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At least 343 records · Page 19Linked to original sources
PubMedDate not supplied

Metastatic bacterial endophthalmitis: a contemporary reappraisal.

Metastatic bacterial endophthalmitis remains a challenge to the clinician despite the success of antibiotics in reducing its frequency and severity. Controversy currently surrounds the management of this condition because of uncertainty about the value of and indications for vitreous surgery. We review 72 cases of metastatic endophthalmitis from the past decade, including five not previously published. The spectrum of causative bacteria changed significantly during this period, with displacement of meningococcus by Bacillus cereus as the most frequently reported agent and an increasing incidence of infection by organisms of low pathogenicity in immunologically compromised hosts. We propose a new classification scheme for metastatic endophthalmitis based on the location (anterior or posterior segment) and extent (focal or diffuse) of the primary intraocular infection. Focal and anterior cases appear to have a good prognosis, while posterior diffuse disease nearly always leads to blindness. Our analysis of outcomes suggests that systemic antibiotics are more valuable in metastatic than in postoperative or traumatic endophthalmitis and that intraocular antibiotic injection and vitrectomy make only a limited contribution to successful treatment in metastatic infection. We recommend a clinical approach to metastatic endophthalmitis that minimizes exposure of patients to the risks of invasive procedures.

Adolescent↗
PubMed1984

Primary inoculation complex of skin by Mycobacterium chelonei.

We report a patient with a primary inoculation complex of the skin caused by Mycobacterium chelonei, a facultative pathogen that belongs to group IV of Runyon's classification of atypical mycobacteria. This organism is seldom responsible for disease in humans, although cutaneous, pulmonary, heart, bone, and disseminated infections have been reported. An unusual cutaneous manifestation of this organism is presented with a review of the literature.

Child↗
PubMed2004

Comparative analysis of different typing methods for Helicobacter pylori clinical isolates.

The goal of the present work was to compare different techniques of molecular typing using as an example clinical isolates of Helicobacter pylori obtained from patients in different regions of Russia. DNA-macroarray genome scanning using individual genes was employed to set up our basic classification of isolates that did or did not contain pathogenicity islands. In parallel, DNA of the same isolates was used in the conventional random amplified polymorphic DNA (RAPD) PCR analysis, and the isolates were also genotyped (cagA, vacA, iceA, and babA status) and their proteomic maps were obtained by means of unidimensional SDS polyacrylamide gel electrophoresis (1D-SDS-PAGE) coupled with identification using peptide mass fingerprinting by MALDI-TOF mass spectrometry. A statistically significant correlation (coefficient of correlation r = 0.25, p = 0.005) was observed between the results of genome scanning and 1D-SDS-PAGE. No correlation was found between RAPD-PCR typing and genome scanning.

Bacterial Typing Techniques↗
PubMed1990

Acute chagasic cardiopathy produced by a strain of Trypanosoma cruzi (type I) in an experimental model.

We have carried out a study of the tissular tropism of the strain Y of T. cruzi considering that the different strains of T. cruzi show a great instability in their pathogenic properties with the aim of proving that the classifications of his parasite based in its tissular tropism are not reliable given that these characteristics are subject to change as can be seen by comparing our results with those of other authors. In our study, the Y. strain of T. cruzi shows a strong pancytotropic action, specially with marked cardiotropic aspects. The lack of affectation in the lymphatic ganglion and the small proportion of spleen lesions (8%) as well as the absence of pseudocysts at this level is surprising in a strain which was described as eminently reticulotropic. Our data show that this strain produces cardiac pseudocysts without lesions of the parasitized muscle fiber. The above mentioned data evidence that the biological behavior of a strain and specially its tissular tropism are susceptible to present variations with time.

Acute Disease↗
PubMed2026

Mast cell leukemia with complex genomic alterations in an elderly patient with prior hematologic and solid malignancies: a case report.

