Differential proteomic analysis demonstrates follicle fluid participate immune reaction and protein translation in yak.

BACKGROUND: Ovarian follicle fluid (FF) as a microenvironment surrounding oocyte plays critical roles in physio-biochemical processes of follicle development and oocyte maturation. It is hypothesized that proteins in yak FF participate in the physio-biochemical pathways. The primary aims of this study were to find differentially expressed proteins (DEPs) between mature and immature FF, and to elucidating functions of the mature and immature FF in yak. RESULTS: The mature and immature FF samples were obtained from three healthy yaks that were nonpregnant, aged from four to five years, and free from any anatomical reproductive disorders. The FF samples were subjected to mass spectrometry with the isobaric tags for relative and absolute quantification (iTRAQ). The FF samples went through correlation analysis, principle component analysis, and expression pattern analysis based on quantification of the identified proteins. Four hundred sixty-three DEPs between mature and immature FF were identified. The DEPs between the mature and immature FF samples underwent gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and protein-protein interaction (PPI) analysis. The DEPs highly expressed in the mature FF mainly took parts in the complement and coagulation cascades, defense response, acute-phase response, response to other organism pathways to avoid invasion of exogenous microorganisms. The complement activation pathway contains eight DEPs, namely C2, C5, C6, C7, C9, C4BPA, CFH, and MBL2. The three DEPs, CATHL4, CHGA, and PGLYRP1, take parts in defense response pathway to prevent invasion of exogenetic microorganism. The coagulation cascades pathway involves many coagulation factors, such as F7, F13A1, FGA, FGB, FGG, KLKB1, KNG1, MASP1, SERPINA1, and SERPIND1. While the DEPs highly expressed in the immature FF participated in protein translation, peptide biosynthetic process, DNA conformation change, and DNA geometric change pathways to facilitate follicle development. The translation pathway contains many ribosomal proteins, such as RPL3, RPL5, RPS3, RPS6, and other translation factors, such as EIF3J, EIF4G2, ETF1, MOV10, and NARS. The DNA conformation change and DNA geometric change involve nine DEPs, DDX1, G3BP1, HMGB1, HMGB2, HMGB3, MCM3, MCM5, MCM6, and RUVBL2. Furthermore, the expressed levels of the main DEPs, C2 and SERPIND1, were confirmed by western blot. CONCLUSIONS: The differential proteomics revealed the up-regulated DEPs in mature FF take parts in immunoreaction to prevent invasion of microorganisms and the up-regulated DEPs in immature FF participate in protein synthesis, which may improve our knowledge of the follicular microenvironment and its biological roles for reproductive processes in yak. The DEPs, C2 and SERPIND1, can be considered as protein markers for mature yak follicle.

A bio-inspired two-stage bionic drag reduction method.

Reducing the surface resistance of underwater vehicles plays an important role in improving cruising speed and cruising mileage. The epidermis of loaches is not only covered with a layer of scale structure but also secretes mucus tissue with a lubricating effect, which makes loaches swim rapidly in muddy water. Study the morphology and structure of the skin of loach and establish a two-stage biomimetic drag reduction model. Adjust the different structural parameters of the model and select the parameters with the best drag reduction rate for the modeling design. The numerical simulation results show that the optimal drag reduction rate of the two-stage drag reduction structure is greater than 21%. In the flow channel test experiment, the drag reduction rate is slightly lower than the simulation results. Numerical simulation and experimental data show that the underwater drag reduction function can be realized by simulating the microstructure of loach skin. Finally, analyze the velocity gradient, vortices, etc., and search for the drag reduction mechanism. The simulation design of the microstructure of the loach skin can increase the thickness of the boundary layer, promote the vortex structure near the wall surface, change the flow mode of the solid-liquid interface, and reduce the wall resistance. At the same time, the drag reduction model provides key technical support for the practical application of reducing surface resistance, such as in underwater vehicles.

Near-Field Microwave Imaging Method of Monopole Antennas Based on Nitrogen-Vacancy Centers in Diamond.

Visualizing the near-field distribution of microwave field in a monopole antenna is very important for antenna design and manufacture. However, the traditional method of measuring antenna microwave near field distribution by mechanical scanning has some problems, such as long measurement time, low measurement accuracy and large system volume, which seriously limits the measurement effect of antenna microwave near field distribution. In this paper, a method of microwave near-field imaging of a monopole antenna using a nitrogen-vacancy center diamond is presented. We use the whole diamond as a probe and camera to achieve wide-field microwave imaging. Because there is no displacement structure in the system, the method has high time efficiency and good stability. Compared with the traditional measurement methods, the diamond probe has almost no effect on the measured microwave field, which realizes the accurate near-field imaging of the microwave field of the monopole antenna. This method achieves microwave near-field imaging of a monopole antenna with a diameter of 100 µm and a length of 15 mm at a field of view of 5 × 5 mm, with a spatial resolution of 3 µm and an imaging bandwidth of 2.7~3.2 GHz, and an optimal input microwave phase resolution of 0.52° at a microwave power of 0.8494 W. The results provide a new method for microwave near-field imaging and measurement of monopole antennas.

