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OBJECTIVE Ischemic events within the territory of the choroidal artery are an important cause of morbidity after temporal lobe epilepsy (TLE) surgery. The aim of the present study was to evaluate the rate of these ischemic events, their clinical presentation, and impact on patients’ health-related quality of life (HRQoL) after TLE surgery. METHODS Four hundred twenty-two consecutive patients undergoing temporal resections for drug-resistant TLE were retrospectively analyzed. All patients underwent presurgical multidisciplinary assessment using a standard protocol comprising clinical, neuroradiological, neuropsychological, and EEG data. Postoperative complications with corresponding imaging, neurological deficits, and disease-specific HRQoL questionnaires were evaluated. RESULTS The overall complication rate was 7.8% (n = 33). Fourteen patients (3.3%) suffered from ischemic events causing 6 permanent motor deficits, 3 with permanent aphasias, and 6 visual field defects that exceeded quadrantanopia. In 8 patients with anterior choroidal artery infarction, accounting for 57% of all ischemic events, infarction volume correlated positively with the occurrence of new permanent neurological deficits (8666 vs 1692 mm3, p = 0.032). Despite the occurrence of ischemic events, HRQoL improved in 71% of patients. However, infarction volume showed a negative correlation trend with HRQoL (Pearson’s r = −0.390, p = 0.094). There was a trend toward increased risk for ischemic events in patients who underwent selective amygdalohippocampectomy compared to patients who underwent anterior temporal lobectomy or temporal lesionectomy (RR 0.96, 95% CI 0.93–0.99, p = 0.08). CONCLUSIONS Choroidal artery infarctions are rare but relevant complications after TLE surgery, presenting with variable clinical courses ranging from devastating neurological deterioration to complete recovery. Despite the occurrence of postoperative infarction, most patients report improvement of HRQoL after TLE surgery. This study showed that the type of surgery appears to modulate the risk for these ischemic events.

Journal of neuro-oncology 155(1), 71-80 (2021). doi:10.1007/s11060-021-03844-1, Published by Springer Science + Business Media B.V, Dordrecht [u.a.]

Zusammenfassung Hintergrund Die Diagnosestellung einer Kindesmisshandlung kann mit Irrtümern in beide Richtungen verbunden sein; einerseits können Misshandlungen unentdeckt bleiben oder aber Misshandlungen fälschlicherweise als Ursache für Verletzungen angenommen werden. Derartige diagnostische Irrtümer können dazu führen, dass Kinder dem misshandelnden Umfeld weiterhin ausgesetzt werden oder aber Kinder zu Unrecht in Obhut genommen und von ihrer Familie getrennt werden. Methoden Kinderschutzfälle aus den letzten 10 Jahren wurden retrospektiv anhand der elektronischen Krankenakte auf falsch-positive Fälle untersucht. Ein positives Ethikvotum der LMU München zur Publikation liegt vor. Ergebnisse Die als falsch-positiv identifizierten Fälle hatten als Ursache für vermeintliche nichtakzidentelle Verletzungsmuster eine genetisch gesicherte Osteogenesis imperfecta Typ 6, einen Lichen sclerosus und eine Hämophilie B. In allen Fällen wurde das Jugendamt miteinbezogen, in allen Fällen kam es zu einer Belastung für Eltern und Kinder, in einem Fall kam es zu einer, im Nachhinein ungerechtfertigten, temporären Inobhutnahme. Diskussion Eine interdisziplinär und multiprofessionell besetzte Kinderschutzgruppe an der Kinderklinik kann notwendige Differenzialdiagnosen ins Gespräch bringen und die Koordination mit dem Jugendamt und der Polizei erleichtern. Die Inobhutnahme durch das Jugendamt ist einerseits eine wichtige Maßnahme, um Kinder und Jugendliche vor weiteren Gefährdungen zu schützen, andererseits sollten ungerechtfertigte Inobhutnahmen vermieden werden, weil die daraus resultierende Trennung von Eltern und Kind zu erheblichen Belastungen führen kann. Die Konsultation der Rechtsmedizin ist hilfreich, um die Diagnose entsprechend einzugrenzen oder aber um alternative, medizinische Diagnosen anzubieten.

