and functioning of freshwater ecosystems. Here, we review the available literature describing the single and combined effects of HWs and chemicals on different levels of biological organization, to obtain a holistic view of their potential interactive effects. We only found a few studies (13 out of the 61 studies included in this review) that investigated the biological effects of HWs in combination with chemical pollution. The reported interactive effects of HWs and chemicals varied largely not only within the different trophic levels but also depending on the studied endpoints for populations or individuals. Hence, owing also to the little number of studies available, no consistent interactive effects could be highlighted at any level of biological organization. Moreover, we found an imbalance towards single species and population experiments, with only five studies using a multitrophic approach. This results in a knowledge gap for relevant community and ecosystem level endpoints, which prevents the exploration of important indirect effects that can compromise food web stability. Moreover, this knowledge gap impairs the validity of chemical risk assessments and our ability to protect ecosystems. Finally, we highlight the urgency of integrating extreme events into multiple stressors studies and provide specific recommendations to guide further experimental research in this regard.

Interactions of the chemokines CXCL11 and CXCL12 in human tumor cells.

BACKGROUND: The chemokines, CXCL12 and CXCL11, are upregulated in tumors from many organs and control their progression. CXCL12 and CXCL11 affect tumor cell functions by either binding their prime receptors, CXCR4 and CXCR3, respectively, and/or CXCR7 as a common second chemokine receptor. In humans, CXCR3 exists in the functional splice variants, CXCR3A and CXCR3B, which either have pro- or anti-tumor activity, respectively. Despite the intimate crosstalk between the CXCL12- and CXCL11-system, the impact of a combination of CXCL12 and CXCL11 on tumor progression remains vague. METHODS: In the present work, we have analyzed CXCL12 and CXCL11 for combined effects on migration, invasion, proliferation, and cytostatic-induced apoptosis of the human tumor cells, A549, A767, A772, DLD-1, and MDA-MB-231. RESULTS: We demonstrate that the mode of interaction differs with respect to cell type and function and allows for either potentiation, attenuation or no changes of cellular responses. The divergent responses are not the result of the distinct use of different CXCL12- and CXCL11-receptors by the respective tumor cells, but in case of cell migration seem to be associated with the activation of p38 signaling pathways. CONCLUSIONS: Our findings point to therapeutic limitations of ongoing efforts to selectively target CXCR3, CXCR4, or CXCR7 in cancer patients, and rather favor individualized targeting strategies.

Co-exposure of zinc oxide nanoparticles and multi-layer graphenes in blackfish (Capoeta fusca): evaluation of lethal, behavioural, and histopathological effects.

Zinc oxide nanoparticles (ZnO NPs) and multi-layer graphenes (MLGs) are widely used, and due to the lack of appropriate wastewater treatment may end up in the aquatic environment, with unknown consequences to biota. The main purpose of this study was to assess the acute toxicity, histopathological and behavioural changes caused by the exposure of ZnO NPs and MLGs, alone and combined, to the blackfish Capoeta fusca. The estimated mean 96 h-LC50 for ZnO NPs was 4.9 mg L-1 and 68.4 mg L-1 for MLGs. In combination, MLGs increased the acute toxicity of the ZnO NPs. The effects of the different NPs on the gills included hyperplasia, aneurisms, and fusion of the lamellae. In the intestine, exposure to the NPs resulted in an increase in the number and swelling of goblet cells and tissue degeneration. Loss of balance, restlessness, erratic and abnormal swimming patterns were the most common behavioural changes seen in the ZnO NPs' exposed blackfish. In contrast with the acute toxicity findings, MLGs decreased the histopathological and behavioural effects of the ZnO NPs on both gills and intestinal tissues as well as fish behaviour. Our experimental results illustrated insights into the simultaneous exposure assessment of metal-based NPs and carbon nanomaterials, although further research is needed on the interactions exposure of these substances to interpreting the toxicological effects of metal-based nanomaterials seen in exposed organisms.

Effect of Sex on Structural and Morphological Parameters of Rat Heart under Conditions of Combined Exposure to Hypokinesia and Cold.

We studied the combined effect of hypokinesia and external cooling on structural and morphological changes in the ventricular myocardium and parameters of homeostasis of the blood system in male and female WKY (normotensive) and SHR (hypertensive) rats. Simultaneous exposure to hypokinesia and cold caused destructive processes in the myocardium and high dynamics of heart remodeling with diverse structural and morphological changes in the left ventricle in rats of both sexes. The thickness of the left ventricular wall most rapidly decreased in male hypertensive SHR rats. The thickness of the wall of the right ventricle significantly increased in male and female rats of both strains. In WKY and SHR females, structural transformations in the heart were less pronounced than in males. The key role in different degree of morphological remodeling of the myocardium in male and female probably belongs to sex hormones.

