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PubMed1984

Esterases of earthworms--III. Electrophoresis reveals that Eisenia fetida (Savigny) is two species.

Polyacrylamide gel electrophoresis of esterases in earthworms classified as Eisenia fetida (Savigny) revealed the existence of two species. The classification based upon esterase electromorphs coincided with classification into two colour variants formerly described as subspecies under the names E. fetida typica and E. fetida unicolor (André, 1963). Two main groups of esterases, acetylesterases and carboxylesterases were found. Because of less variability within species and higher stability the acetylesterases are regarded as the most useful in taxonomy. Sterile hybrids, with hybrid esterase patterns were produced at a low rate in the laboratory, but were never found with certainty in the wild populations. Eisenia fetida (Savigny) and Eisenia unicolor (André) are the names proposed for the two species.

Animals↗

PubMed2006

Novel low-grade glioneuronal neoplasm presenting in an octogenarian: case report and review of the literature.

Glioneuronal neoplasms are rare tumors that typically affect patients in the first three decades of life. Since the publication of the World Health Organization (WHO) 2000 classification of tumors, further variants of these tumors have been reported. We present an 83-year-old gentleman who presented with a history of ataxia and weight loss. MRI and CT scan revealed a ring-enhancing bihemispheric lesion in the premotor cortex consistent with a malignant primary brain tumor crossing the corpus collosum. The patient underwent a sterotactic biopsy with drainage of the cystic component. Histopathologic studies revealed a mixed glioneuronal tumor with benign characteristics. A craniotomy was performed and the tumor was resected. Postoperatively, the patient has been followed with serial MRI scans with no evidence of disease recurrence at 27 months. Glioneuronal tumors are extremely uncommon in the octogenarian population, however, it is important to include them in the differential diagnosis of intracerebral masses. They are histopathologically quite heterogeneous, and in this report we present a novel subtype. Radiographically, these lesions can mimic more aggressive primary brain tumors.

Aged↗

PubMed2001

Charcot-Marie-Tooth disease (CMT): distinctive phenotypic and genotypic features in CMT type 2.

Charcot-Marie-Tooth disease (CMT), or hereditary motor and sensory neuropathy (HMSN), includes two main subtypes of CMT1/HMSN I (demyelinating), and CMT2/HMSN II (axonal). Further heterogeneity has been demonstrated by genetic molecular studies, with at least four responsible genes for CMT1. As for CMT2, a mutation in the neurofilament-light (NF-L) gene has been identified in a single family, and other CMT2 loci have been mapped. We propose a clinical classification of the CMT2 phenotypes, and review the features of the identified CMT2 genotypes. The following main subtypes of CMT2 are considered in the phenotype classification: classical CMT2, the variants of CMT2 showing atypical features that may represent either variance in the classical CMT2 phenotype or separate entities; CMT2 plus, i.e. complex forms with involvement of additional neural structures. The recognized CMT2 genotypes include: CMT2A (mapped to chromosome 1p35-36); CMT2B (3q13-22); CMT2C (with vocal cord paresis); CMT2D (7p14); CMT2E, related to a mutation in the NF-L gene on chromosome 8p21; proximal CMT2, or HMSN P (3q13.1); CMT2 with MPZ mutations; autosomal recessive CMT2 (1q21.2-q21.3); agenesis of the corpus callosum with sensorimotor neuronopathy (15q13-q15); CMT2 X-linked with deafness and mental retardation (Xq24-q26). The identified genotypes may correspond to previously described clinical subtypes of CMT2. In particular, classical CMT2 presents in association with NF-L gene mutation, in the only CMT2 family with known gene mutation, and in CMT2A patients. However, the features of classical CMT2 have been paradoxically reported also in families with MPZ mutation, and conversely several CMT2 families are not linked to the known CMT2 loci. Further cloning of the CMT2 genes will ultimately shed light on the pathogenic mechanism(s) implicated in the process of axonal degeneration, shared by the different CMT2 genotypes.

Charcot-Marie-Tooth Disease↗

PubMed1981

Mesenchymal renal tumors in infancy: a reappraisal.

