Objective To compare and analyze the occupational exposure limit（OEL）of hexavalent chromium compounds in China and foreign countries. Methods The OEL and background information of hexavalent chromium compounds released by nine official and unofficial organizations in seven countries/regions were collected and sorted. The classification，limit levels， formulation principles and compound characteristics labeling of OEL were compared. Results The OEL values published by nine organizations ranged from 0.000 02 to 0.050 00 mg/m3 . Among them，the limits of seven organizations（including China） did not clearly distinguish the soluble types of hexavalent chromium compounds；the limits of eight organizations（including China）were calculated in terms of chromium；seven organizations（including China）have only developed OEL for long-term exposure. The OEL of hexavalent chromium in China was 0.050 00 mg/m3 which is relatively loose. Its carcinogenicity label was consistent with international standards，its sensitization label was consistent with some countries，and its percutaneous absorption label had not been included in the characteristic labeling of limit values. Conclusion It is suggested that the OEL of hexavalent chromium in China should be revised timely，and the systemic adverse effects caused by percutaneous absorption of hexavalent chromium compounds should be focused on. At the same time，it is recommended to systematically adjust the management concepts and principles of all carcinogens.

Objective To explore the role and their relationship of Ki-67, VEGF and p27 expressed in adult patients with acute leukemia. Methods The expression of Ki-67, VEGF and p27 in bone marrow mononuclear cells (BMMNC) were analyzed by immunocytochemical staining, and their correlations of Ki-67, VEGF and p27 were statistically analyzed. Results The expression of Ki-67(42.48±25.78)% or VEGF (44.89±24.01)% on BMMNC from acute leukemia cells was significantly higher than that in the control (11.40±9.94)% or (16.90±12.54)% (P<0.01). But the expression of p27 (23.65±13.30)% was significantly lower than that in the control (50.23±22.68)% (P<0.01). The expressions of Ki-67 were positively correlated with and VEGF in patients with acute leukemia were positively correlated(r=-0.666, P<0.01), and the expressions of Ki-67 and p27 were negatively correlated with p27 in patients with acute leukemia (r=-0.316, P<0.05).Conclusion The evaluation of expression of Ki-67, VEGF and p27 on acute leukemic cells provides new insights to the pathogenesis is helpful in mechanism and is helpful in the diagnosis of acute leukemia.

This study was aimed to optimize the purification technology for Sambucus williamsii Hance. With the morroniside as a marker, the purification technology for Sambucus williamsii Hance was optimized by different types of macroporous resin. The results showed that the optimum purification technology was that, the extract of less than 1:250 (morroniside:resin) was adsorbed and the AB-8 resin was washed with distilled water, and then the morroni-side was eluted from the macroporous resin with 10% ethanol. And the content of the morroniside was more than 50%. It was concluded that the purification technology was simple, reliable, repeatable and suitable for industrial production.

Objective: To analyze the clinical characteristics of streptococcal toxic shock syndrome (STSS) caused by Streptococcus pyogenes (S. pyogenes) in the third trimester to improve clinical awareness of this disease. Methods: A retrospective study was conducted to analyze the clinical data of two patients with STSS caused by S. pyogenes in Jinan Maternal and Child Health Care Hospital and nine reported cases of healthy pregnant women infected with S. pyogenes at 28-42 gestational weeks with detailed data retrieved from Chinese National Knowledge Infrastructure and PubMed database from January 1997 to December 2018. Results: The two cases admitted to our hospital were both multiparas, with onset in winter and no specific symptoms in early stage. Disseminated intravascular coagulation (DIC) was developed in both cases on admission. In one case, the fetal heart rate was reduced and disappeared soon after admission. The other patient was diagnosed as stillbirth on admission. Both patients died and blood culture revealed infection of group A streptococcus. Nine previous cases were reported in one Chinese and five English articles. No high-risk pregnancy or premature rupture of membranes was reported in these 11 cases. Among the 11 cases, ten were positive for S. pyogenes indicated by blood or tissue culture and one was positive for streptococcal toxin. Ten cases had high fever and three presented with respiratory symptoms in early stage. Abdominal pain and watery diarrhea were common symptoms and all patients developed multiple organ dysfunction and DIC. Cases occurred in winter or spring were more common. Nine women died within 36 h after the onset of fulminant symptoms. Only two survived and hospitalized for 90 d and 25 d, respectively, after emergent cesarean section indicated by reduced fetal heart rate. Unfortunately, both neonates died after birth. For the babies, there were seven intrauterine fetal deaths, one stillbirth and three live births, but only one survived (whose mother developed respiratory cardiac arrest 90 min after delivery). Conclusions STSS caused by S. pyogenes in pregnant women exacerbates rapidly with a high mortality. Early identification of clinical manifestations and rapid progress of the disease are crucial for early diagnosis and treatment, which may help improve maternal and fetal outcomes.

