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PubMed1980

Frequency and morphology of malignant tumours of the thyroid before and after the introduction of iodine-prophylaxis.

Reclassification of malignant goitres surgically removed between 1952-1975 reveals remarkable epidemiological alterations. There is a proportional decrease in undifferentiated carcinoma, which in males also represents an absolute decrease. The decrease is due to a change in maximum incidence from the 5th to the 7th decade. Differentiated carcinomas, especially the papillary tumours, increase. Comparison with findings in Switzerland shows many conformities. Iodine-prophylaxis apparently influences the morphology of thyroid carcinoma, as indicated by the time lag between the introduction of iodine-prophylaxis and the appearance of alterations in incidence. Iodine-prophylaxis, acting in this way, will improve survival rates in thyroid cancer.

Age Factors↗

PubMedDate not supplied

Molecular identification of rRNA group 3 bacilli (Ash, Farrow, Wallbanks and Collins) using a PCR probe test. Proposal for the creation of a new genus Paenibacillus.

Comparative 16S rRNA sequence analysis has demonstrated that the genus Bacillus consists of at least five phyletic lines. rRNA group 3 bacilli of Ash, Farrow, Wallbanks and Collins (1991) comprising Bacillus polymyxa and close relatives is phylogenetically so removed from Bacillus subtilis, the type species of the genus and other aerobic, endospore-forming bacilli that they warrant reclassification in a new genus Paenibacillus. The genus Paenibacillus can be readily distinguished from other Bacillus groups using a battery of phenotypic characters and a highly specific gene probe based on 16S rRNA.

Bacillus↗

PubMedDate not supplied

Taxonomy, virulence and epidemiology of black-pigmented Bacteroides species in relation to oral infections.

Black-pigmented Bacteroides species are recognized as suspected pathogens of oral infections. Developments in the taxonomy of this group include description of a new asaccharolytic species, Bacteroides salivosus, and proposal for the reclassification of the asaccharolytic species into a separate genus, Porphyromonas. Studies on the pathogenicity and virulence of black-pigmented Bacteroides species have identified Bacteroides gingivalis as the most virulent species. B. gingivalis and Bacteroides intermedius have been associated with periodontal diseases; Bacteroides endodontalis is isolated specifically from infections in the oral cavity, and other black-pigmented Bacteroides species are recovered from oral mucous sites. DNA restriction endonuclease analysis was adapted for typing of B. gingivalis and B. intermedius.

Bacteroides↗

PubMed1990

Patterns of contact phase proteins indicating neuropathy in diabetic patients.

In 42 outpatients of the diabetology division, coagulation and fibrinolysis variables were determined in order to detect typical patterns of results with which it was possible to discriminate between three groups with different diabetic complications (17: no complication, 7: angiopathy alone, 18: neuropathy with or without other complications). There was a statistically significant discriminatory function involving C1-inhibitor concentration, high molecular weight kininogen coagulant activity and fibrinogen as the most decisive variables. The neuropathy group was appropriately separated from the others with an 81% correct reclassification. Heparin cofactor II, histidine-rich glycoprotein, alpha 2-macroglobulin, pre-kallikrein and factor XII had no discriminative power.

Adult↗

PubMed1996

Reclassifying causes of death to study the epidemiological transition in the Netherlands,1875-1992.

"This article describes a method for reclassifying causes of death in the Netherlands for the period 1875-1992....A method developed by Vallin and Mesle (1988), which involves ¿dual correspondence tables' and ¿fundamental associations', was used to create nosologically continuous categories. These categories were tested for statistical continuity during the transition years of one ICD-revision [International Classification of Diseases] to the next, using ordinary least squares regression analysis. The reclassification procedure resulted in a nested classification consisting of three levels of refinement of causes of death: 27 causes, 1875-1992; 65 causes, 1901-1992; and 92 causes, 1931-1992. On the basis of this classification, 43% of all deaths in 1875-79 and 98% of all deaths in 1992 could be allocated to either communicable diseases, non-communicable diseases or external causes." (SUMMARY IN FRE)

Cause of Death↗

PubMed1996

Three dimensional staging of breast cancer.

