Analysis of cellularity in H&E-stained rat bone marrow tissue via deep learning.

Our objective was to develop an automated deep-learning-based method to evaluate cellularity in rat bone marrow hematoxylin and eosin whole slide images for preclinical safety assessment. We trained a shallow CNN for segmenting marrow, 2 Mask R-CNN models for segmenting megakaryocytes (MKCs), and small hematopoietic cells (SHCs), and a SegNet model for segmenting red blood cells. We incorporated the models into a pipeline that identifies and counts MKCs and SHCs in rat bone marrow. We compared cell segmentation and counts that our method generated to those that pathologists generated on 10 slides with a range of cell depletion levels from 10 studies. For SHCs, we compared cell counts that our method generated to counts generated by Cellpose and Stardist. The median Dice and object Dice scores for MKCs using our method vs pathologist consensus and the inter- and intra-pathologist variation were comparable, with overlapping first-third quartile ranges. For SHCs, the median scores were close, with first-third quartile ranges partially overlapping intra-pathologist variation. For SHCs, in comparison to Cellpose and Stardist, counts from our method were closer to pathologist counts, with a smaller 95% limits of agreement range. The performance of the bone marrow analysis pipeline supports its incorporation into routine use as an aid for hematotoxicity assessment by pathologists. The pipeline could help expedite hematotoxicity assessment in preclinical studies and consequently could expedite drug development. The method may enable meta-analysis of rat bone marrow characteristics from future and historical whole slide images and may generate new biological insights from cross-study comparisons.

Outcomes of acute versus delayed total hip arthroplasty following acetabular fracture.

PURPOSE: Post-traumatic arthritis is known complication following acetabular fracture. The aim was to compare mid- to long-term outcomes of acute THA (aTHA) for acetabular fracture and delayed THA (dTHA) following failure of ORIF or conservative management. METHODS: We retrospectively analysed 60 THA (21 aTHA; 39 dTHA) performed for acetabular fracture between 2004 and 2014 in 60 patients with a mean age of 59 years (20-94). Functional and Radiographic outcomes were assessed at a mean follow-up of 5 years (2-13) utilizing Oxford, Harris Hip (HHS), and Postel Merle d'Aubigné (PMA) scores and Brooker classification. RESULTS: The mean HHS (73), Oxford (32) and PMA (12) scores were significantly lower in the aTHA group. Acute THA was significantly associated with lower postoperative Oxford (ß = -4.2), HHS (ß = -7.8), and PMA (ß = -2.2) scores at mean 5 years (2-13). Eleven patients returned to the operating room. There were no significant differences between THA performed in acute or delayed fashion. The two primary reasons for revision were periprosthetic joint infection (n = 5) and aseptic loosening (n = 4). Survivorship free from reoperation at 10 years was 91% and 82% for aTHA and dTHA, respectively (p = 0.24). Increased PMA scores were associated with decreased overall survival of the THA free from reoperation (HR = 0.60). The degree of heterotopic ossification was significantly higher in the aTHA group (p < 0.001). CONCLUSION: Acute THA in the setting of acetabular fracture is a technically challenging procedure. However, in the present series, aTHA provided satisfactory immediate stability and good survivorship at 10 years in a medically vulnerable patient population. LEVEL OF EVIDENCE: Level 3; Therapeutic study.

Quantitative systems pharmacology model of the amyloid pathway in Alzheimer's disease: Insights into the therapeutic mechanisms of clinical candidates.

