Frizzled 1 and Wnt1 as new potential therapeutic targets in the traumatically injured spinal cord

Despite the experimental evidence pointing to a significant role of the Wnt family of proteins in physiological and pathological rodent spinal cord functioning, its potential relevance in the healthy and traumatically injured human spinal cord as well as its therapeutic potential in spinal cord injury (SCI) are still poorly understood. To get further insight into these interesting issues, we first demonstrated by quantitative Real-Time PCR and simple immunohistochemistry that detectable mRNA expression of most Wnt components, as well as protein expression of all known Wnt receptors, can be found in the healthy human spinal cord, supporting its potential involvement in human spinal cord physiology. Moreover, evaluation of Frizzled (Fz) 1 expression by double immunohistochemistry showed that its spatio-temporal and cellular expression pattern in the traumatically injured human spinal cord is equivalent to that observed in a clinically relevant model of rat SCI and suggests its potential involvement in SCI progression/outcome. Accordingly, we found that long-term lentiviral-mediated overexpression of the Fz1 ligand Wnt1 after rat SCI improves motor functional recovery, increases myelin preservation and neuronal survival, and reduces early astroglial reactivity and NG2+ cell accumulation, highlighting the therapeutic potential of Wnt1 in this neuropathological situation.

Cells in the adult human spinal cord ependymal region do not proliferate after injury

In vertebrates that regenerate the injured spinal cord, cells at the ependymal region proliferate and coordinate the formation of bridges between the lesion stumps. In mammals, these cells also proliferate profusely around the central canal after spinal cord injury, although their actual contribution to repair is controversial. In humans, however, the central canal disappears from early childhood in the majority of individuals, being replaced by astrocyte gliosis, ependymocyte clusters, and perivascular pseudo-rosettes. In this human ependymal remnant, cells do not proliferate under normal conditions, but it is not known if they do after a lesion. Here, we studied the human ependymal remnant after traumatic spinal cord injury using samples from 21 individuals with survival times ranging from days to months post-injury. With three different monoclonal antibodies raised against two different proliferation markers (Ki67 and MCM2), we found that the ependymal remnant in adult humans does not proliferate after injury at any time or distance from the lesion. Our results seriously challenge the view of the spinal cord ependymal region as a neurogenic niche in adult humans and suggest that it would not be involved in cell replacement after a lesion. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Human Schwann cells exhibit long-term cell survival, are not tumorigenic and promote repair when transplanted into the contused spinal cord

The transplantation of rodent Schwann cells (SCs) provides anatomical and functional restitution in a variety of spinal cord injury (SCI) models, supporting the recent translation of SCs to phase 1 clinical trials for human SCI. Whereas human (Hu)SCs have been examined experimentally in a complete SCI transection paradigm, to date the reported behavior of SCs when transplanted after a clinically relevant contusive SCI has been restricted to the use of rodent SCs. Here, in a xenotransplant, contusive SCI paradigm, the survival, biodistribution, proliferation and tumorgenicity as well as host responses to HuSCs, cultured according to a protocol analogous to that developed for clinical application, were investigated. HuSCs persisted within the contused nude rat spinal cord through 6 months after transplantation (longest time examined), exhibited low cell proliferation, displayed no evidence of tumorigenicity and showed a restricted biodistribution to the lesion. Neuropathological examination of the CNS revealed no adverse effects of HuSCs. Animals exhibiting higher numbers of surviving HuSCs within the lesion showed greater volumes of preserved white matter and host rat SC and astrocyte ingress as well as axon ingrowth and myelination. These results demonstrate the safety of HuSCs when employed in a clinically relevant experimental SCI paradigm. Further, signs of a potentially positive influence of HuSC transplants on host tissue pathology were observed. These findings show that HuSCs exhibit a favorable toxicity profile for up to 6 months after transplantation into the contused rat spinal cord, an important outcome for FDA consideration of their use in human clinical trials.

Primary carcinoid tumor of the cavernous sinus

BACKGROUND

Intracranial carcinoid tumors belong to the class of neuroendocrine tumors and their incidence is extremely rare. The pathogenesis and clinical manifestations of carcinoid tumors of the skull base are outlined in this case report.

CASE DESCRIPTION

A 61-year-old multimorbid woman presented with transient memory loss. Computed tomographic and magnetic resonance imaging scan of the brain demonstrated a left cavernous sinus mass extending into the infratemporal fossa. The lesion was biopsied using the Caldwell-Luc approach, and histology showed a low-grade neuroendocrine tumor. The tumor was subtotally resected with a neurosurgery/head and neck combined preauricular infratemporal and subtemporal extradural approaches to the cavernous sinus. Further histologic evaluation revealed that the tumor was of carcinoid differentiation with no other primary or metastatic sites detectable.

CONCLUSION

Primary intracranial carcinoid tumors, though rare, should be included in the differential diagnosis of extradural and dural-based lesions.

Intraosseous schwannoma of the petrous apex

Primary neoplasms of the petrous apex are rare and include eosinophilic granuloma, chondroma, chondrosarcoma, chordoma, and schwannoma. We report just the second published case of an intraosseous schwannoma of the petrous apex and are the first to describe the entity using magnetic resonance imaging. By studying the computed tomography and magnetic resonance imaging features of this rare tumor, it is possible to suggest the diagnosis preoperatively.

