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Biomedical subjects

C H Rickert

Publications and source records attributed to C H Rickert.

At least 19 recordsLinked to original sources

Lack of chromosomal imbalances in adamantinomatous and papillary craniopharyngiomas.

Craniopharyngiomas are among the most common paediatric tumours and are thought to arise from embryonic remnants of Rathke's pouch. The molecular mechanisms involved in their formation remain elusive and little is known about chromosomal imbalances that could suggest the locations of tumour suppressor or proto-oncogenes involved in the pathogenesis. The paucity of published data on the molecular basis of such tumours prompted this investigation of 20 adamantinomatous and nine papillary craniopharyngiomas for genetic abnormalities by comparative genomic hybridisation (CGH). CGH revealed no DNA copy number changes in any of the 29 primary craniopharyngiomas, regardless of their histological subtype. These data suggest that chromosomal imbalances are a rare event in both adamantinomatous and papillary craniopharyngiomas.

Adolescent↗

Immunoglobulin deposition in sural nerves of AIDS patients with distal-symmetric HIV-associated polyneuropathy.

The most frequent neurological diagnosis in peripheral nerve function of HIV-positive individuals is distal-symmetric polyneuropathy (DSPN). In this study we investigated the histopathology as well as the immunohistochemical expression of immunoglobulins IgA, IgG and IgM in post-mortem sural nerve tissue gained from 11 patients who had suffered from DSPN in the clinical course of AIDS (CDC 3C). We found that all 11 sural nerves showed signs of demyelination while in 6 out of 11 cases axonal degeneration could also be detected. Immunohistochemical expression of at least one immunoglobulin was found in all but two cases with deposits uniformly being located immediately beneath the basement membrane of capillary blood vessels and within the perineurium while endoneurial staining was discernable in three cases. The most commonly expressed immunoglobulin was IgA which was identified in 7 cases, followed by IgG and IgM which were positive in 6 and 5 cases, respectively. All three immunoglobulins were found to be expressed simultaneously in only two cases. Thus, our study shows that immunoglobulin deposits among other factors may be implicated in altering the function of sural nerves or enhance their vulnerability. In peripheral nerves they may be responsible for some of the common alterations in the development of AIDS-associated distal symmetric polyneuropathy.

Acquired Immunodeficiency Syndrome↗

Mycotic cerebral vasculitis in a paediatric cardiac transplant patient excludes misadventure.

We present the case of a 10-year-old girl with cardiomyopathy who received a heart transplant. Due to organ rejection, the dosage of immunosuppressive agents was increased postoperatively. The patient complained of intermittent headaches in the following days and developed a haemorrhagic necrosis of the left thalamus. A week later, an oral dose of cyclosporin A was accidentally given intravenously, and 2 weeks later a recurrent subarachnoid haemorrhage of unknown origin was diagnosed. The clinical course was then characterised by progressive deterioration resulting in coma, fluctuating brain stem symptoms and the development of a massive cerebral oedema with subsequent brain death. A coroner's autopsy was instigated to investigate a claim of medical misadventure. Neuropathological investigations found a focal infiltration of fungal hyphae in the left posterior cerebral artery resulting in necrosis of the vascular wall and thus explaining the source of the recurrent subarachnoid haemorrhage which eventually resulted in the girl's death. Medical misadventure due to the administration of cyclosporin was not directly responsible for the death of this patient. This case illustrates that it is of paramount importance to copiously sample and investigate the basal cerebral arteries in cases of subarachnoid haemorrhage of unknown origin, in particular in a medico-legal context.

Aspergillosis↗

Population-based epidemiologic data on brain tumors in German children.

