Mitochondria fission accentuates oxidative stress in hyperglycemia-induced H9c2 cardiomyoblasts in vitro by regulating fatty acid oxidation.

Oxidative stress plays a pivotal role in the development of diabetic cardiomyopathy (DCM). Previous studies have revealed that inhibition of mitochondrial fission suppressed oxidative stress and alleviated mitochondrial dysfunction and cardiac dysfunction in diabetic mice. However, no research has confirmed whether mitochondria fission accentuates hyperglycemia-induced cardiomyoblast oxidative stress through regulating fatty acid oxidation (FAO). We used H9c2 cardiomyoblasts exposed to high glucose (HG) 33 mM to simulate DCM in vitro. Excessive mitochondrial fission, poor cell viability, and lipid accumulation were observed in hyperglycemia-induced H9c2 cardiomyoblasts. Also, the cells were led to oxidative stress injury, lower adenosine triphosphate (ATP) levels, and apoptosis. Dynamin-related protein 1 (Drp1) short interfering RNA (siRNA) decreased targeted marker expression, inhibited mitochondrial fragmentation and lipid accumulation, suppressed oxidative stress, reduced cardiomyoblast apoptosis, and improved cell viability and ATP levels in HG-exposed H9c2 cardiomyoblasts, but not in carnitine palmitoyltransferase 1 (CPT1) inhibitor etomoxir treatment cells. We also found subcellular localization of CPT1 on the mitochondrial membrane, FAO, and levels of nicotinamide adenine dinucleotide phosphate (NADPH) were suppressed after exposure to HG treatment, whereas Drp1 siRNA normalized mitochondrial CPT1, FAO, and NADPH. However, the blockade of FAO with etomoxir abolished the above effects of Drp1 siRNA in hyperglycemia-induced H9c2 cardiomyoblasts. The preservation of mitochondrial function through the Drp1/CPT1/FAO pathway is the potential mechanism of inhibited mitochondria fission in attenuating oxidative stress injury of hyperglycemia-induced H9c2 cardiomyoblasts.

Unraveling the Atomic Shuffles of Twinning Nucleation in Hexagonal Close-Packed Rhenium Nanocrystals.

Reining in deformation twinning is crucial for the mechanical properties of hexagonal close-packed (HCP) metals and hinges on an explicit understanding of the twinning nucleation mechanism. Unfortunately, it is often suggested rather than conclusively demonstrated that twinning nucleation can be mediated by pure atomic shuffles. Herein, by utilizing in situ high-resolution transmission electron microscopy, we have dissected the atomic shuffling mechanism during the {101̅2} twinning nucleation in rhenium nanocrystals, which revealed the emergence of an intermediate body-centered tetragonal (BCT) structure. Specifically, the double-layered prismatic planes initially shuffle into single-layered {11̅0}BCT planes; subsequently, adjacent {22̅0}BCT planes shuffle in opposite directions to form the basal planes of the twin embryo. This shuffling mechanism is further corroborated by molecular dynamic simulations. The finding provides direct evidence of shuffle-dominated twinning nucleation with atomic details that may lead to better control of this critical twinning mode in HCP metals.

Superhydrophobicity Mechanism and Nanoscale Profiling of PDMS-Modified Kaolinite Nanolayers via Ab Initio-MD Simulation and Atomic Force Microscopy Study.

This study aimed to investigate the superhydrophobic mechanism of kaolinite particles modified with poly(dimethylsiloxane) (PDMS), which has potential as a superior hydrophobic coating. The study employed a combination of density functional theory (DFT) simulation modeling, characterization of the chemical properties and microstructure, contact angle measurements, and chemical force spectroscopy of atomic force microscopy. The results showed successful PDMS grafting onto the kaolinite surface, resulting in micro- and nanoscale roughness and a contact angle of 165°, indicating a successful superhydrophobic effect. The study also identified the mechanism of the hydrophobic interaction through two-dimensional micro- and nanoscale hydrophobicity images, highlighting the potential of this approach for developing new hydrophobic coatings.

Steerable artificial magnetic bacteria with target delivery ability of calcium carbonate for soil improvement.