Combined secondary compounds naturally found in nectars enhance honeybee cognition and survival.

The alkaloid caffeine and the amino acid arginine are present as secondary compounds in nectars of some flower species visited by pollinators. Each of these compounds affects honeybee appetitive behaviours by improving foraging activity and learning. While caffeine potentiates responses of mushroom body neurons involved in honeybee learning processes, arginine acts as precursor of nitric oxide, enhancing the protein synthesis involved in memory formation. Despite existing evidence on how these compounds affect honeybee cognitive ability individually, their combined effect on this is still unknown. We evaluated acquisition and memory retention in a classical olfactory conditioning procedure, in which the reward (sucrose solution) contained traces of caffeine, arginine or a mixture of the two. The results indicate that the presence of the single compounds and their most concentrated mixture increases bees' learning performance. However, memory retention, measured in the short and long term, increases significantly only in those treatments offering combinations of the two compounds in the reward. Additionally, the most concentrated mixture triggers a significant survival rate in the conditioned bees. Thus, some nectar compounds, when combined, show synergistic effects on cognitive ability and survival in an insect.

Effects of exposure to surrounding green, air pollution and traffic noise with non-accidental and cause-specific mortality in the Dutch national cohort.

BACKGROUND: Everyday people are exposed to multiple environmental factors, such as surrounding green, air pollution and traffic noise. These exposures are generally spatially correlated. Hence, when estimating associations of surrounding green, air pollution or traffic noise with health outcomes, the other exposures should be taken into account. The aim of this study was to evaluate associations of long-term residential exposure to surrounding green, air pollution and traffic noise with mortality. METHODS: We followed approximately 10.5 million adults (aged ≥ 30 years) living in the Netherlands from 1 January 2013 until 31 December 2018. We used Cox proportional hazard models to evaluate associations of residential surrounding green (including the average Normalized Difference Vegetation Index (NDVI) in buffers of 300 and 1000 m), annual average ambient air pollutant concentrations [including particulate matter (PM2.5), nitrogen dioxide (NO2)] and traffic noise with non-accidental and cause-specific mortality, adjusting for potential confounders. RESULTS: In single-exposure models, surrounding green was negatively associated with all mortality outcomes, while air pollution was positively associated with all outcomes. In two-exposure models, associations of surrounding green and air pollution attenuated but remained. For respiratory mortality, in a two-exposure model with NO2 and NDVI 300 m, the HR of NO2 was 1.040 (95%CI: 1.022, 1.059) per IQR increase (8.3 µg/m3) and the HR of NDVI 300 m was 0.964 (95%CI: 0.952, 0.976) per IQR increase (0.14). Road-traffic noise was positively associated with lung cancer mortality only, also after adjustment for air pollution or surrounding green. CONCLUSIONS: Lower surrounding green and higher air pollution were associated with a higher risk of non-accidental and cause-specific mortality. Studies including only one of these correlated exposures may overestimate the associations with mortality of that exposure.

Does thermal control improve visual satisfaction? Interactions between occupants' self-perceived control, visual, thermal, and overall satisfaction.

Occupants' satisfaction had been researched independently related to thermal and visual stimuli for many decades showing among others the influence of self-perceived control. Few studies revealed interactions between thermal and visual stimuli affecting occupant satisfaction. In addition, studies including interactions between thermal and visual stimuli are lacking different control scenarios. This study focused on the effects of thermal and visual factors, their interaction, seasonal influences, and the degree of self-perceived control on overall, thermal, and visual satisfaction. A repeated-measures laboratory study with 61 participants running over two years and a total of 986 participant sessions was conducted. Mixed model analyses with overall satisfaction as outcome variable revealed that thermal satisfaction and visual satisfaction are the most important predictors for overall satisfaction with the indoor environment. Self-perceived thermal control served as moderator between thermal satisfaction and overall satisfaction. Season had slight influence on overall satisfaction. Random effects explained the highest amount of variance, indicating that intra- and interindividual differences in the ratings of satisfaction are more prevalent than study condition. Future building design and operation plans aiming at a high level of occupant satisfaction should consider personal control opportunities and take into account the moderating effect of control opportunities in multimodal interactions.

Blood deprivation and heat stress increase mortality in bed bugs (Cimex lectularius) exposed to insect pathogenic fungi or desiccant dust.

