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Anemia has been a public health issue evoking global concern, and the low hemoglobin (Hb) concentration links to adverse pregnancy outcomes. However, the associations of PM2.5 and its constituents with Hb and anemia in pregnant women remain unclear. In this retrospective birth cohort study, 7932 pregnant women who delivered in the First Affiliated Hospital of Xi’an Jiaotong University from 2015 to 2018 were included. The Hb during the third trimester in pregnant women was assessed before delivery. PM2.5 and its constituents (BC, NH4+, NO3−, OM, SO42−, and Dust) during pregnancy were retrieved from the V4.CH.03 product constructed by the Atmospheric Composition Analysis Group. Generalized linear regression model was applied to investigate the effects of PM2.5 and its constituents on Hb and anemia during the third trimester in pregnant women. The means and standard deviations of PM2.5, BC, NH4+, NO3−, OM, SO42−, and Dust were 69.56 (15.24), 10.02 (2.72), 8.11 (1.77), 14.96 (5.42), 15.36 (4.11), 10.08 (1.20), and 10.98 (1.85) μg/m3, respectively. Per IQR increase (μg/m3) of PM2.5, BC, NO3−, and OM linked to − 0.75 (− 1.50, − 0.01), − 0.85 (− 1.65, − 0.04), − 0.79 (− 1.56, − 0.03), and − 0.73 (− 1.44, − 0.03) g/L decrease of Hb during the third trimester in multiparous pregnant women, but not for NH4+, SO42−, Dust, and primiparous pregnant women. PM2.5 and its constituents had no significant association with anemia, except for Dust (OR: 0.90, 95% CI: 0.82, 0.99, per IQR increase) in primiparous pregnant women. Besides, SO42− was of lag effects on Hb and anemia in multiparous pregnant women. Moreover, non-linear associations were found among PM2.5 and its constituents, Hb, and anemia. Therefore, exposure to PM2.5 and some constituents of PM2.5 was associated with reduced Hb level during the third trimester in multiparous pregnant women. Related departments and pregnant women should take targeted actions to eliminate the detrimental effects of PM2.5 and its constituents on pregnancy outcomes.

BackgroundBecause there is no exact therapeutic target, the systemic treatment of triple-negative breast cancer (TNBC) still relies on chemotherapy. In terms of local treatment, based on the highly malignant characteristics of TNBC, it is still uncertain whether patients should be given more aggressive local treatment.MethodsThis study was based on the SEER database. 13,262 TNBC patients undergoing chemotherapy were included. According to local treatment methods, patients were divided into breast-conserving surgery with radiotherapy (BCS + RT), total mastectomy alone and total mastectomy with radiotherapy (Mastectomy+RT). Kaplan-Meier survival analysis drew the survival curves of Overall Survival (OS) and Breast Cancer Specific Survival (BCSS), and Cox proportional risk regression models were used to analyze the impact of different local treatments on OS and BCSS.ResultsAfter adjusting confounding factors, Mastectomy alone group (HR = 1.57; 95%CI: 1.40–1.77) and Mastectomy+RT group (HR = 1.28; 95%CI: 1.12–1.46) were worse in OS than BCS + RT group, and Mastectomy+RT group (HR = 0.81; 95%CI: 0.73–0.91) was better in OS than Mastectomy alone group. The effect of local treatment for BCSS was similar to that of OS. After stratification according to age, tumor size and lymph node status, when the age was less than 55 years old, at T4, N2 or N3 category, there was no statistical significance between the BCS + RT group and the Mastectomy+RT group in OS or BCSS (allP > 0.05). When the age was less than 65 years old, at T1, T2 or N0 category, there was no statistical significance between the Mastectomy alone group and the Mastectomy+RT group in OS or BCSS (allP > 0.05). The results of other stratified analyses were basically consistent with the results of total population analysis.ConclusionThe survival benefit of breast-conserving surgery with radiotherapy was higher than or similar to that of total mastectomy TNBC patients.

Anemia has been a public health issue evoking global concern, and the low hemoglobin (Hb) concentration links to adverse pregnancy outcomes. However, the associations of PM

Mechanoreceptive organelles (MOs) are specialized subcellular entities in mechanoreceptors that transform extracellular mechanical stimuli into intracellular signals. Their ultrastructures are key to understanding the molecular nature and mechanics of mechanotransduction. Campaniform sensilla detect cuticular strain caused by muscular activities or external stimuli in Drosophila . Each campaniform sensillum has an MO located at the distal tip of its dendrite. Here we analyzed the molecular architecture of the MOs in fly campaniform mechanoreceptors using electron microscopic tomography. We focused on the ultrastructural organization of NompC (a force-sensitive channel) that is linked to the array of microtubules in these MOs via membrane-microtubule connectors (MMCs). We found that NompC channels are arranged in a regular pattern, with their number increasing from the distal to the proximal end of the MO. Double-length MMCs in nompC 29+29ARs confirm the ankyrin-repeat domain of NompC (NompC-AR) as a structural component of MMCs. The unexpected finding of regularly spaced NompC-independent linkers in nompC 3 suggests that MMCs may contain non-NompC components. Localized laser ablation experiments on mechanoreceptor arrays in halteres suggest that MMCs bear tension, providing a possible mechanism for why the MMCs are longer when NompC-AR is duplicated or absent in mutants. Finally, mechanical modeling shows that upon cuticular deformation, sensillar architecture imposes a rotational activating force, with the proximal end of the MO, where more NOMPC channels are located, being subject to larger forces than the distal end. Our analysis reveals an ultrastructural pattern of NompC that is structurally and mechanically optimized for the sensory functions of campaniform mechanoreceptors.

