Halting hyaluronidase activity with hyaluronan-based nanohydrogels: development of versatile injectable formulations

Hyaluronan (HA) is among the most used biopolymers for viscosupplementation and dermocosmetics. However, the current injectable HA-based formulations present relevant limitations: I) unmodified HA is quickly degraded by endogenous hyaluronidases (HAase), resulting in short lasting properties; II) cross-linked HA, although shows enhanced stability against HAase, often contains toxic chemical cross-linkers. As such, herein, we present biocompatible self-assembled hyaluronan-cholesterol nanohydrogels (HA-CH NHs) able to bind to HAase and inhibit the enzyme activity in vitro, more efficiently than currently marketed HA-based cross-linked formulations (e.g. Jonexa™). HA-CH NHs inhibit HAase through a mixed mechanism, by which NHs bind to HAase with an affinity constant 7-fold higher than that of native HA. Similar NHs, based on gellan-CH, evidenced no binding to HAase, neither inhibition of the enzyme activity, suggesting this effect might be due to the specific binding of HA-CH to the active site of the enzyme. Therefore, HA-CH NHs were engineered into injectable hybrid HA mixtures or physical hydrogels, able to halt the enzymatic degradation of HA.

Prolonged Stabilization of Multiple and Single Brain Metastases from Breast Cancer with Tamoxifen. Report of Three Cases

Cancer frequently metastasizes to the brain, and such lesions, whether multiple or solitary, have a poor prognosis, despite all efforts to treat them. There have been recent sporadic reports of brain metastases from breast cancer responding for some years to antiestrogens (particularly tamoxifen) or bromocryptine. We report three cases of brain metastasis from cancer – two multiple and one a solitary lesion. The long survival of the patients – two for 5 years and one for 6 years, with more than an acceptable quality of life – should prompt therapeutic trials to test tamoxifen and designed to assess its effects on a sizable number of patients.

Post-Radiation Gliomas

Aims and background

Radiotherapy is important in the treatment of neoplasm of the central nervous system, but various side effects, particularly neoplastic, have been described. Recently, post-radiation gliomas have been reported.

Methods

The authors review 88 cases of cerebral glioma following radiotherapy in patients operated for neoplasms of the nervous system, including 6 personal cases of post-radiation gliomas treated in the Neurosurgical Division of the Department of Neurological Sciences, “La Sapienza” University, Rome. The criteria used to define this unusual pathologic association are discussed.

Results

There was a male predominance. Post-radiation gliomas were particularly malignant, the average dose was 33 Gy, and average free latency was 9.6 years. The first disease was most frequently acute lymphatic leukemia.

Conclusions

Post-radiation gliomas have particular features but do not present a histologic or clinical behavior different from analogous spontaneous gliomas. The fact that 88 cases have been reported in recent years suggests that a thorough biological, clinical studies be carried out on this association.

Association of Breast Carcinoma and Meningioma: Report of Nine New Cases and Review of the Literature

Nine patients with diagnosed breast cancer who developed meningiomas are reported. Articles suggesting that an association of these two tumors is possible. Some authors have noted hormonal sensivity and the presence of hormonal receptors in some meningiomas. Since breast cancer is the most common tumor in women, an association between it and meningiomas might be fortuitous. However, it is important to fully investigate brain lesions in patients with breast cancer so that potentially curable meningiomas are not considered as metastases.

Solitary Brain Metastases from Thyroid Carcinoma: Study of 6 Cases

Aims and background

Although systemic metastases from thyroid cancer are relatively frequent, they rarely affect the nervous system and only exceptionally originate from well-differentiated carcinoma.

Methods

The authors describe 6 cases of solitary brain metastases from thyroid carcinoma, well-differentiated in 3 cases and anaplastic in the other 3 cases.

Results

Four patients were females and 2 males (M:F ratio, 1:2); average age was 51 yrs (range 48-56). On average, the interval between diagnosis of the thyroid tumor and appearance of the metastasis was 2.8 years (range 1-12 years) and was shorter in the anaplastic forms (1.2 versus 4.4 years). Average survival was 15 months (range 6-48 months); in particular, average survival was longer in patients with well-differentiated carcinoma (9 vs 21 months) as also in those who did not present other metastatic sites (6 vs 24 months). Death was due to systemic progression of the disease in 4 cases and to brain-relapse in the other 2 cases.

Conclusions

Surgery, radioactive iodine (where uptake is demonstrable), and radiotherapy are the main therapies available for metastases from thyroid carcinoma. However, survival of patients appears to be modified by the type of treatment performed.

Ossifying Fibroma of the Skull: Clinical and Therapeutic Study

Aims and Backround

Ossifying fibroma is a tumor with benign course that rarely affects the cranial bones.

Methods

The authors report 5 cases of ossifying fibroma of the skull and analyze the clinical course and treatment of this lesione.

Results

3 patients were females and 2 males. The mean clinical history was 3.2 years. 4 patients underwent total removal and 1 partial. At mean follow-up of 19 years, all patients who underwent total removal showed improvement of neurological deficit, whereas the patient who underwent partial removal had clinical regrowth.

Conclusion

The authors conclude that total removal of fibroma should be extended to normal bone and in cases in which total removal is not possible the residue should be checked for regrowth by serial MRI.

Intramedullary Teratoma: Case Report and Review of the Literature

Aims and Background

Intramedullary teratoma is an extremely exceptional tumor (5 cases), although a careful review of international literature has shown it to be more frequent (32 cases) than believed.

Methods

The authors present a personal case with some unusual aspects.

