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At least 181 records · Page 10Linked to original sources
PubMed2026

RNA splicing evidence enables robust classification of BRCA1 exon 18 variants: Results from the ENIGMA consortium.

The Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) research consortium conducted a comprehensive study to characterize spliceogenic variants in BRCA1 exon 18. The absence of systematic RNA-based assessment for these variants has led to inconsistent interpretation, limiting accurate classification and management of individuals and their families. The splicing profile of 166 variants was assessed using minigene assays; 32 were additionally analyzed in blood-derived RNA from 51 individuals and 18 in mouse embryonic stem cell (mESC)-based assays to evaluate homology-directed repair (HDR) capacity. mRNA assessment by RT-PCR in blood samples and minigene assays showed a significant positive correlation, with splicing analysis in mESCs displaying highly concordant results. The mESC-based HDR assay showed that the in-frame exon 18 skipping (&#x394;18) transcript encodes a non-functional protein lacking rescue activity. Linear regression analysis using mESC splicing and functional data indicated that &#x2265;59% of full-length (FL) levels and <34% of &#x394;18 were associated with benign HDR activity. These thresholds differ from those recommended by the ClinGen ENIGMA BRCA1 and BRCA2 Variant Curation Expert Panel American College of Medical Genetics and Genomics (ACMG)/Association for Molecular Pathology (AMP) specifications for applying BP7_strong(RNA): >30% functional transcripts or <70% non-functional transcripts. Incorporation of RNA splicing evidence into variant interpretation increased pathogenic (28.6%-31.7%) and benign (3.7%-24.4%) classifications while reducing likely pathogenic (19.5%-17.7%), uncertain (18.9%-8.5%), and likely benign (29.3%-17.7%) categories. Experimental mRNA profiling impacted the interpretation of 34% of variants and resolved uncertainty in approximately 10% of cases. Exon 18 skipping was less tolerated, indicating that the degree of splice perturbation required to impair BRCA1 function may depend on the nature of the resulting non-functional transcript.

Humans↗
PubMed1997

Identification of pathogenic yeasts of the imperfect genus Candida by polymerase chain reaction fingerprinting.

With the increase in the number of immunocompromised hosts, the number of fungal pathogens has increased markedly. Identification and classification, especially of yeast species and strains, is often difficult when based solely on phenotypic characteristics. Since it became clear that different fungal pathogens require specific treatment strategies, there is a need for simple, rapid and reliable methods to identify fungal isolates. Polymerase chain reaction (PCR) fingerprinting was successfully applied here to identify yeast isolates. Microsatellite [(GTG)5; (GACA)4] and minisatellite [(5'GAGGGTGGCGGTTCT 3'), derived from the core-sequence of the phage M13] specific primers were used as single primers in the PCR to amplify hypervariable interrepeat DNA sequences from over 200 European, American and Australian clinical isolates within the genus Candida. Each species, represented by its type strain, could be identified by a specific multilocus pattern, allowing for the assignment of all the isolates to the appropriate species. Intra-species variation in the multilocus profiles was about 20% compared to inter-species variation, which was up to 80%. Anamorph-teleomorph pairs could be identified by highly homologous PCR fingerprint patterns. PCR fingerprinting was more discriminatory when compared with routinely used biochemical tests (Vitek YBC and API ID 32C). PCR fingerprinting has proven to be a powerful tool for the identification of medically important yeasts. It is rapid, sensitive, reliable, highly reproducible, stable in vitro and in vivo, and applicable to large scale experiments. Potential applications include: yeast taxonomy, epidemiology, environmental surveys, and improvement of the diagnosis of mycotic diseases.

Australia↗
PubMedDate not supplied

[A proposed classification of swollen legs].

The subject of enlarged legs is vast and complex. Up to now there has been no organic classification of the clinical picture involved. The basic problem is that of the criterion on which to base the classification. Literature on this subject has opted for the pathogenic criterion because it seems to facilitate the formulation of a classification which is of use to the doctor. One possibility would be to divide the syndrome into vascular and non-vascular swollen legs. The first group could in turn be separated into macro-circulating and micro-circulatory. The micro-circulatory forms can be primitive or secondary. Amongst the secondary micro-circulatory forms, two other groups can be singled out: secondary forms with local cause and secondary forms caused by organic pathology. However, there are clinical forms which are on the periphery of these different groups and these forms are subject to discussion regarding nosographic localization.

