The impact of n-hexane on the secretion of mouse estrogen and progesterone

Aim: To study the toxic effect of n-hexane on sex hormone levels, including its effect on ovarian sex hormone secretion levels and the underlying mechanism. 1) In vivo experiment: The mice were exposed to n- hexane by static inhalation of doses of 0, 3.0, 15.1 or 75.8 ml/m3 once a day (4 hours), 7 days a week, for 5 consecutive weeks. After exposure, mouse sera were sampled to measure estradiol (E2) and progesterone (P4) levels by electrochemiluminescence immunoassays (ECLIA). 2) In vitro experiment: mice at different stages of the estrous cycle were sacrificed and their minced tissue pieces were incubated in medium containing hexane-2,5-dione (2,5-HD). Then, the E2 and P4 levels in the media were measured by ECLIA. In vivo assays, the serum P4 levels in each group were lower than the control group, which was statistically significant (F = 6.196, P 2 level of 75.8 mL/m3 dosage group was decreased (96.9522 ± 7.8652)) compared to the control group (119.1600 ± 25.6420), with statistical significance (P 4 levels of 15.1 mL/m3 and 75.8 mL/m3 dosage groups were also decreased (18.5938 ± 12.485pmol/L, 13.5550 ± 5.7789 pmol/L) and were statistically significantly (F = 6.196, P In vitro, the E2 levels at various stages of the estrous cycle were significantly different from the control groups (P In vitro, different concentrations of 2, 5-HD significantly inhibited the P4 level (P 4 levels at various stages of the estrous cycle were also significantly different from controls (P 0.05). The results indicate that n-hexane may inhibit release of ovarian E2 and P4, which may be the main reason for the interference of the reproductive endocrine system by n-hexane.

3D spiral channels combined with flexible micro-sieve for high-throughput rare tumor cell enrichment and assay from clinical pleural effusion samples

The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,purification,as well as viability rates of rare target cells as the prerequisites for high sensitivity,specificity,and accuracy of tumor cell analysis.In this paper,we propose a three-dimensional(3 D)sieving method for rare tumor cell enrichment,which effectively eliminates the"dead zones"in traditional two-dimensional(2 D)cell filters with a dimension-raising strategy to satisfy the requirements mentioned above.The prototype device was combined with a funnel-shaped holder,a flexible micropore membrane in the middle,and a3 D spiral fluid channel covered on the membrane as a three-layer ice-creaming cone composite structure.Driven by gravity alone,the device performed as follows:(1)20-fold throughput compared with the 2 D commercial planee hich was up to 20 mL/min for a threefold dilution of whole blood sample;(2)high recovery rates of 84.5%±21%,86%±25%,83%±14%for 100,1000,and 10000 cells/mL,respectively,in 30 mL phosphate buffer saline(PBS)sample,and a 100%positive detection rate in the case of≤5 A549 cells in 1 mL PBS;(3)a typical purification rate of 85.5%±9.1%;and(4)a viability rate of>93%.In the demonstration application,this device effectively enriched rare target cells from large volumes(>25 mL)of clinical pleural effusions.The following results indicated that tumor cells were easy-to-discover in the enriched PE samples,and the proliferation capability of purified cells was(>4.6 times)significantly stronger than that of unprocessed cells in the subsequent 6-day culture.The above evaluation indicates that the proposed easily reproducible method for the effective execution of rare cell enrichments and assays is expected to become a practical technique for clinical cell-based tumor diagnosis.

piRT-IFC:Physics-informed real-time impedance flow cytometry for the characterization of cellular intrinsic electrical properties

Real-time transformation was important for the practical implementation of impedance flow cytometry.The major obstacle was the time-consuming step of translating raw data to cellular intrinsic electrical properties(e.g.,specific membrane capacitance C_(sm) and cytoplasm conductivityσ_(cyto)).Although optimization strategies such as neural network-aided strategies were recently reported to provide an impressive boost to the translation process,simultaneously achieving high speed,accuracy,and generalization capability is still challenging.To this end,we proposed a fast parallel physical fitting solver that could characterize single cells’C_(sm)andσ_(cyto)within 0.62 ms/cell without any data preacquisition or pretraining requirements.We achieved the 27000-fold acceleration without loss of accuracy compared with the traditional solver.Based on the solver,we implemented physics-informed real-time impedance flow cytometry(piRT-IFC),which was able to characterize up to 100,902 cells’C_(sm) andσ_(cyto)within 50 min in a real-time manner.Compared to the fully connected neural network(FCNN)predictor,the proposed real-time solver showed comparable processing speed but higher accuracy.Furthermore,we used a neutrophil degranulation cell model to represent tasks to test unfamiliar samples without data for pretraining.After being treated with cytochalasin B and N-Formyl-Met-Leu-Phe,HL-60 cells underwent dynamic degranulation processes,and we characterized cell’s C_(sm)andσ_(cyto)using piRT-IFC.Compared to the results from our solver,accuracy loss was observed in the results predicted by the FCNN,revealing the advantages of high speed,accuracy,and generalizability of the proposed piRT-IFC.

