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2.
Int J Tuberc Lung Dis ; 22(3): 309-320, 2018 03 01.
Article in English | MEDLINE | ID: mdl-29471910

ABSTRACT

BACKGROUND: The effect of quality improvement measures on the performance of diagnostic tuberculosis (TB) laboratories in low- and lower-middle-income countries is not known, and is the subject of this review. METHODS: Three databases were searched for quality improvement studies presenting data on performance parameters before and after the implementation of quality improvement interventions. RESULTS: Twenty-one studies were included in this review. Quality improvement measures were most frequently implemented by an external organization; settings targeted ranged from microscopy centers, hospitals, districts, regional and national reference laboratories. Quality improvement interventions and outcome measurements were highly heterogeneous. Most studies investigated interventions aimed at improving smear microscopy (n = 17). Two studies evaluated comprehensive quality improvement measures (n = 2) and another three studies focused on mycobacterial culture and drug susceptibility testing. Most studies showed an improvement in outcomes measured on before-after or time trend analysis. CONCLUSION: Quality improvement measures implemented in TB laboratories showed a positive impact on various outcomes. Due to the high heterogeneity of outcome reporting and interventions and the low quality of the studies, the effect size was not clear. Identification of standardized quality indicators and their link to the quality of patient care would improve knowledge in this field.


Subject(s)
Outcome Assessment, Health Care/standards , Quality Improvement/standards , Tuberculosis/diagnosis , Developing Countries , Humans , Laboratories , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects , Randomized Controlled Trials as Topic
3.
Article in English | MEDLINE | ID: mdl-27354779

ABSTRACT

Osteoporosis is more common in patients with COPD and in smokers. The aim of this study was to assess whether measures of emphysema and airway disease on computed tomography (CT) were associated with lower bone density or vertebral fractures in smokers with and without COPD. For this purpose, we included participants from the NELSON lung cancer screening trial. Bone density was measured as Hounsfield Units in the first lumbar vertebra, and vertebral fractures were assessed semiquantitatively. The 15th percentile method (Perc15) was used to assess emphysema, and the airway lumen perimeter (Pi10) was used for airway wall thickness. Expiratory/inspiratory-ratiomean lung density (E/I-ratioMLD) was used as a measure for air trapping and tracheal index to assess tracheal deformity. Linear regression models and logistic regression models were used to assess associations between CT biomarkers, bone density, and presence of fractures. Exactly 1,093 male participants were eligible for analysis. Lower Perc15 and higher E/I-ratioMLD were significantly associated with lower bone density (b=-1.27, P=0.02 and b=-0.37, P=0.02, respectively). Pi10 and tracheal index were not associated with bone density changes. CT-derived biomarkers were not associated with fracture prevalence. Bone density is lower with increasing extent of emphysema and small airway disease but is not associated with large airway disease and tracheal deformity. This may indicate the necessity to measure bone density early in smokers with emphysema and air trapping to prevent vertebral fractures.


Subject(s)
Bone Density , Lumbar Vertebrae/diagnostic imaging , Osteoporosis/diagnostic imaging , Osteoporotic Fractures/diagnostic imaging , Pulmonary Disease, Chronic Obstructive/etiology , Pulmonary Emphysema/etiology , Smoking/adverse effects , Spinal Fractures/diagnostic imaging , Tomography, X-Ray Computed , Aged , Belgium , Disease Progression , Humans , Linear Models , Logistic Models , Lumbar Vertebrae/injuries , Lumbar Vertebrae/physiopathology , Lung/physiopathology , Male , Middle Aged , Netherlands , Odds Ratio , Osteoporosis/etiology , Osteoporosis/physiopathology , Osteoporotic Fractures/etiology , Osteoporotic Fractures/physiopathology , Predictive Value of Tests , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Emphysema/diagnosis , Pulmonary Emphysema/physiopathology , Risk Factors , Severity of Illness Index , Spinal Fractures/etiology , Spinal Fractures/physiopathology
4.
Eur Radiol ; 26(9): 3046-53, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26801161