Results

Our case is unusual not only because it was diagnosed by MRI (only one case has been reported in the literature) but also because surgical removal of the tumor was apparently total (only 4 other cases have been described), with a long follow-up period (4.5 years) and excellent results, in clinical and neuroradiologic terms.

Carcinoma of the Prostate: Brain Stem Metastasis as the Only Site of Spread

Aims and background

Metastasis to the brain from prostate carcinoma is a rare event; it is reported in less than 4% of postmortem examinations. The prevalence of cases detected antemortem is even smaller, and the prevalence of brain stem metastasis as the only site of metastasis has been reported in only two other cases.

Method

The authors present a third such case.

Results

A 55-year-old man, treated for an adenocarcinoma of the prostate (prostatectomy and radiotherapy), started to complain of facial expression disturbances and headaches 2 years later. Physicial examination showed a left VII cranial nerve palsy. MRI showed an enhancing mass in the pons. Total body CT was negative. The patient was treated with a course of whole-brain and brain stem radiotherapy following stereotactic biopsy. Four months after radiotherapy, the neurological symptoms had disappeared and the patient died of a myocardial infarct. The systemic disease was still clinically silent.

Conclusion

Our case involved only brain stem metastasis, probably implicating Batson's direct route of the paravertebral venous pathway.

Open tubular columns containing the immobilized ligand binding domain of peroxisome proliferator-activated receptors α and γ for dual agonists characterization by frontal affinity chromatography with mass spectrometry detection

The peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily. In the last years novel PPARs ligands have been identified and these include PPARα/γ dual agonists. To rapidly identify novel PPARs dual ligands, a robust binding assay amenable to high-throughput screening toward PPAR isoforms would be desirable. In this work we describe a parallel assay based on the principles of frontal affinity chromatography coupled to mass spectrometry (FAC-MS) that can be used to characterize dual agonists. For this purpose the ligand binding domain of PPARα receptor was immobilized onto the surface of open tubular capillaries to create new PPAR-alpha-OT columns to be used in parallel with PPAR-gamma-OT columns. The two biochromatographic systems were used in both ranking and Kd experiments toward new ureidofibrate-like dual agonists for subtype selectivity ratio determination. In order to validate the system, the Kd values determined by frontal analysis chromatography were compared to the affinity constants obtained by ITC experiments. The results of this study strongly demonstrate the specific nature of the interaction of the ligands with the two immobilized receptor subtypes.

Quaternary structure of Dictyostelium discoideum nucleoside diphosphate kinase counteracts the tendency of monomers to form a molten globule

Multimeric enzymes that lose their quaternary structure often cease to be catalytically competent. In these cases, conformational stability depends on contacts between subunits, and minor mutations affecting the surface of the monomers may affect overall stability. This effect may be sensitive to pH, temperature, or solvent composition. We investigated the role of oligomeric structure in protein stability by heat and chemical denaturation of hexameric nucleoside diphosphate kinase from Dictyostelium discoideum and its P105G mutant over a wide range of pH. The wild-type enzyme has been reported to unfold without prior dissociation into monomers, whereas monomer unfolding follows dissociation for the P105G mutant (Giartosio et al. (1996) J. Biol. Chem. 271, 17845-51). We show here that these features are also preserved at alkaline pH, with the wild-type enzyme always hexameric at room temperature whereas the mutant dissociates into monomers at pH >or=10. In acidic conditions (pH <or=6), even in the absence of denaturant, the predominant species for both proteins is an intermediate monomeric form with the characteristics of a molten globule: disordered tertiary native structure but preserved secondary structure. Monomers therefore seem to have a low intrinsic stability, which is overcome by the conformational organization in the oligomeric structure.

Binding of nucleotides to nucleoside diphosphate kinase: a calorimetric study

The source of affinity for substrates of human nucleoside diphosphate (NDP) kinases is particularly important in that its knowledge could be used to design more effective antiviral nucleoside drugs (e.g., AZT). We carried out a microcalorimetric study of the binding of enzymes from two organisms to various nucleotides. Isothermal titration calorimetry has been used to characterize the binding in terms of Delta G degrees, Delta H degrees and Delta S degrees. Thermodynamic parameters of the interaction of ADP with the hexameric NDP kinase from Dictyostelium discoideum and with the tetrameric enzyme from Myxococcus xanthus, at 20 degrees C, were similar and, in both cases, binding was enthalpy-driven. The interactions of ADP, 2'deoxyADP, GDP, and IDP with the eukaryotic enzyme differed in enthalpic and entropic terms, whereas the Delta G degrees values obtained were similar due to enthalpy--entropy compensation. The binding of the enzyme to nonphysiological nucleotides, such as AMP--PNP, 3'deoxyADP, and 3'-deoxy-3'-amino-ADP, appears to differ in several respects. Crystallography of the protein bound to 3'-deoxy-3'-amino-ADP showed that the drug was in a distorted position, and was unable to interact correctly with active site side chains. The interaction of pyrimidine nucleoside diphosphates with the hexameric enzyme is characterized by a lower affinity than that with purine nucleotides. Titration showed the stoichiometry of the interaction to be abnormal, with 9--12 binding sites/hexamer. The presence of supplementary binding sites might have physiological implications.

Spontaneous cerebellar hemorrhage: clinical remarks on 50 cases

BACKGROUND

Only during the past 10 years have spontaneous cerebellar hemorrhages became a well-defined nosological entity. The surgical indication remains debatable. Our primary objective in this study was to set the criteria for undertaking surgery by determining the critical diameter of the hematoma and considering the patients' neurological status (Glasgow Coma Scale).