Eight cases of primary mesenchymal renal tumor in infants under one year of age were studied. The patients' ages ranged from one day to seven months; all but one were diagnosed within the first three months of life. There were four typical congenital mesoblastic nephromas. Two malignant mesenchymal, one intermediate case of difficult classification designated as "cellular variant" of congenital mesoblastic nephroma, and one hemangioendothelioma. All patients were alive and free of tumor 3 9/12 to 18 10/12 years after surgery. Of the four infants with congenital mesoblastic nephroma, one was treated by tumor excision alone; nearly 13 years later this patient was free of tumor. A high degree of cellularity and a high nucleus-cytoplasm ratio were features that characterized the tumor diagnosed as "cellular variant" of congenital mesoblastic nephroma. A sarcomatous gross appearance with cavitation necrosis was seen in the two instances of malignant mesenchymal nephroma; one of these metastasized to the lung, whereas in the other, though no metastases developed, all the histologic details of the previous case were reproduced, including distinct foci of necrosis and a high mitosis rate. Mesenchymal renal tumors in young infants constitute a set more heterogeneous than has been previously assumed. They should not be considered uniformly benign. As a group, they span the whole spectrum between benign, morphologically quiescent lesions, clinically and pathologically intermediate or indeterminate ones, and outright malignant tumors with a high risk of distant spread.

Female↗

PubMed1987

Syringoma presenting as milia.

We present two unrelated patients with numerous infraocular milium-like lesions that histologically revealed syringoma with many overlying keratin cysts in the papillary dermis. A Fontana-Masson stain revealed no melanin-containing cells in the keratin cyst walls, suggesting that they originated from eccrine ductal structures. A classification of the clinical variants of syringoma is presented.

Adenoma↗

PubMedDate not supplied

Ring-shaped lateral meniscus.

The existence of abnormal-shaped menisci has been long recognized. The presence of discoid menisci in the human knee is considered to be a congenital malformation with a very low rate of incidence except in Asian populations. Since the publication of Watanabe's Atlas, three types of lateral meniscal abnormalities are generally accepted: the complete and incomplete discoid, as well as the Wrisberg-ligament type meniscus. The present case is the second description of a ring-shaped meniscus on the lateral side of the knee and we propose that this variant be included as a fourth variant in a future classification.

Adult↗

PubMed1984

A case of malignant myxoma (myxosarcoma) of the maxilla.

A centrally located maxillary myxoma with malignant histologic appearance and aggressive clinical course is reported in a 40-yr-old man. The gelatinous polypoid tumor mass was diagnosed as a myxoma in the first biopsy. The tumor recurred rapidly (within 3 wk) eroding the bony structures of the maxillary sinus and the hard palate and infiltrating the adjacent soft tissues. In repeated biopsy (as well as reassessment of the first biopsy) the tumor was found to be composed of plump stellate cells, some of which were pleomorphic with atypical and bizarre mitotic figures. The amorphic myxoid matrix contained acid mucopolysaccharides and was completely devoid of lipids. Electron microscopy demonstrated that the tumor cells were identical to fibroblasts, which is consistent with the appearance of myxoma cells. When radiotherapy was unsuccessful, we removed the left maxilla with orbital excenteration and reconstructed the jaw. Three years later the patient died accidentally. At autopsy, no recurrence of myxoma or distant metastases were found. Due to the malignant histologic appearance and the aggressive clinical course, this tumor can be called an odontogenic myxosarcoma and should be added to the WHO classification as a malignant variant of odontogenic myxoma.

Adult↗

PubMed1993

Dysembryoplastic neuroepithelial tumours.

Dysembryoplastic neuroepithelial tumours (DNTs) are a group of supratentorial cortical benignant lesions that superficially resemble mixed oligo-astrocytomas, oligodendrogliomas or astrocytomas. Clinically these tumours are associated with partial seizures beginning before the age of 20 years, with no neurologic deficit and no stigmata of phacomatosis. In the revised WHO classification, DNTs have been incorporated among the category of neuronal and mixed neuronoglial tumours. This classification describes a histologic variant characterized by the following criteria: cortical location, multinodular architecture--the nodule being made of multiple variants looking like astrocytomas, oligodendrogliomas or oligo-astrocytomas, foci of dysplastic cortical disorganization and the presence of a glioneuronal element showing a columnar structure perpendicular to the cortical surface. A study of 14 cases for which only a specific glioneuronal element could be identified demonstrated that this specific element is sufficient for diagnosing DNTs and that the spectrum of DNTs includes a simple form with a unique glioneuronal element. Preoperative imaging follow-up data, in the series of 23 simple and complex forms, indicated that DNTs are perfectly stable. However, these tumours may show a high MIB 1 labeling index.

Brain Neoplasms↗

PubMed1984

Primary tumorous aldosteronism due to a black adrenal adenoma: a light and electron microscopic study.

