Myxofibrosarcoma: Another mimicker of meningioma.

Primary intracranial malignant fibrous histiocytoma (MFH), or myxofibrosarcoma, is an extremely rare condition, with only a few cases reported in the literature. We report a case of a dural-based myxofibrosarcoma in a previously healthy 42-year-old man that was initially presumed to be an atypical meningioma. The findings based on conventional and advanced magnetic resonance sequences, including diffusion-weighted imaging, perfusion weighted imaging and proton magnetic resonance spectroscopy, as well as histopathological aspects, are discussed.

Peritoneal metastasis of a brainstem anaplastic ganglioglioma in a 2-year-old boy: case report and literature review.

Anaplastic gangliogliomas (AGG) are rare tumors of the central nervous system (CNS) that commonly affect children and young adults, with an unusual infratentorial presentation, which is related to hydrocephalus and a worse prognosis. We report a case of a brainstem AGG in a 2-year-old boy who underwent a ventriculoperitoneal shunting (VPS) and later presented peritoneal metastasis. We also reviewed the related literature. Even though rare, disease dissemination through VPS should be sought in patients with CNS tumors and VPS who develop new abdominal symptoms. The early diagnosis and intervention may minimize morbidity and improve quality of life of such patients.

Myxofibrosarcoma: Another mimicker of meningioma.

Primary intracranial malignant fibrous histiocytoma (MFH), or myxofibrosarcoma, is an extremely rare condition, with only a few cases reported in the literature. We report a case of a dural-based myxofibrosarcoma in a previously healthy 42-year-old man that was initially presumed to be an atypical meningioma. The findings based on conventional and advanced magnetic resonance sequences, including diffusion-weighted imaging, perfusion weighted imaging and proton magnetic resonance spectroscopy, as well as histopathological aspects, are discussed.

Vertebral body chondrosarcoma with metastasis to the scalp.

We present a case of a 30-year-old man who had a 3-year history of low back pain. MRI demonstrated an infiltrative mass, affecting the vertebral body and pedicles of L4, with some extension to the vertebral canal. There was also tumor invasion in the inferior vena cava and in the left iliopsoas muscle. The anatomopathological examination of the resected L4 vertebral body was of a malignant neoplasia compatible with mesenchymal chondrosarcoma (high histological grade). About 2 months after surgery, he developed a progressive bladder incontinence, bilateral leg weakness and severe back pain. A new MRI was obtained, confirming progression of the disease. An occipital scalp lesion was detected and biopsy confirmed cutaneous metastasis. Primary malignant bone tumors are rare but should be ruled out in young patients with persistent low back pain. We present a case of a confirmed mesenchymal chondrosarcoma affecting lumbar spine, with MRI and pathological illustrations. Early diagnosis may improve the chances of local disease control and even cure.

ATP Synthase Subunit Beta Immunostaining is Reduced in the Sclerotic Hippocampus of Epilepsy Patients.

Epilepsy is a common disease presenting with recurrent seizures. Hippocampal sclerosis (HS) is the commonest histopathological alteration in patients with temporal lobe epilepsy (TLE) undergoing surgery. HS physiopathogenesis is debatable. We have recently studied, by using mass spectrometry-based proteomics, an experimental model of TLE induced by electrical stimulation. Specifically, protein expressions of both the beta subunit of mitochondrial ATP synthase (ATP5B) and of membrane ATPases were found to be reduced. Here, we investigated tissue distribution of ATP5B and sodium/potassium-transporting ATPase subunit alpha-3 (NKAα3), a protein associated with neuromuscular excitability disorders, in human hippocampi resected "en bloc" for HS treatment (n = 15). We used immunohistochemistry and the stained area was digitally evaluated (increase in binary contrast of microscopic fields) in the hippocampal sectors (CA1-CA4) and dentate gyrus. All HS samples were classified as Type 1, according to the International League Against Epilepsy (ILAE) 2013 Classification (predominant cell loss in CA1 and CA4). ATP5B was significantly decreased in all sectors and dentate gyrus of HS patients compared with individuals submitted to necropsy and without history of neurological alterations (n = 10). NKAα3 expression showed no difference. Moreover, we identified a negative correlation between frequency of pre-operative seizures and number of neurons in CA1. In conclusion, our data showed similarity between changes in protein expression in a model of TLE and individuals with HS. ATP5B reduction would be at least in part due to neuronal loss. Future investigations on ATP5B activity could provide insights into the process of such cell loss.

Idiopathic hypertrophic pachymeningitis as a rare cause of cervical compressive myelopathy.

The spinal form of idiopathic hypertrophic pachymeningitis (IHP) is a rare condition characterized by a chronic progressive diffuse inflammatory fibrosis of the dura mater, which may evolve to the compression of the spinal cord. We present a case report about IHP focusing on its features in magnetic resonance imaging, which are determined by an intradural extramedullary mass in the cervical spine showing hypointensity on T2-weighted images and peripheral enhancement, causing compression of the spinal cord. Histological analysis showed a nonspecific chronic inflammatory process in dense fibrous tissue. The patient had a good outcome after therapy with steroids.