The microbial-induced carbonate precipitation (MICP) has acquired significant attention due to its immense potential in sustainable engineering applications, particularly in soil improvement. However, the precise control of microbial-induced calcium carbonate precipitation remains a formidable challenge in engineering practices, owing to the uncertain movement paths of bacteria and the nonuniform distribution of soil pores. Taking inspiration from targeted therapy in medicine, this paper presents novel research on the development and validation of magnetically responsive bacteria. These bacteria demonstrate the ability to target calcium carbonate precipitation in a microfluidic chip, thereby promoting an environmentally friendly and ecologically sustainable biomineralization paradigm. The study focuses on investigating the migration of magnetite nanoparticles (MNPs) in aqueous solutions and enhancing the stability of MNP culture liquids. A specially designed microfluidic chip is utilized to simulate natural sand particles and their pores, while an external magnetic field is applied to precisely control the movement path of the artificial magnetic bacteria, enabling targeted precipitation of calcium carbonate at the micron-scale. Verification of the engineered artificial magnetic bacteria and their ability to induce calcium carbonate precipitation is conducted through SEM-EDS analysis, microfluidic chip observations, and the application of the K-means algorithm and ImageJ software to analyze calcium carbonate formation. The influence of the concentration of magnetic nanoparticles on the calcium carbonate production rate was also studied. The results confirm the potential of the artificial magnetic bacteria for future engineering applications. KEY POINTS: • Sporosarcina pasteurii is first time successfully engineered into artificial magnetic bacteria. • The artificial magnetic bacteria show excellent performance of targeted transportation and directional deposition of CaCO3 in microfluidic chip. • The emergence of artificial magnetic bacteria promotes paradigm shift of next generation environmentally friendly biomineralization.

Zavarzinia marina sp. nov., a novel hydrocarbon-degrading bacterium isolated from deep chlorophyll maximum layer seawater of the West Pacific Ocean and emended description of the genus Zavarzinia.

A Gram-stain-negative, motile, non-spore-forming, strictly aerobic and rod-shaped bacterial strain, Adcm-6AT, was isolated from a seawater sample collected from the deep chlorophyll maximum layer in the West Pacific Ocean. Strain Adcm-6AT grew at 20-37 °C (optimum, 28-32 °C), at pH 6-11 (pH 7) and in the presence of 0-6 % (1-2 %) NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that it belonged to the genus Zavarzinia and had 97.7 and 96.9 % sequence similarity to Zavarzinia compransoris DSM 1231T and Zavarzinia aquatilis JCM 32263T, respectively. Digital DNA-DNA hybridization and average nucleotide identity values between strain Adcm-6AT and the two type strains were 22.2-22.9 % and 79.7-80.4 %, respectively. The principal fatty acids were C19:0 cyclo ω8c, summed feature 8 (C18:1 ω6c and/or C18:1 ω7c) and C16:0. The predominant respiratory quinone was Q-10. The polar lipids were diphosphatidylglycerol, two phosphatidylethanolamines, two phosphatidyglycerols and an unidentified lipid. The genomic DNA G+C content of strain Adcm-6AT was 67.7 %. Based on phylogenetic analysis and genomic-based relatedness indices, as well as phenotypic and genotypic characteristics, strain Adcm-6AT represents a novel species within the genus Zavarzinia, for which the name Zavarzinia marina sp. nov. is proposed. The type strain is Adcm-6AT (=MCCC M24951T=KCTC 82849T).

Zunongwangia pacifica sp. nov., isolated from surface seawater of the Western Pacific Ocean.

Zunongwangia is a group of marine bacteria with important industrial application potential and ecological functions. In this study, a Gram-stain-negative, rod-shaped, non-motile, strictly aerobic and bright yellow pigmented bacterial strain within this genus, designated C2-37M9T, was isolated from a surface seawater sample from the Philippine Basin in the Western Pacific Ocean. Strain C2-37M9T grew at 10-44 °C (optimum, 28-30 °C), pH 6-9 (pH 7) and in the presence of 0-12 % NaCl (w/v; 2-3 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that it belonged to the genus Zunongwangia and had 95.7-98.7 % sequence similarity to all type strains of this genus, with the highest value corresponding to Zunongwangia profunda (98.7 %). Digital DNA-DNA hybridization, average nucleotide identity and average amino acid identity values between strain C2-37M9T and all valid type strains were 27.5-32.3, 83.8-86.7 and 86.9-89.0 %, respectively. The principal fatty acids (>5 %) were iso-C15 : 0, iso-C17 : 0 3-OH, anteiso-C15 : 0, summed feature 9 (C16 : 0 10-methyl and/or iso-C17 : 1 ω9c), iso-C15 : 1 G and summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c). The predominant respiratory quinone was MK-6. The polar lipids were one phosphatidylethanolamine, two unknown glycolipids, three unidentified aminolipids and six unidentified lipids. The genomic DNA G+C content of strain C2-37M9T was 36.7 mol%. Based on phylogenetic results and genomic-based relatedness indices, as well as phenotypic and genotypic characteristics, strain C2-37M9T represents a novel species within the genus Zunongwangia, for which the name Zunongwangia pacifica sp. nov. is proposed. The type strain is C2-37M9T (=MCCC M21534T=KCTC 82852T).