Intraoperative computed tomography (iCT) navigated dorsal instrumentation has been successfully introduced as a new clinical standard. The proximity of vital anatomic structures makes cervical spine instrumentation an especially delicate task. Therefore, navigated approaches might prove to be beneficial. In this study, the accuracy of conventional instrumentation was compared with iCT navigated dorsal cervical spine instrumentation with focus on cervical pedicle screws (CPSs) versus lateral mass screws (LMSs) and pathologies.We analyzed a prospective consecutive series of patients undergoing cervical dorsal instrumentation with iCT and spinal navigation and retrospectively analyzed a cohort that received conventional cervical instrumentation with C-arm fluoroscopy (control group). Accuracy was assessed with a modified Gertzbein-Robbins classification. Underlying pathologies were taken into account regarding accuracy in different entities.Fifty-nine patients were treated using iCT (357 screws: 238 CPSs, 119 LMSs), and 98 patients underwent conventional instrumentation (632 screws: 69 CPSs, 563 LMSs). We achieved an initial accuracy of 93.28% (n = 220 screws) in the iCT group and 80.9% (n = 511 screws) in the control group (P0.001). Significant differences were found regarding the accuracy of CPS placement in cases of degenerative disorders (iCT vs. control; 94% vs. 63%; P0.001) and trauma (iCT vs. control; 88% vs. 72%; P0.05). iCT yielded favorable precision rates in regard to LMS placement (iCT vs. control; 94.2% vs. 82%; P0.05).Accuracy of iCT navigated instrumentation was significantly higher than conventional instrumentation. An overall tendency toward the use of CPSs with iCT navigation is evident, increasing the mechanical properties of the construct. iCT appears to be especially beneficial in elective surgery cases of degenerative spinal disorders.

Purpose Instrumentation in spinal revision surgery is considered challenging. Altered or missing anatomical landmarks hinder the surgeons' intraoperative orientation. In recent history, the importance of navigated approaches to spinal screw placement is constantly increasing. A growing number of medical centers have introduced intraoperative CT (iCT) navigation as a new clinical standard. In this study, we compare the accuracy of dorsal iCT-navigated instrumentation in revision surgery versus primary interventions. Methods Between September 2017 and January 2019, we prospectively analyzed a consecutive series of dorsal instrumentation using iCT. Patients with previous operative interventions in the relevant spinal segments were included in the revision group and compared with a previously assessed group of primary interventions (nonrevision group). Each screw was assessed individually by an independent observer, making use of a modified Gertzbein and Robbins classification. Results In this period, 39 patients were treated in the revision group with a total amount of 269 implanted screws. We achieved an overall accuracy of 95.91% compared with 95.12% in the nonrevision group (46 patients, 287 screws). We found no significant difference in accuracy between the two groups or any anatomical region of the spine. Conclusion In summary, iCT-navigated screw placement yields a good accuracy in spinal revision surgery, without significant difference to primary interventions.

According to the published papers and books since the turn of the century, Pareto optimization is the dominating assessment method for multi-objective nonlinear optimization problems treated by population-based optimizers like Evolutionary Algorithms. However, is it always the method of choice for real-world applications, where either more than four objectives have to be considered, or the same type of task is repeated again and again with only minor modifications, in an automated optimization or planning process? This paper presents a classification of application scenarios and compares the Pareto approach with an extended version of the weighted sum, called cascaded weighted sum, for the different scenarios. Its range of application within the field of multi-objective optimization is discussed as well as its strengths and weaknesses., 20 pages, 10 figures