ABSTRACT

OBJECTIVE: To determine inter-observer and inter-examination variability of manual attenuation measurements of the vertebrae in low-dose unenhanced chest computed tomography (CT). METHODS: Three hundred and sixty-seven lung cancer screening trial participants who underwent baseline and repeat unenhanced low-dose CT after 3 months because of an indeterminate lung nodule were included. The CT attenuation value of the first lumbar vertebrae (L1) was measured in all CTs by one observer to obtain inter-examination reliability. Six observers performed measurements in 100 randomly selected CTs to determine agreement with limits of agreement and Bland-Altman plots and reliability with intraclass correlation coefficients (ICCs). Reclassification analyses were performed using a threshold of 110 HU to define osteoporosis. RESULTS: Inter-examination reliability was excellent with an ICC of 0.92 (p < 0.001). Inter-examination limits of agreement ranged from -26 to 28 HU with a mean difference of 1 ± 14 HU. Inter-observer reliability ICCs ranged from 0.70 to 0.91. Inter-examination variability led to 11.2 % reclassification of participants and inter-observer variability led to 22.1 % reclassification. CONCLUSIONS: Vertebral attenuation values can be manually quantified with good to excellent inter-examination and inter-observer reliability on unenhanced low-dose chest CT. This information is valuable for early detection of osteoporosis on low-dose chest CT. KEY POINTS: • Vertebral attenuation values can be manually quantified on low-dose unenhanced CT reliably. • Vertebral attenuation measurements may be helpful in detecting subclinical low bone density. • This could become of importance in the detection of osteoporosis.


Subject(s)
Lumbar Vertebrae/physiology , Lung Neoplasms/diagnostic imaging , Osteoporosis/diagnostic imaging , Aged , Early Detection of Cancer , Female , Humans , Lumbar Vertebrae/radiation effects , Male , Middle Aged , Observer Variation , Radiation Dosage , Reproducibility of Results , Retrospective Studies , Tomography, X-Ray Computed/methods
5.
J Bone Miner Res ; 29(10): 2224-9, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24715549

ABSTRACT

We studied the vertebral fracture prevalence on low-dose chest computed tomography (CT) in male lung cancer screening participants and the association of fractures and bone density with chronic obstructive pulmonary disease (COPD) and smoking. 1140 male current and former smokers with ≥ 16.5 packyears from the NELSON lung cancer screening trial were included. Age, body mass index, and smoking status were registered. CT scans and pulmonary function tests were obtained on the same day. On CT, vertebral fractures and bone density were measured. The cohort had a mean age of 62.5 years (standard deviation 5.2) old; 531 (46.6%) had quit smoking; and 437 (38.3%) had COPD. Of the group, 100 (8.8%) participants had a vertebral fracture. Fracture prevalence was higher in current compared to former smokers (11.3% versus 5.8%, p = 0.001), but similar in participants with COPD compared to those without (9.6% versus 8.3%, p = 0.430). The multivariable adjusted odds ratio for fracture presence was 1.79 (95% CI: 1.13-2.84) in current smokers and 1.08 (95% CI: 0.69-1.67) in COPD participants. Bone density was lower in current compared to former smokers (103.2 HU versus 108.7 HU, p = 0.006) and in participants with COPD compared to those without [100.7 Hounsfield Units (HU) versus 108.9 HU, p < 0.001]. In multivariate analysis, smoking status and COPD status were independently associated with bone density, corrected for age and body mass index. In conclusion, our study shows that lung cancer screening participants have a substantial vertebral fracture burden. Fractures are more common in current smokers, who also have lower bone density. We could not confirm that COPD is independently associated with vertebral fractures.


