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The COVID-19 pandemic is unprecedented regarding its effects on human health, society, and economy To confine this pandemic, most governments in the world introduced strict measures such as border shutdowns, school closures, and social distancing Increasing the test capacities for SARS-CoV-2 detection is one key to ease restrictions;preventive and routine testing enables rapid infection cluster identification and prevents further spreading of the virus Amplifying the viral genetic information by PCR allows virus detection in a patient, while antibody testing gives information about bygone infections However, it is subject of current research if a positive antibody result guarantees a long-term immunity , Wiley-VCH Verlag All rights reserved

The increasing resolution of three-dimensional (3D) printing offers simplified access to, and development of, microfluidic devices with complex 3D structures. Therefore, this technology is increasingly used for rapid prototyping in laboratories and industry. Microfluidic free flow electrophoresis (μFFE) is a versatile tool to separate and concentrate different samples (such as DNA, proteins, and cells) to different outlets in a time range measured in mere tens of seconds and offers great potential for use in downstream processing, for example. However, the production of μFFE devices is usually rather elaborate. Many designs are based on chemical pretreatment or manual alignment for the setup. Especially for the separation chamber of a μFFE device, this is a crucial step which should be automatized. We have developed a smart 3D design of a μFFE to pave the way for a simpler production. This study presents (1) a robust and reproducible way to build up critical parts of a μFFE device based on high-resolution MultiJet 3D printing; (2) a simplified insertion of commercial polycarbonate membranes to segregate separation and electrode chambers; and (3) integrated, 3D-printed wells that enable a defined sample fractionation (chip-to-world interface). In proof of concept experiments both a mixture of fluorescence dyes and a mixture of amino acids were successfully separated in our 3D-printed μFFE device.

Impedimetric aptamer-based biosensors show high potential for handheld devices and point-of-care tests. In this review, we report on recent advances in aptamer-based impedimetric biosensors for applications in biotechnology. We detail on analytes relevant in medical and environmental biotechnology as well as food control, for which aptamer-based impedimetric biosensors were developed. The reviewed biosensors are examined for their performance, including sensitivity, selectivity, response time, and real sample validation. Additionally, the benefits and challenges of impedimetric aptasensors are summarized.

Aptamers are a specific class of ligands with high affinities comparable to antibodies, which are selected and synthesized in vitro. In combination with impedance spectroscopy as sensitive measurement method, we gain a class of biosensors with high potential for handheld devices and point-of-care tests. In this review, we report on recent advances in aptamer-based impedimetric biosensors. Besides giving a short summary of electrochemical measurement techniques, the most exciting innovative developments of detection strategies in the last decades are reviewed. Finally, important criteria for the comparison of aptamer-based biosensors are discussed.

Impedimetric aptamer-based biosensors show high potential for handheld devices and point-of-care tests. In this review, we report on recent advances in aptamer-based impedimetric biosensors for applications in biotechnology. We detail on analytes relevant in medical and environmental biotechnology as well as food control, for which aptamer-based impedimetric biosensors were developed. The reviewed biosensors are examined for their performance, including sensitivity, selectivity, response time, and real sample validation. Additionally, the benefits and challenges of impedimetric aptasensors are summarized.

Although recent trials provided level I evidence for the most common degenerative lumbar spinal disorders, treatment still varies widely. Thus, the Indications in Spinal Surgery (INDIANA) survey explores whether decision-making is influenced by specialty or personal emotional involvement of the treating specialist. Nationwide, neurosurgeons and orthopedic surgeons specialized in spine surgery were asked to answer an Internet-based questionnaire with typical clinical patient cases of lumbar disc herniation (DH), lumbar spinal stenosis (SS), and lumbar degenerative spondylolisthesis (SL). The surgeons were assigned to counsel a patient or a close relative, thus creating emotional involvement. This was achieved by randomly allocating the surgeons to a patient group (PG) and relative group (RG). We then compared neurosurgeons to orthopedic surgeons and the PG to the RG regarding treatment decision-making. One hundred twenty-two spine surgeons completed the questionnaire (response rate 78.7%). Regarding DH and SS, more conservative treatment among orthopedic surgeons was shown (DH: odds ratio [OR] 4.1, 95% confidence interval [CI] 1.7–9.7, p = 0.001; SS: OR 3.9, CI 1.8–8.2, p