Postoperative fibrosis after surgical treatment of the porcine spinal cord: a comparison of dural substitutes

Object. Postoperative adhesion- and fibrosis-induced spinal cord tethering is not uncommon and may be associated with delayed clinical sequelae. Multiple dural substitutes have been used in surgery without a full appreciation of the grafts' adverse effects. The authors conducted a comparative animal experimental study to evaluate the degree of chronic inflammatory reactions, adhesions, and fibrosis caused by the use of four dural substitutes—Surgicel, Durasis, DuraGen, and Preclude.

Methods. Twenty-six pigs weighing 30 to 40 kg underwent a two-level lumbar laminectomy (a midline durotomy, implantation of a 2-cm dural substitute in the subarachnoid space, and watertight dural closure). After 8 weeks the animals were killed, and two independent neuropathologists blinded to the dural substitute group evaluated several sites along the implants, providing descriptions and quantitative scoring of fibrosis, chronic inflammatory reactions, foreign-body reactions, and spinal cord changes. Kruskal—Wallis one-way analysis of variance for ranks corrected for multiple comparisons was used to examine differences among the materials.

Conclusions. The DuraGen dural substitute produced the least amount of inflammation in the subarachnoid space and Preclude generated the most (p < 0.001). Surgicel and DuraGen were completely resorbed on histological sections, but both produced some inflammation, which diminished gradually from the dural implant center. Histological evaluation of the nonresorbed grafts demonstrated that Durasis caused the least degree of inflammatory cell infiltration (p < 0.001). The Preclude dural substitute consistently demonstrated encapsulation and arachnoidal reaction. There was no evidence of implant-related adverse effects on the underlying pia mater and white matter regardless of the substitute type.

Benign focal cerebral vasculitis: case report

We report a 47-year-old man who presented with partial seizures complicating focal cerebral vasculitis of the right temporal lobe. Excisional biopsy of the mass lesion revealed fibrinoid necrosis of small vessels. These vessels were infiltrated by neutrophils, eosinophils, lymphocytes, and plasma cells. Despite extensive evaluation, no etiology was apparent for the vasculitis. No immunosuppressive agents were administered, and 4 1/2 years after the diagnosis, he remains healthy except for an incongruous left homonymous hemianopia. Follow-up cranial magnetic resonance images revealed only postoperative changes. This case demonstrates that focal lesions and a benign course may represent one end of the spectrum of primary angiitis of the central nervous system.

Severe cerebral edema in a patient with anasarca and hypernatremia

We describe a woman whose fatal post-liver transplantation cerebral edema was unexpected and of unusual pathogenesis. Her severe cerebral edema is of considerable pathophysiologic interest: 1) it developed in the setting of marked anasarca and persistent hypernatremia, and 2) although hepatic function was poor, it was not considered sufficiently deranged to induce cerebral edema. Furthermore, there was no histologic evidence of hepatic rejection or antemortem hepatic necrosis. We postulate that an impairment of the blood brain barrier in association with a degree of hepatic dysfunction insufficient by itself to cause cerebral edema permitted the brain interstitial fluid volume to increase pari passu with ECF expansion. Cytotoxic cerebral edema and vascular engorgement may also have contributed to a life-threatening increase in intracranial pressure.

Acute traumatic central cord syndrome: MRI-pathological correlations

The acute traumatic central cord syndrome (ATCCS) is commonly stated to result from an injury which affects primarily the center of the spinal cord and is frequently hemorrhagic. To test the validity of this widely disseminated hypothesis, the magnetic resonance images [MRI] of 11 consecutive cases of ATCCS caused by closed injury to the spine were analyzed and correlated with the gross pathological and histological features of 3 cervical spinal cords obtained at post mortem from patients with ATCCS, including 2 of patients studied by MRI. The MRI studies were performed acutely (18 h to 2 days after injury) in 7 patients and subacutely (3-10 days after injury) in 4. Ten of the 11 patients had pre-existing spondylosis and/or canal stenosis. The 11th suffered a cervical fracture. All patients exhibited hyperintense signal within the parenchyma of the cervical spinal cord on gradient echo MRI. None showed MRI features characteristic of hemorrhage on T1-weighted spin echo or T2-weighted gradient echo studies. Gross and histological examination of the necropsy specimens showed no evidence of blood or blood products within the cord parenchyma: the primary finding was diffuse disruption of axons, especially within the lateral columns of the cervical cord in the region occupied by the corticospinal tracts. The central gray matter was intact. In patients with ATCCS, the predominant loss of motor function in the distal muscles of the upper limbs may reflect the importance of the corticospinal tract for hand and finger function in the primate. In this study, the MRI and pathological observations indicate that ATCCS is predominantly a white matter injury and that intramedullary hemorrhage is not a necessary feature of the syndrome; indeed, it is probably an uncommon event in ATCCS. We suggest that the most common mechanism of injury in ATCCS may be direct compression of the cervical spinal cord by buckling of the ligamenta flava into an already narrowed cervical spinal canal; this would explain the predominance of axonal injury in the white matter of the lateral columns.