Generell stellen Wirbelsaulenverletzungen bei Kindern im Alter unter 16 Jahren eine seltene Verletzungsentitat dar. Fur Deutschland liegen keine belastbaren Daten bezuglich der Epidemiologie von Verletzungen der Wirbelsaule im Kindesalter vor. Gerade bei padiatrischen Patienten, bei denen sowohl die Anamnese, die klinische Untersuchung, aber auch die Durchfuhrung der bildgebenden Diagnostik haufig erschwert sind, mussen samtliche Hinweise auf eine Verletzung der Wirbelsaule mitberucksichtigt werden. Das Ziel der vorliegenden Studie war die Bereitstellung epidemiologischer Daten von padiatrischen Patienten mit Wirbelsaulenverletzungen in Deutschland, um diese zukunftig in die Entscheidungsfindung bei der Diagnostik und Therapie dieser Patienten einfliesen lassen zu konnen. Im Rahmen einer nationalen Multizenterstudie wurden retrospektiv Patientendaten innerhalb eines Zeitraums von 7 Jahren aus 6 Wirbelsaulenzentren erhoben. Neben den demografischen Daten wurden der Unfallmechanismus, die betroffene Wirbelsaulenregion und auch die Begleitverletzungen erhoben. Zudem erfolgte die Erfassung der bildgebenden Diagnostik sowie der jeweiligen Therapie. Es konnten 367 Kinder (weiblich: mannlich = 1:1,2) mit insgesamt 610 Verletzungen an der Wirbelsaule in die Studie eingeschlossen werden. Das mittlere Alter betrug 12 (±3,5) Jahre. Die haufigsten Unfallmechanismen in allen Altersgruppen waren ein Sturz aus unter 3 m Hohe sowie Verkehrsunfalle. Die bildgebende Diagnostik musste nur in Ausnahmefallen in Narkose durchgefuhrt werden. Wahrend jungere Kinder (0 bis 9 Jahre) eher Verletzungen im Bereich der Halswirbelsaule erlitten, zeigten sich Verletzungen der thorakolumbalen Wirbelsaule eher bei Kindern >10 Jahren. Die Kinder wiesen haufige Begleitverletzungen an Kopf und Extremitaten auf. Im Bereich der Wirbelsaule befanden sich weitere Verletzungen meist benachbart und nur selten in anderen Regionen. Rund 75 % der Kinder wurden konservativ behandelt. Die Ergebnisse unterscheiden sich von den Erkenntnissen aus der Erwachsenenmedizin und beschreiben spezielle Gegebenheiten fur padiatrische Patienten mit Wirbelsaulenverletzungen. Trotz gewisser Limitationen konnen sie so bei der Entscheidungsfindung uber die durchzufuhrende Diagnostik und Therapie dieser Patienten helfen.

The aim of this study is to detect the presence of blood spinal cord barrier (BSCB) disruption in patients with degenerative cervical myelopathy (DCM). In this prospective non-randomized controlled cohort study, 28 patients with DCM were prospectively included. All patients had indication for neurosurgical decompression. Furthermore, 38 controls with thoracic abdominal aortic aneurysm (TAAA) and indication for surgery were included. All patients underwent neurological examination. Regarding BSCB disruption and intrathecal immunoglobulin (Ig) concentrations, cerebrospinal fluid (CSF) and blood serum were examined for albumin, IgG, IgA and IgM. Quotients (Q) (CSF/serum) were standardized and calculated according to Reibers’ diagnostic criteria. Patients and controls distinguished significantly in their clinical status. AlbuminQ, as expression of BSCB disruption, was significantly increased in the DCM patients compared to the controls. Quotients of IgG and IgA differed significantly between the groups as an expression of intrathecal diffusion. In the subgroup analysis of patients with mild/moderate clinical status of myelopathy and patients with severe clinical status, the disruption of the BSCB was significantly increased with clinical severity. Likewise, IgAQ and IgGQ presented increased quotients related to the clinical severity of myelopathy. In this study, we detected an increased permeability and disruption of the BSCB in DCM patients. The severity of BSCB disruption and the diffusion of Ig are related to the clinical status in our patient cohort. Having documented this particular pathomechanism in patients with DCM, we suggest that this diagnostic tool cloud be an important addition to surgical decision making in the future. These slides can be retrieved under Electronic Supplementary Material.

