Technical aspects and current clinical applications of the skin and skeletal muscle biopsy in neurological diagnostics: an overview.

This short overview recalls the basic principles and technical aspects of skin and skeletal muscle biopsies in humans with paying special attention to the stages of these procedures essential for further correct morphological diagnosis. Some of these principles may also be useful in animal experimental studies. The authors emphasize the important role of proper thickness of the skin fragment, proper orientation of muscle fibres and a scalpel during skin biopsy, and proper concentration of fixatives. They recommend avoiding anaesthesia of the skeletal muscle itself and using forceps carefully so as not to crush the epidermis.

The spectrum of microvascular ultrastructural changes in the subpopulation of patients with migraine and cerebral white matter hyperintensities on MRI.

INTRODUCTION: Migraine is considered not only as a separate clinical entity but also as a symptom of various brain disorders, including cerebral small vessel diseases. Since cerebral small vessel diseases are usually general angiopathies, evaluation of biopsy material other than brain tissue may help in their diagnosis in vivo. In patients with migraine, brain magnetic resonance imaging (MRI) often shows hyperintense changes in the cerebral white matter. Such changes may indicate the symptomatic nature of migraine and coexisting structural or biochemical vascular abnormalities. MATERIAL AND METHODS: To verify the hypothesis of the symptomatic nature of migraine in patients with abnormal brain neuroimaging, we performed an ultrastructural examination of skin and skeletal muscle vessels in biopsy material from 40 patients with clinically diagnosed migraine and hyperintense white matter lesions on MRI. RESULTS: In 80% of the examined patients, ultrastructural examination showed various pathological changes in the microvessels including abnormalities characteristic of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and elastin disorders, as well as less specific changes such as thickening of the basal lamina, narrowing of the vessel lumen, degeneration of the vessel wall cells, endothelial activation, oncosis-like changes, and the presence of various types of deposits in the vessel wall. In 20% of the examined cases, ultrastructural examination of the vessels was normal. CONCLUSIONS: Patients with migraine and hyperintense cerebral white matter changes on MRI have an increased risk of concomitant microangiopathy. In this group of patients, skin-muscle biopsy allows the identification of cases with coexisting vessel abnormalities.

Diplomyelia in a patient with a clinical suspicion of autosomal recessive spastic ataxia of Charlevoix-Saguenay type (ARSACS).

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a form of cerebellar ataxia related to mutations in the SACS gene on chromosome 13q12.12 encoding sacsin protein. Characteristic clinical features are ataxia, spasticity, distal muscle wasting, neuropathy, dysarthria, nystagmus, and finger or feet deformities. The presented case concerns a 32-year-old man with clinical diagnosis of ARSACS. Magnetic resonance imaging (MRI) scans of the brain revealed cerebellar atrophy typical of the disease while neuroimaging of the C1-C3 and C6-Th12 segments showed only the thin thoracic spinal cord. The patient died suddenly and a gross examination of the spinal cord revealed extraspinal tumour at the C4-C5 levels, which turned out to be an additional spinal cord. Microscopic examination showed an extensive ischemic necrosis involving C6-Th5 segments of the proper spinal cord, and disturbed intrinsic structure containing many pathological vessels of the extra spinal cord. Lack of visualization of C4-C5 spinal cord segments on MRI scans made diagnosis of diplomyelia in vivo impossible. However, diplomyelia does not exclude coexistence of ARSACS because of the occurrence of such clinical symptoms as dysarthria or nystagmus which cannot be explained by the presence of the spinal cord defect. The possibility of congenital malformations of the spinal cord in adults should be remembered as their early identification and surgical correction can improve neurological symptoms.

Neuropathological Findings in Ephedrone Encephalopathy.

