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Jennifer LaRusso Franziska Ringpfeil Jouni Uitto 《CTS Clinical and Translational Science》2010,3(6):295-298
Pseudoxanthoma elasticum (PXE), an autosomal recessive multisystem disorder, is caused by mutations in the ABCC6 gene, and approximately 300 distinct mutations representing >1,000 mutant alleles have been disclosed thus far. Few population‐based studies have reported mutational hotspots in some geographic areas. In this study, we attempted to correlate recurring mutations with the individuals’ ethnic origin. Specifically, we plotted our international database of 70 families from distinct or mixed ethnic backgrounds against their mutations. The frequent p.R1141X mutation was distributed widely across Europe, while deletion of exons 23–29 (del23–29) was encountered in Northern Europe and in Northern Mediterranean countries. p.R1138W may be a marker for French descent, evidenced by its presence also in French Canadians. The splice site transition mutation 3736–1G→A was seen in the neighboring countries Greece and Turkey, whereas 2542 delG occurs only in the Japanese. Two mutations seem to be present worldwide without evidence of a founder effect, p.Q378X and p.R1339C, suggesting the presence of mutational hotspots. Knowledge of this distribution will allow us to streamline mutation screening through a targeted, stepwise approach when the ethnicity of a patient is known. This will facilitate the identification of individuals at risk, improving their care to prevent ophthalmological and vascular disease. Clin Trans Sci 2010; Volume 3: 295–298 相似文献
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Martin Stroedicke Yacine Bounab Nadine Strempel Konrad Klockmeier Sargon Yigit Ralf P. Friedrich Gautam Chaurasia Shuang Li Franziska Hesse Sean-Patrick Riechers Jenny Russ Cecilia Nicoletti Annett Boeddrich Thomas Wiglenda Christian Haenig Sigrid Schnoegl David Fournier Rona K. Graham Michael R. Hayden Stephan Sigrist Gillian P. Bates Josef Priller Miguel A. Andrade-Navarro Matthias E. Futschik Erich E. Wanker 《Genome research》2015,25(5):701-713
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Hagen?BombergEmail authorView authors OrcID profile Franziska?Meiser Sarah?Zimmer Martin?Bellgardt Thomas?Volk Daniel?I.?Sessler Heinrich?V.?Groesdonk Andreas?Meiser 《Journal of clinical monitoring and computing》2018,32(4):639-646
AnaConDa-100 ml (ACD-100, Sedana Medical, Uppsala, Sweden) is well established for inhalation sedation in the intensive care unit. But because of its large dead space, the system can retain carbon dioxide (CO2) and increase ventilatory demands. We therefore evaluated whether AnaConDa-50 ml (ACD-50), a device with half the internal volume, reduces CO2 retention and ventilatory demands during sedation of invasively ventilated, critically ill patients. Ten patients participated in this cross-over protocol. After sedation with isoflurane via ACD-100 for 24 h, the 5-h observation period started. During the first hour, ACD-100 was used; for the next 2 h, ACD-50; and for the last 2 h, ACD-100 was used again. Sedation was titrated to Richmond Agitation and Sedation Scale (RASS) score ??3 to ??4 and a processed electroencephalogram (Narcotrend Index, Narcotrend-Gruppe, Hannover, Germany) was recorded. Minute ventilation, CO2 elimination, and isoflurane consumption were compared. All patients were deeply sedated (Narcotrend Index, mean?±?SD: 38?±?10; RASS scores ??3 to ??5) and breathed spontaneously with pressure support throughout the observation period. Infusion rates of isoflurane and opioid, either remifentanil or sufentanil, as well as ventilator settings were unchanged. Minute ventilation and end-tidal CO2 were significantly reduced with the ACD-50, respiratory rate remained unchanged, and tidal volume decreased by 66?±?43 ml. End-tidal isoflurane concentrations were also slightly reduced while haemodynamic measures remained constant. The ACD-50 reduces the tidal volume needed to eliminate carbon dioxide without augmenting isoflurane consumption. 相似文献
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Franziska Albers Lydia Wachsmuth Timo Mauritz van Alst Cornelius Faber 《Molecular imaging and biology》2018,20(2):171-182
Recent developments of optogenetic tools and fluorescence-based calcium recording techniques enable the manipulation and monitoring of neural circuits on a cellular level. Non-invasive imaging of brain networks, however, requires the application of methods such as blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI), which is commonly used for functional neuroimaging. While BOLD fMRI provides brain-wide non-invasive reading of the hemodynamic response, it is only an indirect measure of neural activity. Direct observation of neural responses requires electrophysiological or optical methods. The latter can be combined with optogenetic control of neuronal circuits and are MRI compatible. Yet, simultaneous optical recordings are still limited to fiber-optic-based approaches. Here, we review the integration of optical recordings and optogenetic manipulation into fMRI experiments. As a practical example, we describe how BOLD fMRI in a 9.4-T small animal MR scanner can be combined with in vivo fiber-optic calcium recordings and optogenetic control in a multimodal setup. We present simultaneous BOLD fMRI and calcium recordings under optogenetic control in rat. We outline details about MR coil configuration, choice, and usage of opsins and chemically and genetically encoded calcium sensors, fiber implantation, appropriate light power for stimulation, and calcium signal detection, to provide a glimpse into challenges and opportunities of this multimodal molecular neuroimaging approach. 相似文献
28.