BACKGROUND: Brain tumors are the most common disease group of solid tumors in childhood, and children with brain tumors have a relatively poor survival rate. Epidemiologic data from a population-based cancer registry provide the necessary information to obtain a full picture of the frequency of this disease, which is a great challenge in pediatric oncology. METHODS: The German Childhood Cancer Registry (GCCR) is a population-based registry. The level of completeness of patient registration is 95%, but it is somewhat lower for patients with brain tumors. More than 300 children with newly diagnosed brain tumors are reported every year. Analyses of GCCR data are performed according to the International Classification of Childhood Cancer and the recently published World Health Organization classification of tumors of the nervous system. In addition, incidence rates of childhood brain tumors in Germany are compared with those of other countries, as published by the International Agency for Research on Cancer. RESULTS: In the years 1990-1999, a total of 3268 brain tumors were observed (excluding intracranial and intraspinal germ cell tumors). The respective incidence rate for children age < 15 years was 2.6 per 100,000 children and lies between the rates from other countries, which range between 1.7 and 4.1 per 100,000 children. The most common brain tumors were astrocytomas (41.7%), medulloblastomas (18.1%), ependymomas (10.4%), supratentorial primative neuroectodermal tumors (PNETs; 6.7%), and craniopharyngiomas (4.4%). They were located mainly in the cerebellum (27.9%) and the cerebrum (21.2%). The 5-year survival rate for all brain tumors was 64%, with the poorest prognosis for children with PNET. CONCLUSIONS: The large data base of the GCCR made it possible to present representative data on patients with childhood tumors of the central nervous system in Germany. The data quality was high, not least because of the strong cooperation with corresponding clinical trials. However, for children with central nervous system tumors, the ascertainment of newly diagnosed patients needs further improvement.

Adolescent↗

Tumors of the choroid plexus.

Choroid plexus tumors are rare intraventricular papillary neoplasms derived from choroid plexus epithelium, which account for only between 0.4-0.6% of all intracranial and 2-3% of pediatric neoplasms. Plexus papillomas outnumber choroid plexus carcinomas by a ratio of 5:1 and around 80% of choroid plexus carcinomas arise in children. Plexus tumors are most common in the lateral and fourth ventricles; while 80% of lateral ventricle tumors present in children, fourth ventricle tumors are evenly distributed in all age groups. Clinically, choroid plexus tumors tend to cause hydrocephalus and increased intracranial pressure. Histologically, choroid plexus papillomas correspond to WHO grade I, choroid plexus carcinomas to WHO grade III. Immunohistochemically, cytokeratins and vimentin are expressed by virtually all choroid plexus papillomas and most choroid plexus carcinomas while transthyretin and S-100 protein are present in 80-90% of cases, less frequently, though, in choroid plexus carcinomas. Glial fibrillary acidic protein can be found focally in about 25-55% of choroid plexus papillomas and 20% of choroid plexus carcinomas. The mean Ki67/MIB1 labeling index for choroid plexus papillomas is 1.9%, for choroid plexus carcinomas 13. 8%. Choroid plexus papillomas typically show hyperdiploidy with gains particularly on chromosomes 7, 9, 12, 15, 17, and 18 while one choroid plexus carcinoma showed rearrangements of chromosomes 7p11-12, 9q11-12, 15q22, and 19q13.4. Choroid plexus papillomas can usually be cured by surgery alone with a 5-year survival rate of up to 100% with occasional recurrences while choroid plexus carcinomas grow more rapidly and have a less favorable outcome with a 5-year survival rate of 26-40%.

Animals↗

Comparative genomic hybridization in pineal parenchymal tumors.

Nine pineal parenchymal tumors were studied by comparative genomic hybridization. These consisted of three pineocytomas (WHO grade II), three pineal parenchymal tumors of intermediate differentiation (WHO grade III), and three pineoblastomas (WHO grade IV). An average of 0 chromosomal changes per pineocytoma, 5.3 per pineal parenchymal tumor of intermediate differentiation (3.3 gains vs. 2.0 losses), and 5.6 per pineoblastoma (2.3 gains vs. 3.3 losses) were found. The most frequent DNA copy number changes among pineal parenchymal tumors of intermediate differentiation and pineoblastomas were gains of 12q (3/6 cases), 4q, 5p, and 5q (2/6 cases each), as well as losses of 22 (4/6 cases), 9q, and 16q (2/6 cases each). Among pineal parenchymal tumors of intermediate differentiation, the most common chromosomal imbalances were +4q, +12q, and -22 (2/3 cases each), and in pineoblastomas -22 (2/3 cases). Five high level gains were identified, all of them in pineoblastomas; these were found on 1q12-qter, 5p13.2-14, 5q21-qter, 6p12-pter, and 14q21-qter. Clinically, all patients with pineocytomas and pineal parenchymal tumors of intermediate differentiation were alive after a mean observation time of 142 and 55 months, respectively, whereas all patients with pineoblastomas had died after an average of 17 months. Our findings suggest that pineal parenchymal tumors of intermediate differentiation are cytogenetically more similar to pineoblastomas and prognostically more similar to pineocytomas. Furthermore, imbalances in higher-grade pineal parenchymal tumors mainly affect gains of 12q and losses of chromosome 22.