BACKGROUND: A number of cases of severe parkinsonism-dystonia have been recognized and reported following the illicit use of ephedrone prepared from pseudoephedrine and potassium permanganate. The pathology associated with ephedrone neurotoxicity has not been described yet in the scientific literature. OBJECTIVES: To report the first neuropathological study of ephedrone toxicity. METHODS: The brain of a 33-year-old Ukrainian female ex-ephedrone addict with a long history of l-dopa-unresponsive parkinsonism with dysarthria, dystonia, profound postural instability, cock-gait, and frequent falls, and on antiretroviral treatment, was examined using routine stains and immunohistochemistry. RESULTS: Neuropathological findings included diffuse pallidal astrogliosis without neuronal depletion. There was also widespread vascular pathology with small vessels occluded by foreign material, associated with giant cell response without any evidence of consequent focal infarction and a cerebellar abscess. CONCLUSIONS: Clinical findings of l-dopa-unresponsive parkinsonism with dystonia, caused by illicit use of ephedrone, are fully consistent with neuropathological changes in the pallidum, lack of change in the SN, and preserved tyrosine hydroxylase activity. The findings in the basal ganglia are compatible with manganese toxicity. The vascular pathology is likely a joint effect of infection and the ephedrone toxicity on the vessels. © 2020 International Parkinson and Movement Disorder Society.

Clinical presentation of Y189C mutation of the NOTCH3 gene in the Polish family with CADASIL.

INTRODUCTION: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary, progressive ischemic disease of small vessels of the brain characterized by migraine with aura (MA), recurrent subcortical ischemic episodes, cognitive decline and psychiatric disorders. CADASIL is caused by mutations in the NOTCH3 gene. We identified the NOTCH3 Y189C mutation as a genetic cause of CADASIL in a Polish family and provided its first clinical manifestation. MATERIAL AND METHODS: The study included twelve subjects from one family. The NOTCH3 mutation, APOE and MTHFR polymorphisms were determined by high-resolution melting analyses (HRMA) and Sanger sequencing. Neuroimaging included CT and MRI. Ultrastructural examination of skin-muscle biopsy material of the proband was performed. RESULTS: The NOTCH3 Y189C mutation was present in a 36-year-old woman and her two sisters (aged 40 and 27) from 6 siblings. The MA was found in all of them, and started or became more severe after childbirth. The numerous T2/FLAIR hyperintense lesions were shown in the brain MRI. The deposition of granular osmiophilic material in the wall of small vessels of the proband observed in histopathological analysis confirmed the high degree of CADASIL severity. CONCLUSIONS: Patients with the Y189C mutation of NOTCH3 from the same family display a similar phenotype of CADASIL.

The prevalence and types of oral- and pharyngeal-stage dysphagia in patients with demyelinating diseases based on subjective assessment by the study subjects.

BACKGROUND: Studies show that dysphagia is a common problem in patients with demyelinating diseases. However, there are no published studies on dysphagia in this group of patients, which would include the individual phases or the safety and effectiveness of the swallowing process. OBJECTIVE: The main objective of this study was to assess the prevalence of swallowing disorders and to characterize them based on subjective assessment by the study subjects with multiple sclerosis and Devic's syndrome. METHOD: The study included 72 patients (47 F, 25 M). Patients at risk of dysphagia were identified using the DYMUS, EAT-10 and SDQ questionnaires. To assess the type of oral- and pharyngeal-stage dysphagia, questions in the questionnaires were classified into groups according to symptoms typical of each stage. RESULTS: The risk of dysphagia and the need for instrumental examination were identified in 37.5% of the study subjects. Pharyngeal-stage dysphagia (repeated swallowing, increased effort of swallowing, cough, a feeling of food sticking in the throat) was reported to occur at a significantly higher frequency. However, no differences were found between difficulty in swallowing liquids and difficulty in swallowing solid food. CONCLUSION: There is a need for further research, which should include a detailed dysphagia-oriented diagnosis, with a view to gaining a detailed insight into the pathophysiology of deglutition in this group of patients.