Steffen Moritz Jakob Fink Franziska Miegel Katharina Nitsche Vivien Kraft Peter Tonn Lena Jelinek 《Cognitive therapy and research》2018,42(5):650-660
The present study aimed to elucidate the profile of coping in patients with obsessive–compulsive disorder (OCD) in order to discern whether the disorder is characterized by an excess of maladaptive coping skills and/or a lack of adaptive coping skills. Sixty individuals with OCD were compared with 110 individuals with depression and 1050 nonclinical controls on the Maladaptive and Adaptive Coping Styles Questionnaire (MAX). Psychopathology was assessed with the Obsessive–Compulsive Inventory-Revised (OCI-R), the Yale-Brown Obsessive–Compulsive Scale (Y-BOCS), and the Patient Health Questionnaire-9 for depression (PHQ-9). Individuals with OCD and depression displayed more maladaptive coping and avoidance as well as less adaptive coping than nonclinical controls. Importantly, adaptive coping was significantly lower in individuals with OCD than in those with depression at a medium effect size, whereas the clinical groups were indistinguishable on maladaptive coping and avoidance. Lack of adaptive coping was strongly correlated with resistance to symptoms and poor insight in OCD (Y-BOCS), even after controlling for depression. Lack of adaptive coping skills may represent a specific pathogenetic factor in OCD. Longitudinal studies need to clarify whether strengthening adaptive skills during childhood and adolescence may help to prevent the progression from subclinical to manifest OCD. 相似文献
29.
Antidepressant and antipsychotic drugs are regularly encountered in different aspects of forensic toxicology, and some cases require the examination of hair samples. In this study, common antidepressant and antipsychotic drugs regarding hair concentrations over the past decades were reviewed. Although numerous publications around method validations, case reports, or controlled dose studies were found, apparently there is a lack of comprehensive data for many substances. Information on the hair length and dosage across the publications varied largely, and case numbers were generally low except for several retrospective controlled dose studies. Many substances were described only in method validations or case reports, and data were obtained from small case numbers. On the contrary, clozapine, haloperidol, amitriptyline, nortriptyline, risperidone and its metabolite, methylphenidate, citalopram, chlorpromazine, chlorprothixene, and quetiapine had a well‐founded database as these substances were investigated in controlled dose studies with higher case numbers. Given the advancements made in analytical techniques over the past years, gas chromatography–mass spectrometry and liquid chromatography with tandem mass spectrometry techniques were the methods of choice and allowed the detection of chemical compounds at low concentrations. The controversy around a potential use of hair analysis to estimate the dosage remains as dose‐concentration studies provided divergent results. A harmonization on the investigated hair length as well as on the extraction protocol would be of favor to achieve better comparability. Although hair analysis research focused mainly on drug abuse, availability of more data on antidepressants and antipsychotics would help to gain better knowledge and assist other forensic investigators. 相似文献
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Franziska Gaunitz Tobias Kieliba Mario Thevis Katja Mercer‐Chalmers‐Bender 《Drug testing and analysis》2020,12(1):27-40
This article comprises the development and validation of a protocol for the qualitative analysis of 61 phase I synthetic cannabinoid metabolites in urine originating from 29 synthetic cannabinoids, combining solid‐phase extraction (SPE) utilizing a reversed phase silica‐based sorbent (phenyl) with liquid chromatography–tandem mass spectrometry (LC?MS/MS). Validation was performed according to the guidelines of the German Society of Toxicological and Forensic Chemistry. Sufficient chromatographic separation was achieved within a total runtime of 12.3 minutes. Validation included specificity and selectivity, limit of detection (LOD), recovery and matrix effects, as well as auto‐sampler stability of processed urine samples. LOD ranged between 0.025 ng/mL and 0.5 ng/mL in urine. Recovery ranged between 43% and 97%, with only two analytes exhibiting recoveries below 50%. However, for those two analytes, the LODs were 0.05 ng/mL in urine. In addition, matrix effects between 81% and 185% were determined, whereby matrix effects over 125% were observed for 10 non‐first‐generation synthetic cannabinoid metabolites. The developed method enables the rapid and sensitive detection of synthetic cannabinoid metabolites in urine, complementing the spectrum of existing analytical tools in forensic case work. Finally, application to 61 urine samples from both routine and autopsy case work yielded one urine sample that tested positive for ADB‐PINACA N‐pentanoic acid. 相似文献