Selective Modification for Red-Shifted Excitability: A Small Change in Structure, a Huge Change in Photochemistry.

We developed three bathochromic, green-light activatable, photolabile protecting groups based on a nitrodibenzofuran (NDBF) core with D-π-A push-pull structures. Variation of donor substituents (D) at the favored ring position enabled us to observe their impact on the photolysis quantum yields. Comparing our new azetidinyl-NDBF (Az-NDBF) photolabile protecting group with our earlier published DMA-NDBF, we obtained insight into its excitation-specific photochemistry. While the "two-photon-only" cage DMA-NDBF was inert against one-photon excitation (1PE) in the visible spectral range, we were able to efficiently release glutamic acid from azetidinyl-NDBF with irradiation at 420 and 530 nm. Thus, a minimal change (a cyclization adding only one carbon atom) resulted in a drastically changed photochemical behavior, which enables photolysis in the green part of the spectrum.

The Effect of Collaborative Reviews of Electronic Patient-Reported Outcomes on the Congruence of Patient- and Clinician-Reported Toxicity in Cancer Patients Receiving Systemic Therapy: Prospective, Multicenter, Observational Clinical Trial.

BACKGROUND: Electronic patient-reported outcomes (ePRO) are a relatively novel form of data and have the potential to improve clinical practice for cancer patients. In this prospective, multicenter, observational clinical trial, efforts were made to demonstrate the reliability of patient-reported symptoms. OBJECTIVE: The primary objective of this study was to assess the level of agreement κ between symptom ratings by physicians and patients via a shared review process in order to determine the future reliability and utility of self-reported electronic symptom monitoring. METHODS: Patients receiving systemic therapy in a (neo-)adjuvant or noncurative intention setting captured ePRO for 52 symptoms over an observational period of 90 days. At 3-week intervals, randomly selected symptoms were reviewed between the patient and physician for congruency on severity of the grading of adverse events according to the Common Terminology Criteria of Adverse Events (CTCAE). The patient-physician agreement for the symptom review was assessed via Cohen kappa (κ), through which the interrater reliability was calculated. Chi-square tests were used to determine whether the patient-reported outcome was different among symptoms, types of cancer, demographics, and physicians' experience. RESULTS: Among the 181 patients (158 women and 23 men; median age 54.4 years), there was a fair scoring agreement (κ=0.24; 95% CI 0.16-0.33) for symptoms that were entered 2 to 4 weeks before the intended review (first rating) and a moderate agreement (κ=0.41; 95% CI 0.34-0.48) for symptoms that were entered within 1 week of the intended review (second rating). However, the level of agreement increased from moderate (first rating, κ=0.43) to substantial (second rating, κ=0.68) for common symptoms of pain, fever, diarrhea, obstipation, nausea, vomiting, and stomatitis. Similar congruency levels of ratings were found for the most frequently entered symptoms (first rating: κ=0.42; second rating: κ=0.65). The symptom with the lowest agreement was hair loss (κ=-0.05). With regard to the latency of symptom entry into the review, hardly any difference was demonstrated between symptoms that were entered from days 1 to 3 and from days 4 to 7 before the intended review (κ=0.40 vs κ=0.39, respectively). In contrast, for symptoms that were entered 15 to 21 days before the intended review, no congruency was demonstrated (κ=-0.15). Congruency levels seemed to be unrelated to the type of cancer, demographics, and physicians' review experience. CONCLUSIONS: The shared monitoring and review of symptoms between patients and clinicians has the potential to improve the understanding of patient self-reporting. Our data indicate that the integration of ePRO into oncological clinical research and continuous clinical practice provides reliable information for self-empowerment and the timely intervention of symptoms. TRIAL REGISTRATION: ClinicalTrials.gov NCT03578731; https://clinicaltrials.gov/ct2/show/NCT03578731.

Light-Induced Uncaging for Time-Resolved Observations of Biochemical Reactions by MAS NMR Spectroscopy.

