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PubMed1989

Endometritis in the mare: A comparison between reproductive history and uterine biopsy as techniques for predicting susceptibility of mares to uterine infection.

Thirty mares with no clinical signs of endometritis were categorized as being susceptible or resistant to uterine infection depending on whether or not they had a history of recurrent endometritis. The same mares were then independently classified as susceptible or resistant on the basis of their uterine biopsies; those with significant endometrial degeneration were considered to be susceptible to endometritis. The mares then received an intrauterine inoculation of pathogenic Streptococcus zooepidemicus . Those mares which eliminated bacteria by 10 d after inoculation were considered truly resistant to endometritis, whereas those still infected at 10 d were considered susceptible. The original classifications based on history or biopsy were compared to the inoculation results. A history of recurrent endometritis provided a more sensitive (0.90) and specific (0.95) indication of susceptibility to uterine infection than a uterine biopsy with significant endometrial degeneration (sensitivity 0.5, specificity 0.75).

Journal Article↗
PubMed2025

Clinical and genetic variant re-analysis among pediatric probands undergoing genetic testing for arrhythmia syndromes.

BACKGROUND: Despite increases in genetic testing, longitudinal data regarding changes in diagnostic yield and variant reclassification for inherited arrhythmia syndromes are limited. OBJECTIVE: Determine longitudinal changes in diagnostic yield and variant classification. METHODS: Single-center retrospective study of probands <18 years undergoing genetic testing for suspected inherited cardiac conditions associated with arrhythmias, 2007 to 2018. Variants were classified as diagnostic (pathogenic/likely pathogenic), non-diagnostic (benign/likely benign [B/LB]), or variants of uncertain significance (VUS). Variant reclassification was performed in October 2023 using VarSome and American College of Medical Genetics criteria. We evaluated results by era (early 2007-2013 vs. later 2014-2018, coinciding with Sanger and next-generation sequencing, respectively) and by likelihood of disease based on clinical evaluation. RESULTS: Of 306 probands, initial testing was 23.2% diagnostic, 55.6% non-diagnostic (33.7% no variant, 21.9% B/LB), and 21.2% VUS. When comparing eras, diagnostic yield decreased (34.1%-15.3%), VUS increased (9.3%-29.9%), and non-diagnostic remained similar (55% to 57%). Variants for 22.7% (46/203) of probands with &#x2265;1 variant changed: 9.9% of diagnostic variants (7/71) downgraded to VUS or non-diagnostic, and 60.0% of VUS changed (23.1% upgraded, 36.9% downgraded). B/LB variants did not change. Probands with higher disease likelihood had 6-times the odds of diagnostic results compared to lower disease likelihood, regardless of era (odds ratio 6.3, 95% confidence interval 3.2-12.4, P < .0001). CONCLUSION: Variant reclassification led to changes in 23% of probands, both downgrading and upgrading status, even among probands initially thought to be pathogenic. When comparing later to earlier eras, VUS variants increased while diagnostic yield decreased. Findings support the need for variant re-interpretation and periodic reclassification over time.

Humans↗
PubMed2004

Complicated infections of skin and skin structures: when the infection is more than skin deep.

Skin and skin-structure infections are common, and range from minor pyodermas to severe necrotizing infections. Complicated infections are defined as involving abnormal skin or wounds, occurring in compromised hosts, or requiring surgical intervention. Classification schemes for these infections are varied and confusing. Distinguishing characteristics include the aetiological agent(s), clinical context and findings, depth of tissue involvement and rate of progression. The most common pathogens are aerobic Gram-positive cocci, but complicated infections frequently involve Gram-negative bacilli and anaerobic bacteria. Initial antibiotic therapy is usually empirical, and later modified by the results of stains and cultures of wound specimens. Broad-spectrum coverage is frequently needed for complicated infections. Ertapenem is a once-a-day parenteral Group 1 carbapenem antibiotic, recently licensed in the USA and Europe, which may assume an important role in treating some complicated skin and skin-structure infections. Surgical debridement is important for many complicated infections, and is the critical element in managing necrotizing fasciitis and myonecrosis.

