[Impact of subchronic exposure to low-dose nano-nickel oxide on the reproductive function and offspring of male rats].

OBJECTIVE: To investigate the influence of subchronic exposure to low-dose subchronic nano-nickel oxide (NNO) on the reproductive function of male rats and embryonic development of the pregnant rats. METHODS: Fifty normal healthy male SD rats weighing 180－220 g were randomly divided into five groups of equal number, negative control, 4 mg/ml micro-nickel oxide (MNO), and 0.16, 0.8 and 4 mg/ml NNO, those of the latter four groups exposed to MNO or NNO by non-contact intratracheal instillation once every 3 days for 60 days, and then all mated with normal adult female rats in the ratio of 1∶2. After the female animals were confirmed to be pregnant, the males were sacrificed and the weights of the body, testis and epididymis obtained, followed by calculation of the visceral coefficients, determination of epididymal sperm concentration and viability and the nickel contents in the blood and semen by atomic fluorescence spectrometry. The female rats were killed on the 20th day of gestation for counting of the implanted fertilized eggs and live, dead and resorbed fetuses. RESULTS: After 60 days of exposure, the rats of the NNO groups showed no statistically significant differences from those of the negative control and MNO groups in the weights of the body, testis and epididymis or visceral coefficients. Compared with the negative control group, the animals of the 0.8 and 4 mg/ml NNO groups exhibited markedly decreased sperm concentration (ï¼»9.36 ± 0.98ï¼½ vs ï¼»7.49 ± 1.46ï¼½ and ï¼»6.30 ± 1.36ï¼½ ×106/ml, P < 0.05) and viable sperm (ï¼»85.35 ± 9.16ï¼½% vs ï¼»68.26 ± 16.63ï¼½% and ï¼»65.88 ± 14.68ï¼½ %, P < 0.05), increased morphologically abnormal sperm (ï¼»8.30 ± 2.47ï¼½% vs ï¼»13.99 ± 4.87ï¼½% and ï¼»15.38 ± 8.86ï¼½ %, P < 0.05), and elevated rate of dead and resorbed fetuses (1.18% vs 6.89% and 7.37%, P < 0.05), blood nickel content (ï¼»0.13 ± 0.16ï¼½ vs ï¼»0.52 ± 0.34ï¼½ and ï¼»0.82 ± 0.44ï¼½ mg/L, P < 0.05) and semen nickel content (ï¼»0.08 ± 0.13ï¼½ vs ï¼»0.35 ± 0.23ï¼½ and ï¼»0.63 ± 0.61ï¼½ mg/L, P < 0.05). The nickel level in the semen was correlated significantly with that in the blood (r = 0.912, P <0.01), negatively with the rate of viable sperm (r = －0.879, P <0.01) and positively with the percentage of morphologically abnormal sperm (r = －0.898, P <0.01). CONCLUSIONS: Sixty-day exposure to nano-nickel oxide at 0.8 and 4 mg/ml can produce reproductive toxicity in male rats and result in fetal abnormality in the females, while that at 0.16 mg/ml has no significant toxic effect on the reproductive function of the males.

mir-233 modulates the unfolded protein response in C. elegans during Pseudomonas aeruginosa infection.

The unfolded protein response (UPR), which is activated by perturbations of the endoplasmic reticulum homeostasis, has been shown to play an important role in innate immunity and inflammation. However, little is known about the molecular mechanisms underlying activation of the UPR during immune responses. Using small RNA deep sequencing and reverse genetic analysis, we show that the microRNA mir-233 is required for activation of the UPR in Caenorhabditis elegans exposed to Pseudomonas aeruginosa PA14. P. aeruginosa infection up-regulates the expression of mir-233 in a p38 MAPK-dependent manner. Quantitative proteomic analysis identifies SCA-1, a C. elegans homologue of the sarco/endoplasmic reticulum Ca2+-ATPase, as a target of mir-233. During P. aeruginosa PA14 infection, mir-233 represses the protein levels of SCA-1, which in turn leads to activation of the UPR. Whereas mir-233 mutants are more sensitive to P. aeruginosa infection, knockdown of sca-1 leads to enhanced resistance to the killing by P. aeruginosa. Our study indicates that microRNA-dependent pathways may have an impact on innate immunity by activating the UPR.

Overexpression of microRNA-183 promotes apoptosis of substantia nigra neurons via the inhibition of OSMR in a mouse model of Parkinson's disease.