Crystal transformation and self-assembly theory of microbially induced calcium carbonate precipitation.

Microbially induced calcium carbonate precipitation (MICP) is ubiquitous in the earth's lithosphere and brings the inspiration of bionic cementation technology. Over recent years, MICP has been proposed as a potential solution to address many environmental and engineering issues. However, the stability of cemented precipitations generated via MICP technology, especially the characteristics and change mechanism of crystal forms, is still unclear, which substantially hindered the understanding of biomineralization and prohibited the application and upscaling of MICP technology. Here, Sporosarcina pasteurii was selected as a model microbe to induce calcium carbonate mineralization in a series of standard nutrient solutions. The authors studied the process of precipitation from amorphous calcium carbonate to calcite crystal form and revealed the assembly behavior and mechanism of precipitations by FTIR, SEM, TEM and EDS. In the two crystal forms of induced calcium carbonate, the relative position and content of C, O, N, P and Ca elements were only slightly different. The molecular attachment and structural match of organic matrix made the crystals form change. Finally, a self-assembly theory was proposed to MICP, and it provided a solid theoretical basis for the technical specification of MICP technology in engineering application. KEY POINTS: • Organic matrix is intensively involved in MICP by forming functional groups. • Molecular attachment and structural match cause calcite crystal evolution. • A self-assembly theory is proposed for MICP.

Rigidified Cavitand Hosts in Water: Bent Guests, Shape Selectivity, and Encapsulation.

We report the synthesis and characterization of two water-soluble container compounds (cavitand hosts) with rigidified open ends. One cavitand uses four (CH2)4's as spacers to bridge the adjacent walls, while another cavitand uses four CH2CH2OCH2CH2's bridges and features a wider open end. The spacers preorganize the deep cavitands into vase-like, receptive shapes and prevent their unfolding to the unreceptive kite-like conformation. Cycloalkane guests (C6-C8) and small n-alkanes (C5-C7) form 1:1 complexes with the cavitands and move freely in the cavitands' spaces. Hydrophilic compounds 1,4-dioxane, tetrahydrofuran, tetrahydropyran, pyridine, and 1-methylimidazole also showed good binding affinity to the new cavitands. Longer alkanes (C11-C14) and n-alcohols (C11-C16) are taken up with a -CH3 group fixed at the bottom of the cavity and the groups near the rim in compressed conformations. The methylene bridges appear to divide the cavitand into a narrow hydrophobic compartment and a broader space with exposure to the aqueous medium. Longer alkane guests (C15-C18), N,N-dimethyldioctylammonium, and dioctylamine induce the formation of capsules (2:1 host:guest complexes). The new cavitands showed selectivity for p/m-cresol isomers and xylene isomers. The cavitand with CH2CH2OCH2CH2 bridges bound long-chain α,ω-diols (C13-C15) and diamines in folded, U-shaped conformations with polar functions exposed to the aqueous medium. It was used to separate o-xylene from its isomers by using simple extraction procedures.

A 5G-powered robot-assisted teleultrasound diagnostic system in an intensive care unit.

BACKGROUND: Teleultrasound provides an effective solution to problems that arise from limited medical resources, a lack of local expertise, and scenarios where the risk of infection is high. This study aims to explore the feasibility of the application of a 5G-powered robot-assisted teleultrasound diagnostic system in an intensive care unit. METHODS: In this study, the robot-assisted teleultrasound diagnostic system MGIUS-R3 was used. Using 5G network technology, the doctor manipulates the robotic arm to perform teleultrasound examination. The doctor can adjust parameters via the teleultrasound control panel, and real-time transmission of audio, video and ultrasound images can facilitate simultaneous communication between both parties. All patients underwent robot-assisted teleultrasound examination and bedside ultrasound examination of the liver, gallbladder, pancreas, spleen, kidney, as well as assessment for pleural effusion and abdominal effusion. We evaluated the feasibility of the application of the robot-assisted teleultrasound diagnosis system in the intensive care unit in terms of consultation duration, image quality, and safety. We also compared diagnostic consistency and differences. RESULTS: Apart from one patient who was excluded due to severe intestinal gas interference and poor image quality, a total of 32 patients were included in this study. Every patient completed all relevant examinations. Among them, 20 patients were male; 12 were female. The average age of the patients was 61 ± 20 years. The average duration of teleultrasound diagnosis was 17 ± 7 min. Of the 32 patients, 26 had positive results, 6 had negative results, and 5 had inconsistent diagnoses. The overall diagnostic results were basically the same, and there were no differences in diagnostic levels between the two. The overall average image quality score was 4.73 points, which represented a high-quality image. After robot-assisted teleultrasound examination, no significant changes were observed in the vital signs of patients as compared to before examination, and no examination-related complications were found. CONCLUSION: The 5G-powered robot-assisted teleultrasound diagnostic system was associated with the benefits of clear images, simple operation, relatively high levels of consistency in terms of diagnostic results, higher levels of safety, and has considerable application value in the intensive care unit.

