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31.
32.
Preclinical evaluation of potential infection‐imaging probe [68Ga]Ga‐DOTA‐K‐A9 in sterile and infectious inflammation 下载免费PDF全文
Karin M. Nielsen Nis P. Jørgensen Majbritt H. Kyneb Per Borghammer Rikke L. Meyer Trine R. Thomsen Dirk Bender Svend B. Jensen Ole L. Nielsen Aage K.O. Alstrup 《Journal of labelled compounds & radiopharmaceuticals》2018,61(10):780-795
The development of bacteria‐specific infection radiotracers is of considerable interest to improve diagnostic accuracy and enabling therapy monitoring. The aim of this study was to determine if the previously reported radiolabelled 1,4,7,10‐tetraazacyclododecane‐N,N′,N″,N?‐tetraacetic acid (DOTA) conjugated peptide [68Ga]Ga‐DOTA‐K‐A9 could detect a staphylococcal infection in vivo and distinguish it from aseptic inflammation. An optimized [68Ga]Ga‐DOTA‐K‐A9 synthesis omitting the use of acetone was developed, yielding 93 ± 0.9% radiochemical purity. The in vivo infection binding specificity of [68Ga]Ga‐DOTA‐K‐A9 was evaluated by micro positron emission tomography/magnetic resonance imaging of 15 mice with either subcutaneous Staphylococcus aureus infection or turpentine‐induced inflammation and compared with 2‐deoxy‐2‐[18F]fluoro‐D‐glucose ([18F]FDG). The scans showed that [68Ga]Ga‐DOTA‐K‐A9 accumulated in all the infected mice at injected doses ≥3.6 MBq. However, the tracer was not found to be selective towards infection, since the [68Ga]Ga‐DOTA‐K‐A9 also accumulated in mice with inflammation. In a concurrent in vitro binding evaluation performed with a 5‐carboxytetramethylrhodamine (TAMRA) fluorescence analogue of the peptide, TAMRA‐K‐A9, the microscopy results suggested that TAMRA‐K‐A9 bound to an intracellular epitope and therefore preferentially targeted dead bacteria. Thus, the [68Ga]Ga‐DOTA‐K‐A9 uptake observed in vivo is presumably a combination of local hyperemia, vascular leakiness and/or binding to an epitope present in dead bacteria. 相似文献
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34.
Jess F. Peterson William R. Sukov Beth A. Pitel Stephanie A. Smoley Kathryn E. Pearce Reid G. Meyer Cynthia M. Williamson James B. Smadbeck George Vasmatzis Nicole L. Hoppman Patricia T. Greipp Linda B. Baughn Rhett P. Ketterling 《Genes, chromosomes & cancer》2019,58(8):567-577
The MLLT10 (formerly AF10) gene is the fourth most common KMT2A fusion partner across all acute leukemias and requires at least 3 breaks to form an in‐frame KMT2A/MLLT10 fusion due to the opposite orientation of each gene. A 10‐year retrospective review was performed to identify individuals from all age groups that harbor KMT2A/MLLT10 fusion obtained by our KMT2A/MLLT10 dual‐color dual‐fusion fluorescence in situ hybridization (D‐FISH) assay. Of the 60 unique individuals identified, 31 were male and 29 were female (M:F ratio, 1.1:1) with ages ranging from 3 days to 86 years (mean 21.5 years, median 5.5 years). The diagnoses included acute myeloid leukemia (AML) (49 patients, 82%), B‐ or T‐lymphoblastic leukemia/lymphoma (7 patients, 12%), myeloid sarcoma (3 patients, 5%), and a single case (2%) of undifferentiated leukemia. Twenty‐seven of 49 patients (55%) with AML were in the infant or pediatric age group. Fifty‐three of 60 patients (88%) had KMT2A/MLLT10 D‐FISH signal patterns mostly consisting of single fusions. In addition, 10 (26%) of 38 patients with conventional chromosome studies had “normal” (5 patients) or abnormal (5 patients) chromosome studies that lacked structural or numeric abnormalities involving chromosomes 10 or 11, implying cryptic cytogenetic mechanisms for KMT2A/MLLT10 fusion. Lastly, mate‐pair sequencing was performed on 4 AML cases, 2 of which had “normal” chromosome studies and cryptic KMT2A/MLLT10 fusion as detected by KMT2A/MLLT10 D‐FISH studies, and verified the multiple breaks required to generate KMT2A/MLLT10 fusion. 相似文献
35.