A case of primary tumorous aldosteronism due to a black adrenal adenoma in a 37-year-old man is reported. Light microscopy showed the tumour to consist predominantly of compact cells containing intracytoplasmic lipofuscin, accompanied by zona fasciculata and intermediate type cells. Electron microscopy identified compact and interface (inner zona fasciculata) type cells, and also demonstrated spironolactone bodies in a compact cell. The morphological appearance of the tumour and adjacent adrenal gland, combined with the clinical and biochemical findings, supports both its secretory function and its classification as a rare variant of the more common non-pigmented aldosteronoma.

Adenoma↗

PubMed1995

Hepatic arterial anatomy: demonstration of normal supply and vascular variants with three-dimensional CT angiography.

Three-dimensional (3D) helical computed tomographic (CT) angiography is a promising method of determining vascular anatomy. This technique is useful in delineating the arterial anatomy of the liver, demonstrating the normal anatomy and vascular variants in a highly visual fashion. The "typical" hepatic arterial anatomy occurs in only 55% of the population, and numerous variants exist; the standard classification system for hepatic arterial anatomy includes 10 variations. After helical scanning, postprocessing with reconstruction algorithms such as shaded surface display and maximum-intensity projection provides highly graphic, easily understandable views of vascular anatomy. The 3D CT angiograms, with their global view of the anatomy and inherent advantage of volumetric rotation of the vascular system, are useful to surgeons and others with limited experience in interpreting axial anatomy. Determination of hepatic arterial anatomy with 3D CT angiography has already been shown to be clinically useful in patients being evaluated for liver transplantation.

Adult↗

PubMed1996

Angiokeratomas: an update.

Angiokeratomas are vascular lesions which are defined histologically as one or more dilated blood vessel(s) lying directly subepidermal and showing an epidermal proliferative reaction. At the center of pathogenesis there is a capillary ectasia in the papillary dermis. The epidermal changes in all forms of angiokeratoma are secondary. The different entities causing vessel ectasia lead to the many clinical variants of angiokeratoma. Current classification distinguishes between widespread forms (angiokeratoma corporis diffusum), which is usually associated with an inborn error of metabolism, and localized forms, which include solitary angiokeratoma, Fordyce's angiokeratoma, angiokeratoma circumscriptum naeviforme and angiokeratoma of Mibelli.

Angiokeratoma↗

PubMed1996

Dysmorphophobia: differential-diagnostic aspects.

The case of a patient presenting with a depressive-suicidal syndrome and dysmorphophobia, which also showed a delusional character, is discussed concerning the differential-diagnostic difficulties. The nosology of the disorder is discussed especially regarding the variants in the new classification systems.

Adult↗

PubMed2006

Autoimmune neuropsychiatric disorders associated with streptococcal infection: Sydenham chorea, PANDAS, and PANDAS variants.

Streptococcal infection in children is usually benign and self-limited. In a small percentage of children, prominent neurologic and/or psychiatric sequelae can occur. Sydenham chorea is the best defined and best recognized. PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection) is a well-defined syndrome in which tics (motor and/or vocal) and/or obsessive-compulsive disorder consistently exacerbate in temporal correlation to a group A beta-hemolytic streptococcal infection. PANDAS constitutes a subset of children with tics, Tourette syndrome, and obsessive-compulsive disorder. In addition to strictly defined PANDAS, we and others have recognized several PANDAS variants, including adult-onset variant, a dystonic variant, a myoclonic variant, and a "chronic" PANDAS variant. The nosology and classification of these entities are rapidly evolving. The recognition that some pediatric neurobehavioral syndromes have infectious and/or immunologic triggers points to important new avenues of disease treatment. In this review, we summarize this complex and rapidly evolving area of clinical research.

Adolescent↗

PubMed2006

Comparative analysis of hepatitis C virus phylogenies from coding and non-coding regions: the 5' untranslated region (UTR) fails to classify subtypes.

BACKGROUND: The duration of treatment for HCV infection is partly indicated by the genotype of the virus. For studies of disease transmission, vaccine design, and surveillance for novel variants, subtype-level classification is also needed. This study used the Shimodaira-Hasegawa test and related statistical techniques to compare phylogenetic trees obtained from coding and non-coding regions of a whole-genome alignment for the reliability of subtyping in different regions. RESULTS: Different regions of the HCV genome yield inconsistent phylogenies, which can lead to erroneous conclusions about classification of a given infection. In particular, the highly conserved 5' untranslated region (UTR) yields phylogenetic trees with topologies that differ from the HCV polyprotein and complete genome phylogenies. Phylogenetic trees from the NS5B gene reliably cluster related subtypes, and yield topologies consistent with those of the whole genome and polyprotein. CONCLUSION: These results extend those from previous studies and indicate that, unlike the NS5B gene, the 5' UTR contains insufficient variation to resolve HCV classifications to the level of viral subtype, and fails to distinguish genotypes reliably. Use of the 5' UTR for clinical tests to characterize HCV infection should be replaced by a subtype-informative test.

