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At least 163 records · Page 9Linked to original sources
PubMed2002

High levels of cellular retinol binding protein-1 expression in leiomyosarcoma: possible implications for diagnostic evaluation.

Retinoid bioavailability is regulated by the activity of specific cytoplasmic receptors. High levels of cellular retinol binding protein-1 (CRBP-1) have been documented during experimental arterial and wound-healing processes, but data concerning neoplastic smooth muscle tissues are scarce and/or controversial. This study reports that the expression of CRBP-1 is markedly higher in uterine and gastrointestinal leiomyosarcomas than in leiomyomas and normal myometrium; CRBP-1 was practically absent in normal gastrointestinal smooth muscle tissue. CRBP-1 positivity was particularly elevated in the epithelioid variant of leiomyosarcoma; it was associated with increased proliferative and apoptotic rates and inversely related to smooth muscle differentiation evaluated by alpha- and gamma-smooth muscle actin and desmin expression. Western blotting and reverse-transcription polymerase chain reaction confirmed the observations concerning CRBP-1 and actin isoform expression and revealed higher NF-kappa-Bp65 and RAR alpha and lower Bax protein levels in leiomyosarcoma than in the other conditions. These findings document that a high CRBP-1 expression is associated with smooth muscle malignancy and suggest that CRBP-1 expression represents a new useful marker for the classification of unusual variants of smooth muscle tumors.

Adult↗
PubMed1985

Neuroendocrine neoplasms of the bronchopulmonary tract. A classification of the spectrum of carcinoid to small cell carcinoma and intervening variants.

Eighty-one primary pulmonary neuroendocrine neoplasms were assessed by the classification of Gould and associates. The neuroendocrine features of these tumors were studied by a combination of conventional light microscopy, electron microscopy, and immunohistochemical staining for hormonal substances and neuron-specific enolase. In each case, clinical follow-up was obtained to test the prognostic value of this new pathological classification. This study indicated that bronchial carcinoids are very low-grade neuroendocrine neoplasms that are locally invasive and only occasionally metastasize late in their course. Well-differentiated neuroendocrine carcinomas are relatively low-grade carcinomas that either present with or subsequently develop nodal or distant metastases in 73% of patients. Intermediate cell neuroendocrine carcinomas are highly aggressive tumors often mistakenly called "large cell undifferentiated carcinoma." Their clinical course is comparable to that of small cell neuroendocrine carcinomas, which has a mean survival of 9 months. The different clinical courses of these tumors demonstrate the predictive value of the proposed classification. It appears particularly valuable to identify well-differentiated neuroendocrine carcinoma as a low-grade carcinoma, distinct from true bronchial carcinoids. This classification may resolve some discrepancies regarding the therapy for and prognosis of "carcinoids" and their presumed variants.

Biopsy↗
PubMedDate not supplied

[The association between post anoxic encephalopathy and startle epilepsy].

INTRODUCTION: The startle is a variant of primitive physiological reflex, present in developed animals. It could be defined as a sudden defensive reaction triggered by an adequate sensorial stimulus, most effective if auditory, consisting under a clinical basis on the sudden and sequential contraction of some muscular groups, in first place affecting the facial territory (orbicularis oculi bilaterally), followed by the rest of the cranial nerves, the axial musculature and finally the limbs, predominantly proximal and flexor regions of superior extremities. The pathological startle is that which is precipitated by inadequate stimulus and excessive in response to it (under a low level of intensity or duration). It appears on account of different causes and mechanisms, among them a peculiar form of reflex epilepsy, the startle epilepsy. This form of epilepsy commonly present on infant postanoxic encephalopathy, shares its clinical features with other causes of pathologic startle, even though it presents a very characteristic electroencephalographic semiology. CASE REPORT: We present the case of a child with a startle epilepsy clinically presented as a form of subintrant status epilepticus under the context of a postanoxic encephalopathy secondary to drowsiness. With an adequate treatment it was possible to eliminate the epileptic phenomena, thus notoriously improving his quality of life (vigil and asleep). CONCLUSION: We review the characteristics and classifications of a variant of reflex epilepsy, the startle epilepsy.

Child, Preschool↗
PubMed2001

Pseudoexstrophy in a female child.

A six-year-old female patient presenting with a swelling in the infraumbilical part of the abdomen, bulging out on straining, was diagnosed to have pseudoexstrophy bladder. The urinary tract was normal. The patient had bifid clitoris. There was no other associated malformation. Surgical repair of abdominal wall defect was done successfully. A new classification of exstrophy variants is proposed.

