Review: Danon disease: Review of natural history and recent advances.

Danon disease is a severe multisystem disorder clinically characterized by hypertrophic cardiomyopathy, skeletal myopathy and mental retardation in male patients, and by a milder phenotype (predominantly involving cardiac muscle) in female patients. The disease is inherited as an X-linked dominant trait. The primary deficiency of lysosome-associated membrane protein-2 (LAMP-2) causes disruption of autophagy, leading to an impaired fusion of lysosomes to autophagosomes and biogenesis of lysosomes. We surveyed over 500 Danon disease patients reported in the literature from the first description to the present, in order to summarize the clinical, pathological and molecular data and treatment perspectives. An early molecular diagnosis is of crucial importance for genetic counselling and for therapeutic interventions: in male patients, the prognosis is poor due to rapid progression towards heart failure, and only heart transplantation modifies the disease course.

Subpopulations of dermal skin fibroblasts secrete distinct extracellular matrix: implications for using skin substitutes in the clinic.

BACKGROUND: While several commercial dermoepidermal scaffolds can promote wound healing of the skin, the achievement of complete skin regeneration still represents a major challenge. OBJECTIVES: To perform biological characterization of self-assembled extracellular matrices (ECMs) from three different subpopulations of fibroblasts found in human skin: papillary fibroblasts (Pfi), reticular fibroblasts (Rfi) and dermal papilla fibroblasts (DPfi). METHODS: Fibroblast subpopulations were cultured with ascorbic acid to promote cell-assembled matrix production for 10 days. Subsequently, cells were removed and the remaining matrices characterized. Additionally, in another experiment, keratinocytes were seeded on the top of cell-depleted ECMs to generate epidermal-only skin constructs. RESULTS: We found that the ECM self-assembled by Pfi exhibited randomly oriented fibres associated with the highest interfibrillar space, reflecting ECM characteristics that are physiologically present within the papillary dermis. Mass spectrometry followed by validation with immunofluorescence analysis showed that thrombospondin 1 is preferentially expressed within the DPfi-derived matrix. Moreover, we observed that epidermal constructs grown on DPfi or Pfi matrices exhibited normal basement membrane formation, whereas Rfi matrices were unable to support membrane formation. CONCLUSIONS: We argue that inspiration can be taken from these different ECMs, to improve the design of therapeutic biomaterials in skin engineering applications.

Juvenile dermatomyositis: A report of three cases.

Juvenile dermatomyositis (JDM), an autoimmune idiopathic myositis, is characterized by rash and proximal muscle weakness. Immunohistopathology typically shows perivascular inflammatory infiltrate with predominance of CD4+ T lymphocytes, perifascicular atrophy, and upregulation of major histocompatibility complex class I. JDM has been attributed to a humoral-driven muscle microangiopathy probably implicating the type I interferon pathway. Tubulo-reticular inclusions present in endothelial cell of muscle are biomarkers of interferon exposure, and so may be an indirect data of this myopathy especially in the absence of rash and inflammatory infiltrate. We report on three patients in which electron microscopy solves the differential diagnosis among infantile myositis showing peculiar inclusions.

Myocardial adenomatoid tumor in eight cattle: evidence for mesothelial origin of bovine myocardial epithelial inclusions.

The adenomatoid tumor is an uncommon benign lesion, thus far described only in humans. Adenomatoid tumors typically arise in the genital tract, exceptionally in the heart, and usually represent an incidental finding. Microscopically, they are constituted by epithelioid cells that form tubular structures and anastomosing channels within a fibrous stroma. Mesothelial origin of these lesions is suggested by their immunohistochemical characteristics. In cattle, previously reported myocardial epithelial inclusions are morphologically similar in that the cells are immunoreactive for both cytokeratins and vimentin, and bear surface microvilli. Myocardial lesions found incidentally at slaughter in 8 cattle histologically resembled the so-called bovine myocardial epithelial inclusions and had morphologic and immunohistochemical features consistent with human adenomatoid tumor. All lesions were in the left ventricular myocardium, adjacent to the epicardium, and composed of epithelioid cells that formed cords and tubules, and were immunoreactive for pan-cytokeratins, cytokeratin 5/6, vimentin, calretinin, Wilms' tumor 1 suppressor gene, and CD30 antigen. By electron microscopy, numerous long slender microvilli were associated with desmosomes and tonofibrils. The immunohistochemical and ultrastructural features were considered consistent with mesothelial origin. These lesions, corresponding to the previously described myocardial epithelial inclusions in cattle, might be considered embryologic rests and could represent the bovine counterpart of the human adenomatoid tumor.