Light-induced activation of biomolecules by uncaging of photolabile protection groups has found many applications for triggering biochemical reactions with minimal perturbations directly within cells. Such an approach might also offer unique advantages for solid-state NMR experiments on membrane proteins for initiating reactions within or at the membrane directly within the closed MAS rotor. Herein, we demonstrate that the integral membrane protein E. coli diacylglycerol kinase (DgkA), which catalyzes the phosphorylation of diacylglycerol, can be controlled by light under MAS-NMR conditions. Uncaging of NPE-ATP or of lipid substrate NPE-DOG by in situ illumination triggers its enzymatic activity, which can be monitored by real-time 31 P-MAS NMR. This proof-of-concept illustrates that combining MAS-NMR with uncaging strategies and illumination methods offers new possibilities for controlling biochemical reactions at or within lipid bilayers.

Scene reassembly after multimodal digitization and pipeline evaluation using photorealistic rendering.

Transparent objects require acquisition modalities that are very different from the ones used for objects with more diffuse reflectance properties. Digitizing a scene where objects must be acquired with different modalities requires scene reassembly after reconstruction of the object surfaces. This reassembly of a scene that was picked apart for scanning seems unexplored. We contribute with a multimodal digitization pipeline for scenes that require this step of reassembly. Our pipeline includes measurement of bidirectional reflectance distribution functions and high dynamic range imaging of the lighting environment. This enables pixelwise comparison of photographs of the real scene with renderings of the digital version of the scene. Such quantitative evaluation is useful for verifying acquired material appearance and reconstructed surface geometry, which is an important aspect of digital content creation. It is also useful for identifying and improving issues in the different steps of the pipeline. In this work, we use it to improve reconstruction, apply analysis by synthesis to estimate optical properties, and to develop our method for scene reassembly.

Limitations of N-Terminal Pro-B-Type Natriuretic Peptide in the Diagnosis of Heart Disease among Cancer Patients Who Present with Cardiac or Pulmonary Symptoms.

OBJECTIVES: Recognizing heart disease is relevant to oncologists because cancer patients are at an increased risk of cardiac mortality due to shared risk factors and the adverse effects of cancer therapy. This study assessed the extent to which the measurement of N-terminal pro-B-type natriuretic peptide (NT-proBNP) aids in the diagnosis of heart disease in addition to a history of coronary artery disease and the presence of atrial fibrillation (composite test). The NT- proBNP cutoff value was 100 pg/ml. METHODS: A series of 583 consecutive cancer patients (68.4 ± 11.0 years) who were referred because of cardiac or pulmonary symptoms prospectively underwent a diagnostic work-up. Heart disease was diagnosed if at least one of the following conditions was present: (a) history of coronary artery disease, (b) atrial fibrillation, (c) impaired left ventricular systolic function, (d) significant valvular disease, (e) pulmonary hypertension, or (f) left ventricular hypertrophy. RESULTS: Except for (a), all 6 conditions were associated with NT-proBNP >100 pg/ml. The sensitivity/specificity values of the composite test were 0.92/0.50 for any heart disease. Several extracardiac covariates were associated with NT-proBNP >100 pg/ml, which contributed to the low test specificity. CONCLUSIONS: The low specificity of NT-proBNP limits its value for the diagnosis of heart disease in cancer patients.

Venous thromboembolism and persistent pulmonary hypertension in cancer patients: a cross-sectional study.