Are human peripheral nerves sensitive to X-ray imaging?

Diagnostic imaging techniques play an important role in assessing the exact location, cause, and extent of a nerve lesion, thus allowing clinicians to diagnose and manage more effectively a variety of pathological conditions, such as entrapment syndromes, traumatic injuries, and space-occupying lesions. Ultrasound and nuclear magnetic resonance imaging are becoming useful methods for this purpose, but they still lack spatial resolution. In this regard, recent phase contrast x-ray imaging experiments of peripheral nerve allowed the visualization of each nerve fiber surrounded by its myelin sheath as clearly as optical microscopy. In the present study, we attempted to produce high-resolution x-ray phase contrast images of a human sciatic nerve by using synchrotron radiation propagation-based imaging. The images showed high contrast and high spatial resolution, allowing clear identification of each fascicle structure and surrounding connective tissue. The outstanding result is the detection of such structures by phase contrast x-ray tomography of a thick human sciatic nerve section. This may further enable the identification of diverse pathological patterns, such as Wallerian degeneration, hypertrophic neuropathy, inflammatory infiltration, leprosy neuropathy and amyloid deposits. To the best of our knowledge, this is the first successful phase contrast x-ray imaging experiment of a human peripheral nerve sample. Our long-term goal is to develop peripheral nerve imaging methods that could supersede biopsy procedures.

Use of p63 and CD10 in the differential diagnosis of papillary neoplasms of the breast.

Papillary neoplasms of the breast represent a complex spectrum ranging from benign to malignant lesions. The myoepithelial cell (MEC) layer is generally continuous in papillomas and increasingly discontinuous to absent in atypical and malignant counterparts. Identification of MECs can be difficult on morphological grounds and currently relies on immunomarkers. We investigated the potential role of p63 and CD10 in 20 papillary lesions and compared them with 1A4 and calponin. In 18 cases, adjacent normal breast tissue was available for study. All four markers were diffusely positive in all samples of normal tissue and benign papillomas indicating similar sensitivity in the identification of MECs. Intense positivity was found in 100% of the cases with 1A4 and CD10, but in only 76% with calponin and in 60.5% with p63 (differences statistically significant, p < 0.05), suggesting that the former two render more reproducible results. The most specific markers were p63 and CD10 which showed cross-reactivity in 0% and in up to 33% of the cases respectively. 1A4 and calponin showed diffuse cross-reactivity in all cases. When assessing benign versus atypical papillomas, the best parameters were diffuse positivity using CD10 or p63, and continuous MEC layer, mainly using CD10. When comparing benign papillomas to carcinomas all parameters were equally useful with 1A4 and CD10. Regardless of the marker, intense positivity was the only parameter that could distinguish atypical papillomas from papillary carcinomas. p63 staining, which renders a nuclear and mostly discontinuous reactivity, was not as useful as the other markers when the parameter continuous MEC layer was evaluated. Although CD10 seems to combine the highest specificity and reproducibility with a good sensitivity, reproducibility of 1A4 is higher. Thus, a minimum panel to assess papillary lesions should include both markers. Although p63 is the most specific, its nuclear and discontinuous pattern may lead to erroneous diagnosis, especially in the differentiation between benign papillomas and atypical/malignant lesions.

p63 and CD10: reliable markers in discriminating benign sclerosing lesions from tubular carcinoma of the breast?

The immunohistochemical detection of myoepithelial cells in benign sclerosing lesions of the breast is useful in distinguishing them from tubular carcinoma. So far, this detection has been carried out using antibodies against cytoskeletal proteins, such as alpha-smooth muscle actin (1A4) and calponin. However, the specificity of these markers has been questioned since they may be expressed in stromal myofibroblasts and vascular smooth muscle. Recently, two novel myoepithelial markers have been described: the nuclear protein p63, a member of the p53 family, and the surface antigen CD10, also known as common acute lymphoblastic leukemia antigen (CALLA). The authors assessed the use of p63 and CD10 in the differential diagnosis between benign sclerosing lesions, such as sclerosing adenosis and radial scar, and tubular carcinoma, in comparison to the traditional myoepithelial markers 1A4 and calponin. p63, CD10, 1A4, and calponin were expressed in myoepithelial cells of all benign lesions and were consistently negative in all cases of tubular carcinoma. In contrast to cytoskeletal proteins, p63 and CD10 were mostly confined to myoepithelial cells and thus were more specific than the traditional counterparts. However, 1A4 was more intensely expressed and more reproducible than the novel markers. In conclusion, p63 and CD10 may be used as a complement to 1A4 in distinguishing benign sclerosing lesions from tubular carcinoma of the breast.

Seizures and cerebral schistosomiasis.