METHODS

During the 8-year period 1990 through 1997 a series of 50 consecutive patients with spontaneous cerebellar hemorrhage were admitted to the Emergency Neurosurgery Unit, University of Rome "La Sapienza" (Italy). On admission all patients underwent a standard neurological examination, (Glasgow Coma Scale) and a computed tomographic scan. The diameter and the site of the hematoma, a coexisting tight posterior fossa, and the presence of hypertensive hydrocephalus were the criteria, in association with the patients' neurological status, used as indications for surgery.

RESULTS

Operative mortality was nil; and perioperative mortality eight patients (16%, increasing to 24% including the four patients who were deeply comatose on admission). Most patients who died (seven of eight) had two or more general medical risk factors (arterial hypertension and diabetes mellitus; arterial hypertension and liver disease; or liver disease and hematological disorders).

CONCLUSION

In patients presenting with spontaneous cerebellar hemorrhage the essential criteria indicating surgery are a hematoma 40 mm x 30 mm on CT imaging in the cerebellar hemisphere or 35 mm x 25 mm on CT imaging in the vermis, the presence of a tight posterior fossa (critical size reduced by 10 mm), and a Glasgow Coma Score less than 13.

Medulloblastoma in late adults. Case report and critical review of the literature

BACKGROUND

Medulloblastoma in late adults (older than 65 years) is an exceptional occurrence; in fact only 8 cases are reported with complete clinical notes in the literature.

METHODS

The authors describe a case of medulloblastoma occurring in a 68-year-old man and analyzed cases reported in the literature.

RESULTS

The overall average age of the patients was 72.8 years (range 67-88 years), and the male prevalence of this tumour (70% of cases) seems to be unrelated to age. There is a lateral predominance in late adults (77.7% of cases). Seven patients underwent operation and subsequently these patients underwent a course of radiation therapy. Only two patient was treated with postoperative chemotherapy. Median survival for seven patients treated was 43.2 months (range 23-96 months).

CONCLUSIONS

It is interesting to note that: 1) histological analysis revealed a classic type medulloblastoma (88.8% of cases) similar to the children: 2) site of the tumor is lateral similar to the adults (77.7% of cases).

DNA-protein cross-linking in nuclei of immature and mature chicken erythrocytes

DNA-protein cross-linkages were formed in isolated nuclei from immature and mature chicken erythrocytes by reaction with cis-diammine dichloroplatinum. On the basis of electrophoretic behaviour, the most abundant proteins involved in the cross-linking appeared to be present also in preparations of nuclear matrix. The maturation of the erythrocyte, which is accompanied by transcriptional inactivation, leads to a decrease in the amount of DNA-interacting proteins, to a loss of proteins capable of a specific recognition of DNA sequences and, unexpectedly, to the appearence of some new DNA-protein interactions. At least three cross-linked proteins were found predominantly or exclusively in nuclei of immature cells, and three others in those of mature ones. The three DNA-bound proteins, typical of mature erythrocytes, were not found among the components of a high-salt preparation of nuclear matrix. The results obtained suggest that, in addition to the well-known histone H5 and MENT protein, these newly identified DNA-bound proteins contribute to the formation of the condensed, inactive chromatin characteristic of mature erythrocyte.

An asymptomatic hypertrophic pacchionian granulation simulating osteolytic lesion of the calvaria

Osteolytic lesions can be seen in various diseases. We present a rare case of symptomatic hypertrophic pacchionian granulation mimicking bone tumor in the calvaria. A 50-year-old woman suffered from a previous VII cranial nerve peripheral paresis accompanied by headache. A plain radiograph revealed a punched-out paramedial occipital lesion. Precontrast-enhanced computed tomographic scans demonstrated a hypodense mass, with a defect of both tables of the left occipital bone. Magnetic resonance imaging (MRI) demonstrated a hypointense mass on the T1-weighted image and isointense to cerebrospinal fluid on the T2-weighted image, with capsule-like contrast enhancement by gadolinium. A biopsy was performed. Histologically, hypertrophic pacchionian granulation was diagnosed. The patient has had no growth for 2 years. This case suggests the need to include hypertrophic pacchionian granulation in the differential diagnosis of punched-out lesions.

Cross-linked telomere-protein complexes from chicken erythrocyte nuclei: isolation by a new procedure

DNA-protein cross-linkages were produced in intact nuclei of chicken erythrocytes by the action of cis-diammine dichloroplatinum. The telomeric DNA-protein cross-linked complexes were then isolated by hybridization with a biotinylated oligonucleotide and selective binding on immobilized streptavidin. Two main nonhistone proteins were present in the purified complexes, migrating in SDS-gel electrophoresis with apparent molecular masses of 66 and 58 kDa, respectively. Although the identity of these two proteins is still unknown, it is significant that two proteins with similar electrophoretic behavior have been described as constituents of the human telomeric complexes. This procedure could also be applied to the isolation of DNA-protein cross-linked complexes containing any chosen DNA sequence.

Cerebral metastasis from ovarian carcinoma. Some observations about treatment

Systemic metastases from ovarian carcinoma are frequent, but they rarely affect the central nervous system. The treatment of this type of metastases in not clear. Two cases of solitary cerebral metastasis from ovarian carcinoma are reported. Two patients, submitted to therapeutic protocol established for ovarian carcinoma, presented after 17 and 25 months respectively the appearance of symptoms from brain solitary metastasis without other metastases. They underwent surgery, radiotherapy and chemotherapy for solitary cerebral metastasis. Treatment of the brain lesion resulted in KPS improvement (KPS = 90) and survival was 16 and 30 months, respectively. From the 2 cases presented and the review of the literature, it appears that a better outcome may be obtained by a combined treatment of metastases, including surgery, radiotherapy and chemotherapy.