Nuclear abnormalities in vascular myocytes in cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a stroke and dementia syndrome with degeneration and loss of vascular smooth muscle cells (VSMCs). The disease is due to mutations in NOTCH3 playing an important role in VSMC differentiation, proliferation and apoptosis. Searching for a possible cause of VSMC dysfunction in CADASIL, we investigated morphology and proliferative activity the affected myocytes. In material from autopsy brains and skin-muscle biopsies of patients with CADASIL diagnosis, assessment of VSMCs in arterial vessels at the level of light and electron microscopy was performed. Proliferative activity of VSMCs was evaluated in immune reactions to proliferative markers: proliferating cell nuclear antigen, and cyclins B1 and D. In CADASIL, abnormal morphology of VSMC nuclei was observed in 18.1%, 11.5%, and 6.9% of the cerebral, skin, and skeletal muscle vessels, respectively. The affected myocytes showed variability in nuclear size, irregularity in nuclear shape, and abnormal chromatin appearance. Frequently, double nuclei of equal size or micronuclei were observed. Sometimes, even multinuclear myocytes were found. In some of the nuclei immune reactions to the examined proliferative markers were positive. Aberrant structure and number of VSCM nuclei, and their immunoreactivity to proliferative markers suggest mitotic instability of vascular myocytes in CADASIL. We speculate that mutant NOTCH3 which is unable to control properly VSMC proliferation, and may be responsible for their premature or inappropriate entry into mitosis, irreversible arrest of the cell cycle, senescence or degeneration and loss.

Ultrastructural changes in microvessels in familial hemiplegic migraine with CACNA1A mutation.

AIMS: Familial hemiplegic migraine type 1 (FHM1) due to mutations in the CACNA1A gene is known as functional vascular disorder with cerebellar atrophy. We describe a case of a FHM1 family in which pathological changes occurred in both brain neuroimaging and skin and muscle biopsy. MATERIALS AND METHODS: In 5 of 18 affected family members, brain MRI scans revealed hyperintense changes in the cerebral white matter. In 2 of these 5 patients, skin and muscle biopsies were performed at the interictal period of the disease and examined under light and transmission electron microscopy. RESULTS: Ultrastructural examination of the biopsy samples revealed abnormal appearance of microvessels resembling oncosis. In the affected vessels, endothelial cells and myocytes/pericytes showed clear cytoplasm, distended endoplasmic reticulum, enlarged mitochondria, and numerous intracytoplasmic vesicular structures. Swollen endothelial cells often significantly narrowed vessel lumen. CONCLUSION: The morphological changes described for the first time in FHM1 suggest that the disease may not only be a functional, but also a structural vascular disorder. We suggest that the presence of these vascular abnormalities can interfere with microcirculation causing damage to the cerebral white matter, visible in MRI scans as hyperintense changes.
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Cerebral amyloid angiopathy-related inflammation - A case report presenting diagnostic difficulties.

We describe an 86-year-old woman with a history of hypertension who presented sudden disturbances of consciousness and left hemiparesis. Brain magnetic resonance imaging (MRI) revealed diffused hyperintensive changes on T2-weighted images localized subcortically in the white matter of both cerebral hemispheres, corresponding to acute vasogenic edema, causing moderate mass effect. Posterior reversible encephalopathy syndrome was initially diagnosed. After implementation of anti-edema intravenous steroid treatment and hypotensive therapy the symptoms began to retire, till the total regression. The successive hospitalizations took place two and eight months later due to the occurrence of seizures, motor deficits and the development of mild cognitive impairment. Brain MRI revealed progression of the white matter changes and diffused subcortical microhemorrhages. Each time pulse steroid therapy was implemented and the symptoms improved significantly after several days. Chronic oral steroid treatment resulted in the stabilization of neurological status. The long-term observation of clinical symptoms, remission after immunosuppressive therapy and white matter changes with subcortical microhemorrhages in brain MRI leaded to the diagnosis of cerebral amyloid angiopathy-related inflammation.

Sporadic amyotrophic lateral sclerosis: is SMN-Gemins protein complex of importance for the relative resistance of oculomotor nucleus motoneurons to degeneration?