Subject(s)
Bone Density , Early Detection of Cancer , Lung Neoplasms/diagnosis , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/physiopathology , Smoking/adverse effects , Spinal Fractures/physiopathology , Humans , Lung Neoplasms/complications , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/physiopathology , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/diagnostic imaging , Spinal Fractures/complications , Spinal Fractures/diagnostic imaging , Tomography, X-Ray Computed
6.
Otolaryngol Head Neck Surg ; 150(3): 359-64, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24567340

ABSTRACT

OBJECTIVE: To assess the diagnostic value of nasal endoscopic findings in adults suspected of chronic rhinosinusitis. DATA SOURCES: PubMed, EMBASE, and the Cochrane Library. REVIEW METHODS: A comprehensive search was performed up to March 5, 2013. Articles that assessed the diagnostic value of nasal endoscopy in adults suspected of chronic rhinosinusitis were included. For selected articles, the study design was assessed for directness of evidence and risk of bias. Prevalence, positive, and negative predictive values were extracted from reported data. RESULTS: Out of 3899 unique publications, we included 3 diagnostic studies with a high directness of evidence and a low or moderate risk of bias for data extraction. They showed a prevalence of chronic rhinosinusitis (diagnosed with computed tomography) of .40 to .56. Compared with posterior probabilities we found an added value for ruling in chronic rhinosinusitis by a positive nasal endoscopy of 25% to 28% and an added value for ruling out chronic rhinosinusitis by a negative nasal endoscopy of 5% to 30%. CONCLUSION AND RECOMMENDATION: Computed tomography is not considered necessary in case of a positive nasal endoscopy. While nasal endoscopy cannot rule out chronic rhinosinusitis, we advise computed tomography only for patients with a prolonged or complicated course of rhinosinusitis.


Subject(s)
Endoscopy/methods , Practice Guidelines as Topic , Rhinitis/diagnosis , Sinusitis/diagnosis , Adult , Chronic Disease , Humans , Nose
7.
Diabetologia ; 56(8): 1826-34, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23653049

ABSTRACT

AIMS/HYPOTHESIS: In vitro, insulin glargine (A21Gly,B31Arg,B32Arg human insulin) has an insulin receptor (IR) profile similar to that of human insulin, but a slightly higher affinity for the IGF-1 receptor (IGF1R). AspB10 human insulin (AspB10), [corrected] the only insulin analogue with proven carcinogenic activity, has a greater affinity for IGF1R and IR, and a prolonged IR occupancy time. The pharmacological and signalling profile of therapeutic and suprapharmacological doses of glargine were analysed in different tissues of rats, and compared with human insulin and AspB10. METHODS: Male Wistar rats were injected s.c. with human insulin or insulin analogue at doses of 1 to 200 U/kg, and the effects on blood glucose and the phosphorylation status of IR, IGF1R, Akt and extracellular signal-regulated protein kinase 1/2 in muscle, fat, liver and heart samples were investigated. RESULTS: Glargine, AspB10 and human insulin lowered blood glucose, with the onset of action delayed with glargine. Glargine treatment resulted in phosphorylation levels of IR and Akt that were comparable with those achieved with human insulin, although delayed in time in some tissues. AspB10 treatment resulted in at least twofold higher phosphorylation levels and significantly longer duration of IR and Akt phosphorylation in most tissues. None of the insulin treatments resulted in detectable IGF1R phosphorylation in muscle or heart tissue, whereas intravenous injection of IGF-1 increased IGF1R phosphorylation. CONCLUSIONS/INTERPRETATION: The IR signalling pattern of AspB10 in vivo is distinctly different from that of human insulin and insulin glargine, and might challenge the notion that activation of IGF1R plays a role in the observed carcinogenic effect of AspB10.


Subject(s)
Insulin Aspart/pharmacology , Insulin, Long-Acting/pharmacology , Animals , Blood Glucose/drug effects , Humans , Insulin/analogs & derivatives , Insulin/pharmacology , Insulin Glargine , Male , Phosphorylation/drug effects , Rats , Rats, Wistar , Receptor, Insulin/metabolism
8.
Pathologe ; 34(4): 335-7, 2013 Jul.
Article in German | MEDLINE | ID: mdl-23436120

ABSTRACT

Maxillary ameloblastomas can extensively expand into the paranasal sinuses or even the nasal cavity due to a slow growth pattern. Sinusitis is rarely the first tumor-related complaint. Due to the various growth forms of ameloblastomas the challenging histological differential diagnosis includes several other odontogenic as well as benign and malignant non-odontogenic tumors, e.g. tumors from the mucosa of the paranasal sinuses, salivary glands and Rathke's pouch. Despite the radical surgical approach a complete resection with wide margins cannot always be achieved. Maxillary ameloblastomas show the highest recurrence rates.