Low birth weight has long-term health effects, including neurodevelopmental delays, cardiovascular diseases, and type 2 diabetes, through epigenetic changes and modifications. Numerous studies have identified that PMA total of 8969 singleton live births born in 2015-2019 were included in this study. The inverse distance weighting method was applied to interpolate and calculate the average exposure to PMPer 10 μg/mPrenatal PM

More and more studies began to explore the hazardous health effects of PMIn this meta-analysis, we searched PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases for related articles written in English and published before October 18, 2020. Study selection was conducted according to the predetermined criteria and data attraction was done with predesigned form. A new instrument was applied to conduct the risk of bias assessment. And random-effect models were used to pool the estimates.A total of 3655 records were identified from the databases, but only 7 studies were ultimately included in this study. Positive association was found between the maternal exposure to PMMaternal exposure to PM

In mechanoreceptor cells, specialized cytoskeletons are formed at the site of mechanotransduction. Sun et al. reconstruct the microtubule-based cytoskeleton in fly campaniform mechanosensory cilia using electron microscopic tomography and establish dual functions for katanin p60-like 1 in shaping the cytoskeleton., Mechanoreceptor cells develop a specialized cytoskeleton that plays structural and sensory roles at the site of mechanotransduction. However, little is known about how the cytoskeleton is organized and formed. Using electron tomography and live-cell imaging, we resolve the 3D structure and dynamics of the microtubule-based cytoskeleton in fly campaniform mechanosensory cilia. Investigating the formation of the cytoskeleton, we find that katanin p60-like 1 (kat-60L1), a neuronal type of microtubule-severing enzyme, serves two functions. First, it amplifies the mass of microtubules to form the dense microtubule arrays inside the sensory cilia. Second, it generates short microtubules that are required to build the nanoscopic cytoskeleton at the mechanotransduction site. Additional analyses further reveal the functional roles of Patronin and other potential factors in the local regulatory network. In all, our results characterize the specialized cytoskeleton in fly external mechanosensory cilia at near-molecular resolution and provide mechanistic insights into how it is formed.

Background More and more studies began to explore the hazardous health effects of PM2.5, but few reported its impacts on stillbirth. The sparse results were inconsistent and remained to be integrated. Therefore, we aimed to reveal the association between maternal exposure to PM2.5 and stillbirth. Methods In this meta-analysis, we searched PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases for related articles written in English and published before October 18, 2020. Study selection was conducted according to the predetermined criteria and data attraction was done with predesigned form. A new instrument was applied to conduct the risk of bias assessment. And random-effect models were used to pool the estimates. Results A total of 3655 records were identified from the databases, but only 7 studies were ultimately included in this study. Positive association was found between the maternal exposure to PM2.5 (per 10 μg/m3 increased) in the entire pregnancy (OR: 1.15, 95% CI: 1.07–1.25) and third trimester (OR: 1.09, 95% CI: 1.01–1.18) and stillbirth, but the association between the maternal exposure to PM2.5 (per 10 μg/m3 increased) in the first trimester (OR: 1.01, 95% CI: 0.90–1.13) and second trimester (OR: 1.06, 95% CI: 0.98–1.14) and stillbirth was not statistically significant. Besides, there was no publication bias. Conclusions Maternal exposure to PM2.5 in the entire pregnancy and third trimester was associated with elevated risk of stillbirth. However, due to the high heterogeneity, further pathophysiological researches and high quality population studies were still warranted.

Mechanoreceptive organelles (MOs) are specialized subcellular entities in mechanoreceptors that transform extracellular mechanical stimuli into intracellular signals. Their ultrastructures are key to understanding the molecular nature and mechanics of mechanotransduction. Campaniform sensilla detect cuticular strain caused by muscular activities or external stimuli in Drosophila. Each campaniform sensillum has an MO located at the distal tip of its dendrite. Here we analyzed the molecular architecture of the MOs in fly campaniform mechanoreceptors using electron microscopic tomography. We focused on the ultrastructural organization of NompC (a force-sensitive channel) that is linked to the array of microtubules in these MOs via membrane-microtubule connectors (MMCs). We found that NompC channels are arranged in a regular pattern, with their number increasing from the distal to the proximal end of the MO. Double-length MMCs in nompC(29+29ARs) confirm the ankyrin-repeat domain of NompC (NompC-AR) as a structural component of MMCs. The unexpected finding of regularly spaced NompC-independent linkers in nompC(3) suggests that MMCs may contain non-NompC components. Localized laser ablation experiments on mechanoreceptor arrays in halteres suggest that MMCs bear tension, providing a possible mechanism for why the MMCs are longer when NompC-AR is duplicated or absent in mutants. Finally, mechanical modeling shows that upon cuticular deformation, sensillar architecture imposes a rotational activating force, with the proximal end of the MO, where more NOMPC channels are located, being subject to larger forces than the distal end. Our analysis reveals an ultrastructural pattern of NompC that is structurally and mechanically optimized for the sensory functions of campaniform mechanoreceptors.