5' Untranslated Regions↗

PubMed1988

Perinatal lethal osteogenesis imperfecta: radiologic and pathologic evaluation of seven prenatally diagnosed cases.

The radiologic and pathologic characteristics of 7 cases of lethal osteogenesis imperfecta (OI), diagnosed prenatally by ultrasound in the 15th to 34th week, are described. They include four variants of the Sillence classification: types IIA, IIB, IIC, and type III. The radiologic criteria that differentiate these types of OI are described. The histopathology of the bones differed only slightly in types IIA, IIB, and III; OI type IIC, however, differed markedly from the other types.

Female↗

PubMed1982

Identification of a new Venezuelan equine encephalitis virus from Brazil.

Two strains of recently isolated Venezuelan equine encephalitis (VEE) complex virus from southern Brazil, avirulent for 6- to 8-week-old mice and short-haired guinea pigs, were characterized by biologic, serologic, and biochemical means. They were shown serologically to represent a single, newly recognized variant of subtype I. Two-dimensional polyacrylamide gel electrophoresis (PAGE) of ribonuclease T1 digests of viral ribonucleic acid showed considerable homology between the genomes of the new variant prototype and variant IA. Three structural proteins were visualized by discontinuous sodium dodecyl sulfate-PAGE (SDS-PAGE). Although the smallest protein of both recent isolates migrates with the capsid proteins of other subtype I viruses, the larger structural proteins of the new variants differ in molecular weight from the E1 and E2 envelope glycoproteins of the other subtype I variants. The new isolates produced peptide fragment patterns that were identical to each other, but different from the patterns of other subtype I viruses, following SDS-PaGE of dissociated virions digested with Staphylococcus aureus V8 protease. Since these two isolates were from Culex (Melanoconion) species mosquitoes and from a bat (Carollia perspicillata), were postulated that this is an enzootic VEE virus variant for which the classification IF is suggested.

Animals↗

PubMed2003

Early invasive cervical adenocarcinoma: its potential for nodal metastasis or recurrence.

OBJECTIVE: To investigate the potential for nodal spread or recurrence in patients with early invasive cervical adenocarcinoma. The possible application of the International Federation of Gynecology and Obstetrics (FIGO) classification (1994) to this variant was also examined. DESIGN: Retrospective observational study. SETTING: Gynaecological oncology division of Cancer Institute Hospital, Japan. POPULATION: 302 patients with FIGO Stage 0-IIB cervical adenocarcinoma treated surgically at the Cancer Institute Hospital. METHODS: Clinicopathological analysis was performed on 47 patients with early invasive cervical adenocarcinoma in whom the depth of stromal invasion was 5 mm or less. All patients underwent radical hysterectomy and pelvic lymphadenectomy. RESULTS: In 30 patients with a depth of tumour invasion of 3 mm or less, no lymph node metastasis was found, while two patients developed recurrence; one had a depth of invasion of 3 mm and a horizontal tumour spread of 3 mm, and the other had horizontal spread of more than 7 mm. In 17 patients with a depth of invasion from 3 to 5 mm, there was also no lymph node metastasis, but two patients developed recurrence; one had horizontal tumour spread of 7 mm or less, and the other had horizontal spread of more than 7 mm. CONCLUSIONS: Early invasive cervical adenocarcinoma with a depth of invasion of 3 mm or less and a horizontal spread of 7 mm or less has little potential for nodal metastasis or recurrence. It seems possible that the FIGO definition (1994) of early cervical cancer may be applicable in its present form to early cervical adenocarcinoma.

Adenocarcinoma↗

PubMed2003

Pediatric migraines: a case report.

Migraines are a common problem faced by the pediatrician. It can be difficult to determine the difference between a common headache and a migraine in young children. This case report will review a case that presented to the neurologist's office, then discuss the epidemiology, pathophysiology, classification of migraine, migraine variants, clinical evaluation, differential diagnosis, and treatment of migraines in a pediatric population.

Child↗