PURPOSE: Breast cancers are three dimensional solids but very few are spherical. We hypothesized that calculations based on the greatest diameter would not accurately reflect tumor volume and that three dimensional measurements would affect tumor staging. MATERIALS AND METHODS: 165 invasive carcinomas measuring 2.5 cm or less and having three measured diameters (a > or = b > or = c) noted were evaluated. Tumor volume was calculated using four geometric models: the spherical 4/3 pi (a/2)3, prolate spheroid 4/3 pi (a/2) (c/2)2, oblate spheroid 4/3 pi (a/2)2 (b/2), and ellipsoid 4/3 pi (a/2 x b/2 x c/2). The ellipsoid correctly determined the volume for any tumor shape. All cases were stratified according to the TNM staging system. Differences in mean volume calculated as a sphere and ellipsoid for each tumor subclass were analyzed using Student's T test. The reclassification of tumors by the ellipsoid formula was determined. RESULTS: Seventy-six (46.1%) had tumors with three different diameters while only six (3.6%) were true spheres having three identical diameters. Mean tumor volume analysis of T1a, T1b, T1c, and T2 tumors demonstrated a statistically significant overestimation of volume when utilizing the sphere formula instead of the ellipsoid formula (p < 0.05). The differences in volume were more dramatic as the diameters increased. A total of 41 tumors were moved into smaller T subclasses including 10 node positive patients. CONCLUSIONS: Tumor volume analysis demonstrates that use of only the greatest diameter poorly reflects the true volume of a lesion and consistently overestimates volume. The ellipsoid formula accurately calculates volume for these three dimensional tumors and when utilized has significant relevance to staging small invasive breast cancers.

Breast Neoplasms↗

PubMed1995

Atypical and anaplastic meningiomas--does the new WHO-classification of brain tumours affect the indication for postoperative irradiation?

We retrospectively analysed 13 patients (pts.) treated at the University of Tübingen from 1985 to 1993 to evaluate the results of radiation therapy (XRT) given as an adjuvant to totally or subtotally resected meningiomas. The overall survival was 38% at five years with a probability of relapse of 50% at this time. Reclassification of the tumours according to the new WHO-classification of brain tumours [14] revealed 10 grade-II-tumours (atypical meningioma) and 3 grade-III-tumours (anaplastic meningioma). Radiotherapy failed in all 3 pts. with macroscopically incomplete resection (Simpson's grade IV), who died with relapse between 4 and 51 months after radiotherapy. 5 out of 10 pts. with grade-II-tumours relapsed. All 3 pts. with grade-III-tumours died with relapse between 6 and 21 months after XRT. Morbidity was seen in 2 pts. after irradiation with 60 GY (ICRU dose specification). Complete surgical exstirpation offers the best possibility of tumour control. Grade-III-tumours should be irradiated whatever the extent of the primary surgery was. Our results might indicate a possible indication for XRT in pts. with atypical grade-II-tumours especially when radical surgery must be in doubt. Prospective multicentre trials are warranted to prove the prognostic value of the new WHO-classification for atypical and anaplastic meningiomas and to define the ultimate role of radiotherapy in this setting.

Adult↗

PubMed1990

Truncus arteriosus revisited: an angiographic demonstration.

The 1965 reclassification of truncus arteriosus by Van Praagh and Van Praagh greatly enhanced our understanding of this interesting anomaly. This brief review article attempts to illustrate the various types of truncus arteriosus identified in this classification by demonstrating their angiographic features. Reemphasis of the usefulness of this classification should help students of congenital heart disease recognize the advantages of a uniform diagnostic approach to this entity.

Aorta, Thoracic↗

PubMed1991

Planimetric analysis of megakaryocytes in the four main groups of chronic myeloproliferative disorders.

Planimetry of megakaryocytes (MK) was performed in bone marrow biopsies (BMBs) from patients with chronic myeloproliferative disorders (CMPD) to substantiate cytomorphologic differences in this cell lineage between the four main groups of CMPD. The biopsy specimens were classified histologically prior to morphometry, according to the Hannover Classification of CMPD. Five histological groups were investigated, evaluating between 21 and 30 biopsies in each group. The five groups were as follows: (1) Chronic myelocytic leukemia (CML) of common type (CML.CT), (2) CML with megakaryocytic increase (CML.MI), (3) polycythemia vera (P. vera), (4) primary thrombocythemia (PTH), and (5) chronic megakaryocytic-granulocytic myelosis (CMGM). The results of five variables, i.e. the cellular and nuclear size, the cellular and nuclear form factor, and nuclear segmentation, were determined in at least 50 MK per BMB. The results reveal significant differences in MK nuclear and cellular size, as well as in nuclear segmentation between CML and the three other groups in that the nuclear and cellular size of the MK in CML are smaller than in P. vera, PTH, and CMGM. Moreover, the degree of nuclear segmentation or lobulation differs significantly between the three disorders characterized by large MK. Discriminant analysis permits 78-100% reliability of reclassification by morphometry compared with the histologic classification. A reduced reliability of the morphometric classification to around 80% was found between P. vera and PTH, as well as between P. vera and CMGM. In the design of this study, morphometry of MK lends added weight to the subjective classification of these disorders.