A Bio-Inspired Drag Reduction Method of Bionic Fish Skin Mucus Structure.

Efforts to enhance the speed and reduce the energy consumption of underwater vehicles have led to the proposal of a novel mucus release structure inspired by the secretion of mucus cells on fish skin. This structure features interconnected microgrooves with excellent flexibility for adjusting to different states, effectively reducing drag through mucus release. Numerical analysis of the drag reduction performance of the mucous-releasing micro-pore structure was conducted using ANSYS Fluent 19.2 software. This structure is capable of reducing the velocity gradient near the wall and, owing to the presence of micro-pore structures, decreasing the overall compressed area, thereby achieving drag reduction effects. The experimental results revealed a drag reduction effect of 20.56% when the structure was bent at an angle of 120°. The drag reduction varied under different attitudes such as tension and compression. This mucus release structure achieves reusability through a direct mucous injection process. This research provides valuable insights for the drag reduction study of underwater vehicles, such as ships and submarines, laying a foundation for advancing the development and applications of this field in the future.

A dual-targeting antifungal is effective against multidrug-resistant human fungal pathogens.

Drug-resistant fungal infections pose a significant threat to human health. Dual-targeting compounds, which have multiple targets on a single pathogen, offer an effective approach to combat drug-resistant pathogens, although ensuring potent activity and high selectivity remains a challenge. Here we propose a dual-targeting strategy for designing antifungal compounds. We incorporate DNA-binding naphthalene groups as the hydrophobic moieties into the host defence peptide-mimicking poly(2-oxazoline)s. This resulted in a compound, (Gly0.8Nap0.2)20, which targets both the fungal membrane and DNA. This compound kills clinical strains of multidrug-resistant fungi including Candida spp., Cryptococcus neoformans, Cryptococcus gattii and Aspergillus fumigatus. (Gly0.8Nap0.2)20 shows superior performance compared with amphotericin B by showing not only potent antifungal activities but also high antifungal selectivity. The compound also does not induce antimicrobial resistance. Moreover, (Gly0.8Nap0.2)20 exhibits promising in vivo therapeutic activities against drug-resistant Candida albicans in mouse models of skin abrasion, corneal infection and systemic infection. This study shows that dual-targeting antifungal compounds may be effective in combating drug-resistant fungal pathogens and mitigating fungal resistance.

Robustness improvement of a nitrogen-vacancy magnetometer by a double driving method.

The nitrogen vacancy (NV) color center in diamonds is an electron spin that can measure magnetic fields with high sensitivity and resolution. Furthermore, the robustness of an NV-based quantum system should be improved for further application in other sensing methods and in the exploration of basic physics. In this work, the robustness of an NV magnetometer is improved by the double driving method. The sensitivity of the NV magnetometer was improved 2.1 times by strengthening the pumping power from 100 to 600 mW. In this process, thermal drift was introduced, which affects the measurement accuracy. The temperature drift of a diamond matrix was measured using an infrared camera, and the temperature change of a diamond host drifted to ∼80 K under high laser and microwave power. To address the drift of temperature owing to sensitivity improvement by pumping enhancement, the double driving method was introduced, to suppress the drift of the resonance frequency, to improve the robustness of a continuous-wave NV magnetometer. The magnetic noise density was improved from 10 to 1.2 nT/Hz1/2. This study checked the source of temperature noise in the process of measuring with the NV color centers and proposes a double driving measurement method to track the resonant frequency change due to environmental temperature drift and improve sensitivity. The findings of this study are useful in applying complex pulse protocols in high-level sensing applications based on solid-state spin.

Convenient and Controllable Synthesis of Poly(2-oxazoline)-Conjugated Doxorubicin for Regulating Anti-Tumor Selectivity.

Polyethylene glycol (PEG)-doxorubicin (DOX) conjugation is an important strategy to improve toxicity and enhance clinically therapeutic efficacy. However, with the frequent use of PEG-modified drugs, the accumulation of anti-PEG antibodies has become a tough issue, which limits the application of PEG-drug conjugation. As an alternative solution, poly(2-oxazoline) (POX)-DOX conjugation has shown great potential in the anti-tumor field, but the reported conjugation process of POX with DOX has drawbacks such as complex synthetic steps and purification. Herein, we propose a convenient and controllable strategy for the synthesis of POX-DOX conjugation with different chain lengths and narrow dispersity by N-boc-2-bromoacetohydrazide-initiated 2-ethyl-oxazoline polymerization and the subsequent deprotection of the N-Boc group and direct reaction with DOX. The DOX-PEtOx conjugates were firstly purified, and the successful conjugations were confirmed through various characterization methods. The synthetic DOX-PEtOxn conjugates reduce the toxicity of DOX and increase the selectivity to tumor cells, reflecting the promising application of this POX-DOX conjugation strategy in drug modification and development.