Expression of Rho Kinase and Its Mechanism in the Left Atrial Appendage in Patients with Atrial Fibrillation.

AIM: To study the expression of Rho kinase (Rho associated coil forming protein kinase-1, ROCK-1) and its substrate myosin phosphatase target subunit 1 (myosin phosphatase target subunit-1, MYPT-1), connexin 40 (Cx40) and connexin 43 (Cx43) in the left atrial appendage of patients with atrial fibrillation, and explore the role of ROCK signaling pathway in patients with atrial fibrillation and its underlying mechanism. Methods: 40 patients undergoing open heart surgery were divided into two groups; atrial fibrillation group (AF group) and sinus rhythm group (SR group). About 100 mg of left atrial appendage tissue was taken during surgery and quickly frozen in liquid nitrogen. Immunohistochemistry and western blot were performed to evaluate the expression and location of ROCK-1, MYPT-1, Cx40 and Cx43 in the left atrial appendage tissue. Results: The results indicated that the expression of ROCK-1, MYPT-1, and Cx40 in the left atrial appendage in patients with atrial fibrillation was significantly upregulated (P < .01), the difference in the two groups was statistically significant, and ROCK-1, Cx40, and MYPT-1 expression in the AF group were higher than those in sinus rhythm group; there was a weakly positive expression of Cx43 protein in the AF group and sinus rhythm group, the difference was not statistically significant, and ROCK-1 and MYPT-1 expression showed a significant positive correlation (r = 0.968, P < .05), MYPT 1 and Cx40 protein expression was also positively correlated (r = 0.983, P < .05). Evidence in the left atrial appendage tissue of patients with atrial fibrillation showed that some proteins in Rho/ROCK pathway were upregulated, and MYPT-1 and Cx40 protein expression in AF group were significantly higher than that of SR group, which was also positively correlated; Cx43 showed a weak positive expression in both the SR group and AF group, which indicates that Rho kinase may induce expression of Cx40 by phosphorylation of MYPT-1; Cx43 may not be involved, suggesting that Rho kinase signaling pathway may activate and play an important role in the pathogenesis of atrial fibrillation lesions.

[Occupational health risk assessment of pure methanol fuel].

OBJECTIVE: To assess the occupational health risk of pure methanol fuel( M100) during the methanol fuel pilot stage. METHODS: The subjects are workers who are exposed to M100 in pilot areas for methanol vehicles, southwest of China. Use field investigation and detection to get the information of production technology, exposure level of methanol and prevention measures and facilities. Use Singapore Occupational Exposure to Harmful Chemicals Semi-Quantitative Method to assess the health risk of the methanol. Use "Classification of occupational hazards at workplace " to classify the occupational hazard of methanol. RESULTS: The main occupational hazard factor existing during the use procedure of M100 is methanol. The concentration of methanol in M100 filling station, methanol automobile repair shop and methanol automobile driver 's cab( up to47. 90 mg/m~3) and main methanol exposure post( up to 10. 25 mg/m~3) are accord with occupational exposure limit. According to the methanol occupational health riskassessment result, the risk of filling worker( R = 2. 4), methanol loade( R = 2. 0) r and maintenance worker( R = 2. 0) are low, and the risk of the driver( R = 1. 4) is negligible risk, which are basically identical with the occupational hazard classification result. CONCLUSION: Under the current production process and protection level, the occupational health risks of M100 can be controlled at low level. The chronic health effects and occupational exposure limit of methanol should be further studied.

[Risk assessment of occupational health effect of coal dust in coal wharf].

