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PubMed2000

Non-Alzheimer dementias.

The past decade has seen a considerable resurgence of interest in non-Alzheimer forms of neurodegenerative dementia. Advances in our understanding and classification of these conditions have taken place over a diverse range of disciplines: from genetics and immunohistochemistry to neuropsychology and psychiatry. The aim of this article is to review, from a clinician's perspective, our current understanding of the major degenerative dementias that fall into the differential diagnosis of Alzheimer's disease. The clinical variants of frontotemporal dementia (semantic dementia, progressive nonfluent aphasia, and dementia of a frontal type), amyotrophic lateral sclerosis associated dementia, corticobasal degeneration, and dementia with Lewy bodies are considered.

Amyotrophic Lateral Sclerosis↗

PubMed2004

Diversity and distribution of Microcystis (Cyanobacteria) oligopeptide chemotypes from natural communities studied by single-colony mass spectrometry.

Microcystis sp. has been recognized in recent years as a producer of a high number of secondary metabolites. Among these, peptides that are produced by the non-ribosomal peptide synthetase pathway often show bioactivity or are toxic to humans. The production of particular peptides is specific for individual Microcystis clones, allowing their characterization as chemotypes by analysing the peptidome. The authors studied the in situ diversity of peptides and chemotypes in Microcystis communities from lakes in and around Berlin, Germany, by direct analysis of individual colonies by MALDI-TOF mass spectrometry. From 165 colonies analysed a total of 46 individual peptides could be identified, 21 of which have not been described previously. For six of the new peptides the structures could be elucidated from fragment patterns, while for others only a preliminary classification could be achieved. In most colonies, two to ten individual peptides were detected. In 19 colonies, 16 of which were identified as M. wesenbergii, no peptide metabolites could be detected. The peptide data of 146 colonies were subjected to an ordination (principal components analysis). The principal components were clearly formed by the microcystin variants Mcyst-LR, -RR and -YR, anabaenopeptins B and E/F, a putative microviridin, and a new cyanopeptolin. In the resulting ordination plots most colonies were grouped into five distinct groups, while 40 colonies scattered widely outside these groups. In some cases colonies from different lakes clustered closely, indicating the presence of similar chemotypes in the respective samples. With respect to colony morphology no clear correlation between a chemotype and a morphospecies could be established, but M. aeruginosa, for example, was found to produce predominantly microcystins. In contrast, M. ichthyoblabe colonies were mostly negative for microcystins and instead produced anabaenopeptins. The number of peptides detected in a limited number of samples and the various combinations of peptides in individual Microcystis colonies highlights the immense metabolic potential and diversity of this genus.

Fresh Water↗

PubMed1993

Giant congenital nevi: a conceptualization of patterns.

Patterns in giant congenital nevi are classified as to extent of cellular involvement of the reticular dermis and by the quality of the fibrous matrix. In addition, classifications are influenced by degrees of cellular atypia. Two general categories are defined. In one, the phenomena are relatively independent of those operative at the dermal-epidermal interface. The lesions are characterized as dermal congenital tumorous dysplasias-blastomas. They are subdivided into major, intermediate, and minor categories and into mature and immature variants. In these variants, disparate populations in the patterns of nodules and plaques (lumpy-bumpy variants) qualify as dermal variants of minimal deviation melanoma as seen in the setting of giant congenital nevi. The respective melanomas in this category are small-cell malignant neoplasms (melanoblastomas of infancy and childhood). In a second category in the clinical setting of giant congenital nevus, rare childhood and some adult melanomas of a more common histologic type evolve from lentiginous and junctional components in patterns that recapitulate those of the dysplastic nevus syndrome. The suspicious areas in all categories are evaluated by the same clinical criteria. In the dysplasia-blastoma category, enlarging nodules must be biopsied. The criteria for the evaluation of lesions in the dysplastic nevus syndrome and in the category of minimal deviation melanoma have application to the unstable regions in giant congenital nevi.

Humans↗

PubMed2026

Somatic genetic alterations in pituitary neuroendocrine tumors.

