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In May 2022, cases of monkeypox were reported in non-monkeypox endemic countries such as Europe and the United States. As of 26 May, a cumulative total of 257 laboratory-confirmed cases and approximately 120 suspected cases had been reported to WHO from non-monkeypox endemic countries. This event immediately caused great concern and alarm to the WHO and national virologists. This paper aims to summarize the epidemiological and clinical features of previous monkeypox virus infections and the current local outbreaks in non-monkeypox endemic countries and propose countermeasures to control the current localized infections in non-monkeypox endemic areas as soon as possible. We reviewed the literature and websites related to monkeypox. We searched Google Scholar, PubMed, Web of Science, Embase, and African Journals Online using the medical subject terms "monkeypox", "monkeypox virus", "monkeypox outbreak", "non-monkeypox endemic areas", "clinical features", "epidemiology", "transmission", and "infection". We found that monkeypox is a zoonotic disease of forest animals that has occurred mainly in West and Central Africa since the first case was reported in the Congo in 1970, with occasional cases spreading to countries such as the United States and Europe. It is common among students, housekeepers, hunters, farmers and housewives. It is more common in males than females, occurs below middle age, and is more common in children under 10. The incubation period is 5 to 21 days, and the rash usually appears within 1 to 3 days after the onset of fever. Clinical manifestations include fever, rash, swollen lymph nodes, headache, muscle pain and unusual weakness. Most patients have mild symptoms that last from 2 to 4 weeks. The source of the sudden outbreak in Europe and the United States is currently unknown and occurs mostly in homosexuals who have sex with men (MSM). Outbreaks of monkeypox virus infection in non-monkeypox endemic areas have received widespread attention and focus. We believe that a scientific response to the transmission route of monkeypox virus and, where necessary, vaccination of high-risk groups against the monkeypox smallpox will control infection in non-monkeypox endemic areas.

A novel analyzed beam-forming (ABF) network is proposed in this paper. It features three attractive advantages of wide bandwidth, compact physical size and stable beam direction. The simulated results indicate that the presented ABF network can achieve triple-band and produce two-lobed beams at ±2.81° and ±8.43°. It is also worth to mention that the overall size is only 320 mm × 120 mm × 9 mm. Moreover, the measured results agree well with the theoretical ones. These results are quite helpful in designing beam-forming antenna arrays.

The relationship between geodesic acoustic modes (GAMs) and tearing modes (TMs), or locked modes (LMs), have been investigated in EAST. Firstly, multi-branch electromagnetic GAMs are observed synchronously after the excitation of TMs. Broadened radial coverage is observed for these branches, and these frequencies can be described by the dispersion relation of GAM. Secondly, multi-branch electromagnetic GAMs are generated after the excitation of LMs. The toroidal asymmetric structure of GAMs is excited due to the existence of 3D intrinsic error fields, and the radial distribution of those branches is altered accordingly. Four branches of electromagnetic GAMs are observed in the region that is closer to the ‘X’-point of the locked magnetic islands, which should be merged into two branches for the region that is closer to the ‘O’-point, as confirmed by XUV array measurement. Thirdly, a similar phenomenon is reproduced by the modulation of resonant magnetic perturbation (RMP). The frequency of GAM increases with the current of the RMP coils, and multi-branches of similar modes are generated when the current achieves I R M P = 2.5 kA, where the electrostatic and electromagnetic components are altered accordingly. The features of those branches are modulated by the rotation of the RMP. Therefore, the structures of the pair of GAMs can be different, which should be influenced by the different magnetic topological structure.

GLI2 is a key mediator of the sonic hedgehog (Shh) signaling pathway and plays an important role in neural tube development during vertebrate embryogenesis; however, the role of gli2 in human folate-related neural tube defects remains unclear. In this study, we compared methylation status and polymorphisms of gli2 between spina bifida patients and a control group to explore the underlying mechanisms related to folate deficiency in spina bifida. No single nucleotide polymorphism was found to be significantly different between the two groups, although gli2 methylation levels were significantly increased in spina bifida samples, accompanied by aberrant GLI2 expression. Moreover, a prominent negative correlation was found between the folate level in brain tissue and the gli2 methylation status (r = -0.41, P = 0.014), and gli2 hypermethylation increased the risk of spina bifida with an odds ratio of 12.45 (95 % confidence interval: 2.71-57.22, P = 0.001). In addition, we established a cell model to illustrate the effect of gli2 expression and the accessibility of chromatin affected by methylation. High gli2 and gli1 mRNA expression was detected in 5-Aza-treated cells, while gli2 hypermethylation resulted in chromatin inaccessibility and a reduced association with nuclear proteins containing transcriptional factors. More meaningful to the pathway, the effect gene of the Shh pathway, gli1, was found to have a reduced level of expression along with a decreased expression of gli2 in our cell model. Aberrant high methylation resulted in the low expression of gli2 in spina bifida, which was affected by the change in chromatin status and the capacity of transcription factor binding.

