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1.
Epilepsy Behav ; 155: 109786, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38653175

ABSTRACT

BACKGROUND: Although there are models predicting epilepsy recurrence under different clinical conditions, few studies have examined blood biomarkers. Inflammation plays a crucial role in the occurrence and development of epilepsy. We analyzed inflammatory mediators in a regional hospital-based epilepsy cohort and investigated their relationship with subsequent epilepsy recurrence. METHODS: Interictal inflammatory mediators were measured in 128 patients diagnosed with epilepsy participating in a prospective study. Inflammatory mediators were compared during the follow-up period between patients who experienced epilepsy recurrence and those who did not. We also assessed the correlation between inflammatory mediators and the time interval until the next recurrence. RESULTS: Over a median 4-month follow-up period, 41 patients experienced seizure recurrence. Differences in interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) levels were observed between seizure recurrence and non-recurrence groups. After adjusting for covariates through multivariate Cox regression analysis, the patients in the third IL-6 tertile (>2.31 pg/mL; HR: 2.49; 95 % CI: 1.00-6.16; P = 0.049) and in the third TNF-α tertile (>0.74 pg/mL; HR: 2.80; 95 % CI: 1.13-6.92; P = 0.026) had higher risk of seizure recurrence. The time until the next recurrence was negatively correlated with IL-6 level (ρ =  - 0.392, P = 0.011). CONCLUSION: High levels of IL-6 and TNF-α are associated with a higher possibility of seizure recurrence. Future predictive models should also include inflammatory mediators in addition to clinical variables.


Subject(s)
Epilepsy , Interleukin-6 , Recurrence , Seizures , Tumor Necrosis Factor-alpha , Humans , Female , Male , Interleukin-6/blood , Adult , Tumor Necrosis Factor-alpha/blood , Epilepsy/blood , Middle Aged , Seizures/blood , Young Adult , Prospective Studies , Follow-Up Studies , Biomarkers/blood
2.
J Environ Manage ; 368: 122219, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39153322

ABSTRACT

This study, aimed at exploring low-maintenance, high-diversity, and sustainable greening strategies for residential areas, conducted a comprehensive survey and analysis of spontaneous plants in residential green spaces in Fuzhou City, documenting 361 species. Employing methods such as variance partitioning, Canonical Correspondence Analysis (CCA), and ecological niche analysis, we investigated the environmental factors influencing the distribution and composition of these plants, as well as their interrelationships. The study found that the composition of spontaneous plants in residential green spaces differs from other urban environments, with a high proportion of alien species (43.77%) due to influences such as resident activities, including a large number of ornamental and edible plants. Maintenance level, urbanization gradient, and green space ratio are common factors affecting the composition and distribution of spontaneous plants in urban environments, while unique residential socio-economic factors like building age, housing prices, and population density significantly affect the spontaneous plants in residential green spaces. The overall dominant plant community shows a significant positive association, indicating a relatively stable stage of succession. Although competition among most species is not significant and interspecific connectivity is weak, the presence of seven dominant invasive species intensifies competition. Based on these findings, the study proposes several specific sustainable management measures: adopting the concept of New Naturalistic Ecological Planting Design, selecting native spontaneous plants with strong adaptability, and constructing plant communities that are ecologically stable and have ornamental value by mimicking natural ecosystems. Additionally, specific methods for managing specific invasive species in residential green spaces using competitive replacement control methods are proposed. These measures aim to promote the health and sustainable development of urban residential green spaces.


