Although cryopreservation has been developed and optimized over the past decades, it causes various stresses, including cold shock, osmotic stress, and ice crystal formation, thereby reducing ...fertility. During cryopreservation, addition of cryoprotective agent (CPA) is crucial for protecting spermatozoa from freezing damage. However, the intrinsic toxicity and osmotic stress induced by CPA cause damage to spermatozoa. To identify the effects of CPA addition during cryopreservation, we assessed the motility (%), motion kinematics, capacitation status, and viability of epididymal spermatozoa using computer-assisted sperm analysis and Hoechst 33258/chlortetracycline fluorescence staining. Moreover, the effects of CPA addition were also demonstrated at the proteome level using two-dimensional electrophoresis. Our results demonstrated that CPA addition significantly reduced sperm motility (%), curvilinear velocity, viability (%), and non-capacitated spermatozoa, whereas straightness and acrosome-reacted spermatozoa increased significantly (p < 0.05). Ten proteins were differentially expressed (two decreased and eight increased) (>3 fold, p < 0.05) after CPA, whereas NADH dehydrogenase flavoprotein 2, f-actin-capping protein subunit beta, superoxide dismutase 2, and outer dense fiber protein 2 were associated with several important signaling pathways (p < 0.05). The present study provides a mechanistic basis for specific cryostresses and potential markers of CPA-induced stress. Therefore, these might provide information about the development of safe biomaterials for cryopreservation and basic ground for sperm cryopreservation.
MicroRNA (miRNA) maturation is initiated by Microprocessor composed of RNase III DROSHA and its cofactor DGCR8, whose fidelity is critical for generation of functional miRNAs. To understand how ...Microprocessor recognizes pri-miRNAs, we here reconstitute human Microprocessor with purified recombinant proteins. We find that Microprocessor is an ∼364 kDa heterotrimeric complex of one DROSHA and two DGCR8 molecules. Together with a 23-amino acid peptide from DGCR8, DROSHA constitutes a minimal functional core. DROSHA serves as a “ruler” by measuring 11 bp from the basal ssRNA-dsRNA junction. DGCR8 interacts with the stem and apical elements through its dsRNA-binding domains and RNA-binding heme domain, respectively, allowing efficient and accurate processing. DROSHA and DGCR8, respectively, recognize the basal UG and apical UGU motifs, which ensure proper orientation of the complex. These findings clarify controversies over the action mechanism of DROSHA and allow us to build a general model for pri-miRNA processing.
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•Microprocessor is a trimeric complex with one DROSHA and two DGCR8•Functional core of Microprocessor contains DROSHA and the C-terminal tail of DGCR8•DROSHA serves as a ruler by recognizing the basal elements•DGCR8 interacts with the apical elements to ensure fidelity of processing
Functional reconstruction of human Microprocessor defines its molecular stoichiometry and the specific role of each component in substrate recognition and orientation, revealing a comprehensive processing mechanism of Microprocessor.
Biocompatibility is important for the 3D printing of resins used in medical devices and can be affected by photoinitiators, one of the key additives used in the 3D printing process. The choice of ...ingredients must be considered, as the toxicity varies depending on the photoinitiator, and unreacted photoinitiator may leach out of the polymerized resin. In this study, the use of ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate (TPO-L) as a photoinitiator for the 3D printing of resin was considered for application in medical device production, where the cytotoxicity, colour stability, dimensional accuracy, degree of conversion, and mechanical/physical properties were evaluated. Along with TPO-L, two conventional photoinitiators, phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide (BAPO) and diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO), were considered. A total of 0.1 mol% of each photoinitiator was mixed with the resin matrix to prepare a resin mixture for 3D printing. The specimens were printed using a direct light processing (DLP) type 3D printer. The 3D-printed specimens were postprocessed and evaluated for cytotoxicity, colour stability, dimensional accuracy, degree of conversion, and mechanical properties in accordance with international standards and the methods described in previous studies. The TPO-L photoinitiator showed excellent biocompatibility and colour stability and possessed with an acceptable dimensional accuracy for use in the 3D printing of resins. Therefore, the TPO-L photoinitiator can be sufficiently used as a photoinitiator for dental 3D-printed resin.
Introduction
To devise appropriate preventive strategies after stroke, knowledge of the association between post-stroke cognitive impairment (PSCI) and prognosis of stroke patients is important. We ...investigated the association between PSCI and the vascular outcomes in patients with ischemic stroke with best medical care considering their risk factors and adherence to medications.
