Search

Nanomaterials have received increasing attentions owing to their potential hazards to the environment and human health; however, the multi-generational toxicity of graphene oxide under consecutive multi-generational exposure scenario still remains unclear. In the present study, Caenorhabditis elegans as an in vivo model organism was employed to explore the multi-generational toxicity effects of graphene oxide and the underlying mechanisms. Endpoints including development and lifespan, locomotion behaviors, defecation cycle, brood sizes, and oxidative response were evaluated in the parental generation and subsequent five filial generations. After continuous exposure for several generations, worms grew smaller and lived shorter. The locomotion behaviors were reduced across the filial generations and these reduced trends were following the impairments of locomotion-related neurons. In addition, the extended defecation cycles from the third filial generation were in consistency with the relative size reduction of the defecation related neuron. Simultaneously, the fertility function of the nematode was impaired under consecutive exposure as reduced brood sizes and oocytes numbers, increased apoptosis of germline, and aberrant expression of reproductive related genes ced-3, ced-4, ced-9, egl-1 and ced-13 were detected in exposed worms. Furthermore, the antioxidant enzyme, SOD-3 was significantly increased in the parent and filial generations. Thus, continuous multi-generational exposure to graphene oxide caused damage to the neuron development and the reproductive system in nematodes. These toxic effects could be reflected by indicators such as growth inhibition, shortened lifespan, and locomotion behavior impairment and induced oxidative response.

To observe the effect of electroacupuncture (EA) stimulation of Heart and Lung meridians on the expression of hyperpolarization-activated cyclic nucleotide gated potassium channel 2 (HCN 2) mRNA and protein in the myocar-dium of the left ventricle in acute myocardial ischemia (AMI) rats, so as to underlying its mechanism in improving ischemic myocardial injury.A total of 120 male SD rats were randomly divided into normal control, model, EA-Heart Meridian (HT) and EA-Lung Meridian (LU) groups (After AMI, both HCN 2 mRNA and protein expression levels in the model group were significantly decreased in comparison with the normal control group (Both EA stimulation of Heart Meridian and Lung Meridian can improve the expression of HCN 2 mRNA and protein in the myocardium in AMI rats, which existing a delayed effect and meridian specificity.

To study the effect of moxa-smoke inhaling on the respiratory system, so as to provide experimental data and theoretical basis for evaluating the safety of moxa-smoke inhaling during moxibustion treatment.A total of 48 SD rats were randomized into control, low, medium and high moxa-smoke-concentration groups (After 100 days' moxa-smoke inhaling, the contents of TNF-α in the plasma, BALF and lung tissues and IL-1 β in the lung tissue of the low, medium and high concentration moxa-smoke groups, and IL-1 β in the plasma and BALF of the medium and high concentration groups were significantly increased relevant to the control group (Long term inhalation of high concentration of moxa-smoke may lead to inflammatory injury in the lung and bronchial tissues but has no significant effect on the respiratory function in rats. Nevertheless, a good air-ventilation during moxibustion in a treatment room is necessary.

To obtain hydrolysates with high degree of hydrolysis (DH) and scavenging radical activity, tilapia skin gelatin (TSG) was hydrolyzed by properase E and multifect neutral. The optimum hydrolysis condition of each enzyme was determined using the orthogonal experiment, and double-enzyme hydrolysis was further applied. The results showed the tilapia skin gelatin hydrolysate (TSGH) obtained by progressive hydrolysis using multifect neutral and properase E had the highest DH and hydroxyl radical scavenging activity. The IC(50) values of TSGH on scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical (·O(2)) and hydroxyl radical (·OH) activities were also determined. TSGH was further purified using gel filtration chromatography, ion exchange chromatography, and RP-HPLC. The peptides were identified using nano-LC-ESI mass spectrometry. Finally, two antioxidant peptides were identified and the amino acid sequences were Glu-Gly-Leu (317.33 Da) and Tyr-Gly-Asp-Glu-Tyr (645.21 Da), respectively. The IC(50) values of two peptides on hydroxyl radical scavenging activities were 4.61 μg mL(-1)and 6.45 μg mL(-1), respectively. Therefore, the results demonstrated that the hydrolysates of TSG prepared by multifect neutral and properase E could serve as a source of peptides with high antioxidant activity. It provided a scientific basis for the preparation of antioxidant peptides.

Comparing the difference of virulence between the strain CGRn5310 (HTNV) and the strain HR54 (SEOV) isolated both from Rattus norvegicus.Suckling mice were used to compare the difference of virulence between the two strains. Hantavirus antigens were detected in brain and lung tissues collected from the infected mice.Compared with the control group, all infected mice grew slowly. Furthermore, the mice inoculated intracerebrally with either CGRn5310 or HR45 appeared ruffled fur, and reduced activity, followed by neurological symptoms, such as paralyses and convulsions. The half lethal dose (LD(50)) of CGRn5310 strain was 10(-6.42), whereas the LD(50) of HR54 strain was 10(-4.51). Hantavirus antigens were identified in brain and lung tissues from the mice infected with the strain CGRn5310 and the strain HR54.LD(50) of the strain CGRn5310 was significantly higher than that of the strain HR54. Our results suggested that the virulence of the spillover hantavirus might only slightly be influenced by the non-reservoir rodents.

To gain further insight into the molecular epidemiology of Hantaan virus (HTNV) in Guizhou, China, rodents were captured in this region in 2004 and 2005. In addition, serum samples were collected from four patients. Ten hantaviruses were isolated successfully in cell culture from four humans, two Apodemus agrarius, three Rattus norvegicus and one Rattus nitidus. The nucleotide sequences for their small (S), medium (M) and partial large (L) segments were determined. Phylogenetic analysis of the S and M segment sequences revealed that all of these isolates belong to the species HTNV, suggesting a spillover of HTNV from A. agrarius to Rattus rats. All available isolates from Guizhou were divided into four distinct groups either in the S segment tree or in the M segment tree. The clustering pattern of these isolates in the S segment tree was not in agreement with that in the M or L segment tree, showing that genetic reassortment between HTNV had occurred naturally. Analysis of the S segment sequences from available HTNV strains indicated that they formed three clades. The first clade, which comprised only viruses from Guizhou, was the outgroup of clades II and III. The viruses in the second clade were found in Guizhou and mainly in the far-east Asian region, including China. However, the viruses in the third clade were found in most areas of China, including Guizhou, in which haemorrhagic fever with renal syndrome (HFRS) is endemic. Our results reveal that the highest genetic diversity of HTNV is in a limited geographical region of Guizhou, and suggest that Guizhou might be a radiation centre of the present form of HTNV.