Subject(s)
Ecosystem , Sustainable Development , China , Conservation of Natural Resources/methods , Plants , Urbanization , Cities , Biodiversity , Introduced Species
3.
Angew Chem Int Ed Engl ; 63(13): e202314876, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38305641

ABSTRACT

The carbonate electrolyte chemistry is a primary determinant for the development of high-voltage lithium metal batteries (LMBs). Unfortunately, their implementation is greatly plagued by sluggish electrode interfacial dynamics and insufficient electrolyte thermodynamic stability. Herein, lithium trifluoroacetate-lithium nitrate (LiTFA-LiNO3 ) dual-salt additive-reinforced carbonate electrolyte (LTFAN) is proposed for stabilizing high-voltage LMBs. We reveal that 1) the in situ generated inorganic-rich electrode-electrolyte interphase (EEI) enables rapid interfacial dynamics, 2) TFA- preferentially interacts with moisture over PF6 - to strengthen the moisture tolerance of designed electrolyte, and 3) NO3 - is found to be noticeably enriched at the cathode interface on charging, thus constructing Li+ -enriched, solvent-coordinated, thermodynamically favorable electric double layer (EDL). The superior moisture tolerance of LTFAN and the thermodynamically stable EDL constructed at cathode interface play a decisive role in upgrading the compatibility of carbonate electrolyte with high-voltage cathode. The LMBs with LTFAN realize 4.3 V-NCM523/4.4 V-NCM622 superior cycling reversibility and excellent rate capability, which is the leading level of documented records for carbonate electrode.

4.
Angew Chem Int Ed Engl ; 63(22): e202403668, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38462892

ABSTRACT

The electrolyte chemistry is crucially important for promoting the practical application of lithium metal batteries (LMBs). Here, we demonstrate for the first time that 1,3-dimethylimidazolium dimethyl phosphate (DIDP) and trimethylsilyl trifluoroacetate (TMSF) can undergo in situ transesterification in carbonate electrolyte to generate dimethyl trimethylsilyl phosphate (DTMSP) and 1,3-dimethylimidazolium trifluoroacetate (DITFA) as multifunctional additives for LMBs. H2O and HF can be removed by the Si-O group in DTMSP to improve the moisture resistance of electrolyte and the stability of cathode. Furthermore, the dissolution of lithium nitrate (LiNO3) in carbonate electrolyte can be promoted by the trifluoroacetate anion (TFA-) in DITFA, thereby optimizing the solvation structure and transport kinetics of Li+. More importantly, both DTMSP and DITFA tend to preferential redox decomposition due to the low lowest unoccupied molecular orbital (LUMO) and high highest occupied molecular orbital (HOMO). Consequently, a thin and robust layer rich in P/N/Si on the cathode and an inorganic-rich layer (e.g. Li3N/Li3P) on the anode can be constructed and superior electrochemical performances are achieved. This artificial transesterification strategy to introduce favorable additives paves an efficient and ingenious route to high-performance electrolyte for LMBs.

5.
Epilepsy Behav ; 144: 109256, 2023 07.
Article in English | MEDLINE | ID: mdl-37244219

ABSTRACT

Seizure control in women with epilepsy (WWE) during pregnancy is a vital concern. The aim of this study was to compare changes in seizure frequency and anti-seizure medication (ASM ) therapy in WWE in a real-world setting over three epochs (prepregnancy, pregnancy, and postpregnancy). We screened WWE who were pregnant between 1 January 2010 and 31 December 2020 from the epilepsy follow-up registry database of a tertiary hospital in China. We reviewed and collected follow-up data for the following time periods: 12 months before pregnancy (epoch 1), throughout pregnancy and the first 6 weeks postpartum (epoch 2), and from 6 weeks to 12 months postpartum (epoch 3). Seizures were classified into two categories: tonic‒clonic/focal to bilateral tonic‒clonic seizures and non-tonic‒clonic seizures. The main indicator was the seizure-free rate over the three epochs. Using epoch 1 as a reference, we also compared the percentage of women with an increased seizure frequency, as well as changes in ASM treatment, in epochs 2 and 3. Ultimately, 271 eligible pregnancies in 249 women were included. The seizure-free rates in epoch 1, epoch 2, and epoch 3 were 38.4%, 34.7%, and 43.9%, respectively (P = 0.09). The top three ASMs used in the three epochs were lamotrigine, levetiracetam, and oxcarbazepine. Using epoch 1 as a reference, the percentages of women with increased frequencies of tonic‒clonic/focal to bilateral tonic‒clonic seizures in epoch 2 and epoch 3 were 17.0% and 14.8%, respectively, while the percentages of women with an increased frequency of non-tonic‒clonic seizures in epoch 2 and epoch 3 were 31.0% and 21.8% (P = 0.02). The percentage of women whose ASM dosages were increased in epoch 2 was higher than that in epoch 3 (35.8% vs. 27.3%, P = 0.03). The seizure frequency during pregnancy may not differ significantly from that during prepregnancy and postpregnancy if WWE are treated according to the guidelines.


