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PubMed1983

Collagen genes and brittle bones.

The heritable diseases of connective tissue are caused by known or putative defects in the synthesis of collagens, proteoglycans, glycoproteins, or attachment proteins of the extracellular matrix. Abnormal synthesis of type I collagen has been reported in several clinical variants of osteogenesis imperfecta. Because clinical classification of these variants is limited by genetic heterogenity and variable expression, biochemical criteria should be used for precise definition of the variants. Newly recognized molecular defects in osteogenesis imperfecta include the diminished formation of type I collagen and alpha-1[I] messenger RNA; abnormal synthesis or faulty assembly of alpha-2[I]; deletion or insertion of base pairs in the gene for alpha-1[I] or alpha-2[I] and failure to secrete type I procollagen; and substitution of cysteine for glycine in the triple helix. These molecular defects are characteristic of several variants. However, the molecular lesion in most cases of severe osteogenesis imperfecta has not been identified; synthesis of type I collagen and alpha-1: alpha-2 chain ratios appears to be normal. Production of an alpha-1 trimer may represent one such lesion in severe disease.

Bone Diseases, Developmental↗
PubMed1990

Thrombotic thrombocytopenic purpura and related disorders.

This article provides us with background information on the disease. Clinical features, variants and classification, laboratory findings, and pathology are discussed. Knowledge of the disease's pathogenesis has increased recently and specific causes discussed are predisposing factors, triggering agents, endothelial damage, defective PGI2 bioavailability, FVIII/vWF multimeric structure abnormalities, platelet activation, and hemolytic anemia. Proposed specific therapies discussed are steroids, heparin, antiplatelet agents, prostacyclin, splenectomy, immunosuppressive agents, plasma infusion, and plasma exchange.

Adolescent↗
PubMed1987

[Electron-microscopic study of neuroendocrine tumors of the lung].

An electron-microscopic study was made of carcinoids, malignant carcinoids and small-cell lung cancer. These neoplasms are shown to represent one histogenetic group--neuroendocrine tumours (apudomas) of the lung. One can distinguish 3 main structural forms among them, i.e. epithelioid, sarcoma-like and symplastic. According to the ultrastructural criteria the neoplasms mentioned can be classified by their differentiation degree, as well, intermediately and poorly differentiated variants. This classification correlates well enough with the catamnesis of patients and may serve for prognosis of the disease.

Apudoma↗
PubMed1981

[The problem of cysto-sarcoma phyllodes (author's transl)].

Problems in the diagnosis and treatment of cysto-sarcoma phyllodes in thirteen women are discussed. This is a rare breast tumour which must be regarded as semi-malignant. Its malignancy consists of its tendency to recurrence and the development of distant metastases. Five patients had one or more recurrences and three patients had metastases which were fatal. Radiological and thermographic diagnosis of small tumours is unreliable. It is not possible to distinguish the benign from the malignant variants. Accurate classification depends on histological examination. The authors consider removal of the glandular tissue or simple mastectomy to be the best form of treatment.

Adolescent↗
PubMedDate not supplied

Frostbite: an overview with case presentations.

Much of the interest in frostbite has arisen from various military experiences including the Korean war, World War II, and Napolean's battles in Russia and Poland. Historically frostbite has been not only a military problem, but also a problem in high-altitude climbers and the more recently investigated homeless population. However, the physician should not disregard frostbite as only victimizing the poor and indigent. Anyone who is exposed to harsh winter conditions over a long period of time can suffer from frostbite. Many milder cases of frostbite presented to Cook County Hospital in Chicago were simply due to prolonged winter exposure when a motorist's care broke down. The authors present a review of the variants, pathophysiology, classifications, predisposing factors, and treatment of frostbite. Five cases of frostbite will also be presented from Cook County Hospital in Chicago, IL.

Adult↗
PubMed1994

Hepatitis C virus genotypes: an investigation of type-specific differences in geographic origin and disease.