The molecular characterization of pituitary neuroendocrine tumors (PitNETs) has progressed pronouncedly in recent years, unraveling the molecular pathways driving initiation and progression of different PitNET types and allowing a better understanding of their biology. The most frequent recurring somatic driver alterations were recognized in corticotroph PitNETs (USP8, USP48, BRAF) and somatotroph PitNETs (GNAS) and, much less frequently, in lactotroph PitNETs (SF3B1). Additional well-characterized somatic driver alterations, including TP53, ATRX, and DAXX, are enriched in aggressive corticotroph tumors. Identification of new molecular markers and delineation of their clinical phenotypes are enabling further subclassification of PitNETs based on tumor molecular profiles, with earlier recognition of more aggressive variants. These molecular markers also provide an opportunity for new targeted therapies. Beyond single-gene alterations, epigenetic modifications, such as DNA methylation, histone modifications, and noncoding RNA dysregulation, are emerging as important contributors to PitNET pathogenesis and potential therapeutic targets. Multi-omics approaches encompassing genomics, transcriptomics, epigenomics, and proteomics are transforming PitNET classification. In this review, we provide a comprehensive, data-driven update on somatic driver alterations, epigenetic alterations, converging signaling pathways, and the related emerging therapeutic targets in PitNETs, integrating pooled analyses from published cohorts.

Humans↗

PubMed1988

Achondrogenesis-hypochondrogenesis: the spectrum of chondrogenesis imperfecta. A radiological, ultrasonographic, and histopathologic study of 23 cases.

In the classification of lethal osteochondrodysplasias, achondrogenesis and hypochondrogenesis have recently received special attention. We describe 23 cases representing the different subtypes. Within the classical type I (Parenti-Fraccaro) two distinct disorders can be recognized: type IA (Houston-Harris) and type IB (Fraccaro). The classical type II (Langer-Saldino) and hypochondrogenesis represent phenotypic variants of one disorder in which type II is the most severe form and hypochondrogenesis the mildest form, while transitional forms exist. It is likely that a basic defect in cellular function of the chondrocyte results in a deficient cartilage matrix and in disorganized enchondral ossification.

Bone Matrix↗

PubMed2026

sWGS Identifies a Copy-Number-High Subset of TP53-mutated Multiple-Classifier Endometrial Carcinomas With Adverse Clinicopathological Features.

TP53-mutated "multiple-classifier" endometrial carcinomas represent a diagnostically challenging subgroup within current molecular classification algorithms. Although these tumors are assigned to POLE-mutated or mismatch repair-deficient categories according to current ESGO/FIGO-based algorithms, their biological heterogeneity remains incompletely characterized. Herein, we retrospectively analyzed TP53-mutated multiple-classifier endometrial carcinomas identified through routine molecular profiling at our institution between 2022 and 2025 using an integrated histopathological, immunohistochemical, targeted sequencing, and shallow whole-genome sequencing approach. Copy-number alteration-high (CNA-high) status was defined as ≥5 large-scale genomic alterations, corresponding to copy-number gains or losses ≥3 Mb within a single chromosomal arm excluding whole-arm alterations. Among 33 analyzable TP53-mutated multiple-classifier endometrial carcinomas, sWGS identified 12 CNA-high tumors (36.4%) and 21 CNA-low tumors (63.6%). CNA-high tumors were more frequently non-endometrioid, high-grade, and advanced-stage according to FIGO 2023. They showed higher TP53 variant allele frequencies (VAF) and higher TP53 VAF-to-tumor-cellularity ratios. After a median follow-up of 12.8 months, recurrences (6/33; 18.2%) and disease-related deaths (3/33; 9.1%) were observed in the CNA-high subgroup, whereas no recurrence or disease-related death was observed among CNA-low patients. These findings indicate that TP53-mutated multiple-classifier endometrial carcinomas comprise biologically distinct subsets that are not fully captured by current 4-tier TCGA-based molecular classification and ESGO-based risk stratification. In this cohort, sWGS identified a CNA-high group with adverse clinicopathological features and clinical events suggesting a potentially more aggressive clinical course. Integration of genome-wide copy-number profiling may therefore refine the biological interpretation of TP53 alterations in multiple-classifier endometrial carcinomas and warrants validation in larger multicenter cohorts.

TP53↗

PubMed1986

Chemical classification of hereditary amyloidosis in Brazilian families and identification of gene carriers.

Plasma prealbumin was isolated from individuals in 3 kindreds from Brazil with biopsy proven heredofamilial amyloidosis as well as from a number of asymptomatic family members. The prealbumin samples were cleaved with cyanogen bromide and the resulting peptide mixtures separated by reverse phase high performance liquid chromatography. The peptide elution pattern seen for the individuals with confirmed amyloidosis is consistent for the presence of a prealbumin variant with a methionine for valine at position 30 of the molecule. Sequence analysis of the isolated peptides confirms this observation and shows that the 3 Brazilian families investigated in our study have the same prealbumin variant as individuals with amyloidosis of Swedish/American, Portuguese and Japanese origins.

Adult↗

PubMed2003

Revision of the International Neuroblastoma Pathology Classification: confirmation of favorable and unfavorable prognostic subsets in ganglioneuroblastoma, nodular.