Subject(s)
Epilepsy , Pregnancy Complications , Pregnancy , Female , Humans , Pregnancy Complications/drug therapy , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Lamotrigine/therapeutic use , Seizures/drug therapy
6.
Front Pharmacol ; 15: 1369384, 2024.
Article in English | MEDLINE | ID: mdl-38560357

ABSTRACT

Objective: This study aims to analyze adverse drug events (ADEs) associated with cenobamate from the FAERS database, covering the third quarter of 2020 to the second quarter of 2023. Methods: Data related to cenobamate-associated ADEs from the third quarter of 2020 to the second quarter of 2023 were collected. After standardizing the data, various signal quantification techniques, including ROR, MHRA, BCPNN, and MGPS, were employed for analysis. Results: Among 2535 ADE reports where cenobamate was the primary suspected drug, 94 adverse reactions involving 11 different System Organ Class (SOC) categories were identified through the application of four signal quantification techniques. More specifically, neurological disorders and injuries resultant from complications are frequent adverse reactions associated with cenobamate. Conclusion: Our research findings align with established results, affirming the favorable safety profile of cenobamate. Effective prevention of adverse reactions induced by cenobamate can be achieved through the establishment of efficient blood concentration monitoring and dose adjustments.

7.
Front Neurol ; 15: 1386408, 2024.
Article in English | MEDLINE | ID: mdl-38988599

ABSTRACT

Purpose: The purpose of study was to describe the association between ferritin and all-cause mortality of cases with stroke. Methods: Clinical data derived from Multiparameter Intelligent Monitoring in Intensive Care were analyzed. The primary endpoint was 30-day mortality. The potential prognostic roles of Ferritin L were analyzed by Cox proportional hazard models. The independent prognostic roles of Ferritin L in the cases were analyzed by smooth curve fitting. Results: Concerning 30-day mortality, the HR (95% CI) for a high Ferritin (≥373) was 1.925 (1.298, 2.854; p = 0.00113), compared to a low ferritin (< 373). After adjusting for multiple confounders, the HR (95% CI) for a high Ferritin (≥373) was 1.782 (1.126, 2.820; p = 0.01367), compared to a low Ferritin (< 373). A non-linear association between Ferritin and 30-day mortality was found. Using recursive algorithm and two-piecewise linear regression model, inflection point (IP) was calculated, which was 2,204. On the left side of the IP, there was a positive relationship between Ferritin and 30-day mortality, and the effect size, 95% CI and p value were 1.0006 (1.0004, 1.0009) p < 0.0001, respectively. On the right of the IP, the effect size, 95% CI and p value were 1.0000 (1.0000, 1.0000) and 0.3107, respectively. Conclusion: Ferritin was associated with increased risk of stroke; it is important to further examine the association if the increased uric acid would increase the outcome of stroke in a longitudinal study. The non-linear relationship between Ferritin and all-cause mortality of stroke was observed. Ferritin was a risk factor for the outcome of stroke when ferritin was <2204.

