Meningeal‐like organization of neural tissues in calanoid copepods (Crustacea)

Meninges, the connective tissue of the vertebrate central nervous system (CNS), have not been recognized in invertebrates. We describe the ultrastructure of the adult brain, antennules, and cord in five marine copepods: Calanus finmarchicus, Gaussia princeps, Bestiolina similis, Labidocera madurae, and Euchaeta rimana. In all of these locations we identified cell types with characteristics of the typical cells of vertebrate meninges and of their peripheral nervous system (PNS) connective tissue counterpart: fibroblasts, having flattened twisting processes with labyrinthine cavities communicating with the extracellular space, and macrophages, containing prominent lysosomes, well‐developed endoplasmic reticulum, Golgi apparatus, and indented heterochromatin. The vertebrate distinction between electron‐dense cells in the most external connective tissues (dura mater and epineurium) versus electron‐lucent cells in the more internal connective tissues (pia‐arachnoid and endoneurium‐perineurium) was also found in the copepod CNS and PNS. Similar to the vertebrate organization, electron‐dense cell networks penetrated from the outer layer (subcuticle) to surround inner substructures of the copepod nervous systems, and electron‐lucent networks penetrated deeply from the brain and nerve surfaces to form intertwined associations with neural cells. Moreover, the association of these cells with basement membranes, glycocalyx, and fibrils of collagen in copepods conforms to a meningeal organization. The primary deviation from the vertebrate ultrastructural organization was the often tight investment of axons by the meningeal‐like cells, with an intercalated basement membrane. Together, these data suggest that the tissues investing the copepod nervous system possess an organization that is analogous in many respects to that of vertebrate meninges. J. Comp. Neurol. 521:760–790, 2013. © 2012 Wiley Periodicals, Inc.     

Quantitative assessment of interradicular bone density in the maxilla and mandible: implications in clinical orthodontics

Background

Bone density at the interradicular area plays an important role during orthodontic treatment. In view of this fact, the study was designed to quantitatively evaluate the bone density at the interradicular areas of the alveolar and basal bones of maxilla and mandible by computed tomography.

Methods

One hundred and nine computed tomographic images were randomly selected, and bone density was measured in Hounsfield units (HU) with bone mineral density software (Siemens VA20A_SP3A). The sample consisted of 78 males (mean age 29.5 years, range 20 to 40 years) and 31 females (mean age 27.6 years, range 20 to 40 years). Cortical and cancellous bone density was measured at the interradicular areas at the alveolar and basal bone levels of the maxilla and mandible, and the data was subjected to statistical analysis for comparisons.

Results

The highest cortical bone density was observed between the second premolar and first molar at the alveolar bone level and between the first and second molars at the basal bone level in the maxilla. Maxillary tuberosity showed the least bone density. The density of the cortical bone was greater in the mandible than in the maxilla and showed a progressive increase from the incisor to the retromolar area. The basal bone showed a higher density thanthe alveolar bone.

Conclusion

Different qualities of the bone were found in the anatomic regions studied, which confirms the importance of knowledge of site-specific bone tissue density to correlate with various clinical findings.     

Muscle phenotype in patients with myotonic dystrophy type 1

Introduction: The pathogenesis of muscle involvement in patients with myotonic dystrophy type 1 (DM1) is not well understood. In this study, we characterized the muscle phenotype in patients with confirmed DM1. Methods: In 38 patients, muscle strength was tested by hand‐held dynamometry. Myotonia was evaluated by a handgrip test and by analyzing the decrement of the compound muscle action potential. Muscle biopsies were assessed for morphological changes and Na⁺‐K⁺ pump content. Results: Muscle strength correlated with a decline in Na⁺‐K⁺ pump content (r = 0.60, P < 0.001) and with CTG expansion. CTG expansion did not correlate with severity of myotonia, proximal histopathological changes, or Na⁺‐K⁺ pump content. Histopathologically, we found few centrally placed nuclei (range 0.2–6.9%). Conclusions: The main findings of this study are that muscle weakness correlated inversely with CTG expansion and that central nuclei are not a prominent feature of proximal muscles in DM1. Muscle Nerve 47:409‐415, 2013     

Development and Psychometric Properties of a Computer-Based Standardized Emotional Competence Inventory (MeKKi) for Preschoolers and School-Aged Children

Child Psychiatry & Human Development - A computer-based emotional competence inventory for preschoolers and school-aged children (MeKKi) was developed to assess five components of emotional...     

In vivo evaluation of PEGylated <Superscript>64</Superscript>Cu-liposomes with theranostic and radiotherapeutic potential using micro PET/CT

Purpose

The objective of this study was to evaluate the potential of PEGylated ⁶⁴Cu-liposomes in clinical diagnostic positron emission tomography (PET) imaging and PEGylated ¹⁷⁷Lu-liposomes in internal tumor radiotherapy through in vivo characterization and dosimetric analysis in a human xenograft mouse model.

