Studies on Electrical Activation of Porcine Oocytes Matured in vitro and Embryo Culture Systems

Conditions for electrical parthenogenetic activation of porcine oocytes matured in vitro and in vitro culture systems of porcine embryo were studied. The best results were achieved under the conditions of electrical field strength and the pulse duration at 130Vmm-1/80 us, with a blastocyst development rate of (20.12 ± 8.18) % (P > 0.05). No significant difference was found between treatments of multiple pulses and a single pulse (P > 0.05). Parthenogenetic embryos were cultured with different methods and air conditions for 7 days in vitro, blastocyst development rate of embryos with changed culture media [ (26.44 ± 8.35) % ] or changed media with 10% fetal bovine serum (FBS) [ (17.68 ± 5.39)% ] on the fifth day showing no significant difference from that of embryos without change of culture media [ (25.30 ± 7.55) % , P > 0.05 ], while cell numbers of blastocysts from embryos with changed culture media (15.78 + 5.46 and 14.55 ± 4.81) were significantly lower than number of blastocysts from embryos without change of culture media (18.01 ± 6.79, P<0.01). Blastocyst development rate and blastocyst cell number of embryos cultured in lower O2(5%CO2: 7%O2:88%N2) also showed no significant difference from those in high O2(5%CO2 in air) [(20.78 ± 8. 80)% and 17.0016.12 vs. (25.30 ± 7.55)% and 18.0116.79, P>0.05]. It is concluded that change of culture media with the same new one or changing over to media with 10% fetal bovine serum (FBS) on the fifth day and low O2 environment are not necessary for porcine embryos development.

Translocation of telomerase reverse transcriptase coincided with ATP release in postnatal cochlear supporting cells

The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period.

Comparison of detection results of hypoxic-ischemic encephalopathy at different degrees in infant patients between brain electrical activity mapping, transcranial Doppler sonography and computer tomography examinations