Subject(s)
Ameloblastoma/pathology , Ethmoid Sinus/pathology , Maxillary Neoplasms/pathology , Maxillary Sinus Neoplasms/pathology , Nose Neoplasms/pathology , Paranasal Sinus Neoplasms/pathology , Adult , Ameloblastoma/surgery , Endoscopy , Ethmoid Sinus/surgery , Follow-Up Studies , Humans , Male , Maxilla/pathology , Maxilla/surgery , Maxillary Neoplasms/surgery , Maxillary Sinus Neoplasms/surgery , Nasal Cavity/pathology , Neoplasm Invasiveness , Nose Neoplasms/surgery , Olfaction Disorders/etiology , Paranasal Sinus Neoplasms/surgery , Radiography, Panoramic , Sinusitis/etiology , Sinusitis/surgery , Tomography, X-Ray Computed
9.
Diabetes Obes Metab ; 15(4): 324-34, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23121319

ABSTRACT

AIMS: Intensive glycaemic control in type 2 diabetes achieved by insulin is generally accompanied by body weight gain. This study was performed to emphasize the meaning of caloric analysis of urine and faeces for energy balance. METHODS: We measured energetic loss via urine and faeces during antihyperglycaemic treatment in male obese Zucker diabetic fatty (ZDF) rats. Rats were treated for 10 days with the sodium-glucose-linked transporter-2 (SGLT2) inhibitor AVE2268, with insulin glargine, with the GLP-1 receptor agonist lixisenatide and with the combination of insulin glargine and lixisenatide. Each study was accompanied by one lean (Fa/?) and one obese (fa/fa) untreated non-diabetic and diabetic control group, respectively. Blood glucose, body weight alterations and food assimilation efficiency were monitored. RESULTS: In control ZDF rats, more than 12 g/day of pure glucose was urinarily excreted. In total, the energetic loss via urine exceeded 30% from total energy uptake. Insulin glargine treatment decreased urinary energetic loss, leading to a body weight gain of approximately 3 g/day. An almost body weight-neutral antihyperglycaemic treatment could be achieved with AVE2268 and lixisenatide. While lixisenatide reduced body weight gain via reduction of energy uptake, the SGLT2 inhibitor even increased urinary glucose and thus energy excretion. Combining insulin glargine with lixisenatide attenuated the anabolic effect of insulin resulting in weight neutrality. CONCLUSIONS: Our data clearly show renal contribution to the body's energy control by urinary glucose excretion (UGE) during antidiabetic treatment. The undesired retained energy could be reduced via additional UGE or via simultaneous reduction of energy uptake and/or energy retention.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Glucosides/pharmacology , Hypoglycemic Agents/pharmacology , Insulin, Long-Acting/pharmacology , Peptides/pharmacology , Animals , Blood Glucose/drug effects , Glucagon-Like Peptide-1 Receptor , Glycated Hemoglobin/drug effects , Insulin Glargine , Kidney/drug effects , Male , Rats , Rats, Zucker , Receptors, Glucagon/agonists , Sodium-Glucose Transporter 2 , Sodium-Glucose Transporter 2 Inhibitors , Weight Gain/drug effects
10.
Water Res ; 43(17): 4225-37, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19577270