Solitary plasmacytoma of the calvarium: a review of clinical and prognostic features

Primary craniocerebral plasmacytomas are uncommon they represent only 0.7% of all plasmacytomas. We report one case of solitary plasmacytoma of the skull and discuss the clinical features and prognosis of this tumor. There seems to be no difference in prognosis between plasmacytomas originating from the bone (osseous form) and those originating from the dura mater (non-osseous form). In these lesions, the risk of secondary multiple myeloma appears to be low.

Intraosseous schwannoma of the vault of the skull

Intraosseous schwannoma is a rare benign tumor of the bone with characteristic radiological and histological features. The most common sites of this tumor are mandible, sacrum, und vertebral bodies. Two cases, one of which is the first diagnosed with MRI, of this tumor in the vault of the skull are presented.

[Therapeutic considerations in solitary cerebral metastases from uterine carcinoma]

Brain metastases from endometrial carcinoma rarely involve the nervous system and are solitary in exceptional cases (< 1% of cases). Two cases of solitary cerebral metastasis from endometrial carcinoma are described. Two patients, submitted to the therapeutic protocol established for endometrial carcinoma, underwent surgery, radiotherapy and chemotherapy for solitary cerebral metastasis after at average interval of 18 months. Average survival was 46 months and death was due to progression of the systemic disease. An examination of our cases and those described in the literature has shown that, although these metastasis do not respond well to therapeutic treatment, a better outcome may be achieved by combined treatment consisting of surgery, radiotherapy and chemotherapy.

Metastatic spinal cord compression. Clinical remarks

BACKGROUND

Metastatic compression of the spinal cord is a frequent occurrence throughout the evolution of neoplastic disease. Possible clinical-diagnostic strategies and therapeutic management of this pathology are discussed in terms of survival and quality of life.

METHODS

The study includes 59 patients (40 males and 19 females, with an average age of 48.4 years) with metastatic spinal compression treated surgically in our centre (in some cases with stabilization of the spinal segment involved).

RESULTS

In 40 cases the localization of the primary tumor was known when the patient was admitted. The segment involved was the dorsal one in 41 cases. The most frequent type of tumor was pulmonary carcinoma in males and breast carcinoma in females. Average survival was 5.3 months. Treatment integrated by stabilization improved the quality of life in comparison to laminectomy alone. Survival was also influenced by the histological type and site of the primary tumor.

CONCLUSIONS

Surgical treatment not only prolongs survival but, above-all, guarantees a satisfactory quality of life.

Long-term survival in a patient with supratentorial glioblastoma: clinical considerations

Glioblastoma, a malignant tumor of neuroepithelial origin, is relatively uncommon in childhood, during which it accounts for 7%-9% of brain tumors. A few patients (about 3%) live more than 5 years. We report a 13-year-old girl who was admitted because one month earlier she had begun to present headache and diplopia. Brain computed tomography (CT) showed a right frontal tumor. At operation, complete excision of the visible tumor was performed. Histologic examination showed that the tumor was a glioblastoma multiforme. The patient underwent 52 Gy of external beam radiotherapy to the enhancing tumor mass plus 3-cm border, and chemotherapy with nitrosourea (BCNU). Fourteen years, 9 months later, the patient presents neither neurological deficits nor radiological relapse. We confirm that younger age, the one immutable prognostic factor, supports a particularly aggressive approach to the treatment of glioblastomas.

Desmoplastic fibroma of the skull. Case report and review of the literature

BACKGROUND AND PURPOSE

We present a rare case of desmoplastic fibroma of the skull. Desmoplastic fibroma is a distinctive and rare neoplasm of bone that histologically and biologically mimics desmoid soft tissue tumor. Only 6 cases have been reported in the skull and none of these was diagnosed by MRI.

CLINICAL PRESENTATION

A 64 year-old woman, operated on in June 1991 for left mastectomy due to a ductal adenocarcinoma and again in October 1994 for a left frontal metastatic adenocarcinoma, was admitted in our Department of Neurosurgery because a control cerebral MRI had detected a diploic lesion, isointense on T1-weighted images and hyperintense on T2, with moderate enhancement, localized in a right parietal site. Neurological examination was negative. The lesion was surgically removed and a cranioplasty was performed. Histological diagnosis was desmoplastic fibroma. Twelve months after treatment she has no neurological symptoms or signs of cerebral lesions (MRI) or systemic metastasis (total body CT).

CONCLUSION

In the literature the number of desmoplastic fibroma is too small and the follow-up period too short to permit any conclusions regarding the aggressiveness of the tumor.

Epithelioid schwannoma of the ulnar nerve. Some clinical observations

The authors describe one case of purely epithelioid schwannoma of the ulnar nerve and discuss the therapeutic management. A 44 year-old man was referred to us for a fusiform, movable mass in the left ulnar nerve and was removed by a wide en bloc excision. Intraoperative nerve action potentials were performed both prior to and following excision of the lesion. Histologically, the tumor was composed of round or polygonal cells arranged in necrotic clusters and anastomosing cords. There were areas of spindle cells. The epithelioid cells were round with abundant cytoplasm. Mitoses were frequent. S100 protein immunoreactivity was present diffusely in tumor cells (both nuclear and cytoplasmic), whereas cytokeratin, NSE, and anti-melanoma reactions gave negative results. After a 13 months, the patient's neurological conditions are excellent and there are no signs of either recurrence or metastasis.

[Epidermoid cyst of the cranial vault. Neuroradiological and therapeutic considerations]

AIM

Intradiploic epidermoid cyst is a slow-growing tumor affecting only rarely the cranial bones.