Abdominal Muscles↗
PubMed2002

Genetic diversity in apricot revealed by AFLP markers: species and cultivar comparisons.

The genetic diversity of apricot ( Prunus armeniaca; 2n = 16) was studied using AFLP markers. Forty seven apricot cultivars were selected from the following geographic regions: Europe, North America, North Africa, Turkey, Iran and China. Five EcoRI- MseI AFLP primer combinations revealed 416 legible bands, of which 379 were polymorphic markers. A similarity matrix was prepared using the simple matching coefficient of similarity. A UPGMA dendrogram demonstrated a gradient of decreasing genetic diversity of varieties from the former USSR to Southern Europe. This is coherent with the historical dissemination of apricot from its center of origin in Asia. The American cultivars were intermediate demonstrating a different genetic base than the European and/or Mediterranean cultivars. Euclidean distances from the first ten Factorial Component Analysis coordinate axes were used to generate a tree using the Ward algorithm. The results of these analyses were evaluated based on the known geographic origins and agronomic characteristics of the cultivars studied. Four cultivar groups were identified: Diversification, Geographically Adaptable, Continental Europe and Mediterranean Basin. To evaluate the relationship of the common apricot with some closely related species, one or two accessions of the following related species or sub-species from within the section Armeniaca were included in the analysis: Prunus armeniaca var. ansu, Prunus mume, Prunus brigantiaca, Prunus dasycarpa, and Prunus holosericea. A Neighbour Joining dendrogram was made using the similarity matrix. The P. holosericea accession fell well within the cultivar group, thus supporting its classification as a variant of P. armeniaca. The P. armeniaca var. ansu accession was sister to the common apricot cluster with a bootstrap value of 96%. P. mume was farther removed. P. brigantiaca was the most-distant from the common apricots. P. dasycarpa was intermediate between P. brigantiaca and P. mume, in accord with its plum-apricot hybrid origin. The results have a direct application for the selection of new breeding progenitors.

Journal Article↗
PubMed1998

Clinical and molecular genetics of primary dystonias.

Primary dystonias are movement disorders with dystonia as a major symptom. They are frequently inherited as Mendelian traits. There are at least eight clinically distinct autosomal dominant and two X-linked recessive forms. In addition, pedigree analyses suggest the occurrence of an autosomal recessive variant. The clinical classification is increasingly being replaced by a genetic one. To date gene loci have been identified in at least six autosomal dominant forms, i.e., in idiopathic torsion dystonia (9q34), focal dystonia (18p), adult-onset idiopathic torsion dystonia of mixed type (8p21-q22), dopa-responsive dystonia (14q22.1-q22.2), and paroxysmal dystonic choreoathetosis (2q25-q33; 1p21-p13.3). Gene loci in the X-linked recessive forms have been assigned to Xq13.1 in the X-linked dystonia parkinsonism syndrome and to Xq22 in X-linked sensorineural deafness, dystonia, and mental retardation. The disease genes have been identified in two autosomal dominant forms and in one X-linked recessive form. Mutations in a gene coding for an ATP-binding protein were detected in idiopathic torsion dystonia (DYT1), and the GTP cyclohydrolase 1 gene is mutated in dopa-responsive dystonia (DYT5). In sensorineural deafness, dystonia, and mental retardation, mutations were found in the gene DDP coding for a polypeptide of unknown function. This article reviews the clinical and molecular genetics of primary dystonias, critically discusses present findings, and proposes referring to the known forms, most of which can be distinguished by genetic criteria, as dystonias 1-12.

Carrier Proteins↗
PubMed1976

Pulmonary giant cell carcinoma.

Pulmonary giant cell carcinoma is one of the most highly malignant neoplasms of the lung. Eighteen patients with this tumor are presented. Histologically the neoplasm is composed of a preponderance of multinucleated giant cells, round cells, and spindle cells. Some of the most differentiated tumors show adenocarcinomatous foci and ultrastructural features of secretory epithelium favoring its classification as a variant of pulmonary adenocarcinoma. The giant cells of this neoplasm can be differentiated from those encountered in undifferentiated large cell carcinoma and epidermoid carcinoma by the abundant cytoplasm, the presence of more nuclei and nucleoli, and the significant degree of phagocytosis. The clinical picture and roentgenographic findings present no pathognomonic features.