Methods
Of the 1534 ischemic stroke patients who randomly assigned to aspirin or cilostazol treatment with best medical therapy by the PICASSO (PreventIon of CArdiovascular events in iSchemic Stroke patients with high risk of cerebral hemOrrhage) trial, 1240 with baseline mini-mental state examination (MMSE) scores were analysed retrospectively. The patients were classified into three groups based on MMSE scores. Recurrence of ischemic stroke, stroke of any type and composite of major vascular events were compared among them.
Results
Of the 1240 patients, 376 had MMSE scores of 28–30 (highest tertile), 419 had scores of 24–27 (middle tertile) and 445 had scores of 0–23 (lowest tertile). The average time from stroke onset to MMSE examination was 31.8 days. By trend analysis, lower tertile of MMSE score was significantly associated with recurrent ischemic stroke (
p
= 0.0017), stroke of any type (
p
= 0.0053) and composite vascular outcome (
p
= 0.0122). After adjustment for covariates, PSCI was independently associated with risk of recurrent ischemic stroke (HR 2.40, 95% confidence interval 1.12–5.14).
Conclusions
Cognitive impairment was associated with recurrence of ischemic stroke in high risk patients during adequate medical therapy including antiplatelet therapy. However, the other vascular events were not.
Bioprosthetic valves are employed to replace defective heart valves. However, structural degeneration is prevalent in bioprosthetic valves because the heart valve leaflets are exposed to extreme and ...repetitive cardiovascular pressure. Herein, a silk fibroin‐based heart valve leaflet, which executes the physiological role of a heart valve, is developed. To this end, a templated assembly technology is developed. Notably, a physically optimal hierarchical structure for replacing the natural heart valve leaflet is realized by numerous firmly stacked β‐sheet crystals distributed within collective tyrosine‐reinforcing amorphous strands. Almost half (46.9%) of the silk fibroin‐based heart valve leaflet comprises strongly stacked β‐sheet crystals, leading to a 292% enhancement in stacking strength. The templated assembly results in the entanglement of amorphous strands, upregulating the non‐covalent interactions within the tyrosine. Consequently, the strength is enhanced by 1380% compared to native silk fibroin. Moreover, the templated assembly enhances the static and dynamic mechanical properties, thereby delivering a desirable performance for its use in heart valve replacement. Interestingly, the aortic valve composed of silk fibroin‐based leaflets does not fail under the cardiovascular pressure of 60–180 mmHg. Furthermore, the valve performance is satisfactory and surmounts the requirements of the industrial standard ISO 5840.
Silk fibroin‐based heart valve leaflet (SLEAF) is prepared by developing the templated assembly technology. In particular, SLEAF comprises numerous firmly stacked β‐sheet crystals distributed within collective tyrosine‐reinforcing amorphous strands. SLEAF presents the mechanical properties desirable for heart valve replacement. SLEAF‐based bioprosthetic aortic valve (SLEAF‐AV) shows superior durability and valvular performance fulfilling the industrial standard.
Herein we evaluate the effect of nanodiamond (ND) incorporation on the mechanical properties of poly(methyl methacrylate) (PMMA) nanocomposite. Three quantities of ND (0.1, 0.3, and 0.5 wt.%) were ...tested against the control and zirconium oxide nanoparticles (ZrO). Flexural strength and elastic modulus were measured using a three-point bending test, surface hardness was evaluated using the Vickers hardness test, and surface roughness was evaluated using atomic force microscopy (AFM), while fungal adhesion and viability were studied using Candida albicans. Samples were also analyzed for biofilm thickness and biomass in a saliva-derived biofilm model. All groups of ND-PMMA nanocomposites had significantly greater mean flexural strengths and statistically improved elastic modulus, compared to the control and ZrO groups (P < 0.001). The Vickers hardness values significantly increased compared to the control group (P < 0.001) with 0.3% and 0.5% ND. ND addition also gave significant reduction in fungal adhesion and viability (P < 0.001) compared to the control group. Finally, salivary biofilm formation was markedly reduced compared to the ZrO group. Hence, the incorporation of 0.1–0.5 wt.% ND with auto- polymerized PMMA resin significantly improved the flexural strength, elastic modulus, and surface hardness, and provided considerable fungal resistance.
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•Confirmed the world's longest man-made dike impact on tidal flat food web dynamics.•Revealed eutrophic water discharge impact on the nutritional and microalgal ...distribution.•Characterized the greater MPB contribution to benthos by eutrophic water input.•Identified distinct discharge water impact on diet utilization of filter/deposit feeders.