PATIENT

The authors describe a case of intradiploic epidermoid cyst of the cranial vault in which there was a predominantly intracranial extension. Roentgenographic and CT findings do not permit a differential diagnosis. Complete removal of the cyst and its capsule was accomplished, with complete recovery.

CONCLUSION

Total removal oft the tumor and its capsule is associated with a very good long-term prognosis without recurrences.

Sarcoma metastatic to the brain: a series of 15 cases

METHODS

We report on 15 patients surgically treated for intraparenchymal brain metastases from sarcoma, including six osteosarcomas, five leiomyosarcomas, two malignant fibrous histiocytomas, and two alveolar soft-part sarcomas (ASPS).

RESULT

Median survival after craniotomy was 9.3 months. Patients with a preoperative Karnofsky performance score of > 70 survived for 12.8 versus 5.3 months for those with a Karnofsky performance score < 70 (p=0.03). Patients with evidence of only lung metastases at the time of surgery (nine cases) survived 8.6 months, which was similar to the 10.4-month survival for patients with disease limited to the brain (p=0.1). The two patients with alveolar soft-part sarcomas are alive at 15 and 20 months after surgery.

CONCLUSION

We conclude that surgery is effective in treating selected patients with sarcoma metastatic to the brain and that patients with metastasis from ASPS may have a relatively good prognosis if they are surgically treated. The complete removal of all brain metastases and a Karnofsky performance score > 70 are associated with a favorable prognosis; the presence of concurrent lung metastases is not a contraindication to surgery.

Role of the dimeric structure in Cu,Zn superoxide dismutase. pH-dependent, reversible denaturation of the monomeric enzyme from Escherichia coli

To investigate the structural/functional role of the dimeric structure in Cu,Zn superoxide dismutases, we have studied the stability to a variety of agents of the Escherichia coli enzyme, the only monomeric variant of this class so far isolated. Differential scanning calorimetry of the native enzyme showed the presence of two well defined peaks identified as the metal free and holoprotein. Unlike dimeric Cu,Zn superoxide dismutases, the unfolding of the monomeric enzyme was found to be highly reversible, a behavior that may be explained by the absence of free cysteines and the highly polar nature of its molecular surface. The melting temperature of the E. coli enzyme was found to be pH-dependent with the holoenzyme transition centered at 66 degrees C at pH 7.8 and at 79.3 degrees C at pH 6.0. The active-site metals, which were easily displaced from the active site by EDTA, were found to enhance the thermal stability of the monomeric apoprotein but to a lower extent than in the dimeric enzymes from eukaryotic sources. Apo-superoxide dismutase from E. coli was shown to be nearly as stable as the bovine apoenzyme, whose holo form is much more stable and less sensitive to pH variations. The remarkable pH susceptibility of the E. coli enzyme structure was paralleled by the slow decrease in activity of the enzyme incubated at alkaline pH and by modification of the EPR spectrum at lower pH values than in the case of dimeric enzymes. Unlike eukaryotic Cu,Zn superoxide dismutases, the active-site structure of the E. coli enzyme was shown to be reversibly perturbed by urea. These observations suggest that the conformational stability of Cu,Zn superoxide dismutases is largely due to the intrinsic stability of the beta-barrel fold rather than to the dimeric structure and that pH sensitivity and weak metal binding of the E. coli enzyme are due to higher flexibility and accessibility to the solvent of its active-site region.

Intracerebral schwannoma. Case report

A case of intraparenchymal schwannoma is presented. A 61-year-old woman, with stigmata of von Recklinghausen's neurofibromatosis (NF-2), presented with a history of weakness of the right lower limb for 2 months. She was investigated by MR which showed a circular mass with a maximum diameter of 5 cm in the right parieto-occipital lobe. The tumor was removed in toto via a left parieto-occipital craniotomy. The patient was discharged two weeks after the operation and remains well now 2 years later. The clinical and neuroradiological findings of reported intraparenchymal schwannomas, including the case reported here, are discussed.

Benign neural sheath tumours of major nerves: characteristics in 119 surgical cases

Peripheral benign nerve sheath tumours are infrequent tumours and affect major nerve trunks. Some authors have indicated a high and prohibitive incidence of neurological injury in resection of these lesions. The authors describe their findings in a retrospective study comprising 119 patients with spontaneous benign nerve sheath tumours of the peripheral nervous system. Seventy-three patients had a schwannoma, 41 had neurofibroma and 5 had plexiform neurofibroma; 25 of the 119 patients suffered from neurofibromatosis. All schwannomas were excised completely and the outcome of patients was 41.0% improved, 6.8% worsened, 52.0% unchanged. Twenty-eight neurofibromas were excised completely and 13 subtotally; the outcome for patients was 19.5% improved, 19.5% worsened and 61% unchanged. All plexiform neurofibromas were removed subtotally and the outcome for patients was 20% improved and 80% unchanged. The best surgical results at average follow-up of 6 years were observed in the patients with schwannoma, the worst in those with plexiform neurofibroma. Our results demonstrated that it is often possible to remove schwannomas as well as neurofibromas with an acceptable risk of injury to the nerve.

Primary rhabdomyosarcoma of the brain: observations on a case with clinical and radiological evidence of cure

Cerebral rhabdomyosarcoma is a highly aggressive tumor with poor prognosis affecting children and, rarely, adults. The authors describe the case of a patient treated for primary fronto-parietal embryonal rhabdomyosarcoma with a long survival (30 months after surgery) and no clinical or radiological evidence of recurrence and discuss the chemotherapy applied in this case.