INTRODUCTION: Mast cell leukemia (MCL) is the rarest and most aggressive variant of systemic mastocytosis (approximately 1% of cases), with a median survival of under 2 years. Diagnosis requires ≥20% atypical mast cells in the marrow aspirate, and the disease frequently overlaps with myeloid neoplasms. CASE PRESENTATION: An 86-year-old man with paranasal sinus diffuse large B-cell lymphoma in remission since 2017 after R-CHOP and methotrexate, and prostate adenocarcinoma treated in 2019, presented with acute pancytopenia, presumed to represent lymphoma relapse. Serum tryptase exceeded 11 999 ng/mL; the aspirate showed 20% pleomorphic mast cells (CD117+, weak CD25, CD2-), confirming aleukemic MCL. Formal CMML criteria could not be confirmed due to the unavailability of monocyte differential data; however, the findings raised suspicion for an associated myeloid neoplasm, with SM with an associated hematological neoplasm remaining an alternative classification. Karyotyping was normal; next-generation sequencing revealed pathogenic variants in TP53, RB1, DAXX, ASXL1, TET2, and SRSF2, and a rare extracellular-domain KIT p.D419del. He declined inpatient midostaurin, deteriorated rapidly, and died 2 weeks later. CLINICAL DISCUSSION: This case illustrates a therapy-related MCL (plausible but unconfirmed given the non-leukemogenic profile of methotrexate and the focal nature of prostate stereotactic body radiation therapy) with a suspected associated myeloid neoplasm and complex pathogenic mutations. The KIT p.D419del extracellular domain variant is a rare non-D816V mutation; the canonical D816V was not detected on NGS, though the presence of a low-variant allele fraction D816V cannot be fully excluded due to assay sensitivity. Despite midostaurin, the disease remained aggressive. CONCLUSION: Persistent unexplained cytopenias warrant heightened suspicion of MCL, and comprehensive genomic profiling clarifies diagnosis, distinguishes overlapping myeloid disease, and informs prognosis in this aggressive, refractory neoplasm.

case report↗
PubMedDate not supplied

[Characterization of Yersinia pseudotuberculosis heat stable serovar specific polypeptides with the use of monoclonal antibodies].

The capacity of Y. pseudotuberculosis to express serovar specific polypeptides with different specificity of antigenic determinants was proved with the use of monoclonal antibodies (McAb). For the first time Y. pseudotuberculosis O antigens were found to have heat stable protein components carrying linear epitopes complementary to serovar specific MaAb and ensuring the serological specificity of the infective agent. The possibility of improving intraspecific classification of Y. pseudotuberculosis and their differentiation from other pathogenic Yersinia on the basis of the capacity of these bacteria for synthesizing species and serovar specific proteins is substantiated.

Animals↗
PubMed1987

[Significance of Yersinia enterocolitica and thermophilic Campylobacter for water hygiene].

The taxonomy of Yersinia enterocolitica as well as their classification methods are still unreliable with respect to their pathogenicity. Therefore, a basis of evaluation was established by using extended biochemical tests (API-20-E, API-50-CH) and electrophoretic methods for identifying strains from human, food and water sources. All strains show great inhomogenicity, which was higher for non-human strains than for those isolated from clinical specimens. Thermophilic Campylobacters are especially prevalent in wild living fowl thus being a potential risk for surface water contamination. The results of the study show that high colony counts were found only during winter, whereas in summer the concentration lay below the infective dose. Furthermore, thermophilic Campylobacters were isolated only from samples that contained a higher number of fecal indicator organisms.

Bacteriological Techniques↗
PubMed1993

Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus. Diseases of autoimmunity to type VII collagen.

Autoimmunity to C7 is a genetically predisposed condition that results in the production of predominantly IgG class basement membrane autoantibodies that may cause basement membrane damage and subepidermal blisters by at least two pathogenic mechanisms. Autoimmunity to C7 cuts across traditional disease classifications (EBA versus bullous SLE), presents with heterogeneous clinical and pathologic features, mimics other diseases, and may be difficult to diagnose and treat. Autoimmunity to C7 is associated with susceptibility to SLE and perhaps inflammatory bowel disease.

Autoantibodies↗
PubMed1997

Classification of Vibrio vulnificus strains by the carbohydrate composition of their capsular polysaccharides.