OBJECTIVE: To assess the occupational health risk of coal dust in coal wharf, identify the high risk post. METHODS: The research took workers who were exposed to coal dust in two 50- 150 thousands tons coal wharfs around bohai as subjects. The field investigation to get the infoamtion of production technology, distribution of coal dust, free silica content of coal dust, dust prevention measures and facilities, personal protection equipment, occupational health management, etc were used. The coal dust concentration of workplaces and the main positions were detected by filter membrane weighing method. The health risk of the coal dust to the main posts were assessed with the InternationalCouncil on Mining and Metals risk assessment method and occupational hazard risk index method. RESULTS: In the coal wharf, the concentration of coal dust at transferring tower, car dumper, ship loader, and coal storage yard were higher than other workplace, range of concentration: total dust 8. 8-85. 1 mg/m~3, respirable dust 2. 3- 32. 3 mg/m~3。The assessing result of ICMM method was that, 78. 6% of the posts were at "intolerable"level of occupational risk. The risk values of the driver of car dumper( 1500, 5000), the hatch commander( 1500), and the cleaners of coal storage yard( 900) were higher than transfer tower patrol workers( 600), drivers of material piling and taking machine( 450). The assessing result of occupational hazard risk index method was that, the risk degree of total dustand respirable dusttothe driver of car dumper was "severe"and "moderate"( the risk index was 40. 03 and 16. 95, respectively), and the risk degree of the total dust to the cleaners of coal unloading department and coal storage yard were "light"( the risk index was 6. 02 and 8. 70, respectively), with other posts' "no harm ". CONCLUSION: The occupational hazard of coal wharf is focused on the processes of loading and unloading( "severe"and"moderate"), transferring( "light") and reentrainment( "light").

[Effect of particle size distribution and the filtering on the free silica measurement result by pyrophosphoric acid method].

OBJECTIVE: To analyze the influence of experimental conditions: Distribution of particulate and the filter condition on the pyrophosphoric acid method for quantitative analysis of free silica in dust. METHODS: According to Method for determination of dust in the air of workplace Part 3: Distribution of particulate (GBZ/T 192.3-2007) , Part 4: Content of free silica in dust (GBZ/T 192.4-2007) , the distribution of particulate of 5kinds of dust samples were observed. Different filter conditions were used to determinate the Content of free silica in the 4kinds ofdust samples: 1 filter paper, 2 filter papers, 3 filter papers, 2 filter papers with paper pulp in them. RESULTS: The distribution of particulate of 4 kinds of dust sampleswere different. The order from high to low is defined with "I, II, III, IV, V" successively. For dust sample I, II, III, the results with different conditions increase successively (P<0.05) . The result in 2 filter papers with paper pulp were not significantly different compared with the reference value (P>0.05) . For dust sample IV, the resultin 1 filter paper were significantlylower thanthe reference value (P<0.05) . For dust sampleV, The results with different kinds of filter type were not significantly different (P>0.05) . CONCLUSION: different filter conditions should be considered according to thecontent of free silica and the distribution of particulate in dust sample. For the dust sample which has the higher content of free silica and the distribution of particulate, 2 filter papers with paper pulp in themis the better filter condition compared with the traditional way.

PSORS2 is due to mutations in CARD14.

Psoriasis is a common, immune-mediated genetic disorder of the skin and is associated with arthritis in approximately 30% of cases. Previously, we localized PSORS2 (psoriasis susceptibility locus 2) to chromosomal region 17q25.3-qter after a genome-wide linkage scan in a family of European ancestry with multiple cases of psoriasis and psoriatic arthritis. Linkage to PSORS2 was also observed in a Taiwanese family with multiple psoriasis-affected members. In caspase recruitment domain family, member 14 (CARD14), we identified unique gain-of-function mutations that segregated with psoriasis by using genomic capture and DNA sequencing. The mutations c.349G>A (p.Gly117Ser) (in the family of European descent) and c.349+5G>A (in the Taiwanese family) altered splicing between CARD14 exons 3 and 4. A de novo CARD14 mutation, c.413A>C (p.Glu138Ala), was detected in a child with sporadic, early-onset, generalized pustular psoriasis. CARD14 activates nuclear factor kappa B (NF-kB), and compared with wild-type CARD14, the p.Gly117Ser and p.Glu138Ala substitutions were shown to lead to enhanced NF-kB activation and upregulation of a subset of psoriasis-associated genes in keratinocytes. These genes included chemokine (C-C motif) ligand 20 (CCL20) and interleukin 8 (IL8). CARD14 is localized mainly in the basal and suprabasal layers of healthy skin epidermis, whereas in lesional psoriatic skin, it is reduced in the basal layer and more diffusely upregulated in the suprabasal layers of the epidermis. We propose that, after a triggering event that can include epidermal injury, rare gain-of-function mutations in CARD14 initiate a process that includes inflammatory cell recruitment by keratinocytes. This perpetuates a vicious cycle of epidermal inflammation and regeneration, a cycle which is the hallmark of psoriasis.

