[Research progress in pH-responsive antibacterial nanomaterials for inhibiting oral plaque biofilms].

pH-responsive antibacterial nanomaterials are a new type of nanomaterials that can selectively undergo structural changes and trigger drug release according to significant pH differences produced by the body under physiological and pathological conditions. The formation of acidic microenvironment in plaque is the key to the pathogenicity of oral plaque biofilm, which also creates conditions for the oral application of pH-responsive antibacterial nanomaterials. pH-responsive antibacterial nanomaterials can respond to changes in pH of plaque microenvironment and accurately control the release of antibacterial drugs, providing a new direction for improving drug efficacy and targeted antibacterial. The present article reviews the classification, mechanism and application of pH-responsive antibacterial nanomaterials in oral plaque inhibition.

PIWI/piRNA-mediated regulation of signaling pathways in cell apoptosis.

OBJECTIVE: This study aims to summarize the role of PIWIs/piRNAs in cell apoptosis through multiple signaling pathways. The PIWI-interacting RNAs (piRNAs) are among the small non-coding RNAs (sncRNAs) and are mainly expressed in germline cells. PIWI protein is the key to the biogenesis of piRNA. With the deepening of research in recent years, the PIWIs/piRNAs are expressed in a tissue-specific way in somatic cells outside the germline. In addition, researchers have found that the PIWIs/piRNAs play a regulatory role in cell apoptosis, proliferation, and necrosis by regulating key signaling pathways, such as PI3K/Akt signaling pathway, STAT signaling pathway, TGF-ß signaling pathway, and Fas signaling pathway at the transcriptional or post-transcriptional level. However, the PIWIs/piRNAs' role in cell apoptosis and its underlying mechanisms are still not fully understood. This study reviews the regulatory functions of PIWIs/piRNAs in apoptosis from the perspective of the signal pathway. MATERIALS AND METHODS: This study is a narrative review. PubMed and MEDLINE were used as the primary sources to search the following keywords: PIWI/piRNAs, signal pathway, pro-apoptotic, anti-apoptotic, and signaling pathway. RESULTS: PIWIs/piRNAs modulated pro-apoptotic or anti-apoptotic effects in a variety of cells: PIWIs/piRNAs through PI3K/Akt signaling pathway, STAT signaling pathway, TGF-ß signaling pathway, and Fas signaling pathway for pro-apoptotic or anti-apoptotic effects in cells. CONCLUSIONS: Apoptosis is a basic biological phenomenon of cell death, and it also has a great significance and complex molecular biological mechanisms. PIWI/piRNAs are closely related to various types of diseases and play a pro-apoptotic or anti-apoptotic role through the following pathways: PI3K/Akt signaling, STAT signaling, TGF-ß signaling, and Fas signaling pathways.

[Analysis of the catastrophic health expenditure of HIV-positive maternal households in high AIDS endemic areas in Liangshan prefecture].

Objective: To analysis the income and expenditure of HIV-positive pregnant women and the catastrophic health expenditure of their households in high AIDS endemic areas in Liangshan prefecture. Methods: From December 2018 to January 2019, a total of 250 pregnant women were recruited from 2 of 17 counties in Liangshan Prefecture, including 133 HIV-positive pregnant women and 117 HIV-negative pregnant women. The data, including basic information of pregnant women, basic information of the family, annual family income in 2017, annual family health expenditure in 2017, and maternal and child-related expenditure in 2017, were collected for analyzing the incidence of catastrophic health expenditure in the family. Results: The average annual income and average annual health expenditure of HIV-positive pregnant women households were 7 000 CNY and 2 000 CNY, while those of HIV-negative pregnant women households were 10 000 CNY and 3 000 CNY, respectively. Based on the criteria of 15%, 25% and 40%, the incidence of catastrophic health expenditure of HIV-positive pregnant households was 39.10%, 33.83% and 27.82%, with average differences of 34.84%, 31.17% and 26.65%, respectively, while that of HIV-negative pregnant women households was 38.46%, 33.33% and 23.93%, with average differences of 31.68%, 28.35% and 24.22%, respectively. Conclusion: The incidence of catastrophic health expenditure of pregnant households in high AIDS endemic areas in Liangshan prefecture is high. The incidence of HIV-positive families is slightly higher than that of HIV-negative families. We suggest that medical insurance compensation in Liangshan prefecture should be improved to reduce the impact of catastrophic health expenditure.

