In addition to the structural genes of the coronavirus genome, S, E, M, and N, there are several additional genes called "group-specific or accessory genes". Their gene products are designated as "accessory proteins", as reports to date make it clear that these proteins are not essential for virus replication in vitro. Nevertheless, many of these genes are still maintained in the virus genome under selective pressure, suggesting that they might play a very important role in the survival of the virus in the natural environment of the infected host. This review will summarize the research progress in the functions of coronavirus accessory genes.
Animals ; Coronavirus ; genetics ; metabolism ; Coronavirus Infections ; virology ; Humans ; Open Reading Frames ; Viral Proteins ; metabolism

Objective To identify the subcellular location of S AR S-CoV N protein in mammalian cells. Methods The gene fraction of SARS-CoV was cloned into the PGEFP-C1 plasmid to construct expression vecto r PGEFP-C1/N. The subcellular location of N in A549 and VeroE6 cells was observ ed under fluorescence microscope with the aid of transient transfection techniqu e. The expression of the fusion protein (GFP-N) was detected by Western blot. Results The PGEFP-C1/N was constructed. N protein was localiz ed in the cytoplasm of transfected cells and detected by Western blot. C onclusion N protein was localized in the cytoplasm of mammalian cells.

RhoA, a small GTPase, is involved in a wide array of cellular functions in the central nervous system, such as cell motility, cytoskeleton rearrangement, transcriptional regulation, phagocytosis and cell growth. It is not known how spinal cord injury (SCI) affects the expression of RhoA in different nerve cells. In the present study, we investigated the changes of RhoA expression in remote areas of the injury at the 3rd, 7th and 30th day after SCI, which was established by T10 contusion method. Moreover, we examine its expression profile in neurons, astrocytes and microglia. RhoA was found to be weakly expressed in these nerve cells in normal spinal cord. Western blotting showed that, after SCI, the total RhoA expression was up-regulated, and the RhoA expression was increased and peaked at the 7th day. Double immunostaining revealed specific and temporal expression patterns of RhoA in different nerve cells. The expression of RhoA in neurons started to increase at day 3, peaked at day 7 and then decreased slightly at day 30. Expression of RhoA in astrocytes increased moderately after SCI and peaked at day 7. There was no obvious change in RhoA expression in microglia after SCI in remote areas. This study demonstrated that, after SCI, RhoA expression exhibited different patterns with different nerve cells of spinal cord. RhoA expression patterns also changed with time after SCI, and among different nerve cells in the injured spinal cord. These findings can help us better understand the roles of RhoA in SCI.

BACKGROUND:It is wel-known that mechanical stimulation could promote fracture healing. However, what kind of mechanical stimulation induced by treadmil exercise can increase the bone conductibility of bone material and promote the healing of bone defect is stil unclear.
OBJECTIVE:To evaluate the influence of indirect mechanical stimulation produced by treadmil exercise on bone defect healing and osteogenesis of bone materials.
METHODS:Sprague-Dawley rats at 12 weeks old were used in this study to establish a bone defect of 3 mm in diameter and height at the left distal femur. Afterwards, calcium sulphate scaffolds were implanted into the defects. The rats were divided into treadmil exercise group and control group. Treadmil exercise was began at 1 week postoperatively, 10 m/min, 45 minutes per day, 5 days per week, for 3 weeks. Control group did not receive any exercise. Micro-computed tomography was used to determine bone formation in the bone defects at 1, 2, 3, and 4 weeks after surgery. The sections of left distal femur were subject to hematoxylin-eosin staining, the new bone formation and degradation of bone materials in the bone defects were observed.
RESULTS AND CONCLUSION:Micro-CT analysis showed that, a smal amount of new bone formed in both treadmil exercise group and control group at 1 week after surgery. In treadmil exercise group, new bone formation was significantly higher than the control group at 2, 3, 4 weeks (P<0.05). At 4 weeks, histological results also confirmed the difference of new bone formation in bone defect between treadmil exercise group and control group. In addition, bone mineral density of treadmil exercise group was higher than that of control group at 2, 3, 4 weeks, but no significant difference was found (P>0.05). The results suggest that moderate treadmil exercise could promote bone defect healing and enhance osteoconductivity of bone substitute.