Methods

Liposomes with 5 and 10 mol% PEG were characterized with respect to size, charge, and ⁶⁴Cu- and ¹⁷⁷Lu-loading efficiency. The tumor imaging potential of ⁶⁴Cu-loaded liposomes was evaluated in terms of in vivo biodistribution, tumor accumulation and tumor-to-muscle (T/M) ratios, using PET imaging. The potential of PEGylated liposomes for diagnostic and therapeutic applications was further evaluated through dosimetry analysis using OLINDA/EXM software. The ⁶⁴Cu-liposomes were used as biological surrogates to estimate the organ and tumor kinetics of ¹⁷⁷Lu-liposomes.

Results

High remote loading efficiency (>95 %) was obtained for both ⁶⁴Cu and ¹⁷⁷Lu radionuclides with PEGylated liposomes, and essentially no leakage of the encapsulated radionuclide was observed upon storage and after serum incubation for 24 h at 37 °C. The 10 mol% PEG liposomes showed higher tumor accumulation (6.2?±?0.2 %ID/g) than the 5 mol% PEG liposomes, as evaluated by PET imaging. The dosimetry analysis of the ⁶⁴Cu-liposomes estimated an acceptable total effective dose of 3.3·10^?2 mSv/MBq for diagnostic imaging in patients. A high absorbed tumor dose (114 mGy/MBq) was estimated for the potential radiotherapeutic ¹⁷⁷Lu-liposomes.

Conclusion

The overall preclinical profile of PEGylated ⁶⁴Cu-liposomes showed high potential as a new PET theranostic tracer for imaging in humans. Dosimetry results predicted that initial administered activity of 200 MBq of ⁶⁴Cu-liposomes should be acceptable in patients. Work is in progress to validate the utility of PEGylated ⁶⁴Cu-liposomes in a clinical research programme. The high absorbed tumor dose (114 mGy/MBq) estimated for ¹⁷⁷Lu-liposomes and the preliminary dosimetric studies justify further therapeutic and dosimetry investigation of ¹⁷⁷Lu-liposomes in animals before potential testing in man.

     

The effect of rater training on scoring performance and scale-specific expertise amongst occupational therapists participating in a multicentre study: a single-group pre–post-test study

Purpose: In order to enhance the quality of the data collected in a multicentre validation study of a revised Danish version of the McGill Ingestive Skills Assessment (MISA), the authors developed a rater training programme. The purpose of the present study was to evaluate the effect of the training on scoring performance and scale-specific expertise amongst raters. Method: During 2 days of rater training, 81 occupational therapists (OTs) were qualified to observe and score dysphagic clients’ mealtime performance according to the criteria of 36 MISA-items. The training effects were evaluated pre- to post-training using percentage exact agreement (PA) of scored MISA items of a case-vignette and a Likert scale self-report of scale-specific expertise. Results: PA increased significantly from pre- to post-training (Z = ?4.404, p < 0.001), although items for which the case-vignette reflected deficient mealtime performance appeared most difficult to score. The OTs scale-specific expertise improved significantly (knowledge: Z = ?7.857, p < 0.001 and confidence: Z = ?7.838, p < 0.001). Conclusion: Rater training improved OTs scoring performance when using the Danish MISA as well as their perceived scale-specific expertise. Future rater training should emphasis the items identified as those most difficult to score. Additionally, further studies addressing different training approaches and durations are warranted.

• Implications for Rehabilitation

• When occupational therapists (OTs) use the McGill Ingestive Skills Assessment (MISA) they observe, interpret and record occupational performance of dysphagic clients participating in a meal. This is a highly complex task, which might introduce unwanted variability in measurement scores.

• A 2-day rater training programme was developed and this builds on the findings of several studies. These suggest that combinations of different training methods tend to yield the most effective results.

• Participation in the newly developed training programme on how to administer the MISA significantly reduces unwanted variability in measurement scores and improves OTs’ competency.

• The training programme could be used in undergraduate and postgraduate dysphagia education initiatives to help OTs understanding of the content and the scoring criteria for each aspect of occupational performance during a meal, thus developing observation skills as well as recognizing and avoiding the most common errors in measurement scores.

     

Ficolin-2 recognizes DNA and participates in the clearance of dying host cells

Ficolin-2 is a serum opsonin, which has been shown to be a pattern recognition molecule in the lectin complement activation pathway. Because innate immune mechanisms are involved in maintaining tissue homeostasis we hypothesized that Ficolin-2 also participate in the clearance of dying host cells. We found that Ficolin-2 binds to late apoptotic cells, as well as to apoptotic bodies and necrotic cells, but not to early apoptotic cells. We demonstrated that Ficolin-2 binds DNA in a calcium dependent manner and that DNA inhibits the binding to late apoptotic and necrotic cells, suggesting that DNA on permeable dying cells is a plausible ligand. Reconstituting serum deficient of Ficolin-2, C1q and mannose-binding lectin with Ficolin-2 augmented deposition of complement C4 on necrotic cells. Opsonization leads to an enhanced attachment/uptake of necrotic cells by macrophages. In conclusion dying host cells expose ligands with the capacity of binding Ficolin-2, which in turn leads to increased attachment and engulfment. Binding of Ficolin-2 to DNA points at nucleic acid exposed by permeable late apoptotic and necrotic cells as one of the ligands for Ficolin-2. Ficolin-2 may therefore be a scavenger molecule participating in the removal of host cells and maintenance of tissue homeostasis.