BACKGROUND: Ganglioneuroblastoma, nodular (GNBn) comprises one of the categories of peripheral neuroblastic tumors. All tumors in this category, according to the original International Neuroblastoma Pathology Classification, are classified into an unfavorable histology group. Subsequently, it has been reported that GNBn can be divided into two prognostic subsets, a favorable subset (FS) and an unfavorable subset (US). METHODS: Histology slides from 70 patients who were enrolled in Children's Cancer Group studies 3881 and 3891 and who had a diagnosis of GNBn were reviewed jointly by the members of International Neuroblastoma Pathology Committee (INPC): 1) to confirm the diagnosis of GNBn, 2) to identify the FS and US by applying the same age-linked criteria that were used to distinguish the favorable histology group and unfavorable histology group in conventional neuroblastoma tumors from the neuroblastomatous component of GNBn tumors, and 3) to verify the significant prognostic difference between these two subsets. The patients had been used in a previous study, and survival data for the patients were updated since the time of their last report. RESULTS: The review clarified and illustrated morphologic characteristics of classical GNBn and it variants. The diagnosis of GNBn was confirmed in 67 of 70 patients. There were 22 patients with GNBn in the FS and 45 patients with GNBn in the US. The estimated survival differences between the FS and US patients with GNBn were statistically significant (8-year event free survival rate: 86.1% vs. 32.2%; P = 0.0003; overall survival rate: 90.5% vs. 33.2%; P = 0.0003). CONCLUSIONS: This study confirmed the recently defined prognostic subsets of GNBn. The INPC proposes to modify the International Neuroblastoma Pathology Classification by distinguishing the FS and the US among patients with GNBn tumors.

Child↗

PubMed1995

Post-resuscitation disease--a new nosological entity. Its reality and significance.

Experimental and clinical investigations of patients resuscitated after cardiac arrest or terminal states, testify to the fact that in the post-resuscitation period alongside processes of recovery and compensation, a number of new pathological phenomena develop. The latter differ substantially from those caused by ischemia and hypoxia. These post-resuscitation processes involve not only the CNS, but also the entire body and may lead to severe disability and even death of the seemingly successfully revived body. The data available suggests that this post-resuscitation pathology is a new nosological entity--a post-resuscitation disease. This disease has it own specific etiology, pathogenesis, variants of the clinical course (a number of syndromes) and the system of treatment and rehabilitation. In view of the ever wider use of resuscitation in clinical practice, it is expedient to organize an all-round study of this nosological entity, the optimum systems of its treatment, and to include this entity into International Classification of Diseases of WHO.

Central Nervous System Diseases↗

PubMed2005

(Patho-)Genomics of Escherichia coli.

Escherichia coli represents a versatile and diverse enterobacterial species which can be subdivided into (i) nonpathogenic, commensal, (ii) intestinal pathogenic and (iii) extraintestinal pathogenic strains. This classification is mainly based on the presence or absence of DNA regions which are frequently associated with certain pathotypes. In most cases, this genetic information has been horizontally acquired and belongs to the flexible E. coli genome, such as plasmids, bacteriophages and genomic islands. These genomic regions contribute to the rapid evolution of E. coli variants as they are frequently subject to rearrangements, excision and transfer as well as further acquisition of additional DNA thus contributing to the creation of new (pathogenic) variants. Genetic diversity and genome plasticity of E. coli has been underestimated. The accumulating amount of sequence information generated in the era of "genomics" helps to increase our understanding of factors and mechanisms that are involved in diversification of this bacterial species as well as in those that may direct host specificity.

Bacteriophages↗

PubMed1985

Ontogeny modifies manifestations of cystinuria genes: implications for counseling.

Among 339,868 newborn infants screened at 3 weeks of age (91% compliance rate), 730 had elevated rates of excretion of cystine and the dibasic amino acids lysine, ornithine, and arginine; 191 infants had persistent "infantile cystinuria" on follow-up screening (100% compliance). Apparent incidence of the phenotype was 562 per million infants; this rate is seven times higher than for classic cystinuria in the adult segment of the Quebec population. We studied longitudinally 26 probands 2 to 4 months of age. Initially, each excreted cystine and dibasic amino acids at much higher levels than did normal infants or either parent. From parental phenotypes (heterozygous or homozygous normal) and urine amino acid excretion values at 6 months of age in probands, the infants were classified as either heterozygous for the various classic cystinuria genotypes--type I ("silent"), eight infants; type II (high excretor), three; type III (moderate excretor), nine--or homozygous (and genetic compound), six. Urine amino acid excretion diminished steadily with age, to reach the variant parental value in heterozygous infants but not in homozygotes. Cystinuria heterozygotes, with the possible exception of some type I individuals, could not be distinguished reliably from homozygotes in early infancy, although homozygotes had significantly higher excretion values as a group. We deduce that renal ontogeny amplifies phenotypic expression of cystinuria alleles, thus influencing correct classification of genotype (heterozygote vs homozygote, and type of allele). These findings have implications for counseling and the need for follow-up of infantile cystinuria.

