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1.
Introduction: Linezolid is an oxazolidinone antibiotic active against Gram-positive bacteria, and is most commonly used to treat life-threatening infections in critically ill patients. The pharmacokinetics of linezolid are profoundly altered in critically ill patients, partly due to decreased function of vital organs, and partly because life-sustaining drugs and devices may change the extent of its excretion.

Areas covered: This article is summarizes key changes in the pharmacokinetics of linezolid in critically ill patients. The changes summarized are clinically relevant and may serve as rationale for dosing recommendations in this particular population.

Expert opinion: While absorption and penetration of linezolid to tissues are not significantly changed in critically ill patients, protein binding of linezolid is decreased, volume of distribution increased, and metabolism may be inhibited leading to non-linear kinetics of elimination; these changes are responsible for high inter-individual variability of linezolid plasma concentrations, which requires therapeutic plasma monitoring and choice of continuous venous infusion as the administration method. Acute renal or liver failure decrease clearance of linezolid, but renal replacement therapy is capable of restoring clearance back to normal, obviating the need for dosage adjustment. More population pharmacokinetic studies are necessary which will identify and quantify the influence of various factors on clearance and plasma concentrations of linezolid in critically ill patients.  相似文献   
2.
Purpose: The aim of the paper was to develop the simple procedures for preparation of inclusion complexes of ellagic acid (EA) with cyclodextrins (CDs) and to investigate their antioxidant and antimicrobial activity.

Methods: The structural characterization was carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and nuclear magnetic resonance (NMR) methods. The phase solubility technique was used to investigate the interactions between ‘host’ and ‘guest’ molecules and to estimate the molar ratio between them. The antioxidant and antimicrobial activity of EA and inclusion complexes were determined.

Results: The apparent stability constants were found to be 117?dm3 mol?1 for the complex with β-CD and 161?dm3 mol?1 for the complex with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD). The results of phase-solubility studies showed that EA formed the inclusion complexes with CDs in the molar ratio of 1:1. The calculated half-maximal inhibitory concentration was 41.18?μg cm?3 for butyl hydroxy toluene, 1.96?μg cm?3 for EA, 0.88?μg cm?3 for inclusion complex with HP-β-CD, and 1.27?μg cm?3 for inclusion complex with β-CD.

Conclusion: The stability constants indicated the rapid release of EA from the inclusion complexes in the aqueous medium at 25?°C. The antioxidant activity of EA was increased, while the antimicrobial activity was preserved after complexation with CDs.  相似文献   

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Purpose

The main purpose of this study was to analyze the characteristics of dyspepsia and contributing factors in Montenegrin maintenance hemodialysis patients.

Methods

The study included 43 patients undergoing hemodialysis with symptoms of dyspepsia and 40 control dyspeptic subjects with preserved kidney function. All subjects underwent an interview about dyspeptic symptoms, physical and biochemical examination, and upper gastrointestinal endoscopy with pathohistological analysis of biopsy specimens.

Results

Early satiety, bloating and heartburn were the most common symptoms in hemodialysis patients but without significant difference in frequency in relation to controls. Chronic kidney disease patients had statistically lower concentration of total proteins and albumin (p?<?0.001), as well lower BMI values (p?=?0.002). Despite this, no significant correlation of laboratory parameters with dyspeptic symptoms was found. Pathohistological examination indicated that the most common finding in hemodialysis patients was chronic active gastritis (58%), while chronic atrophic gastritis was significantly more common in dialytic patients (p?=?0.032). Patients on hemodialysis had more frequently atrophy of corpus mucosa, which was positively related to dialysis duration (p?=?0.001) and negatively related to pH values (p?=?0.004) and bicarbonate concentration (p?=?0.049). Helicobacter pylori was considerably more common in patients who underwent shorter time on hemodialysis (p?<?0.001) and had higher values of bicarbonate (p?=?0.037).

Conclusion

Maintenance hemodialysis patients are at risk for chronic gastric diseases that correlated with both dialysis vintage and duration.