Adult↗
PubMed2001

Von Hippel-Lindau disease: gene to bedside.

Von Hippel-Lindau is an autosomal dominant familial tumor syndrome with a risk of developing central nervous system and retinal hemangioblastomas, kidney cysts and clear cell carcinoma, cyst adenomas of other organs and pheochromocytoma. Despite continued elaboration of the neurobiologic role of the von Hippel-Lindau protein, the mainstay of management remains the definitive clinical diagnosis of von Hippel-Lindau syndrome (as distinct from sporadic cases of single von Hippel-Lindau-associated tumors), clinical monitoring and preemptive intervention by surgical or ablative therapy. Specific pharmacologic treatment awaits further biologic understanding of critical pathogenic components. Increasingly sensitive imaging and surgical techniques allow for optimum clinical management and intervention. This article will review von Hippel-Lindau molecular genetics, genotype-phenotype correlations and clinical classification, current understanding of the biology of the von Hippel-Lindau protein, its role in the pathophysiology of this disorder and the consequent implications for future therapeutic/interventional strategies. Central nervous system manifestations will be highlighted.

Brain Neoplasms↗
PubMed1997

Restriction endonuclease analysis of mitochondrial DNA of Acanthamoeba sp. YM-4 (Korean isolate).

Acanthamoeba sp. YM-4 is similar to A. culbertsoni based upon morphological characteristics of trophozoites and cysts. However, based on other characteristics, pathogenicity to mice, in vitro cytotoxicity and isoenzyme patterns. Acanthamoeba sp. YM-4 was quite different from A. culbertsoni. Restriction fragment length polymorphism (RFLP) analysis of mtDNA is useful in the classification of members belonging to the genus Acanthamoeba. Therefore, in this study, RFLP analysis of Acanthamoeba mtDNAs was accomplished using five restriction enzymes: HaeIII, HindIII, ClaI, PvuII and SalI. Each restriction enzyme produced approximately 3-15 fragments (range: from 0.6 kbp to 34.4 kbp). The mtDNA genome size, calculated by the summation of restriction fragments, averaged 46.4 kbp in Acanthamoeba sp. YM-4, 48.3 kbp in A. culbertsoni and 48.8 kbp in A. polyphaga, respectively. Digested mtDNA fragments of Acanthamoeba sp. YM-4 contained nine and seven same size fragments, respectively, from a total of 67 and 69 fragments observed in A. culbertsoni and A. polyphaga. An estimate of the genetic divergence was 10.1% between Acanthamoeba sp. YM-4 and A. culbertsoni, and 9.9% between Acanthamoeba sp. YM-4 and A. polyphaga.

Acanthamoeba↗
PubMed1998

[Isolation and identification of Agrobacterium spp. from cherry crown galls and their sensitivities to agrocin 84].

Crown galls were sampled from cherry yards of Shandong, Hebei, and Liaoning provinces. 46 pathogenic strains were isolated. Physiological and biochemical tests revealed that 4 strains were Agrobacterium tumefaciens(bio. 1) and that the other 42 strains were A. rhizogenes (bio. 2), according to the classifications and nomenclatures of the genus Agrobacterium and the species revised by Sawada et al and Bouzar. The Ti plasmids of all strains were nopaline type. All strains were sensitive to agrocin 84, which suggested that crown gall disease of cherry could be controlled by K84 strain.

Adenine Nucleotides↗
PubMedDate not supplied

[Transcranial Doppler exploration of the brain stem vascularization in neurological pathology].

The hemodynamic alterations in the vertebrobasilar system arteries of 1051 patients are discussed. The aspects revealed by transcranial Doppler are classified as obstructions, stenoses and atherosclerotic type lesions. Their prevalence compared with the clinical diagnosis or through other investigation methods is commented upon, an etiological classification of such alterations in hemodynamics in the basilar and vertebral arteries being attempted. Multiple defect theory seems to be, in such cases as well, the clinical expression accounting for the pathogenic phenomena and response to drug tests.

