Vital pulp therapy following pulpotomy in immature permanent teeth with carious exposure.

This prospective cohort study aimed to evaluate the clinical outcomes of vital pulp therapy (VPT) with the use of iRoot BP Plus (Innovative Bioceramics, Vancouver, Canada) for immature permanent teeth of patients aged from 6 to 10 years with pulp exposure resulting from dental caries and determine the impact of preoperative factors on VPT. Forty-six immature permanent teeth with dental caries underwent pulpotomy using iRoot BP Plus following a standardized protocol. Postoperative follow-ups were conducted on the first 3, 6 and 12 months post-surgery, then annually afterward. Successful treatment outcomes were defined based on clinical and radiographic evaluations. Statistical analysis was performed using the Fisher exact test, with p < 0.05 considered for statistical significance. Forty-four patients included in this study were 8.48 ± 1.49 years old and were followed up for 6 to 36 months. The overall success rate of pulpotomy was found to be 90.9% (40/44). None of the physical examination findings and symptoms significantly affected VPT prognosis (p > 0.05). Immature permanent teeth with caries-induced pulp exposed in patients aged 6 to 10 years can be effectively treated with pulpotomy using iRoot sBP Plus.

Effects of shift work schedules, compensatory sleep, and work-family conflict on fatigue of shift-working nurses in Chinese intensive care units.

BACKGROUND: Shift work is inevitable for nurses in intensive care units. Various studies explored nurses' fatigue in multiple hospital wards. However, few studies focused on fatigue among nurses in intensive care units. AIMS: To determine the association between shift work schedules, compensatory sleep, work-family conflict, and fatigue of shift-working nurses in critical care units. STUDY DESIGN: A descriptive cross-sectional multi-center study was conducted in March 2022 among intensive care nurses from five hospitals. METHODS: Data were collected by online survey, including self-designed demographic questions, the Fatigue Scale-14, the Chinese adult daytime sleepiness scale, and the work-family scale. Pearson correlation was conducted for bivariate analysis. Independent-sample t-test, one-way ANOVA, and multiple linear regression analysis were performed to examine fatigue-related variables. RESULTS: A total of 326 nurses responded to the survey with an effective response rate of 74.9%. The mean scores of physical fatigue and mental fatigue were 6.80 and 3.72, respectively. The bivariate analyses showed that work-family conflict was positively correlated with physical (r = 0.483, p < .001) and mental fatigue (r = 0.406, p < .001). Multiple linear regression results showed that work-family conflict, daytime sleepiness, and shift system were statistically significant factors influencing physical fatigue (F = 41.793, p < .001). Work-family conflict, sleep duration after the night shift, and daytime sleepiness were the main influencing factors of mental fatigue (F = 25.105, p < .001). CONCLUSIONS: Nurses with higher work-family conflict, daytime sleepiness, and working 12-h shifts have higher levels of physical fatigue. Higher work-family conflict, shorter sleep duration after night shifts, and daytime sleepiness are associated with higher mental fatigue among intensive care nurses. RELEVANCE TO CLINICAL PRACTICE: Nursing managers and nurses should consider work-family factors and compensatory sleep in their efforts to reduce fatigue. It is necessary to strengthen work-supporting strategies and compensatory sleep guidance for nurses to promote fatigue recovery.

Effects of a barium-based additive on gaseous and particulate emissions of a diesel engine.

The addition of barium-based additives is one of the main methods used to suppress smoke emissions in non-road diesel engines. Herein, a commercial barium-based additive was added to diesel fuel at the manufacturer's recommended concentration and used in a non-road four-cylinder supercharged diesel engine, without an after-treatment system, in bench experiments. Regulated emissions of the diesel engine were measured, volatile organic compounds (VOCs) and particulate matter (PM) were sampled. The carbonaceous fraction, water-soluble ions and inorganic elements in the PM were analyzed. Results indicated that the additive effectively reduced carbon monoxide (CO), hydrocarbon (HC) and smoke emissions from the engine. A 71% reduction in smoke was observed at the rated working condition, which was the maximum reduction of the three tested conditions. The additive produced a 36% reduction of VOCs at the rated working condition. The proportion of high carbon number hydrocarbons in the VOCs increased while the atmospheric reactivity of the VOCs decreased. The additive suppressed the concentration of organic carbon (OC) and elemental carbon (EC) emissions with a maximum reduction (40%) of total carbon achieved under the rated working condition. After the application of the additive, the concentration of water-soluble ions (Cl-, SO42-, NO3-, Na+, K+, Ca2+, NH4+) and elements (Fe, Mn, S, Ca, Ba) in the PM increased. A trend of increasing Barium content in the PM matched a similar trend of decreasing smoke.