BACKGROUND: Cancer patients are at increased risk for venous thromboembolism (VTE). OBJECTIVE: This monocenter cross-sectional study prospectively assessed the association between a history of ≥1 VTE episode and the presence of pulmonary hypertension (PH) among cancer patients presenting with pulmonary or cardiac symptoms. METHODS: A consecutive series of 583 patients underwent a diagnostic work-up for heart and lung disease. PH was diagnosed if a patient's peak systolic pressure gradient across the tricuspid valve was ≥35 mmHg, as measured by echocardiography. Using multiple logistic regression analysis, the association between VTE and PH was assessed, following adjustments for age, the presence of severe airway obstruction, atrial fibrillation and left heart diseases. RESULTS: The prevalence values for PH (n = 90) and a history of VTE (n = 72) were 15.4 and 12.3 %, respectively. The median time interval between the first VTE episode and referral was 43 months. The odds of PH was higher in the subgroup with VTE (19/72; 26.4 %) than that without VTE (71/511; 13.9 %) in the unadjusted analysis [odds ratio (OR) 2.2, 95 % confidence interval (CI) 1.2, 4.0] and the adjusted model [OR 2.4, 95 % CI 1.2, 4.5]. The risk of PH did not depend on the time interval between VTE and referral. Older age and the presence of severe airway obstruction, atrial fibrillation, and left heart diseases were also associated with an increased odds of PH. CONCLUSION: In cancer patients presenting with cardiac or pulmonary symptoms, previous VTE is associated with an increased risk of persistent PH.

Acute function of secreted amyloid precursor protein fragment APPsα in synaptic plasticity.

The key role of APP in the pathogenesis of Alzheimer disease is well established. However, postnatal lethality of double knockout mice has so far precluded the analysis of the physiological functions of APP and the APLPs in the brain. Previously, APP family proteins have been implicated in synaptic adhesion, and analysis of the neuromuscular junction of constitutive APP/APLP2 mutant mice showed deficits in synaptic morphology and neuromuscular transmission. Here, we generated animals with a conditional APP/APLP2 double knockout (cDKO) in excitatory forebrain neurons using NexCre mice. Electrophysiological recordings of adult NexCre cDKOs indicated a strong synaptic phenotype with pronounced deficits in the induction and maintenance of hippocampal LTP and impairments in paired pulse facilitation, indicating a possible presynaptic deficit. These deficits were also reflected in impairments in nesting behavior and hippocampus-dependent learning and memory tasks, including deficits in Morris water maze and radial maze performance. Moreover, while no gross alterations of brain morphology were detectable in NexCre cDKO mice, quantitative analysis of adult hippocampal CA1 neurons revealed prominent reductions in total neurite length, dendritic branching, reduced spine density and reduced spine head volume. Strikingly, the impairment of LTP could be selectively rescued by acute application of exogenous recombinant APPsα, but not APPsß, indicating a crucial role for APPsα to support synaptic plasticity of mature hippocampal synapses on a rapid time scale. Collectively, our analysis reveals an essential role of APP family proteins in excitatory principal neurons for mediating normal dendritic architecture, spine density and morphology, synaptic plasticity and cognition.

Are bone targeted agents still useful in times of immunotherapy? The SAKK 80/19 BTA pilot study.

Background: Patients with bone metastases from solid tumors often have additional treatment with bone targeted agents (BTAs) to avoid symptomatic skeletal events (SSEs) such as clinically significant pathological fracture leading toradiation therapy or surgery to the bone, spinal cord compression, or hypercalcemia. The absolute value of BTA treatment in the era of immunotherapy (IO) is unknown. Methods: Patients with bone metastases treated with immunotherapy within the Alpine Tumor Immunology Registry were compared based on whether they received an additional BTA such as denosumab or zoledronic acid. The primary endpoint was time to first SSE. Continuous data were summarized as median and range, categorical data using frequency counts and percentages. Kaplan-Meier estimates were used to describe and visualize the effect of categorical variables. Results: One hundred and ninety-seven patients with bone metastases and treatment with immunotherapy such as nivolumab (48 %), pembrolizumab (40 %), atezolizumab (12 %), ipilimumab (9 %) and other immunotherapy (5 %) were included. The most frequent tumor types were lung cancer (50 %), malignant melanoma (11 %), renal cell cancer (10 %) and bladder cancer (9 %), respectively. One hundred and twenty-two patients (62 %) received a BTA treatment (91 % denosumab). The median treatment duration of a BTA was 178 days (min: 1 day, max: 2010 days). Out of the 197 patients, 47 (24 %) experienced at least one SSE, 100 (51 %) had bone pain. Ten of the 122 patients (8 %) receiving a BTA developed osteonecrosis of the jaw (ONJ). The percentage of patients without an SSE at fixed time points was higher if treated with a BTA (e.g., at 6 months, 92 % [95 % CI: 84 % - 96 %] versus 88 % [95 % CI: 77 % - 94 %]), but no significant difference in time to first SSE (HR 0.69; 95 % CI 0.34-1.39, log-rank p = 0.29) or time to first bone pain (HR: 0.85; 95 % CI: 0.51-1.43, p = 0.54) between these two groups could be detected. There were differences in OS between patients treated with a BTA and patients not treated with a BTA (HR: 1.46; 95 % CI: 1.01-2.10, p = 0.043). Conclusion: No significant difference in time to first SSE or bone pain was observed between patients who have received a BTA or not when treated with immunotherapy. Based on these retrospective results the indication of BTAs to reduce SSEs in cancer patients under treatment with immunotherapy needs further evaluation.