Lower motoneurons (MNs) show varied vulnerability in amyotrophic lateral sclerosis (ALS): those of non-ocular brainstem nuclei and most of those of the spinal cord are highly vulnerable, while those of extraocular brainstem nuclei are quite resistant. Results of our former study on the immunoexpression of the survival of motor neuron protein (SMN) and Gemins 2-4 in cervical spinal cord anterior horn -MNs of sporadic ALS patients suggested that a relative deficit in Gemin2 may play some role in the pathomechanism of the disease. Here, we tested this idea further by comparing immunoexpression patterns of SMN and Gemins 2-8 between MNs of the oculomotor nucleus and -MNs of the cervical spinal cord anterior horns in autopsy material from sALS patients and controls. In the latter, no considerable difference in any studied protein was found between these structures except that SMN expression was slightly but significantly lower (p < 0.01) in the oculomotor MNs. In the sporadic ALS patients, the expression of SMN, Gemin4 and Gemin7 was significantly weaker (p < 0.05, p < 0.05 and p < 0.01, respectively), while that of Gemin8 was stronger (p < 0.001) in the MNs of the oculomotor nucleus than in the examined cervical spinal cord anterior horn -MNs. The immunoexpression of Gemin3 and Gemin6 in the spinal cord correlated strongly negatively with ALS duration (Spearman's correlation coefficient: RS = -0.84, p < 0.001, and RS = -0.86, p = 0.002, respectively). In the oculomotor nucleus MNs, no studied protein immunoexpression correlated significantly with ALS duration, but there was a tendency for such negative correlation for Gemin2 (RS = -0.56, p = 0.07). There was an apparent relative deficit of Gemin2 and Gemin8 in the spinal cord -MNs and of Gemins 2, 4 and 7 in the oculomotor nucleus MNs. These data do not support the hypothesis that the diverse ALS vulnerability of the two MN subsets is related to their disparate expression patterns of SMN and Gemins 2-8. The differences in these patterns may result from ALS-related epiphenomena, or from intrinsic differences in the structure and function between the MN subsets, or both.

Identification of the first in Poland CACNA1A gene mutation in familial hemiplegic migraine. Case report.

INTRODUCTION: Migraine is a common neurological disorder characterized by a particular phenotype, complex pathophysiology and a heterogeneous genetic background. Among several heritable forms, familial hemiplegic migraine is the best described one. In the majority of cases it is caused by mutations in one of three different genes. CASE REPORT: Clinical symptoms of a 47 year old proband (and independently described in his 20 year old son) as well as differential diagnosis are discussed in the presented report. The most characteristic were recurrent attacks of blurred vision, paresthesias and hemiparesis often accompanied by speech disturbances and followed by severe headache with vomiting. Advanced morphological and genetic procedures were required to exclude MELAS, CADASIL and Call-Fleming syndrome. Finally, the definite diagnosis was possible after the application of the whole exome sequencing technique. It confirmed, for the first time in the Polish population, a heterozygous T666M mutation (c.1997C>T; p.Thr666Met) in the CACNA1A gene in the proband, the proband's son and in several other family members. CONCLUSION: The presented report provides clinical and genetic insight into familial hemiplegic migraine 1 resulting from a mutation in the CACNA1A gene.

What factors determine phenotype of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL)? Considerations in the context of a novel pathogenic R110C mutation in the NOTCH3 gene.

We report patients from a Polish family with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) who possess a novel heterozygous R110C mutation in exon 3 of the NOTCH3 gene leading to stereotypical cysteine loss. The proband had only seizure attacks and her magnetic resonance imaging (MRI) showed very numerous hyperintense foci in the cerebral white matter in a location characteristic of CADASIL. Distinctive ultrastructural assessment of vessels from skin-muscle biopsy revealed only mild degenerative changes but relatively numerous homogeneous deposits of granular osmiophilic material (GOM). In the other symptomatic family members with the same mutation ischaemic strokes were present but not epilepsy. In the proband's affected brother at a similar age, the brain MRI was normal but vessels showed pronounced degenerative changes and irregular GOM deposits. The present report not only extends the list of known pathogenic mutations responsible for CADASIL but also emphasizes clinical and morphologic variability among family members with the same NOTCH3 mutation, suggesting that probably additional factors, not only mutations, may influence the disease phenotype..

Disturbed integrin expression in the vascular media in CADASIL.

CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is an inherited angiopathy characterized by degeneration and loss of vascular smooth muscle cells (VSMCs) of still unknown pathomechanism. Many functions of VSMCs, such as adhesion, apoptosis, contraction, differentiation, migration, and proliferation are determined by integrins - surface adhesion receptors involved in binding and interactions between cells and extracellular matrix (ECM). Since integrins play such an important role in VSMCs biology, disturbances in their expression may influence myocytes behavior and fate in CADASIL. In this study, we focused on the most important compounds of VSMCs integrins: subunits α4, ß1, and ß3 in an attempt to elucidate their immune expression in the arterial media of CADASIL patients. The immunohistochemistry revealed a decreased expression of integrin ß1 subunit (p < 0.001) but similar to the control expression of integrin subunits α4 and ß3. Decreased ß1 immunoreactivity was observed in capillary vessels, arterioles, and small arteries. The abnormal immune expression of integrin ß1 subunit was found even in microvessels without microscopically noted degenerative changes, which suggests that this is an early phenomenon in CADASIL. Since integrin ß1 subunit is a compound of 10 heterodimer integrin receptors, its disturbed expression may significantly influence VSMCs biology leading to myocytes degeneration and loss via anoikis - a type of apoptotic cell death due to loss or inappropriate cell adhesion to ECM.

Nanofiber mat spinal cord dressing-released glutamate impairs blood-spinal cord barrier.

An excessive glutamate level can result in excitotoxic damage and death of central nervous system (CNS) cells, and is involved in the pathogenesis of many CNS diseases. It may also be related to a failure of the blood-spinal cord barrier (BSCB). This study was aimed at examining the effects of extended administration of monosodium glutamate on the BSCB and spinal cord cells in adult male Wistar rats. The glutamate was delivered by subarachnoidal application of glutamate-carrying electrospun nanofiber mat dressing at the lumbar enlargement level. Half of the rats with the glutamate-loaded mat application were treated systemically with the histone deacetylase inhibitor valproic acid. A group of intact rats and a rat group with subarachnoidal application of an 'empty' (i.e., carrying no glutamate) nanofiber mat dressing served as controls. All the rats were euthanized three weeks later and lumbar fragments of their spinal cords were harvested for histological, immunohistochemical and ultrastructural studies. The samples from controls revealed normal parenchyma and BSCB morphology, whereas those from rats with the glutamate-loaded nanofiber mat dressing showed many intraparenchymal microhemorrhages of variable sizes. The capillaries in the vicinity of the glutamate-carrying dressing (in the meninges and white matter alike) were edematous and leaky, and their endothelial cells showed degenerative changes: extensive swelling, enhanced vacuo-lization and the presence of vascular intraluminal projections. However, endothelial tight junctions were generally well preserved. Some endothelial cells were dying by necrosis or apoptosis. The adjacent parenchyma showed astrogliosis with astrocytic hypertrophy and swelling of perivascular astrocytic feet. Neurons in the parenchyma revealed multiple symptoms of degeneration, including, inter alia, perikaryal, dendritic and axonal swelling, and destruction of organelles. All the damage symptoms were slightly less severe in the rats given valproic acid treatment, and were absent from both the intact rats and the rats with 'empty' nanofiber mat dressing. These results demonstrate that glutamate-loaded nanofiber mat dressing can locally create glutamate levels capable of damaging BSCB and that the resulting damage can be mitigated with concurrent systemic valproate treatment.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) - literature review apropos an autopsy case.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a non-atherosclerotic, non-amyloid cerebral angiopathy involving small arteries and arterioles. This entity presents vascular changes in the form of smooth muscle degeneration with swollen myocytes and PAS-positive granular deposits, together with vascular fibrosis and hyalinization. In parallel, diffuse white matter destruction with infarcts, tissue rarefaction, spongiosis, lacunes and demyelination are characteristic. Ultrastructurally, vascular granular osmiophilic material (GOM) is pathognomonic for this hereditary disease caused by NOTCH3 mutation. We diagnosed CADASIL in the autopsy examination of a 53-year-old woman with a 9-year history of a progressive neurological disease with complex motor and cognitive deficits, accompanied by non-specific diffuse white matter changes on neuroimaging. Despite several multicentre hospitalizations, the precise diagnosis was not established until the post-mortem examination of the brain was made. CADASIL is a rare entity, but it should be considered by a pathologist in a differential diagnosis of vascular diseases of the brain, especially in cases with atypical clinical presentation and familial history. The prompt diagnosis depends on the quality of the brain autopsy and proper sampling. The post mortem examination, where "Morituri vivos docent", is still significant.