Despite considerable investment into potential therapeutic approaches for Alzheimer's disease (AD), currently approved treatment options are limited. Predictive modeling using quantitative systems pharmacology (QSP) can be used to guide the design of clinical trials in AD. This study developed a QSP model representing amyloid beta (Aß) pathophysiology in AD. The model included mechanisms of Aß monomer production and aggregation to form insoluble fibrils and plaques; the transport of soluble species between the compartments of brain, cerebrospinal fluid (CSF), and plasma; and the pharmacokinetics, transport, and binding of monoclonal antibodies to targets in the three compartments. Ordinary differential equations were used to describe these processes quantitatively. The model components were calibrated to data from the literature and internal studies, including quantitative data supporting the underlying AD biology and clinical data from clinical trials for anti-Aß monoclonal antibodies (mAbs) aducanumab, crenezumab, gantenerumab, and solanezumab. The model was developed for an apolipoprotein E (APOE) ɛ4 allele carrier and tested for an APOE ɛ4 noncarrier. Results indicate that the model is consistent with data on clinical Aß accumulation in untreated individuals and those treated with monoclonal antibodies, capturing increases in Aß load accurately. This model may be used to investigate additional AD mechanisms and their impact on biomarkers, as well as predict Aß load at different dose levels for mAbs with known targets and binding affinities. This model may facilitate the design of scientifically enriched and efficient clinical trials by enabling a priori prediction of biomarker dynamics in the brain and CSF.

Assessment of Color Reproducibility and Mitigation of Color Variation in Whole Slide Image Scanners for Toxicologic Pathology.

Digital pathology workflows in toxicologic pathology rely on whole slide images (WSIs) from histopathology slides. Inconsistent color reproduction by WSI scanners of different models and from different manufacturers can result in different color representations and inter-scanner color variation in the WSIs. Although pathologists can accommodate a range of color variation during their evaluation of WSIs, color variability can degrade the performance of computational applications in digital pathology. In particular, color variability can compromise the generalization of artificial intelligence applications to large volumes of data from diverse sources. To address these challenges, we developed a process that includes two modules: (1) assessing the color reproducibility of our scanners and the color variation among them and (2) applying color correction to WSIs to minimize the color deviation and variation. Our process ensures consistent color reproduction across WSI scanners and enhances color homogeneity in WSIs, and its flexibility enables easy integration as a post-processing step following scanning by WSI scanners of different models and from different manufacturers.

Toxicologic Pathology Forum: A Roadmap for Building State-of-the-Art Digital Image Data Resources for Toxicologic Pathology in the Pharmaceutical Industry.

Digitization of histologic slides brings with it the promise of enhanced toxicologic pathology practice through the increased application of computational methods. However, the development of these advanced methods requires access to substrate image data, that is, whole slide images (WSIs). Deep learning methods, in particular, rely on extensive training data to develop robust algorithms. As a result, pharmaceutical companies interested in leveraging computational methods in their digital pathology workflows must first invest in data infrastructure to enable data access for both data scientists and pathologists. The process of building robust image data resources is challenging and includes considerations of generation, curation, and storage of WSI files, and WSI access including via linked metadata. This opinion piece describes the collective experience of building resources for WSI data in the Roche group. We elaborate on the challenges encountered and solutions developed with the goal of providing examples of how to build a data resource for digital pathology analytics in the pharmaceutical industry.

Multiscale generative model using regularized skip-connections and perceptual loss for anomaly detection in toxicologic histopathology.

Background: Automated anomaly detection is an important tool that has been developed for many real-world applications, including security systems, industrial inspection, and medical diagnostics. Despite extensive use of machine learning for anomaly detection in these varied contexts, it is challenging to generalize and apply these methods to complex tasks such as toxicologic histopathology (TOXPATH) assessment (i.e.,finding abnormalities in organ tissues). In this work, we introduce an anomaly detection method using deep learning that greatly improves model generalizability to TOXPATH data. Methods: We evaluated a one-class classification approach that leverages novel regularization and perceptual techniques within generative adversarial network (GAN) and autoencoder architectures to accurately detect anomalous histopathological findings of varying degrees of complexity. We also utilized multiscale contextual data and conducted a thorough ablation study to demonstrate the efficacy of our method. We trained our models on data from normal whole slide images (WSIs) of rat liver sections and validated on WSIs from three anomalous classes. Anomaly scores are collated into heatmaps to localize anomalies within WSIs and provide human-interpretable results. Results: Our method achieves 0.953 area under the receiver operating characteristic on a real-worldTOXPATH dataset. The model also shows good performance at detecting a wide variety of anomalies demonstrating our method's ability to generalize to TOXPATH data. Conclusion: Anomalies in both TOXPATH histological and non-histological datasets were accurately identified with our method, which was only trained with normal data.