The urea-creatinine ratio (UCR) has been proposed as potential biomarker for critical illness-associated catabolism. Its role in the context of aneurysmal subarachnoid hemorrhage (aSAH) remains to be elucidated, which was the aim of the present study.We enrolled 66 patients with aSAH with normal renal function and 36 patients undergoing elective cardiac surgery as a control group for the effects of surgery. In patients with aSAH, the predictive or diagnostic value of early (day 0-2) and critical (day 5-7) UCRs was assessed with regard to delayed cerebral ischemia (DCI), DCI-related infarction, and clinical outcome after 12 months.Preoperatively, UCR was similar both groups. Within 2 days postoperatively, UCRs increased significantly in patients in the elective cardiac surgery group (P0.001) but decreased back to baseline on day 5-7 (P = 0.245), whereas UCRs in patients with aSAH increased to significantly greater levels on day 5-7 (P = 0.028). Greater early or critical UCRs were associated with poor clinical outcomes (P = 0.015) or DCI (P = 0.011), DCI-related infarction (P = 0.006), and poor clinical outcomes (P 0.001) respectively. In multivariate analysis, there was an independent association between greater early UCRs and poor clinical outcomes (P = 0.026).In this exploratory study of UCR in the context of aSAH, greater early values were predictive for a poor clinical outcome after 12 months, whereas greater critical values were associated with DCI, DCI-related infarctions, and poor clinical outcomes. The clinical implications as well as the pathophysiologic relevance of protein catabolism should be explored further in the context of aSAH.

Scientific reports 11(1), 2497 (2021). doi:10.1038/s41598-021-81766-8, Published by Macmillan Publishers Limited, part of Springer Nature, [London]

Objective Endovascular treatment of ruptured cerebral aneurysms frequently requires antiplatelet medication to prevent thromboembolism. This might raise concern regarding the risk of postprocedural hemorrhage (pH), e.g. from placement of intracranial probes. We explored the risk of PH associated with standard antiplatelet therapy (sAP: acetylsalicylic acid, and/or clopidogrel) in the context of aneurysmal subarachnoid hemorrhage (aSAH). Methods We retrospectively reviewed a total of 146 consecutive cases with cerebral aneurysms treated between 1/2011–12/2015, and distinguished between minor (0.5 cm3) - 4 cm3) or major (> 4 cm3) PH occurring within four weeks after intervention. A separate analysis included hemorrhages related to placement of intracranial probes and drainages in the subgroup of 99 cases with such surgical interventions (pPH). Clinical outcome was assessed via Glasgow Outcome Scale (GOS) twelve months after aSAH. Results A total of 49 cases (33.6%) in the overall sample sustained PH, there were 19 cases of pPH. Multifactorial analyses yielded sAP as an independent predictor for minor, but not major PH (p Conclusions sAP was associated with a higher rate of minor PH and, more specifically, of minor pPH. However, it was neither accompanied by the occurrence of major hemorrhages nor by unfavorable clinical outcome. Future prospective studies should confirm these observations and hemorrhage risks associated with extended anticoagulation regimes after complex interventions and intra-arterial vasospasm therapy should be explored in order to facilitate interdisciplinary decision-making in aSAH.

In contrast to traditional ways on how to teach engineering students, modern concepts include problem-based learning approaches, offering the possibility to include project courses in the curriculum. As a step beyond, large international competition formats arose in recent years, offering very complex tasks that are not feasible to be treated in one (or few) regular courses only. That is, because they are often organized by industry-related consortia, aiming for a different education perspective that increases employability. In a natural way, such projects value deeper understanding of theory modules, but emphasize on the transfer to practical solutions. Since the origin does not come from university staff, participation in such competitions is based on student efforts and organization, creating a unique level of demand and ownership that can only be inflamed by very high motivation. In order to sustain such large-scale projects from the faculty’s perspective, the combination of in- and off-curricular elements can help to lower the students’ workload to feasible levels. Seamlessly integrated, this enhances learning experiences and helps to keep project members highly motivated and productive. In this paper, we present the idea and impact of an additional graduation certificate as a means to stabilize such large-scale projects by providing a framework and enhancing motivation in the students. By way of doing so, the university can give formal credit for the informal learning and valuable knowledge acquired in off-curricular activities. We discuss which certificate elements were determined to be useful and how our findings were solidified by a detailed survey. Even though this work centers on a specific example, we will emphasize the general conclusions that can be drawn and which guidelines might be transferred to similar other projects.