Meningioangiomatosis: clinical, radiologic, and histopathologic correlation

Meningioangiomatosis (MA) is a rare, benign, hamartomatous lesion of the leptomeninges; MA has been considered to be a forme fruste of neurofibromatosis. A review of pathology records for patients with MA who were seen between 1970 and 1989 at the authors' institutions revealed four patients (three male and one female; aged 2.5-21.0 years; mean, 10.8 years) with a history of seizures but without the stigmata or family history of neurofibromatosis. Three patients had undergone either computed tomographic (CT) or magnetic resonance (MR) imaging studies. All patients had undergone craniotomies to obtain tissue for pathologic analysis; a peripheral, leptomeningeal lesion was found in all four patients. At CT in two patients, the lesions were most consistent with calcification. At T2-weighted MR imaging in one patient, the lesion demonstrated a hyperintense periphery with associated edema of the white matter. Histopathologic examination demonstrated characteristic features of MA--cortical meningovascular fibroblastic proliferation and leptomeningeal calcification. The accurate diagnosis of MA is important since MA is a benign, surgically correctable cause of seizures.

Cerebrovascular disease in AIDS: a case-control study

The autopsy records of adult patients dying with AIDS between 1983 and 1987 at a large, metropolitan, university-affiliated hospital were reviewed to determine the incidence and spectrum of cerebrovascular and associated cardiovascular disease. The clinical records of those patients with AIDS with cerebrovascular disease were retrospectively examined in detail. All autopsied patients between the ages of 20 and 50 years dying without AIDS in 1986 and 1987 served as the control group. At autopsy, 13 (8%) of 154 adult patients with AIDS had evidence of recent cerebrovascular disease. In comparison, 25 (23%) of the 111 control patients dying without AIDS had recent cerebrovascular disease (P less than 0.04). The spectrum of cerebrovascular diseases was similar in patients both with and without AIDS; however, cerebral vasculitis was observed only in the former. Thirty-nine (40%) of 97 patients with AIDS had significant cardiac disease, and cerebral emboli were demonstrated in four of the 13 patients with stroke. Stroke must be considered in the differential diagnosis of neurological disease in patients with AIDS, although it does not appear to be more common in this group than in a control population of young adults with other terminal illnesses. The causes of stroke occurring with AIDS are diverse and include cerebral emboli secondary to cardiac disease, cerebral hemorrhage secondary to thrombocytopenia, and cerebral vasculitis.

Multifocal fibrosclerosis with hypertrophic intracranial pachymeningitis

We describe a 34-year-old man with a 17-year history of multifocal fibrosclerosis resulting in unique neurologic complications. Episcleritis, orbital pseudotumor, and sclerosing cholangitis accompanied a florid intracranial inflammatory pachymeningitis. The latter was associated with blindness, multiple cranial neuropathies, pseudotumor cerebri, and seizures. Extensive investigation failed to reveal an etiology. Corticosteroids were ineffective in preventing progression of the disorder, and the value of antineoplastic therapy was uncertain. Multifocal fibrosclerosis, a rare disorder, may result in a confusing array of neurologic manifestations.

Multiple sclerosis-like illness occurring with human immunodeficiency virus infection

We describe seven men with a neurologic disease clinically indistinguishable from multiple sclerosis occurring in association with seropositivity for the human immunodeficiency virus, type 1 (HIV-1). Histopathology of the CNS obtained in three patients (2 by brain biopsy, 1 at autopsy) was consistent with MS. The neurologic symptoms preceded the onset of clinically evident immunosuppression in all patients. In three men, HIV-1 seropositivity was demonstrated concomitantly or within 3 months of the onset of their neurologic disease. In the others, features of MS preceded the demonstration of HIV-1 seropositivity by 41 months, 59 months, 11 years, and 18 years, respectively. Despite the superimposition of varying degrees of cellular immunodeficiency associated with HIV-1 infection, six of these men continued to experience relapsing neurologic symptoms.

Computerized tomography in the diagnosis of central and extrapontine myelinolysis

In two patients the diagnosis of central pontine myelinolysis (CPM), suspected on clinical grounds, was supported by computerized tomographic (CT) sections made perpendicular to the pons, and confirmed on postmortem examination. Extrapontine myelinolysis was suggested on CT scans in both cases, and confirmed in one. Computerized tomography may prove to be a sensitive and accurate diagnostic test for CPM, and may aid in the detection of associated extrapontine lesions.

Individual transparency patterns of adhesive-tape strip series of the stratum corneum

A newly developed apparatus permits the differentiated transparency measurement of stripped horny layer material. An adhesive tape strip, covered with a stripped horny layer mass, is fixed on a glass plate and led past a homogenous light source and a photo cell at a constant speed, whereby each respective light-current deviation is collected as a parameter for each respective strip model. It is then synchronously registered via a continuous-line-recorder. The systematic evaluation of original curves results in a reproducible individual horny layer model obtained by a methodically stripped adhesive tape series, successively taken under constant conditions from the same skin area. Three characteristic types of curves were observed.