In vitro Insect Fat Cultivation for Cellular Agriculture Applications.

Cell-cultured fat could provide important elements of flavor, nutrition, and texture to enhance the quality and therefore expand consumer adoption of alternative meat products. In contrast to cells from livestock animals, insect cells have been proposed as a relatively low-cost and scalable platform for tissue engineering and muscle cell-derived cultured meat production. Furthermore, insect fat cells have long been cultured and characterized for basic biology and recombinant protein production but not for food production. To develop a food-relevant approach to insect fat cell cultivation and tissue engineering, Manduca sexta cells were cultured and induced to accumulate lipids in 2D and 3D formats within decellularized mycelium scaffolding. The resultant in vitro fat tissues were characterized and compared to in vivo fat tissue data by imaging, lipidomics, and texture analyses. The cells exhibited robust lipid accumulation when treated with a 0.1 mM soybean oil emulsion and had "healthier" fat profiles, as measured by the ratio of unsaturated to saturated fatty acids. Mycelium scaffolding provided a simple, food-grade approach to support the 3D cell cultures and lipid accumulation. This approach provides a low-cost, scalable, and nutritious method for cultured fat production.

Safety and Efficacy of Semorinemab in Individuals With Prodromal to Mild Alzheimer Disease: A Randomized Clinical Trial.

Importance: Neurofibrillary tangles composed of aggregated tau protein are one of the neuropathological hallmarks of Alzheimer disease (AD) and correlate with clinical disease severity. Monoclonal antibodies targeting tau may have the potential to ameliorate AD progression by slowing or stopping the spread and/or accumulation of pathological tau. Objective: To evaluate the safety and efficacy of the monoclonal anti-tau antibody semorinemab in prodromal to mild AD. Design, Setting, and Participants: This phase 2 randomized, double-blind, placebo-controlled, parallel-group clinical trial was conducted between October 18, 2017, and July 16, 2020, at 97 sites in North America, Europe, and Australia. Individuals aged 50 to 80 years (inclusive) with prodromal to mild AD, Mini-Mental State Examination scores between 20 and 30 (inclusive), and confirmed ß-amyloid pathology (by positron emission tomography or cerebrospinal fluid) were included. Interventions: During the 73-week blinded study period, participants received intravenous infusions of placebo or semorinemab (1500 mg, 4500 mg, or 8100 mg) every 2 weeks for the first 3 infusions and every 4 weeks thereafter. Main Outcomes and Measures: The primary outcomes were change from baseline on the Clinical Dementia Rating-Sum of Boxes score from baseline to week 73 and assessments of the safety and tolerability for semorinemab compared with placebo. Results: In the modified intent-to-treat cohort (n = 422; mean [SD] age, 69.6 [7.0] years; 235 women [55.7%]), similar increases were seen on the Clinical Dementia Rating-Sum of Boxes score in the placebo (n = 126; Δ = 2.19 [95% CI, 1.74-2.63]) and semorinemab (1500 mg: n = 86; Δ = 2.36 [95% CI, 1.83-2.89]; 4500 mg: n = 126; Δ = 2.36 [95% CI, 1.92-2.79]; 8100 mg: n = 84; Δ = 2.41 [95% CI, 1.88-2.94]) arms. In the safety-evaluable cohort (n = 441), similar proportions of participants experienced adverse events in the placebo (130 [93.1%]) and semorinemab (1500 mg: 89 [88.8%]; 4500 mg: 132 [94.7%]; 8100 mg: 90 [92.2%]) arms. Conclusions and Relevance: In participants with prodromal to mild AD in this randomized clinical trial, semorinemab did not slow clinical AD progression compared with placebo throughout the 73-week study period but did demonstrate an acceptable and well-tolerated safety profile. Additional studies of anti-tau antibodies may be needed to determine the clinical utility of this therapeutic approach. Trial Registration: ClinicalTrials.gov Identifier: NCT03289143.