Cerebral Mitochondrial Microangiopathy Leads to Leukoencephalopathy in Mitochondrial Neurogastrointestinal Encephalopathy.

BACKGROUND AND PURPOSE: Mitochondrial neurogastrointestinal encephalopathy is a rare disorder due to recessive mutations in the thymidine phosphorylase gene, encoding thymidine phosphorylase protein required for mitochondrial DNA replication. Clinical manifestations include gastrointestinal dysmotility and diffuse asymptomatic leukoencephalopathy. This study aimed to elucidate the mechanisms underlying brain leukoencephalopathy in patients with mitochondrial neurogastrointestinal encephalopathy by correlating multimodal neuroradiologic features to postmortem pathology. MATERIALS AND METHODS: Seven patients underwent brain MR imaging, including single-voxel proton MR spectroscopy and diffusion imaging. Absolute concentrations of metabolites calculated by acquiring unsuppressed water spectra at multiple TEs, along with diffusion metrics based on the tensor model, were compared with those of healthy controls using unpaired t tests in multiple white matters regions. Brain postmortem histologic, immunohistochemical, and molecular analyses were performed in 1 patient. RESULTS: All patients showed bilateral and nearly symmetric cerebral white matter hyperintensities on T2-weighted images, extending to the cerebellar white matter and brain stem in 4. White matter, N-acetylaspartate, creatine, and choline concentrations were significantly reduced compared with those in controls, with a prominent increase in the radial water diffusivity component. At postmortem examination, severe fibrosis of brain vessel smooth muscle was evident, along with mitochondrial DNA replication depletion in brain and vascular smooth-muscle and endothelial cells, without neuronal loss, myelin damage, or gliosis. Prominent periependymal cytochrome C oxidase deficiency was also observed. CONCLUSIONS: Vascular functional and histologic alterations account for leukoencephalopathy in mitochondrial neurogastrointestinal encephalopathy. Thymidine toxicity and mitochondrial DNA replication depletion may induce microangiopathy and blood-brain-barrier dysfunction, leading to increased water content in the white matter. Periependymal cytochrome C oxidase deficiency could explain prominent periventricular impairment.

Endoscopic appearance of GERD: putative role of cell proliferation.

BACKGROUND: Erosive esophagitis is a frequent endoscopic feature in patients with gastro-oesophageal reflux disease. However, most of patients with heartburn/regurgitation have a non-erosive reflux disease. The reason for this heterogeneous impact of gastro-oesophageal reflux disease on oesophageal mucosa is unknown to date. AIM: To evaluate the cell proliferation status of oesophageal epithelium in both healthy normal subjects and patients with gastro-oesophageal reflux disease with or without erosions. MATERIALS AND METHODS: All the subjects underwent endoscopy and biopsies were taken at 5 cm from the squamo-columnar junction. Specimens were analysed both at histology and at transmission electron microscopy. Cell proliferation was evaluated by MIB1 immunostaining. Of the 85 subjects were studied, 10 were healthy controls with normal pH-testing and macroscopical, histological and ultrastructural patterns; 37 were patients with erosive esophagitis, and 38 patients with non-erosive reflux disease. RESULTS: At histology, of the 37 patients affected by erosive esophagitis, 30 had normal mucosa and 7 showed mild oesophagitis. One patient with non-erosive reflux disease showed signs of oesophagitis at histology. At TEM, all patients with gastro-oesophageal reflux disease had ultrastructural patterns of damage i.e. dilations of intercellular spaces (DIS), and all controls had a normal ultrastructural pattern. The mean (+/-SD) MIB1-LI values of normal subjects and non-erosive reflux disease and erosive oesophagitis patients were 62.2% (+/-9.1), 29.7% (+/-7.2) and 16.2% (+/-5.2), respectively; there were significant differences among the three groups (p<0.001). CONCLUSIONS: Oesophageal mucosa of patients with reflux symptoms presents a decrease in MIB1 immunostaining of 50% and 25% in non-erosive reflux disease and erosive esophagitis patients with respect to normal subjects.

