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Lysosome-associated membrane protein (LAMP)-1, one of the major protein components of the lysosomal membrane, is upregulated in the human glioblastoma cell lines, U-373 MG and LN-Z308, which undergo cisplatin-induced apoptosis. These human brain tumor cell lines demonstrated apoptosis in response to cisplatin/nifedipine treatment. Both cell lines demonstrated an apoptotic response by more than one criterion. Apoptosis was demonstrated by DNA fragmentation techniques such as DNA laddering, ApopTag in situ labeling, and an ELISA-based method of detecting liberated oligosomes. These cells also had characteristic morphologic changes and upregulation of bax consistent with apoptosis. LAMP-1 expression at the protein and mRNA level was examined and found to increase with cisplatin/nifedipine treatment. LAMP-1 expression was examined using indirect immunofluorescent staining, Northern blot analysis and Western blot analysis. The finding of an augmentation of LAMP-1 in these cells induced to die is enigmatic. These findings raise the possibility of LAMP-1 involvement in the apoptotic process.

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Apoptosis has been implicated recently as a prominent response of the brain to a variety of insults, such as ischemia and trauma. In this study, we demonstrate that apoptosis is a prominent part of the brain's response to a thermal insult. To examine the brain's response to a thermal insult, a new model of thermal brain injury in the laboratory rat was developed. Water heated to 60 degrees C was passed over an area of thinned calvarium for 1 min. This resulted in an actual brain temperature of 47-48 degrees C. A uniform area of 2,3,5-triphenyl-tetrazolium chloride pallor was demonstrated and pyknotic neurons were seen in the area of injury by hematoxylin-eosin staining. Apoptosis was demonstrated by the characteristic DNA fragmentation seen by agarose gel electrophoresis, ApopTag in situ staining and electron microscopy. The findings of apoptosis were localized to the area of thermal injury and were time dependent, starting 6 h after the insult and peaking approximately 18 h after the insult. This represents one of the first demonstrations that apoptosis occurs in the brain in response to a thermal injury.

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OBJECTIVE AND IMPORTANCE: Oncocytoma in the central nervous system is extremely unusual. The first reported example of oncocytoma in a melanocytoma of the spinal cord was successfully excised, and its pathological appearance is described. CLINICAL PRESENTATION: A 71-year-old woman presented with a 25-year history of back pain and myelographic evidence of a lumbar spinal cord mass. After declining surgical treatment for two decades, she elected eventually to have the mass excised. Preoperative magnetic resonance imaging revealed a large intraspinal mass that spanned spinal levels L3 through S1. TECHNIQUE: The mass was excised en bloc through posterior laminectomies, and histopathological analysis revealed a benign neoplasm composed predominantly of monotonous sheets of plump oncocytes. Electron microscopy confirmed that the cytoplasm of the oncocytes was packed full of mitochondria. Focal areas of the tumor contained spindle cells, with abundant intracytoplasmic granular deposits of brown melanin pigment that contained melanosomes. Positive Fontana-Masson, HMB-45, and S-100 staining confirmed the final diagnosis of melanocytoma, oncocytic variant. CONCLUSION: The first reported case of oncocytoma arising in spinal melanocytoma is described. After surgical excision, the patient recovered completely and has remained free of symptoms for 4 years.

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There are relatively few reports that evaluate the cognitive functions of patients with arachnoid cysts. Presumably, these 'silent cysts' are regarded as incidental findings with no functional significance. Although postoperative clinical improvement is well documented in patients with significant reduction in cystic volume, the current report describes a patient who underwent cystoperitoneal shunting due to mass effect, with minimal postoperative decompression. Neuropsychological testing indicated significant cognitive improvement in verbal learning, memory, visual-perceptual abilities, constructional skills, conceptual shifting, and psychomotor speed after shunt placement, despite marginal evidence of decompression. These findings suggest that (1) significant cognitive changes can occur in these patients, despite minimal postoperative regression of the lesion, (2) cognitive measures may provide an alternative, functional index of outcome efficacy, and (3) reliance on traditional outcome measures (i.e. anatomical decompression or resolution of clinical symptoms) may underestimate the efficacy of surgical intervention for these patients.

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A synthetic five-part molecular device has been prepared that uses a multistep electron transfer strategy similar to that of photosynthetic organisms to capture light energy and convert it to chemical potential in the form of long-lived charge separation. It consists of two covalently linked porphyrin moieties, one containing a zinc ion (P(Zn)) and the other present as the free base (P). The metailated porphyrin bears a carotenoid polyene (C) and the other a diquinone species (Q(A)-Q(B)). Excitation of the free-base porphyrin in a chloroform solution of the pentad yields an initial charge-separated state, C-P(Zn)-P(.+).-Q(A)(-)-Q(B), with a quantum yield of 0.85. Subsequent electron transfer steps lead to a final charge-separated state, C(.+)-P(Zn)-P-Q(A)-Q(B)(.-), which is formed with an overall quantum yield of 0.83 and has a lifetime of 55 microseconds. Irradiation of the free-base form of the pentad, C-P-P-Q(A)-Q(B), gives a similar charge-separated state with a lower quantum yield (0.15 in dichloromethane), although the lifetime is increased to approximately 340 microseconds. The artificial photosynthetic system preserves a significant fraction ( approximately 1.0 electron volt) of the initial excitation energy (1.9 electron volts) in the long-lived, charge-separated state.