8.
Sci Bull (Beijing) ; 69(11): 1686-1696, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38423878

ABSTRACT

Rational carbonate electrolyte chemistry is critical for the development of high-voltage lithium metal batteries (LMBs). However, the implementation of traditional carbonate electrolyte is greatly hindered by the generation of an unstable electrode interphase and corrosive by-product (HF). Herein, we propose a triple-function eutectic solvent additive of N-methylacetamide (NmAc) with LiNO3 to enhance the stability and compatibility of carbonate electrolyte. Firstly, the addition of NmAc significantly improves the solubility of LiNO3 in carbonate electrolyte by forming an eutectic pair, which regulates the Li+ solvation structure and leads to dense and homogenous Li plating. Secondly, the hydrolysis of acidic PF5 is effectively alleviated due to the strong complexation of NmAc with PF5, thus reducing the generation of corrosive HF. In addition, the optimized cathode electrolyte interphase layer decreases the structural degradation and transition metal dissolution. Consequently, Li||LiNi0.6Co0.2Mn0.2O2 (NCM622) cells with the designed electrolyte deliver superior long-term cycle reversibility and excellent rate capability. This study unveils the rationale for incorporating eutectic solvent additives within carbonate electrolytes, which significantly contribute to the advancement of their practical application for high-voltage LMBs.

9.
Article in English | MEDLINE | ID: mdl-38280164

ABSTRACT

The treetop walk is an innovative urban greenway that harmoniously integrates with the natural topography, meandering through the tree canopy. It serves as a vital element in elevating the urban mountain landscape while also significantly impacting the recreational experiences of the public through its microclimate effects. Moreover, the distinctive plant community characteristics of the treetop walk significantly enhance the microclimate. Examining the plant community attributes that potentially influence the microclimate conditions of the treetop walk is of utmost importance. We chose the Fu Forest Trail in Fuzhou as the sample site for this research. By implementing an orthogonal experimental design and using ENVI-met software, we simulated data to explore the impacts of various plant community characteristics on the microclimate of the treetop walk in autumn. The findings revealed the following results: (1) The presence of tree height, leaf area index, crown type, and planting density significantly influenced the microclimate of the treetop walk green spaces, with some factors having primary effects while others having secondary effects. (2) No significant variations were observed in the microclimate effects of diverse plant community characteristics in the treetop walk during morning, noon, and evening hours. (3) Scheme 13 emerged as the optimal choice for cooling and humidifying ventilating, characterized by a tree height of 20 m, leaf area index of 4.4, spherical crown shape, and planting spacing of 2 m. The tree species available in the Fuzhou area include Ligustrum quihoui Carr., Buxus sinica, Laurus nobilis, Myrica rubra, and Osmanthus fragrans. (4) Compared to traditional understory trails, tree height and planting spacing notably influence the microclimate environment of the treetop walk.

10.
Article in English | MEDLINE | ID: mdl-38347362

ABSTRACT

Ecosystems depend on biodiversity; therefore, protecting biodiversity is beneficial for the development of ecosystems. Butterflies are indicator species that respond quickly to environmental changes and reflect environmental conditions. Butterfly diversity is a crucial evaluation indicator of habitat quality in green spaces. We used CiteSpace and Bibliometrix to conduct a bibliometric analysis of research relating to butterfly diversity in green spaces. Based on 538 papers published from 2002-2022, we systematically reviewed the status, frontiers, and hotspots for research on butterfly diversity in green spaces. Our results showed that: (1) Research on butterfly diversity in green spaces has consistently demonstrated an upward trend between 2002-2022. Studies on this subject have garnered attention from researchers worldwide, with notable interest and contributions from scholars in the United States. (2) Early studies focused on butterfly habitat preferences and extinction concerns, and later articles appeared on the influence of external environmental factors (land use, climate change, plants, etc.). (3) Three main research topics received much attention between 2002 and 2022: biodiversity conservation, butterfly habitats, and the relationship between butterfly diversity and its influencing factors. (4) The relationship between green spaces and butterfly diversity (landscape features, vegetation features, and human activities) was discussed; these factors on butterfly communities should be considered in the planning and constructing of future green spaces. (5) Two significant future directions have been identified: more research on the impact of external factors and a need for more technical integration with the big data field. Future research on butterfly diversity in green spaces should adopt a more multi-scale, multi-disciplinary approach and aim to enhance the practicality and guidance of research findings.

