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PubMed1994

The neuropathology of progressive supranuclear palsy.

The macroscopical, histological, ultrastructural and immunocytochemical features of progressive supranuclear palsy (PSP) are reviewed. Recent investigations have revealed important differences in the distribution, ultrastructure and immunocytochemical profile of neurofibrillary tangles in PSP and in Alzheimer's disease. Cortical involvement, as demonstrated by the presence of tangles and neuropil threads has extended the neuropathological spectrum of PSP. Quantitative assessments of neuronal populations show neuronal loss, not only in various nuclei of the brainstem, diencephalon and cerebellum, but also in other areas, including the nucleus basalis of Meynert, substantia nigra and neostriatum. A new classification, based on neuropathological criteria, is suggested in order to take into consideration the phenotypic heterogeneity of PSP. This new classification distinguishes three types: typical, atypical and combined cases. Typical (Type 1) cases conform to the original definition of PSP. Type 2, atypical cases are variants of the histological changes characteristic of PSP: either the severity or the distribution of abnormalities, or both of these deviate from the typical pattern. Cases with combined pathology belong to type 3 group: in these the typical pathology of PSP is accompanied by lesions characteristic of another neurodegenerative or vascular disease.

Humans↗
PubMed1997

Prognostic value of objective semen parameters in an in vitro fertilization program.

PURPOSE: The basic semen parameters seem to have a limited predictive value in male fertility. Could other objective sperm analyses be helpful in the choice of the most adapted assisted procreation technique? METHODS: This study concerns 78 infertile couples with insemination failures. For each semen, 21 objective parameters are analyzed in fresh semen and after sperm selection procedure. The 78 couples are then included in an IVF protocol and classified into two groups: fertile (at least one cleaved embryo is obtained) and infertile. RESULTS: Using multiple variant discriminant factorial analysis, we have found nine nonconventional parameters which induce us to define two classes of semen. These two classes fit with the classification into fertile and infertile groups in 74.4% of the cases. CONCLUSIONS: So these parameters allow us to predict the chance of obtaining embryos during an IVF trial and to choose for each couple the most appropriate technique: IVF or ICSI.

Acrosin↗
PubMed2001

Defiant dysphagia: small-caliber esophagus and refractory benign esophageal strictures.

Among causes of defiant dysphagia, two pose a special challenge for the clinician: the small-caliber esophagus and refractory benign esophageal strictures. The small-caliber esophagus is a major cause of dysphagia for solids in young patients with eosinophilic esophagitis. A smooth, diffusely narrow esophageal lumen can be appreciated by barium esophagography or esophagoscopy. The term "small-caliber esophagus" is preferred over "stricture" because of the absence of cicatrization. A "subtle" small-caliber esophagus may defy detection by barium esophagogram and esophagogastroduodenoscopy. The only evidence to its diagnosis is the endoscopic finding of unusually long rents in the body of the esophagus immediately after esophageal dilation. The ringed esophagus seems to be a variant of the small-caliber esophagus, with the additional endoscopic finding of a variable number of rings (few to numerous) throughout the narrowed esophagus. Classification, diagnosis, and management of small-caliber esophagus are discussed in this review. Refractory esophageal strictures have various causes, including gastroesophageal reflux disease, nasogastric tube placement, mediastinal irradiation, and corrosive ingestion. Treatments used to eliminate or reduce the need for frequent esophageal bougienage include acid-suppressive medical therapy, surgery, intralesional corticosteroid injection, and esophageal self-expandable metal stents.

Deglutition Disorders↗
PubMed1991

Acute myelomonocytic leukemia with bone marrow eosinophilia and inv(16)(p13q22),t(1;16)(q32;q22).

A two-year-old girl presenting with de novo acute myelomonocytic leukemia with eosinophilia (French-American-British [FAB] classification, M4Eo) and inv(16)(p13q22), t(1;16)(q32;q22) involving the same chromosome 16 is described. This is the second report of a variant translocation of an inverted chromosome 16 with chromosome 1 at 1q32. However, the segment 1q32----1qter has been exchanged for 16q22----qter and not 16p13----pter, as reported in the previous case. The additional break at 1q32 and the juxtaposition of 1q32----qter onto chromosome 16 could be relevant to the pathogenesis of the disease.

Bone Marrow↗
PubMed2006

Hematopoietic growth factors, signaling and the chronic myeloproliferative disorders.