Cardiotoxicity and cancer therapy: treatment-related cardiac morbidity in patients presenting with symptoms suggestive of heart or lung disease.

OBJECTIVES: Cardiac injury is one of the complications of cancer treatment. This study aimed to investigate the relationships between the types of radiotherapy of the chest (RT), chemotherapy (CT), cancer surgery (CS) and endocrine therapy (ET), and the presence of heart disease, and their associations with the serum level of N-terminal pro-B-type natriuretic peptide (NT-proBNP). METHODS: A consecutive series of 374 patients with cancer who were referred because of symptoms suggestive of heart or lung disease prospectively underwent a diagnostic workup. RESULTS: The prevalence of heart disease was 36.9%. RT administered before 1995 (n = 19) was associated with both increased odds of heart disease [adjusted odds ratio 10.3, 95% confidence interval 3.1-34.0] and higher ln-transformed NT-proBNP values (p < 0.01) compared to the control group (no RT or RT for right-sided breast cancer from 1995 onwards; n = 311). Anthracycline-treated patients (n = 54) had higher adjusted values for ln(NT-proBNP) compared to the control group (no CT; n = 243; p < 0.01) but no increased odds of heart disease. CONCLUSIONS: While pre-1995 RT and anthracycline-containing CT were associated with cardiac effects, there was no evidence that RT using modern cardioprotective techniques, CT in the absence of anthracyclines, CS or ET had detrimental effects on the heart.

Everolimus in metastatic renal cell carcinoma after failure of initial vascular endothelial growth factor receptor-tyrosine kinase inhibitor (VEGFr-TKI) therapy: results of an interim analysis of a non-interventional study.

BACKGROUND: Everolimus is approved for treatment of anti-vascular endothelial growth factor (VEGF)-refractory patients with metastatic renal cell carcinoma (mRCC). Clinical trials rarely mirror treatment reality. Thus, a broader evaluation of everolimus is valuable for routine use. PATIENTS AND METHODS: A German multicenter non-interventional study documented mRCC patients starting everolimus after failure of initial VEGF-targeted therapy. Primary endpoint was effectiveness, defined as time to progression (TTP) according to investigator assessment (time from first dose to progression). RESULTS: Of 382 documented patients, 196 were included in this interim analysis. In the efficacy population (n = 165), median TTP was 7.0 months (95% confidence interval (CI) 5.1-9.0). Among patients with < or ≥ 6 months of previous VEGF-targeted therapy, median TTP was 6.6 months (95% CI 3.8-not estimable) and 7.4 months (95% CI 4.6-9.6), respectively. Most common adverse events were anemia (13%) and dyspnea (14%). Physicians assessed high tolerance and documented high adherence to everolimus therapy (approximately 97%). CONCLUSION: In routine clinical practice, everolimus is effective, as measured by median TTP (longer than median progression-free survival in RECORD-1 trial), and well tolerated. Our results support everolimus use in anti-VEGF-refractory patients with mRCC.

Real-world patient-reported outcomes of breast cancer or prostate cancer patients receiving antiresorptive therapy for bone metastases: Final results of the PROBone registry study.