In general, pediatric spinal injuries are rare. No reliable data on the epidemiology of spinal injuries in pediatric patients in Germany are available. Especially in pediatric patients, for whom the medical history, clinical examination and the performance of imaging diagnostics are difficult to obtain, all available information on a spinal injury must be taken into account.The aim of this study was to provide epidemiological data for pediatric patients with spinal trauma in Germany in order to enhance future decision-making for the diagnostics and treatment of these patients.Within the framework of a national multicenter study, data were retrospectively obtained from 6 German spine centers for 7 years between January 2010 and December 2016. In addition to the demographic data, the clinical databases were screened for specific trauma mechanisms, level of injury as well as accompanying injuries. Furthermore, diagnostic imaging and the treatment selected were also analyzed.A total of 367 children (female: male = 1:1.2) with a total of 610 spinal injuries were included in this study. The mean age was 12 years (±3.5 years). The most frequent trauma mechanisms were falls from3 m and traffic accidents. The imaging diagnostics were only rarely carried out with the child under anesthesia. Younger children (0-9 years old) suffered more injuries to the cervical spine, whereas injuries to the thoracic and lumbar spine were more frequently found in older children (10 years old). The children frequently showed accompanying injuries to the head and the extremities. Accompanying spinal injuries mostly occurred in adjacent regions and only rarely in other regions. Around 75% of the children were treated conservatively.The results were different from the knowledge obtained from adult patients with spinal trauma and describe the special circumstances for pediatric patients with spinal trauma. Despite certain limitations these facts may help to enhance future decision-making for the diagnostics and treatment of these patients.

Background Our objective was to investigate the effect of intraoperative dexamethasone administration on wound healing, complications, and clinical outcome in patients with posterior surgery for cervical spondylotic myelopathy (CSM). Methods We conducted a retrospective study of patients with CSM undergoing dorsal instrumentation and decompression of the cervical spine. The senior surgeon decided if administration of dexamethasone (40 mg intravenously) was indicated. Patients were divided into two groups: dexamethasone group (DG) and non-dexamethasone group (nDG). All patients were monitored for pre- and postoperative neurologic symptoms and complications. Clinical follow-up was evaluated with the Neck Disability Index (NDI) and the modified Japanese Orthopaedic Association (mJOA) score. Results A total of 49 patients were included (DG, 25; nDG, 24). DG and nDG patients showed no significant differences in pre- and postoperative findings. Five patients in the DG had wound healing complications compared with patients in the nDG (p = 0.021), and one died due to infection. Apart from that, we did not observe any significant differences between the two groups regarding complications, neurologic symptoms, and follow-up (NDI and mJOA). Conclusion Intraoperative dexamethasone administration had no influence on the postoperative outcome and follow-up. A significantly higher rate of wound infections was detected in the DG. These data support the hypothesis that intraoperative dexamethasone bolus application in CSM lacks benefit.

Background To evaluate whether decompression in lumbar spinal stenosis without fusion leads to sufficient improvement of back pain and leg pain and whether re-decompression alone is sufficient for recurrent lumbar spinal stenosis for patients without signs of instability. Material and Methods A successive series of 102 patients with lumbar spinal stenosis (with and without previous lumbar surgery) were treated with decompression alone during a 3-year period. Data on pre- and postoperative back pain and leg pain (numerical rating scale [NRS] scale) were retrospectively collected from questionnaires with a return rate of 65% (n = 66). The complete cohort as well as patients with first-time surgery and re-decompression were analyzed separately. Patients were dichotomized to short-term follow-up (< 100 weeks) and long-term follow-up (> 100 weeks) postsurgery. Results Overall, both back pain (NRS 4.59 postoperative versus 7.89 preoperative; p Conclusions Decompression of lumbar spinal stenosis without fusion led to a significant and similar reduction of back pain and leg pain in a short-term and a long-term follow-up group. Patients without previous surgery benefited significantly better, whereas patients with previous decompression benefited regarding back pain, especially for long-term follow-up with a clear trend in favor of leg pain.