Asynchronous Brain-Computer Interface Shared Control of Robotic Grasping

The control of a high Degree of Freedom(DoF) robot to grasp a target in three-dimensional space using Brain-Computer Interface(BCI) remains a very difficult problem to solve. Design of synchronous BCI requires the user perform the brain activity task all the time according to the predefined paradigm; such a process is boring and fatiguing. Furthermore, the strategy of switching between robotic auto-control and BCI control is not very reliable because the accuracy of Motor Imagery(MI) pattern recognition rarely reaches 100%. In this paper, an asynchronous BCI shared control method is proposed for the high DoF robotic grasping task. The proposed method combines BCI control and automatic robotic control to simultaneously consider the robotic vision feedback and revise the unreasonable control commands. The user can easily mentally control the system and is only required to intervene and send brain commands to the automatic control system at the appropriate time according to the experience of the user. Two experiments are designed to validate our method: one aims to illustrate the accuracy of MI pattern recognition of our asynchronous BCI system; the other is the online practical experiment that controls the robot to grasp a target while avoiding an obstacle using the asynchronous BCI shared control method that can improve the safety and robustness of our system.

Preparation of carboxylmethylchitosan and alginate blend membrane for diffusion-controlled release of diclofenac diethylamine

Controlled drug release technology is becoming a commercially sound methodology of administering pharmaceutical therapies,and it is important to predict and control the release kinetics to fully take advantage of this technology.Carboxylmethylchitosan(CMCS)and alginate(SA)blend membranes were successfully prepared by solution casting technique and exposing to acetic acid atmosphere,which induced the protonation of the amino groups of CMCS,and the formation of polyelectrolyte composite hydrogels.By using diclofenac diethylamine as the model drug,the diffusion controlled drug release behaviors of the membranes were studied based on permeation experiment,which indicated that the swelling rates of the membranes could be adjusted by simply changing the weight ratio of CMCS/SA and effectively changed the release rate of the membrane.The study shows that CMCS/SA blend membranes are promising biomaterials used for modulating the permeation behavior and developing advanced drug delivery systems.

A review of EEG-based brain-computer interface systems design

A brain-computer interface(BCI) system can recognize the mental activities pattern by computer algorithms to control the external devices. Electroencephalogram(EEG) is one of the most common used approach for BCI due to the convenience and non-invasive implement. Therefore, more and more BCIs have been designed for the disabled people that suffer from stroke or spinal cord injury to help them for rehabilitation and life. We introduce the common BCI paradigms, the signal processing, and feature extraction methods. Then, we survey the different combined modes of hybrids BCIs and review the design of the synchronous/asynchronous BCIs.Finally, the shared control methods are discussed.

Efficient nanostructured heterogeneous catalysts by electrochemical etching of partially crystallized Fe-based metallic glass ribbons

Although an increasing interest has been attracted to further develop heterostructured catalysts from metallic glasses(MGs) by heat treatment, overcoming surface oxidation effect is still a critical problem for such environmental catalysts. Herein, a short-time electrochemical etching of partially crystallized Febased ribbons in 0.3 M H3 PO4 electrolyte enables the formation of honeycomb-like nanoporous structure as effective catalytic active sites in Fenton-like process. Studies of structure and surface morphologies reveal that the formation of nanoporous structure by potentiostatic etching originates from electrochemical potential difference of nanocrystals(a-Fe(Si) and Fe2 B) and residual amorphous phase in partially crystallized ribbons, where Fe2 B having a lower open circuit potential tends to be selectively dissolved.Simultaneously, thin oxide layer after electrochemical etching exposes more active sites for H2 O2 activation and provides an effective protection of nanocrystals from massive loss during etching. Investigation of optimal processing conditions suggests that the selection of electrolyte plays an important role;dye degradation rates of etched ribbons in HNO3 and Na2 SO4 electrolytes can also achieve at least 2 times higher than that of as-annealed ribbons. This work holds the promise to develop novel environmental catalysts by effective electrochemical etching of partially crystallized ribbons.