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31.
L‐asparaginase is an important drug in the treatment of childhood acute lymphoblastic leukaemia (ALL). Cerebrospinal fluid (CSF) asparagine depletion is considered a marker of asparaginase effect in the central nervous system (CNS) and may play a role in CNS‐directed anti‐leukaemia therapy. The objective of this study was to describe CSF asparagine depletion during 30 weeks of pegylated asparaginase therapy, 1000 iu/m2 i.m. every second week, and to correlate CSF asparagine concentration with serum L‐asparaginase enzyme activity. Danish children (1–17 years) with ALL, treated according to the Nordic Society of Paediatric Haematology and Oncology ALL2008 protocol, standard and intermediate risk, were included. CSF samples were obtained throughout L‐asparaginase treatment at every scheduled lumbar puncture. A total of 128 samples from 31 patients were available for analysis. Median CSF asparagine concentration decreased from a pre‐treatment level of 5·3 μmol/l to median levels ≤1·5 μmol/l. However, only 4/31 patients (five samples) had CSF asparagine concentrations below the limit of detection (0·1 μmol/l). In 11 patients, 24 paired same day serum and CSF samples were obtained. A decrease in CSF asparagine corresponded to serum enzyme activities above 50 iu/l. Higher serum enzyme activities were not followed by more extensive depletion. In conclusion, pegylated asparaginase 1000 iu/m2 i.m. every second week effectively reduced CSF asparagine levels.  相似文献   
32.
L‐asparaginase is an important drug in the treatment of childhood acute lymphoblastic leukaemia (ALL). Treatment is associated with several toxicities, including acute pancreatitis. Clinical course, presentation, re‐exposure to L‐asparginase after pancreatitis and risk of recurrent pancreatitis within an asparaginase‐intensive protocol has been poorly reported. Children (1–17 years) on the ongoing Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol with asparaginase‐associated pancreatitis (AAP) diagnosed between 2008 and 2012 were identified through the online NOPHO ALL toxicity registry. NOPHO ALL2008 includes eight or 15 doses of intramuscular pegylated L‐asparginase (PEG‐asparaginase) 1000 iu/m2/dose at 2–6 weeks intervals, with a total of 30 weeks of exposure to PEG‐asparaginase (clinicaltrials.gov no: NCT00819351). Of 786 children, 45 were diagnosed with AAP with a cumulative risk of AAP of 5·9%. AAP occurred after a median of five doses (range 1–13), and 11 d (median) from the latest administration of PEG‐Asparaginase. Thirteen patients developed pseudocysts (30%) and 11 patients developed necrosis (25%). One patient died from pancreatitis. Twelve AAP patients were re‐exposed to L‐asparginase, two of whom developed mild AAP once more, after four and six doses respectively. In conclusion, re‐exposure to PEG‐asparaginase in ALL patients with mild AAP seems safe.  相似文献   
33.
Tourette syndrome (TS) is a childhood onset neurodevelopmental disorder. Although it is widely accepted that genetic factors play a significant role in TS pathogenesis the etiology of this disorder is largely unknown. Identification of rare copy number variations (CNVs) as susceptibility factors in several neuropsychiatric disorders such as attention deficit‐hyperactivity disorder (ADHD), autism and schizophrenia, suggests involvement of these rare structural changes also in TS etiology. In a male patient with TS, ADHD, and OCD (obsessive compulsive disorder) we identified two microduplications (at 15q13.3 and Xq21.31) inherited from a mother with subclinical ADHD. The 15q duplication included the CHRNA7 gene; while two genes, PABPC5 and PCDH11X, were within the Xq duplication. The Xq21.31 duplication was present in three brothers with TS including the proband, but not in an unaffected brother, whereas the 15q duplication was present only in the proband and his mother. The structural variations observed in this family may contribute to the observed symptoms, but further studies are necessary to investigate the possible involvement of the described variations in the TS etiology. © 2013 Wiley Periodicals, Inc.  相似文献   
34.
Objectives - To investigate whether impaired fetal growth, measured by low birth weight and short birth length, is linked with raised levels of serum lipids and increased risk and mortality of coronary heart disease. Design - The association between birth length, birth weight, Ponderal Index and total serum cholesterol was examined in 545 Danish men and women aged 31 to 51 years who participated in the Ebeltoft Health Promotion Project in Denmark. Results - No associations were found in women. For men, a negative association was found between birth weight and serum total cholesterol, with a fall in mean serum total cholesterol from 6.03 mmol/l at birth weight below 3300 g to 5.64 mmol/l at birth weight above 4000. A similar association was found between birth length and serum cholesterol, with a mean value of 6.23 mmol/l at birth length below 51 cm and a mean value of 5.56 mmol/l at birth length above 54 cm. No associations were found for Ponderal Index. Between 3% and 8% of the variance in serum total cholesterol could be explained by the statistical models used in this study. Conclusion - Our findings support the hypothesis of a negative association between birth weight, birth length and elevated serum cholesterol in adult life, but only in men.  相似文献   
35.
We studied the effects of antibiotic prophylaxis, systemically and in bone cement, on the revision rate of cemented total hip arthroplasties (THAs) in data from the Norwegian Arthroplasty Register during the period 1987-2001. To have comparable groups, only THAs performed because of primary osteoarthritis, using cemented implants with documented good results, and high-viscosity cement were included. If systemic antibiotic prophylaxis had been given, only operations with cephalosporin or penicillin were selected. Cox-estimated survival relative revision risks (RR) are presented with adjustment for differences among groups in gender, age, cement brand, type of systemic antibiotic prophylaxis, type of prosthesis, type of operating room, and duration of the operation. Of 22,170 THAs studied, 696 THAs (3.1%) were revised, 440 (2.0%) for aseptic loosening and 102 (0.5%) for deep infection. We found the lowest risk of revision when the antibiotic prophylaxis was given both systemically and in the cement (15,676 THAs). Compared to this combined regime, patients who received antibiotic prophylaxis only systemically (5,960 THAs) had a 1.4 times higher revision rate with all reasons for revision as endpoint (p= 0.001), 1.3 times higher with aseptic loosening (p= 0.02) and 1.8 times higher with infection as the endpoint (p= 0.01). With the combined antibiotic regime, the results were better if antibiotics were given 4 times on the day of surgery (2,194 THAs), as compared to once (1,424 THAs) (p<0.001), twice (2,680 THAs) (p<0.001), or 3 times (5,522 THAs) (p= 0.02). Those who received systemic prophylaxis a single day 1, 2 or 3 times, as compared to 4 times, had a revision rate 1.8-3.5 times higher with all reasons for revision as endpoint, 1.5-3.1 times higher with aseptic loosening, and 2.7-6.8 times higher with infection. When we compared systemic prophylaxis 4 times in 1 day, no further improvement resulted in those given systemic prophylaxis for 2 days (1,928 THAs) or 3 days (717 THAs). In a subset of data including only the Charnley prosthesis, we obtained similar results. This observational study shows that the best results were recorded when antibiotic prophylaxis was given both systemically and in the bone cement, and if the systemic antibiotic was given 4 times on the day of surgery.  相似文献   
36.
37.
Treatment of patients with concurrent mental illness and substance abuse represents a challenge to the traditional treatment systems. This article gives: 1) an introduction of the concept and frequency of dual diagnosis (DD), 2) a presentation and discussion of the latest guidelines on DD treatment, 3) status on the current situation in the DD field in Denmark, and 4) potentials for future research. The article is based on systematic examination of evidence-based research and popularized latest guidelines on DD treatment. Methodologically, both treatment and research is challenged by the diversity in DD combinations. Although integrated treatment with the inclusion of cognitive–behavioural therapy, motivational interviewing and family intervention in DD treatment show promising results, it remains to establish which treatment programme is the most qualified in improving mental health and reducing substance use. A future priority is the development of DD treatment that targets specific co-morbid combinations and treatment needs.  相似文献   
38.
Penicillin G is frequently used to treat infective endocarditis (IE) caused by streptococci, penicillin‐susceptible staphylococci and enterococci. Appropriate antibiotic exposure is essential for survival and reduces the risk of complications and drug resistance development. We determined penicillin G plasma concentration [p‐penicillin] once weekly in 46 IE patients. The aim was to evaluate whether penicillin G 3 g every 6 hr (q6 h) resulted in therapeutic concentrations and to analyse potential factors that influence inter‐ and intra‐individual variability, using linear regression and a random coefficient model. [P‐penicillin] at 3 hr and at 6 hr was compared with the minimal inhibitory concentration (MIC) of the bacteria isolated from blood cultures to evaluate the following PK/PD targets: 50% fT > MIC and 100% fT > MIC. [P‐penicillin] varied notably between patients and was associated with age, weight, p‐creatinine and estimated creatinine clearance (eCLcr). Additionally, an increase in [p‐penicillin] during the treatment period showed strong correlation with age, a low eCLcr, a low weight and a low p‐albumin. Of the 46 patients, 96% had [p‐penicillin] that resulted in 50% fT > MIC, while 71% had [p‐penicillin] resulting in 100% fT > MIC. The majority of patients not achieving the 100% fT > MIC target were infected with enterococci. Streptococci and staphylococci isolated from blood cultures were highly susceptible to penicillin G. Our results suggest that penicillin G 3 g q6 h is suitable to treat IE caused by streptococci and penicillin‐susceptible staphylococci, but caution must be taken when the infection is caused by enterococci. When treating enterococci, therapeutic drug monitoring should be applied to optimize penicillin G dosing and exposure.  相似文献   
39.
40.