A prospective randomized study.To compare occupational radiation exposure to the surgeon, as well as the patient, during posterior lumbar spine instrumentation in 10 navigated cases (navigated) versus 11 cases using the freehand technique (non-navigated).The use of navigation increases the accuracy of posterior lumbar instrumentation.A further speculated benefit of navigation is the reduction of radiation exposure of the surgeon. However, this has so far not been evaluated in such comparative manner.Radiation exposure to the surgeon was measured by digital dosimeters placed at the level of the eye, chest, and dominant forearm. Radiation exposure was measured from the time of positioning of the patient to the end of the procedure both for navigated (intraoperative 3-dimensional [3D] fluoroscopy-based) and non-navigated (2-dimensional fluoroscopy-guided) freehand posterior lumbar spine instrumentations. A 3D fluoroscopic scan was routinely performed at the end of the procedure for all patients.Patients were distributed evenly in the 2 groups in terms of sex, age, body mass index, and the number of operated levels. The accumulated radiation dose for the surgeon was significantly higher in the non-navigated group; up to 9.96 times. The radiation dose for the patient was higher with the freehand technique, 1884.8 cGy·cm (non-navigated) versus 887 cGy·cm (navigated), without reaching a statistically significant level.Radiation exposure to the surgeon during pedicle screw placement with the freehand technique is up to 9.96 times greater than with the use of navigation. In the latter group, the only radiation exposure comes from the preoperative-level control and positioning of the 3D C-arm before 3D fluoroscopic acquisition. Furthermore, neuronavigation also reduces the cumulative dose for the patient.2.

Surgery of lumbar disc herniations is one of the most common neurosurgical procedures. New surgical approaches and techniques are constantly evolving. We present our long-term follow-up results comparing standard open microdiscectomy (SOMD) and minimal access microdiscectomy (MAMD) for single-level lumbar disc herniations. Patients were randomized in two groups receiving either MAMD or SOMD. Physical and mental health and pain relief were assessed (ODI, SF-36 questionnaire, VAS leg and back pain). In addition, all patients received MR imaging for morphological evaluation of postoperative peridural scar tissue formation. Of the 60 initial patients (SOMD: 30 pts, MAMD: 30 pts), 38 were available for long-term follow-up. Mean follow-up time was 33 months. Long-term follow-up revealed significant postoperative pain relief in both groups. Good to excellent results concerning physical and mental health and pain relief were achieved in both groups. Significantly less peridural scar tissue formation was observed in the MAMD patients, but without clinical impact. MAMD is a feasible alternative to the standard open approach. Both groups show significant and long-lasting pain relief and good to excellent results regarding health-related quality of life. Congruent to our short-term results, we observed slightly but not statistically significant better clinical results in the MAMD group when compared to the SOMD group.

Objective Total disc replacement (TDR) is typically indicated in young patients with a cervical soft disc herniation. There are few data on the activity level of patients after cervical TDR, in particular from young patients who are expected to have a high activity level with frequent exercising. The expectation is that returning to active sports after cervical TDR is not restricted. Methods Fifty patients were treated with a monosegmental cervical TDR at our department between May 2006 and March 2012. Clinical status and radiographic parameters were evaluated preoperatively and during follow-up. In addition, information was gathered regarding neck disability index, pain, a questionnaire concerning athletic aspects, and a modified Tegner activity score. The study design was a prospective case series. Results All patients were treated with the Prestige artificial cervical disc for a single-level soft disc herniation with radiculopathy. The average age was 40 years, and the mean follow-up period was 53 months (range, 26–96). The median neck disability index during follow-up was 5, and median visual analog scale for pain was 2. Two professional athletes, 20 semiprofessionals, 24 hobby athletes, and 5 patients with a very low activity level were treated. The median time to resumption of sporting activity was 4 weeks after surgery. All professionals and semiprofessionals recovered to their previous activity level. All of the 20 hobby athletes recovered to resume their sport participation. The modified Tegner preoperative score was 4 and the postoperative score was 3.5 ( P = 0.806). Conclusions We found that cervical TDR did not prohibit sporting activities. All patients recovered and were able to take part in their previous activities at an appropriate intensity level.