Adult↗

[Primary central nervous system lymphoma as a neurological manifestation of AIDS stage].

In patients infected with human immunodeficiency virus (HIV), the risk of developing non-Hodgkin's lymphoma is over 100 times greater than with noninfected persons. Primary central nervous system lymphoma as a complication of the acquired immunodeficiency syndrome (AIDS) occurs in up to 2.4% of all cases and is strongly associated with the Epstein-Barr virus. The prognosis is very poor, with a mean survival time of 21 to 27 days without therapy and up to 119 days with radiation therapy. We describe the course of seven AIDS patients with histologically proven primary central nervous system lymphoma and present a review of clinical symptoms, diagnosis, and therapy. The main criteria for differential diagnosis from other secondary neuromanifestations such as cerebral toxoplasmosis, progressive multifocal leukoencephalopathy, abscesses, and infarctions are described.

AIDS-Related Opportunistic Infections↗

High uptake of L-3-[123I]iodo-alpha-methyl tyrosine in pilocytic astrocytomas.

Despite a favourable prognosis, pilocytic astrocytomas may exhibit signs of malignancy on various neuroimaging modalities. This retrospective analysis was conducted to determine whether scintigraphic features of malignancy are also found on single-photon emission tomography (SPET) using L-3-[123I]iodo-alpha-methyl tyrosine (IMT) as a tracer. Twenty patients with pilocytic astrocytomas were retrospectively selected from a large series of patients referred for the evaluation of primary or recurrent brain tumours. IMT SPET was performed in 16 patients, positron emission tomography (PET) using 2-[18F]fluoro-2-deoxy-D-glucose (FDG) was available in 10 of the patients and SPET using technetium-99m tetrofosmin or thallium-201 had been performed in 11. Image analysis was performed using standard protocols to determine how many patients exceeded the respective thresholds of malignancy. Features of malignancy were found in 7/16 IMT SPET studies, in 7/10 FDG PET studies and in 7/11 of the residual SPET investigations. A significant correlation of tumour size and IMT uptake in primary pilocytic astrocytomas indicated partial volume effects to partly account for the differential uptake behaviour (n = 10, r = 0.87, P < 0.05). Differences in IMT uptake in primaries (1.7 +/- 0.6, n = 10) and in recurrent tumours (2.3 +/- 0.7, n = 6) did not attain statistical significance. IMT SPET results indicative of malignancy are regularly found in pilocytic astrocytomas, despite their good prognosis. No uptake may be detected in largely cystic or in small tumours.

Adolescent↗

Epidemiology of central nervous system tumors in childhood and adolescence based on the new WHO classification.

