Transcranial Photobiomodulation of Clearance of Beta-Amyloid from the Mouse Brain: Effects on the Meningeal Lymphatic Drainage and Blood Oxygen Saturation of the Brain

Here, we demonstrate the therapeutic effects of transcranial photobiomodulation (tPBM, 1267 nm, 32 J/cm2, a 9-day course) in mice with the injected model of Alzheimer's disease (AD) associated with accumulation of beta-amyloid (Aβ) in the brain resulting in neurocognitive deficit vs. the control group (CG) (the neurological severity score (NNS), AD 3.67 ± 0.58 vs. CG 1.00 ± 0.26%, p < 0.05) and mild cerebral hypoxia (AD 72 ± 6% vs. CG 97 ± 2%, p < 0.001). The course of tPBM improved neurocognitive status of mice with AD (NNS, AD 2.03 ± 0.14 vs. CG 1.00 ± 0.26, vs. 2.03 ± 0.14, p < 0.05) due to stimulation of clearance of Aβ from the brain via the meningeal lymphatic vessels (the immunohistochemical and confocal data) and an increase in blood oxygen saturation of the brain tissues (the pulse oximetry data) till 85 ± 2%, p < 0.05. These results open breakthrough strategies for non-pharmacological therapy of AD and clearly demonstrate that tPBM might be a promising therapeutic target for preventing or delaying AD based on stimulation of oxygenation of the brain tissues and activation of clearance of toxic molecules via the cerebral lymphatics.

The macromolecular architecture of platelet-derived microparticles

Platelets are essential for hemostasis and wound healing. They are involved in fundamental processes of vascular biology such as angiogenesis, tissue regeneration, and tumor metastasis. Upon activation, platelets shed small plasma membrane vesicles termed platelet-derived microparticles (PMPs). PMPs include functional cell adhesion machinery that comprises transmembrane receptors (most abundant are the αIIbβ3 integrins), cytoskeletal systems and a large variety of adapter and signaling molecules. Glanzmann thrombasthenia (GT) is a condition characterized by platelets that are deficient of the integrin αIIbβ3 heterodimer. Here, we use cryo-electron tomography (cryo-ET) to study the structural organization of PMPs (in both healthy and GT patients), especially the cytoskeleton organization and receptor architecture. PMPs purified from GT patients show a significantly altered cytoskeletal organization, characterized by a reduced number of filaments present, compared to the healthy control. Furthermore, our results show that incubating healthy PMPs with manganese ions (Mn(2+)), in the presence of fibrinogen, induces a major conformational change of integrin receptors, whereas thrombin activation yields a moderate response. These results provide the first insights into the native molecular organization of PMPs.

[Intraneural cysts of the peroneal nerve in childhood: report of 2 cases and literature review]

Intraneural cysts are benign lesions filled with mucinous content and located inside the epineurum of the peripheral nerves. Peroneal nerve is the most affected nerve. The entity is rare and its ethiopathology still remains to be definitely elucidated. In 2003 Spinner et al published their articular theory, implicated in the formation and frequent recurrence of these lesions after surgical treatment. The practical application of this theory, nowadays almost universally accepted, generated an important diminution in the recurrence rate after surgical evacuation of this lesions, previously very elevated. Most of the cases of this entity are described in adults. In the present paper we describe two pediatric cases and analyze the clinical aspects of these cysts in pediatric and adults patients. Peroneal intraneural cysts are one of the differential diagnoses in foot drop, and an adequate treatment concludes in a complete remission of the symptoms.

Eukaryotic expression: developments for structural proteomics

The production of sufficient quantities of protein is an essential prelude to a structure determination, but for many viral and human proteins this cannot be achieved using prokaryotic expression systems. Groups in the Structural Proteomics In Europe (SPINE) consortium have developed and implemented high‐throughput (HTP) methodologies for cloning, expression screening and protein production in eukaryotic systems. Studies focused on three systems: yeast (Pichia pastoris and Saccharomyces cerevisiae), baculovirus‐infected insect cells and transient expression in mammalian cells. Suitable vectors for HTP cloning are described and results from their use in expression screening and protein‐production pipelines are reported. Strategies for co‐expression, selenomethionine labelling (in all three eukaryotic systems) and control of glycosylation (for secreted proteins in mammalian cells) are assessed.

Subclinical sensory abnormalities in trigeminal neuralgia

Trigeminal neuralgia is considered as a paroxysmal single nerve phenomenon. Abnormal sensory perception has been previously described in 15-25% of patients with clinical examination. Quantitative sensory testing (QST) was used to evaluate sensory perception in patients with idiopathic trigeminal neuralgia (ITN). Nine patients and 10 normal control subjects were evaluated in all six trigeminal branches. QST abnormalities were found in the symptomatic division and in the other two branches on the same side. Minor contralateral changes were also found. Differences consisted of cold and warm hypoaesthesia and higher cold and heat pain thresholds in patients. All differences proved statistically significant. Our findings suggest that trigeminal neuralgia is not only a paroxysmal single nerve disorder, but also that other higher structures may be involved.

Merosin-deficient congenital muscular dystrophy associated with abnormal cerebral cortical gyration: an autopsy study

We report clinical, biopsy and autopsy findings in a merosin-deficient congenital muscular dystrophy (CMD) infant with abnormal cortical gyration. Brain showed polymicrogyria and occipital agyria with marginal neuroglial heterotopia and inferior vermis hypoplasia. There was a normal pattern of myelination consistent with early age. Laminin alpha 2 chain was also absent in myocardium, brain pial-glial membrane, brain and skin blood vessels as well as intramuscular and skin nerves. Occasional basal lamina gaps were found in muscle fibres but not in brain-blood vessels. This is the first autopsy study in a merosin-deficient CMD case with abnormal cortical gyration.

Reinnervation in Duchenne muscular dystrophy

Motor neuron abnormalities have been implicated in the pathogenesis of Duchenne muscular dystrophy. Evidence concerning the effect of injury on motor neurons of human Duchenne muscular dystrophy (DMD) is lacking. We report a DMD patient having, in addition, an obstetric paresis on his left arm. EMG and muscle histochemistry showed signs of reinnervation superimposed on myopathy in his left arm. This suggests that sprouting is preserved in DMD motor neurons and that muscle fibers retain the capability of accepting reinnervation.

Distal spinal muscular atrophy and ophthalmoparesis. A case with selective type 2 fiber hypotrophy

A patient had distal muscular atrophy involving the upper and lower extremities, ptosis of the lid, and ophthalmoparesis and cataracts. Muscle histochemistry and electromyographic examination showed lower motor neuron involvement. This case is similar to others described in the literature and designated as distal spinal muscular atrophy. The unique association with ophthalmologic signs can be considered either as a variant form of the disease or as a separate entity. Muscle biopsy showed selective type 2 muscle fiber hypotrophy in the biceps. A second biopsy specimen of the quadriceps showed type grouping with persistence of small type 2 fibers, suggesting that reinnervation capability is independent of neuronal trophic influence.