Single-center prospective randomized controlled study.To evaluate the accuracy of robot-assisted (RO) implantation of lumbar/sacral pedicle screws in comparison with the freehand (FH) conventional technique.SpineAssist is a miniature robot for the implantation of thoracic, lumbar, and sacral pedicle screws. The system, studied in cadaver and cohort studies, revealed a high accuracy, so far. A direct comparison of the robot assistance with the FH technique is missing.Patients requiring mono- or bisegmental lumbar or lumbosacral stabilization were randomized in a 1:1 ratio to FH or RO pedicle screw implantation. Instrumentation was performed using fluoroscopic guidance (FH) or robot assistance. The primary end point screw position was assessed by a postoperative computed tomography, and screw position was classified (A: no cortical violation; B: cortical breach2 mm; C: ≥2 mm to4 mm; D: ≥4 mm to6 mm; E: ≥6 mm). Secondary end points as radiation exposure, duration of surgery/planning, and hospital stay were assessed.A total of 298 pedicle screws were implanted in 60 patients (FH, 152; RO, 146). Ninety-three percent had good positions (A or B) in FH, and 85% in RO. Preparation time in the operating room (OR), overall OR time, and intraoperative radiation time were not different for both groups. Surgical time for screw placement was significantly shorter for FH (84 minutes) than for RO (95 minutes). Ten RO screws required an intraoperative conversion to the FH. One FH screw needed a secondary revision.In this study, the accuracy of the conventional FH technique was superior to the RO technique. Most malpositioned screws of the RO group showed a lateral deviation. Attachment of the robot to the spine seems a vulnerable aspect potentially leading to screw malposition as well as slipping of the implantation cannula at the screw entrance point.

BackgroundThere is a lack of detailed information concerning patients’ sports and recreational activities after unicompartmental knee arthroplasty.HypothesisPatients treated by unicompartmental knee arthroplasty will be able to return to sports and activity.Study DesignCase series; Level of evidence, 4.MethodsThe authors surveyed 83 patients by postal questionnaires to determine their sporting and recreational activities at a mean follow-up of 18 ± 4.6 months (range, 12-28) after unicompartmental knee arthroplasty. For data analysis, patients were divided into groups of women and men, and older and younger patients (those above and below the median age of the group). The authors also assessed the state of general health (SF-36) of the patients at the time of the survey and compared the results with those of a matched (for age and side-diagnoses) reference population.ResultsBefore surgery, 77 of 83 patients were engaged in an average of 5.0 sports and recreational disciplines; postoperatively, 73 (88%) participated in an average of 3.1 different sports disciplines, resulting in a return to activity rate of 95%. The frequency of activities (sessions per week) was 2.9 preoperatively and remained constant at the time of survey (2.8). The group of older patients (mean age 73.0 y) revealed a significantly higher frequency than the group of younger patients (mean age 57.8 y). The minimum session length decreased from 66 minutes before surgery to 55 minutes after surgery. The most common activities after surgery were hiking, cycling, and swimming. Several high-impact activities, as well as the winter disciplines of downhill- and cross-country skiing had a significant decrease in participating patients. The majority of the patients (90.3%) stated that surgery had maintained or improved their ability to participate in sports or recreational activities. The patients generally scored very high on the SF-36 compared with the matched reference population. Higher SF-36 values in the physical-related domains correlated with an increased level of activity (r = 0.425). The preoperative body mass index showed a weak, negative correlation with the postoperative extent of activities (r = —0.282).ConclusionThe majority of patients returned to sports and recreational activity after unicompartmental knee arthroplasty. However, the numbers of different disciplines patients were engaged in decreased as well as the extent of activities. The activities in which most patients participated were primarily low- or midimpact. The patients scored higher on the SF-36 than age-related norms, which might be due to the patient-selection process for unicompartmental knee arthroplasty and geographical differences.