ABSTRACT

Anaerobic sewer biofilm is a composite of many different microbial populations, including sulfate reducing bacteria (SRB), methanogens and heterotrophic bacteria. Nitrate addition to sewers in an attempt to control hydrogen sulfide concentrations affects the behaviour of these populations, which in turn impacts on wastewater characteristics. Experiments were carried out on a laboratory reactor system simulating a rising main to determine the impact of nitrate addition on the microbial activities of anaerobic sewer biofilm. Nitrate was added to the start of the rising main during sewage pump cycles at a concentration of 30 mg-N L(-1) for over 5 months. While it reduced sulfide levels at the outlet of the system by 66%, nitrate was not toxic or inhibitory to SRB activity and did not affect the dominant SRB populations in the biofilm. Long-term nitrate addition in fact stimulated additional SRB activity in downstream biofilm. Nitrate addition also stimulated the activity of nitrate reducing, sulfide oxidizing bacteria that appeared to be primarily responsible for the prevention of sulfide build up in the wastewater in the presence of nitrate. A short adaptation period of three to four nitrate exposure events (approximately 10 h) was required to stimulate biological sulfide oxidation, beyond which no sulfide accumulation was observed under anoxic conditions. Nitrate addition effectively controlled methane concentrations in the wastewater. The nitrate uptake rate of the biofilm increased with repeated exposure to nitrate, which in turn increased the consumption of biodegradable COD in the wastewater. These results provide a comprehensive understanding of the impact of nitrate addition on wastewater composition and sewer biofilm microbial activities, which will facilitate optimization of nitrate dosing for effective sulfide control in rising main sewers.


Subject(s)
Biofilms , Nitrates/chemistry , Sewage , Anaerobiosis , Biosensing Techniques , Electrophoresis, Polyacrylamide Gel , Oxidation-Reduction
11.
J Clin Immunol ; 29(4): 545-54, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19353249

ABSTRACT

PURPOSE: The major histocompatibility complex class I related A (MICA) and MICB molecules are ligands of NKG2D receptors on natural killer cells, gamma/delta T cells, and CD8ass T cells that mediate host antitumor immune response. The role of MICA-TM and MICB C1_2_A alleles in patients with colorectal cancer has not yet been investigated. METHODS: We have analyzed the MICA-TM and MICB C1_2_A polymorphisms in colorectal cancer patients (n = 79) by polymerase chain reaction amplification, subsequent electrophoresis, and sequencing in comparison to a previously analyzed cohort of healthy controls (n = 306). Allele frequencies obtained for MICA-TM and MICB C1_2_A were compared to histopathological data regarding tumor invasion, disease progression, microsatellite instability, and the presence of KRAS mutations (codon 12) and analyzed for possible impact on tumor-related survival (n = 61). RESULTS: Allele frequencies of MICA-TM and MICB C1_2_A polymorphisms were not different in patients with colorectal cancer in comparison to normal controls. In colorectal cancer patients, MICA-TM A4 allele was directly and MICA-TM A5 allele was inversely associated with lymph node involvement and advanced UICC stages. Tumor-related survival in colorectal cancer patients was significantly reduced in the presence of the MICA-TM A4 allele (p = 0.015). In patients with microsatellite stable tumors, survival was reduced in association with the MICA-TM A4 allele (p = 0.006) and MICA-TM A9 allele (p = 0.034), but increased in patients showing the MICA-TM A5 allele (p = 0.042). CONCLUSIONS: Specific MICA-TM alleles seem to influence tumor progression and midterm survival of patients with colorectal cancer, indicating an important role of host innate immune predisposition involving NKG2D mediated antitumor response.


Subject(s)
Colorectal Neoplasms/genetics , Histocompatibility Antigens Class I/genetics , Microsatellite Repeats/genetics , Proto-Oncogene Proteins/genetics , ras Proteins/genetics , Adult , Aged , Aged, 80 and over , Alleles , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Female , Gene Frequency , Genotype , Histocompatibility Antigens Class I/immunology , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Mutation/genetics , Polymorphism, Genetic , Proto-Oncogene Proteins/immunology , Proto-Oncogene Proteins p21(ras) , ras Proteins/immunology
12.
Eur J Clin Pharmacol ; 65(8): 783-8, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19319511

ABSTRACT

PURPOSE: Anticoagulation therapy with coumarins necessitates a strict individualization of dosing. Whereas the impacts of the cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase (VKORC1) polymorphisms on warfarin dosing are clearly established, the role of these genetic variants on dosing and the safe use of phenprocoumon are less well investigated and, to a certain degree, controversial. METHODS: We studied the most frequent functional polymorphisms of VKORC1, CYP2C9, and CYP3A5 in 60 consecutive patients demonstrating complicated phenprocoumon-mediated anticoagulation and in 120 controls. RESULTS: The frequencies of the less active VKORC1 haplotype A-group alleles (p < 0.0001) and of CYP2C9 genotypes with two variant alleles (p = 0.035) were higher in the patient cohort than in the control group, while the frequency of patients carrying only one variant CYP2C9 allele was unchanged relative to the control subjects (RR 1.2; p = 0.49). CONCLUSION: The data suggest a fundamental role of VKORC1 haplotypes and a minor role of CYP2C9 variants in the anticoagulation property of phenprocoumon.