Purpose

The purpose of this study was to assess the effect of several chemical permeation enhancers on the buccal permeability of nicotine and to image the spatial distribution of nicotine in buccal mucosa with and without buccal permeation enhancers.

Methods

The impact of sodium taurodeoxycholate (STDC), sodium dodecyl sulphate (SDS), dimethyl sulfoxide (DMSO) and Azone® on the permeability of [3H]-nicotine and [14C]-mannitol (a paracellular marker) across porcine buccal mucosa was studied ex vivo in modified Ussing chambers. The distribution of nicotine, mannitol and permeation enhancers was imaged using using matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MSI).

Results

Despite STDC significantly increasing permeability of [14C]-mannitol, no enhancing effect was seen on [3H]-nicotine permeability with any of the permeation enhancers. Rather, SDS and DMSO retarded nicotine permeability, likely due to nicotine being retained in the donor compartment. The permeability results were complemented by the spatial distribution of nicotine and mannitol determined with MALDI MSI.

Conclusions

The buccal permeability of nicotine was affected in an enhancer specific manner, suggesting that nicotine primarily diffuses via the transcellular pathway. MALDI MSI was shown to complement ex vivo permeability studies and to be a useful qualitative tool for visualizing drug and penetration enhancer distribution in buccal mucosa.
  相似文献   
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