Objective To silence the expression of tissue factor(TF) gene of human umbilical vein endothelial cell(HUVECs) of the newborns with placental abruption(PA) and normal newborns.Methods There were two groups in the experiment,normal group and PA group.Three different treatments were established in each group:(1) the blank; (2) the false-intervention ; (3) the TF gene silencing.There were three samples in each treatments.After these treatments,the changes of mRNA expression of the HUVECs were observed before and aftcr thc gene silencing and the changes of the immunofluorescence of the TF protein level.Results After amplificated,plasmid DNA were sequenced to show that the pENTRTM/U6-TF-shRNA was the positive clone.After the transfected,the levels of the mRNA of TF decreased from 0.657 ± 0.097 to 0.220 ± 0.030 and 1.323 ± 0.323 to 0.207 ± 0.150 in the normal and PA group respectively.Compared with the normal group,there were significant differences for the levels of TF mRNA in PA group with the blank,(1.323 ± 0.323 vs 0.657 ± 0.097,P =0.023) and the same result for the second management (1.057 ±0.178 vs 0.540 ± 0.079,P =0.01).But there was no significant difference between the normal and PA group after RNA interference gene silencing (0.220 ± 0.030 vs 0.207 ± 0.150,P ＞ 0.05).Meanwhile,there were significant differences among the three managements in the themselves groups of normal and pathological ones(F =19.30,P =0.002 ;F =27.66,P =0.001).Conclusion The vectors are transfected into HUVECs and play the biological function.And they silence the expression of TF mRNA.PENTRTM/U6-TF-shRNA could inhibit the expression of TF mRNA of HUVECs in the PA newborn.

Objective To establish an animal model of high-iodine and low-protein in Wistar rats,and to observe the effect of combined excess-iodine and low-protein diet on growth,metabolism and morphological changes in thyroid.Methods According to body weight[(110 ± 10)g] and sex(half male and half female),one hundred and ninety-two Wistar rats,1 month after weaning,were randomly divided into ① normal iodine control group (NI),② 10-fold excess-iodine group (10HI),③ 50-fold excess-iodine group (50HI),④ 100-fold excess-iodine group (100HI),⑤ low-protein control group (LC),⑥ low-protein and l 0-fold excess-iodine group (L10HI),⑦low-protein and 50-fold excess-iodine group (L50HI),⑧ low-protein and 100-fold excess-iodine group(L100HI).Twenty-four rats were in each group,with the experimental period of 6 months.The iodine content of NI and LC groups was 4.65 μg/d; 10HI,50HI and 100HI groups were 46.50,232.50 and 465.00 μg/d,respectively.The animal's body weight,water and feed consumption were recorded weekly.At the end of 60,120,180 days,urine and blood samples were collected from eight rats in each group.Urinary iodine was tested by arseni cerium catalytic spectrophotometry; serum iodine was tested by the method of chloric acid.Histological change of the thyroid gland was observed by transmission electron microscopy and hematoxylin-eosin (HE) staining at the end of 6 months; apoptosis of thyroid was tested by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) method.Results At the end of 4,8,16,18,22 and 24 weeks,the differences of body mass of rats among groups were statistically significant(F =4.26,3.75,4.98,4.09,3.28,3.95,all P ＜ 0.05).At the end of 60,120,180 days,the differences of iodine concentration in urine and blood among groups were statistically significantly (H =5.37,6.03,all P ＜ 0.05).Light microscopy showed that thyroid follicular epithelial cells became flattened,and follicles became distended with colloid following increasing of iodine concentration.Electron microscopy showed increased glial vesicles,condensation of nuclear chromatin,karyopyknosis,and karyolysis with increasing of iodine concentration.The differences of apoptotic indexes among groups were statistically significant (F =4.59,P ＜ 0.01).The apoptotic indexes of L50HI and L100HI groups [(21.50 ± 5.20)‰,(26.70 ± 6.40)‰] were higher than those of 50HI and 100HI groups [(11.20 ± 4.30)‰,(19.40 ± 4.80)‰,P ＜ 0.01 or ＜ 0.05].Conclusion Excessiodine and low-protein can cause growth retardation,abnormal iodine metabolism,and thyroid follicular epithelium damage in Wistar rats.

Adolescent ; Child ; Child, Preschool ; Chronic Disease ; Colonoscopy ; methods ; Diarrhea ; diagnosis ; pathology ; Female ; Humans ; Infant ; Infant, Newborn ; Male

AIM: To study the protection of extract of Radix Atragali composite against acute hepatic injury. METHODS: Fed with the extract of Radix Atragali composite, m ice were injected with D-galactosamine intraperitoneally (800 mg/kg) and rats were i njected with carbon tetrachloride hypodermically (5 mL/kg) to induce acute hepat ic injury on the 8th day. ALT, AST and bilirubin in serum were examined. Patholo gical changes of liver tissue were observed. RESULTS: Compared with model group, activities of ALT and AST, c oncentrations of bilirubin were markedly decreased and pathological scores also showed that degeneration and necrosis of hepatic cell were lighter in the the ex tract of Radix Atragali composite treatment group. CONCLUSION: The extract of Radix Atragali composite attenuat es hepatic injury induced by D-galactosamine or carbon tetrachloride.

Bridged-Ring Compounds ; poisoning ; Female ; Humans ; Middle Aged ; Occupational Exposure ; Rodenticides ; poisoning

Adolescent ; Anal Canal ; physiopathology ; Child ; Constipation ; physiopathology ; Female ; Gastrointestinal Motility ; physiology ; Humans ; Male ; Rectum ; physiopathology