[HIV-1 drug resistance and influencing factors among people living with HIV/AIDS before antiretroviral therapy in Liangshan Yi Autonomous Prefecture].

Objective: To explore HIV-1 drug resistance and influencing factors among people living with HIV/AIDS before antiretroviral therapy in Liangshan Yi Autonomous Prefecture (Liangshan). Methods: Between January 1 and June 30, in both 2017 and 2018, a cross-sectional survey was conducted in Liangshan HIV-1 pol sequences were gathered and analyzed according to WHO Guidelines on HIV drug resistance surveillance of 2014. Both HyPhy 2.2.4 and Cytoscape 3.6.1 software were used to analyze the drug resistant strains of HIV-1 transmission network. Results: A total of 464 people living with HIV/AIDS was recruited. The proportion of HIV-1 CRF07_BC subtype was 88.6% (411/464), with HIV-1 drug resistance rate was 9.9% (46/464). The HIV-1 drug resistance rates of non-nucleoside reverse transcriptase inhibitors (NNRTI), nucleoside reverse transcriptase inhibitors(NRTI) and protease inhibitors (PI) were 6.7% (31/464), 1.9% (9/464) and 0.4% (2/464) respectively. New recombinant strains of HIV-1 URF_01BC subtype was independently clustered according to the drug resistant mutation sites. Results from the multivariate logistic analysis showed that injected drug users group had higher risk on HIV-1 drug resistance (aOR=3.03, 95%CI:1.40-6.54) than heterosexual group among people living with HIV/AIDS. Conclusions: HIV-1 drug resistance rate had already been in a high level before antiretroviral therapy was in place. The newly identified recombinant strains of HIV-1 URF_01BC subtype were independently clustered according to the drug resistant mutation sites. It was necessary to strengthen the prevention of the HIV-1 drug resistant strains transmission.

Laboratory studies of ultrasonic wave response of fractures with different lengths: Anisotropy characteristics and coda analysis.

Ultrasonic wave propagation in a synthetic medium with different scale fractures is investigated through the physics modeling research. The experiment model consisting of two layers, the first layer is divided into four fractured blocks with a constant fracture density but different dimension and a block without fractures as the reference region. The velocity and reflected amplitude of wave derived from the wide azimuth data processing are anisotropic due to the fractured layer. Coda wave characteristics versus offset and azimuth are obviously different for varying fracture scales. The ratio of wavelength and fracture dimension is an important parameter in the wave-fracture interaction based on the multiple scattering theory. When the wavelength of the incident wave is close to the fracture length, the scattering is dominant in the shot records and the waves are slowed and attenuated largely for the reflections from the bottoms of fractured layer and base model. The physical modeling results demonstrate that it is possible to extract fracture dimension and orientation information by analyzing code and primary waves from the reflection data.

[Current status on management and needs related to education and training programs set for new employees at the provincial Centers for Disease Control and Prevention, in China].

OBJECTIVE: In order to understand the current management status on education/training and needs for training among new employees working at the provincial CDC in China during 2012-2014, so as to provide basis for setting up related programs at the CDC levels. METHODS: Based on data gathered through questionnaire surveys run by CDCs from 32 provincial and 5 specifically-designated cities, microsoft excel was used to analyze the current status on management of education and training, for new employees. RESULTS: There were 156 management staff members working on education and training programs in 36 CDCs, with 70% of them having received intermediate or higher levels of education. Large differences were seen on equipment of training hardware in different regions. There were 1 214 teaching staff with 66 percent in the fields or related professional areas on public health, in 2014. 5084 new employees conducted pre/post training programs, from 2012 to 2014 with funding as 750 thousand RMB Yuan. 99.5% of the new employees expressed the needs for further training while. 74% of the new staff members expecting a 2-5 day training program to be implemented. 79% of the new staff members claimed that practice as the most appropriate method for training. CONCLUSIONS: Institutional programs set for education and training at the CDCs need to be clarified, with management team organized. It is important to provide more financial support on both hardware, software and human resources related to training programs which are set for new stuff members at all levels of CDCs.