Building blocks of the GIPU, Italian Group of Ultrastructural Pathology.

The Italian Group of Ultrastructural Pathology, GIPU, is a scientific organization committed to promote the art and science of Electron Microscopy (EM) in the pathology field in Italy, sharing its professional work with a public audience. The history of the GIPU goes back to 1990s when a founder group set up the Italian Group of Ultrastructural Diagnostic (GIDU) in Milan. The central focus of annual meetings was on EM, transmission and scanning one, about interesting cases in which it was instrumental in diagnosis. In the 1990s, ultrastructure was still the gold standard for cell/tissue morphology, biology, biochemistry, diagnostic pathology, and played an important role in tailored medicine. So, especially transmission EM, could play a critical role in the diagnosis of various diseases as in human as in animals. Best topics of the annual scientific meetings of the group were kidney, muscle, heart, and liver pathology, infertility, neuropathology, respiratory diseases, skin diseases, storage diseases, tumor pathology, infectious diseases, parasitology, veterinary pathology and more. Nowadays, EM is a method whose importance for diagnosis and pathology is well established: it is still essential in several pathologies, helpful in others, and welcome implemented in eclectic research pathology. Omission of EM likely makes the studies suboptimal and wasteful. So, from 2007 the name of the group has been changed to the Italian Group of Ultrastructural Pathology (GIPU) to favor broader applications of EM also to pathology research field. During last decades, GIDU/GIPU has interconnected with international (Society for Ultrastructural Pathology) and european (European Society of Pathology and Joint Meeting with the European Electron Microscopy Working Group) scientific society, according its statute. By 1991, GIPU has had 40 members: membership in this Group is still open and welcome to all pathologists, PhD, electron microscopy technologists, pathology trainees, and researchers interested in pathology and electron microscopy.

Ultrastructural changes in dysferlinopathy support defective membrane repair mechanism.

BACKGROUND: The dysferlin gene has recently been shown to be involved in limb girdle muscular dystrophy type 2B and its allelic disease, Miyoshi myopathy, both of which are characterised by an active muscle degeneration and regeneration process. Dysferlin is known to play an essential role in skeletal muscle fibre repair, but the process underlying the pathogenetic mechanism of dysferlinopathy is not completely understood. AIMS: To define both specific alterations of muscle fibres and a possible sequential mechanism of myopathy development. METHODS: A histological, immunohistochemical, and ultrastructural analysis of 10 muscle biopsies from patients with molecularly diagnosed dysferlinopathy. RESULTS: An inflammatory response was seen in most of the muscle biopsies. The immunohistochemical pattern demonstrated active regeneration and inflammation. Non-necrotic fibres showed alterations at different submicroscopic levels, namely: the sarcolemma and basal lamina, subsarcolemmal region, and sarcoplasmic compartment. In the subsarcolemmal region there were prominent aggregations of small vesicles, probably derived from the Golgi apparatus, which consisted of empty, swollen cisternae. In the sarcolemma there were many gaps and microvilli-like projections, whereas the basal lamina was multilayered. CONCLUSIONS: The histopathological, immunohistochemical, and ultrastructural data show that dysferlinopathy is characterised by a very active inflammatory/degenerative process, possibly associated with an inefficient repair and regenerative system. The presence of many crowded vesicles just beneath the sarcolemma provides submicroscopical proof of a defective resealing mechanism, which fails to repair the sarcolemma.

Chordoid glioma of the third ventricle: an ultrastructural study of three cases with a histogenetic hypothesis.

Chordoid glioma is a rare neoplasm occurring in the third ventricle and, as the name implies, having a chordoid appearance. It is currently considered a glial neoplasm of uncertain histogenesis with distinct clinicopathologic features. We report three cases of chordoid glioma with a focus on the ultrastructural appearance. The patients were two men and one woman aged, respectively, 34, 40, and 43 years. Immunohistochemically, all tumors showed strong and diffuse reactivity for glial fibrillary acidic protein and vimentin, whereas immunoreactivity for epithelial membrane antigen and cytokeratin was focal. Ultrastructurally, they showed features of ependymal differentiation for the presence of an apical pole with microvilli and a basal pole characterized, as in normal ependyma, by many hemidesmosomelike structures connecting cell membranes to the underlying basal lamina. Constant features were a submicroscopic cell body zonation (i.e., perinuclear, intermediate, subapical, and apical regions) and the presence of secretory granules. These findings were similar to those described for the secretory ependymal cells of the subcommissural organ, a small structure located in a dorsocaudal region of the third ventricle that undergoes regression after birth in humans. Our observations suggest that chordoid glioma may represent a subtype of ependymoma whose cells resemble the highly specialized ependyma of the subcommissural organ.