Biopsy↗

PubMed1982

Ultrastructural characterization of de novo and secondary leukemias.

Cells from 95 patients with acute leukemia were studied by cytochemistry, light microscopy, and transmission electron microscopy (TEM), and were classified according to the French-American-British (FAB) guidelines. This group included 63 patients with acute nonlymphocytic leukemia (ANLL) de novo, 18 with acute lymphocytic leukemia (ALL), and 14 with ANLL as a second malignancy. In addition, 13 cases of chronic myelocytic leukemia in blast crisis were studied. Ultrastructural examination resulted in reclassification of 6 cases of ANLL de novo; two of these were reclassified from M2 (myeloblastic leukemia with maturation) to M3 variant (microgranular variant of hypergranular promyelocytic leukemia). The classification of the cases of CML in blast crisis was identical by light microscopy and TEM. IN 1 case of myeloblastic crisis, however, basophilic granules were demonstrated by TEM but were not appreciated by light microscopy. Classification of the cases of secondary leukemia was possible by light microscopy and cytochemistry in all 14 cases, but was often difficult since the cytochemical reactions were usually less intense than in de novo ANLL. This was particularly true in those cases classified as M1, and in such cases, TEM was required to confirm the diagnosis.

Acute Disease↗

PubMed2005

Early diagnosis of pancreatobiliary duct malignancies by brush cytology and biopsy.

Two hundred and five preoperative intraductal samplings (brushing and biopsy) were evaluated from 113 patients with biliary or Wirsung duct strictures. One hundred and three strictures could be specified by histology of the operative specimens, autopsy, or by the patients' clinical course. Preoperative diagnostic efficacy depended on the tumor location (it was the best for ampullary and para-papillary tumors), but the average quantitative indices for sensitivity, absolute sensitivity, specificity, positive and negative predictive values, diagnostic accuracy of cytology were 53%, 20%, 100%, 100%, 25%, 59%, respectively. The same values for biopsy were 43%, 34%, 100%, 100%, 36% and 56%. These figures improved after simultaneous cytology and biopsy. Close cooperation with the endoscopist was necessary in cases of negative, inconclusive and dysplastic (27%) samples. Repetition of sampling improved the results by 8%. Among the 26 preoperative false negative cases, sampling-, technical- and interpretative errors occurred in 84%, 4% and 12%, respectively. Revision of samples revealed 4 malignant cases among the false negative cytologic brushings. Reclassification of specimens considering the latest criteria - primary and secondary malignant features, pancreatic intraepithelial neoplasia (PanINs), etc. - resulted in improvement of the diagnostic efficiency.

Bile Duct Neoplasms↗

PubMed2005

Ribotyping of Lactobacillus casei group strains isolated from dairy products.

A series of lactobacilli isolated from dairy products were characterized using biotyping and ribotyping with EcoRI and HindIII restriction enzymes. Biotyping assigned 14 strains as Lactobacillus casei, 6 strains as Lactobacillus paracasei subsp. paracasei and 12 as Lactobacillus rhamnosus. The obtained ribotype patterns separated all analyzed strains into two clearly distinguished groups corresponding to L. rhamnosus and L. casei/L. paracasei subsp. paracasei. The HindIII ribotypes of individual strains representing these two groups were visually very similar. In contrast, EcoRI ribotyping revealed high intraspecies variability. All ribotypes of L. casei and L. paracasei subsp. paracasei dairy strains were very close and some strains even shared identical ribotype profiles. The type strains L. casei CCM 7088T (= ATCC 393T) and Lactobacillus zeae CCM 7069T revealing similar ribopatterns formed a separate subcluster using both restriction enzymes. In contrast, the ribotype profile of L. casei CCM 7089 (= ATCC 334) was very close to ribopatterns obtained from the dairy strains. These results support synonymy of L. casei and L. paracasei species revealed by other studies as well as reclassification of the type strain L. casei CCM 7088T as L. zeae and designation of L. casei CCM 7089 as the neotype strain.