Edema↗
PubMed1990

The detection of genetic variation in Leptospira interrogans serogroup ICTEROHAEMORRHAGIAE by ribosomal RNA gene restriction fragment patterns.

Deoxyribonucleic acid from Leptospira interrogans serogroup ICTEROHAEMORRHAGIAE reference strains together with clinical and animal isolates were cleaved with EcoRI, electrophoresed and transferred to nylon membranes. An Escherichia coli MRE 600, 16S + 23S ribosomal RNA template was used in the synthesis of a single strand biotin-labelled cDNA probe using a reverse transcriptase. Ribosomal RNA cistrons present in the DNA fragments of strains were located using the cDNA probe. Between 4 and 7 well defined ribosomal RNA restriction bands were detected for the leptospires studied that varied in size from 12.1 to 0.57 kb. The hybridisation patterns were distinctive and unique for the reference strains that allowed for their characterisation. Similar patterns were observed for I. budapest M 20, I. "icterohaemorrhagiae" Ictero I and the type strain, I. icterohaemorrhagiae RGA. Clinical isolates and a isolate from a rat were compared with reference strain DNA patterns and identified as being similar to I. copenhageni M 20, I. "icterohaemorrhagiae" Ictero I and I. icterohaemorrhagiae RGA. These results indicate that ribosomal DNA fingerprinting may be useful in the classification and molecular epidemiology of pathogenic leptospires.

DNA Probes↗
PubMedDate not supplied

Nasal fossa malformations and paramedian facial cleft: new perspectives.

Choanal atresia may be associated with other cranio-facial malformations, including various degrees of nasal fossa malformation, and may be a part of paramedian facial clefts (as described by Tessier et al. [1977]). We identified five such cases with combined clinical elements corresponding to Tessier's paramedian facial cleft, including eyelid coloboma, mild to severe choanal and nasal fossa anomalies, ethmoidal hypoplasia and anterior skull base malformation, sometimes with proboscis lateralis and half-nose hypoplasia. These observations incited us, first, to elaborate a conception which accounts for the likely embryological mechanisms involved; second, to propose a new classification based on anatomical and pathogenic embryological considerations; and last, to propose the use of transpalatal approach to restore choanal permeability, since endonasal laser therapy is particularly dangerous in such cases.

Child, Preschool↗
PubMed2000

The neuropathology of multiple sclerosis.

This article reviews the pathology of multiple sclerosis in an attempt to allow the reader to better understand the pathogenesis of the lesions. The elements comprising the lesions are discussed in light of their pathogenic implications. Current ideas of classification are discussed, and wherever possible, correlations with clinical and imaging studies are drawn.

Animals↗
PubMed2003

[Animal pathogens as biological weapons].

In this article, the most important animal pathogens, which, according to CDC classification, can be used as biological agents, are presented. The means of dissemination and the ways of infection's propagation are reviewed. Typical and the most dangerous signs and symptoms are described, as well as the consequences of these infections.

Animal Population Groups↗
PubMed1978

[Effectiveness of antibiotics in bovine staphylococcal and streptococcal mastitis].

The present knowledge of the efficiency of antibiotics against bovine mastitis has been reviewed. Criteria for the choice of papers are given, together with tabulated results of treatments with one antibiotic or two. Results are discussed in relation to the time of treatment and the pathogenic agent involved, and a classification of the antibiotics into three groups is proposed: recommended; not advised; not sufficiently studied.

Animals↗
PubMed1977

[Bioptic investigations of the nervous system (author's transl)].

Bioptic investigation of nervous tissue can be made by taking tissue samples of nerves, skin, muscle, rectum, dental pulp and brain. The choice of site for the biopsy depends on the results of previous clinical neurological, neurophysiological and biochemical investigations. Indications are: unexplained peripheral neuropathies, progressive degenerative diseases of the central nervous system and enzymopathies which are principally manifest in the nervous system (neurometabolic diseases). The result of a nerve tissue biopsy usually only leads to classification in a disease group (pathogenic unit) which only becomes diagnostically relevant in conjunction with the clinical data. In biopsies of the brain a virological examination should always be performed in addition to the morphological (light and electron microscopic) and biochemical investigation.

Adult↗
PubMed1995

[Persistent diarrhea in HIV infected patients: role of Enterocytozoon bieneusi].

