[Effect of occupational stress on recurrent spontaneous abortion in women of childbearing age].

Objective: To investigate the influence of occupational stress on recurrent spontaneous abortion (RSA) in women of childbearing age. Methods: From January to December, 2017, 75 working women of childbearing age (25-35 years) who were admitted to a provisional hospital in Lanzhou, China and diagnosed with RSA were assigned into patient group. At a 1∶4 ratio, 300 age-matched working women who had normal first pregnancy were randomly selected as controls. A case-control study was conducted by a self-made questionnaire and the effort-reward imbalance scale. The impact of occupational stress on RSA in women of childbearing age was analyzed by evaluation of occupational harmful factors, regularity, effort-reward ratio, and sleep quality. Results: There were significant differences in the distribution of sleep, daily exercise, night shift, extrinsic-effort/low-reward score, and effort/low-reward score between the patient group and the control group (χ(2)=7.867, P<0.05; χ(2)=7.377, P<0.05; χ(2)=3.714, P<0.05; χ(2)=6.651, P<0.05; χ(2)=8.556, P<0.05) . With controlled factors such as general conditions and living habits, logistic regression analysis showed that poor sleep quality and high-effort/low-reward were risk factors for RSA (odds ratio[OR]=1.462, 95% confidence interval[CI]: 1.032~2.073; OR=3.253, 95%CI: 1.169~9.053) . A regular work was a protective factor against RSA (OR=0.644, 95%CI: 0.438-0.946) . Conclusion: In occupational stress, irregular working hours, lack of sleep, and high-effort/low-reward are risk factors for RSA. Working women of childbearing age should ensure adequate sleep, pay attention to effort-reward balance, and make a regular work schedule.

[Study on clinical symptoms and influencing factors of influenza-associated severe acute respiratory illness in children younger than 5 years old in Suzhou of China, 2011-2017].

Objective: To study the influencing factors of influenza-associated severe acute respiratory illness (SARI) in children younger than 5 years of old in Suzhou, and to provide evidence to support the improvement of prevention and control strategies for influenza in children. Methods: We conducted a prospective influenza surveillance for hospitalized SARI and outpatient influenza-like illness (ILI) at Children's Hospital of Soochow University from April 2011 to March 2017. We compared the clinical and other characteristics of influenza-positive patients with SARI to those with ILI to find the differences and to identify influencing factors of influenza-associated SARI, using χ2 test and unconditional logistic regression. Results: We found 786 cases of influenza-associated ILI and 413 cases of influenza-associated SARI during the study period. Cough, runny nose, shortness of breath, asthma or wheezing were more common in influenza-associated SARI than in influenza-associated ILI (P<0.01). Univariate and multivariate logistic regression showed that the influencing factors which significantly associated with increased risk of influenza-associated SARI were as follows: younger age (<6 months OR=3.6, 6-23 months aOR=2.5), respiratory infection history within 3 months (aOR=4.5), chronic lung disease history (OR=3.4), fever above 39.0 ℃ (39.0-39.9 ℃ aOR=2.4, ≥40.0 ℃ aOR=6.0), and the presence of A/H1N1 (aOR=2.3), A/H3N2 (aOR=1.9). Conclusion: Children younger than 2 years old, with a history of chronic lung disease, a history of respiratory infection within 3 months, or with a fever peak above 39.0 ℃ should seek medical advice as soon as possible or receive annual influenza vaccination to reduce the incidence of influenza-associated serious outcomes.

[Estimation of hospitalization rate of Haemophilus influenzae associated community-acquired pneumonia in children under 5 years in Suzhou, 2010-2014].