The chronic myeloproliferative diseases (CMDs) are a group of conditions characterized by unregulated blood cell production, that due either to excessive numbers of erythrocytes, leukocytes or platelets, or their defective function cause symptoms and signs of fatigue, headache, ruddy cyanosis, hemorrhage, abdominal distension, and the complications of vascular thrombosis. In the late 19th century Vaquez provided the first description of polycythemia vera (PV) and Hueck defined idiopathic myelofibrosis (IMF). In 1920, di Guglielmo established criteria for patients with essential thrombocythemia (ET). In 1951, Dameshek argued that these disorders, along with chronic myelogenous leukemia (CML) display many similar clinical and laboratory features [Dameshek W. Some speculations on the myeloproliferative syndromes. Blood 1951;6:372-5], and grouped them. In 2002, the World Health Organization expanded the definition of CMDs to also include chronic neutrophilic leukemia (CNL), chronic eosinophilic leukemia/hypereosinophilic syndrome (CEL/HES) and systemic mast cell disorder (SMCD) [Vardiman JW, Harris NL, Brunning RD. The World Health Organization (WHO) classification of the myeloid neoplasms. Blood 2002;100:2292-302]. While the molecular pathogenesis of CML is well known [Melo JV, Deininger MW. Biology of chronic myelogenous leukemia-signaling pathways of initiation and transformation. Hematol Oncol Clin North Am 2004;18:545-68], and the causes of CEL/HES and SMCD have been identified in about half of all cases [Gotlib J, Cools J, Malone III JM, Schrier SL, Gilliland DG, Coutre SE. The FIP1L1-PDGFRalpha fusion tyrosine kinase in hypereosinophilic syndrome and chronic eosinophilic leukemia: implications for diagnosis, classification, and management. Blood 2004; 103:2879-91; Valent P, Akin C, Sperr WR, Horny HP, Metcalfe DD. Mast cell proliferative disorders: current view on variants recognized by the World Health Organization. Hematol Oncol Clin North Am 2003; 17:1227-41], until very recently the etiologies of the three classically defined CMDs, PV, IMF and ET, were poorly understood. Each of these disorders is characterized by excessive hematopoiesis, a process usually dependent on one or more hematopoietic growth factors (HGFs). This review will focus on how our knowledge of the molecular mechanisms by which HGFs are produced, bind cell surface receptors and transduce survival and proliferative signals have provided the platform on which the multiple origins of CMDs can be understood and novel therapeutic interventions designed.

Chronic Disease↗
PubMed2004

Lower-half facial migraine: a report of 11 cases.

PURPOSE: Vascular pain of the face constitutes a variant of pain of the head, and includes migraine, cluster headache, paroxysmal hemicrania, and a facial variant of the so-called lower-half migraine. Lower-half facial migraine is a condition difficult to classify; according to the international classifications it could not be found as an individual entity. The objective of the present study is to determine the difficulties we encountered in diagnosis, the ineffective treatments provided, and the pharmacologic treatment effect. PATIENTS AND METHODS: A study is made of 11 cases of lower-half facial migraine, corresponding to 10 women and 1 man (mean age, 35 years), commenting on the clinical characteristics of the disorder and its treatment options. The location of the pain often mimics dental pain, and can lead to a mistaken diagnosis and to the application of inappropriate therapeutic measures. Forty-five percent of the patients had a history of endodontic treatment before the development of pain in the initially affected quadrant. Once the pain had developed, extractions were carried out in 36% of cases in an unsuccessful attempt to secure symptom relief. Our pharmacologic treatment consisted of ergotamine in 9 cases and the remaining 2 patients received indomethacin. RESULTS: Nine patients (82%) improved as a result of treatment, with an important reduction in the frequency of the pain episodes and intensity of pain. One patient failed to respond to ergotamine, while another patient failed to improve with indomethacin. Both were prescribed only minor analgesics. CONCLUSION: The treatment of migraine occurring in the face is no different than that provided for pain occurring in the head.

Adult↗
PubMed2003

The dimensional view of personality disorders: a review of the taxometric evidence.

The dimensional view of personality disorders (PDs) represents these conditions as extreme variants of normal personality continua. This widely held view underpins efforts to characterize PDs in terms of established systems of personality description and to overhaul classification of PDs along dimensional lines. A review of 21 taxometric studies of PDs and related variables calls an unqualified version of this view into question. Analyses of the three PDs investigated to date strongly support taxonic (i.e., categorical or discontinuous) models. Implications for the conceptualization and classification of PDs are drawn.

Humans↗
PubMed1982

Enumeration of antigenic sites of influenza virus hemagglutinin.