11.
ACS Appl Mater Interfaces ; 15(29): 34852-34861, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37459587

ABSTRACT

The high specific capacity and relatively low volume expansion of silicon suboxide (SiOx) highlight its potential as one of the most promising anode materials for lithium-ion batteries. Nevertheless, the traditional binder of polyacrylic acid (PAA) still cannot adapt to enormous stress during the repeated volume expansion/contraction owing to its intrinsic rigid backbone. Inspired by the "soft and hard composite body armor", we herein design a double-wrapped binder consisting of PAA with a high internal Young's modulus (hard part) and polyurethane (DOU) with a low external Young's modulus (soft part). When the SiOx particle expands during lithiation, the rigid PAA firstly accommodates the volume change to dissipate most of the inner stress, and the elastic DOU with triple dynamic bonds serves as a buffer layer to absorb the residual stress via the breakage/formation of dynamic bonds. By optimizing the PAA/DOU ratio, the SiOx anode can maintain the integrity during long-term cycling and deliver a relatively high reversible capacity of 1064.1 mAh g-1 with a preeminent capacity retention of 83.7% at 0.5C after 300 cycles. Such a double-wrapped binder can provide a novel design strategy for multicomponent functional polymer binders toward high-performance SiOx anodes.

12.
Animals (Basel) ; 13(11)2023 May 26.
Article in English | MEDLINE | ID: mdl-37889726

ABSTRACT

Butterflies are key indicators of urban biodiversity and one of the most vulnerable organism groups to environmental changes. Studying how butterflies are distributed and what factors might influence them in urban green spaces is crucial. In this study, from July 2022 to September 2022, we examined and analyzed the butterfly diversity in nine parks in Fuzhou, China, along three different levels of urbanization (urban, peri-urban, and suburban). We investigated how butterfly communities respond to increasing urbanization. The findings revealed that: (1) A total of 427 butterfly individuals from 4 families and 13 species were observed; (2) Shannon diversity, richness, and abundance of the overall butterfly community were lower in the more urbanized parks. Urbanization had significant effects on Shannon diversity (p = 0.003) and abundance (p = 0.007) but no significant effects on the whole butterfly community richness (p = 0.241); (3) non-metric multidimensional scaling revealed that there were differences in the overall number of butterfly species in urban parks among different geographic regions.

13.
Insects ; 14(11)2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37999049

ABSTRACT

Urbanization has been shown to cause biodiversity loss. However, its effects on butterfly taxonomic and functional diversity still need to be studied, especially in urban waterfront green spaces where mechanisms of impact still need to be explored. We used butterflies as indicators to study how urbanization affects their taxonomic and functional diversity and identify indicator species in different urban ecological gradient areas. From July to September 2022, we surveyed 10 urban waterfront green spaces in Fuzhou City, China. We recorded 1163 butterflies of 28 species from 6 families. First, we explored the effects of urbanization on butterfly communities and made pairwise comparisons of different urban ecological gradients (α-diversity); secondly, we looked for differences between butterfly communities across urban ecological gradients (ß-diversity); finally, we investigated differences in the response of butterfly functional groups to different urban ecological gradient areas and identified ecological indicative species. This study found the following: (1) Urbanization has led to the simplification of butterfly community structure, but there are also favorable factors that support the survival of individual butterflies; (2) Urbanization has led to significant differences in butterfly communities and plant-feeding polyphagous butterfly groups; (3) Urbanization has led to differences in the functional diversity of butterfly diet and activity space groups; (4) We identified five eco-indicator species in different urban ecological gradients.