Purpose There is a lack of studies highlighting the outcome by different scores or parameters after surgery for recurrent disc herniations of the lumbar spine at the initial herniation site. This study assessed the quality of life after surgical treatment of recurrent herniations with different standardized validated outcome instruments. Methods During a 24-month period, 64 patients underwent (microscope assisted) surgery for recurrent disc herniations of the lumbar spine. The postoperative quality of life was tested with Short Form-36, the Oswestry Disability Index, the EuroQol health status 5D, and Prolo questionnaires. Leg and back pain before and after surgery was assessed. Results The patients showed a good overall outcome, but still not satisfying enough compared with the very good surgical results reported in the literature, for the surgical treatment of primary disc herniations. Conclusions Patients have to be informed carefully before surgery of recurrent lumbar disc herniations because of the less-promising outcome than after first time surgery for a lumbar disc herniation.

DNA-Microarrays have become a potent technology for high-throughput analysis of genetic regulation. However, the wide dynamic range of signal intensities of fluorophore-based microarrays exceeds the dynamic range of a single array scan by far, thus limiting the key benefit of microarray technology: parallelization. The implementation of multi-scan techniques represents a promising approach to overcome these limitations. These techniques are, in turn, limited by the fluorophores’ susceptibility to photobleaching when exposed to the scanner’s laser light. In this paper the photobleaching characteristics of cyanine-3 and cyanine-5 as part of solid state DNA microarrays are studied. The effects of initial fluorophore intensity as well as laser scanner dependent variables such as the photomultiplier tube’s voltage on bleaching and imaging are investigated. The resulting data is used to develop a model capable of simulating the expected degree of signal intensity reduction caused by photobleaching for each fluorophore individually, allowing for the removal of photobleaching-induced, systematic bias in multi-scan procedures. Single-scan applications also benefit as they rely on pre-scans to determine the optimal scanner settings. These findings constitute a step towards standardization of microarray experiments and analysis and may help to increase the lab-to-lab comparability of microarray experiment results.

Aneurysmal subarachnoid hemorrhage (SAH) has been reported to induce an intrathecal inflammatory reaction reflected by cytokine release, particularly interleukin-6 (IL-6), which correlates with early brain damage and poor outcome. The present study examines intrathecal IL-6 production together with clinical parameters, as a predictor of posthemorrhagic shunt dependency.Among 186 SAH patients admitted between July 2010 and December 2012, 82 received external ventricular drainage due to acute hydrocephalus. In these patients, cerebrospinal fluid (CSF) concentrations of IL-6 were measured within the first 14 days after SAH. Patients whose IL-6 values were not determined regularly and those who did not survive until discharge were excluded. The peak value of IL-6, ventricular infection during the hospital stay, microbial CSF culture, patient's age and sex, Hunt and Hess grade, and aneurysm location were assumed as predictive for shunt dependency.Sixty-nine patients were included, 24 of whom underwent shunt surgery. Peak IL-6 values of ≥10,000 pg/ml were significantly associated with a higher incidence of shunt dependency (p = 0.009). Additional risk factors were aneurysm location on the anterior cerebral artery and its branches or in the posterior circulation (p = 0.025), and age ≥60 years (p = 0.014). In a multivariate analysis, IL-6 ≥10,000 pg/ml appeared to be the only independent predictor for shunt dependency (p = 0.029) CONCLUSION: CSF IL-6 values of ≥10,000 pg/ml in the early post-SAH period may be a useful diagnostic tool for predicting shunt dependency in patients with acute posthemorrhagic hydrocephalus. The development of shunt-dependent posthemorrhagic hydrocephalus remains a multifactorial process.

Introduction: For the treatment of a soft disc herniation in the cervical spine the arthroplasty is often indicated in young patients. Especially this group of young patients has a high activity level with frequent exercising. However, the literature shows no data about the chances for a return to sports[for full text, please go to the a.m. URL], 129. Kongress der Deutschen Gesellschaft für Chirurgie