Bed bugs (Cimex lectularius L.) have returned as a nuisance pest in the last 20 years. Different bed bug control measures in combination have not been thoroughly studied, although induction of multiple stressors may improve extermination. The effects of heat stress only, heat stress followed by exposure to insect pathogenic fungi, and heat stress followed by exposure to desiccant dust on starved and blood-fed bed bugs were investigated. Five days at 22 °C (control), 32 °C, 34 °C, or 36 °C (heat stress) did not cause mortality in adults. However, their starved first instar nymphs produced after heat stress suffered mortalities of 33%, 56% and 100%, respectively. Exposure to insect pathogenic fungi after heat stress increased the mortality of adults and their progeny compared to exposure to fungi without heat stress. The beneficial effects of heat stress were not observed in blood-fed bed bugs. Desiccant dust killed all nymphs within 2 days and all adults within 3 days regardless of previous heat stress, but survival time was prolonged by access to blood. This study highlights the advantage of combining different methods in pest management, and points to heat stress combined with blood deprivation as possible management elements to increase the control success.

Temperature-Color Interaction: Subjective Indoor Environmental Perception and Physiological Responses in Virtual Reality.

OBJECTIVE: Temperature-color interaction effects on subjective perception and physiological responses are investigated using a novel hybrid experimental method combining thermal and visual stimuli from real and virtual reality (VR) environments, respectively. BACKGROUND: Despite potential building design applications, studies combining temperature with daylight transmitted through colored glazing are limited due to hard-to-control light conditions. VR is identified as a promising experimental tool for such investigations that overcomes the limitations of experiments using daylight. METHOD: Fifty-seven people participated in an experiment combining three colored glazing (orange/blue/neutral) and two temperatures (24°C/29°C). Exposed to one color-temperature combination, participants evaluated their thermal, visual, and overall perception, whereas their physiological responses (heart rate, skin conductance, and skin temperature) were continuously measured. RESULTS: Daylight color significantly affected thermal perception, whereas no significant effects of temperature on visual perception were found. Acceptability of the workspace was affected by both color and temperature. Cross-modal effects from either daylight color or temperature levels on physiological responses were not observed. CONCLUSION: In the VR setting, the orange daylight led to warmer thermal perception in (close-to-) comfortable temperatures, resulting in a color-induced thermal perception and indicating that orange glazing should be used with caution in a slightly warm environment. APPLICATION: Findings can be applied to the design of buildings using new glazing technologies with saturated colors, such as transparent photovoltaics. Despite some limitations, the hybrid environment is suggested as a promising experimental tool for future studies on indoor factor interactions.

In Vitro Evaluation of the Individual and Combined Cytotoxic and Estrogenic Effects of Zearalenone, Its Reduced Metabolites, Alternariol, and Genistein.

Mycotoxins are toxic metabolites of filamentous fungi. Previous studies demonstrated the co-occurrence of Fusarium and Alternaria toxins, including zearalenone (ZEN), ZEN metabolites, and alternariol (AOH). These xenoestrogenic mycotoxins appear in soy-based meals and dietary supplements, resulting in the co-exposure to ZEN and AOH with the phytoestrogen genistein (GEN). In this study, the cytotoxic and estrogenic effects of ZEN, reduced ZEN metabolites, AOH, and GEN are examined to evaluate their individual and combined impacts. Our results demonstrate that reduced ZEN metabolites, AOH, and GEN can aggravate ZEN-induced toxicity; in addition, the compounds tested exerted mostly synergism or additive combined effects regarding cytotoxicity and/or estrogenicity. Therefore, these observations underline the importance and the considerable risk of mycotoxin co-exposure and the combined effects of mycoestrogens with phytoestrogens.

Towards a unified study of multiple stressors: divisions and common goals across research disciplines.

Anthropogenic environmental changes, or 'stressors', increasingly threaten biodiversity and ecosystem functioning worldwide. Multiple-stressor research is a rapidly expanding field of science that seeks to understand and ultimately predict the interactions between stressors. Reviews and meta-analyses of the primary scientific literature have largely been specific to either freshwater, marine or terrestrial ecology, or ecotoxicology. In this cross-disciplinary study, we review the state of knowledge within and among these disciplines to highlight commonality and division in multiple-stressor research. Our review goes beyond a description of previous research by using quantitative bibliometric analysis to identify the division between disciplines and link previously disconnected research communities. Towards a unified research framework, we discuss the shared goal of increased realism through both ecological and temporal complexity, with the overarching aim of improving predictive power. In a rapidly changing world, advancing our understanding of the cumulative ecological impacts of multiple stressors is critical for biodiversity conservation and ecosystem management. Identifying and overcoming the barriers to interdisciplinary knowledge exchange is necessary in rising to this challenge. Division between ecosystem types and disciplines is largely a human creation. Species and stressors cross these borders and so should the scientists who study them.

[Occurrence and related factors of preterm birth in Guangxi Zhuang Autonomous Region during 2017-2019].