Medullocytoma (lipidized medulloblastoma). A cerebellar neoplasm of adults with favorable prognosis.

This study describes three cases of neuroectodermal cerebellar neoplasms occurring in adults, characterized by a monomorphic population of round cells with scanty cytoplasm and focal areas of lipid accumulation. Astrocytic and neuronal differentiation was confirmed in these cells by glial fibrillary acidic protein and synaptophysin immunoreactivity. Electron microscopy performed in two cases showed neuritic processes, synapses, and dense-core granules. Patients included two men and one woman, and the age at diagnosis was 36, 37, and 57 years, respectively. Two patients refused any postoperative treatment. One of these had two surgically removed recurrences after 10 and 11 years and died postoperatively from intracranial hemorrhage. The second had two recurrences after 10 and 15 years and is alive and in good health at the last follow-up. The third patient received postoperative radiotherapy and is alive and well after 2 years. Review of the literature revealed seven cases of cerebellar neoplasms with histological features similar to those observed in our series. These lesions have been considered a variant of medulloblastomas. The age of patients ranged from 42 to 77 years (mean age, 51 years); four were women, 3 men. Follow-up information available in two cases indicates a 5-year survival with surgery alone. These data indicate that these cerebellar neuroectodermal neoplasms have morphologically unique features and indolent biologic behavior that distinguish them from the highly aggressive medulloblastoma; the term medullocytoma for this form is suggested.

Extraventricular neoplasms with neurocytoma features. A clinicopathological study of 11 cases.

The clinicopathological features of a series of neuronal and mixed neuronal and astrocytic neoplasms of the CNS are described. Patients were aged 5 to 63 years. Six cases were composed predominantly of small round cells with clear cytoplasm resembling central neurocytoma but lacked the characteristic intraventricular location of that tumor. The remaining five cases had similar neurocytomatous features associated with a benign astrocytic component. Ganglion cells and hyalinization vessels were observed in both groups. The growth fraction evaluated with monoclonal antibody Ki67Mib1 was low, ranging from 1 to 1.5%. Immunohistochemical detection of synaptophysin played a crucial role in identifying the neuronal nature of these neoplasms and was instrumental in distinguishing them from oligodendrogliomas, with which they are readily confused. The neuronal nature of the oligodendroglial-like cells was confirmed ultrastructurally in one case. The present cases, together with others reported previously, suggest that neoplasms of the CNS with "neurocytic" components are more frequent than generally assumed and expand the morphologic spectrum of neuronal and mixed neuronal-glial tumors. Except for one patient who died postoperatively, all patients were alive at follow-up ranging from 6 to 80 months.

Lipomatous meningioma: a clinicopathologic study of 18 cases with special reference to the issue of metaplasia.

We report 18 cases of lipomatous meningioma occurring in patients aged 14 to 79, most being females (72%). Sixteen were supratentorial and 2 involved the spinal meninges. Follow-up ranged from 1 to 120 months. Fifteen patients were cured with surgery alone and 3 (17%) experienced a recurrence at 7, 8 and 24 months. Of these, one died with disease 4 years after resection of the primary lesion. Histologically, 12 tumors were meningothelial, 3 transitional, 2 showed myxoid stromal changes and 1 was microcystic. The 2 spinal tumors were atypical. The proportion of fatty cells ranged from 10 to 90%. These resembled mature adipocytes or less commonly lipoblasts. Xanthomatous meningothelial cells were also noted in 6 tumors (30%). Both conventional meningothelial as well as lipid-laden cells exhibited epithelial membrane antigen immunoreactivity. In addition, occasional cells resembling mature adipocytes showed reactivity for S-100 protein. Ultrastructurally, lipidization of neoplastic cells varied from intracytoplasmic lipid droplets to a single massive globule. Moreover, lipid-laden meningothelial cells featured interdigitating cell membranes and well-formed desmosomes. Lipid droplets were not membrane-bound. In that metaplasia denotes differentiation of one mature cell type to another, lipid accumulation in meningiomas cannot be considered true metaplasia since their lipid-laden cells retain the immunophenotype and ultrastructural features of meningothelium. We suggest that this distinctive subset of meningiomas be termed "lipidized meningiomas" rather than being included in the metaplastic category.