Background: In breast cancer and prostate cancer patients, bone metastases (BM) present the main cause of morbidity and often cause debilitating pain, impaired functioning and subsequent deterioration of quality of life (QoL). The management of BM is still challenging. Maintenance or improvement in QoL is the main goal of treatment. Antiresorptive treatment, such as denosumab and bisphosphonates, can help to reduce the frequency of skeletal complications, to control bone pain and potentially to improve QoL. The optimal time point for initiation of antiresorptive therapy is still discussed controversially. In patients with BM, bone pain can be used as a surrogate measure of QoL. However, limited data exist on health-related QoL in patients with BM under antiresorptive treatment. The PROBone registry study evaluated complaints and limitations caused by BM of breast and prostate cancer patients using patient-reported outcomes (PROs) in real-world in Germany. Methods: Between 2014 and 2019, 500 patients with histological confirmation of advanced breast or prostate cancer, diagnosed with BM at start of their first antiresorptive therapy were prospectively enrolled in 65 outpatient-centers specialized in medical oncology across Germany. Changes of QoL were assessed monthly from baseline until a maximum of 12 months using the validated pain score Functional Assessment of Cancer Therapy Quality of Life Measurement in patients with bone pain (FACT-BP) supplemented by questions on general pain and on the impact of time spent for treatment of illness on patients' daily activities. Statistical analysis was performed descriptively by relative and absolute frequencies. Results: In total, 486 patients were eligible for final analysis, of these 310 were diagnosed with breast cancer and 176 with prostate cancer. Median age was 67 years for breast cancer and 76 years for prostate cancer patients. 79.7% of breast cancer and 59.7% of prostate patients started antiresorptive treatment within 3 months after diagnosis of BM. More than 75% of patients suffered from bone pain at study inclusion. In total 52% of breast cancer patients and 47.9% of prostate cancer patients reported to take pain medication during the observation period. In breast and prostate cancer patients an initial pain reduction after start of BTA was observed: General pain and bone pain levels as well as the median FACT-BP score showed a constant improvement over the first months and maintained stable at a constant level afterwards. Subgroup analysis showed that patients without pain at baseline reported distinctly better FACT-BP scores throughout the whole observation period than patients with pain at baseline. Looking at time-stress (M)-scores, younger breast cancer patients (<65 years) showed highest burden especially during the first months of treatment. Conclusions: Our results indicate overall good adherence to current guideline recommendation, with most breast and prostate cancer patients starting antiresorptive therapy within the first 3 months after diagnosis of BM. This point gains even more importance as our data support current recommendations by ESMO guidelines as well as by German evidence-based S3-guidelines for diagnosis and treatment of breast and prostate cancer to initiate bone-targeted agents (BTA) as soon as BM are diagnosed, to keep pain levels at the lowest level possible, to minimize the debilitating effects of metastatic bone pain and maintain a good QoL. Bone pain management by an early use of BTA following BM diagnosis might improve patient care.

Comparative transcriptome profiling of amyloid precursor protein family members in the adult cortex.