BACKGROUND： It has been proved that brain electrical activity mapping （BEAM） and transcranial Doppler （TCD） detection can reflect the function of brain cell and its diseased degree of infant patients with moderate to severe hypoxic-ischemic encephalopathy （HIE）. OBJECTIVE： To observe the abnormal results of HIE at different degrees detected with BEAM and TCD in infant patients, and compare the detection results at the same time point between BEAM, TCD and computer tomography （CT） examinations. DESIGN ： Contrast observation SETTING： Departments of Neuro-electrophysiology and Pediatrics, Second Affiliated Hospital of Qiqihar Medical College. PARTICIPANTS： Totally 416 infant patients with HIE who received treatment in the Department of Newborn Infants, Second Affiliated Hospital of Qiqihar Medical College during January 2001 and December 2005. The infant patients, 278 male and 138 female, were at embryonic 37 to 42 weeks and weighing 2.0 to 4.1 kg, and they were diagnosed with CT and met the diagnostic criteria of HIE of newborn infants compiled by Department of Neonatology, Pediatric Academy, Chinese Medical Association. According to diagnostic criteria, 130 patients were mild abnormal, 196 moderate abnormal and 90 severe abnormal. The relatives of all the infant patients were informed of the experiment. METHOOS： BEAM and TCD examinations were performed in the involved 416 infant patients with HIE at different degrees with DYD2000 16-channel BEAM instrument and EME-2000 ultrasonograph before preliminary diagnosis treatment （within 1 month after birth） and 1,3,6,12 and 24 months after birth, and detected results were compared between BEAM, TCD and CT examinations. MAIN OUTCOME MEASURES： Comparison of detection results of HIE at different time points in infant patients between BEAM. TCD and CT examinations. RESULTS： All the 416 infant patients with HIE participated in the result analysis. （1） Comparison of the detected results in infant patients with mild HIE at different time points after birth between BEAM, TCD and CT examinations： BEAM examination showed that the recovery was delayed, and the abnormal rate of BEAM examination was significantly higher than that of CT examination 1 and 3 months after birth [55.4%（72/130）vs. 17.0% （22/130 ）,x^2=41.66 ;29.2% （ 38/130 ） vs. 6.2% （ 8/130 ）, x^2=23.77, P 〈 0.01 ], exceptional patients had mild abnormality and reached the normal level in about 6 months. TCD examination showed that the disease condition significantly improved and infant patients with HIE basically recovered 1 or 2 months after birth, while CT examination showed that infant patients recovered 3 or 4 months after birth. （2） Comparison of detection results of infant patients with moderate HIE at different time points between BEAM, TCD and CT examinations： The abnormal rate of BEAM examination was significantly higher than that of CT examination 1,3,6 and 12 months after birth [90.8% （178/196）,78.6% （154/196）,x^2=4.32,P 〈 0.05;64.3% （126/196）,43.9% （86/196） ,x^2=16.44 ;44.9% （88/196） ,22.4% （44/196）,x^2=22.11 ;21.4% （42/196）, 10.2% （20/196）,x^2=9.27, P 〈 0.01]. BEAM examination showed that there was still one patient who did not completely recovered in the 24^th month due to the relatives of infant patients did not combine the treatment,. TCD examination showed that the abnormal rate was 23.1%（30/196）in the 1^st month after birth, and all the patients recovered to the normal in the 3^rd month after birth, while CT examination showed that mild abnormality still existed in the 24^th month after birth （1.0% ,2/196）. （3） Comparison of detection results of infant patients with severe HIE at different time points between BEAM, TCD and CT examinations： The abnormal rate of BEAM examination was significantly higher than that of CT examination in the 1^st, 3^rd, 6^th and 12^th months after birth[86.7% （78/90）,44.4% （40/90）,x^2=35.53;62.2% （56/90）,31.1% （28/90）,x^2=17.51 ;37.8% （34/90）,6.7% （6/90）, x^2=27.14, P 〈 0.01]. BEAM examination showed that mild abnormality still existed in 4 infant patients in the 24^th month after birth. TCD examination showed that the abnormal rate was 11.1% （10/90） in the 3^rd month after birth, and all the infant patients recovered in the 6^th month after birth. CT examination showed that the abnormal rate was 6.7%（6/90） in the 12^th month after birth, and all of infant patients recovered to the normal in the 24^th month after birth.CONCLUSION ： BEAM is the direct index to detect brain function of infant patients with HIE, and positive reaction is still very sensitive in the tracking detection of convalescent period. The positive rate of morphological reaction in CT examination is superior to that in TCD examination, and the positive rate is very high in the acute period of HIE in examination.

Studies on Nuclear Transplantation in Mammalian Embryos

A series of experiments were conducted to study the major procedures in nuclear transplantation such as oocyte enucleation and activation, electrofusion and developnent of the nuclear transplant embryos in the mouse, rabbits and sheep. The important results are as follows:11. In the mouse, only 35% of the oocytes collected 15～16 h after hCG had a notable first polar body (FPb) and those without FPb were enucleated by removing cytoplasm from the PVS-wider side and the enucleation rate was similar to that in the oocytes with FPb, and the enucleation rate of removing 1/3 cytoplasm was remarkably higher than that of removing 1/4 cytoplasm. 2. Among the three fusion media tested, mannitol and sucrose solutions produced better results than M2 in electrofusion of mouse 2-cell embryos. Under favorable pulse conditions, the osmotic pressure of fusion medium had no motable effect on electrofusion, but as the conditions became so unfavorable that some embryos began to lyse, the fusion rates in hypertonie mannitol solution were significantly higher than those in isotonic or hypotonic solutions. A wide range of pulse strengths (0.31～2.04 by/ cm) and durations(10～1280 μs) were used and 100% of fusion were obtained in many cases. Optimal pulse durations were plotted for field strengths to obtain high fusion rates (96%～ 100%) in mouse2-cell embryos. 3. With one pulse of 0.45 by / cm, satisfactory results of mouse oocyte activation were obtained only when the duration increased to 160 μs or longer. The activation rate increased as the oocytes got older. Some of the oocytes ar. rested at metaphase Ⅲ after electrical stimulation and their proportion to the number of oocytes not activated increased with egg age. 4. 10% and 31% of the nuclear transplant embryos developed to morula or blastocyst stage in sheep and rabbits, respectively, with Chinese-made hormones and chemicals.