14.
Anal Methods ; 14(46): 4893-4902, 2022 12 01.
Article in English | MEDLINE | ID: mdl-36420616

ABSTRACT

In order to effectively remove grease for the detection of sulfonamides, a non-toxic and low-cost hierarchical porous zirconia material was synthesized using the dual template method. The lipid impurities in an animal-derived food matrix can be absorbed by hierarchical zirconia. A ZrO2 prepolymer was synthesized by mixing amphiphilic triblock copolymer poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123) with tannin extract as the double template and Zr(SO4)2 as the metal source. After aging, drying and calcination at high temperature, the prepolymer transforms into a hierarchical porous structure. The synthesized materials were characterized using SEM, XRD, FT-IR, and BET. The results show that the material has an abundant pore structure and hierarchical pore structure. The adsorption conditions were optimized. The hierarchical porous ZrO2 synthesized by this method is relatively uniform, and is characterized by large specific surface area as well as high lipid impurity adsorption capacity. Through the optimization experiment of adsorption conditions, we found that hierarchical porous ZrO2 can reach the maximum adsorption capacity in 60 min under weak acidic conditions. The samples are used for actual sample testing such as HPLC of sulfadiazine (SD), sulfamethazine (SM2), sulfamethoxydiazine (SMD), sulfamethoxazole (SIZ) and sulfadimethoxine (SDM), and the recovery experiment of sulfonamides in chicken was carried out. The recoveries were 80.9-97.6% and the detection limit was 3.8-17.6 µg L-1. This work provides a new strategy for oil removal using hierarchical porous materials.


Subject(s)
Polyethylene Glycols , Sulfonamides , Animals , Porosity , Spectroscopy, Fourier Transform Infrared , Sulfanilamide , Lipids
15.
Vaccines (Basel) ; 10(10)2022 Sep 23.
Article in English | MEDLINE | ID: mdl-36298469

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has imposed enormous morbidity and mortality burdens. Patients with rheumatic diseases (RDs) are vulnerable to the COVID-19 infection, given their immunocompromised status. Ensuring acceptance of the COVID-19 vaccine is important and has attracted attention by health professionals. In this study, we designed an online cross-sectional survey that used an online questionnaire from 8 May 2021 to 4 October 2021. Attitudes toward the COVID-19 vaccination, personal information, current disease activity status, adverse events (AEs), and knowledge sources of vaccines were collected. Descriptive statistics, nonparametric tests, and ordinal logistic regression were used to analyze the data. A total of 1022 questionnaires were received, among which 70.2% (720/1022) of patients with RDs agreed to vaccination, while only 31.6% of patients were actually vaccinated. Male, employed, high-income patients and those with inactive disease showed a more positive attitude. Concerns of AEs and disease flare were the main factors affecting vaccination willingness. Only 29.6% (304/1022) of patients thought they had received enough information about the COVID-19 vaccine from their doctors. In conclusion, most patients with RDs in China intended to get vaccinated, although the vaccination rate in this particular population was low. Rheumatologists should take more responsibility in COVID-19 vaccination education of patients with RDs.

16.
J Mech Behav Biomed Mater ; 124: 104787, 2021 12.
Article in English | MEDLINE | ID: mdl-34534844

ABSTRACT

Stiff biological materials (SBMs), such as nacre and bone, are composites that display remarkable toughness enhancements over their primary constituents, which are brittle minerals. These enhancements are thought to be a consequence of different mechanisms made possible by the SBMs' internal lamellar architecture. One such mechanism is the Cook-Gordon (crack-arrest-and-reinitiation) mechanism, whose operation manifests in flexural tests as a sawtooth pattern in the force-displacement curves. The curves from flexural tests carried out on marine sponge spicules, which also possess a lamellar architecture, also display a sawtooth-pattern, suggesting the presence of the Cook-Gordon mechanism. Intriguingly, the spicules were recently found not to display any significant toughness enhancement. To resolve this apparent contradiction, in the preceding paper (Kochiyama et al., 2021), we put forward the hypothesis that the sawtooth pattern was due to the spicules slipping at the tests' supports. In this paper, we present a model for the spicule's flexural tests in which we allow for the possibility for the specimen to slip at the test's supports. We model contact between the specimen and the test's supports using the Coulomb's friction law. By choosing experimentally reasonable values for the friction coefficient, we were able to get the model's predictions to match experimental measurements remarkably well. Additionally, on incorporating the spicules' surface roughness into the model, which we did by varying the friction coefficient along the spicule's length, its predictions can also be made to match the measured sawtooth patterns. We find that the sawtooth patterns in the model are due to slip type instabilities, which further reinforces the hypothesis put forward in our preceding paper.