A new acrylic resin formulation: a useful tool for histological, ultrastructural, and immunocytochemical investigations.

We describe a new formulation for a hydrophilic resin, mostly composed of glycol methacrylate and hydroxypropyl methacrylate and here referred to as bioacryl, that allows the performance of morphological and immunohistochemical investigations at both light and electron microscopic levels. Immunolocalizations performed on bioacryl-embedded tissues are characterized by high specificity with virtually absent background staining. Finally, the new resin yields satisfactory fine-structural preservation, resulting in ultrastructural images of better quality than those obtained with Lowicryl K4M.

Human cytomegalovirus structural components: intracellular and intraviral localization of p38.

Rabbit antisera raised against the product of ORF UL 80 of human cytomegalovirus (CMV) genome (HindIII L fragment of AD169 strain) as well as IgM from acutely infected patients recognize an antigen of Mr 38 kDa. In the viral particle this antigen is bound via S-S bridge to a lower Mr compound to form a final complex of 62 kDa that is also recognized by rabbit antisera as well as patients' IgM. P38 is present both in the nucleus and in the cytoplasm of CMV-infected cells starting from 24 h p.i. and increasingly thereafter. Immunoelectron microscopy revealed that this antigen is mainly associated with the internal portion of viral capsids both in the nucleus and in the cytoplasm.

Dilated intercellular spaces as a marker of oesophageal damage: comparative results in gastro-oesophageal reflux disease with or without bile reflux.

BACKGROUND: The dilation of oesophageal intercellular spaces, clearly apparent in transmission electron microscopy images, is a marker of cellular damage induced by acid. AIM: To analyse the presence of dilated intercellular spaces and to quantify the scores in controls and in patients with gastro-oesophageal reflux disease or duodenal gastro-oesophageal reflux accompanied by erosive or non-erosive reflux disease. METHODS: Thirty-eight symptomatic patients with gastro-oesophageal reflux disease or duodenal gastro-oesophageal reflux and 12 asymptomatic controls, classified on the basis of pH-metry and bilimetry, underwent endoscopy. Six tissue biopsies were taken from the normal mucosa for light microscopy and transmission electron microscopy evaluation. Dilated intercellular spaces were measured on photomicrographs of the specimens (at least 100 transects were measured for each patient). RESULTS: Twenty-two patients with gastro-oesophageal reflux disease had normal macroscopic mucosa but, at histology, five patients with erosive gastro-oesophageal reflux disease had mild oesophagitis and one had moderate oesophagitis. Seven patients with duodenal gastro-oesophageal reflux had normal mucosa, whilst three with erosive duodenal gastro-oesophageal reflux had mild oesophagitis at histology. At transmission electron microscopy, all controls had dilated intercellular spaces of less than 1.69 microm. Each symptomatic patient had a mean dilated intercellular space value and a mean value of the maximum dilated intercellular space at least three or more times greater than that in controls (P < 0.001). No statistical differences were observed between erosive and non-erosive oesophagitis. CONCLUSIONS: The dilated intercellular space is an extremely sensitive marker of damage in gastro-oesophageal reflux disease, duodenal gastro-oesophageal reflux and non-erosive reflux disease, and serves as the most appropriate marker of damage evaluation in non-erosive reflux disease reported to date. A mean dilated intercellular space of 0.74 micro m provides a cut-off score for damage. No quantitative or qualitative differences in dilated intercellular space scores were found between pure and mixed acid reflux.

Cell proliferation and ultrastructural changes of the duodenal mucosa of patients affected by familial adenomatous polyposis.