Differential development and electrophysiological activity in cultured cortical neurons from the mouse and cynomolgus monkey

In vitro cultures of primary cortical neurons are widely used to investigate neuronal function.However,it has yet to be fully investigated whether there are significant differences in development and function between cultured rodent and primate cortical neurons,and whether these differences influence the utilization of cultured cortical neurons to model pathological conditions.Using in vitro culture techniques combined with immunofluorescence and electrophysiological methods,our study found that the development and maturation of primary cerebral cortical neurons from cynomolgus monkeys were slower than those from mice.We used a microelectrode array technique to compare the electrophysiological differences in cortical neurons,and found that primary cortical neurons from the mouse brain began to show electrical activity earlier than those from the cynomolgus monkey.Although cultured monkey cortical neurons developed slowly in vitro,they exhibited typical pathological features-revealed by immunofluorescent staining-when infected with adeno-associated viral vectors expressing mutant huntingtin(HTT),the Huntington’s disease protein.A quantitative analysis of the cultured monkey cortical neurons also confirmed that mutant HTT significantly reduced the length of neurites.Therefore,compared with the primary cortical neurons of mice,cultured monkey cortical neurons have longer developmental and survival times and greater sustained physiological activity,such as electrophysiological activity.Our findings also suggest that primary cynomolgus monkey neurons cultured in vitro can simulate a cell model of human neurodegenerative disease,and may be useful for investigating time-dependent neuronal death as well as treatment via neuronal regeneration.All mouse experiments and protocols were approved by the Animal Care and Use Committee of Jinan University of China(IACUC Approval No.20200512-04)on May 12,2020.All monkey experiments were approved by the IACUC protocol(IACUC Approval No.LDACU 20190820-01)on August 23,2019 for animal management and use.

Effects of Biliary Tract Pressure on Dynamics of the Oddi's Sphincter and its Nerve Mechanism

In order to explore the effect of binary tract pressure on Oddi's sphincter and the mechanism of development of high pressure of binary tract during acute obstructive and suppurative cholangitis (AOSC), house rabbits were used to establish model of high binary pressure in acute binary duct caecus. It was observed that when the pressure of the acute binary tract was increased to 8 kpa,the electric activity of Oddi's sphincter was obviously enhanced, the pressure of Oddices sphincter increased remarkably (P <0. 05), and even constant spasm appeared with accompanying increase of discharge frequency of the right greater splanchnic nerves (P <0. 05) and progressive decrease of mean arterial pressure.However, when lidocaine of 0. 6 % was used to block the right celiac plexus, no above-mentioned reaction happened when the binary tract pressure was increased again. The results indicated that the acute binary tract obstruction might induce the contraction or spasm of Oddi's sphincter and bring about a vicious cycle. Its mechanism is related to splanchnic nerves reflection and it is one of important factors in the development of AOSC course.

Generation and Shaping of Soliton-Like Pulses along Resonant Tunneling Diodes NMOS Varactors Lattice

The characteristics of N-type accumulation-mode MOS (NMOS) varactors line periodically loaded with resonant tunneling diodes (RTDs) are used for soliton-like pulses generation and shaping. The problem of wide pulse breaking up into multiple pulses rather than a single is solved. Applying perturbative analysis, we show that the dynamics of the nonlinear transmission line (NLTL) is reduced to expanded Korteweg-de Vries (KdV) equation. Moreover, numerical integration of nonlinear differential and difference equations that result from the mathematical analysis of the line is discussed. As results, NLTL can simultaneously sharpen both leading and trailing of pulse edges and one could obtain a rising and sharpening step pulse.