The man-made sea dike has disrupted the natural link between riverine and marine ecosystems and caused eutrophication within the aquatic ecosystem. The eutrophic water discharge has also raised concerns. As a representative tidal flat with the longest dike in the world, Saemangeum has experienced the problem of eutrophication. To elucidate the discharge water effects on the benthic food web dynamics, a four-year round sampling was conducted in/outside of the Saemangeum sea dike. Stable isotope analysis was applied to benthos (a total of 54 species) and their potential diets. Water discharge tripled in period II (2021–2022) compared to the period I (2019–2020). However, there were no significant impact changes in food web structure between the two periods due to improved lake water quality in period II. A positive correlation of nutrient concentration between the inner and outer areas of the dike revealed a direct effect of the water discharge on the outer tidal flat. The water discharge altered the spatial environmental conditions and the food web structure of the outer tidal flat. High TN concentrations stimulated the biomass of microphytobenthos (MPB) near the water gates, which in turn increased MPB consumption by benthos, demonstrating the in/direct impacts of water discharge on the food web. Furthermore, filter feeders exhibited a more sensitive response to spatial organic matter distribution compared to deposit feeders in diet utilization. Overall, our novel findings on food web dynamics in a representative tidal flat with artificial structures emphasize the necessity of continuous monitoring to ensure the sustainability of coastal ecosystems.
Maternal exposure to the endocrine disruptor bisphenol A (BPA) has been linked to offspring reproductive abnormalities. However, exactly how BPA affects offspring fertility remains poorly understood.
...The aim of the present study was to evaluate the effects of gestational BPA exposure on sperm function, fertility, and proteome profile of F1 spermatozoa in adult mice.
Pregnant CD-1 mice (F0) were gavaged with BPA at three different doses (50 μg/kg bw/day, 5 mg/kg bw/day, and 50 mg/kg bw/day) on embryonic days 7 to 14. We investigated the function, fertility, and related processes of F1 spermatozoa at postnatal day 120. We also evaluated protein profiles of F1 spermatozoa to monitor their functional affiliation to disease.
BPA inhibited sperm count, motility parameters, and intracellular ATP levels in a dose-dependent manner. These effects appeared to be caused by reduced numbers of stage VIII seminiferous epithelial cells in testis and decreased protein kinase A (PKA) activity and tyrosine phosphorylation in spermatozoa. We also found that BPA compromised average litter size. Proteins differentially expressed in spermatozoa from BPA treatment groups are known to play a critical role in ATP generation, oxidative stress response, fertility, and in the pathogenesis of several diseases.
Our study provides mechanistic support for the hypothesis that gestational exposure to BPA alters sperm function and fertility via down-regulation of tyrosine phosphorylation through a PKA-dependent mechanism. In addition, we anticipate that the BPA-induced changes in the sperm proteome might be partly responsible for the observed effects in spermatozoa. Citation: Rahman MS, Kwon WS, Karmakar PC, Yoon SJ, Ryu BY, Pang MG. 2017. Gestational exposure to bisphenol-A affects the function and proteome profile of F1 spermatozoa in adult mice. Environ Health Perspect 125:238-245; http://dx.doi.org/10.1289/EHP378.
Background
Macrolide antibiotics are widely used to treat various infections such as pneumonia and sinusitis, and previous exposure to macrolides is presumed to be a risk factor for standard triple ...therapy failure in Helicobacter pylori (H. pylori) eradication. We aimed to determine whether previous use of macrolide antibiotics could affect clarithromycin resistance of H. pylori.
Materials and methods
From the Korea National Health Insurance Service (NHIS2021‐1‐775) database, a total of 46,160 patients who were tested for clarithromycin resistance of H. pylori from 2016 to 2019 in Korea were identified. Their history of antibiotics in the past 10 years and history of respiratory comorbidity in the past 1 year were investigated.
Results
Clarithromycin resistance rate of H. pylori in Korea was 16.2%. A multivariate analysis revealed that female sex (OR: 1.472, p < .001), age > 50 years (OR: 1.340, p < .001), previous use of macrolide antibiotics (clarithromycin, OR: 2.902, p < .001; azithromycin, OR: 1.930, p < .001; erythromycin, OR: 2.060, p = .001; roxithromycin, OR: 2.022, p < .001), and history of respiratory comorbidity (sinusitis, OR: 1.271, p < .001; laryngopharyngitis, OR: 1.135, p = .032; bronchitis, OR: 1.245, p = .001; pneumonia, OR: 1.335, p = .026) were independent risk factors of clarithromycin resistance in H. pylori.
Conclusions
The use of macrolide antibiotics and a recent diagnosis of respiratory disease might increase clarithromycin resistance of H. pylori.
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