The antigenic sites on the hemagglutinin of X-31 (H3) influenza virus have been defined by using a competitive radioimmunoassay with a panel of monoclonal antibodies which includes those known to select variants with substitutions of particular amino acids. The capacity of each monoclonal antibody to block the binding of other radioiodinated monoclones to purified hemagglutinin permitted classification of the panel into four separate groups, each of which defined a particular antigenic site on the hemagglutinin molecule. Three of these are located on the polypeptide backbone and correspond to the "hinge," the "loop," and the "tip/interface" of the X-ray crystallographic model of Wiley et al. (Nature [London] 289:373-378, 1981). Nonreciprocal blocking of certain anti-interface antibodies by anti-loop antibody suggests that much of the exposed surface of the head of the hemagglutinin molecule extending from the loop to the interface may be a continuum of epitopes. A fourth antigenic site is carbohydrate in nature, presumably situated on the antigenic oligosaccharide side chains. These four domains are in addition to two antigenic sites defined by monoclonal antibodies that inhibit neither hemagglutination nor infectivity (Breschkin et al., Virology 113:130-140, 1981;' Yewdell et al., Nature [London] 279:246-248, 1979).

Antibodies, Monoclonal↗
PubMed1995

Diagnostic accuracy and linkage analysis: how useful are schizophrenia spectrum phenotypes?

OBJECTIVE: Numerous studies suggest that the nonschizophrenic relatives of schizophrenic patients exhibit psychiatric and other features that discriminate them from normal comparison subjects. These features have been put forth as "spectrum" phenotypes that may be variant manifestations of the schizophrenia genotype. However, most of these studies do not address a key measurement question: does the diagnostic accuracy of these spectrum classifications warrant their use in genetic linkage studies of schizophrenia? METHOD: The authors reviewed 30 studies of putative indicators of the schizophrenic genotype: schizotypal personality disorder, eye tracking dysfunction, attentional impairment, auditory evoked potentials, neurological signs, neuropsychological impairment, and allusive thinking. RESULTS: Although each of 42 measures of these indicators discriminated the relatives of schizophrenic patients from the normal comparison subjects, a diagnostic accuracy analysis suggested that only six of these would improve the informativeness of genetic linkage data. CONCLUSIONS: Many proposed spectrum phenotypes for schizophrenia may not be useful for linkage analysis because of high false positive rates (poor specificity). Future work aimed at describing and developing phenotypes for linkage analysis should assess the diagnostic accuracy of proposed measures.

Attention↗
PubMed1993

The absence of correlations between a clinical classification and ultrastructural findings in amelogenesis imperfecta.

This study was performed to examine whether a clinical classification of different phenotypes of amelogenesis imperfecta could be discernible at the ultrastructural level. Seventeen primary teeth from 16 children with hypomineralization, hypomaturation, or hypoplastic variants of the disease were collected for histologic studies of the enamel by means of polarized light microscopy, scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). Polarization microscopy showed that the enamel was hypomineralized; in six teeth a wavy configuration of the enamel prisms also appeared. Three histomorphologic main types could be discerned. In 10 of the teeth extensive hypomineralization of the bulk of the enamel was found. One tooth had an unusually thick enamel with only a thin normally mineralized surface layer. SIMS images showed less pronounced signals from Ca2+ and Na+ but with stronger signals from Cl- and CN-, representing the organic component of enamel. The SEM images showed an irregular prism pattern with marked interprismatic areas. Irrespective of the clinical appearance or the hereditary pattern the main findings were hypomineralized enamel with or without wavy bands. Neither of the analytical methods used in this paper distinguishes between the clinical phenotypes of amelogenesis imperfecta.

Amelogenesis Imperfecta↗
PubMed2026

Investigating mechanisms of divergent feed efficiency in dairy cows.