Mutations in proteasome subunit ß type 8 cause chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature with evidence of genetic and phenotypic heterogeneity.

OBJECTIVE: Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE syndrome) is an autoinflammatory syndrome recently described in children. We undertook this study to investigate the clinical phenotype, genetic cause, and immune dysregulation in 9 CANDLE syndrome patients. METHODS: Genomic DNA from all patients was screened for mutations in PSMB8 (proteasome subunit ß type 8). Cytokine levels were measured in sera from 3 patients. Skin biopsy samples were evaluated by immunohistochemistry, and blood microarray profile and STAT-1 phosphorylation were assessed in 4 patients and 3 patients, respectively. RESULTS: One patient was homozygous for a novel nonsense mutation in PSMB8 (c.405C>A), suggesting a protein truncation; 4 patients were homozygous and 2 were heterozygous for a previously reported missense mutation (c.224C>T); and 1 patient showed no mutation. None of these sequence changes was observed in chromosomes from 750 healthy controls. Of the 4 patients with the same mutation, only 2 shared the same haplotype, indicating a mutational hot spot. PSMB8 mutation-positive and -negative patients expressed high levels of interferon-γ (IFNγ)-inducible protein 10. Levels of monocyte chemotactic protein 1, interleukin-6 (IL-6), and IL-1 receptor antagonist were moderately elevated. Microarray profiles and monocyte STAT-1 activation suggested a unique IFN signaling signature, unlike in other autoinflammatory disorders. CONCLUSION: CANDLE syndrome is caused by mutations in PSMB8, a gene recently reported to cause "JMP" syndrome (joint contractures, muscle atrophy, microcytic anemia, and panniculitis-induced childhood-onset lipodystrophy) in adults. We extend the clinical and pathogenic description of this novel autoinflammatory syndrome, thereby expanding the clinical and genetic disease spectrum of PSMB8-associated disorders. IFN may be a key mediator of the inflammatory response and may present a therapeutic target.

[Effects of glutamine induced heat shock protein 70 overexpression on atrial fibrosis and connexin 43 remodeling in isoprenaline-treated rats].

OBJECTIVE: To explore the effects of glutamine (Gln) induced heat shock protein 70(Hsp70) overexpression on atrial fibrosis and connexin 43 remodeling in isoprenaline(ISO)treated rats and related mechanisms. METHODS: Forty male SD rats were randomly divided into five groups (n = 8 each group): control group, DMSO group, ISO 5 mg×kg(-1)×d(-1) group (Fibrosis group), ISO 5 mg×kg(-1)×d(-1) + Ala-Gln 0.75 mg×kg(-1)×d(-1) group (Intervention group) and ISO 5 mg×kg(-1)×d(-1) + QUE 100 mg× kg(-1)×d(-1) + Ala-Gln 0.75 mg×kg(-1)×d(-1) + DMSO group (QUE group).Rats were killed after 7 d. The AngII expression in myocardial tissue was detected by radioimmunoassay; myocardial fibrosis was observed by HE staining.Collagen volume fractions were quantified by Masson staining and as the indicators of atrial fibrosis. The expressions of Hsp70, p-JNK1/2/3, c-Jun and Cx43 were determined with immunohistochemical method. RESULTS: AngII content was similar between the control group [(68.51 ± 10.76) pg/L] and DMSO [(71.47 ± 11.49) pg/L] group (P > 0.05), and significantly increased in fibrosis group [(211.25 ± 49.49) pg/L], intervention group [(185.32 ± 54.85) pg/L] and QUE [(189.90 ± 42.12) pg/L] group (P < 0.01 vs. control group). Atrial fibrosis was significantly higher in the fibrosis group [(29.485 ± 9.966)%] and QUE group [(25.060 ± 8.581)%] but not in the intervention group [(7.861 ± 1.867)%] compared to control group [(6.842 ± 1.674)%] and DMSO group [(7.108 ± 1.343)%]. The expression of Hsp70 was similar among the control group (0.160 ± 0.023), DMSO group (0.163 ± 0.022), fibrosis group (0.166 ± 0.028) and QUE (0.168 ± 0.027) group (P > 0.05) while significantly upregulated in the intervention group (0.215 ± 0.018) (P < 0.01 vs. control group). The expressions of p-JNK1/2/3 and c-Jun were similar between control group (0.151 ± 0.016;0.163 ± 0.022) and DMSO group (0.154 ± 0.021;0.164 ± 0.024)(P > 0.05), while significantly upregulated in fibrosis group (0.202 ± 0.025; 0.254 ± 0.044) and QUE group (0.196 ± 0.024; 0.251 ± 0.027) (P < 0.01 vs. control group) but not in intervention group (0.160 ± 0.025; 0.168 ± 0.024)were not changed obviously (P > 0.05 vs. control group). The content of Cx43 was similar between control group and DMSO group (0.231 ± 0.035 vs. 0.220 ± 0.032, P > 0.05), and was linearly distributed in intercalated disc of the cardiomyocytes, however, the content of Cx43 was significantly reduced (P < 0.01) and the Cx43 distribution was disordered in fibrosis group (0.163 ± 0.013) and QUE group (0.165 ± 0.024), while these changes were not found in intervention group. CONCLUSION: Glutamine could reduce the atrial fibrosis and Cx43 remodeling in isoprenaline-treated rats by up-regulating Hsp70 and inhibiting JNK signaling pathway activation through down-regulating p-JNK1/2/3 and c-Jun expression.