Paraneoplastic brainstem encephalomyelitis and atypical form of chronic inflammatory demyelinating polyneuropathy in patient with testicular germinal tumor-is this an overlap syndrome? a case report.

Paraneoplastic neurologic syndromes are diagnosed when neurologic symptoms are associated with neoplasm and other causative factors are excluded. They may precede or be simultaneous to various types of neoplasms, mainly malignant. In men up to 45-50 years old the most common cancer causing the paraneoplastic syndrome is testicle tumor, manifesting usually as limbic/brain stem encephalitis and myelitis. Usually effective treatment of underlying neoplasm brings resolution of neurologic symptoms. But corticosteroids and intravenuous immunoglobulins are also used. In the presented case a 37-year-old man was primarily diagnosed and treated for progressive tetraparesis with signs of both upper and lower motor neuron dysfunction, associated with bulbar symptoms. Having various diagnostic procedures performed an atypical form of chronic inflammatory demyelinating polyradiculoneuronopathy was primarily suspected, but eventually a discovery of endodermal sinus tumor in the testicle enabled to state the diagnosis of possible paraneoplastic syndrome. In spite of chemotherapy the patient died shortly after the diagnosis because of infectious complications. Histopathology displayed intense inflammatory changes in the brain stem as well as in cranial nerves and cervical spinal cord. The same immunological process evoked by various pathogenetic factors (infection vs. neoplasm) may cause similar clinical picture and hinder the diagnosis. Most importantly it may delay the proper way of treatment.

NF-κB deficit in spinal motoneurons in patients with sporadic amyotrophic lateral sclerosis--a pilot study.

Amyotrophic lateral sclerosis (ALS) is a fatal incurable neurodegenerative disease whose etiology is unknown and pathogenesis is still not fully understood. A great majority of its cases are sporadic. Clinical ALS signs are caused by damage and dying-out of the lower and upper motor neurons. This study was aimed at identifying possible sporadic ALS-associated aberrations in the spinal cord expression of the transcription nuclear factor κ light-chain-enhancer of activated B cells (NF-κB). NF-κB is widely distributed among various cell types, including those specific for the central nervous system (CNS), and is involved in the control of many physiological and pathological processes, including, inter alia, inflammatory response, proliferation, angiogenesis, and cell survival and death. It is constitutively expressed and its inactive form resides in the cytoplasm. After activation, it enters the cell nucleus and promotes the transcription of target genes. NF-κB is a dimer and its most common form is a heterodimer made of subunits p50 and p65. In this study, we estimated and compared by immunohistochemical means the contents of these subunits in spinal cord motoneurons in a few archival cases of sporadic ALS of varying disease duration and the respective age-matched control cases with no CNS pathology. The major goal of the study was to seek possible changes in the expression of these proteins in the course of the disease. The control cases showed a strong expression of both p50 and p65 in spinal cord motoneurons, with both cytoplasmic and nuclear localization. In contrast, the ALS cases studies revealed a considerably lower and varying intensity of specific immunohistochemical staining for the two subunits, which suggested an increased deficit of their expression linked to longer disease duration. Moreover, there was an apparent shift toward mostly cytoplasmic localization of the two subunits. These preliminary data suggest that the changes in the expression of theses NF-κB subunits may be involved in pathogenesis of sporadic ALS.

Diverse expression of selected SMN complex proteins in humans with sporadic amyotrophic lateral sclerosis and in a transgenic rat model of familial form of the disease.