Translational Approaches for Brain Delivery of Biologics via Cerebrospinal Fluid.

Delivery of biologics via cerebrospinal fluid (CSF) has demonstrated potential to access the tissues of the central nervous system (CNS) by circumventing the blood-brain barrier and blood-CSF barrier. Developing an effective CSF drug delivery strategy requires optimization of multiple parameters, including choice of CSF access point, delivery device technology, and delivery kinetics to achieve effective therapeutic concentrations in the target brain region, whereas also considering the biologic modality, mechanism of action, disease indication, and patient population. This review discusses key preclinical and clinical examples of CSF delivery for different biologic modalities (antibodies, nucleic acid-based therapeutics, and gene therapy) to the brain via CSF or CNS access routes (intracerebroventricular, intrathecal-cisterna magna, intrathecal-lumbar, intraparenchymal, and intranasal), including the use of novel device technologies. This review also discusses quantitative models of CSF flow that provide insight into the effect of fluid dynamics in CSF on drug delivery and CNS distribution. Such models can facilitate delivery device design and pharmacokinetic/pharmacodynamic translation from preclinical species to humans in order to optimize CSF drug delivery to brain regions of interest.

Antibody semorinemab reduces tau pathology in a transgenic mouse model and engages tau in patients with Alzheimer's disease.

Tau has become an attractive alternative target for passive immunotherapy efforts for Alzheimer's disease (AD). The anatomical distribution and extent of tau pathology correlate with disease course and severity better than other disease markers to date. We describe here the generation, preclinical characterization, and phase 1 clinical characterization of semorinemab, a humanized anti-tau monoclonal antibody with an immunoglobulin G4 (igG4) isotype backbone. Semorinemab binds all six human tau isoforms and protects neurons against tau oligomer neurotoxicity in cocultures of neurons and microglia. In addition, when administered intraperitoneally once weekly for 13 weeks, murine versions of semorinemab reduced the accumulation of tau pathology in a transgenic mouse model of tauopathy, independent of antibody effector function status. Semorinemab also showed clear evidence of target engagement in vivo, with increases in systemic tau concentrations observed in tau transgenic mice, nonhuman primates, and humans. Higher concentrations of systemic tau were observed after dosing in AD participants compared to healthy control participants. No concerning safety signals were observed in the phase 1 clinical trial at single doses up to 16,800 mg and multiple doses totaling 33,600 mg in a month.

LRRK2 inhibitors induce reversible changes in nonhuman primate lungs without measurable pulmonary deficits.

The kinase-activating mutation G2019S in leucine-rich repeat kinase 2 (LRRK2) is one of the most common genetic causes of Parkinson's disease (PD) and has spurred development of LRRK2 inhibitors. Preclinical studies have raised concerns about the safety of LRRK2 inhibitors due to histopathological changes in the lungs of nonhuman primates treated with two of these compounds. Here, we investigated whether these lung effects represented on-target pharmacology and whether they were reversible after drug withdrawal in macaques. We also examined whether treatment was associated with pulmonary function deficits. We conducted a 2-week repeat-dose toxicology study in macaques comparing three different LRRK2 inhibitors: GNE-7915 (30 mg/kg, twice daily as a positive control), MLi-2 (15 and 50 mg/kg, once daily), and PFE-360 (3 and 6 mg/kg, once daily). Subsets of animals dosed with GNE-7915 or MLi-2 were evaluated 2 weeks after drug withdrawal for lung function. All compounds induced mild cytoplasmic vacuolation of type II lung pneumocytes without signs of lung degeneration, implicating on-target pharmacology. At low doses of PFE-360 or MLi-2, there was ~50 or 100% LRRK2 inhibition in brain tissue, respectively, but histopathological lung changes were either absent or minimal. The lung effect was reversible after dosing ceased. Lung function tests demonstrated that the histological changes in lung tissue induced by MLi-2 and GNE-7915 did not result in pulmonary deficits. Our results suggest that the observed lung effects in nonhuman primates in response to LRRK2 inhibitors should not preclude clinical testing of these compounds for PD.