Subject(s)
Nacre , Porifera , Animals , Bone and Bones , Friction , Mechanical Phenomena
17.
J Mech Behav Biomed Mater ; 119: 104362, 2021 07.
Article in English | MEDLINE | ID: mdl-33901967

ABSTRACT

Layered architectures are prevalent in tough biological composites, such as nacre and bone. Another example of a biological composite with layered architecture is the skeletal elements-called spicules-from the sponge Euplectella aspergillum. Based on the similarities between the architectures, it has been speculated that the spicules are also tough. Such speculation is in part supported by a sequence of sudden force drops (sawtooth patterns) that are observed in the spicules' force-displacement curves from flexural tests, which are thought to reflect the operation of fracture toughness enhancing mechanisms. In this study, we performed three-point bending tests on the spicules, which also yielded the aforementioned sawtooth patterns. However, based on the analysis of the micrographs obtained during the tests, we found that the sawtooth patterns were in fact a consequence of slip events in the flexural tests. This is put into perspective by our recent study, in which we showed that the spicules' layered architecture contributes minimally to their toughness, and that the toughness enhancement in them is meager in comparison to what is observed in bone and nacre [Monn MA, Vijaykumar K, Kochiyama S, Kesari H (2020): Nat Commun 11:373]. Our past and current results underline the importance of inferring a material's fracture toughness through direct measurements, rather than relying on visual similarities in architectures or force-displacement curve patterns. Our results also suggest that since the spicules do not possess remarkable toughness, re-examining the mechanical function of the spicule's intricate architecture could lead to the discovery of new engineering design principles.


Subject(s)
Mechanical Phenomena , Nacre , Bone and Bones , Materials Testing
18.
Biomaterials ; 270: 120684, 2021 03.
Article in English | MEDLINE | ID: mdl-33535143

ABSTRACT

Mechanical forces are an essential element to early tissue formation. However, few techniques exist that can quantify the mechanical microenvironment present within cell-dense neotissues and organoid structures. Here is a versatile approach to measure microscale, cellular forces during mesenchymal condensation using specially tailored, hyper-compliant microparticles (HCMPs). Through monitoring of HCMP deformation over both space and time, measurements of the mechanical forces that cells exert, and have exerted on them, during tissue formation are acquired. The current study uses this technology to track changes in the mechanical microenvironment as mesenchymal stem cells self-assemble into spheroids and condense into cohesive units. An array analysis approach, using a high-content imaging system, shows that cells exert a wide range of tensile and compressive forces during the first few hours of self-assembly, followed by a period of relative equilibrium. Cellular interactions with HCMPs are further examined by applying collagen coating, which allows for increased tensile forces to be exerted compared to non-coated HCMPs. Importantly, the hyper-compliant nature of our force sensors allows for increased precision over less compliant versions of the same particle. This sensitivity resolves small changes in the microenvironment even at the earliest stages of development and morphogenesis. The overall experimental platform provides a versatile means for measuring direct and indirect spatiotemporal forces in cell-dense biological systems.