Flux emergence in the solar active region NOAA 11158: the evolution of net current

We present a detailed investigation of the evolution of observed net vertical current using a time series of vector magnetograms of the active region （AR） NOAA 11158 obtained from the Helioseismic and Magnetic Imager. We also discuss the relation of net current to the observed eruptive events. The AR evolved from the βγ to βγδ3 configuration over a period of six days. The AR had two sub-regions of activity with opposite chirality： one dominated by sunspot rotation producing a strong CME, and the other showing large shear motions producing a strong flare. The net current in each polarity over the CME producing sub-region increased to a maximum and then decreased when the sunspots were separated. The time profile of net current in this sub-region followed the time profile of the rotation rate of the south-polarity sunspot in the same sub-region. The net current in the flaring sub-region showed a sudden increase at the time of the strong flare and remained unchanged until the end of the observation, while the sunspots maintained their close proximity. The systematic evo- lution of the observed net current is seen to follow the time evolution of total length of strongly sheared polarity inversion lines in both of the sub-regions. The observed photospheric net current could be explained as an inevitable product of the emergence of a twisted flux rope, from a higher pressure confinement below the photosphere into the lower pressure environment of the photosphere.

Living mycelium composites discern weights via patterns of electrical activity

Fungal construction materials-substrates colonised by mycelium-are getting increased recog-nition as viable ecologically friendly alternatives to conventional building materials.A function-ality of the constructions made from fungal materials would be enriched if blocks with living mycelium,known for their ability to respond to chemical,optical and tactile stimuli,were in-serted.We investigated how large blocks of substrates colonised with mycelium of Ganoderma resinaceum responded to stimulation with heavy weights.We analysed details of the electrical re-sponses to the stimulation with weights and show that ON and OFF stimuli can be discriminated by the living mycelium composites and that a habituation to the stimulation occurs.Novelty of the results cast in the reporting on changes in electrical spiking activity of mycelium bound composites in response to a heavy loads.

Smart bioadhesives for wound healing and closure

The high demand for rapid wound healing has spurred the development of multifunctional and smart bioadhesives with strong bioadhesion,antibacterial effect,real-time sensing,wireless communication,and on-demand treatment capabilities.Bioadhesives with bio-inspired structures and chemicals have shown unprecedented adhesion strengths,as well as tunable optical,electrical,and bio-dissolvable properties.Accelerated wound healing has been achieved via directly released antibacterial and growth factors,material or drug-induced host immune responses,and delivery of curative cells.Most recently,the integration of biosensing and treatment modules with wireless units in a closed-loop system yielded smart bioadhesives,allowing real-time sensing of the physiological conditions(e.g.,pH,temperature,uric acid,glucose,and cytokine)with iterative feedback for drastically enhanced,stage-specific wound healing by triggering drug delivery and treatment to avoid infection or prolonged inflammation.Despite rapid advances in the burgeoning field,challenges still exist in the design and fabrication of integrated systems,particularly for chronic wounds,presenting significant opportunities for the future development of next-generation smart materials and systems.

Effects of Propofol on Respiratory Drive and Patient-ventilator Synchrony during Pressure Support Ventilation in Postoperative Patients： A Prospective Study

Background： Propofol is increasingly nsed during partial support mechanical ventilation such as pressure support ventilation （PSV） in postoperative patients. However breathing pattern, respiratory drive, and patient-ventilator synchrony are affected by the sedative used and the sedation depth. The present study aimed to evaluate the physiologic effects of varying depths ofpropofbl sedation oll respiratory drive and patient-ventilator synchrony during PSV in postoperative patients. Methods： Eight postoperative patients receiving PSV for 〈24 h were enrolled. Propofol was administered to achieve and maintain a Ramsay score of 4, and the inspiratory pressure support was titrated to obtain a tidal volume （VT） of 6-8 ml/kg. Then, tile propolbl dose was reduced to achieve and maintain a Ramsay score of 3 and then 2. At each Ramsay level, the patient underwent 30-rain trials of PSV. We measured the electrical activity of the diaphragm, flow, airway presstlre, neuro-ventilatory efficiency （NVE）, and patient-ventilator synchrony. Results： Increasing the depth of sedation reduced the peak and mean electrical activity of the diaphragm, which suggested a decrease in respiratory drive, while VT remained unchanged. The NVE increased with an increase in the depth of sedation. Minute ventilation and inspiratory duty cycle decreased with an increase in the depth of sedation, but this only achieved statistical significance between Ramsay 2 and both Ramsay 4 and 3 （P 〈 0.05）. The ineffective triggering index increased with increasing sedation depth （9.5 -4- 4.0%, 6.7 - 2.0%, and 4.2-2.1% for Ramsay 4, 3, and 2, respectively） and achieved statistical significance between each pair of depth of sedation （P 〈 0.05）. The depth of sedation did not affect gas exchange. Conclusions： Propofol inhibits respiratory drive and deteriorates patient-ventilator synchrony to tile extent that varies with tile depth of sedation. Propolbl has less effect on breathing pattern and has no effect on VT and gas exchange in postoperative patients with PSV.