Investigation on the adsorption characteristics and influencing factors of diesel engine exhaust particulate matter.

In the exhaust pipe, the adsorption process of diesel exhaust particulate matter (PM) is affected by the combination of its adsorption capacity and the environment. A diesel exhaust particle collection system was established to collect samples with different environmental conditions. The adsorption capacity of the samples was characterized by an isothermal adsorption test. Changes in sample characteristics were investigated by scanning electron microscope and thermogravimetric analyzer. The correlation analysis of the factors influencing the adsorption process was performed. The results showed that the diesel exhaust particulate matter has adsorption capacity, the pore diameter is distributed continuously in the range of 8 to 80 nm, and the specific surface area and pore structure parameters are similar to carbon black and belong to the category of mesopores and macropores. As the engine speed increased from 1500 to 3600 r·min-1, the specific surface area of samples increased from 65.408 to 101.885 m2·g-1, and the pore volume expanded from 0.093 to 0.152 mL·g-1, with a more complex pore structure and enhanced adsorption capacity. The samples at the outlet of the exhaust pipe had increased box dimension (DB), moisture, and soluble organic fraction (SOF) content compared to the samples at the inlet of the exhaust pipe. The activation energies (E) of the three samples were reduced by 34.77 kJ∙mol-1, 38.88 kJ∙mol-1, and 47.43 kJ∙mol-1, respectively. Among the influencing factors, the increase of hydrocarbon concentration contributes to the increase of adsorption volume and the reduction of E. The increase of the average temperature inhibits the increase of the DB, and the increase of the temperature difference between the inlet and outlet facilitates the adsorption of water and SOF by samples. The reduction of adsorption time is one of the main reasons for delaying the increase of DB. Average pore diameter has the largest positive correlation with the variation amount of DB, and the growth of the specific surface area and pore volume is the dominant reason for the improvement of adsorption capacity and oxidation activity.

A study of the fluorescence characteristics of common cariogenic microorganisms.

OBJECTIVE: To explore the fluorescence characteristics of common cariogenic bacteria: Streptococcus mutans, S. sanguis, Actinomyces viscosus, Prevotella intermedia, Lactobacillus acidophilus, and Candida albicans. METHODS: The bacteria were cultured on brain heart infusion (BHI) agar and BHI blood agar, and bacterial colonies were collected for further amplification in liquid medium. Bacterial suspensions in physiological saline were equally divided into three parts for bacteria counting, fluorescence spectrometry detection, and fluorescence microscope examination. RESULTS: The optimal excitation wavelength of the bacteria was 350 nm; their characteristic fluorescence peak position was at 436 ± 4 nm. There was a significant linear correlation between fluorescence intensity and bacterial concentration. The mean optical density (MOD) of S. mutans and L. acidophilus cultivated in BHI blood was significantly higher than that cultivated in BHI agar (110 ± 10 vs. 57 ± 20; 94 ± 16 vs. 31 ± 12, respectively, P < 0.05). The MOD of S. sanguis, A. viscosus, and P. intermedia cultivated in BHI blood agar was higher than that cultivated in BHI agar (37 ± 12 vs. 36 ± 11; 43 ± 17 vs. 38 ± 6; 86 ± 21 vs. 72 ± 8, respectively, P > 0.05); the opposite was observed for C. albicans. CONCLUSION: At 350 nm excitation wavelength, 436 ± 4 nm is an indicator for detecting six cariogenic bacteria. The fluorescence energy, Q, is a valuable index reflecting bacterial concentration under fluorescence spectrometry detection. Exogenous fluorescence groups have greater influence on fluorescence intensity and little influence on fluorescence peak position detection.

Novel hexagonal {V=O}6-containing sandwich-type cluster accompanied by in situ carbon-carbon bond formation of organic cations.