Patients affected by familial adenomatous polyposis (FAP) are at risk of developing duodenal neoplasia. Our objective was to detect early abnormalities of the epithelial cell proliferation and ultrastructure of apparently normal duodenal mucosa of FAP patients. Biopsy specimens were taken from the duodenal mucosa. Cell proliferation was studied by immunohistochemistry with proliferating cell nuclear antigen (PCNA), and ultrastructure, by transmission electron microscopy. We found that the PCNA labeling index for duodenal mucosa of patients with FAP was higher in comparison to the case of hospital controls without cancer risk (P = 0.019). Moreover, ultrastructural changes related to an impairment of cell adhesion function were found in all biopsies of FAP patients but not in the duodenal mucosa of the controls. We conclude that alterations of cell proliferation kinetics and epithelial adherens junction structures were phenotypic characteristics of histologically normal duodenal mucosa of FAP patients. These abnormalities may be considered as intermediate biomarkers of neoplasia and potential surrogate endpoints in chemoprevention studies.

Nonrandom gain of chromosome 7 in central neurocytoma: a chromosomal analysis and fluorescence in situ hybridization study.

Central neurocytoma is a benign, slow-growing neoplasm with favourable prognosis. Biomolecular analysis has failed to demonstrate significant alterations, and no cytogenetic alterations have been reported. In this study we demonstrate chromosome 7 gain in three of nine neurocytomas (33%). Traditional cytogenetic analysis performed in four of the nine cases identified trisomy 7 as the sole chromosomal abnormality in one case. Interphase cytogenetics utilizing fluorescent in situ hybridization (FISH) on cell suspensions from formalin-fixed paraffin-embedded tumour tissue performed in all nine cases detected trisomy 7 in two more cases and tetrasomy in another. Our results suggest that chromosome 7 gain is a feature of neuroectodermal tumorigenesis, possibly conferring growth advantage on the neoplastic cells. FISH on interphase nuclei is a valuable adjunct in the genetic evaluation of rare central nervous system neoplasms with low baseline proliferative activity.

Progression on metastatic neuroendocrine carcinoma from a recurrent prolactinoma: a case report.

A 54 year old man was referred to the department of neurosurgery for frontal headache and vomiting. The patient was known in the department because of previous multiple surgery for a locally invasive pituitary prolactinoma (eight years, three years, and one year previously). The neurological examination revealed a frontal mass, which adhered to the dura, suggesting a meningioma. One year later, a left temporal metastasis was removed. Three months later, the patient died, with spinal metastases, of massive lung embolism. Histology revealed a progression of adenohypophyseal prolactinoma on neuroendocrine carcinoma, with an increase in proliferating indexes and modification of hormone production. This study documents a 10 year history of a rare prolactin producing pituitary carcinoma, which metastasised via liquoral flow.

Meningeal sarcoma with rhabdomyoblastic differentiation: case report.

A case of primary neoplasm of the meninges with unusual histological and clinical features, which occurred in a 61-year-old man is described. Although conventional light microscopy revealed an undifferentiated tumor consisting of small- to medium-sized elements, it did not allow any definitive histogenetic interpretation. Immunohistochemistry showed that the neoplastic cells were positive for actin, desmin, myoglobin, and vimentin, thus leading to the diagnosis of meningeal sarcoma with rhabdomyoblastic differentiation. This interpretation was also supported by electron microscopy, in dewaxed tissue samples, which revealed the presence of abortive Z-lines. It is noteworthy that retrospective microscopic examination of all the slides obtained both at initial presentation and at relapses demonstrated in some fields that the undifferentiated population was associated with typical meningiomatous features, as was also shown by the staining for the epithelial membrane antigen. Clinically, the tumor was characterized by an exceedingly long course (10 years). The histogenesis of the tumor and the diagnostic relevance of immunohistochemical techniques are discussed.

Microvascular changes in progressive systemic sclerosis: immunohistochemical and ultrastructural study.

Fifteen patients affected by Progressive Systemic Sclerosis have been studied. With immunofluorescence, specific antibodies against collagen type IV and laminin clearly outlined the microvessels, while endothelial cells showed a brilliant heavy fluorescence for vimentin antibodies. In the deep dermis, fibronectin proved to have increased. At electron microscopy, microvessels appeared with occluded lumina due to the presence of swollen endothelial cells. Endothelial cytoplasm was filled with intermediate filaments (vimentin type), generally condensed into peripherally located bundles or in perinuclear rings. The perivascular basal lamina was thickened and laminated. Although these changes do not demonstrate a specific pattern, representing a common step in several connective tissue disorders, the data tend to confirm a clear involvement of the microvasculature in Progressive Systemic Sclerosis.