BACKGROUND: The ß-amyloid precursor protein (APP) and the related ß-amyloid precursor-like proteins (APLPs) undergo complex proteolytic processing giving rise to several fragments. Whereas it is well established that Aß accumulation is a central trigger for Alzheimer's disease, the physiological role of APP family members and their diverse proteolytic products is still largely unknown. The secreted APPsα ectodomain has been shown to be involved in neuroprotection and synaptic plasticity. The γ-secretase-generated APP intracellular domain (AICD) functions as a transcriptional regulator in heterologous reporter assays although its role for endogenous gene regulation has remained controversial. RESULTS: To gain further insight into the molecular changes associated with knockout phenotypes and to elucidate the physiological functions of APP family members including their proposed role as transcriptional regulators, we performed DNA microarray transcriptome profiling of prefrontal cortex of adult wild-type (WT), APP knockout (APP-/-), APLP2 knockout (APLP2-/-) and APPsα knockin mice (APPα/α) expressing solely the secreted APPsα ectodomain. Biological pathways affected by the lack of APP family members included neurogenesis, transcription, and kinase activity. Comparative analysis of transcriptome changes between mutant and wild-type mice, followed by qPCR validation, identified co-regulated gene sets. Interestingly, these included heat shock proteins and plasticity-related genes that were both down-regulated in knockout cortices. In contrast, we failed to detect significant differences in expression of previously proposed AICD target genes including Bace1, Kai1, Gsk3b, p53, Tip60, and Vglut2. Only Egfr was slightly up-regulated in APLP2-/- mice. Comparison of APP-/- and APPα/α with wild-type mice revealed a high proportion of co-regulated genes indicating an important role of the C-terminus for cellular signaling. Finally, comparison of APLP2-/- on different genetic backgrounds revealed that background-related transcriptome changes may dominate over changes due to the knockout of a single gene. CONCLUSION: Shared transcriptome profiles corroborated closely related physiological functions of APP family members in the adult central nervous system. As expression of proposed AICD target genes was not altered in adult cortex, this may indicate that these genes are not affected by lack of APP under resting conditions or only in a small subset of cells.

In-situ X-ray fluorescence to investigate iodide diffusion in opalinus clay: Demonstration of a novel experimental approach.

During the last two decades, the Mont Terri rock laboratory has hosted an extensive experimental research campaign focusing on improving our understanding of radionuclide transport within Opalinus Clay. The latest diffusion experiment, the Diffusion and Retention experiment B (DR-B) has been designed based on an entirely different concept compared to all predecessor experiments. With its novel experimental methodology, which uses in-situ X-ray fluorescence (XRF) to monitor the progress of an iodide plume within the Opalinus Clay, this experiment enables large-scale and long-term data acquisition and provides an alternative method for the validation of previously acquired radionuclide transport parameters. After briefly presenting conventional experimental methodologies used for field diffusion experiments and highlighting their limitations, this paper will focus on the pioneer experimental methodology developed for the DR-B experiment and give a preview of the results it has delivered thus far.

Geometry of turbulent dissipation and the Navier-Stokes regularity problem.

The question of whether a singularity can form in an initially regular flow, described by the 3D incompressible Navier-Stokes (NS) equations, is a fundamental problem in mathematical physics. The NS regularity problem is super-critical, i.e., there is a 'scaling gap' between what can be established by mathematical analysis and what is needed to rule out a singularity. A recently introduced mathematical framework-based on a suitably defined 'scale of sparseness' of the regions of intense vorticity-brought the first scaling reduction of the NS super-criticality since the 1960s. Here, we put this framework to the first numerical test using a spatially highly resolved computational simulation performed near a 'burst' of the vorticity magnitude. The results confirm that the scale is well suited to detect the onset of dissipation and provide numerical evidence that ongoing mathematical efforts may succeed in closing the scaling gap.

Generation of conditional null alleles for APP and APLP2.

Proteolytical cleavage of the beta-amyloid precursor protein (APP) generates beta-amyloid, which is deposited in the brains of patients suffering from Alzheimer's disease (AD). Despite the well-established key role of APP for AD pathogenesis, the physiological function of APP and its close homologues APLP1 and APLP2 remains poorly understood. Previously, we generated APP(-/-) mice that proved viable, whereas APP(-/-)APLP2(-/-) mice and triple knockouts died shortly after birth, likely due to deficits of neuromuscular synaptic transmission. Here, we generated conditional knockout alleles for both APP and APLP2 in which the promoter and exon1 were flanked by loxP sites. No differences in expression were detectable between wt and floxed alleles, whereas null alleles were obtained upon crossing with Cre-transgenic deleter mice. These mice will now allow for tissue and time-point controlled knockout of both genes.

Markov random field surface reconstruction.

