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Biosensors have emerged as a valuable tool with high specificity and sensitivity for fast and reliable detection of hazardous substances in drinking water. Numerous substances have been addressed using synthetic biology approaches. However, many proposed biosensors are based on living, genetically modified organisms and are therefore limited in shelf life, usability and biosafety. We addressed these issues by the construction of an extensible, cell-free biosensor. Storage is possible through freeze drying on paper. Following the addition of an aqueous sample, a highly efficient cell-free protein synthesis (CFPS) reaction is initiated. Specific allosteric transcription factors modulate the expression of 'superfolder' green fluorescent protein (sfGFP) depending on the presence of the substance of interest. The resulting fluorescence intensities are analyzed with a conventional smartphone accompanied by simple and cheap light filters. An ordinary differential equitation (ODE) model of the biosensors was developed, which enabled prediction and optimization of performance. With an optimized cell-free biosensor based on the Shigella flexneri MerR transcriptional activator, detection of 6 μg/L Hg(II) ions in water was achieved. Furthermore, a completely new biosensor for the detection of gamma-hydroxybutyrate (GHB), a substance used as date-rape drug, was established by employing the naturally occurring transcriptional repressor BlcR from Agrobacterium tumefaciens.

Neurosurgical therapy aims to minimize the secondary brain damage that occurs after severe head injury. This includes the evacuation of intracranial space-occupying bleeding, reduction of intracranial volumes, external ventricular drainage in hematocephalus, and conservative therapy to influence increased intracranial pressure (ICP) and a decreased oxygen partial pressure [p(ti)o2]. When conservative treatment fails, a decompressive craniectomy might be successful in lowering ICP. From September 1997 until September 2002, 559 patients with severe head injuries were operated on. Eighty patients (14%) were treated by means of a decompressive craniectomy. The prognosis after decompression depends on the clinical signs and symptoms on admission, the patient's age, and the existence of major extracranial injuries. The guidelines used at this institution for decompressive craniectomy after failure of conservative intervention and evacuation of space-occupying hematomas include patient age less than 50 years without multiple trauma, patient age less than 30 years in the presence of major extracranial injuries, severe brain swelling on a computed tomography scan, the exclusion of a primary brainstem lesion or injury, and intervention before irreversible brainstem damage. Secondarily, intervention is undertaken after monitoring ICP and p(ti)o2 for an interval up to 48 hours after the accident before irreversible brainstem damage or generalized brain damage has occurred. [ABSTRACT FROM AUTHOR]

Ventral spondylodesis by autologous bone grafting in cases of degenerative disease of the cervical spine bears the disadvantage of the complication of pain at the iliac crest. The question is if these problems can be avoided by implanting intervertebral disc spacers. Between September 1997 and December 2000, we operated on 145 patients suffering from degenerative diseases, including osteochondrosis and/or disc prolapse, of the cervical spine. Without any patient diagnosis selection, we implanted various randomly chosen disc spacer types, including 52 titanium disc spacers (Cespace) by Aesculap, 40 titanium spacers by Weber, 36 titanium spacers by Intromed, and 17 carbonium spacers by AcroMed, through anterior access and after microsurgical discectomy and removal of the dorsal osteophytes by a high-speed drill. We evaluated the handling, radiographic contrast, and costs of implantation as well as the clinical outcome after 3 months and 1 year, respectively. All four disc spacer models are suitable for the anterior spondylodesis of the cervical spine. The titanium spacer by Weber features good handling characteristics and a moderate purchase price. Cost efficiency and easy handling characterize the Intromed cage. The radiographic contrast of the carbonium spacer by AcroMed is insufficient for a controlled implantation in some cases, especially in the lower cervical spine. The handling is good, but the price is high. The AcroMed and Intromed spacers show a tendency to penetrate the base and/or cartilaginous plate of the adjacent vertebrae. Results lead us to favor the Aesculap Cespace, which impresses us by its handling and moderate price. The final assessment depends on the long-term clinical outcome for the cases studied. [ABSTRACT FROM AUTHOR]