Analytic estimation and numerical modeling of actively cooled thermal protection systems with nickel alloys

Actively cooled thermal protection system has great influence on the engine of a hypersonic vehicle, and it is significant to obtain the thermal and stress distribution in the system. So an analytic estimation and numerical modeling are performed in this paper to investigate the behavior of an actively cooled thermal protection system. The analytic estimation is based on the electric analogy method and finite element analysis（FEA） is applied to the numerical simulation. Temperature and stress distributions are obtained for the actively cooled channel walls with three kinds of nickel alloys with or with no thermal barrier coating（TBC）. The temperature of the channel wall with coating has no obvious difference from the one with no coating, but the stress with coating on the channel wall is much smaller than that with no coating. Inconel X-750 has the best characteristics among the three Ni-based materials due to its higher thermal conductivity, lower elasticity module and greater allowable stress. Analytic estimation and numerical modeling results are compared with each other and a reasonable agreement is obtained.

Band gap engineered polymeric-inorganic nanocomposite catalysts:Synthesis, isothermal stability, photocatalytic activity and photovoltaic performance

Polymeric-inorganic nanocomposite catalysts were synthesized by facile one-pot chemical polymerization of pyrrole in the presence of titanium dioxide nanoparticles. The electrical, optical, photovoltaic performance of dye sensitized solar cell（DSSC） and visible light driven photocatalytic activities of the nanocomposite were investigated. The prepared nanocomposite displays excellent photo-activity, attaining 100% degradation of methyl orange dye in 60 min under visible light source while 55% for pure TiO_2 under similar experimental conditions. The photovoltaic performance of the polypyrrole-titanium dioxide（PPy-TiO_2） nanocomposite has a 51.4% improvement with a photo-conversion efficiency of 8.07% as compared to pure TiO_2 based DSSC. By comparing the physical mixture of the PPy-TiO_2 nanocomposite and pristine TiO_2, the enhanced activity of the PPy-TiO_2 nanocomposite can be attributed to the reduced charge transfer resistance, outstanding electrical conductance of the PPy, the nano-sized structure of TiO_2 and their synergetic effect. Furthermore, the PPy-TiO_2 nanocomposite shows excellent electrical conductivity and isothermal stability under ambient conditions below 110？C.

Structured PDMS Chambers for Enhanced Human Neuronal Cell Activity on MEA Platforms

Structured poly（dimethylsiloxane） （PDMS） chambers were designed and fabricated to enhance the signaling of human Embryonic Stem Cell （hESC） - derived neuronal networks on Microelectrode Array （MEA） platforms. The structured PDMS chambers enable cell seeding on restricted areas and thus, reduce the amount of needed coating materials and cells. In addition, the neuronal cells formed spontaneously active networks faster in the structured PDMS chambers than that in control chambers. In the PDMS chambers, the neuronal networks were more active and able to develop their signaling into organized signal trains faster than control cultures. The PDMS chamber design enables much more repeatable analysis and rapid growth of functional neuronal network in vitro. Moreover, due to its easy and cheap fabrication process, new configurations can be easily fabricated based on investigator requirements.