Long-term survival in patients with supratentorial glioblastoma

The authors report 11 patients with cerebral glioblastoma who lived at least 5 years after their initial diagnosis. There were 6 female and 5 male; the mean age was 39 years (range 24-55 years). All patients were treated surgically and postoperatively received whole-brain radiotherapy and chemotherapy. Five patients (45%) presented local recurrences after an average interval of 3.9 years from treatment. At average follow-up of 9 years (range 5-14 years), 7 patients (64%) were alive after an average interval of 8.1 years; 4 patients (36%) died from local relapse. Survival was influenced by patient age and, to a lesser degree, by treatment. A review of the literature, together with our own series, suggest that death from recurrence disease is unusual in glioblastoma patients who survive more than 5 years.

Severe head trauma. Review of the factors influencing the prognosis

A series of 72 severely head injured patients are reported, 24 (33%) with surgical intracranial hematomas. All patients were intensively cared for under the same therapeutic regime; intracranial pressure (ICP) was monitored and treated if increased. The series mortality was 39%. Uncontrollable increase of ICP (UI-ICP), always fatal, was observed in 18% of patients and in 13 of 28 deaths (46%); the incidence of UI-ICP among deaths was higher in patients less than in those more than 40 years old (55% vs 25%). Patients with UI-ICP were frequently deeply comatose and with arterial hypotension on admission; almost all died in the first days. Patients directly admitted from the scene with well staffed Life Flight Helicopter Emergency Care compared with those directly admitted from the scene with different type of ambulance service (paramedics, police, firemen and private) had a mortality rate significantly less (20% vs 54%) and an incidence of UI-ICP strongly lower both among patients (5% vs 29%) and among deaths (25% vs 54%). Thus in this small series intensive care after admission was not effective to obtain good results if patients had received poor preadmission emergency care. Review of the literature on main clinical predictors of outcome in severe head injury, have made possible some observations. Ischemic and intracranial hypertension brain lesions were generally present in patients killed by head trauma; while diffuse axonal injury, frequently responsible for vegetative, severe disability survival and late deaths, was observed only in 20-30% of postmortem examinations. Old age, poor neurological status and cardiocirculatory and respiratory disturbances prior to and upon admission positively worsened the outcome, while intracranial hematomas had a more variable predictive value. Intracranial hypertension was a definitively ominous predictor only if very high when the risk to be or become uncontrollable seems to be much elevated. UI-ICP, often fatal despite any aggressive therapy, was the single most frequent killer after severe head injury, responsible for about half of all deaths after admission. The different outcome among severe head injury series could be conceivably related to a different frequency of UI-ICP. Besides the severity of head injury and delay and mode of admission, we suggest that preadmission respiratory and cardiocirculatory and the quality of emergency medical system could strongly affect the incidence of uncontrollable increase of ICP in admitted patients and thus the mortality rate and favorable recovery of the series. The advanced preadmission emergency care service with intensive care after admission could significantly explain the better results often observed in severe head injury series.

Spontaneous movement of metallic foreign bodies. Case report

We report a case of missile injury to the brain with an unusual complication. The bullet migrated by its mere weight to a distant location through the brain parenchyma after initially lodged in a superficial site. Movement of the bullet was first detected on CT scan and the significance and treatment of this finding is emphasized.

Glycosylation of RNA polymerase II from wheat germ

RNA polymerase II from wheat germ was analyzed for the presence of sugars. The two largest subunits and the 27 and 25 kDa subunits were found to be glycosylated by a variety of sugars. However, no N-acetylglucosamine was detected, which was found by Kelly et al. (J. Biol. Chem. (1993) 268, 10416-10424) in the largest subunit of RNA polymerase II from calf thymus. Thus it appears that the regulatory function of this sugar, postulated by Kelly et al., is performed in the wheat germ enzyme by other monosaccharides. Carbohydrate analysis of the two largest subunits of the calf thymus enzyme also revealed the presence, beside N-acetylglucosamine, of other sugars. Some similarities in the features of glycosylation of the two polymerases, isolated from very different organisms, suggest that the sugar moieties have an important role in the structure and/or function of these enzymes.

Recurrence from filum terminale ependymoma 42 years after 'total' removal and radiotherapy

The authors describe the unusual case of a patient requiring reoperation for ependymoma of the filum terminale after a symptom-free period of 42 years: treatment of the primary tumor consisted of macroscopically complete surgical excision and postoperative radiotherapy. This case brings to light some interesting observations: a late recurrence, as in the case reported here, appears to be rare especially if the tumor presents in adult age; the long preoperative clinical history (26 months) and the initial aspect of the tumor that infiltrated 2 caudal roots, removed together with the tumor, may have been factors correlated with the risk of recurrence: postoperative radiotherapy may have helped to delay clinical manifestation of the recurrence. Ependymomas of the filum terminale may clinically recur even after complete removal. The latest clinical recurrence described in the literature occurred after 26 years.

Solitary cerebral metastasis from tumor of the testis: some observations about treatment in two cases

The authors describe two cases of solitary cerebral metastasis from non-seminatous germ cell tumors of the testis: in the first case, the histology was teratocarcinoma; in the second, it was embryonal carcinoma. Both patients underwent surgery, whole-brain radiotherapy and chemotherapy, and are still alive and disease-free after respectively 42 and 72 months. Although systemic metastasis from tumors of the testis are relatively common, they rarely involve the nervous system. A review of our cases and those reported in the literature shows that the outcome in these patients can be improved by the combined surgical, radiological and chemotherapeutic treatment of the metastasis.