The associated effects of polarization strength, polarization rate, and dielectric loss on ER performance ware studied by means of the correlation of rheological properties of carbon-doped TiO 2 ER fluids with experimental results of flow-modified permittivity (FMP). We prepared ER fluids with carbon-doped TiO 2 powders of different conductivity via controlling carbonization temperature and organic contents. The experiments present the optimum organic contents of 4.6% to 9.2% and the optimum carbonization temperature of around 673 K for the better ER activity. The role of conductivity in ER performance is testified. FMP measurements of fluids were performed under weak and strong exciting fields respectively. Under weak exciting field, FMP effects are hardly detectable; while under high exciting field, FMP effects become significant which reflect ER particle configurations, particle orientations, and limited dielectric response time in the combined electric and shear fields. The shear field strength, exciting field strength and frequency are the three main factors influencing the FMP effects. The FMP data can be modeled and qualitatively explained by introducing two characteristic shear rates of D c 1 and D c 2, J = J 0+ J 1 exp (- D / D c 1)+ J 2 exp (- D / D c 2) with D being shear rate.

A simplified model is considered to describe the resistive transport and diffusion of charge carriers within or around an ER active particle under influence of AC electric field and temperature. The effective polarization strength, dielectric constant and dielectric loss of the particle are derived from this model. Considered the effects of shear field, the criteria for ER activity are presented as ωτ >10-4, 12 and ωτ d/λ3s-1. The criteria determine the lower and upper limits of the polarization rate and dielectric loss of ER particles. The criteria are testified by the following experimental results. First, the measured lower limit of diatomite particle conductivity is 7.3×10-8S/m. Second, the shear stresses at the shear rates from 9.9 to 100 s -1 at 1kV/mm field start to rise with temperature from 25°C. Third, with decreasing shear rate or/and increasing electric field strength, the peaks of shear stress shift down the lower temperatures.

Under the consideration of the role that energy transfer and dissipation play in ER effect, an improved theory frame for ER effects, polarization-dissipation-structure-rheology, is suggested. The theory frame is substantiated by the basic physical laws and certain critical experimental facts. The dielectric response of a diatomite ER fluid to temperature is measured in the temperature range of 140 K to 400 K. By comparison of the DC conductivity with the AC effective conductivity of the sample, we found that the AC dielectric loss consists of two parts. One part comes from the DC conductivity, the other from the response of the bound charges in scope of particle to AC field. It is suggested that the response of bound charges is very important to ER effects. Besides, the effect of temperature on shear stress is measured, and interpreted based on the dielectric measurements. The source of two loss peaks in the curve of the dielectric loss versus temperature is not clear.

The helicity of stable single helical carbon chains and iodine chains inside single-walled carbon nanotubes (SWCNTs) is studied by calculating the systematic van der Waals interaction energy. The results show that the optimal helical radius increases linearly with increasing tube radius, which produces a constant separation between the chain structure and the tube wall. The helical angle exhibits a ladder-like decrease with increasing tube radius, indicating that a large tube can produce a small helicity in the helical structures.

The relations between the rheological and electrical properties of NaY zeolite electrorheological fluid and its solid phase are studied. It is found that there exist complex relations between its electrical and rheological properties. The temperature spectra of dielectric properties of the fluid under high AC electric field are strongly field strength dependent. The relation between the DC conductivity of the fluid and the exciting electric field is experimentally presented as log σ= A + BE 1/2, where A is a strong function, but B, a very weak function of temperature. The shear stress of the fluid under a fixed electric field and temperature decreases with shear rate. A relaxation time for the adsorbed charges is estimated to be about 0.3 to 6.6 s in the temperature range from 280 to 380 K. The relaxation time qualitatively corresponds to the shear rate at which the shear stress begins to drop. The time dependent leaking current of the ER fluids under DC electric field is also measured. The conductivity increase is mainly caused by the structure evolution of particles. The experimental results can be explained with the calculations of Davis (J. Appl. Phys.81 (1997) pp. 1985–1991) and Martin (J. Chem. Phys.110 (1999) pp. 4854–4866). It is predicted that the NaY zeolite ER fluid strength would get degraded slowly.

The non-linear dielectric property of the electrorheological (ER) fluids under high AC electric field still lacks detailed investigation compared with other studies on ER fluids. In its physical principle, ER effect is the result of interaction of high electric field with chemical configurations and liquid environment of solid particles. In the investigation of applications, the response time, power dissipation, strength and stability of ER fluids are closely related to the dielectric properties of the fluids. The study of non-linear dielectric properties of the ER fluids can be a key to reveal their peculiar rheological properties, and would be hopeful to provide information for the research of ER materials.