  相似文献   
5.
BACKGROUND Coronavirus disease 2019(COVID-19) significantly affected endoscopy practice,as gastrointestinal endoscopy is considered a risky procedure for transmission of infection to patients and personnel of endoscopy units(PEU).AIM To assess the impact of COVID-19 on endoscopy during the first European lockdown(March-May 2020).METHODS Patients undergoing endoscopy in nine endoscopy units across six European countries during the period of the first European lockdown for COVID-19(MarchMay 2020) were included. Prior to the endoscopy procedure, participants were stratified as low-or high-risk for potential COVID-19 infection according to the European Society of Gastrointestinal Endoscopy(ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates(ESGENA) joint statement, and contacted 7-14 d later to assess COVID-19 infection status. PEU were questioned regarding COVID-19 symptoms and/or infection via questionnaire, while information regarding hospitalizations, intensive care unitadmissions and COVID-19-related deaths were collected. The number of weekly endoscopies at each center during the lockdown period was also recorded.RESULTS A total of 1267 endoscopies were performed in 1222 individuals across nine European endoscopy departments in six countries. Eighty-seven(7%) were excluded because of initial positive testing. Of the 1135 pre-endoscopy low risk or polymerase chain reaction negative for COVID-19, 254(22.4%) were tested post endoscopy and 8 were eventually found positive, resulting in an infection rate of 0.7% [(95%CI: 0.2-0.12]. The majority(6 of the 8 patients, 75%) had undergone esophagogastroduodenoscopy. Of the 163 PEU, 5 [3%;(95%CI: 0.4-5.7)] tested positive during the study period. A decrease of 68.7%(95%CI: 64.8-72.7) in the number of weekly endoscopies was recorded in all centers after March 2020. All centers implemented appropriate personal protective measures(PPM) from the initial phases of the lockdown.CONCLUSION COVID-19 transmission in endoscopy units is highly unlikely in a lockdown setting, provided endoscopies are restricted to emergency cases and PPM are implemented.  相似文献   
6.
Since the beginning of their lives, all living organisms are exposed to the influence of geomagnetic fields.

Objectives

: With respect to the positive effects that magnetic fields have on human tissues, especially the bactericidal effect, this investigation aimed to assess their influence on the reduction of oral microorganisms.

Material and Methods

: In order to obtain adequate specimens of dental plaque deposit, microbes such as Streptococcus parasanguinis, Staphylococcus epidermidis, Rhodococcus equi and Candida albicans were isolated from the human mouth. To establish the intensity of microbial growth on the basis of the modified optical density (OD) of agar turbidimetry assay, microbial count and spectrophotometry were applied. The study was carried out with two microbial concentrations (1 and 10 CFU/ml) after periods of incubation of 24 and 48 h and using micromagnets.

Results

: A positive effect of the magnetic field, resulting in the reduction of dental plaque microbes in vitro, was found. In the first 24 hours of exposure to the magnetic field, the number of all isolated microbes was significantly reduced. The most potent influence of magnets and the most intensified reduction after 24 hours were evident in Candida albicans colonies. The decrease in the influence of magnets on microbes in vitro was also detected.

Conclusions

: Magnets reduce the number of microbes and might be recommended as a supplement in therapy for reduced periodontal tissues. This is important because periodontal tissues that are in good conditions provide prolonged support to the oral tissues under partial and supradental denture.  相似文献   
7.
We present a patient with a 33‐year history of poikilodermatous mycosis fungoides (MF) who subsequently developed CD30‐positive large cell transformation. After 6 years of conventional MF treatment, side effects of therapy and/or concomitant diseases prevented the previously applied treatment modalities. The CD30‐directed antibody‐cytotoxic drug conjugate (brentuximab vedotin) was introduced and followed by quick and excellent therapeutic response.  相似文献   
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This review aims to provide an up-to-date knowledge of the psychosocial aspects of egg donation from the perspectives of the egg share donor and their recipient. It explores the motives, experiences and attitudes of egg sharers and their views towards donor anonymity and disclosure. Conclusions are made on how these findings can guide clinical practice and improve egg sharing numbers. A systematic search of peer-reviewed journals of four computerized databases was undertaken. Eleven studies were included in the review. Psychosocial aspects towards donation were positive from the egg share donor and recipient. Concerns raised were whether participating in the egg sharing scheme would impact on their success rates, as well as frustration expressed by a minority regarding the lack of knowledge of egg sharing outside of fertility clinics. The 2005 legislative changes in the UK have not caused the anticipated dramatic decrease in egg donation; however, oocyte donation still falls short of demand. Egg sharing provides a practical option for more patients to access IVF, whilst also providing more donor oocytes. Improved information provision will result in greater awareness of egg sharing, with the potential to recruit more donors and meet the needs of recipients currently on long waiting lists.  相似文献   
10.
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