Mechanistic Modeling of Soluble Aß Dynamics and Target Engagement in the Brain by Anti-Aß mAbs in Alzheimer's Disease.

BACKGROUND: Anti-amyloid-ß (Aß) monoclonal antibodies (mAbs) are currently in development for treating Alzheimer's disease. OBJECTIVES: To address the complexity of Aß target engagement profiles, improve the understanding of crenezumab Pharmacokinetics (PK) and Aß Pharmacodynamics (PD) in the brain, and facilitate comparison of anti-Aß therapies with different binding characteristics. METHODS: A mechanistic mathematical model was developed describing the distribution, elimination, and binding kinetics of anti-Aß mAbs and Aß (monomeric and oligomeric forms of Aß1-40 and Aß1-42) in the brain, Cerebrospinal Fluid (CSF), and plasma. Physiologically meaningful values were assigned to the model parameters based on the previous data, with remaining parameters fitted to clinical measurements of Aß concentrations in CSF and plasma, and PK/PD data of patients undergoing anti-Aß therapy. Aß target engagement profiles were simulated using a Monte Carlo approach to explore the impact of biological uncertainty in the model parameters. RESULTS: Model-based estimates of in vivo affinity of the antibody to monomeric Aß were qualitatively consistent with the previous data. Simulations of Aß target engagement profiles captured observed mean and variance of clinical PK/PD data. CONCLUSION: This model is useful for comparing target engagement profiles of different anti-Aß therapies and demonstrates that 60 mg/kg crenezumab yields a significant increase in Aß engagement compared with lower doses of solanezumab, supporting the selection of 60 mg/kg crenezumab for phase 3 studies. The model also provides evidence that the delivery of sufficient quantities of mAb to brain interstitial fluid is a limiting step with respect to the magnitude of soluble Aß oligomer neutralization.

Cáncer de mama y virus, sí pero no / Breast cancer and virus, yes but no

El cáncer de mama es el que con más frecuecia afecta a las mujeres. Aunque no se ha podido todavía establecer una causa asociada a esta neoplasia, sí se conocen ciertos factores que podrían favorecer este proceso. Se ha investigado la presencia de algunos virus oncogénicos en el cáncer de mama (virus del papiloma humano, virus del tumor mamario del ratón y el virus de Epstein-Barr). Las técnicas moleculares actuales no permiten aplicar los postulados de Koch. Mediante las técnicas moleculares convencionales se ha podido detectar la presencia de estos virus en el 0-86% de los tejidos tumorales mamarios; sin embargo, no se ha mostrado evidencia de la transcripción activa de los genes virales en estos tejidos. Partiendo del criterio de que concentraciones de transcriptos inferiores a 2 ppm son inconsistentes con la participación de un determinado virus, puede concluirse que no existe actualmente ninguna evidencia científica de que un virus conocido esté implicado

Breast cancer is the most common cancer that affects women. Although it is known that certain factors favour this process, it has not yet been possible to establish a cause associated with this neoplasm. The presence of some oncogenic viruses in breast cancer, such as such as human papillomavirus), mouse mammary tumour virus, and Epstein-Barr virus, has been investigated. The Koch postulates cannot be applied with current molecular techniques. Although using conventional molecular techniques it has been possible to detect the presence of these viruses in between 0-86% of breast tumour tissues. However, no evidence of active transcription of the viral genes in these tissues has been demonstrated. Based on the criterion that transcript concentrations lower than 2ppm are inconsistent with the participation of a certain virus, it can be concluded that there is currently no scientific evidence that a known virus is involved

Characterization of the selective in vitro and in vivo binding properties of crenezumab to oligomeric Aß.