METHOD: The topography, sex distribution and histology of 340 primary CNS tumors in children up to 17 years of age were investigated and (re-)classified according to the latest WHO classification of nervous system tumors. RESULTS: Overall the prevalence for boys (60.9%) was higher and supratentorial locations predominated (53.3%); there was an even distribution of low-grade WHO I/II (51.5%) and high-grade WHO III/IV (48.5%) tumors. Boys were more commonly affected in all age groups throughout childhood and adolescence. Infratentorial location was more common between the ages of 3 and 11 years (57.5%). High-grade tumors were more frequently encountered up to the age of 5 years (53.2%). The main histological entities were pilocytic astrocytomas (23.5%), followed by medulloblastomas (16.3%), ependymomas (10.1%), anaplastic astrocytomas and glioblastomas (7.2% each), and craniopharyngiomas (5.6%); astrocytomas overall accounted for 47.3% of pediatric brain tumors. Rarer entities included germ cell tumors, gangliogliomas, and meningiomas (2.5% each), supratentorial PNET and pineal parenchymal tumors (1.9% each), atypical teratoid/rhabdoid tumors (1.3%), choroid plexus tumors (0.9%), and desmoplastic infantile astrocytomas and dysembryoplastic neuroepithelial tumors (0.6% each). A meta-analysis of 10,582 childhood brain tumors accumulated from 16 international surveys revealed a male-female ratio of 1.29 and a supra-/infratentorial ratio of 0.92. The most common histological diagnoses were astrocytomas (37.6%), medulloblastomas (17.7%), ependymomas (9.9%), craniopharyngiomas (7.3%), and germ cell tumors (4.4%). CONCLUSIONS: Pediatric brain tumors vary considerably in their histological, topographical and gender distribution throughout childhood and adolescence, reflecting different dynamics of individual tumor entities as well as a susceptibility to their occurrence during certain periods of a child's life. Although at times difficult to characterize, pediatric CNS tumors can be satisfactorily classified according to the latest WHO classification of nervous system tumors.

Adolescent↗

Rosetted glioneuronal tumor: a case with proliferating neuronal nodules.

Glioneuronal tumors with neuropil-like islands (rosetted glioneuronal tumors) were recently reported as a novel brain tumor entity with characteristic clinicopathological features (Am J Surg Pathol 23: 502, 1999). Here we describe the clinical, histological and genetic features of another case arising in the parietal lobe of a 43-year-old man suffering from focal motor epilepsy. Histologically, nodules of small neuronal tumor cells immunoreactive for synaptophysin and NeuN were embedded within a diffuse astrocytoma. Remarkably, highest proliferative activity was observed within the neuronal nodules. Comparative genomic hybridization revealed a gain of chromosome 7q and a loss on chromosome 9p.

Adult↗

Increased chromosomal imbalances in recurrent pituitary adenomas.

Eight pituitary adenomas (four gonadotroph cell adenomas, three prolactin cell adenomas, one null cell adenoma) and their respective recurrences in the same patients were studied by comparative genomic hybridization. Chromosomal imbalances were found in seven of eight patients affecting two of eight primary and seven of eight recurrent tumors. Overall, pituitary adenomas showed an average of 1.6 chromosomal imbalances per primary and 3.4 per recurrent tumor (P < 0.01). Prolactin cell adenomas showed an average of 4.3 chromosomal changes per primary and 6.3 per recurrent tumor, which were significantly more common than in gonadotroph cell adenomas (0 vs 1.7 changes; P < 0.05) and the null cell adenoma (0 vs 1.0 changes; P < 0.05). The most common changes were gains of 4q (in three of eight recurrences), 5q, and 13q (in two of eight recurrences each) as well as losses of chromosome 2 (in both primary and recurring tumors of two patients), 1p, 8q, 10, and 12q (in two of eight recurrences). Minimal common regions associated with recurrent adenomas were gains of 4q31.2-34 (three recurrences), 5q14-23 and 13q21-31 and losses of 12q24.3-qter (two recurrences each). The average MIB-1 proliferation indices were 1.2% for primary and 1.9% for recurrent adenomas (P < 0.005). Our findings suggest that acquisition of certain chromosomal imbalances is related to and may underlie adenoma recurrence.

Adult↗

Chromosomal aberrations in pituitary carcinoma metastases.