Dairy Products↗

PubMed1999

Care and feeding of a staff for filmless radiology.

Texas Children's Hospital, a definitive care pediatric hospital located in the Texas Medical Center, has been constructing a large-scale picture archival and communications system (PACS) including ultrasound (US), computed tomography (CT), magnetic resonance (MR), and computed radiography (CR). Developing staffing adequate to meet the demands of filmless radiology operations has been a continuous challenge. Overall guidance for the PACS effort is provided by a hospital-level PACS Committee, a department-level PACS Steering Committee, and an Operations Committee. Operational Subcommittees have been formed to address service-specific implementation, such as the Emergency Center Operations Subcommittee. These committees include membership by those affected by the change, as well as those effecting the change. Initially, personnel resources for PACS were provided through additional duties of existing imaging service personnel. As the PACS effort became more complex, full-time positions were created, including a PACS Coordinator, a PACS Analyst, and a Digital Imaging Assistant. Each position requires a job description, qualifications, and personnel development plans that are difficult to anticipate in an evolving PACS implementation. These positions have been augmented by temporary full-time assignments, position reclassifications, and cross-training of other imaging personnel. Imaging personnel are assisted by other hospital personnel from Biomedical Engineering and Information Services. Ultimately, the PACS staff grows to include all those who must operate the PACS equipment in the normal course of their duties. The effectiveness of the PACS staff is limited by their level of their expertise. This report discusses our methods to obtain training from outside our institution and to develop, conduct, and document standardized in-house training. We describe some of the products of this work, including policies and procedures, clinical competency criteria, PACS inservice topics, and an informal PACS newsletter. As the PACS system software and hardware changes, and as our implementation grows, these products must to be revised and training must be repeated.

Biomedical Engineering↗

PubMed2001

[DNA cytometric studies of Barrett mucosa].

BACKGROUND: Barrett's esophagus predisposes to cancer development. The diagnosis of dysplastic precursor lesions is impaired by problems of subjectivity. In the present study, DNA ploidy results of patients with Barrett's esophagus were related to the grade of dysplasia and to the progress of the disease. PATIENTS AND METHODS: In 61 patients with Barrett's esophagus, DNA ploidy was determined by image cytometry on imprints. All biopsies (n = 145) were histologically examined for dysplasia distinguishing between low- and high-grade dysplasia, and dysplasia-negative. RESULTS: A significant correlation (p < 0.001) between DNA ploidy and the grade of dysplasia was found, with 81% euploid DNA results in biopsies negative for dysplasia and 86% abnormal DNA patterns in biopsies with high-grade dysplasia. The subgroup of low-grade dysplasia showed a heterogeneous DNA ploidy. It is important to note that nearly 20% of biopsies classified dysplasia-negative contained abnormal single cells or abnormal stemlines regarding DNA content. In several cases, suspect DNA results caused a modified reclassification of dysplasia, and there were cases in which patients negative for dysplasia but positive for abnormal DNA ploidy developed dysplasia later on. CONCLUSION: In patients with Barrett's esophagus, DNA ploidy by image cytometry is a suitable additive method for histological evaluation of dysplasia. It seems to be helpful in identifying patients at risk, perhaps before the development of clear dysplasia.

Aneuploidy↗

PubMed1996

[Fungi of the Trichosporon genus. Identification, epidemiology and significance of dermatologic disease pictures].

Based on molecular data, the genus Trichosporon was recently reclassified. Six human pathogenic species, which are closely related to specific types of infections can be differentiated. By means of commercial test systems and simple key criteria according to Gueho et al. [15], 44 isolates that had been identified as Tr. cutaneum between 7/92 and 1/96, were reclassified. The evaluation of clinical data also included 66 isolates that had not been preserved, and 27 strains of Tr. inkin. Trichosporon species were found in 4.8% of all yeast isolates (3.8% Tr. cutaneum, 1% Tr. inkin). Nearly every other isolate of Tr. cutaneum was cultivated from nail material, while Tr. inkin was mainly isolated from skin in the anogenital region. In 38 cases, reclassification revealed Tr. mucoides; Tr. ovoides and Tr. asteroides were identified in 3 cases each, while Tr. asahii, an especially remarkable pathogen in systemic mycoses, was not found. Clinically, isolates of Tr. mucoides were predominant in toenail mycoses which might be considered in the therapy of onychomycosis. Furthermore, isolates from the skin should be evaluated with respect to the increasing incidence of systemic Trichopsoron mycoses.