BACKGROUND: Accumulation of amyloid ß (Aß) in the brain is proposed as a cause of Alzheimer's disease (AD), with Aß oligomers hypothesized to be the primary mediators of neurotoxicity. Crenezumab is a humanized immunoglobulin G4 monoclonal antibody that has been shown to bind to synthetic monomeric and aggregated Aß in vitro; however, less is known about the binding characteristic in vivo. In this study, we evaluated the binding patterns of crenezumab to synthetic and native forms of Aß both in vitro and in vivo. METHODS: Crenezumab was used to immunoprecipitate Aß from synthetic Aß preparations or brain homogenates from a PS2APP mouse model of AD to determine the forms of Aß that crenezumab interacts with. Following systemic dosing in PS2APP or nontransgenic control mice, immunohistochemistry was used to localize crenezumab and assess its relative distribution in the brain, compared with amyloid plaques and markers of neuritic dystrophies (BACE1; LAMP1). Pharmacodynamic correlations were performed to investigate the relationship between peripheral and central target engagement. RESULTS: In vitro, crenezumab immunoprecipitated Aß oligomers from both synthetic Aß preparations and endogenous brain homogenates from PS2APP mice. In vivo studies in the PS2APP mouse showed that crenezumab localizes to regions surrounding the periphery of amyloid plaques in addition to the hippocampal mossy fibers. These regions around the plaques are reported to be enriched in oligomeric Aß, actively incorporate soluble Aß, and contribute to Aß-induced neurotoxicity and axonal dystrophy. In addition, crenezumab did not appear to bind to the dense core region of plaques or vascular amyloid. CONCLUSIONS: Crenezumab binds to multiple forms of amyloid ß (Aß), particularly oligomeric forms, and localizes to brain areas rich in Aß oligomers, including the halo around plaques and hippocampal mossy fibers, but not to vascular Aß. These insights highlight a unique mechanism of action for crenezumab of engaging Aß oligomers.

Lumbar fusion involving the sacrum increases dislocation risk in primary total hip arthroplasty.

AIMS: Concurrent hip and spine pathologies can alter the biomechanics of spinopelvic mobility in primary total hip arthroplasty (THA). This study examines how differences in pelvic orientation of patients with spine fusions can increase the risk of dislocation risk after THA. PATIENTS AND METHODS: We identified 84 patients (97 THAs) between 1998 and 2015 who had undergone spinal fusion prior to primary THA. Patients were stratified into three groups depending on the length of lumbar fusion and whether or not the sacrum was involved. Mean age was 71 years (40 to 87) and 54 patients (56%) were female. The mean body mass index (BMI) was 30 kg/m2 (19 to 45). Mean follow-up was six years (2 to 17). Patients were 1:2 matched to patients with primary THAs without spine fusion. Hazard ratios (HR) were calculated. RESULTS: Dislocation in the fusion group was 5.2% at one year versus 1.7% in controls but this did not reach statistical significance (HR 1.9; p = 0.33). Compared with controls, there was no significant difference in rate of dislocation in patients without a sacral fusion. When the sacrum was involved, the rate of dislocation was significantly higher than in controls (HR 4.5; p = 0.03), with a trend to more dislocations in longer lumbosacral fusions. Patient demographics and surgical characteristics of THA (i.e. surgical approach and femoral head diameter) did not significantly impact risk of dislocation (p > 0.05). Significant radiological differences were measured in mean anterior pelvic tilt between the one-level lumbar fusion group (22°), the multiple-level fusion group (27°), and the sacral fusion group (32°; p < 0.01). Ten-year survival was 93% in the fusion group and 95% in controls (HR 1.2; p = 0.8). CONCLUSION: Lumbosacral spinal fusions prior to THA increase the risk of dislocation within the first six months. Fusions involving the sacrum with multiple levels of lumbar involvement notably increased the risk of postoperative dislocation compared with a control group and other lumbar fusions. Surgeons should take care with component positioning and may consider higher stability implants in this high-risk cohort.

