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.

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.

We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female. All presented with panhypopituitarism. Two also had visual field defect. On neuroimaging all tumors showed suprasellar extension and were indistinguishable from pituitary adenoma. None showed imaging or operative evidence of dural involvement. All were gross totally removed: four by transsphenoidal surgery and one by frontal craniotomy. Follow-up ranged from 2 to 68 months (mean 35.4 months). No recurrences were noted. The clinical workup was noncontributory in all but two patients: one (case no. 4) with an oncocytic thyroid adenoma and another (case no. 5) with squamous carcinoma of both the uterine cervix and of vocal cord. Histologically, the five tumors were composed mainly of fascicles of spindle cells with eosinophilic, granular cytoplasm. Mitoses were rare and necrosis was absent. Neoplastic cells were immunoreactive for vimentin, epithelial membrane antigen, S-100 protein, and galectin-3. Stains for pituitary hormones, synaptophysin, chromogranin, glial fibrillary acidic protein, cytokeratin CAM5.2, smooth muscle actin, CD34, and CD68 were negative. No thyroglobulin immunoreactivity was noted in the tumor of case no. 4. Ultrastructurally, the neoplastic cells contained numerous mitochondria with lamellar cristae. The neoplastic cells were linked by intermediate junctions and desmosomes. No secretory granules were noted. The histologic, immunohistochemical, and fine structural features of these tumors were unlike those of pituitary adenoma or any other primary sellar tumor. A derivation from adenohypophyseal folliculostellate cells is suggested.

Summary: 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 µm. 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 µm 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.

Clinical and electrophysiological signs of peripheral neuropathy were found in 10 of 46 patients (21.7%) with primary Sjögren's syndrome, symmetric polyneuropathy in seven (mainly sensory in five, mainly autonomic in two), sensory neuronopathy in two patients, and mononeuropathy multiplex in one patient. Peripheral neuropathy was the presenting manifestation in five patients (10.9%). Onset of the disease after 50 years was significantly more common in the polyneuropathy group (six of seven) than in non-neuropathic patients with primary Sjögren's syndrome (14 of 36; p = 0.034). No other difference in clinical or laboratory variables between neuropathic and non-neuropathic patients with primary Sjogren's syndrome was found. Neurophysiological study showed variable findings predominantly suggesting an axonopathy. Nerve biopsy showed moderate remyelination and regeneration in four patients, and fibre loss, mainly of large size, in three. Necrotising vasculitis was not seen but alterations of the endoneurial microvessels were prominent.