Pathogenic bacteria are often classified on the basis of the complex polysaccharides found on the surface, usually capsular polysaccharides or lipopolysaccharides. It is common in clinical practice to use reactivity with antisera specific to the various cell surface carbohydrates for this purpose. In this work, we describe a chemotyping method for bacterial capsular polysaccharides which is based on a carbohydrate analysis of an acid hydrolysate of the capsule. High-performance anion-exchange chromatography at high pH (HPAE) with electrochemical detection, which is used for analysis of the hydrolysate, shows preferential sensitivity for sugars. A single acid hydrolysis condition is chosen for screening a large collection of bacterial isolates and a computerized autosampler is used to make possible a large number of rapid analyses. This procedure does not yield a quantitative carbohydrate analysis for the sample but produces a fingerprint which can be used to discriminate among isolates which have different capsular polysaccharide structures. The procedure has been applied to a collection of 120 isolates of Vibrio vulnificus, a water-born species common in shellfish which causes septicemia in immunocompromised individuals, most often from eating of raw oysters. The collection of bacterial isolates includes strains from both clinical cases of septicemia and from such environmental sources such as sea water, sediments, and shellfish. Our results show that a number of unusual sugars including many amino sugars are found in these polysaccharides and that a wide variety of capsular carbotypes in V. vulnificus may be readily distinguished by the HPAE fingerprint.

Anion Exchange Resins↗
PubMed2002

Schizophrenia and bipolar disorder: similarities in pathogenic mechanisms but differences in neurodevelopment.

Over the past 100 years, the Kraepelinian classification of psychoses has dominated our approach to schizophrenia and bipolar disorder. However, controversy as to the nature of the illnesses--whether they can be viewed as completely distinct, essentially the same, or occupying different points along a psychosis spectrum--has intensified in recent years. This paper reviews the evidence for these differing opinions, examining both the commonalities between the two diseases and the distinctions. A genetic propensity towards psychotic disorders is widely acknowledged; more recent studies suggest a considerable overlap in genetic susceptibility to schizophrenia and bipolar disorder. The influence of early environmental effects, such as obstetric complications, on schizophrenia is also established but little such evidence exists for bipolar disorder. Structural abnormalities of the brain of developmental origin as well as neuropsychological deficits have been clearly identified in schizophrenia but less evidence has been found in bipolar disorder. The most plausible explanation is that one or more susceptible genes are shared between schizophrenia and bipolar illness, and can be thought of as predisposing individuals to psychosis, perhaps by producing a dysregulation of the dopaminergic response to stress. Other genes and environmental factors are likely to have more specific effects and contribute to producing the patterns that psychiatrists recognize as 'classical' schizophrenia and mania. In particular, genes involved in early cortical development and early neurodevelopmental insults causing developmental impairment may put individuals on a trajectory towards schizophrenia rather than bipolar illness.

Adult↗
PubMed2006

Effect of selective growth media on the differentiation of Salmonella enterica serovars by Fourier-Transform Mid-Infrared Spectroscopy.

Salmonella enterica serovars are prevalent foodborne pathogens responsible for high numbers of salmonellosis each year. Complex Fourier-transform infrared (FTIR) spectra offer unique biochemical fingerprints of bacteria with bands due to major cellular components. Growth media effects on discrimination of Salmonella serovars by FTIR spectroscopy were investigated and a novel sample preparation technique was developed. S. enterica strains from six serovars were grown on xylose lysine desoxycholate (XLD), Miller-Mallinson (MM), and plate count (PCA) agar as a control (37 degrees C, 24 h). Isolated colonies were suspended in 50% acetonitrile and centrifuged; the remaining pellet was placed on an AMTIR (attenuated total reflectance) crystal and dried under vacuum. Classification models (Soft Independent Modeling of Class Analogy, SIMCA), generated from derivatized infrared spectra (1300-900 cm-1 or 1200-900 cm-1), successfully discriminated among Salmonella strains with major discrimination from 1000-970 cm-1 associated to stretching modes of O-specific polysaccharide chains of lipopolysaccharides. Sample treatment with acetonitrile enhanced safe handling of the bacteria, removed interfering signals and improved the discriminating ability of SIMCA. All media were able to discriminate the S. enterica strains studied, varying in discriminating peaks and class distances in SIMCA classification. This methodology, with the production of large libraries of pathogenic bacteria, could be applied for the rapid monitoring of bacterial contamination in food with minimal sample manipulation.