[Baloxavir marboxil: a potent cap-dependent endonuclease inhibitor of influenza viruses]. / Baloxavir marboxil: un potente inhibidor de la endonucleasa cap-dependiente de los virus gripales.

Baloxavir marboxil (5-hydroxy-4-pyridone-3-carboxyl acid) is a new antiviral drug with special efficacy on influenza viruses that acts by inhibiting the cap-dependent endonuclease required for its replication. It is the first representative of the so-called inhibitors of influenza-like PB2. It has shown efficacy against influenza viruses A and B and most strains of animal origin (avian flu). Clinical trials conducted in healthy patients between 12 and 64 years without pathologies and not hospitalized (mild flu) have shown a reduction in the duration of symptoms similar to that obtained by oseltamivir. However, baloxavir is a much more potent inhibitor of viral replication than this drug. It has been shown as a safe and well tolerated drug. A single dose of 40-80 mg is administered the first 48 hours after onset of symptoms. In these trials, strains with moderate sensitivity (PA / I38T mutants) were detected in 2.2% of influenza A (H1N1) pdm09 and in 9.7% of influenza A (H3N2). Although these data could be a good drug to treat mild or moderate influenza, requiring trials in severe influenza and patients with chronic diseases to establish their true clinical utility.

Amyloid positron emission tomography and cerebrospinal fluid results from a crenezumab anti-amyloid-beta antibody double-blind, placebo-controlled, randomized phase II study in mild-to-moderate Alzheimer's disease (BLAZE).

BACKGROUND: We investigated the effect of crenezumab, a humanized anti-amyloid-beta (Aß) immunoglobulin (Ig)G4 monoclonal antibody, on biomarkers of amyloid pathology, neurodegeneration, and disease progression in patients with mild-to-moderate Alzheimer's disease (AD). METHODS: This double-blind, placebo-controlled, randomized phase II study enrolled patients with mild-to-moderate AD and a Mini-Mental State Examination (MMSE) score of 18-26. In part 1 of the study, patients were 2:1 randomized to receive low-dose subcutaneous (SC) 300 mg crenezumab every 2 weeks (q2w) or placebo for 68 weeks; in part 2, patients were 2:1 randomized to receive high-dose intravenous (IV) 15 mg/kg crenezumab every 4 weeks (q4w) or placebo for 68 weeks. The primary endpoint was change in amyloid burden from baseline to week 69 assessed by florbetapir positron emission tomography (PET) in the modified intent-to-treat population. Secondary endpoints were change from baseline to week 69 in cerebrospinal fluid (CSF) biomarkers and fluorodeoxyglucose PET, and change from baseline to week 73 in 12-point Alzheimer's Disease Assessment Scale cognitive subscale (ADAS-Cog12) and Clinical Dementia Rating Sum of Boxes (CDR-SB). Safety was assessed in patients who received at least one dose of study treatment. RESULTS: From August 2011 to September 2012, 91 patients were enrolled and randomized (low-dose SC cohort: crenezumab (n = 26) or placebo (n = 13); high-dose IV cohort: crenezumab (n = 36) or placebo (n = 16)). The primary endpoint was not met using a prespecified cerebellar reference region to calculate standard uptake value ratios (SUVRs) from florbetapir PET. Exploratory analyses using subcortical white matter reference regions showed nonsignificant trends toward slower accumulation of plaque amyloid in the high-dose IV cohort. In both cohorts, a significant mean increase from baseline in CSF Aß(1-42) levels versus placebo was observed. Nonsignificant trends toward ADAS-Cog12 and CDR-SB benefits were identified in a mild (MMSE 20-26) subset of the high-dose IV cohort. No amyloid-related imaging abnormalities due to edema/effusion were observed. CONCLUSION: The primary endpoint was not met. Exploratory findings suggest potential Aß target engagement with crenezumab and possible slower accumulation of plaque amyloid. Studies investigating the effects of higher doses of crenezumab on amyloid load and disease progression are ongoing. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01397578 . Registered on 18 July 2011.