Because of the nucleotide sequence diversity of different isolates of hepatitis C virus, it has become important to clarify whether distinct genotypes of hepatitis C virus vary with respect to pathogenicity, infectivity, response to antiviral therapy and geographic clustering. We assessed nucleotide sequence variability in the 5' noncoding region of hepatitis C virus, using restriction enzymes to analyze the distribution of hepatitis C virus genotypes, in 80 patients with chronic hepatitis C virus infection. Genotypes were correlated with demographic, clinical and histological features. Thirty-seven patients were infected with type 1, 10 had type 2 and 8 had type 3, and another 23 were infected with a new distinct hepatitis C virus type now classified as type 4. Two were infected with variants whose classification are uncertain. Types 1, 2 and 3 were found in patients from the United Kingdom, southern Europe, Asia, Africa and South America. Nineteen of 23 type 4 genotype isolates were from Middle Eastern patients, compared with 0 of 37 type 1 isolates (p < 0.001). Of 21 Middle Eastern patients, 19 (90.4%) had type 4 hepatitis C virus (p = 0.001, odds ratio = 9). We found no significant difference between the mean ages or mean serum aminotransferase concentrations between the various types. Types 1, 2, 3 and 4 were found in patients with mild-to-moderate disease or severe disease. However, 21 of 29 (72.4%) patients with type 1 who underwent liver biopsy had severe chronic hepatitis, cirrhosis or hepatocellular carcinoma histologically; 8 had mild or moderate chronic hepatitis without cirrhosis (p = 0.03, odds ratio = 2.6).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1977

An immunological investigation of hemophilia B with a tentative classification of the disease into five variants.

23 patients with hemophilia B have been investigated by means of several immunological methods. 16 patients (69.9%) had no detectable factor XI antigen. Five had a normal factor IX antigen and the electrophoretic mobility of this abnormal factor IX was similar to that of its normal counterpart. One of these five patients had hemophilia Bm, since ox brain thromboplastin clotting time was severely prolonged. The remaining two patients had reduced or decreased factor IX antigen. Several patients showed a slight protongation of ox brain thromboplastin time due to an associated slight factor VII deficiency. On the basis of these results, a tentative classification of hemophilia B into five variants is proposed, namely: hemctor IX antigen; hemophilia Bra, or with reduced factor IX antigen; hemophilia Bm, or with normal factor IX antigen and severely prolonged ox brain thromboplastin; hemophilia B patients is feasible only by means of a battery of tests, namely:factor IX activity assay, factor IX antigen determination, ox brain thromboplastin clotting time, factor VII activity assay.

Factor IX↗
PubMed2026

Phenotypic manifestations and variant reclassification of germline PTEN variants: a nationwide Danish study.

BACKGROUND: Classification of heterozygous germline PTEN variants in patients with, or suspected of having, PTEN hamartoma tumour syndrome (PHTS) remains challenging. Accurate classification is essential as these patients require lifelong cancer surveillance. METHODS: We identified all patients with a PTEN variant previously classified as a variant of uncertain significance (VUS), likely pathogenic (LP) or pathogenic (P), collected clinical data and reclassified all variants using the latest PTEN gene-specific American College of Medical Genetics (ACMG) guidelines. Moreover, genotype-phenotype correlations were assessed. RESULTS: 167 patients from 112 families were enrolled. Eighty-seven unique PTEN variants were identified, including 20 novel variants. After applying the PTEN gene-specific ACMG guidelines, 32 variants (36.8%) were reclassified, resulting in 60 PTEN variants classified as LP/P (69.0%), 18 variants classified as VUS (20.7%), while 9 variants were classified as LB/B (10.3%). Genotype-phenotype correlation was performed among 104 patients with LP/P variants: 51 cancer cases were recorded in 41 patients and a distinct PHTS phenotype was observed in 25% of patients, with macrocephaly being present in 99% of patients with a known head circumference. Twenty-three patients had neurodevelopmental delay and/or autism, and we observed an increased prevalence of missense variants in these patients. CONCLUSION: We identified 87 different PTEN variants, and application of PTEN gene-specific ACMG guidelines led to reclassification of 32 variants (36.8%), underscoring the importance of regular variant reassessment using the most recent gene-specific guidelines, ensuring optimal patient management and surveillance.

Genetic Predisposition to Disease↗
PubMed1991

Rapid detection and initial characterization of genetic variants of human serum albumin.

We have studied the detection and classification of genetic variants of human serum albumin by electrophoresis. Samples from 10 patients who were heterozygous for eight different albumin variants were studied by two methods. In agarose gel electrophoresis, each of these variants has an abnormal mobility and can be classified on the basis that structural changes at the N-terminus abolish 63Ni binding. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole serum, glycosylated variants are easily detected because of their greater apparent molecular mass.