Objective: To investigate the incidence of preterm birth in Guangxi Zhuang Autonomous Region and explore the related factors and their combined effects. Methods: The study subjects were women giving birth to live babies at the monitoring points of critical maternal hospital monitoring system in Guangxi Zhuang Autonomous Region from January 1, 2017 to December 31, 2019. The data of general characteristics (age and marital status), pregnancies (parity, number of previous cesarean delivery, the number of prenatal check and number of fetuses in this pregnancy) and disease conditions (placenta previa, placental abruption, hypertension, diabetes, anemia, and heart disease) were collected, and the incidence of preterm birth were calculated according to the definition of preterm birth set by WHO and China, respectively. Logistic regression model was used to explore the factors associated with premature birth and their combined effects. Results: According to definitions of WHO and China, the cumulative incidence of preterm birth in Guangxi from 2017 to 2019 was 7.45% (16 819/225 727) and 7.34% (16 559/225 727), respectively. Advanced age [≤34 years old as reference, OR (95%CI) of 35-39 and ≥40 years old were 1.36 (1.30-1.42) and 1.61 (1.50-1.74), respectively], unmarried (including divorced or widowed) [OR (95%CI): 1.28 (1.17-1.40)], primiparae [OR (95%CI): 1.34 (1.29-1.40)], previous cesarean section [no previous cesarean section as reference, OR (95%CI) of 1 and ≥2 times of previous cesarean section were 1.30 (1.24-1.36) and 1.85 (1.65-2.08), respectively], antenatal examination<8 [OR (95%CI): 2.72 (2.62-2.81)], multiple pregnancies [OR (95%CI): 15.00 (14.01-16.06)], placenta previa [OR (95%CI): 6.90 (6.35-7.50)], placental abruption [OR (95%CI): 8.18 (7.36-9.10)], gestational hypertension [OR (95%CI): 2.29 (2.17-2.42)], gestational diabetes mellitus [OR (95%CI): 1.43 (1.37-1.49)], anemia [OR (95%CI): 1.10 (1.07-1.14)], and heart diseases [OR (95%CI): 2.98(2.43-3.65)] were all positively correlated with preterm birth. The risk of preterm birth in pregnant women exposed to 1, 2, 3, 4, 5, 6 and ≥7 preterm birth related factors was 1.51, 2.29, 4.49, 9.69, 20.87, 46.88 and 192.11 times that of non-exposed women, respectively (all P values<0.001). Conclusion: Preterm birth is associated with maternal general characteristics, pregnancy and disease status, and the combined effect of preterm birth related factors significantly increases the risk of preterm birth.

A comparison between the combined effect of calcium carbonate with sucroferric oxyhydroxide and other phosphate binders: an in vitro and in vivo experimental study.

BACKGROUND: Approximately 30% of patients on dialysis received combination therapy for their phosphate binder prescription; however, few studies for combined effects of phosphate binders are reported. For the purpose of evaluating the efficacy of combination therapy, we compared the efficacy of sucroferric oxyhydroxide (PA21) combined with calcium carbonate with that of lanthanum carbonate hydrate, sevelamer hydrochloride, and ferric citrate hydrate combined with calcium carbonate. METHODS: For in vitro studies, calcium carbonate and the other phosphate binders alone or in combination were stirred in phosphate solution at pH 2-8 for 2 h. After centrifuging the suspension, the phosphorus level in the supernatant was determined. For in vivo studies, rats were orally administered calcium carbonate and the other phosphate binders (except for sevelamer hydrochloride) alone or in combination, followed by oral administration of phosphate solution adjusted to pH 2 or 7. Serum samples were collected from the rats at predetermined timepoints and the serum phosphorus levels were determined and analyzed using a two-way analysis of variance. RESULTS: In the in vitro study, the measured phosphate-binding capacity of combining sevelamer hydrochloride, PA21, and lanthanum carbonate hydrate with calcium carbonate was approximately equal to or greater than the theoretical values under most conditions. Furthermore, these combined effects were insensitive to pH in that order. The measured phosphate-binding capacity of ferric citrate hydrate combined with calcium carbonate was smaller than the theoretical values, and the combination did not exhibit efficacy under any of the tested conditions. In the in vivo study, the combined effect of PA21 and calcium carbonate at both pH values and that of lanthanum carbonate hydrate and calcium carbonate at pH 2 were additive. In contrast, the combined effect of lanthanum carbonate hydrate and calcium carbonate at pH 7 and that of ferric citrate hydrate and calcium carbonate at pH 2 were antagonistic. CONCLUSIONS: These results suggest that coadministration of PA21 and calcium carbonate showed good and relatively stable efficacy throughout the range of the gastrointestinal pH and that combining lanthanum carbonate hydrate and ferric citrate hydrate with calcium carbonate may not produce the expected efficacy under certain conditions.