Adolescent↗
PubMed1988

[Amnestic episodes].

Amnesic episodes, by no means infrequent occurrences, are likely to trigger off anxiety in the patient and to evade adequate diagnostic interpretation. They consist of an isolated disturbance of short-term memory, manifesting itself as a permanent memory gap. The clinical features may vary from a conspicuous behaviour with stereotype repetition of questions to a completely inconspicuous picture with flawless execution of even highly differentiated behaviour patterns. The vegetative state may either be completely undisturbed or vary from mild impairment with nausea and vertigo to marked vegetative disorder. We are advocating a classification in 3 groups: a) "Genuine" amnesic states as symptoms of impaired blood flow in the basilar system in the absence of other etiological clues. b) "Symptomatic" amnesic episodes with tangible pathogenic factors, such as injury of the head and cervical spine, epilepsy, intoxication with various agents. The "genuine" amnesic states can also be regarded as transitory ischemic attacks of the basilar system. They show the following criteria: preponderance in females beyond middle age, duration of several hours, relatively high frequency of vascular risk factors and degenerative changes in the cervical spine, often triggered off by stress on the cervical spine, low tendency towards recurrence, general clinical benignity. In consequence, we stress the importance of etiological clarification before the onset of therapy. After the diagnosis of "genuine" amnesic state has been established, treatment has to be in accordance with the principles of basilar stroke therapy with subsequent vascular prophylaxis. Nevertheless, because of possible therapeutic or forensic consequences, the "symptomatic" states have to be kept in mind.

Adult↗
PubMed1982

[Auto-immunity and insulin-dependent diabetes].

Many observations suggest that auto-immune process are activated during the beta-cell destruction in insulin-dependent diabetes (IDD): they include association with organ specific auto-immune disease, frequency of circulating anti-organ antibodies, circulating anti-islet cell antibodies, insulitis-like lesions in the pancreas and in vitro lymphocytic reaction against pancreatic antigens. However, it is still uncertain if these reactions are actually involved in the beta cell destruction. Cytotoxicity experiments on beta cells in culture and animal models support this hypothesis. Nosologic classification which categorizes an autoimmune type of IDD, a viral type of IDD and a large proportion termed idiopathic IDD may be a useful device to further our understanding of the pathogenic pathways but may be open to criticism of undue simplification as in this presumably multifactorial disease, the differences between affected individuals may be quantitative and not qualitative.

Animals↗
PubMed2006

Antiphospholipid antibodies and the antiphospholipid syndrome: an update on treatment and pathogenic mechanisms.

PURPOSE OF REVIEW: The antiphospholipid syndrome is a disorder of recurrent thrombosis, pregnancy loss and thrombocytopenia associated with the presence of antiphospholipid antibodies and persistently positive anticardiolipin or lupus anticoagulant positive tests. Since its recognition in the 1980s, growing interest in the field, not only with respect to diagnosis and treatment, but also regarding the pathogenesis of antiphospholipid antibodies, has emerged. RECENT FINDINGS: First, this review addresses the recently updated classification criteria for diagnosis and treatment of the antiphospholipid syndrome. A discussion on the newly described potential beneficial roles of hydroxychloroquine and the statins for the treatment of antiphospholipid syndrome-associated clinical manifestations is included. Importantly, this article analyzes recent data that examine the molecular and intracellular events that antiphospholipid antibodies trigger in target cells, as well as new findings in the identification of the receptors for these antibodies on the membrane of those cells. A separate section discusses novel pathogenic mechanisms of antiphospholipid antibodies, including the activation of complement and their interaction with homologous catalytic domains of several serine proteases of the coagulation system. SUMMARY: Understanding the molecular interactions and the intracellular signaling that antiphospholipid antibodies trigger, new therapeutic and targeted strategies to ameliorate clinical manifestations in patients with antiphospholipid syndrome may be established.