Different in vitro and in vivo tools for elucidating the human metabolism of alpha‐cathinone‐derived drugs of abuse 下载免费PDF全文
Sascha K. Manier Lilian H.J. Richter Jan Schäper Hans H. Maurer Markus R. Meyer 《Drug testing and analysis》2018,10(7):1119-1130
In vitro and in vivo experiments are widely used for studying the metabolism of new psychoactive substances (NPS). The availability of such data is required for toxicological risk assessments and development of urine screening approaches. This study investigated the in vitro metabolism of the 5 pyrrolidinophenone‐derived NPS alpha‐pyrrolidinobutyrophenone (alpha‐PBP), alpha‐pyrrolidinopentiothiophenone (alpha‐PVT), alpha‐pyrrolidinohexanophenone (alpha‐PHP), alpha‐pyrrolidinoenanthophenone (alpha‐PEP, PV8), and alpha‐pyrrolidinooctanophenone (alpha‐POP, PV9). First, they were incubated with pooled human liver microsomes (pHLM) or pooled human liver S9 fraction (pS9) for identification of the main phase I and II metabolites. All substances formed hydroxy metabolites and lactams. Longer alkyl chains resulted in keto group and carboxylic acid formation. Comparing these results with published data obtained using pHLM, primary human hepatocytes (PHH), and authentic human urine samples, PHH provided the most extensive metabolism. Second, enzyme kinetic studies showed that the initial metabolic steps were formed by cytochrome P450 isoforms (CYP) CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 resulting in pyrrolidine, thiophene or alkyl hydroxy metabolites depending on the length of the alkyl chain. The kinetic parameters indicated an increasing affinity of the CYP enzymes with increase of the length of the alkyl chain. These parameters were then used to calculate the contribution of a single CYP enzyme to the in vivo hepatic clearance. CYP2C19 and CYP2D6 were mainly involved in the case of alpha‐PBP and CYP1A2, CYP2C9 and CYP2C19 in the case of alpha‐PVT, alpha‐PHP, alpha‐PEP, and alpha‐POP. 相似文献
36.
Power of Orbitrap‐based LC‐high resolution‐MS/MS for comprehensive drug testing in urine with or without conjugate cleavage or using dried urine spots after on‐spot cleavage in comparison to established LC–MSn or GC–MS procedures 下载免费PDF全文
Reliable, sensitive, and comprehensive urine screening procedures by gas chromatography–mass spectrometry (GC–MS) or liquid chromatography–mass spectrometry (LC–MS) with low or high resolution (HR) are of high importance for drug testing, adherence monitoring, or detection of toxic compounds. Besides conventional urine sampling, dried urine spots are of increasing interest. In the present study, the power of LC–HR–MS/MS was investigated for comprehensive drug testing in urine with or without conjugate cleavage or using dried urine spots after on‐spot cleavage in comparison to established LC–MSn or GC–MS procedures. Authentic human urine samples (n = 103) were split in 4 parts. One aliquot was prepared by precipitation (UP), one by UP with conjugate cleavage (UglucP), one spot on filter paper cards and prepared by on‐spot cleavage followed by liquid extraction (DUSglucE), and one worked‐up by acid hydrolysis, liquid–liquid extraction, and acetylation for GC–MS analysis. The 3 series of LC–HR–MS/MS results were compared among themselves, to corresponding published LC–MSn data, and to screening results obtained by conventional GC–MS. The reference libraries used for the 3 techniques contained over 4500 spectra of parent compounds and their metabolites. The number of all detected hits (770 drug intakes) was set to 100%. The LC–HR–MS/MS approach detected 80% of the hits after UP, 89% after UglucP, and 77% after DUSglucE, which meant over one‐third more hits in comparison to the corresponding published LC–MSn results with ≤49% detected hits. The GC–MS approach identified 56% of all detected hits. In conclusion, LC–HR–MS/MS provided the best screening results after conjugate cleavage and precipitation. 相似文献
37.
Twardella Dorothee Geiss Karla Radespiel-Tröger Martin Benner Axel Ficker Joachim H. Meyer Martin 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2018,61(1):20-31
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Beim Lungenkrebs werden verschiedene histologische Subtypen unterschieden. Im Wesentlichen sind dies das kleinzellige Karzinom,... 相似文献
38.
Eckardt A Meyer A Laas U Hausamen JE 《The British journal of oral & maxillofacial surgery》2007,45(1):11-15
Between March 1982 and December 2002 we did a total of 534 reconstructions with free flaps from various donor sites for 529 patients. The jejunum was the donor site in 181 reconstructions (34%), followed by the radial forearm flap in 173 reconstructions (32%); 86% of the reconstructions were immediately after excisions. Surgical re-exploration was necessary in 37 patients (7%); the failure rate from necrosis of the flap was 5%. Factors associated with complications were American Society of Anesthesiology (ASA) class and age. 相似文献
39.
R. Depprich J. Handschel J. Hornung U. Meyer N. R. Kübler 《Oral and maxillofacial surgery》2007,11(1):19-26
Background
Fractures of the mandible are a common form of facial injury. The aetiological factors associated with mandibular fractures and the trends in these factors over a 10-year period are reported.Methods
A retrospective survey was carried out of 724 patients presenting with a fracture of the mandible over the 10-year-period 1994–2003. Patients` records were reviewed and analyzed according to age, sex, cause of injury, anatomic site of fracture, treatment and postoperative complications.Results
Over the 10-year-period the rate of mandibular fractures remained constant (mean 40,7%). There were no changes in the age group (mean 33,3 years) or in the higher prevalence in male (male-female-ratio 2,3?:?1). The major causes of fractures were assaults (38,6%) and accidental fall (27,3%). The most common fracture site was the condylar region (47,0%) followed by the angle (29,4%). Most fractures were treated by closed reduction until 2002, thereafter surgical treatment increased noticeable. The complication rate was 8,9% and the most common complications were hardware exposure and infection.Conclusion
Fractures of the mandible are a prevalent form of facial injury. Aetiological factors show no significant change over the 10-year-period. Complication-rate is low and will support the tendency towards surgical treatment. 相似文献40.