In Chap. 3, we discussed the general physiology of fly mechanoreceptors. You may ask “well, these cells are sensitive to forces, but…how?” Great question! In Chap. 4, we will introduce the working mechanisms of several fly mechanoreceptors, including the bristle sensilla, campaniform sensilla, chordotonal organs, and class I–IV da neurons in fly larvae. We will cover the structural, mechanical, and molecular basis of mechanotransduction in these mechanoreceptors. On one hand, these mechanoreceptors share common structural designs, mechanical principles, and mechanotransduction molecules. On the other hand, they have also developed their own characters to fit the specific sensory functions. After reading this chapter, one might wonder about the stunning structure-mechanical design of the fly mechanoreceptors. Furthermore, these mechanoreceptors might share similar mechanics with the vertebrate or mammalian mechanoreceptors, so they provide great models to study the general principles in mechanotransduction.

In Chap. 4, we discussed the working mechanisms of several fly mechanoreceptors. These mechanoreceptors have developed striking structural-mechanical features that couple the environmental signals to the proximity of the mechanosensory cells. These proximal stimuli are then transformed by a transduction apparatus, often associated with the cell membrane, to the electrochemical signals in cells, which then initiates the neuronal impulses. In this chapter, we will discuss the core components of mechanotransduction apparatus at the molecular level, including the mechanotransduction channel and the gating spring. Two bona fide mechanotransduction channels are identified in Drosophila melanogaster, i.e., NompC/TRPN and DmPiezo. One molecular candidate for gating spring is identified, i.e., the ankyrin-repeat domain of NompC. In this chapter, we will introduce the structure, function, and physiology of these molecules and discuss their working mechanisms in fly mechanoreceptors.

As the start of this booklet, we begin this chapter by providing a definition on “what is mechanosensory transduction” at the cell biological level and listing the fundamental questions in this emerging field. We then briefly introduce “mechanotransduction in physiology” and “mechanotransduction in diseases,” which aim to integrate this cell biological process into the physiological and pathological contexts. Finally, we summarize the mechanotransduction processes in three model systems: (1) the bacterial cell, (2) the C. elegans touch-sensitive receptor, and (3) the vertebrate hair cell. We focus on how mechanotransduction contributes to the functions of these cells and the molecular basis of the mechanosensory transduction in each model cell.

In Chap. 1, we provided a general introduction for mechanotransduction. We feel that before going to the biological details (molecule, structures, etc.), it may help to provide the readers an overall picture on how an ideal system may work. We think that a theoretical model that depicts the operation of a mechanotransduction system may serve this purpose well. In this chapter, we introduce a classical model for cell mechanotransduction, i.e., the “gating-spring” model, which was proposed over 30 years ago based on the remarkable experimental work and data analysis on hair cells. We add some of our understanding of this model at the end of this chapter.

In Chaps. 1 and 2, we introduced the physiological roles of mechanotransduction and the conceptual design of a mechanoreceptor. How does a real mechanoreceptor look like and what are its specific functions in physiology? In this chapter, we provide the introduction for the specialized mechanoreceptors in Drosophila melanogaster, including their distributions, tissue/cellular organizations, and physiological functions. As shown in this chapter, the mechanosensory transduction is a fundamental process in the daily life of a fly, for example, in walking, standing, flying, crawling, jumping, hearing, defecation, mating, etc. The broad involvement of mechanotransduction in fly’s life makes the fly mechanoreceptors great models to study the molecular, structural, and mechanical basis of mechanotransduction.

This study describes a reliable protocol for callus induction and rapid mass propagation of the ecologically important plant, Zygophyllum xanthoxylon (Bunge) Maxim. The optimum callus induction medium was Murashige and Skoog (MS) supplemented with 4.4 μM 6-benzylaminopurine (BAP) and 2.7 μM α-naphthalene–acetic acid (NAA), on which the callus induction frequencies from different seedling explants were all 100%. However, seedling-derived callus did not form regenerated shoots. In order to achieve shoot multiplication, shoots were developed from cultured plumules, at an average of 3.1 shoots per explant, and the regenerated shoot tips were further multiplied by subculture. The best shoot multiplication from shoot tips was achieved on MS supplemented with 5.4 μM NAA and 22.2 μM BAP after 40 d of culture. Seventy-three percent of regenerated shoots formed roots when cultured on MS supplemented with 8.6 μM IAA after 4 wk of culture. The plants that acclimatized successfully in sand flourished the following year, with normal morphology and growth characteristics.