Myocardial ischemic preconditioning upregulated protein 1(Mipu1):zinc finger protein 667 - a multifunctional KRAB/C2H2 zinc finger protein.

Myocardial ischemic preconditioning upregulated protein 1 (Mipu1) is a newly discovered upregulated gene produced in rats during the myocardial ischemic preconditioning process. Mipu1 cDNA contains a 1824-base pair open reading frame and encodes a 608 amino acid protein with an N-terminal Krüppel-associated box (KRAB) domain and classical zinc finger C2H2 motifs in the C-terminus. Mipu1 protein is located in the cell nucleus. Recent studies found that Mipu1 has a protective effect on the ischemia-reperfusion injury of heart, brain, and other organs. As a nuclear factor, Mipu1 may perform its protective function through directly transcribing and repressing the expression of proapoptotic genes to repress cell apoptosis. In addition, Mipu1 also plays an important role in regulating the gene expression of downstream inflammatory mediators by inhibiting the activation of activator protein-1 and serum response element.

Metallic electrical transport in inter-graphitic planes of an individual tubular carbon nanocone.

Tubular carbon cones (TCCs) with a herring-bone-like graphitic structure are synthesized on gold wire via the bias-assisted hot filament chemical vapor deposition (HFCVD) method. The electrical transport properties of an individual TCC are studied in the temperature range from 300 to 500 K by using a double probe scanning electron microscopy (DPSEM) in situ electrical measurement system. The high-resistance I-V characteristics of W-TCC-Au back-to-back double junctions show that electrons tunnel through the W-TCC junction, while thermoionic transport through the Au-TCC junction contributes to low-resistance properties. Temperature dependence of the electrical characteristics indicates that inter-graphitic-plane electrical transport in TCC is metallic.

[Roles of intercellar Ca2+ and protein kinase C played in tissue factor pathway inhibitor and tissue factor expression in human umbilic vein endothelial cells].

The purpose of the present study was to elucidate the roles that protein kinase C (PKC) and calcium played in the tissue factor (TF) synthesis and tissue factor pathway inhibitory (TFPI) release in human umbilic vein endothelial cells (HUVEC). A23187 was used to represent calcium ionophore and phorbol 12-myristate 13-acetate (PMA) as that of PKC activator. TF activity in the lysed HUVEC was measured using one stage clotting assay. TFPI activity in the conditioned medium of HUVEC was assessed by the two-step chromogenic method. The results showed that the TF activities in A23187, PMA and A23187 + PMA groups were remarkably higher (P < 0.01) than that in control. Among the three treated groups, the TF activities in both A23187 group and A23187 + PMA group were lower than that in the PMA group (P < 0.05), but the difference between the former two groups was statically insignificant (P > 0.05). In contrast to the control group, the TFPI activity in the A23187 group was not statistically different (P > 0.05). However, the TFPI activities in the PMA group and the A23187 + PMA group were markedly higher than those in the control group and the A23187 group (P < 0.01). These findings indicate that PKC and calcium ion promote TF synthesis in HUVEC but the effect of the former is stronger than that of the latter, and that the release of TFPI from HUVEC is facilitated by PKC and not significantly affected by calcium ion.

[Hemodialysis of uremic patients with a high risk of bleeding].

Sixty-three hemodialyses (HD) in 12 uremic patients with a high risk of bleeding were performed successfully. Sixty HD in 9 cases were done with low dose heparinization. An activated whole blood coagulation time (ACT) between 150 and 180 seconds was maintained during HD. Of these 60 HD, 54 were done in 5 patients with pericarditis, 4 were done in 2 patients with serious gastrointestinal (GI) bleeding and 2 were done in 2 patients with postoperative fresh wounds. Heparin-free dialysis was done once in each of 3 patients. Both blood tubing and hemodialyzer were flushed with physiologic saline periodically in one patient with normal ACT, who was a patient with postoperative fresh wound. But these were not flushed in two patients with remarkably prolonged ACT. Of these patients, the first one was with postoperative fresh wound and the second was with serious bleeding in the GI tract. Our experience shows that low dose heparinization or heparin-free dialysis are suitable for uremic patients with high risk of bleeding.