Agar↗
PubMed2025

Imprecision medicine: Systematic gaps in reporting variants of uncertain significance (VUS) and their reclassifications.

PURPOSE: Variants of uncertain significance (VUS) are frequently encountered during clinical genetic testing. To explore the clinical burden of VUS, we developed the Brotman Baty Institute Clinical Variant Database, which is an electronic health record (EHR)-linked database of clinical germline genetic variant information from patients with rare genetic disorders seen at 2 tertiary academic medical centers. METHODS: We retrospectively reviewed EHRs and genetic testing reports from 5158 patients seen across diverse adult genetics practices at these institutions from 2015 to 2024. We also compared these EHR-based variant classifications with those in ClinVar. RESULTS: The number of reported VUS relative to pathogenic or likely pathogenic variants can vary by over 14-fold depending on the primary indication for genetic testing and 3-fold depending on self-reported race. Furthermore, at least 1.6% of variant classifications used in the EHR for clinical care are outdated based on ClinVar variant classifications, including 26 instances in which the testing lab updated ClinVar, but the reclassification was never communicated to the patient. CONCLUSION: Our findings reveal that the clinical burden of VUS in adult medical genetics is unequally distributed across patients. We also highlight a deficiency in existing systems for communicating variant reclassifications to ClinVar, patients, and providers.

Humans↗
PubMed1991

Lupus nephritis. Part II. A clinicopathological correlation and study of outcome.

A 5-year retrospective study of lupus nephritis at Tygerberg Hospital was performed in an attempt to document the clinical and histological spectrum of the disease and to study the outcome of the illness. Activity and chronicity scores were used in addition to the World Health Organisation classification system. Of 55 biopsies from 51 patients reviewed, 6 were class II, 13 class III, 32 class IV and 4 class V. There were 19 deaths and in 15 of these the histological classification was IV. Renal failure and infections, often with uncommon pathogens, were the most important causes of death. Serum creatinine values and creatinine clearance at the time of biopsy or follow-up, and hypertension at follow-up showed a significant relationship with outcome. WHO class IV was associated with a poor outcome (P = 0.048) when compared with the other WHO classes combined. Activity scores showed a significant relationship to the outcome (P = 0.018). The anticardiolipin antibodies IgG and IgM were not associated with WHO class or outcome. The study revealed a spectrum of histological results similar to that of other studies, with a high mortality rate, particularly in class IV disease. Poor renal function, persistent hypertension, histological classification IV, and high activity scores were found to be important prognostic indicators.

Adolescent↗
PubMed2003

[Molecular biological analysis of Tinea faciei caused by a clinically anomalous strain of Trichophyton mentagrophytes].

We report a case of Trichophyton mentagrophytes infection. A 27-year-old female dairy worker visited our hospital in August 2001 for evaluation of an erythematous lesion near her right eye. The patient had been treated with antibiotics and an anti-allergic drug at another clinic with no effect on the lesion. KOH preparation of the scale revealed mycelia and T. mentagrophytes was isolated from the culture. The isolated pathogen was identified as T. mentagrophytes animal type 1 by the classification system based on the cluster analysis of nuclear ribosomal internal transcribed spacer 1 (ITS1) DNA sequences. The oral administration of terbinafine at 125 mg/day and antifungal cream was effective. T. mentagrophytes is one of the most common dermatophytes isolated from humans and animals. We should be aware that animals may carry this kind of fungal pathogen.

Administration, Oral↗
PubMed1995

[The importance of classifications in psychiatry].