Subject(s)
Anticoagulants/administration & dosage , Anticoagulants/pharmacokinetics , Aryl Hydrocarbon Hydroxylases/genetics , Cytochrome P-450 CYP3A/genetics , Mixed Function Oxygenases/genetics , Phenprocoumon/administration & dosage , Phenprocoumon/pharmacokinetics , Polymorphism, Genetic , White People/genetics , Administration, Oral , Aged , Aged, 80 and over , Cytochrome P-450 CYP2C9 , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Gene Frequency , Genotype , Germany , Haplotypes , Humans , Male , Middle Aged , Vitamin K Epoxide Reductases
13.
Clin Pharmacol Ther ; 85(3): 269-72, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19037197

ABSTRACT

After administration of metoprolol, plasma concentrations of the drug are markedly higher in CYP2D6 poor metabolizers (PMs) than in non-PMs. In a prospective double-blind 3-month study, we investigated whether this translates into differences in metoprolol's effects after initiation of therapy. Despite administering equal doses to PMs and non-PMs, metoprolol plasma concentrations were 4.9-fold higher in the PM group. Metoprolol evoked significantly and persistently greater reductions in heart rate, diastolic blood pressure, and mean arterial pressure in PMs than in non-PMs. It appears, therefore, that the CYP2D6 genotype contributes to interindividual differences in metoprolol response.


Subject(s)
Cytochrome P-450 CYP2D6/genetics , Metoprolol/therapeutic use , Adult , Aged , Blood Pressure/drug effects , Blood Pressure/genetics , Double-Blind Method , Female , Genotype , Heart Rate/drug effects , Heart Rate/genetics , Humans , Longitudinal Studies , Male , Metoprolol/pharmacology , Middle Aged , Polymorphism, Genetic/drug effects , Prospective Studies
15.
Horm Metab Res ; 40(3): 172-80, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18348079

ABSTRACT

We recently showed that insulin analogues exhibit a beta-cell protective function. The aim of this study was to test if the anti-apoptotic activity of GLP-1 agonists and insulin analogues is mediated by different pathways and if combined treatment may provide augmented protection against beta-cell death. Incubation of INS-1 cells with cytokines or fatty acids increased the number of apoptotic cells and caspase 3 activity, which was reduced by pretreatment with GLP-1 and its receptor agonists exendin-4 and AVE0010 by 50-60%. Similar effects (about 40% reduction) were observed after pretreatment with several insulin analogues. Combined treatment revealed additive activity and resulted in prevention of both cytokine- and fatty acid-induced apoptosis by up to 80%. No acute Akt-phosphorylation in response to GLP-1 receptor agonists could be observed, however, it became detectable after 24-hour stimulation. Gene silencing of Akt2 increased cytokine-induced apoptosis 2-fold. Under these conditions the beta-cell protective activity of AVE0010 remained completely unaltered. We show here that the anti-apoptotic activity of GLP-1 and its receptor agonists AVE0010 and exendin-4 is enhanced by addition of insulin analogues and that the anti-apoptotic action of GLP-1 mimetics is mostly unrelated to Akt2 signaling. It is suggested that combination of GLP-1 receptor agonists and insulin analogues, specifically insulin glargine, may represent a new therapeutic option for preservation of beta-cell mass in type 2 diabetic patients.


