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61.
With the population aging, total joint replacements which are an effective method to restore patient’s mobility are an increasing necessity. However, such operations are known to entail serious blood loss, which may have dramatic consequences in patients with chronic diseases or when the prosthesis is revised, a situation where the blood loss is even higher. Therefore, formulas to better estimate the blood loss are available. These formulas may also be used for clinical studies to compare blood loss between different joint replacement techniques. The aim of this review is to provide a clear understanding of the formulas and to help physicians to further improve their blood loss estimation. Moreover, surgeons will then be able to choose the most accurate and user-friendly formula for more comparable data between clinical studies.  相似文献   
62.
BackgroundVentilator associated pneumonia (VAP) is an important source of morbidity and mortality in patients receiving mechanical ventilation. VAP is associated with prolongation of mechanical ventilation, ICU and hospital stay and increases in costs.MethodsQuality improvement project. Mechanically ventilated patients received oral care every 8 h with chlorhexidine 2%. A formal process was developed to evaluate compliance with the following ventilator bundle initiatives: head of the bed elevation to 30–45°, daily sedation vacation and assess the readiness to extubate, providing peptic ulcer disease prophylaxis and providing deep vein thrombosis prophylaxis (unless contraindicated).ResultsThe rate of VAP before starting the project, in the first 6 months of year 1431H, was 16.2 cases/1000 ventilator days. Six month after inception of the quality improvement project, the VAP rates decreased to 5.6 cases/1000 ventilator days at the end of 1431H, and at the end of 1432H, it was 5.5 cases/1000 ventilator days. This leads to significant reduction in mortality (adjusted according to APACHE II) from 23.4% to 19.1% (p value 0.024) and the length of stay in ICU from 9.7 to 6.5 days (p value 0.00002).ConclusionThe combination of regular oral hygiene with chlorhexidine 2% and rigorous implementation of ventilator care bundle was associated with significant reduction in VAP rate in mechanically ventilated patients. This has led to reduction in length of stay in ICU from 9.7 to 6.5 days and reduction in mortality from 23.4% to 19.1%.  相似文献   
63.
Periodontitis appears to promote chronic inflammatory diseases, including atherosclerosis, but relevant mechanisms need clarification. Oral bacteria induce antibodies that bind not only bacteria, but also oxLDL. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans induce remarkable IgG responses that are dominated by IgG2, and IgG2 is IFN-γ-dependent and is promoted by dendritic cells (DCs). LDL-reactive antibodies induced by P. gingivalis and A. actinomycetemcomitans include anti-phosphorylcholine (α-PC) and β2-glycoprotein-1-dependent anticardiolipin (α-CL), and these antibodies may link chronic inflammatory diseases at a mechanistic level. Antibody-mediated uptake of oxLDL or bacteria dramatically enhances DC-IL-12, and DC-IL-12 induces NK-cell-IFN-γ responses that promote Th-1 responses and sustained inflammation. DCs may be derived from monocytes, and this is striking in cultures of aggressive periodontitis (AgP) monocytes, where DC numbers are about double control levels. Moreover, serum α-CL levels in individuals with AgP are frequently elevated, and these antibodies promote atherosclerosis in persons with antiphospholipid syndrome. Elevated serum levels of soluble-intercellular adhesion molecule, soluble-vascular cell adhesion molecule, and soluble-E-selectin are atherosclerosis-associated indicators of vascular inflammation, and these markers are elevated in the subset of AgP patients with high α-CL. We reason that periodontitis patients with elevated antibodies reactive with oxLDL could be a subgroup at high risk for cardiovascular sequelae.  相似文献   
64.
During cancer treatment, doses must be carefully administered and monitored to guarantee efficacy and minimize side-effects. A potentiometric sensor was developed for the direct real-time assay of a widely used antineoplastic drug (vinblastine (VB)) in plasma samples. Membrane cocktails were drop-casted over a glassy-carbon electrode coated with a lipophilic conducting polymer (polyaniline). The study investigated five cation exchangers, five plasticizers (of different polarities and dielectric constants), and four ionophores with different physicochemical characters on the sensor performance. The study substantiates a data-driven selection of the optimum membrane recipe. The latter included sodium tetraphenylborate as an ion exchanger, dioctylphthalate as a plasticizer, and hydroxypropyl-β-cyclodextrin as ionophore. The membrane proved a near-Nernstian slope of 37.5 mV per decade, a LOQ of 2.99 × 10−6 M, and a stable fast response. The selectivity study proved poor responses to common physiological ions. The developed sensor was used for the determination of VB in its pure powder form, marketed formulation, and plasma samples. The fast and direct sensor response enables a wide range of applications in quality control laboratories and clinical studies.