An automated mapping method for Nissl-stained mouse brain histologic sections.

BACKGROUND: Histologic evaluation of the central nervous system is often a critical endpoint in in vivo efficacy studies, and is considered the essential component of neurotoxicity assessment in safety studies. Automated image analysis is a powerful tool that can radically reduce the workload associated with evaluating brain histologic sections. NEW METHOD: We developed an automated brain mapping method that identifies neuroanatomic structures in mouse histologic coronal brain sections. The method utilizes the publicly available Allen Brain Atlas to map brain regions on digitized Nissl-stained sections. RESULTS: The method's accuracy was first assessed by comparing the mapping results to structure delineations from the Franklin and Paxinos (FP) mouse brain atlas. Brain regions mapped from FP Nissl-stained sections and calculated volumes were similar to structure delineations and volumes derived from corresponding FP illustrations. We subsequently applied our method to mouse brain sections from an in vivo study where the hippocampus was the structure of interest. Nissl-stained sections were mapped and hippocampal boundaries transferred to adjacent immunohistochemically stained sections. Optical density quantification results were comparable to those from time-consuming, manually drawn hippocampal delineations on the IHC-stained sections. COMPARISON WITH EXISTING METHODS: Compared to other published methods, our method requires less manual input, and has been validated comprehensively using a secondary atlas, as well as manually annotated brain IHC sections from 68 study mice. CONCLUSIONS: We propose that our automated brain mapping method enables greater efficiency and consistency in mouse neuropathologic assessments.

ABBY: A phase 2 randomized trial of crenezumab in mild to moderate Alzheimer disease.

OBJECTIVE: To evaluate the safety and efficacy of crenezumab in patients with mild to moderate Alzheimer disease (AD). METHODS: In this phase 2 trial, 431 patients with mild to moderate AD 50 to 80 years of age were randomized 2:1 (crenezumab:placebo). Patients received low-dose subcutaneous crenezumab 300 mg or placebo every 2 weeks (n = 184) or high-dose intravenous crenezumab 15 mg/kg or placebo every 4 weeks (n = 247) for 68 weeks. Primary outcome measures were change in Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog12) and Clinical Dementia Rating-Sum of Boxes scores from baseline to week 73. RESULTS: The primary and secondary endpoints were not met. In an exploratory post hoc analysis, a reduction in decline on the ADAS-Cog12 was observed in the high-dose group. Separation from the placebo group on the ADAS-Cog12 was greatest in the milder subsets of AD patients and reached statistical significance in the group with Mini-Mental State Examination scores of 22 to 26. In both groups, there was a significant increase in CSF ß-amyloid1-42 levels that correlated with crenezumab CSF levels. The overall rate of adverse events was balanced between groups. One case of amyloid-related imaging abnormalities indicative of vasogenic edema or effusions was reported. CONCLUSIONS: Although prespecified criteria for testing treatment effects were not met, these data suggest a potential treatment effect in patients with mild AD treated with high-dose crenezumab. Together with the safety profile for crenezumab, these data support the exploration of crenezumab treatment at even higher doses in patients with early AD. CLINICALTRIALSGOV IDENTIFIER: NCT 01343966. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, for people with AD, crenezumab does not significantly improve cognition or function at 18 months. The study is rated Class II because <80% of enrolled patients completed the study.

The CJOrtho app: A mobile clinical and educational tool for orthopedics.

The need for modern patient evaluation tools continues to grow. A dependable and reproducible assessment provides objective follow-up and increases the validity of collected data. This is where mobile apps come into play, as they provide a link between surgeons and patients. They also open the possibility of interacting with other healthcare staff to exchange common scientific reference systems and databases. The CJOrtho app provides fast access to 65 classification systems in orthopedics or trauma surgery, 20 clinical outcome scores and a digital goniometer. The development of free mobile apps is an opportunity for education and better follow-up, while meeting the demands of patients.