Adolescent↗

PubMed2005

Genotype versus phenotype in the circumscription of bacterial species: the case of Pseudomonas stutzeri and Pseudomonas chloritidismutans.

The phenotypic characteristic of strain AW-1(T) of Pseudomonas chloritidismutans that is most relevant from the taxonomic point of view appears to be the capacity of growth under anaerobic conditions using chlorate as electron acceptor. This property is not restricted to this species only within the genus Pseudomonas, since it is also present in strains of genomovars 1 or 5, and 3 of Pseudomonas stutzeri. P. chloritidismutans has been described as a non-denitrifying species, but the isolation of variants that are able to grow anaerobically in the presence of nitrate is possible after subcultivation under selective conditions. The subdivision of P. stutzeri into a number of species on the basis of these characteristics does not help to clarify the phylogenetic relationships among the members of an otherwise coherent group of strains, and the considerations presented in this communication support the reclassification of the new species name P. chloritidismutans, which in our opinion, should be considered as a Junior name of P. stutzeri. A multilocus sequence analysis, together with a phenotypic analysis of the anaerobic oxidative metabolism, gives new insights into the phylogeny and evolution of the species.

Chlorates↗

PubMed2003

The alpha-actinin gene family: a revised classification.

The sequencing of a genome is the first stage of its complete characterization. Subsequent work seeks to utilize available sequence data to gain a better understanding of the genes which are found within a genome. Gene families comprise large portions of the genomes of higher vertebrates, and the available genomic data allow for a reappraisal of gene family evolution. This reappraisal will clarify relatedness within and between gene families. One such family, the alpha-actinin gene family, is part of the spectrin superfamily. There are four known loci, which encode alpha-actinins 1, 2, 3, and 4. Of the eight domains in alpha-actinin, the actin-binding domain is the most highly conserved. Here we present evidence gained through phylogenetic analyses of the highly conserved actin-binding domain that alpha-actinin 2 was the first of the four alpha-actinins to arise by gene duplication, followed by the divergence of alpha-actinin 3 and then alpha-actinins 1 and 4. Resolution of the gene tree for this gene family has allowed us to reclassify several alpha-actinins which were previously given names inconsistent with the most widely accepted nomenclature for this gene family. This reclassification clarifies previous discrepancies in the public databases as well as in the literature, thus eliminating confusion caused by continued misclassification of members of the alpha-actinin gene family. In addition, the topology found for this gene family undermines the 2R hypothesis theory of two rounds of genome duplication early in vertebrate evolution.

Actinin↗

PubMed2025

South African Myxococcota: an untapped resource for microbial ecolo gy and biotechnology.

An extraordinary multicellular life cycle, ecological versatility, and prolific production of bioactive secondary metabolites characterise the phylum Myxococcota. While research has predominantly focused on Myxococcota in Asia, Europe, and North America, their potential occurrence in Sub-Saharan Africa remains largely unexplored. To date, only one study has isolated Myxococcota in South Africa, with additional findings limited to incidental detection through metagenomic studies. Considering South Africa's ecological diversity, its biomes may represent promising but under-examined environments for systematic bioprospecting aimed at discovering novel Myxococcota with ecological or biotechnological potential. The recent reclassification of Myxococcota from the former Deltaproteobacteria has provided a more coherent taxonomic framework to guide future ecological and systematic studies. This review presents an overview of the taxonomic revision and explores the potential occurrence of Myxococcota in South African biomes. It covers the challenges associated with conventional culture-based isolation methods and highlights potential genome- and metagenome-based approaches, including the use of metagenome-assembled genomes (MAGs) to identify cryptic biosynthetic gene clusters (BGCs), while acknowledging current limitations. Considering the increasing resistance to chemical fungicides in South African agriculture, this review further explores the potential of Myxococcota-derived secondary metabolites as candidate bioprotective alternatives. By identifying current research gaps, it aims to support future efforts towards systematic bioprospecting to investigate the ecological and biotechnological potential of Myxococcota in South Africa. KEY POINTS: • South African biomes may harbour novel Myxococcota with biosynthetic potential. • Genome mining could reveal cryptic biosynthetic gene clusters (BGCs). • Myxococcota metabolites may help control resistant fungal phytopathogens.

South Africa↗