To investigate the role of mitochondria in neuronal apoptosis, ischemia-reperfusion mediated neuronal cell injury model was established by depriving of glucose, serum and oxygen in media. DNA fragmentation, cell viability, cytochrome C releasing, caspase3 activity and mitochondrial transmembrane potential were observed after N2a cells suffered the insults. The results showed that N2a cells in ischemic territory exhibited survival damage, classical cell apoptosis change, DNA ladder and activation of caspase3. Apoptosis-related alterations in mitochondrial functions, including release of cytochrome C and depression of mitochondrial transmembrane potential (deltapsim) were testified in N2a cells after mimic ischemia-reperfusion. Moreover, activation of caspase3 occurred following the release of cytochrome C. However, the inhibitor of caspase3, Ac-DEVD-CHO, couldn't completely rescue N2a cells from apoptosis. Administration of cyclosporine A, an inhibitor of mitochondria permeability transition pore only partly inhibited caspase3 activity and reduced DNA damage. Interestingly, treatment of Z-IETD-FMK, an inhibitor of caspase8 could completely reverse DNA fragmentation, but can't completely inhibit caspase3 activity. It was concluded that there were caspase3 dependent and independent cellular apoptosis pathways in N2a cells suffering ischemia-reperfusion insults. Mitochondria dysfunction may early trigger apoptosis and amplify apoptosis signal.
Animals ; Apoptosis ; physiology ; Caspase 3 ; Caspases ; biosynthesis ; Cytochromes c ; biosynthesis ; Mice ; Mitochondria ; physiology ; Neuroblastoma ; pathology ; Neurons ; pathology ; Reperfusion Injury ; metabolism ; pathology ; Tumor Cells, Cultured

Objective: To investigate the correlation between age-related hearing loss and cognitive impairment. Methods: 201 elderly patients, who were admitted to the Department of Otorhinolaryngology of Peking University People′s Hospital from March 1, 2017 to March 31, 2017, were evaluated with hearing screening and the Montreal Cognitive Assessment Scale. Among them, 101 were female and 100 were male, aged 60-90 years old. Taking the cognitive level as the dependent variable, and taking the age, sex, education, occupation, marital status, residence, and average hearing loss (average hearing threshold of 500, 1 000, 2 000, and 4 000 Hz), as well as the length of conscious hearing loss as the independent variables, the single factor analysis and multivariate linear regression analysis were used to screen the main factors affecting the cognitive level of the elderly. Results: Of the 201 elderly patients, 39 had normal hearing, 65 had mild hearing loss, 80 had moderate hearing loss, 16 had severe hearing loss, and 1 had profound hearing loss. The average degree of hearing loss was the influencing factor of cognitive impairment, and it mainly affected the directional force and abstract ability in the cognitive domains (P<0.05); The age, self-reported hearing loss, years of education, marital status, past ear diseases, and hypertension were relatively independent factors that affected the cognitive level(P<0.05). Conclusions Age-related hearing loss is the risk factor for the cognitive impairment, especially for abstraction and orientation, in the elderly. The self-reported hearing loss is an independent risk factor for cognitive impairment.