Composites of fibronectin/mineral and osteogenic growth peptide/mineral were synthesized on calcium phosphate coated substrates immersed in Dulbecco's phosphate-buffered saline solution containing biomolecules. The kinetics of coprecipitation for two biomolecules was similar, and the biomolecules participated in the formation of the crystal latticework and influenced the mineral structure and composition.

Levo-praziquantel is the left isomer of racemic praziquantel. Animal experiments showed that it is an active component of schistosomicidal activity, while dextro-praziquantel is almost ineffective. Clinical trials in three endemic areas of Schistosomiasis japonica indicated that the therapeutic efficacy of levo-praziquantel is superior to racemic praziquantel. Pharmacokinetic and pharmacodynamic activities of the stereoselectivity of praziquantel isomers (enantiomers) are discussed.

In this paper, the effect of Schistosoma japonicum infection on liver drug-metabolizing enzymes of mice was studied. The prolongation of hypnosis duration of sodium pentobarbital in vivo and the inhibition of liver aniline hydroxylase (AH), aminopyrine N-demethylase (APD) as well as cytochrome P-450 (Cyt P-450) in vitro were observed in mice infected with 20, 40 and 60 cercariae of S. japonicum after 6 weeks. Meanwhile, with 30 cercariae infection, no significant inhibition of the activity of AH, APD and Cyt P-450 was observed in mice 4 weeks after infection, but significant inhibition of these enzymes was shown by 8 weeks. As compared with control, the activity of AH, APD and Cyt P-450 decreased to 32.6%, 13.7% and 7.7% at 8 weeks. The results indicate that infection of S. japonicum can inhibit the liver drug-metabolizing capacity of mice, and the degree of inhibition depends on the infectivity and the duration of infection.

The enantiomers of praziquanamine were separated by reversed phase HPLC after derivatization with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosylisothiocyanate (GITC). The determination of the optical purity of praziquanamine was successfully achieved. This method was applied to the determination of the optical purity of d- and l-praziquanamines.

"85012", a new anthelmintic containing amidine synthesized in our laboratory, was experimentally effective against Nippostrongylus braziliensis and Ancylostoma caninum. In acute and subacute toxicity test, it was proved lowly toxic. There was no evidence that the drug induced any damages to main organs and tissues of animals. In order to evaluate its potential mutagenicity and teratogenicity, micronucleus test, bone marrow metaphase analysis, CHL cells chromosomal aberration assay, spermatic aberration test as well as teratogenicity test were performed. No mutagenic and teratogenic effects were observed.

The stereoselective binding of praziquantel (PQT) enantiomers to plasma proteins was studied by equilibrium dialysis. The binding of (+/-)-PQT and its enantiomers to bovine serum albumin (BSA) and rabbit plasma was unsaturable when initial drug concentrations from 1 to 32 mumol/L were used. The binding capacity (nK) of (+/-)-PQT to BSA (1.47 or 5.88 x 10(-4) mol/L) was greater than that of (-)-PQT with a (+)-/(-)-PQT ratio of 1.25 or 1.26, respectively. However, the preferential binding of (-)-PQT to rabbit plasma was found to be 73.7 +/- 4.4% for (-)-isomer and 58.3 +/- 10.1% for (+)-isomer (n = 8, P less than 0.05). The binding of (+)- and (-)-PQT to human plasma was 81.9 +/- 4.2% and 83.2 +/- 6.9% (n = 10, P greater than 0.05) respectively, which seems to be not stereoselective. These results indicate that there are species differences in the stereoselective binding of PQT enantiomers to plasma proteins.

Praziquantel (PQT) is a racemic mixture. Intragastric gavage of (-)-, (+)- and (+/-)-PQT 100 mg/kg were used to study the liver first pass effects in rabbits. HPLC was used to determine the concentration of each compound in the portal and systemic circulation, and in the bile within 4h. The results showed that all drugs were absorbed rapidly from the gut into the portal vein. The serum concentration in the portal vein were similar. However, over 90% of PQT and its enantiomers were extracted in the first passage through the liver. Intrinsic metabolic clearances of the liver of (-)-, (+)- and (+/-)-PQT were 50.3, 174.4 and 52.6 L/h, respectively. The serum concentrations of the three drugs markedly decreased in the systemic circulation, especially that of (+)-PQT. The AUC of (+)-PQT was apparently lower than that of (-)- or (+/-)-PQT. From these results, it is assumed that the first pass effects of PQT and its enantiomers in the liver are pronounced and most likely stereoselective. Also, unchanged PQT and its enantiomers were found in the bile of the rabbits.