Objectives were to investigate the associations between residual DMI (RFI), calculated as the difference between observed minus predicted DMI, with rumen microbiome, digestion, behavior, and metabolism that might explain the differences in RFI in lactating cows. One hundred 50 genotyped Holstein cows in 3 cohorts were used in this cohort study in which exposure was RFI. Rumen microbiota from 114 cows were sequenced, and a subset of 30 cows was used for hepatic mitochondrial respiration analysis. Cows were ranked by RFI and grouped into quartiles (Q1, most efficient, to Q4, least efficient) according to phenotypic (pQ) or genomic (gQ) quartiles of RFI for data presentation. Statistical models fitted the linear and quadratic RFI as continuous explanatory variables. Increasing efficiency, i.e., from larger to smaller RFI values, whether phenotypic or genomic, were associated with reduced DMI, a 3.0 kg/d difference between Q4 and Q1 according to phenotypic RFI (pRFI) and 1.9 kg/d according to genomic RFI (gRFI) without compromising ECM or body tissue reserves. These differences between Q4 and Q1 of pRFI and gRFI resulted in increased feed conversion ratio by an additional 200 and 100 g of ECM/kg DMI, respectively. Both pRFI and gRFI were associated with FA profiles in milk fat, with decreasing proportions of de novo and mixed FA and increasing proportions of pre-formed FA, particularly monounsaturated FA, as efficiency improved. Additionally, pRFI and gRFI were moderately correlated (r = 0.48) and ranking of cows was consistent across the 2 grouping methods (ρ = 0.44). Reducing RFI was associated with less total rumination time, but greater rumination time per kg of DMI by 2.0 and 1.7 min/kg between the extreme quartiles of pRFI and gRFI, respectively. Phenotypically and genomically more efficient cows were associated with less microbial α diversity based on inverse Simpson index. A total of 57 amplicon sequence variant groups were differentially abundant between Q1 and Q4 classified based on pRFI and gRFI, with Prevotella and Succinivibrionaceae shared between phenotypic and genomic RFI classifications. Increasing phenotypic and genomic efficiency was associated with an increased concentration of ruminal NH3-N. Genomically more efficient cows tended to have reduced ruminal pH (gQ1 to gQ4; 6.42 vs. 6.47 vs. 6.43 vs. 6.53) despite eating less. Decreasing pRFI was associated with reduced microbial N yield whereas, it tended to increase microbial N yield relative to the amount of N intake. Collectively, phenotypic and genomic RFI have a moderate degree of agreement matching the estimated heritability of the trait, and mechanisms underlying improved feed efficiency were linked with differences in ruminal microbiota and fermentation, and with increased rumination per kg of DM rather than total-tract digestibility or hepatic mitochondrial respiration.

dairy cow↗
PubMed1999

[Richter's syndrome: analysis of literature data and original observations].

AIM: Review of literature data and original experience with Richter's syndrome. MATERIALS AND METHODS: 250 patients suffering from malignant lymphoproliferative diseases with blood and bone marrow lymphocytosis were observed. 8 (3.2%) of them developed diffuse large-cell lymphoma (criteria and classification of REAL). RESULTS: 5 of the above 8 patients demonstrated spontaneous regression of lymphocytosis. These cases may illustrate transformation (clonal progression) of one morphological variant of malignant non-Hodgkin's lymphoma into another one, more aggressive. For this rare variant of Richter's syndrome running with regression of lymphocytosis the term Richter-Lortolary syndrome is proposed. Lortolary was the first who revealed a decrease of lymphocytosis in Richter's syndrome. The studies of the genome structure, first of all, of immunoglobulin genes show that in Richter-Lortolary syndrome it is easier, to confirm monoclonality of the two tumors (lymphocytic and large-cell) than to reject it. However, the idea of transformation has not been confirmed morphologically yet. CONCLUSION: Development of diffuse large-cell lymphoma in the course of chronic lymphatic tumor does not always indicate terminal state, later stage of tumor progression and poor prognosis.

Female↗
PubMedDate not supplied

Surgical treatment of aortic aneurysms: timing and types of operation.

The work reports the experience with 88 cases of aortic aneurysms, 61 of them having been treated surgically. The conventional classification of aortic aneurysms which permits one to define the disease precisely and to time the operation should be selected for every patient individually. The variant of the main intervention on the aneurysm is finally determined by the surgeon during the operation. The new method of "bandaging" the aneurysm is presented. It is the operation of choice for small aneurysms with preserved elasticity of the wall. The aneurysm is bandaged up to the normal diameter of the aorta by a synthetic bandage. The presence of thrombus is not a contraindication. The immediate and distant results (up to 16 years) of this operation are beneficial.

Adult↗
PubMed1993

Gestational and non-gestational trophoblastic neoplasms: new developments in DNA analysis, metabolic function, diagnosis and treatment.

Recent technological advances have made it possible to further define important molecular biological characteristics of gestational and non-gestational trophoblast neoplasm, as they relate to genetic origin and metabolic, endocrine, and diagnostic functions. Exciting new work with DNA analysis has defined origins of placental site trophoblastic tumors, a variant of choriocarcinoma not previously well understood. Coexistent hydatidiform mole and normal gestation have been diagnostically defined and carried out to viability. Finally, refinement of classification systems and expanded tumor markers offer promise of improved salvage in gestational neoplasms and an enlarging number of non-gestational neoplasms.