Host defense peptide mimicking cyclic peptoid polymers exerting strong activity against drug-resistant bacteria.

Extensive use of antibiotics accelerates the emergence of drug-resistant bacteria and related infections. Host defense peptides (HDPs) have been studied as promising and potential therapeutic candidates. However, their clinical applications of HDPs are limited due to their high cost of synthesis and low stability upon proteolysis. Therefore, HDP mimics have become a new approach to address the challenge of bacterial resistance. In this work, we design the amphiphilic peptoid polymers by mimicking the positively charged and hydrophobic structures of HDPs and synthesize a series of cyclic peptoid polymers efficiently via the polymerization on α-amino acid N-substituted glycine N-carboxyanhydrides (α-NNCAs) using 1,8-diazabicycloundec-7-ene (DBU) as the initiator. The optimal cyclic peptoid polymer, poly(Naeg0.7Npfbg0.3)20, displays strong antibacterial activities against drug-resistant bacteria, but low hemolysis and cytotoxicity. In addition, the mode-of-action study indicates that the antibacterial mechanism is associated with bacterial membrane interaction. Our study implies that HDP mimicking cyclic peptoid polymers have potential application in treating drug-resistant bacterial infections.

Effect of Catgut Embedment in Du Meridian Acupoint on Mental and Psychological Conditions of Patients with Gastroesophageal Reflux Disease.

OBJECTIVE: To observe the influence of the catgut-embedding method in Du Meridian acupoint on the mental and psychological state of patients with gastroesophageal reflux disease (GERD) and analyze its possible mechanism. METHODS: According to the random number table, 60 patients with GERD were randomly divided into groups of acupoint catgut embedding and Western medicine, 30 cases in each group. The acupoint group was given catgut embedment in the positive reaction points along the Du Meridian, while the Western medicine group received lansoprazole tablet. They were both treated for six weeks. Scores of Gastroesophageal Reflux Disease Questionnaire (GerdQ), Zung's Self-Rating Anxiety Scale (SAS), Zung's Self-Rating Depression Scale (SDS), and Health-Related Quality of Life Scale for GERD (GERD-HRQL) were measured before and after treatment to analyze and evaluate the differences of symptom scores and mental and psychological conditions between the two groups. RESULTS: (1) The scores of GerdQ, GERD-HRQL, SAS, and SDS in the two groups both significantly decreased after treatment (P < 0.05), and those of the acupoint group were much lower than the Western medicine group (P < 0.05). (2) The total effective rate was 90.00% in the acupoint group and 53.33% in the Western medicine group, with a statistically significant difference (P < 0.05). (3) The correlation coefficients r between the GerdQ score and scores of SAS and SDS were 0.563 and 0.322, respectively, and those between the GERD-HRQL score and scores of SAS and SDS were, respectively, 0.506 and 0.435. CONCLUSION: (1) The main symptoms of GERD patients, such as acid reflux and heartburn, mental and psychological condition, and quality of life, were all improved in the two groups, but the efficacy in the acupoint group is superior to that of the Western medicine group. (2) The clinical symptoms and scores of patients' quality of life are positively correlated with the degree of their anxiety and depression. (3) The acupoint catgut-embedding method can effectively regulate the anxiety and depressive symptoms of patients, which complements the efficacy of proton-pump inhibitors and benefits a wider range of population.

[Effects of sea water temperature and salinity on the growth and survival of juvenile Meretrix meretrix Linnaeus].

A laboratory test was conducted to study the effects of different sea water temperature (17 grads) and salinity (19 grads) on the growth and survival of juvenile Meretrix meretrix. The suitable and optimum sea water salinities for the survival of juvenile M. meretrix were 6.5-39.5 and 9.0-31.0, and those for the juvenile growth were 7.3-38.7 and 15.0-23.0, respectively. The suitable sea water temperature for the survival of the juveniles was 4.0 degrees C-36.1 degrees C; the suitable temperature for the growth was 7.0 degrees C-35.4 degrees C, more suitable temperature was 17 degrees C-33.5 degrees C, and the optimum growth temperature was 24 degrees C-27 degrees C. Juvenile M. meretrix had stronger adaptability to high sea water temperature and low sea water salinity.