The present study aimed to investigate the effect of microRNA­183 (miR­183) on substantia nigra neurons by targeting oncostatin M receptor (OSMR) in a mouse model of Parkinson's disease (PD). The positive expression rates of OSMR and the apoptosis of substantia nigra neurons were detected by immunohistochemistry and terminal deoxynucleotidyl transferase­mediated dUTP­biotin nick end­labeling, respectively. Substantia nigra neurons in normal and PD mice were cultured in vitro. The association between miR­183 and OSMR was verified using a dual luciferase reporter gene assay. The expression of miR­183 and the phosphoinositide 3­kinase­Akt signaling pathway­associated genes were detected by reverse transcription­quantitative polymerase chain reaction and western blot analysis, respectively. Cell apoptosis was detected by flow cytometry. OSMR is the target gene of miR­183. The number of OSMR­positive cells and the apoptotic rate of substantia nigra neurons were increased in the PD group. Neurons transfected with miR­183 mimic exhibited elevated expression levels of miR­183, B­cell lymphoma 2 (Bcl­2)­associated X protein (Bax) and caspase­9 and increased apoptotic rate, and reduced expression levels of OSMR, Akt, phosphorylated (p­)Akt, glycogen synthase kinase­3 (GSK­3ß), p­GSK­3ß, Bcl­2, insulin­like growth factor 1 (IGF­1), mammalian target of rapamycin (mTOR) and p­mTOR. The miR­183 inhibitor decreased the expression levels of miR­183, Bax and caspase­9 and the apoptotic rate; however, increased the expression of OSMR, Akt, p­Akt, GSK­3ß, p­GSK­3ß, Bcl­2, IGF­1, mTOR and p­mTOR. The results of the present study provide evidence that the overexpression of miR­183 promotes the apoptosis of substantia nigra neurons by inhibiting the expression of OSMR.

Silencing NUDT21 Attenuates the Mesenchymal Identity of Glioblastoma Cells via the NF-κB Pathway.

The proneural (PN) and mesenchymal (MES) subtypes of glioblastoma multiforme (GBM) are robust and generally consistent with classification schemes. GBMs in the MES subclass are predominantly primary tumors that, compared to PN tumors, exhibit a worse prognosis; thus, understanding the mechanism of MES differentiation may be of great benefit for the treatment of GBM. Nuclear factor kappa B (NF-κB) signaling is critically important in GBM, and activation of NF-κB could induce MES transdifferentiation in GBM, which warrants additional research. NUDT21 is a newly discovered tumor-associated gene according to our current research. The exact roles of NUDT21 in cancer incidence have not been elucidated. Here, we report that NUDT21 expression was upregulated in human glioma tissues and that NUDT21 promoted glioma cell proliferation, likely through the NF-κB signaling pathway. Gene set enrichment analysis, western blotting, and quantitative real-time reverse transcription polymerase chain reaction confirmed that NF-κB inhibitor zeta (NFKBIZ) was a downstream target affected by NUDT21 and that the MES identity genes in glioblastoma cells, CHI3L1 and FN1, were also differentially regulated. Our results suggest that NUDT21 is an upstream regulator of the NF-κB pathway and a potential molecular target for the MES subtype of GBM.

Predicting hospital mortality using APACHE II scores in neurocritically ill patients: a prospective study.

Four versions of Acute Physiology and Chronic Health Evaluation are limited in predicting hospital mortality for neurocritically ill patients. This prospective study aimed to develop and assess the accuracy of a modified APACHE II model in predicting mortality in neurologic intensive care unit (N-ICU). A total of 653 patients entered the study. APACHE II scores on admission, and worst 24-, 48-, and 72-h scores were obtained. Neurologic diagnoses on admission were classified into five categories: cerebral infarction, intracranial hemorrhage, neurologic infection, neuromuscular disease, and other neurologic diseases. We developed a modified APACHE II model based on the variables of the 72-h APACHE II score and disease category using a multivariate logistic regression procedure to estimate probability of death. We assessed the calibration and discrimination of the modified APACHE II model using the Hosmer-Lemeshow goodness-of-fit chi-squared statistic and area under the receiver operating characteristic curve (AU-ROC). The modified APACHE II model had good discrimination (AU-ROC = 0.88) and calibration (Hosmer-Lemeshow statistic: chi (2) = 3.707, P = 0.834). The discrimination of the 72-h APACHE II score for cerebral infarction, intracerebral hemorrhage, and neurologic infection was satisfactory, with AU-ROC of 0.858, 0.863, and 1.000, respectively, but it was poor in discriminating for the categories of other neurologic diseases and neuromuscular disease. The results showed that our modified APACHE II model can accurately predict hospital mortality for patients in N-ICU. It is more applicable to clinical practice than the previous model because of its simplicity and ease of use.