Highlights • Degenerative cervical myelopathy is the most common cause of chronic impairment of the spinal cord. • MRI-based anatomical assessment of cerebral and cerebellar areas revealed significant tissue volume reduction in DCM patients compared to healthy controls. • Disease severity correlated with cerebral and cerebellar atrophy in the primary motor cortex, primary somatosensory cortex and cerebellar areas. • Chronic injury to the spinal cord seems to have impact on remote anatomical structures in the brain., This study investigated supra- and infratentorial structural gray and white matter (GM, WM) alterations in patients with degenerative cervical myelopathy (DCM) as an indicator of secondary harm due to chronic cervical cord compression and micro trauma. With MRI-based anatomical assessment and subsequent voxel-based morphometry analyses, pre- and postoperative volume alterations in the primary motor cortex (MI), the primary somatosensory cortex (SI), the supplementary motor area (SMA), and the cerebellum were analyzed in 43 DCM patients and 20 controls. We assessed disease-related symptom severity by the modified Japanese Orthopaedic Association scale (mJOA). The study also explored symptom severity-based brain volume alterations as well as their association with clinical status. Patients had lower mJOA scores (p = .000) and lower GM volume than controls in SI (p = .016) and cerebellar regions (p = .001). Symptom severity-based subgroup analyses revealed volume reductions in almost all investigated GM ROIs (MI: p = .001; CB: p = .040; SMA: p = .007) in patients with severe clinical symptoms as well as atrophy already present in patients with moderate symptom severity. Clinical symptoms in DCM were associated with cortical and cerebellar volume reduction. GM volume alterations may serve as an indicator of both disease severity and ongoing disease progression in DCM, and should be considered in further patient care and treatment monitoring.

Climate change and the increasing world population will lead to an increased water shortage. This gives rise to the need for plant cultivars which are drought tolerant. Solanum tuberosum L. is important not only as a nutritive rich food, but starch potatoes are of great value for the industry. Two starch genotypes of S. tuberosum L. divergently responding to osmotic stress were subjected to medium containing 0.2 M sorbitol in vitro. A targeted metabolomics approach was performed in which 42 metabolites were analysed 11 days after the transfer of the plants to the experimental medium. The sensitive genotype displayed stress responses comprising higher abundant metabolites such as phenylalanine, proline and sucrose and a decrease e.g. in GABA and fumaric acid. These can be used for protein build up, nitrogen storage and the protection through osmotic active compounds. In contrast, the tolerant genotype showed a higher abundance in compounds used as osmolytes (citric acid and proline), which might give rise to acclimatisation to the stress. Interestingly, in chromatograms of both genotypes a high sorbitol peak was detected, whereas control plants or plants treated with 4.8 % PEG 8000 did not accumulate this substance. Conclusively, sorbitol is taken up during in vitro growth, which raises the question for the fate and effect of the incorporated sorbitol.

States act through international organizations (IOs) in order to address global and international problems (Abbott and Snidal 1998). In Hylke Dijkstra’s new book, International Organizations and Mi...

Objective: Sarcoidosis is a multisystemic granulomatous disease of unknown cause which affects the lung or bilateral hilar lymphadenopathy in over 90% of the cases. Neurosarcoidosis (NS) is rare an...