Subject(s)
Apoptosis/drug effects , Fatty Acids, Nonesterified/pharmacology , Insulin-Secreting Cells/metabolism , Insulin/analogs & derivatives , Interferon-gamma/pharmacology , Interleukin-1beta/pharmacology , Peptides/pharmacology , Receptors, Glucagon/agonists , Venoms/pharmacology , Animals , Antiviral Agents/pharmacology , Apoptosis/physiology , Blotting, Western , Caspases/metabolism , Cells, Cultured , Cyclic AMP/metabolism , Drug Therapy, Combination , Exenatide , Gene Silencing , Glucagon-Like Peptide-1 Receptor , Hypoglycemic Agents/pharmacology , Insulin/pharmacology , Insulin Glargine , Insulin, Long-Acting , Phosphorylation , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA, Small Interfering , Rats , Receptors, Glucagon/metabolism
16.
Mycotoxin Res ; 23(2): 68-72, 2007 Jun.
Article in English | MEDLINE | ID: mdl-23605909

ABSTRACT

Plants have a high capacity to transform and thereby detoxify deleterious or poisonous compounds, like mycotoxins. The formation of glucose conjugates has a central role in this process. Mammals, however, are able to (partly) release the precursor substances during digestion, reactivating the mycotoxins. This short review provides a brief summary about the metabolism of theFusarium mycotoxins deoxynivalenol and zearalenone in plants. Two examples are discussed in greater detail. First, the formation of deoxynivalenol-3-glucoside in wheat is linked to a quantitative trait locus that is often used forFusarium head blight resistance breeding. Secondly, the metabolism of zearalenone inArabidopsis thaliana results in at least 17 different metabolites, all of which are potentially hazardous for humans and animals.

17.
Food Addit Contam ; 23(11): 1194-200, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17071522

ABSTRACT

The biotransformation products of zearalenone, a Fusarium mycotoxin, were elucidated using the model plant Arabidopsis thaliana. After treatment of plant seedlings with 50 microM zearalenone, both the liquid media and the plant extracts were analysed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). An array of 17 different metabolites, most prominently glucosides, malonylglucosides, di-hexose- and hexose-pentose disaccharides of zearalenone, and alpha- and beta-zearalenol, were detected in the samples. Time courses for the different zearalenone metabolites were recorded and they give a closer insight into the metabolism kinetics. A scheme proposing the zearalenone metabolism in A. thaliana is given. The aspect of food safety regarding the (potential) occurrence of masked mycotoxins in agricultural commodities is discussed.


Subject(s)
Arabidopsis/chemistry , Mycotoxins/analysis , Zearalenone/analysis , Chromatography, Liquid , Tandem Mass Spectrometry
18.
Int J Clin Pharmacol Ther ; 44(9): 397-400, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16995327

ABSTRACT

OBJECTIVE: We reported recently that celecoxib inhibits the metabolism of the cytochrome P450 (CYP)2D6 substrate metoprolol in volunteers. Valdecoxib, the active metabolite of parecoxib, has also been claimed to interfere with the metabolism of CYP2D6 substrates. However, little support for this contention is available despite the intensive use of parecoxib in the perioperative setting. Therefore, the objective of this study was to examine the effect of valdecoxib on the pharmacokinetics of the clinically relevant CYP2D6 substrate metoprolol. METHODS: An open, randomized, 3-period crossover study was performed in 15 healthy male volunteers. Metoprolol (50 mg) was given in all 3 periods without, or following a 7-day pre-treatment with valdecoxib (20 mg, o.d.) or rofecoxib (25 mg, o.d.), to achieve steady state conditions of COX-2 inhibitors in Periods 2 and 3. In a small group of extensive metabolizers (EM/EM), short-term application of twice the dose was investigated. RESULTS: No effect of valdecoxib (20 mg/d) or rofecoxib (25 mg/d) were detected on the area under the plasma concentration-time curve of metoprolol (323 +/- 333 to 324 +/- 296 or 309 +/- 256 microg x h/l) or at a higher dose. No significant changes of pharmacokinetic or pharmacodynamic parameters of metoprolol were apparent. CONCLUSION: We conclude that, at therapeutic doses, valdecoxib and rofecoxib do not influence the CYP2D6 substrate metoprolol.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cyclooxygenase 2 Inhibitors/pharmacology , Cytochrome P-450 CYP2D6/metabolism , Isoxazoles/pharmacology , Metoprolol/pharmacokinetics , Sulfonamides/pharmacology , Adult , Cross-Over Studies , Cytochrome P-450 CYP2D6/genetics , Humans , Lactones/pharmacology , Male , Metoprolol/blood , Prodrugs/pharmacology , Sulfones/pharmacology
19.
Chemosphere ; 54(8): 1135-44, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14664843