Potentiometric glassy carbon electrode for determination of vinblastine.  相似文献   
65.
66.
The macrocycle para-sulfonatocalix[8]arene, sCX[8], was examined with 2 antibiotic drugs, ciprofloxacin (CIP) and isoniazid. The drugs were shown to form complexes with sCX[8] using proton nuclear magnetic resonance, thermogravimetric analysis, fluorescence spectroscopy, and molecular modeling. Both drugs form 1:1 hydrated (H2O: 13%-14% w/w) host-guest complexes, with sCX[8] binding around the pyridine ring of isoniazid, and around the piperazine and cyclopropane rings of CIP. From proton nuclear magnetic resonance, the binding constant of isoniazid to sCX[8] was 6.8 (±0.3) × 103 M?1. Addition of 2 equivalents of sCX[8] to CIP resulted in a 58% decrease in fluorescence, and time-resolved fluorescence anisotropy of CIP doubles with sCX[8]. Each drug binds into the cavity of the macrocycle, with binding stabilized via combinations of hydrogen bonding, electrostatic interactions, π-π stacking, and hydrophobic effects. The safety of sCX[8] was examined in vitro with human embryonic kidney 293 cells. The IC50 of sCX[8] was 559 μM, which is a minimum of 5-fold higher than the concentration that would be used in the clinic. The in vitro effect of sCX[8] on the action of CIP was examined on a panel of bacterial lines. The results showed that sCX[8] has no inherent antibiotic activity and had no negative effect on the action of CIP.  相似文献   
67.
Hit, Lead & Candidate Discovery
Inflammation is a complex biological process that is generally occurs in response to pathological triggers. Both neurodegenerative diseases and cancer have been linked to inflammation. The analgesic and anti‐inflammatory effects of cupressuflavone (CUF) isolated from Cupressus macrocarpa were examined. The analgesic effects of CUF (40, 80 and 160 mg/kg po) were assessed in the acetic acid‐induced writhing and hot plate models in mice with diclofenac sodium as the reference standard (100 mg/kg). CUF dose‐dependently inhibited the writhing response in mice by 25, 48, and 62%, at the three CUF doses with 160 mg/kg being equivalent to the diclofenac control. CUF dose‐dependently increased the hot plate model reaction time with a maximal effect after 120 min. In the carrageenan‐induced paw edema model of inflammation, CUF demonstrated anti‐inflammatory activity by inhibiting paw edema by 55, 60, and 64% at doses of 40, 80, and 160 mg/kg po, respectively. CUF also reduced the plasma pro‐inflammatory mediators PGE2 (44, 54, and 58%), TNF‐α (26, 37, and 53%), IL‐1β (19, 33, and 41%), and IL‐6 (32, 44, and 55%) at the three doses tested with the highest dose having similar effects to diclofenac sodium (100 mg/kg). This finding from this study indicates that CUF has both analgesic and anti‐inflammatory effects.  相似文献   
68.

Purpose

Monitoring process conditions during lyophilization is essential to ensuring product quality for lyophilized pharmaceutical products. Residual gas analysis has been applied previously in lyophilization applications for leak detection, determination of endpoint in primary and secondary drying, monitoring sterilization processes, and measuring complex solvents. The purpose of this study is to investigate the temporal evolution of the process gas for various formulations during lyophilization to better understand the relative extraction rates of various molecular compounds over the course of primary drying.

Methods

In this study, residual gas analysis is used to monitor molecular composition of gases in the product chamber during lyophilization of aqueous formulations typical for pharmaceuticals. Residual gas analysis is also used in the determination of the primary drying endpoint and compared to the results obtained using the comparative pressure measurement technique.

Results

The dynamics of solvent vapors, those species dissolved therein, and the ballast gas (the gas supplied to maintain a set-point pressure in the product chamber) are observed throughout the course of lyophilization. In addition to water vapor and nitrogen, the two most abundant gases for all considered aqueous formulations are oxygen and carbon dioxide. In particular, it is observed that the relative concentrations of carbon dioxide and oxygen vary depending on the formulation, an observation which stems from the varying solubility of these species. This result has implications on product shelf life and stability during the lyophilization process.

Conclusions

Chamber process gas composition during lyophilization is quantified for several representative formulations using residual gas analysis. The advantages of the technique lie in its ability to measure the relative concentration of various species during the lyophilization process. This feature gives residual gas analysis utility in a host of applications from endpoint determination to quality assurance. In contrast to other methods, residual gas analysis is able to determine oxygen and water vapor content in the process gas. These compounds have been shown to directly influence product shelf life. With these results, residual gas analysis technique presents a potential new method for real-time lyophilization process control and improved understanding of formulation and processing effects for lyophilized pharmaceutical products.
  相似文献   
69.

Background

Smoking is a major risk factor for death-related diseases. Not all healthcare professionals are following evidence-based guidelines for smoking cessation counseling in primary care settings. The WHO, Framework Convention on Tobacco Control (FCTC), and United States Public Health Service (USPHS) guidelines recommend that all healthcare professionals, including students in healthcare training programs, receive education in the management of tobacco use and dependence.

Objective

To evaluate the effect of training programs for primary healthcare physicians on the knowledge, attitude, and practice of smoking cessation counseling.

Methods

This was a pre-post intervention study. The study included 74 primary care physicians working in primary healthcare centers affiliated with the Ministry of Health and Suez Canal University Hospitals in Port Said City. The study was conducted between June 2015 and March 2016 using a structured questionnaire and observation checklist to assess counseling of patients willing to quit smoking.

Results

There were highly statistically significant improvements in the physicians’ median scores of knowledge (30%–80%), attitude (65% -100%), and practice (20%–70%) (p?<?0.001) pre-post intervention. The most frequent correct knowledge was consequences of smoking (73%–87.3%) (p?<?0.001) pre-post intervention. The most favorable attitude was the importance of smoking cessation (70.3%–100%) (p?<?0.001) pre-post intervention. The best observed correct practice was asking about smoking (70.3%–100%) (p?<?0.001) pre-post intervention.

Conclusion

Knowledge, attitude, and practice skills regarding smoking cessation counseling among primary healthcare physicians were markedly improved after implementation of the education program.
  相似文献   
70.
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