Antibodies, Antiphospholipid↗
PubMed1992

Molecular evolution of the fungi: human pathogens.

The morphological, ecological, and clinical diversity among ascomycete fungi that are pathogenic to humans suggest that the potential for pathogenicity may have arisen multiple times within these higher fungi. We have obtained 18S ribosomal DNA sequences from a diverse group of human pathogenic fungi in order to determine their evolutionary origins. The fungi studied include a skin pathogen that is confined to humans (Trichophyton rubrum) and three systemic, facultative parasites that cause histoplasmosis (Histoplasma capsulatum), blastomycosis (Blastomyces dermatitidis) and coccidioidomycosis (Coccidioides immitis) in humans and other higher animals. Also included in our analysis are representatives of non-pathogenic fungi, as well as two opportunistic pathogens, Pneumocystis carinii and Candida albicans, that cause severe disease in immunocompromised individuals, especially those with AIDS. Two of the fungi we sequenced, T. rubrum and C. immitis, are limited to asexual modes of reproduction and therefore lack the sexual structures that are most useful for evolutionary comparison as well as being essential for classification among the higher fungi. Coccidioides immitis is particularly problematic owing to its contradictory and confusing asexual morphologies, which have caused it to be placed in three fungal classes and the protista. Our analysis shows that the specialized, superficial parasite and the systemic, facultative parasites, including C. immitis, are closely related ascomycetes, which clearly demonstrates the power of molecular characters to compensate for missing or confusing reproductive morphology. Analysis also shows that the opportunistic pathogens are more distantly related, with the likely explanation that pathogenicity has arisen more than once within the Ascomycetes.

Base Sequence↗
PubMed1991

DNA fingerprinting and electrophoretic karyotype of environmental and clinical isolates of Candida parapsilosis.

The endonuclease restriction pattern (DNA fingerprinting) and the electrophoretic karyotype of 16 Candida parapsilosis isolates from environmental and clinical sources were investigated. DNA from both whole cells and separated mitochondria was digested with enzymes, including EcoRI, BamHI, KpnI, BglII, HpaII, PvuII, and HindIII. Regardless of their source and pathogenic properties, all isolates showed a uniform, reproducible, and overlapping whole-cell DNA fingerprinting with each endonuclease digest. Mitochondrial DNA fragments were, in all cases, major contributors to the total cellular DNA restriction pattern. In contrast, the electrophoretic karyotype generated by rotating field gel electrophoresis (RFGE) or contour clamped homogeneous field electrophoresis (CHEF) showed a remarkable polymorphism among the isolates. This polymorphism concerned the smaller molecular size section of the karyotype (range, 1.8 to 0.7 Mb), where at least two to five chromosomal bands could be consistently detected by both RFGE and CHEF. Larger (greater than or equal to 3.0 to 1.9 Mb) chromosome-sized DNA bands (four in CHEF and three in RFGE) were quite distinct and common to all isolates. Thus, seven karyotype classes could be defined, on the basis of both the number and size of putative chromosomes. The three categories of isolates (soil, vaginal, and hematological) were not randomly distributed among the seven classes. In particular, the four hematological isolates had a karyotype pattern which was clearly distinct from that shown by the three environmental isolates, and of the nine vaginal isolates only one shared a class with isolates from another source (soil). Although tentative, the classification was totally consistent with the independent and reproducible results obtained by the two pulse-field electrophoretic techniques employed. It is suggested that the electrophoretic analysis of the karyotype might be particularly useful for epidemiological and pathogenicity studies on biotypes of C. parapsilosis.

Candida↗
PubMed2006

Implications for molecular mechanisms of glycoprotein hormone receptors using a new sequence-structure-function analysis resource.