Autoradiography↗
PubMed1980

[Functional classification of ischemic heart disease].

A modified variant of the functional classification of patients with ischemic heart disease standard for all stages of rehabilitation is suggested. It is based on the rate with which the program of treatment is fulfilled and on the determination of the clinico-functional parameters and the physiological reaction of the patient during rehabilitation. The classification was tested on 98 patients with macrofocal myocardial infarction (average age 53.5 years) who underwent a successive rehabilitation program at the inpatient, sanatoria, out-patient stages with a subsequent two-year follow-up as out-patients after they had resumed working. The classification proved sufficiently informative in regard to the prognostication of the restoration of working capacity and the character of the course taken by ischemic heart disease.

Adult↗
PubMed1980

[Certain features of the morphology of Hodgkin's disease].

Investigation of lymphogranulomatosis process in 42 patients included histological examinations of chains of lymph nodes with varying duration of their involvement. Lymphogranulomatosis was shown to begin with focal involvement of lymph nodes. The specific focus is initially located in the paracortical zone, then the pathological process extends into the medullary zone and finally into the cortical zone. As early and finally into the cortical zone. As early as the focal lesions occur the cell composition already corresponds to one of histological variants of lymphogranulomatosis (by Lukes' classification). No transition from variants with lymphoid prevalence to those with lymphoid exhaustion in groups of removed lymph nodes from the same patient was observed indicating independent development of each histological type and its stability for a given patient. No correlation between the clinical stage and morphological type of lymphogranulomatosis was established.

Adolescent↗
PubMed1991

[The characteristics of the clinical course of lymphosarcomas in conformity with the morphological variants of the WHO and Working Formulation classifications].

Histological and cytological preparations of the lymph nodes, spleen, bone marrow and other tumors from 140 patients with different variants of lymphosarcomas were subjected to a comparative clinicomorphological analysis. The data obtained were correlated to the WHO classification and the working formulation of non-Hodgkin's lymphomas intended for clinical use. It has been found desirable that the working formulation may be used for predicting the disease course and elaboration of the programs of lymphosarcoma treatment.

Adolescent↗
PubMed1988

[Genetic variants of human albumin: structural characterization of allotypes used as references for electrophoretic classification].

Eight different types of genetic variants of albumin are observed in the French population. The analysis of electrophoretic patterns of sera containing these variants, performed a three different pHs (8.6, 5.0 and 6.9) after addition of a reference protein (transferrin), allows the identification each variant by a quantitative estimation of its relative mobilities. The accuracy and reproducibility of the technique make it a useful reference method, commonly employed for studying European variants. The samples used as references for five genetic variant types, proalbumins Christchurch and Lille, albumins Vanves, B and Reading, were subjected to sequence analysis to determine the nature and localization of their structural change. Together with the mutations of albumins Gent and Roma previously described, the data presented here make available seven reference specimens for which the structural changes are characterized out of the eight variants known to exist in France.

Amino Acid Sequence↗
PubMed1989

[Clinico-morphologic parallels in malignant lymphoma].

Concurrent clinicomorphological studies were carried out in patients with malignant Hodgkin's and non-Hodgkin lymphomas treated in the Hematologic Clinic of the High Medical Institute in Pleven. The frequency of the different clinicomorphological variants and their classification in accordance with their initial localization, clinical stage and histological variant were studied. Some clinicomorphological features of the patients studied are analyzed.

Adult↗
PubMed1981

[Classification and the criteria of hypertrophy of the heart based on data from the weighing of its separate parts].

Variation statistical analysis of summary data of separate weighing parts of the hearts of 605 apparently normal subjects was carried out. The ranges of normal variations, the borders of the transitional zone, and criteria of pathology by 15 parameters of the myocardium weight were determined by the method of sigmal deviations and centil method. Two variants of pathoanatomical classification of changes in the heart weight are proposed. The first variant is based on two criteria: myocardial-height and ventricle indices. It includes 6 forms of changes of the muscle weight: absolute and relative hypertrophy of the right and left ventricles, combined hypertrophy of both ventricles, and myocardial atrophy. The second variant is based on comparative evaluation of the absolute weight of the right and left ventricles, allowing to distinguish 10 forms of changes of the myocardium weight. Both variants allow an objective and significant classification of any case. Nomograms have been compiled to facilitate the use of the classifications.

Adult↗