Aging↗

PubMed2004

Imaging in head and neck oncology.

Evaluation of head and neck cancer with imaging is a topic that is far more extensive than can be covered in this article. The main reason for head and neck imaging is to evaluate the true extent of disease to best determine surgical and therapeutic options. This process includes evaluation of the size, location, and extent of tumor infiltration into surrounding vascular and visceral structures. Important anatomic variants must be pointed out so the surgeon can avoid potential intraoperative complications. These variant scan be evaluated with the appropriate multiplanar and three-dimensional images to provide as much information as possible to the surgeon preoperatively. Second, nodal staging should be assessed in an effort to increase the number of abnormal nodes detected by physical examination and, more important, to precisely define their location by a standard classification system that can be understood and consistently applied by the radiologist, surgeon, radiation oncologist, and pathologist. Although secondary to the previously described tasks, imaging frequently enables a limitation of the diagnostic and histologic possibilities based on lesion location and signal-attenuation characteristics, which may lead the clinical investigation along a different path. saving the patient unnecessary risk and shortening the time to diagnosis and ultimate treatment. This article has attempted to detail the current state of the controversy between CT, MRI, and other modalities, and has emphasized the constant evolution of this controversy because of the evolving imaging technology. Although CT and MRI are both well suited to evaluation of the deep spaces and submucosal spaces of the head and neck, each has some limitations.MRI has the advantages of higher soft tissue contrast resolution, the lack of iodine-based contrast agents, and high sensitivity for perineural and intracranial disease. The disadvantages of MRI include lower patient tolerance, contraindications in pacemakers and certain other implanted metallic devices, and artifacts related to multiple causes, not the least of which is motion. CT is fast, well tolerated, and readily available but has lower contrast resolution and requires iodinated contrast and ionizing radiation. The current authors' practice is heavily centered on CT for initial evaluation, preoperative planning, biopsy targeting, and postoperative follow-up. They reserve MRI for tumors that are suspicious for perineural,cartilaginous, or bony invasion on CT, or for tumors such as adenoid cystic carcinoma that are highly likely to spread by way of these routes. For patients who have head and neck cancer, a radiologist who is educated in the treatment options, patterns of tumor growth, and important surgical landmarks, and who has a well-established pattern of communication with the head and neck clinical services, including surgery, radiation oncology,and pathology, is key in providing accurate and useful image interpretation.

Carcinoma, Squamous Cell↗

PubMed1992

From the jumping Frenchmen of Maine to post-traumatic stress disorder: the startle response in neuropsychiatry.

The startle response is a universal and phylogenetically ancient reflex. Pathological exaggerations and modifications of startle underlie the symptomatology of a surprisingly diverse range of neuropsychiatric disorders, a fact that seems to have gone largely unappreciated. We review the available literature on the physiology of the normal human startle response and examine the neuropsychiatric conditions characterized by pathological startle. Startle epilepsy and primary hyperekplexia are considered as neurological disorders involving abnormal startle. Patients with hyperstartle and exotic culture-bound syndromes characterized by excessive startle are considered by the authors to represent extreme variants of the normal startle response. Post-traumatic stress disorder, drug and alcohol withdrawal states and schizophrenia all have abnormal startle as a clinical feature secondary to increased arousal and presumed disturbance of central neurotransmitter systems. The neurophysiological mechanisms by which abnormalities of the startle response may occur are discussed and a system of classification of neuropsychiatric hyperstartles is suggested.

Humans↗

PubMed1967

Life cycle and variation of Prototheca wickerhamii.

Prototheca wickerhamii is a yeastlike organism that resembles the green alga Chlorella. Nuclear division in coordination with cytoplasmic cleavage gives rise to uninucleate cytoplasmic segments, each of which acquires a delicate cell wall and develops into an autospore. The autospores in this species are spherical; but in a variant that presumably arose as a result of spontaneous mutation, the cytoplasmic cleavage is irregular, and the resultant autospores are ovoid to bacillary. When these variant autospores grow, they swell and round up before the nuclear division begins, producing spherical cells like those seen in wild-type cultures. In view of the fact that species concept in the genus is based on size and shape of cells, the variation limits in these morphological characteristics have significant bearing on species classification.

