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101.
Environmental pollutants, including ambient particulate matter (PM), increase respiratory morbidity. Studies of model PM particles, including residual oil fly ash and freshly generated diesel exhaust particles, have demonstrated that PM affects inflammatory airway responses. Neither of these particles completely represents ambient PM, and therefore questions remain about ambient particulates. We hypothesized that ambient PM of different size fractions collected from an urban environment (New York City air), would activate primary culture human bronchial epithelial cells (HBECs). Because of the importance of granulocyte-macrophage colony-stimulating factor (GM-CSF) on inflammatory and immunomodulatory processes, we focused our studies on this cytokine. We demonstrated that the smallest size fraction (ultrafine/fine; < 0.18 micro m) of ambient PM (11 micro g/cm(2)), upregulated GM-CSF production (2-fold increase). The absence of effect of carbon particles of similar size, and the day-to-day variation in response, suggested that the chemical composition, but not the particle itself, was necessary for GM-CSF induction. Activation of the extracellular signal-regulated kinase and the p38 mitogen-activated protein kinase was associated with, and necessary for, GM-CSF release. These studies serve to corroborate and extend those on model particles. Moreover, they emphasize the role of the smallest size ambient particles in airway epithelial cell responses.  相似文献   
102.

Purpose

Nuclear cardiology is widely used to diagnose coronary artery disease and to guide patient management, but data on current practices, radiation dose-related best practices, and radiation doses are scarce. To address these issues, the IAEA conducted a worldwide study of nuclear cardiology practice. We present the European subanalysis.

Methods

In March 2013, the IAEA invited laboratories across the world to document all SPECT and PET studies performed in one week. The data included age, gender, weight, radiopharmaceuticals, injected activities, camera type, positioning, hardware and software. Radiation effective dose was calculated for each patient. A quality score was defined for each laboratory as the number followed of eight predefined best practices with a bearing on radiation exposure (range of quality score 0 – 8). The participating European countries were assigned to regions (North, East, South, and West). Comparisons were performed between the four European regions and between Europe and the rest-of-the-world (RoW).

Results

Data on 2,381 European patients undergoing nuclear cardiology procedures in 102 laboratories in 27 countries were collected. A cardiac SPECT study was performed in 97.9 % of the patients, and a PET study in 2.1 %. The average effective dose of SPECT was 8.0?±?3.4 mSv (RoW 11.4?±?4.3 mSv; P?<?0.001) and of PET was 2.6?±?1.5 mSv (RoW 3.8?±?2.5 mSv; P?<?0.001). The mean effective doses of SPECT and PET differed between European regions (P?<?0.001 and P?=?0.002, respectively). The mean quality score was 6.2?±?1.2, which was higher than the RoW score (5.0?±?1.1; P?<?0.001). Adherence to best practices did not differ significantly among the European regions (range 6 to 6.4; P?=?0.73). Of the best practices, stress-only imaging and weight-adjusted dosing were the least commonly used.