Background Anterior cervical diskectomy and fusion (ACDF) or posterior foraminotomy (PF) are standard treatment options for cervical radiculopathy due to disk prolapse. Which method produces superior results has not yet been established. One reason for the dilemma, among others, is a lack of detailed outcome analysis in previous studies. We quantified outcome to compare both methods in our retrospective single-center series. Method We conducted a retrospective analysis of 107 patients with cervical radiculopathy who were operated on via ACDF or via PF. Demographic data, symptoms, neurologic status, and pathology were recorded and correlated to outcome parameters such as Odom's criteria, visual analog scale values of radicular pain, Neck Disability Index values, and subjective satisfaction, which were also compared between both treatment groups. Intraoperative data, early and late complications, and reoperations were recorded and compared between both surgical groups. Results None of the recorded preoperative data were predictive for postoperative outcome parameters. Patients in the PF group reported better overall outcome (Odom's criteria) and greater relief of radicular and neck pain. Operative time and blood loss were less in the PF group. Both groups showed comparable early complication rates, but PF patients tended to have more late reoperations. Conclusion Due to a better overall outcome as well as greater relief of radicular and neck pain in our cohort, we consider PF the first-line treatment if morphology of the pathology is suitable.

Glyoxylate is a peroxisomal intermediate of photorespiration, the recycling pathway for 2-phosphoglycolate (2-PG) produced by the oxygenase activity of Rubisco. Under hot and dry growth conditions, photorespiratory intermediates can accumulate and must be detoxified by alternative pathways, including plastidal reactions. Moreover, there is evidence that chloroplasts are capable of actively producing glyoxylate from glycolate. Further metabolic steps are unknown, but probably include a CO2 release step. Here, we report that CO2 production from glycolate and glyoxylate in isolated tobacco chloroplasts can be inhibited by pyruvate, but not related compounds. We isolated a protein fraction that was enriched for the chloroplast pyruvate dehydrogenase complex (PDC). The fraction contained a protein complex of several MDa in size that included all predicted subunits of the chloroplast PDC and a so far unidentified HSP93-V/ClpC1 heat shock protein. Glyoxylate competitively inhibited NADH formation from pyruvate in this fraction. The Km for pyruvate and the Ki for glyoxylate were 330 and 270 μM, respectively. Glyoxylate decarboxylation was also enriched in this fraction and could be in turn inhibited by pyruvate. Based on these data, we suggest that the chloroplast PDC might be part of a pathway for glycolate and/or glyoxylate oxidation in chloroplasts.

Here, a first GelMap of the chloroplast “protein complex proteome” of Arabidopsis thaliana is presented. The GelMap software tool allows assigning multiple proteins to gel spots, thereby taking advantage of the high sensitivity of state-of-the-art mass spectrometry systems. Furthermore, the software allows functional annotation of all identified proteins. If applied to a 2D blue native (BN)/SDS gel, GelMap can selectively display protein complexes of low abundance. For the chloroplast GelMap, highly purified organelles were separated by 2D BN/SDS PAGE and spots were automatically detected using Delta 2D software. Within 287 spots, a total of 1841 proteins were identified (on average 6.4 proteins per spot), representing a set of 436 non redundant proteins. Most of these proteins form part of protein complexes. The quality of the map is reflected by its inclusion of a more or less complete set of protein complexes described for chloroplasts in the literature. The GelMap is publically available at www.gelmap.de/arabidopsis-chloro and may be used as a resource for identifying novel protein complexes within any of its functional categories. Biological significance The chloroplast GelMap represents a data resource for the definition of protein complexes in the model plant A. thaliana . It should be useful for in depth understanding of chloroplast biochemistry, as illustrated by the discovery of so far unknown protein complexes. The GelMap is publically available at www.gelmap.de/arabidopsis-chloro .

Photorespiration has been suggested as a target for increasing photosynthesis for decades. Within the last few years, three bypass pathways or reactions have been designed and tested in plants. The three reactions bypass photorespiration either in the chloroplast or in the peroxisome, or oxidize glycolate completely to CO(2) in the chloroplast. The reactions differ in their demand for energy and reducing power as well as in the catabolic fate of glycolate. The design, energy balance, and reported benefits of the three bypasses are compared here, and an outlook on further optimization is given.