Subject(s)
Cell Communication , Mechanical Phenomena , Collagen , Morphogenesis
19.
Eur Radiol ; 20(4): 978-83, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19789876

ABSTRACT

OBJECTIVE: To prospectively evaluate the feasibility of diffusion-weighted (DW) magnetic resonance (MR) imaging in the assessment of renal function in patients with chronic kidney disease (CKD). METHODS: Seventy-two healthy volunteers and 43 patients underwent coronal echo-planar DW MR imaging of the kidneys with a single breath-hold time of 16 s. The patients were grouped according to five stages as indicated by the K/DOQI CKD (kidney disease outcome quality initiative). The apparent diffusion coefficient (ADC) value of the kidneys was calculated with high b values (b = 500 s/mm(2)). The ADC values were compared between patients and healthy volunteers, and among different stages. For statistical analysis, Student's t tests, ANOVA, Pearson's correlation tests, and Spearman's correlation tests were used. RESULTS: No difference between the cortex and medulla could be observed on DW images of all volunteers. Patients with CKD had significantly lower renal ADC (t = -4.383, P = 0.000) than volunteers. The ADC values of kidneys were significantly lower than normal at most stages of CKD, except CKD1. There was a negative correlation between the ADCs and serum creatinine (sCr) level (P = 0.000) amongst the patients. CONCLUSION: Diffusion-weighted MR imaging is feasible in the assessment of renal function, especially in the detection of early stage renal failure of CKD.


Subject(s)
Algorithms , Diffusion Magnetic Resonance Imaging/methods , Image Interpretation, Computer-Assisted/methods , Kidney Failure, Chronic/diagnosis , Kidney/pathology , Adult , Aged , Female , Humans , Image Enhancement/methods , Male , Middle Aged , Pilot Projects , Reproducibility of Results , Sensitivity and Specificity , Young Adult
20.
Thyroid ; 30(9): 1236-1244, 2020 09.
Article in English | MEDLINE | ID: mdl-32212919

ABSTRACT

Background: Diagnosis of thyrotropin (TSH)-secreting pituitary adenomas (TSHoma) before surgery remains a challenge, especially for microadenomas. We aimed to establish a short-term somatostatin analogue (SSA) test to differentiate TSHomas from other causes of syndromes of inappropriate secretion of TSH (IST), mainly resistance to thyroid hormone ß (RTHß). Materials and Methods: We first evaluated the sensitivity and specificity of SSA test in a training cohort (TSHoma, n = 32; RTHß, n = 20). The test was then validated in an independent cohort (TSHoma, n = 9; RTHß, n = 2). We finally applied the SSA test in 12 perceptively enrolled IST cases with negative imaging findings and absent thyroid hormone receptor beta (THRB) mutations or mixed hormone imbalances. Results: Both TSHoma and RTHß patients showed a decrease of TSH at the start of the SSA test, but the velocity of the TSH suppression slowly decreased in RTHß patients after 2 hours. The suppression ratio of TSH at 24 hours versus 2 and 0 hours was significantly greater in TSHoma patients compared with RTHß patients (70.58% ± 18.6% vs. 6.01% ± 25.41%, p < 0.0001, 79.83% ± 12.79% vs. 51.16% ± 13.62%, p < 0.0001, respectively). The 24- versus 2-hour suppression ratio showed the best diagnostic accuracy at a cut point of 44.46% in the training cohort, with a sensitivity of 95.00%, a specificity of 93.75%, and a positive predictive value (PPV) of 88.89%. The accuracy was confirmed in the validation cohort. Three out of 12 patients in the prospective cohort showed a TSH suppression ratio greater than 44.46% and all developed microadenomas during follow-up. Conclusions: A short-term SSA test provides an alternative diagnostic approach for TSHomas. A positive SSA test result is suggestive for a TSHoma even before positive findings become apparent on pituitary imaging. However, studies including larger number of patients, especially those with RTHß, are needed to confirm our findings.


Subject(s)
Adenoma/diagnosis , Adenoma/metabolism , Pituitary Neoplasms/diagnosis , Pituitary Neoplasms/metabolism , Somatostatin/analogs & derivatives , Thyrotropin/metabolism , Adolescent , Adult , Aged , Area Under Curve , Cell Differentiation , Child , Child, Preschool , DNA Mutational Analysis , Female , Humans , Male , Middle Aged , Pituitary Gland/metabolism , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Thyroid Hormone Resistance Syndrome/diagnosis , Young Adult
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