Culture Media↗

PubMed2004

Multi-component based cross correlation beat detection in electrocardiogram analysis.

BACKGROUND: The first stage in computerised processing of the electrocardiogram is beat detection. This involves identifying all cardiac cycles and locating the position of the beginning and end of each of the identifiable waveform components. The accuracy at which beat detection is performed has significant impact on the overall classification performance, hence efforts are still being made to improve this process. METHODS: A new beat detection approach is proposed based on the fundamentals of cross correlation and compared with two benchmarking approaches of non-syntactic and cross correlation beat detection. The new approach can be considered to be a multi-component based variant of traditional cross correlation where each of the individual inter-wave components are sought in isolation as opposed to being sought in one complete process. Each of three techniques were compared based on their performance in detecting the P wave, QRS complex and T wave in addition to onset and offset markers for 3000 cardiac cycles. RESULTS: Results indicated that the approach of multi-component based cross correlation exceeded the performance of the two benchmarking techniques by firstly correctly detecting more cardiac cycles and secondly provided the most accurate marker insertion in 7 out of the 8 categories tested. CONCLUSION: The main benefit of the multi-component based cross correlation algorithm is seen to be firstly its ability to successfully detect cardiac cycles and secondly the accurate insertion of the beat markers based on pre-defined values as opposed to performing individual gradient searches for wave onsets and offsets following fiducial point location.

Algorithms↗

PubMed1976

Intra-oral shape recognition by 138 mentally retarded subjects.

Among Ss with normal intelligence, oral shape-recognition tests have shown a relationship between articulatory ability and oral sensory integrity. This investigation explored oral sensory impairment as a possible contributory cause of the articulatory difficulties exhibited by the mentally retarded. The Florida Oral-form Recognition Measure (FORM), a task requiring the intra-oral identification of 10 geometric shapes, was administered to 138 mentally retarded Ss. Twenty Ss were retested to establish reliability. Ss were placed in groups according to etiological categories (AAMD classification) and were assigned speech ratings by a speech pathologist. Of the total sample, 86% had varying degrees of defective speech or language. Mean FORM score was 3.5, and preliminary analysis yielded significant correlations between FORM score and IQ and between speech and language rating. Further multivariate analysis with IQ held as a co-variant indicated no significant relationship between FORM score and communicative ability. This suggests caution in inferring that intra-oral shape-recognition scores reflect degree of oral sensory integrity. Perhaps a battery of oral perceptual tasks might more validly assess oral sensation-perception and aid in clarifying its relationship to speech.

Adolescent↗

PubMed2005

Asymmetric interference between sex and emotion in face perception.

Previous research with speeded-response interference tasks modeled on the Garner paradigm has demonstrated that task-irrelevant variations in either emotional expression or facial speech do not interfere with identity judgments, but irrelevant variations in identity do interfere with expression and facial speech judgments. Sex, like identity, is a relatively invariant aspect of faces. Drawing on a recent model of face processing according to which invariant and changeable aspects of faces are represented in separate neurological systems, we predicted asymmetric interference between sex and emotion classification. The results of Experiment 1, in which the Garner paradigm was employed, confirmed this prediction: Emotion classifications were influenced by the sex of the faces, but sex classifications remained relatively unaffected by facial expression. A second experiment, in which the difficulty of the tasks was equated, corroborated these findings, indicating that differences in processing speed cannot account for the asymmetric relationship between facial emotion and sex processing. A third experiment revealed the same pattern of asymmetric interference through the use of a variant of the Simon paradigm. To the extent that Garner interference and Simon interference indicate interactions at perceptual and response-selection stages of processing, respectively, a challenge for face processing models is to show how the same asymmetric pattern of interference could occur at these different stages. The implications of these findings for the functional independence of the different components of face processing are discussed.

Adolescent↗

PubMed1988

[Colitic variant of the gastrointestinal form of salmonellosis].

Of 3327 hospitalized patients with salmonellosis, a clinical picture of isolated distal colitis was noted in 142 (4.3%). Acute dysentery was diagnosed in them before the results of bacteriological stool examination were ready. In this variant of salmonellosis S. enteritidis and S. haifa were detected twice as more frequently than in the other variants. As compared to dysentery, the colitic variant of salmonellosis was characterized by more marked intoxication syndrome whereas stomach pains were less spasmodic, less frequently localized in the sigmoid colon; important symptoms for differential diagnosis like tenesmus, false rectal tenesmus, pains and spasms of the sigmoid colon were less frequently noted. Therefore this type of salmonellosis should be included in the clinical classification of salmonellosis of adults on the basis of an obvious clinical picture.

Acute Disease↗