One of the most important recent observations in traumatic brain injury (TBI) relates to the potential role of apoptosis in secondary brain injury. We aimed to analyze the presence of apoptosis and the expression of apoptosis-related proteins in brain samples from patients with TBI. We also tried to find any association between the in situ results and the in vitro observations in a neuronal model of induced-apoptosis. Brain tissue from the pericontusional zone (PCZ) of patients with traumatic contusions and from post-mortem samples was analyzed. Immunohistochemical analyses of apoptosis-related proteins and the terminal deoxynucleotide transferase-mediated nick end labeling (TUNEL) method to determine the presence of apoptotic cells were performed. Apoptotic rates on neuronal cells induced by jugular bulb vein sera was determined by flow cytometry. TUNEL-positive cells were detected in all PCZ of traumatic contusions and in most of PCZ in post-mortem specimens (none in control; p = 0.026). In vivo samples showed higher expression of antiapoptotic proteins Bcl-2 (p = 0.027) and Bcl-XL (p = 0.014) than post-mortem samples. In autopsies, the expression of Fas and Bim (p < 0.05) were higher in PCZ than in the zone distal from the contusion. In vitro studies showed that apoptotic rate was an independent factor associated with mortality at 6 months (p = 0.014). In the receiving operator curve (ROC) curve, a cut-off point of 66.5% showed a sensitivity of 89.5% and specificity of 66.7% in the prediction of patients' death. Cerebral apoptosis is a prominent form of cell death in the PCZ of human traumatic cerebral contusions, and high rates of in vitro apoptosis are associated with a poorer prognosis after TBI.
A family with hereditary motor and sensory neuropathy (HMSN) type II is described in which 10 affected and 17 unaffected members in three generations were examined. The peak age of onset was in the second decade. In the youngest generation, the proportion of affected to unaffected individuals at risk significantly differed from the expected 50%. There was slight slowing of conduction velocities in 36% of nerves; however, only 3 out of 10 affected members had entirely normal conduction studies. The amplitude of the sensory potentials of median and peroneal nerves was almost uniformly reduced. In all affected patients electromyography of anterior tibial muscles showed signs of neurogenic involvement. Histological study of two sural nerves and a sciatic nerve and its branches revealed loss of myelinated fibres with a proximal-to-distal gradient in this fibre loss, clusters of small regenerating fibres, and atrophic axons. Postmortem study of the proband showed loss of anterior horn and dorsal root ganglion neurons in the lumbar and sacral segments and degeneration of the fasciculus gracilis. Morphometric evaluation of L5 ventral and dorsal roots revealed a normal number of myelinated fibres, diameter histograms being shifted to the left because of a significant loss of large myelinated fibres and regeneration. These anatomical findings are consistent with the hypothesis that HMSN type II represents a primary neuronopathy affecting motor and sensory neurons.
The pathological basis of nerve inexcitability in GuillainBarré syndrome has not been established with certainty. We report the clinicopathological findings in a 67-year-old patient with fulminant GuillainBarré syndrome who died 18 days after onset. Three serial electrophysiological studies revealed nerve inexcitability. Antibodies to Campylobacter jejuni were present but there was no antiganglioside reactivity. Spinal root sections revealed extensive and almost pure macrophage-associated demyelination with occasional presence of T lymphocytes and neutrophil leukocytes. Conversely, in femoral, median, and sural nerves the outstanding lesion was axonal degeneration, with some denuded axons remaining. Unmyelinated fibers, posterior root ganglia, and dorsal columns were preserved. Endoneurial postcapillary venules showed plump endothelial cells with loss of their tight junctions. We conclude that both primary demyelination and axonal degeneration secondary to inflammation account for nerve inexcitability. Our findings lend support to the hypothesis of increased endoneurial pressure as the cause of wallerian degeneration in nerve trunks. The Guillain-Barré syndrome (GBS) is an acute or subacute evolving paralytic disease of unestablished etiology with characteristic pathological features of macrophage and lymphocytic infiltration of peripheral nerve with myelin destruction. 2,3 Nerve conduction studies reveal the typical findings of an acute multifocal demyelinating polyradiculoneuropathy consisting of proximal or distal conduction block and slowing of conduction. 1,9,16,39,46,62 In a small proportion of GBS cases, however, one or more peripheral nerves are inexcitable. 1,62,72,73 Because of the scarcity of detailed autopsy studies, 5,[18][19][20]75 the pathological basis of nerve inexcitability in GBS is controversial, three explanations being possible: distal demyelination with conduction block, secondary wallerian degeneration following demyelination, or primary and severe axonopathy. 5,10,[18][19][20]49,72,73,75 Serial electrophysiological studies have shown that conduction block, the physiological hallmark of demyelination, often precedes the appearance of axonal degeneration. 72,73 Exceptionally inexcitable nerves may be an early and inaugural electrophysiologic feature which has been related to axonal degenera-
We report four cases of Scedosporium inflatum (S. inflatum) infection in severely immunocompromised haematological patients. Six well-documented cases of S. inflatum disseminated infection in haematological patients have been reported: four in Australia and two in Spain. Their clinical and pathological characteristics are heterogenous, particularly in the Australian cases. However, the clinical and pathological profile emerging from our and other Spanish cases is homogenous and very similar to the clinico-pathological spectrum of other disseminated mycoses, including Aspergillus and S. apiospermum. The optimal treatment of S. inflatum infection is unknown and the outcome in haematological patients is very poor. Eight patients died despite systemic antifungal treatment.
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