Comparison between wild-type and mutated glycoprotein hormone receptors (GPHRs), TSH receptor, FSH receptor, and LH-chorionic gonadotropin receptor is established to identify determinants involved in molecular activation mechanism. The basic aims of the current work are 1) the discrimination of receptor phenotypes according to the differences between activity states they represent, 2) the assignment of classified phenotypes to three-dimensional structural positions to reveal 3) functional-structural hot spots and 4) interrelations between determinants that are responsible for corresponding activity states. Because it is hard to survey the vast amount of pathogenic and site-directed mutations at GPHRs and to improve an almost isolated consideration of individual point mutations, we present a system for systematic and diversified sequence-structure-function analysis (http://www.fmp-berlin.de/ssfa). To combine all mutagenesis data into one set, we converted the functional data into unified scaled values. This at least enables their comparison in a rough classification manner. In this study we describe the compiled data set and a wide spectrum of functions for user-driven searches and classification of receptor functionalities such as cell surface expression, maximum of hormone binding capability, and basal as well as hormone-induced Galphas/Galphaq mediated cAMP/inositol phosphate accumulation. Complementary to known databases, our data set and bioinformatics tools allow functional and biochemical specificities to be linked with spatial features to reveal concealed structure-function relationships by a semiquantitative analysis. A comprehensive discrimination of specificities of pathogenic mutations and in vitro mutant phenotypes and their relation to signaling mechanisms of GPHRs demonstrates the utility of sequence-structure-function analysis. Moreover, new interrelations of determinants important for selective G protein-mediated activation of GPHRs are resumed.

Animals↗
PubMedDate not supplied

Anaerobes in waters.

The classification of anaerobic bacteria in the aquatic environment with regard to their ability to survive in extreme environments (such as high or low temperatures, high salinity and pH) as well as the pathogenicity of Clostridia are presented briefly in this article. The importance of anaerobic bacteria in environmental pollution and several types of corrosion is discussed. The usefulness of anaerobic bacteria as pollution indicators of pollution in the aquatic environment and the methods used for their isolation, enumeration and identification are also presented.

Journal Article↗
PubMedDate not supplied

Vasculitis in systemic lupus erythematosis.

Vasculitis in connective tissue diseases is not an uncommon complication. Vasculitis complicates both rheumatoid arthritis and systemic lupus erythematosis (SLE) in about 4% of cases. Cutaneous lesions, representing small-vessel involvement, are most common; however, widespread, necrotizing visceral medium-and large-vessel involvement, mimicking primary vasculitic syndromes, may also occur. Connective tissue disease-associated vasculitis is separated from primary vasculitis syndromes in classification schemes. Granulomatous large-vessel disease does not occur in connective tissue diseases, suggesting a different pathogenesis. In most disorders, the etiology of vascular inflammation in not completely understood, but basic pathogenic mechanisms can often be distinguished. The role of immune complexes in the inflammatory manifestations of SLE is recognized, and other pathogenic factors such as antineutrophil cytoplasmic antibodies, common in other vasculitides, are infrequent. A diverse spectrum of clinical features, due to inflammatory involvement of arterial and venous vessels of all sizes, characterize several connective tissue diseases including Behçet's disease and SLE. The recognition of disease manifestations due to vasculitis in these disorders has important implications for treatment and may be critical to reduce morbidity and mortality.

Humans↗
PubMed2005

Tropical dermatology: fungal tropical diseases.

UNLABELLED: Fungal infections are common in tropical countries and can have an important impact on public health. Lobomycosis is a common fungal infection in the tropical rain forest of South America, and paracoccidioidomycosis (South American blastomycosis) is a widespread and sometimes severe illness. Penicilliosis marneffei is an opportunistic infection of AIDS patients in southeast Asia. Chromoblastomycosis and mycetomas are causes of morbidity around the world. Sporotrichosis is a worldwide subcutaneous mycosis with a high incidence in tropical countries and is an important illness in immunocompromised patients. Rhinosporidiosis was classed as a fungal infection but is now considered a protistan parasite that belongs to the class Mesomycetozoea. It is included in this review because of its historical classification. In the past, most of these mycoses were restricted to specific geographic areas and natural reservoirs. There are, however, situations in which people from other regions come in contact with the pathogen. A common situation involves an accidental contamination of a traveler or worker who has contact with a tropical mycosis. Even minor trauma to the skin surface or inhalation of the fungal conidia can infect the patient. Thus recognition of the clinical symptoms and the dermatologic findings of the diseases, as well as the geographic distribution of the pathogens, can be critical in diagnosis of the tropical mycoses. This review discusses some of the more common tropical subcutaneous and systemic mycoses, as well as their signs, symptoms, methods of diagnosis, and therapies. LEARNING OBJECTIVE: At the completion of this learning activity, participants should be able to recognize the clinical and histologic presentations of tropical fungal diseases with cutaneous manifestations and be familiar with the appropriate therapies.