Objective: To estimate the hospitalization rate of Haemophilus (H.) influenzae associated community-acquired pneumonia in children under 5 years in Suzhou. Methods: From 2010 to 2014, medical records and bacteriology results of children under 5 years hospitalized with community-acquired pneumonia in Children's Hospital of Soochow University were collected, retrospectively. Detection rate of H. influenzae was describe. The hospitalization rate of H. influenzae associated community-acquired pneumonia was estimated using the number of local children in urban area of Suzhou, which was obtained from the immunization platform of Suzhou Center for Disease Prevention and Control. Results: A total of 28 043 hospitalized pneumonia cases were included from 2010 to 2014, in which 19 526 (69.63%) had bacteriological examination. The overall detection rate of H. influenzae was 11.06% (2 160/19 526), and children aged 12-23 months had the highest positive rate (14.29%, 550/3 850), and the rate was higher during winter-spring than during summer-autumn (χ2=455.11,P<0.01). The average hospitalization rate of H. influenzae associated pneumonia in children under 5 years was 760.36/100 000 (95%CI: 733.70/100 000-787.01/100 000), which was higher in winter and spring (898.79/100 000 and 1 249.52/100 000) than in summer and autumn (514.35/100 000 and 359.04/100 000), and the hospitalization rate was higher in boys (942.12/100 000) than in girls (563.76/100 000), the differences were all significant (P<0.01). The highest hospitalization rate was observed in children aged 1-5 months (2 478.31/100 000) and the hospitalization rate decreased with age (χ2=2 129.80, P<0.01). Conclusion: There was a considerable burden of H. influenzae associated community-acquired pneumonia in children under 5 years in Suzhou, especially in children under 6 months.

Nanobelts of semiconducting oxides.

Ultralong beltlike (or ribbonlike) nanostructures (so-called nanobelts) were successfully synthesized for semiconducting oxides of zinc, tin, indium, cadmium, and gallium by simply evaporating the desired commercial metal oxide powders at high temperatures. The as-synthesized oxide nanobelts are pure, structurally uniform, and single crystalline, and most of them are free from defects and dislocations. They have a rectanglelike cross section with typical widths of 30 to 300 nanometers, width-to-thickness ratios of 5 to 10, and lengths of up to a few millimeters. The beltlike morphology appears to be a distinctive and common structural characteristic for the family of semiconducting oxides with cations of different valence states and materials of distinct crystallographic structures. The nanobelts could be an ideal system for fully understanding dimensionally confined transport phenomena in functional oxides and building functional devices along individual nanobelts.

A combined theoretical and experimental investigation of uranium dioxide under high static pressure.

We have investigated the behavior of uranium dioxide (UO2) under high static pressure using a combination of experimental and theoretical techniques. We have made Raman spectroscopic measurements up to 87 GPa, electrical transport measurements up to 50 GPa from 10 K to room temperature, and optical transmission measurements up to 28 GPa. We have also carried out theoretical calculations within the GGA + U framework. We find that Raman frequencies match to a large extent, theoretical predictions for the cotunnite (Pnma) structure above 30 GPa, but at higher pressures some behavior is not captured theoretically. The Raman measurements also imply that the low-pressure fluorite phase coexists with the cotunnite phase up to high pressures, consistent with earlier reports. Electrical transport measurements show that the resistivity decreases by more than six orders of magnitude with increasing pressure up to 50 GPa but that the material never adopts archetypal metallic behavior. Optical transmission spectra show that while UO2 becomes increasingly opaque with increasing pressure, a likely direct optical band gap of more than 1 eV exists up to at least 28 GPa. Together with the electrical transport measurements, we conclude that the high pressure electrical conductivity of UO2 is mediated by variable-range hopping.

Synthesis and thermoelectric power of nitrogen-doped carbon nanotubes.

We have previously shown that high-purity multiwalled carbon nanotubes (pristine MWNTs) can be prepared from a mixture of xylene-ferrocene (99 at% C:1 at% Fe) inside a quartz tube reactor operating at approximately 700 degrees C. In a similar process, approximately 3 g of melamine (C3H6N6) was introduced during the growth of MWNTs to prepare nitrogen-doped nanotubes. The structural and electronic properties of nitrogen-doped MWNTs were determined by scanning electron microscopy, high-resolution transmission electron microscopy (HRTEM), electron energy loss spectroscopy (EELS), and thermopower measurements. The individual nitrogen-doped nanotube exhibits a bamboo-like structure and comprises 6-16 tube walls, as evidenced by HRTEM studies. The EELS measurements yielded an average nitrogen content of approximately 5 at% in the doped tubes. The thermoelectric power data of nitrogen-doped MWNTs remained negative even after exposure to oxygen for an extended period of time, suggesting that nitrogen doping of MWNTs renders them n-type, consistent with scanning tunneling spectroscopic studies on similar nanotubes.

[Synthesis and antimalarial as well as antitumor activities of 2,4-diamino-6-(N-methyl-substituted benzylamino) quinazolines].