[Study of mechanical irritation effects in workers exposed to rock wool].

OBJECTIVE: To explore the effects of mechanical irritation to the skin, eyes, and upper respiratory tract in workers exposed to rock wool. METHODS: The gravimetric concentration of total dust and number concentration of fibre in the air of the rock wool workplace were determined . 109 rock wool manufacturing and processing workers were taken as the exposed group, 104 workers from an air separation plant, a papermaking plant and cover making plant were served as control group. All subjects accepted the questionnaire interview and clinical examination of the skin, eyes, nose and the pharynx. RESULTS: 10.1% of the exposed group had the irritant contact dermatitis, which showed linear trend with the current gravimetric concentration of total dust (P < 0.05) but no association with the exposure age (P > 0.05), and the detection rate of conjunctivitis of the exposed group (12.8%) was significantly higher than the control group (2.8%) (P < 0.05). The percentages of shin and eye itching symptoms of the exposed group (54.1% and 42.9%) were significantly higher than the control group (11.5% and 26.5%) (P < 0.05), but the differences among/between the exposed subgroups with different exposure level and different exposure age were not statistically significant (P > 0.05). The differences of the detection rate of chronic rhinitis and chronic pharyngitis and the percentages of the symptoms of nose and pharynx between the exposed group and control group were not statistically significant (P > 0.05), except the rhinorrhea symptom. CONCLUSIONS: Occupational exposure to rock wool had some degree of the mechanical irritation effects on the skin and eyes. The current exposure level of total dust should be emphatically controlled.

Study on Contrast-Enhanced Ultrasound Imaging and Anti-Tumor Effects of Drug-Loaded Nanodroplets with Tumor Targeting and Ultrasound Sensitivity.

BACKGROUND: Ultrasound-responsive nanodroplets (NDs) targeting tumors have shown great potential in ultrasound imaging and tumor therapy, but most of these studies are based NDs with lipid shells that cannot overcome the uptake by cells of the reticulo-endothelial system (RES). NDs with shells comprised of polyethylene glycol (PEG)-based polymers could effectively suppressed the uptake of RES, but the phase transition, contrast-enhanced imaging and drug release about these NDs have not been well illuminated. METHODS: Folate receptor targeted NDs with shells of polymers and loaded with DOX (FA-NDs/DOX) were prepared. The particle size distribution and morphology of NDs was characterized with dynamic light scattering (DLS) and microscope. Phase transition and contrast-enhanced ultrasound imaging under different mechanical indices (MIs) was studied, and the intensity of contrast enhancement were quantitatively analyzed. The targeting property of FA-NDs/DOX to MDA-MB-231 cells and cellular uptake were observed using a fluorescence microscope. The anti-tumor effects of FA-NDs/DOX combined with low-intensity focused ultrasound (LIFU) was studied through cytotoxicity tests. Flow cytometry assays were used to detect cell apoptosis. RESULTS: The average particle size of the FA-NDs/DOX was 448.0 ± 8.9 nm, and the zeta potential was 30.4 ± 0.3 mV. When exposed to ultrasound at 37 °C, ultrasound contrast enhancement of FA-NDs/DOX was observed when MI ≥0.19. A stronger acoustic signal was observed under higher MIs and concentrations. The results of quantitative analysis showed that the contrast enhancement intensity of FA-NDs/DOX (1.5 mg/mL) at MI of 0.19, 0.29 and 0.48 was 26.6 ± 0.9 dB, 97.0 ± 3.8 dB and 153.1 ± 5.7 dB, respectively. The contrast enhancement of the FA-NDs/DOX lasted for more than 30 minutes at an MI of 0.48. In targeting experiments, FA-NDs could be recognized by MDA-MB-231 cells, and significant cellular uptake was observed. The blank FA-NDs showed good biocompatibility, while the FA-NDs/DOX induced apoptosis of MDA-MB-231 and MCF-7 cells. By combining LIFU irradiation and FA-NDs/DOX treatment, the best cell-killing effect was achieved. CONCLUSIONS: The FA-NDs/DOX prepared in this study has excellent performance in contrast-enhanced ultrasound imaging, tumor targeting and enhanced chemotherapy. This FA-NDs/DOX with polymer shells provides a novel platform for ultrasound molecular imaging and tumor therapy.