OBJECTIVES: To determine the epidemiologic, clinical and aetiologic features of chronic diarrhoea in patients with human immunodeficiency virus (HIV) infection. METHODS: Between January 1992 and April 1993, all HIV positive patients with chronic diarrhoea were enrolled in a prospective study. There were 46 patients in the study group including 33 (22 homosexuals) in stage C according to the 1993 Centers for Disease Control classification. RESULTS: Thirty-four pathogenic agents were isolated in 26 of the patients (57%). Enterocytozoon bieneusi was the most frequently found pathogen (11 patients, 24%) followed by Cryptosporidium sp (8 patients). Enterocytozoon bieneusi was found in association with other pathogens in 7 patients. All patients with microsporidiosis were in stage C (p = 0.04) and had a longer duration of diarrhoea (19.6 vs 9.8 weeks, p = 0.03), greater weight loss (9.6 vs 2.1 kg, p = 0.0003) and a lower Karnofsky index (48% vs 67%, p = 0.01). Prophylaxy with dapsone or pyrimethamine during the 3 months prior to inclusion had been more frequent (p = 0.04 and p = 0.05 respectively) in patients without microsporidiosis. CONCLUSION: Microsporidiosis should be suspected as a probable cause of chronic diarrhoea in HIV positive patients with a CD4 count < 100/mm3. Multiple infections may be a factor leading to treatment failure. Microsporidiosis seems to be linked to homosexual intercourse.

AIDS-Related Opportunistic Infections↗
PubMed1996

Randomly amplified polymorphic DNA polymerase chain reaction assay for molecular epidemiologic investigation of Pasteurella pneumotropica in laboratory rodent colonies.

After an episode of clinical Pasteurella pneumotropica infection was diagnosed in a C57BL/6N mouse, a randomly amplified polymorphic DNA polymerase chain reaction assay (RAPD-PCR) was developed and used to genetically characterize and differentiate 52 field isolates and laboratory reference strains of P. pneumotropica and related bacteria. A survey of rodents in the facility recovered 36 isolates of P. pneumotropica from 30 mice, six isolates from hamsters, and three isolates from rats during the follow-up investigation. Antibiograms and routine bacteriologic evaluations for morphologic and biochemical characteristics on selective media did not substantively aid in the differentiation of these isolates, but the RAPD-PCR revealed four strains of P. pneumotropica in the colony, two of which were confined to rats and hamsters. The RAPD-PCR unambiguously differentiated Heyl and Jawetz biotypes of P. pneumotropica recovered from mice, identified two additional genetic groups for rat and hamster isolates, and clearly distinguished P. pneumotropica from related bacteria. Most field isolates were genetically consistent with the Jawetz biotype of P. pneumotropica. The RAPD-PCR is a fast, sensitive, and efficient method for identifying genetic differences between strains of the P. pneumotropica complex and can contribute substantially in addressing the epidemiology, pathogenesis, and taxonomic classification of this common opportunistic pathogen.

Animals↗
PubMed1996

[Malformations of the nasal fossa and paramedian facial clefts. New perspectives].

Since choanal atresia may be associated with other cranio-facial malformations, including various degrees of nasal fossa malformation, and be a part of paramedian facial clefts, (as described by Tessier), they can be integrated into the larger group of neurocristopathies. We identified four such cases with combined clinical elements corresponding to Tessier's paramedian facial cleft, including eyelid coloboma, mild to severe choanal and nasal fossa anomalies, ethmoidal hypoplasia and anterior skull base malformation, sometimes with proboscis lateralis. These various malformations are due to abnormality of the olfactive placode and the adjacent mesenchyme. These discoveries incited us to elaborate a conception first of all on the pertinent embryology involved, second, to propose a new classification based on anatomical and pathogenic embryological considerations. And finally, since endonasal laser therapy is particularly dangerous in such cases, to propose the use of transpalatal approach to restore choanal permeability. Pediatric ENT surgeons should pay special attention to any small stigmatism of facial cleft when dealing with children affected by choanal atresia.

Abnormalities, Multiple↗
PubMedDate not supplied

[Tympanosclerosis. I: proposed anatomical-surgical classification].

Tyrnpanosclerosis continues to be a clinically and pathogenically controversial topic. The options for dealing with it range from a conservative approach using hearing aids to surgery. With a view to justifying our therapeutic criteria, 29 cases of tympanosclerosis, out of a total of 200 surgical operations for otorrhea, were reviewed. An anatormical-surgical classification was established for use in approaching specific therapy for each particular case.

Cerebrospinal Fluid Otorrhea↗