Conclusion

In Europe, the mean effective dose from nuclear cardiology is lower and the average quality score is higher than in the RoW. There is regional variation in effective dose in relation to the best practice quality score. A possible reason for the differences between Europe and the RoW could be the safety culture fostered by actions under the Euratom directives and the implementation of diagnostic reference levels. Stress-only imaging and weight-adjusted activity might be targets for optimization of European nuclear cardiology practice.
  相似文献   
103.
Effective bidirectional communication between attending physicians and long-term care facilities is of critical importance to ensure timely, appropriate, and high-quality care that is responsive to residents' needs, values, and preferences. Ongoing communication with residents and residents' families is essential to the establishment of mutual trust and respect. This earned trust and respect in turn promotes frank discussions among long-term care practitioners and the facility staff who can then better guide residents and families through difficult care decisions.  相似文献   
104.
105.
Background: Misconnections between enteral supplies and other access devices have led to significant morbidity and mortality. To reduce misconnections, a standard small‐bore connector has been developed (International Organization for Standards 80369‐8; ENFit). The full impact of transition to this connector is not known, however. Method: Working with major manufacturers and Food and Drug Administration, we obtained ENFit and comparative legacy tubes of variable sizes (low‐profile, 14F, 18F, 20F, and 24F balloon gastrostomies). Gravity enteral feeding was simulated with an empty bolus syringe attached to the feeding tube to be tested. The tube was clamped and filled to the 60‐mL mark with liquid (water, Jevity 1 Cal, Isosource HN, Isosource 1.5 Cal, Two Cal HN, and Nourish). The clamp was released, and time for formula to leave the syringe was recorded. Results: There was no difference in flow rate between the aggregate legacy and ENFit tubes for the low‐profile, 18F, and 20F sizes. The ENFit 14F tubes had a lower flow rate vs the legacy tubes, largely due to the low flow rates seen with the 1 ENFit tube. Similarly, 24F ENFit tubes with some formulas yielded lower flow rates as opposed to legacy. Conclusion: Overall, for the low‐profile, 18F, and 20F sizes, the ENFit tubes had similar flow rates when compared with the legacy tubes. For the 14F and 24F sizes, the flow rate of ENFit tubes was significantly lower, which could result in longer EN delivery for patients who are using these tubes to provide gravity feeding.  相似文献   
106.
Interaction between analgesic and various psychotropic drugs constitute a subject of many research investigations. Literature data considering this issue are often inconsistent. Sertraline is one of the most potent drugs in the family of selective serotonine reuptake inhibitors (SSRIs). The influence of sertraline (5 mg/kg) on antinociceptive effect of morphine (10 mg/kg), metamizol (500 mg/kg) and indomethacin (10 mg/kg or 1.4 mg/kg) was investigated in a mouse model using the tail-flick and hot-plate tests. All drugs were injected intraperitoneally. Sertraline was administered to mice 30 min before applying the analgesic drugs. Measurement of nociception was performed within 2 h after sertraline administration. The research studies were futher conducted with multiple (14 days) drug dosage. Sertraline after single dose increased the antinociceptive effect of morphine (in the hot-plate test) and metamizol and indomethacin (only in the tail-flick test). Sertraline after 14 day administration decreased analgesic effect of morphine (only in the hot-plate test). Sertraline applied for 14 days increased the antinociceptive effect of indomethacin. Sertraline alone after multiple doses increased pain reaction time. The results of experiments suggest the role of sertraline in nociception and possibility of interaction between sertraline and analgesic drugs.  相似文献   
107.
Naturally occurring phenolics, protocatechuic and tannic acids have been reported to be inhibitors of chemical mutagenesis and carcinogenesis in experimental models. Here, we have studied the effect of pretreatment with these compounds on MC-induced cytochrome P450 and phase II enzymes in rats. The male Wistar rats were treated intraperitoneally with protocatechuic acid and tannic acid in the dose of 50mg/kg every 3 days for 2 weeks. MC was administered at the 12th day of phenolics treatment. The activities of EROD (CYP1A1), MROD (CYP1A2), PROD (CYP2B), PNPH (CYP2E1), GST, UDPGT, NQO1 were measured in the liver and kidney. Protocatechuic acid treatment minimally reduced the MC-induced EROD and MROD, but the observed differences were statistically significant. This compound was also a weak inhibitor of hepatic PNPH. Moreover, Western blot analysis with CYP1A1/1A2- and CYP2E1-specific antibodies showed the same effect in the levels of hepatic CYP1A1/1A2 and CYP2E1. Minimal decrease of renal constitutive (by 23%) and more significant reduction of induced form (by 66%) of PNPH was found as result of treatment with protocatechuic acid. Tannic acid alone had no effect on cytochrome P450 enzymes while in combination with MC this polyphenol minimally enhanced the MC induction of MROD and in greater extent PNPH in liver. The treatment with protocatechuic acid alone enhanced slightly the activities of all three phase II enzymes in liver. The pretreatment with this phenolic of the MC-induced rats however significantly increased the activities of hepatic GST and NQO1 in comparison with MC-treated group. In kidney MC-induced activity of NQO1 was reduced (about 43%) to the control level by tannic acid pretreatment. The results of our present study indicate that in rat the prolonged treatment with protocatechuic acid affects differently the activities of CYP and phase II enzyme when compared to tannic acid. Moreover, the effect of this polyphenols significantly depends on the method of treatment.  相似文献   
108.