Four pituitary carcinoma metastases [two adrenocorticotropic hormone (ACTH) and prolactin cell tumors each] were studied by comparative genomic hybridization. Chromosomal gains were found in all four carcinoma metastases, but losses only in the two prolactin cell carcinoma metastases. Overall, pituitary carcinoma metastases showed an average of 8.3 chromosomal imbalances per tumor (7 gains vs 1.3 losses), 10 in prolactin cell carcinoma metastases (7.5 gains vs 2.5 losses) and 6.5 in ACTH cell carcinoma metastases (6.5 gains vs 0 loss). The most common changes were gains of chromosome 5, 7p, and 14q (in three tumors each). High-level gains were found on 13q22-qter and 14q (two cases each) and on 1q, 3p, 7, 8, 9p, and 21q (one case each). To date, gains of chromosome 14q have not been reported among pituitary tumors. It remains to be shown whether gain of 14q is associated with malignant progression and metastatic dissemination of pituitary carcinomas.

ACTH Syndrome, Ectopic↗

Sudden unexpected death in young adults with chronic hydrocephalus.

We present four cases of sudden unexpected death in young adults with chronic hydrocephalus. The patients were between 20 and 28 years of age and had suffered from aqueduct stenosis (two patients), spina bifida in combination with Arnold-Chiari malformation (type II) and fragile X-syndrome. The patients suddenly collapsed with cardiorespiratory failure and could not be resuscitated and none had a history of headache or seizures. The post-mortem examinations revealed no unusual findings and a definite cause of death could not be established. Neuropathological examination revealed chronically hydrocephalic brains without any signs of uncal or tonsillar herniation. We hypothesise that a sudden pressure-induced decompensation of cerebral neuronal pathways involving insular and limbic cortex, hypothalamus and brain stem nuclei, may have caused disturbances of the cardiopulmonary control centres in the reticular formation of the brain stem, which in turn may have led to instantaneous cardiorespiratory arrest resulting in sudden "neurogenic" cardiac death.

Adult↗

Neglect-associated fatal Marchiafava-Bignami disease in a non-alcoholic woman.

We present the case of an 80-year-old malnourished and non-alcoholic woman who died from neglect-associated Marchiafava-Bignami disease, an illness usually almost exclusively occurring in male alcoholics. The patient had been bedridden for several months and had been looked after by her son. The patient was admitted to hospital in an extremely poor care condition suffering from severe exsiccosis, pressure sores and marasmus and died shortly afterwards. The initial post-mortem examination could not establish a definite cause of death, however, upon neuropathological examination a necrotising cystic lesion in the left cingulate gyrus as well as a central necrosis in the corpus callosum indicative of Marchiafava-Bignami disease were revealed. This is the first known case of Marchiafava-Bignami disease in a non-alcoholic woman and the first case in the forensic setting of neglect.

Aged↗

Pediatric high-grade astrocytomas show chromosomal imbalances distinct from adult cases.

We studied 23 pediatric high-grade astrocytomas by comparative genomic hybridization. Chromosomal imbalances were found in 10 of 10 anaplastic astrocytomas and 11 of 13 glioblastomas and consisted of +1q (43%), +3q (26%), +1p, +2q, +5q (22%), -22q (34%), -6q, -10q (30%), -9q, -11q, -13q, -16q, and -17p (22%). Anaplastic astrocytomas frequently showed +5q (40%), +1q (30%), -22q (50%), -6q, -9q (40%), and -12q (30%); glioblastomas +1q (54%), +3q (38%), +2q, +17q (23%), -6q, -8q, -10q, -13q, and -17p (31%). Minimal common regions mapped to +1q21-41, +3q27-qter, +2q31-32, +5q14-22, -22q12-qter, -10q23-25, -6q25-qter, -9q34.2, -11q14-22, -16q22-qter, and -17p. High-level gains were located on 1q (7 cases), 2q, 7q (4 cases), 3q (3 cases), 9, 17q (2 cases), 4q, 8q, 18, and 20q (1 case). A significantly shorter survival was found for anaplastic astrocytomas showing +1q (P: < 0.05), MIB-1 proliferation index >25% (P: < 0.001) and glioblastomas (P: < 0.05). Compared with adult cases, +1p, +2q, and +21q as well as -6q, -11q, and -16q were more frequent in pediatric malignant astrocytomas. Among the latter +5q, -6q, -9q, -12q, and -22q were characteristic for pediatric anaplastic astrocytomas and +1q, +3q, +16p, -8q, and -17p for pediatric glioblastomas. Our results show that chromosomal aberrations differ between pediatric anaplastic astrocytomas and glioblastomas as well as between pediatric and adult high-grade astrocytomas, supporting the notion of a different genetic pathway. Furthermore, gains of chromosomal material on 1q might be correlated with a worse prognosis in pediatric anaplastic astrocytomas.