Effects of water chemistry on microfabric and micromechanical properties evolution of coastal sediment: A centrifugal model study.

Water chemistry alteration induced strength weakening of natural sediment, which leads to the differential settlement of infrastructures in coastal areas, has caused numerous disasters and engineering failures. To thoroughly understand the underlying mechanisms of how water chemistry influences the microfabric and mechanical properties evolution of coastal sediments, herein, the authors adopted centrifuge test, X-ray diffraction (XRD), and atomic force microscope (AFM) to quantitatively study the structure anisotropy index (i.e., orientation index (OI)), micromorphological property (i.e., root mean square height (Sq)), and micromechanics (i.e., microscale apparent modulus) of clay sediments in different water chemistry conditions and gravity gradients. The results show that the change rule of OI is: OIsaline > OIalkaline > OIwater > OIacid, along the vertical sedimentary depth. Randomly distributed clay flocs and loose flocculated soil skeleton (mainly consisted by edge-to-face (EF) and edge-to-edge (EE) contact of the kaolinite platelets) are associated with the acidic water chemical conditions. The action of supergravity and face-to-face (FF) repulsive contact mode lead to high degree of anisotropy of kaolinite sediments in alkaline environment. Clay platelets are compacted closely under the synergetic effect of centrifugal pressure and prevailing van der Waals attraction (reduction of electric double layer repulsion) in saline environment. The change of 1/Sq is highly consistent with the change of OI at different depths in different water chemical environments. Along the sedimentary depth (i.e., transition from the normal gravity (1 g) to supergravity (8000 g)), the microscale apparent modulus of kaolinite sediment was found to be the highest in alkaline environment. As the water chemistry changes from alkaline to acidic, however, the microscale apparent modulus of kaolinite aggregate decreased, and it showed the smallest in the saline environment.

Effects of resveratrol on tolerance to ischemia/reperfusion injury in aged male mice: Role of autophagy and apoptosis.

Aged myocardium is more susceptible to ischemia/reperfusion (I/R) injury. Autophagy and apoptosis play important roles in cardiac I/R injury. However, whether resveratrol can reduce the I/R vulnerability of aged myocardium by regulating apoptosis and autophagy remains unclear. The present study aimed to investigate the effect of resveratrol on the tolerance to I/R injury in aged male mice and to determine the contribution of apoptosis and autophagy. We used aged C57 mice as our research subjects. The hearts of mice were isolated after 6 weeks of intragastric administration with resveratrol and subsequently perfused with Krebs-Henseleit buffer to produce the I/R model. We found that resveratrol alleviated cardiac I/R injury in aged mice, but not in SIRT1+/- mice. Aged mice exhibited decreased LC3 and Beclin1 expressions, which were significantly rescued by resveratrol treatment. In addition, resveratrol decreased the expression of Bax and the activity of Caspase-3, while increasing the expression of Bcl-2 and the activity of SIRT1 in aged mouse hearts. Coimmunoprecipitation assays revealed that resveratrol facilitated the binding of Bax to Bcl-2 and the dissociation of Bcl-2 from Beclin1 in aged mouse myocardium. Conversely, SIRT1 knockout enhanced the formation of the Beclin1/Bcl-2 complex and disrupted the interaction between Bcl-2 and Bax. The above results indicate that resveratrol can reduce the vulnerability of myocardial I/R injury in senile myocardium by inhibiting apoptosis and upregulating autophagy through the SIRT1 signaling pathway.