Background

Nationally, the use of long-acting reversible contraception (LARC), specifically intrauterine devices (IUDs) and implants, by teens remains low, despite their effectiveness, safety, and ease of use.

Methods

To examine patterns in use of LARC among females aged 15–19 years seeking contraceptive services, CDC and the U.S. Department of Health and Human Services’ Office of Population Affairs analyzed 2005–2013 data from the Title X National Family Planning Program. Title X serves approximately 1 million teens each year and provides family planning and related preventive health services for low-income persons.

Results

Use of LARC among teens* seeking contraceptive services at Title X service sites increased from 0.4% in 2005 to 7.1% in 2013 (p-value for trend <0.001). Of the 616,148 female teens seeking contraceptive services in 2013, 17,349 (2.8%) used IUDs, and 26,347 (4.3%) used implants. Use of LARC was higher among teens aged 18–19 years (7.6%) versus 15–17 years (6.5%) (p<0.001). The percentage of teens aged 15–19 years who used LARC varied widely by state, from 0.7% (Mississippi) to 25.8% (Colorado).

Conclusions

Although use of LARC by teens remains low nationwide, efforts to improve access to LARC among teens seeking contraception at Title X service sites have increased use of these methods.Implications for public health practice: Health centers that provide quality contraceptive services can facilitate use of LARC among teens seeking contraception. Strategies to address provider barriers to offering LARC include: 1) educating providers that LARC is safe for teens; 2) training providers on LARC insertion and a client-centered counseling approach that includes discussing the most effective contraceptive methods first; and 3) providing contraception at reduced or no cost to the client.  相似文献   
109.
The mouse skin carcinogenesis is unique model for our understating of molecular events leading to tumor development. The tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA) activates a variety of signaling pathways, including MAPK/AP-1. In this study, we examined the time course of EGFR phosphorylation and AP-1 activation in mouse epidermis after topical application of a single 10 nmol dose of TPA. Remarkable differences in the phosphorylation kinetics of EGFR tyrosine residues were observed. While the maximal level of Y1068 tyrosine phosphorylation occurred 4 h after TPA treatment, the Y1173 residue phosphorylation was initially down-regulated, and reached the highest level after 24 h. Phosphorylation of Y1068 tyrosine was correlated with AP-1 activation and c-Jun N-terminal kinase (JNK) activity. These results indicate that the stimulation of AP-1 in mouse epidermis by TPA may be the effect of EGFR activation, but not all tyrosine residues forming its catalytic center are equally involved in this process.  相似文献   
110.
BackgroundThe biological effects and health implications of electromagnetic field (EMF) associated with cellular mobile telephones and related wireless systems and devices have become a focus of international scientific interest and world-wide public concern. It has also been proved that EMF influences the production of reactive oxygen species (ROS) in different tissues.MethodsExperiments were performed in healthy rats and in rats with persistent inflammatory state induced by Complete Freund's Adjuvant (CFA) injection, which was given 24 h before EMF exposure and drug application. Rats were injected with CFA or the same volume of paraffin oil into the plantar surface of the left hind paw. Animals were exposed to the far-field range of an antenna at 1800 MHz with the additional modulation which was identical to that generated by mobile phone GSM 1800. Rats were given 15 min exposure, or were sham-exposed with no voltage applied to the field generator in control groups. Immediately before EMF exposure, rats were injected intraperitoneally with tramadol in the 20 mg/kg dose or vehicle in the 1 ml/kg volume.ResultsOur study revealed that single EMF exposure in 1800 MHz frequency significantly reduced antioxidant capacity both in healthy animals and those with paw inflammation. A certain synergic mode of action between applied electromagnetic fields and administered tramadol in rats treated with CFA was observed.ConclusionsThe aim of the study was to examine the possible, parallel/combined effects of electromagnetic radiation, artificially induced inflammation and a centrally-acting synthetic opioid analgesic drug, tramadol, (used in the treatment of severe pain) on the antioxidant capacity of blood of rats. The antioxidant capacity of blood of healthy rats was higher than that of rats which received only tramadol and were exposed to electromagnetic fields.  相似文献   
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