The classifications currently used in psychiatry have different aims: to facilitate communication between researchers and clinicians at national and international levels through the use of a common language, or at least a clearly and precisely defined nomenclature; to provide a nosographical reference system which can be used in practice (diagnosis, prognosis, treatment); to optimize research by ensuring that sample cases are as homogeneous as possible; to facilitate statistical records for public health institutions. A classification is of practical interest only if it is reliable, valid and acceptable to all potential users. In recent decades, there has been a considerable systematic and coordinated effort to improve the methodological approach to classification and categorization in the field of psychiatry, including attempts to create operational definitions, field trials of inter-assessor reliability, attempts to validate the selected nosological categories by analysis of correlation between progression, treatment response, family history and additional examinations. The introduction of glossaries, and particularly of diagnostic criteria, marked a decisive step in this new approach. The key problem remains that of the validity of diagnostic criteria. Ideally, these should be based on demonstrable etiologic or pathogenic data, but such information is rarely available in psychiatry. Current classifications rely on the use of extremely diverse elements in differing degrees: descriptive criteria, evolutive criteria, etiopathogenic criteria, psychopathogenic criteria, etc. Certain syndrome-based classifications such as DSM III and its successors aim to be atheoretical and pragmatic. Others, such as ICD-10, while more eclectic than the different versions of DSM, follow suit by abandoning the terms "disease" and "illness" in favor of the more consensual "disorder". The legitimacy of classifications in the field of psychiatry has been fiercely contested, being variously dubbed "a reductive academic exercise of no relevance to patients", "a dehumanizing labelling system, and a potential source of social and political violence", "a destructive prognostic guide", and so on. Other critics point to various aspects of certain classifications: the abandonment of theoretical concepts, the arbitrary nature of certain categories, the selection of definitions and criteria, the privileged position systematically accorded to the notion of category over that of general dimension. Multiaxial systems such as those proposed in successive versions of DSM or the classifications used in child psychiatry go some way towards meeting these criticisms. They go beyond simple labelling and place the patient in an overall medicopsycho-social setting. Nosographical indicators do not constitute an obstacle to psychopathological understanding. No classifications are capable of satisfactorily fulfilling all needs, namely those of daily practice, research and health statistics. The has led to the development of specialized diagnostic criteria and instruments, as in research for example. It should also be noted in this context that different versions of ICD-10 exist for psychiatrists, general practitioners, researchers and healthcare managers. The greatest danger posed by classifications is the potential reification of hypothetical approaches, arbitrary categorization and the dulling of reflection, all of which have created a need for regular revisions underpinned by field trials.

Humans↗
PubMed1986

Classification of Histoplasma capsulatum isolates by restriction fragment polymorphisms.

Twenty isolates of the dimorphic, pathogenic fungus Histoplasma capsulatum were divided into three classes based on comparisons of restriction enzyme digests of their mitochondrial DNA and rDNA. The majority of isolates, including most North American strains and the African H. capsulatum var. duboisii variants, belong to class 2. Isolates from Central America and South America make up class 3. The attenuated Downs strain is the only member of class 1.

Africa↗
PubMed2003

Analysis and functional classification of transcripts from the nematode Meloidogyne incognita.

BACKGROUND: Plant parasitic nematodes are major pathogens of most crops. Molecular characterization of these species as well as the development of new techniques for control can benefit from genomic approaches. As an entrée to characterizing plant parasitic nematode genomes, we analyzed 5,700 expressed sequence tags (ESTs) from second-stage larvae (L2) of the root-knot nematode Meloidogyne incognita. RESULTS: From these, 1,625 EST clusters were formed and classified by function using the Gene Ontology (GO) hierarchy and the Kyoto KEGG database. L2 larvae, which represent the infective stage of the life cycle before plant invasion, express a diverse array of ligand-binding proteins and abundant cytoskeletal proteins. L2 are structurally similar to Caenorhabditis elegans dauer larva and the presence of transcripts encoding glyoxylate pathway enzymes in the M. incognita clusters suggests that root-knot nematode larvae metabolize lipid stores while in search of a host. Homology to other species was observed in 79% of translated cluster sequences, with the C. elegans genome providing more information than any other source. In addition to identifying putative nematode-specific and Tylenchida-specific genes, sequencing revealed previously uncharacterized horizontal gene transfer candidates in Meloidogyne with high identity to rhizobacterial genes including homologs of nodL acetyltransferase and novel cellulases. CONCLUSIONS: With sequencing from plant parasitic nematodes accelerating, the approaches to transcript characterization described here can be applied to more extensive datasets and also provide a foundation for more complex genome analyses.

Animals↗