Sixteen 2,4-diamino-6-(N-methyl-substituted benzylamino) quinazolines (I) were synthesized by two different methods. 2-Nitro-5-chloro-benzonitrile was treated with the appropriate N-methyl-substituted benzylamines and I was formed after reduction and cyclization. Another method was reductive methylation, i.e., 2,4-diamino-6-substituted benzylaminoquinazolines reacted with formaldehyde and sodium cyanoborohydride at pH 6.3. Suppressive therapeutic tests in mice infected with Plasmodium berghei showed that four (I6,7,10,16) out of these compounds suppressed all the parasites when administered orally at the dose of 5 mg/kg and produced more than 99% suppression at 2.5 mg/kg. Eight compounds (I1,2,4,5,8-10,15) were found to have antitumor effects against Leukemia cells in culture comparable with or superior to those of the positive control methotrexate.

[Synthesis and biological activities of 2,4-diamino-5-fluoro-6-substituted benzylamino quinazolines].

The title compounds were synthesized by condensation of 5-fluoro- 2, 4, 6-triaminoquinazoline (6a) with various substituted benzaldehydes to produce the corresponding Schiff bases, followed by reduction. II and III were obtained by formylation and nitrosation of I, respectively, IV were obtained by reduction of II. Primary screening for suppressive therapeutic effects against P. berghei in mice showed that six of the twenty-two compounds produced 100% suppression when administered orally at a dose of 1 mg.kg-1. All compounds exhibited potent activity against L1210 cell in vitro. Among them I4 was more active than MTX. A number of compounds showed moderate activities against Diplococcus pneumoniae in vitro tests.

[Synthesis and biological activities of 2,4-diamino-5-chloro-6-substituted quinazolines].

Title compounds were synthesized by condensation of 5-chloro-2,4,6-triaminoquinazoline (8) with various substituted benzaldehydes to produce the corresponding Schiff bases, followed by reduction with NaBH4, II and III were obtained by formylation or nitrosation of I respectively. Primary screening for suppressive therapeutic effects against P. berghei in mice showed that eight of the twelve compounds produced 100% suppression when administered orally at dose of 20 mg/kg. The results against L1210 Leukemia cell and B16 melanoma cell in vitro exhibited potent inhibition. Among them four compounds were more active than MTX and SIPI 759. Further work is in process. Antibacterial tests in vitro showed that a number of compounds possessed moderate activities against Diplococcus pneumoniae.

[Studies on residual antimalarial activity of tripynadine in mice and monkeys].

This paper reports the experiments in which tripynadine free base at a dose 4.5 times that of ED50 was given to mice by intragastric administration. On the 20th day following the administration the mice were inoculated with 1 x 10(7) RBC infected with Plasmodium berghei ANKA strain. The infection rate was zero, implying that all mice had acquired protection. Although the residual activity time of tripynadine phosphate was longer than that of tripynadine free base or piperaquine phosphate, but tripynadine phosphate caused vomiting in monkeys during the medication. The residual antimalarial activity of tripynadine hydroxynaphthoate was less than that of tripynadine phosphate or tripynadine free base. A total dose of 200 mg/kg of tripynadine free base ensured residual antimalarial activity against P. cynomolgi bastianellii for 20 days. However, the residual activity decreased evidently when the total dose was reduced to 100 mg/kg. In short, it seems that the residual antimalarial activity of tripynadine free base is slightly less than that of piperaquine in monkeys.

[Observation on the efficacy of combined use of some new antimalarials for the treatment of falciparum malaria in Hainan Province].

Field trials were carried out to assess the therapeutic effects including the combined use of piperaquine (PQ) with nitroquine (NQ) and pyronaridine (PYR) with NQ against falciparum malaria in regions of Hainan Province with chloroquine-resistance in 3 successive autumns from 1985 to 1987. In an evaluation of PQ 750 mg with NQ 25 mg therapy in 33 falciparum malaria patients, the average fever subsidence time and parasite clearance time were 39 hours and 49 hours respectively, but within 28 days after medication, the recrudescence rates were 0-47% in different regions. In evaluations of PYR 600 mg with NQ 25 mg in 11 cases, PYR 800 mg with NQ 40 mg in 43 cases, PYR 800 mg with NQ 80 mg in 31 cases, the fever subsidence time were 31-35 hours, the parasite clearance time were 46-53 hours and the 28 days recrudescence rates were 13-18%. In the control, the use of PYR 1,200 mg alone in 42 cases, the average fever subsidence time and parasite clearance time were 33 hours and 48 hours respectively, the 28 days recrudescence rate was 12%. There was no statistically significant difference among them in their effects. The side-effects of all groups were mild.