ABSTRACT

A computer simulation of the environmental concentrations of some typical consumer-product ingredients was performed using the geo-referenced exposure model GREAT-ER (Geo-referenced Regional Environmental Assessment Tool for European Rivers) in the river Itter. Boron and LAS were chosen as typical detergent ingredients along with EDTA, NTA and Triclosan as examples of household and cosmetic product ingredients. The simulations were based on consumption figures of the respective chemical in consumer products in the year 2000. For EDTA, the consumption figure used for the calculation had to be extended to commercial products since the EDTA-use in domestic products could not account for the measured concentrations alone. The resulting PEC (Predicted Environmental Concentration) for all investigated compounds showed very good accordance to the measured concentrations in the Itter which were monitored in the same year. The concentrations did not deviate more than by a factor of 3. GREAT-ER's calculated 90th-percentile was never exceeded by the monitoring result thus reflecting a reasonable accuracy.


Subject(s)
Environmental Monitoring/methods , Household Products/analysis , Rivers , Water Pollutants, Chemical/analysis , Arylsulfonates/analysis , Arylsulfonates/chemistry , Boron/analysis , Computer Simulation , Databases, Factual , Edetic Acid/analysis , Germany , Models, Theoretical , Nitrilotriacetic Acid/analogs & derivatives , Nitrilotriacetic Acid/analysis , Sensitivity and Specificity , Triclosan/analysis
20.
Clin Genet ; 64(4): 339-49, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12974739

ABSTRACT

Defects in nine sarcomeric protein genes are known to cause hypertrophic cardiomyopathy (HCM). Mutation types and frequencies in large cohorts of consecutive and unrelated patients have not yet been determined. We, therefore, screened HCM patients for mutations in six sarcomeric genes: myosin-binding protein C3 (MYBPC3), MYH7, cardiac troponin T (TNNT2), alpha-tropomyosin (TPM1), cardiac troponin I (TNNI3), and cardiac troponin C (TNNC1). HCM was diagnosed in 108 consecutive patients by echocardiography (septum >15 mm, septal/posterior wall >1.3 mm), angiography, or based on a state after myectomy. Single-strand conformation polymorphism analysis was used for mutation screening, followed by DNA-sequencing. A total of 34 different mutations were identified in 108 patients: 18 mutations in MYBPC3 in 20 patients [intervening sequence (intron) 7 + 1G > A and Q1233X were found twice], 13 missense mutations in MYH7 in 14 patients (R807H was found twice), and one amino acid change in TPM1, TNNT2, and TNNI3, respectively. No disease-causing mutation was found in TNNC1. Cosegregation with the HCM phenotype could be demonstrated for 13 mutations (eight mutations in MYBPC3 and five mutations in MYH7). Twenty-eight of the 37 mutation carriers (76%) reported a positive family history with at least one affected first-grade relative; only eight mutations occurred sporadically (22%). MYBPC3 was the gene that most frequently caused HCM in our population. Systematic mutation screening in large samples of HCM patients leads to a genetic diagnosis in about 30% of unrelated index patients and in about 57% of patients with a positive family history.


Subject(s)
Cardiomyopathy, Hypertrophic/genetics , Carrier Proteins/genetics , Genetic Testing , Mutation/genetics , Sarcomeres/genetics , Troponin/genetics , Adult , Aged , Cardiomyopathy, Hypertrophic/diagnosis , Chromosome Mapping , Cohort Studies , Female , Gene Components , Humans , Male , Middle Aged , Pedigree , Polymorphism, Single-Stranded Conformational , Sequence Analysis, DNA
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