Dural tail in pituitary adenoma

Although a dural tail has been described in association with meningiomas and, rarely, with other tumors in MR imaging with Gd-DPTA. Recently, a pituitary lesion was evaluated by MRI and presented a tail. For this reason the lesion was thought to be a meningioma of the tuberculum sellae, but at surgery proved to be an adenoma.

Long-term prognosis for atypical and malignant meningiomas: a study of 71 surgical cases

To contribute to a better understanding of the prognostic differences between atypical and malignant meningiomas as defined by the World Health Organization (WHO) and the influence of the grade of initial surgical excision on postoperative course, 42 cases of atypical and 29 of malignant meningioma were studied, along with long-term follow up. The two groups were compared with respect to long-term survival, recurrence-free survival, and median time to recurrence. The prognostic significance of the Simpson grade of surgical resection and tumor location was also considered. Survival at 5 and 10 years was recorded in 95% and 79%, respectively, of patients with atypical meningioma and in 64.3% and 34.5% of patients with malignant meningioma (p = 0.001). Recurrence-free survival and median time to recurrence were also significantly longer in patients with atypical than in those with malignant meningiomas: 11.9 versus 2 years (p = 0.001) and 5 versus 2 years (p < 0.0041), respectively. Six (26%) of the 23 recurring atypical meningiomas became malignant. Simpson Grade I resection and location in the cerebral convexity, which were closely related, were found to be associated with a significantly better clinical course in the entire series (p < or = 0.0016). Patients with atypical meningiomas fared better than those with malignant meningiomas after incomplete surgical excision (Simpson Grades II-III), but the difference was not statistically significant. Multivariate analysis using the Cox model indicated that radical extirpation (Simpson Grade I vs. II-III) and histological findings (atypical meningioma vs. malignant meningioma) were significantly related to prolonged survival (p < 0.0003 and p < 0.0388, respectively). In conclusion, the current study shows that for most patients with atypical meningioma the prognosis was less severe than for those with malignant meningioma, but the risk of a downhill course resulting from malignancy after incomplete resection and recurrence was not negligible (26%). In addition, the WHO classification was found to be inadequate for a minority of the atypical meningioma cases, which currently have the same unfavorable course as cases of malignant meningioma. The results also indicate that objective Simpson Grade I extirpation of convexity meningiomas can be successful despite histological findings of malignancy.

High-dose radiation-induced meningiomas

BACKGROUND

Numerous neoplasms within the CNS have been reported as radiogenic in origin; radiation-induced meningiomas are at least five times more numerous than gliomas or sarcomas in the world literature.

METHODS

The authors review 10 cases of cerebral meningiomas following high-dose radiotherapy in patients operated for neoplasm of the nervous system. The pathologic and clinical aspects of this unusual complication are analyzed in all cases in the world literature.

RESULTS

There is a female predominance (F-M ratio: 3:2) and the patients are young (mean age: 33.1 years; median: 29 years). The average latency period is 14.4 years (range: 9-21 years). The first disease is acute lymphocytic leukemia (ALL) in 40% of cases. Radiation induced meningiomas are atypical in four cases. Recurrence was observed in one case without malignant transformation.

CONCLUSION

High-dose radiation-induced meningiomas have the following characteristics: (1) children appear particularly sensitive to the development of this tumor; (2) there is a female predominance, otherwise than is observed in low-dose meningioma; (3) these tumors present a peak frequency in the third decade of life; and (4) frequently, these tumors are atypical and recur. Finally, it is essential that every new case be reported to throw light on this particular pathologic correlation with its many grey areas.

[Neurinomas and ependymomas of the cauda equina. A review of the clinical characteristics]

A retrospective review of 603 cases of intradural benign tumors of the cauda equina are presented (283 schwannomas and 320 ependymomas). For each tumor, the clinical course and long-term postoperative results were analyzed: it emerged that differential diagnosis between neurinomas and non tumoral lesions is not possible if based on clinical findings alone and that neuroradiological diagnosis is more accurate when MRI is employed. Long-term prognosis of neurinomas was always favourable, while in the ependymomas, early diagnosis gives excellent results because prognosis is apparently directly correlated to the length of preoperative clinical history.

[Intramedullary cervical neurinoma. A case report and review of the literature]

A case of intramedullary neurinoma of the cervical spinal cord in a patient with no sign of von Recklinghausen's disease is reported. It was diagnosed by computed tomography and magnetic resonance imaging and treated surgically. Discussion examines etiology, role of diagnostic procedures and surgical treatment of this rare tumor.

Long-term prognosis for atypical and malignant meningiomas: a study of 71 surgical cases

To contribute to a better understanding of the prognostic differences between atypical and malignant meningiomas as defined by the World Health Organization (WHO) and the influence of the grade of initial surgical excision on postoperative course, 42 cases of atypical and 29 of malignant meningioma were studied, along with long-term follow up. The two groups were compared with respect to long-term survival, recurrence-free survival, and median time to recurrence. The prognostic significance of the Simpson grade of surgical resection and tumor location was also considered. Survival at 5 and 10 years was recorded in 95% and 79%, respectively, of patients with atypical meningioma and in 64.3% and 34.5% of patients with malignant meningioma (p = 0.001). Recurrence-free survival and median time to recurrence were also significantly longer in patients with atypical than in those with malignant meningiomas: 11.9 versus 2 years (p = 0.001) and 5 versus 2 years (p < 0.0041), respectively. Six (26%) of the 23 recurring atypical meningiomas became malignant. Simpson Grade I resection and location in the cerebral convexity, which were closely related, were found to be associated with a significantly better clinical course in the entire series (p ¾ 0.0016). Patients with atypical meningiomas fared better than those with malignant meningiomas after incomplete surgical excision (Simpson Grades II-III), but the difference was not statistically significant. Multivariate analysis using the Cox model indicated that radical extirpation (Simpson Grade I vs. II-III) and histological findings (atypical meningioma vs. malignant meningioma) were significantly related to prolonged survival (p < 0.0003 and p < 0.0388, respectively). In conclusion, the current study shows that for most patients with atypical meningioma the prognosis was less severe than for those with malignant meningioma, but the risk of a downhill course resulting from malignancy after incomplete resection and recurrence was not negligible (26%). In addition, the WHO classification was found to be inadequate for a minority of the atypical meningioma cases, which currently have the same unfavorable course as cases of malignant meningioma. The results also indicate that objective Simpson Grade I extirpation of convexity meningiomas can be successful despite histological findings of malignancy.