A method for implicit surface reconstruction is proposed. The novelty in this paper is the adaptation of Markov Random Field regularization of a distance field. The Markov Random Field formulation allows us to integrate both knowledge about the type of surface we wish to reconstruct (the prior) and knowledge about data (the observation model) in an orthogonal fashion. Local models that account for both scene-specific knowledge and physical properties of the scanning device are described. Furthermore, how the optimal distance field can be computed is demonstrated using conjugate gradients, sparse Cholesky factorization, and a multiscale iterative optimization scheme. The method is demonstrated on a set of scanned human heads and, both in terms of accuracy and the ability to close holes, the proposed method is shown to have similar or superior performance when compared to current state-of-the-art algorithms.

Global response of diacylglycerol kinase towards substrate binding observed by 2D and 3D MAS NMR.

Escherichia coli diacylglycerol kinase (DGK) is an integral membrane protein, which catalyses the ATP-dependent phosphorylation of diacylglycerol (DAG) to phosphatic acid (PA). It is a unique trimeric enzyme, which does not share sequence homology with typical kinases. It exhibits a notable complexity in structure and function despite of its small size. Here, chemical shift assignment of wild-type DGK within lipid bilayers was carried out based on 3D MAS NMR, utilizing manual and automatic analysis protocols. Upon nucleotide binding, extensive chemical shift perturbations could be observed. These data provide evidence for a symmetric DGK trimer with all of its three active sites concurrently occupied. Additionally, we could detect that the nucleotide substrate induces a substantial conformational change, most likely directing DGK into its catalytic active form. Furthermore, functionally relevant interprotomer interactions are identified by DNP-enhanced MAS NMR in combination with site-directed mutagenesis and functional assays.

Sensitized Two-Photon Activation of Coumarin Photocages.

Here we report the design of a new coumarin-based photolabile protecting group with enhanced two-photon absorption. Two-photon excited fluorescence (TPEF), color-tuned ultrafast transient absorption spectroscopy and infrared (IR) measurements are employed to photochemically characterize the newly designed ATTO 390-DEACM-cargo triad. Increased two-photon cross-section values of the novel cage in comparison to the widely used protecting group DEACM ([7-(diethylamino)coumarin-4-yl]methyl) are extracted from TPEF experiments. Femtosecond pump-probe experiments reveal a fast intramolecular charge transfer, a finding that is confirmed by quantum chemical calculations. Uncaging of glutamate is monitored in IR measurements by photodecarboxylation of the carbamate linker between the photolabile protecting group and the glutamate, showing the full functionality of the novel two-photon activatable photocage.

Loss of Swiss cheese/neuropathy target esterase activity causes disruption of phosphatidylcholine homeostasis and neuronal and glial death in adult Drosophila.

The Drosophila Swiss cheese (sws) mutant is characterized by progressive degeneration of the adult nervous system, glial hyperwrapping, and neuronal apoptosis. The Swiss cheese protein (SWS) shares 39% sequence identity with human neuropathy target esterase (NTE), and a brain-specific deletion of SWS/NTE in mice causes a similar pattern of progressive neuronal degeneration. NTE reacts with organophosphate compounds that cause a paralyzing axonal degeneration in humans and has been shown to degrade endoplasmic reticulum-associated phosphatidylcholine (PtdCho) in cultured mammalian cells. However, its function within the nervous system has remained unknown. Here, we show that both the fly and mouse SWS proteins can rescue the defects that arise in sws mutant flies, whereas a point mutation in the proposed active site cannot restore SWS function. Overexpression of catalytically active SWS caused formation of abnormal intracellular membraneous structures and cell death. Cell-specific expression revealed that not only neurons but also glia depend autonomously on SWS. In wild-type flies, endogenous SWS was detected by immmunohistochemistry in the endoplasmic reticulum (the primary site of PtdCho processing) of neurons and in some glia. sws mutant flies lacked NTE-like esterase activity and had increased levels of PtdCho. Conversely, overexpression of SWS resulted in increased esterase activity and reduced PtdCho. We conclude that SWS is essential for membrane lipid homeostasis and cell survival in both neurons and glia of the adult Drosophila brain and that NTE may play an analogous role in vertebrates.