DNA, Neoplasm↗
PubMed1997

The gene for the ataxia-telangiectasia variant, Nijmegen breakage syndrome, maps to a 1-cM interval on chromosome 8q21.

Nijmegen breakage syndrome (NBS; Seemanová II syndrome) and Berlin breakage syndrome (BBS), also known as ataxia-telangiectasia variants, are two clinically indistinguishable autosomal recessive familial cancer syndromes that share with ataxia-telangiectasia similar cellular, immunological, and chromosomal but not clinical findings. Classification in NBS and BBS was based on complementation of their hypersensitivity to ionizing radiation in cell-fusion experiments. Recent investigations have questioned the former classification into two different disease entities, suggesting that NBS/BBS is caused by mutations in a single radiosensitivity gene. We now have performed a whole-genome screen in 14 NBS/BBS families and have localized the gene for NBS/BBS to a 1-cM interval on chromosome 8q21, between markers D8S271 and D8S270, with a peak LOD score of 6.86 at D8S1811. This marker also shows strong allelic association to both Slavic NBS and German BBS patients, suggesting the existence of one major mutation of Slavic origin. Since the same allele is seen in both former complementation groups, genetic homogeneity of NBS/BBS can be considered as proved.

Alleles↗
PubMed1987

Characterization of epitopes on a variant surface glycoprotein from Trypanosoma congolense by six monoclonal antibodies.

Monoclonal antibodies were isolated from mice immunized with variant surface glycoprotein of Trypanosoma congolense. Five out of the six monoclonals were able to detect epitopes at the cell surface in an indirect immunofluorescence analysis. One antibody did not react. Using protein-A-containing bacterial adsorbent all monoclonal antibodies precipitate glycosylated as well as non-glycosylated variant surface glycoprotein. Carbohydrate chains therefore do not appear to be part of the immunodeterminant structure recognized by the various monoclonal antibodies. Interaction of the monoclonal antibodies with protein fragments obtained by partial proteolysis with V8 protease from Staphylococcus aureus or papain allows the classification of the antibodies into three groups with different epitope specificity.

Animals↗
PubMed1989

Imprint cytology of non-Hodgkin's lymphomas based on a study of 212 immunologically characterized cases: correlation of touch imprints with tissue sections.

The classification of non-Hodgkin's lymphomas (NHLs) has been traditionally based on analysis of histologic sections and has been supplemented more recently by immunologic marker studies. It was the purpose of the present study to illustrate, side-by-side, sections and Romanowsky-stained imprints from the same surgical specimen from practically all categories of immunophenotyped NHLs, including rare and atypical variants that were difficult to classify from the histologic sections alone. Our results indicate that imprint cytology may reveal nuclear and cytoplasmic details not discernible in even the best tissue sections and that it may be selectively helpful in contributing to the classification of NHLs. Our results also show that the relative value of imprint cytology in the classification of malignant lymphomas varies greatly among categories. Specifically, we have found that imprints assist in three ways: the recognition of plasmacytoid features in small cell lymphocytic lymphomas, the recognition of plasmacytoid immunoblastic lymphoma, and the differentiation between NHLs which may be difficult to distinguish histologically. These include (1) small lymphocytic lymphoma versus lymphocytic lymphoma of intermediate differentiation, (2) true histiocytic malignancies versus large cell malignant lymphomas with abundant cytoplasm and/or phagocytosis, (3) anaplastic myeloma versus plasmacytoid immunoblastic lymphoma, (4) large noncleaved versus plasmacytoid immunoblastic lymphoma, (5) lymphoblastic lymphoma versus diffuse small cleaved cell lymphoma, and (6) lymphoblastic lymphoma versus small noncleaved cell lymphoma. Lymph node imprints are easy to prepare and readily interpretable by those experienced in the study of abnormal blood and bone marrow films. Their value as an ancillary methodology aimed at optimal accuracy in the classification of NHLs should be recognized.

Humans↗
PubMed1986

t(4;21) (p16;q22) in blastic crisis of a chronic myeloid leukemia with variant Philadelphia translocation.

A chronic myeloid leukemia (CML) patient who had presented a t(2;9;22) translocation during the chronic phase developed an unusual t(4;21) (p16;q22) translocation during the M2 type FAB classification blastic crisis. The role of these two recombinant chromosomes in the genesis of the terminal phase is discussed, particularly as the breakpoint on chromosome 21 near to the ets-2 oncogene locus, seems to be the same as that described in the t(8;21) (q22;q22) translocation specific of type M2 AML.

Aged↗