Radiation-induced sarcoma of the skull: report of two cases

The authors describe two cases of sarcomas of the skull following cranial irradiation in patients treated for other neoplasms, acute lymphatic leukemia, and astrocytoma, respectively. The patients (one man and one woman: mean age 24.5 years) developed sarcomas within the irradiated field after a mean latency period of 11.5 years. Histologically, the tumor proved to be a fibrosarcoma. Despite aggressive surgery and other therapy, the survival of the patients was short (10 and 8 months, respectively). The pathological and clinical aspects of this unusual complication are analyzed with reference to 41 cases taken from the world literature.

Rathke's cleft cyst: a clinical and radiographic review

We report the case of a 62-year-old woman, who had a 4-year history of progressive visual acuity deficit. On neurological examination, visual acuity was 5/20 in the right and 4/20 in the left eye. A hormonal study revealed hypophyseal hypofunction. CT and MRI scans showed an intra-suprasellar cystic lesion, hyperintense in T1 and hyperintense in T2-weighted sequences. At surgery, the cyst wall was opened and the cavity placed in communication with the subarachnoid space. Histological examination showed a Rathke's cleft cyst. After four years of follow-up the patient's visual deficit remained unchanged, whereas the results of the hormonal assays were normal. An MRI scan confirmed the absence of the cyst. We review 216 reported cases of Rathke's cyst and discuss its pathogenesis, clinical features and treatment.

Multicentric and multifocal primary cerebral tumours. Methods of diagnosis and treatment

Forty patients with multifocal and multicentric cerebral tumours were retrospectively studied. The patients were divided into two groups: ten patients with multicentric tumours (group A), and 30 patients with multifocal tumours. As far as their preoperative clinical history and the incidence of the various symptoms and signs are concerned, there were no significant differences between the two groups. CT permitted a correct diagnosis in 90% of the cases. All of the patients underwent the removal of the tumour(s) and received radiotherapy; 30 patients also received chemotherapy. In group A, nine patients died and one was lost to follow-up one year after treatment; the average survival was ten months from the appearance of the multicentric tumour. In group B, 29 patients died and one is still alive two years after treatment; the average survival was six months. We consider the problems of diagnosis and the long-term follow-up of patients.

Prognostic factors in intramedullary astrocytomas

This report presents a retrospective prognostic study of 65 patients with intramedullary astrocytoma surgically treated between 1953 and 1990. Median survival and statistical survival at 5 years were assessed in relation to clinical, histological and therapeutic factors for each patient. Results showed that factors positively influencing the prognosis are low histological grade of the tumour and good pre- and post-operative general conditions. Among the grade II astrocytomas, the fibrillary and protoplasmatic types presented longer survival times regardless of the type of removal performed. In anaplastic astrocytomas the simultaneous presence of certain morphological features indicative of higher malignancy negatively influenced survival. The degree of resection did not influence average survival within each histological grade.

Synovial cysts: clinical and neuroradiological aspects

Lumbar and intraneural synovial cysts are uncommon lesions, although their incidence has increased since the introduction of MRI. The authors describe the results of a study comprising 23 patients with synovial cyst (5 lumbar, 19 intraneural). Neuroradiological investigations included CT scan and MRI; however, it was not always possible to diagnose the nature of the lesion. In 18 cases the lesion was removed totally including its capsule; in the other 5 cases it was removed subtotally. Seven of the 23 patients presented a total remission of symptoms/signs, 11 improved and 5 remained unchanged. The importance of treating synovial cysts as radically as possible is discussed together with their most significant clinical and neuroradiological aspects.

Primary spinal epidural non-Hodgkin's lymphomas in childhood: a review of 6 cases

We report a retrospective study regarding 6 children with primary epidural non-Hodgkin's lymphomas and analyse the factors influencing prognosis with emphasis on treatment. Four patients were females and 2 males. The neurological condition of patients was assessed pre- and postoperatively according to Shaw's classification for neurological disability. All patients were submitted to surgery, radiotherapy and chemotherapy. Histologically, the tumour proved to be a high-grade non-Hodgkin's lymphoma in all cases. At follow-up, all patients are alive after a median interval of 52 months (range 24-72 months). This study showed that the outcome of patients depends on the gravity of pre-operative deficits whereas the survival is influenced by the type of treatment.

Central neurocytoma: clinical features of 8 cases

The authors report 8 cases of central neurocytoma with a minimum follow-up of 3 years. Five patients were males and 3 females with average age of 21 years. All patients underwent surgical removal of tumor, and radiotherapy was delivered to 2 of the 3 patients in whom removal had been partial. At an average follow-up of 5 years, all patients are alive and none of them has presented signs of recurrence or progression of the disease. Some typical clinical and histological features of this tumor are pointed out.