Adolescent↗

[Progressive multifocal leukoencephalopathy in AIDS. Overview and retrospective analysis of 17 patients].

We describe retrospectively the course of 17 AIDS patients with progressive multifocal leukoencephalopathy (PML) and give a review of their clinical symptoms and survival times. The relative frequency of PML in our cohort of AIDS patients was 2.6%. The mean of CD4-positive cells was 80.5 +/- 82.5/microliter. CD4-positive cells were > 200/microliter only in one patient and increased significantly under a combination of three antiretroviral drugs whereas, with the other patients, CD4-positive cells did not increase with a maximum of two antiretroviral drugs. The mean survival time was 6.6 (1.5-20) months and correlated positively with the number of CD4-positive cells. The diagnosis of PML can be regarded as confirmed when JC-virus DNA is detectable in cerebrospinal fluid, typical changes can be seen in MRI and typical clinical symptoms occur. No effective therapy is known to date. Single case reports on therapy with cidofovir, as in one of the cases described here, showed positive results.

AIDS-Related Opportunistic Infections↗

Cerebral malakoplakia associated with Escherichia coli infection.

Malakoplakia is an unusual chronic inflammatory disease occurring predominantly in the bladder and only rarely affecting other organs. For the urinary tract, its aetiology has been ascribed to the presence of Escherichia coli, while the very few cases of cerebral malakoplakia which have been reported so far, have mostly occurred in infants in the clinical setting of neonatal herpes virus infection or otherwise in adults in areas of cerebral infarction. We here report a case of E. coli-associated malakoplakia of the brain. It occurred in a 53-year-old man who had undergone long-term corticosteroid therapy and had previously been operated on a cerebral E. coli-associated abscess. This case indicates that malakoplakia of the brain might also be a histiocytic reaction against bacterial antigens of the E. coli family.

Abscess↗

Comparative genomic hybridization in pineal germ cell tumors.

Fifteen primary pineal germ cell tumors (8 germinomas, 4 mixed teratomas-germinomas, 2 immature teratomas, and 1 yolk sac tumor) and 2 recurrences of the yolk sac tumor were studied by comparative genomic hybridization (CGH). An average of 1.8 chromosomal changes per germinoma (0.5 gains vs 1.3 losses), 5.5 per mixed teratoma-germinoma (3.0 gains vs 2.5 losses), 3.5 per immature teratoma (2.0 gains vs 1.5 losses), and 2.0 in the yolk sac tumor (2 gains vs 0 losses) were found; the first recurrence showed 7 (4 gains vs 3 losses), the second 13 imbalances (8 gains vs 5 losses). The most frequent imbalances were gains on 12p (40%), 8q (27%), and 1q (20%) as well as losses on 13q (47%), 18q (33%), 9q and 11q (20% each). Among germinomas, the most common chromosomal changes were -13q and -18q (38% each), in mixed teratomas-germinomas +8q (100%), +12p (75%), -13q (75%) and -9q (50%). Seven high-level gains were identified: 5 in mixed teratomas-germinomas (+8q: 3 cases, + 12p: 2 cases), 1 each in a germinoma (+2p) and an immature teratoma (+12p). Minimal common regions of over- and underrepresentation were found on +8q11.22-21.1, +12p11.1-12.1, -9q32-qter, -11q23.2-qter, -13q32-qter and -18q22-qter. Our findings suggest, that imbalances in cerebral germ cell tumors affect the same chromosomes as among their extracerebral counterparts, albeit in a considerably lower frequency among cerebral germinomas where +12p does not seem to play a major role.

Adolescent↗