BACKGROUND AND OBJECTIVE: There is circumstantial evidence linking sporadic amyotrophic lateral sclerosis (ALS) cases to a malfunction or deficit of a multimeric SMN complex that scrutinizes cellular RNAs; the core of this complex is survival motor neuron (SMN, or gemin 1) protein. We intended to verify this hypothesis by comparing the expression of both SMN and several other functionally associated gemins in the anterior horn motoneurons of patients who died of sporadic ALS (sALS), of transgenic rats with overexpression of the mutated human superoxide dismutase 1 gene (SOD1(G93A)) that represent a model of familial ALS (fALS), and of the respective controls. METHODS: Using archival material of paraffin blocks with samples of human and rat spinal cords, immunohistochemical reactions with antibodies against SMN and gemins 2, 3, and 4 were performed and assessed by light microscopy. RESULTS: The expression of SMN and all other studied gemins was observed in motoneurons of sALS patients, fALS rats, and in all controls, although the intensity varied. The immunolabeling was most intense in sALS patients with relatively fast disease course, and decreased with increasing disease duration in both the human sALS and rat fALS material. Irrespective of the disease stage, sALS material showed no or very low gemin 2 immunoreactivity, while clear gemin 2 immunoreactivity was observed in all fALS rats and control material. CONCLUSION: The deficient expression of gemin 2 in spinal cord motoneurons in human sALS may lead to a dysfunction and loss of neuroprotective action of the SMN complex.

Non-woven nanofiber mats - a new perspective for experimental studies of the central nervous system?

(Sub)chronic local drug application is clearly superior to systemic administration, but may be associated with substantial obstacles, particularly regarding the applications to highly sensitive central nervous system (CNS) structures that are shielded from the outer environment by the blood-brain barrier. Violation of the integrity of the barrier and CNS tissues by a permanently implanted probe or cannula meant for prolonged administration of drugs into specific CNS structures can be a severe confounding factor because of the resulting inflammatory reactions. In this study, we tested the utility of a novel way for (sub)chronic local delivery of highly active (i.e., used in very low amounts) drugs to the rat spinal cord employing a non-woven nanofiber mat dressing. To this end, we compared the morphology and motoneuron ( + ) counts in spinal cord cervical and lumbar segments between rats with glutamate-loaded nanofiber mats applied to the lumbar enlargement and rats with analogical implants carrying no glutamate. Half of the rats with glutamate-loaded implants were given daily valproate treatment to test its potential for counteracting the detrimental effects of glutamate excess. The mats were prepared in-house by electrospinning of an emulsion made of a solution of the biocompatible and biodegradable poly(L-lactide-co-caprolactone) polymer in a mixture of organic solvents, an aqueous phase with or without monosodium glutamate, and sodium dodecyl sulfate as an emulsifier; the final glutamate content was 1.4 µg/mg of the mat. Three weeks after mat implantation there was no inflammation or considerable damage of the spinal cord motoneuron population in the rats with the subarachnoid dressing of a glutamate-free mat, whereas the spinal cords of the rats with glutamate-loaded nanofiber mats showed clear symptoms of excitotoxic damage and a substantial increase in dying/damaged motoneuron numbers in both segments studied. The rats given systemic valproate treatment showed significantly lower percentages of damaged/dying motoneurons in their lumbar enlargements. These results demonstrate the capacity of nanofiber mats for generation of neurotoxic glutamate in the rat CNS. However, the tested nanofiber mats need further improvements aimed at extending the period of effective drug release and rendering the release more steady.

CADASIL patient with extracellular calcium deposits.

We report the case of a 57-year-old male patient with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) diagnosed on the basis of ultrastructural and genetic examinations. Ultrastructurally, granular osmiophilic material (GOM) deposits, degeneration and loss of vascular smooth muscle cells (VSMC) and pericytes in small arterial and capillary vessels from skin-muscle biopsy typical of CADASIL were visible. Degeneration of pericytes and endothelial cells were often pronounced, which resulted in a complete disappearance of mural cells and extremely severe thickening of the basement membrane. Degenerative changes in blood vessels, especially evident in skeletal muscle arterioles, also included significant vacuolization of VSMC, misshapen nuclei both in vessel wall cells and skeletal muscle fibres, and deposits of a hyaline material and calcium in the vessel wall. Abundant calcium deposits were located in the vascular basement membrane and exhibited laminar morphology with abnormally arranged light and dark bands. In the basement membrane of the most severely affected microvessels, only clusters of calcium deposits and remnants of the mural cells were observed. Laminar calcifications were also observed within the basement membrane surrounding skeletal muscle fibres. Such abundant calcium deposits in CADASIL have not as yet been described. Morphological findings, described in this report, expand the spectrum of histopathological changes in this genetically determined angiopathy.