BACKGROUND: Schistosoma mansoni is a parasitic trematoid worm that infects humans. Schistosomiasis is endemic in parts of South America, sub-Saharan Africa, the Middle East, and some Caribbean islands. Disorders of the liver and gastrointestinal tract are the most common clinical manifestations. The central nervous system is not usually affected. The most common neurologic manifestation is transverse myelitis. In some circumstances, the eggs of S. mansoni are found in the brain, causing inflammatory reaction. OBJECTIVE: To describe a young Brazilian patient with partial epileptic seizures caused by a granulomatous lesion due to S. mansoni. CONCLUSION: In endemic areas or in patients with a positive epidemiological history, schistosomiasis must be considered as a possible diagnosis of seizures, particularly when they are associated with granulomatous lesions on magnetic resonance imaging.

Superoxide dismutase isoforms 1 and 2 in lumbar spinal cord of neonatal rats after sciatic nerve transection and melatonin treatment.

Oxidative stress has been implicated in motoneuron death secondary to axotomy in the neonatal period. We studied the effect of sciatic transection at P2 on the motoneuron population in the lumbar enlargement of newborn rats looking for a protective role of daily doses of the antioxidant melatonin. The animals were allowed to survive from P2 to P7, and the spinal cords were processed for immunohistochemistry for superoxide dismutase (SOD) isoforms 1 and 2 and nitric oxide synthase (nNOS) (at 2, 3, 5, and 7 days post-natum), histological neuron counting and immunoblotting for the SOD isoforms (both at 2, 3, and 7 days post-natum). Melatonin reduced by 75% motoneuron loss due to axotomy at P3 and P7. Neither sciatic transection nor melatonin induced any detectable changes in the immunoreactivity patterns of the enzymes. SOD1 was expressed diffusely in the cytoplasm of neurons and ependyma and in the nuclei of presumed glial cells from P2 to P7. SOD2 was detected in neurons and ependyma and its expression was similar to SOD1 at P2 but decreased later to a spotty cytoplasmic pattern in motoneurons. nNOS was localized to the cytoplasm of a few small cells in the ventral and dorsal horns and around the central canal. Immunoblotting at 1 day postaxotomy detected a significant increase in SOD1 expression in melatonin-treated axotomized rats and a decrease in controls after axotomy and vehicle. Blotting for SOD2 did not show significant changes between groups at any time. This study provides the first evidence that SOD2 immunostaining pattern varies during motoneuron postnatal development and that melatonin alters the expression of SOD1 in the present model of peripheral nerve injury.

Acute local nerve lesions induced by Bothrops jararacussu snake venom.

Myonecrosis is one of the most common effects of Bothrops jararacussu venom, but little is known about the action of this venom on other tissues. In this study, we used transmission electron microscopy to examine the influence of B. jararacussu venom on nerve tissue. A sublethal dose of venom (80 microg) was injected into the tibialis anterior muscle of mice which were then killed at various intervals up to 6 h after venom injection. The venom caused massive, progressive axonal damage beginning 2 min after inoculation and after 6 h, all intramuscular nerve bundles were completely depleted of nerve fibers. The most striking finding was myelin breakdown. The ultrastructural changes observed and the time course of the nerve lesions indicated that B. jararacussu venom acted directly on nerve tissue, possibly on the phospholipids of the myelin sheath. The axonal damage reported here may be of relevance to explain, at least in part, the muscular atrophy and poor recovery in muscle function seen in human and experimental envenomations.

Neuroprotective action of melatonin on neonatal rat motoneurons after sciatic nerve transection.

The neuronal isoform of nitric oxide synthase (nNOS), a NADPH-dependent diaphorase, is considered to play a role in motoneuron death induced by sciatic nerve transection in neonatal rats. Neuronal loss in these circumstances has been correlated with nitric oxide (NO) production and NADPH-diaphorase positivity in motoneurons after axotomy. In the present study we looked for a possible protective effect of melatonin, an antioxidant agent and inhibitor of nNOS, on spinal motoneurons after axonal injury. Neonatal Wistar rats (P2) were submitted to sciatic nerve transection and allowed to survive to P7. Melatonin at doses of 1, 5, 10, 50 and 100 mg/kg was given subcutaneously before and at intervals after the surgery. Controls operated in the same way received dilution vehicle or no treatment. The animals were killed by perfusion of fixative and the spinal cord was examined in serial paraffin sections. The motoneurons of the sciatic pool were counted in the axotomized and contralateral sides. Immunohistochemistry for nNOS and glial fibrillary acidic protein was used to evaluate nNOS expression in the axotomized cells and the astrocytic response. We found that melatonin at doses of 1-50 mg/kg decreased neuronal death. Astrocytic hypertrophy in melatonin treated animals was less intense. There were no differences in nNOS expression between treated and control rats, and surviving motoneurons of the sciatic pool did not express the enzyme, suggesting that nNOS may not be involved in neuronal death or survival in these experimental conditions. Possible mechanisms of melatonin neuroprotection, which was equally effective at doses of 1-50 mg/kg, are discussed. Doses of 50 and 100 mg/kg caused failure to thrive, seizures or death. The fact that neuroprotective doses were far smaller than toxic ones should encourage testing of melatonin in neurologic diseases.