Animals↗
PubMed2005

An association between hemifacial microsomia and facial clefting.

PURPOSE: Hemifacial microsomia (HFM) is a relatively uncommon malformation, a far second to cleft lip/palate (CL/P). Transverse oral cleft ("macrostomia") is known to be associated with HFM, but there are also reports of concurrent CL/P. We undertook a retrospective study of patients with HFM to document the prevalence of facial clefting. The hypothesis is that the coexistence of facial clefts and HFM suggests a common pathogenic mechanism. MATERIALS AND METHODS: Records of 198 HFM patients from the database of the Craniofacial Centre at Boston Children's Hospital were reviewed. The age, gender, predominant side of HFM, OMENS classification, and presence, size, and type of cleft (CL/P, transverse oral cleft, or oro-ocular cleft) were documented. We performed chi 2 , t test, and Fishers exact analyses to evaluate the association of facial clefting with HFM. RESULTS: There were 100 males and 98 females in the HFM study group, with a mean age of 15.3 years (range, 1 to 50 years); 90 were right-sided (45%), 79 were left-sided (40%), and 29 were bilateral (15%). Twenty patients had a CL/P (10%), and of these 15 had unilateral CL/P (UCL/P), equally distributed between right and left sides, and 5 had bilateral CL/P (BCL/P). There were 9 males and 11 females with combined HFM and CL/P. Cleft of the oral commissure (macrostomia) was present in 46 (23.0%) of the HFM patients with a left-to-right-to-bilateral ratio of 5:6:1. There was a significant association between the predominant side of HFM and the side of CL/P ( P < .001) and macrostomia ( P </= .001). We also showed a correlation between the severity of the orbital and mandibular deformities in HFM and the coexisting facial cleft. CONCLUSIONS: An association implies concurrence, more often than by chance, of 2 or more anomalies and suggests an etiopathologic link. The finding of ipsilateral labial clefts in 10% of HFM patients, and the differing demographic distribution from common labial clefts, suggests an overlapping pathogenesis. Whether the cause is genetic or environmental, we hypothesize that there may be a common pathway leading to a disturbance in neural crest cell migration in HFM patients who also have a facial cleft.

Adolescent↗
PubMed1966

Presence of the arginine dihydrolase pathway in Mycoplasma.

Barile, Michael F. (Division of Biologics Standards, National Institutes of Health, Bethesda, Md.), Robert T. Schimke, and Donald B. Riggs. Presence of the arginine dihydrolase pathway in Mycoplasma. J. Bacteriol. 91:189-192. 1966.-The presence of the arginine dihydrolase pathway was examined in 61 Mycoplasma strains representing at least 18 Mycoplasma species isolated from nine different sources: human, bovine, avian, murine, swine, goat, canine, sewage, and tissue cell culture origin. Some species were represented by only one or two strains. Different strains of the same species gave the same results. Ten species (56%) were positive. Many nonpathogenic Mycoplasma species (M. hominis, type 1 and 2, M. fermentans, M. salivarium, and M. gallinarum) were positive, whereas most pathogenic species (M. pneumoniae, M. gallisepticum, M. neurolyticum, and M. hyorhinis) were negative. The presence of arginine dihydrolase activity among Mycoplasma species may prove to be useful for purposes of identification and classification.

Journal Article↗