Two novel sandwich-type polyanions containing hexagonal {V=O}(6) group (H(2)tpy)(Hbpe)(3)H[(VO)(6)(SbW(9)O(33))(2)]·2H(2)O (1) and (H(2)tcy)(6)(Hbpp)(6)H(4)[VW(12)O(40)][(VO)(6)(SbW(9)O(33))(2)](3)·30H(2)O (2) (tpy = 4-(2,3,4-tri(pyridin-4-yl)butyl)pyridine, bpe = 1,2-(4-pyridyl)ethene, tcy = 1,2,4,5-tetra(pyridin-4-yl)cyclohexanol, bpp = 1,3-bis-(4-pyridyl)propane), were reported. Both compounds are built upon the complex hydrogen bonding networks of C-H···O and N-H···O occurred among inorganic anions and organic cations. Unusual in situ organic reactions involving C-C coupling are also observed in 1 and 2 regardless of the rigid bpe or flexible bpp. Compound 2 represents a rare case in which nano-sized α-Keggin [VW(12)O(40)](4-) and sandwich-type [(VO)(6)(SbW(9)O(33))(2)](6-) anionic clusters are present in a common crystal framework.

[Cloning and expression of Hgp44 from Porphyromonas gingivalis].

OBJECTIVE: To clone and express the gene of Hgp44 in adhesin domains of gingipains from Porphyromonas gingivalis (Pg) and to purify the protein. METHODS: The genomic DNA of Pg was isolated from PgATCC33277. The Hgp44 gene fragment was amplified by polymerase chain reaction (PCR) and then inserted into the cloning vector pMD18-T and sequenced. The correct fragment was linked with a prokaryotic expression vector pET-22b to construct the recombinant expression plasmid pET22b-Hgp44. The pET22b-Hgp44 confirmed by enzyme digestion was transformed into competent Escherchia coli (Ec) BL21 (DE3) cells. Expression of fusion protein was induced by isopropyl-ß-D-thiogalactoside (IPTG), and purified by immobilized metal-chelating affinity chromatography (IMAC) using a Ni(2+) matrix column. SDS-polyaerylamide gel electrophoresis (SDS-PAGE) and Western blotting analysis were used to examine the fusion protein. RESULTS: A 1 100 bp fragment was successfully amplified and verified by the agarose gel electrophoresis and sequencing. The generated recombinant expression vectors pET22b-Hgp44 were verified by enzyme digestion and agarose gel electrophoresis. The expression of fusion protein in Ec BL21 (DE3) cells was examined by SDS-PAGE and Western blotting analyses, and the data showed that the protein was 44 000 in size and expressed mostly in the form of inclusion body. The purification of fusion protein was achieved using Ni(2+) affinity chromatography. About 3.5 mg/L fusion protein was obtained. CONCLUSIONS: Hgp44 was successfully expressed in the prokaryotic expression system and purified by IMAC using a Ni(2+) matrix column.

Analysis of CD137 and CD137L expression in human primary tumor tissues.

AIM: To assess the expression of CD137 and CD137L in human primary tumor tissues and their potential role in tumor immunity. METHODS: Expression of CD137 and CD137L was assessed by immunohistochemistry in frozen sections of 12 human normal tissues, 15 benign tumors of epithelial or mesenchymal origin (adenoma and leiomyoma), and 36 malignant tumors of epithelial origin (squamous cell carcinoma and adenocarcinoma). The expression of CD137L on 9 human tumor cell lines (3 hepatocarcinoma, 2 lung carcinoma, 2 colon carcinoma, 1 lymphoma, and 1 leukemia) was detected by reverse transcription polymerase chain reaction. To analyze the role of CD137L expressed on tumor cells, we co-cultured tumor cells expressing CD137L with activated T lymphocytes expressing CD137 or with Chinese hamster ovary cells expressing CD137 and then detected by ELISA the levels of cytokines (IL-8, IFN-gamma) secreted by tumor cells or activated T cells. RESULTS: The expression of CD137 and CD137L was observed only in human benign (2/15, 3/15) or malignant tumors (15/36, 21/36), but not in normal tissues (0/12, 0/12). CD137 was expressed on the vessel walls within tumor tissues, whereas CD137L was expressed on tumor cells. The expression of CD137 and CD137L was more common in malignant tumors, especially in moderate or low-differentiated tumors. Furthermore, CD137L expression found on tumor cell lines was functional because the ligation of CD137L on lung squamous carcinoma cells L78 with CD137 on T cells induced IFN-gamma production by T cells, and ligation of CD137L on hepatocarcinoma cells HepG2.2.15 with CD137 triggered tumor cells to produce IL-8. CONCLUSION: CD137 and CD137L are expressed in different human primary tumor tissues, suggesting that they may influence the progression of tumors.