Adult↗
PubMed1980

Masked giant-cell arteritis.

Five bipsy-proven cases of giant-cell arteritis illustrate some of the lesser known, but not uncommon, masquerades of this disease. The delay in reaching the diagnosis, which is common with these presentations, was a major factor in the emergence of serious sequelae including arotic regurgitation, stroke, and death. To increase awareness of the variety of clinical presentation of giant-cell arteritis, a classification of these variants into cachectic, febrile, and other forms is suggested.

Aged↗
PubMed1998

[Importance of molecular biology in retrovirus and herpesvirus infections].

Molecular biology has long been used as a tool for basic research in virology. Its medical use is recent and has been supported both by numerous technical improvements and the discovery of new human viruses. This is illustrated by the emergence of human immunodeficiency virus (HIV)-1, HIV-2, human T-cell leukemia virus (HTLV)-I/II, and human herpesviruses (HHV) 6, 7 and 8. Polymerase chain reaction (PCR) gave a major boost to an extended use of molecular biology techniques. This resulted in a better knowledge of human viral infections as illustrated by studies on HIV and HHV-8. New viruses have been characterized. Molecular markers have permitted analysis of virus transmission cases, classification of genetic variants and detection of mixed infections. The quantitation of viral load has led to a better understanding of chronic infections and reactivations. As a tool for diagnosis, molecular biology is not yet considered as a universal alternative to classical procedures such as serology and antigen detection. However, major improvements in molecular biology techniques might question current diagnosis strategies in the very near future.

HIV↗
PubMed1992

Nosological considerations of the neurofibromatoses.

We are on the threshold of evaluating the NF1 and NF2 loci with respect to variant forms of the neurofibromatoses. Genetic mapping of NF1, gene cloning and characterization of its encoded product, neurofibromin, provides a framework for the evaluation of the variant forms of NF. This may also apply to NF2 variant forms in the near future. The mapping approach in evaluating variant forms of NF should begin with the rigorous clinical assessment of familial cases whereby the establishment of genetic linkage in families with overlap syndromes might determine if either NF1, NF2, or a separate locus is involved in the phenotype. Conditions mapping to the NF1 locus could then be screened for mutations in hopes of identifying the etiologies of the variant forms of NF. Mutation identification should provide a molecular-based classification scheme for the variant forms of NF, now tentatively divided into alternative and related forms. It is expected that the nosology of the neurofibromatoses will most certainly change as more is learned of the NF1 and NF2 loci.

Diagnosis, Differential↗
PubMed1991

Glucose-6-phosphate dehydrogenase enzyme activity in normal, hemizygote and heterozygote Kelantanese Malays.

This prospective study was performed to quantify glucose-6-phosphate dehydrogenase (G6PD) enzyme activity in deficient males and female heterozygotes. The methods used in the study were the fluorescent spot test, G6PD enzyme electrophoresis on cellulose acetate and quantitative assays. Forty-seven children who had been detected as spot screen deficient at birth were rescreened. Their first degree relatives were also included in the study. The mean enzyme activity of deficient males was 0.74 iu/g Hb (s.d. +/- 0.8), of female heterozygotes was 6.5 iu/g Hb (s.d. +/- 3.2) and of normal males was 12.1 iu/g Hb (s.d. +/- 3.5). The mean activity in deficient males was 6.1% of normal males. Most (35 of 47) of these fell into class 2 in Beutler's classification of G6PD variants. This indicates a population which may be susceptible to favism. Female heterozygotes had an intermediate enzyme activity with a wide scatter. Using a cut off point of enzyme activity of below 9.0 iu/g Hb gave sensitivity and specificity of 87% and 84% in detecting female heterozygotes. This group could be defined more accurately by combining quantitative assays with family studies.

Child, Preschool↗
PubMed1992

The Tridimensional Personality Questionnaire in males at high and low risk for alcoholism.

Cloninger has proposed a tridimensional model as the basis for the classification of personality variants and has developed the Tridimensional Personality Questionnaire (TPQ) as an empirical test of this model. In this study, the TPQ was administered to two groups of young men. One group was comprised of nonalcoholic sons of male alcoholics; the other group consisted of nonalcoholic men with no family history of alcoholism. Since the sons of male alcoholics are considered to be at greater risk to develop alcoholism than the sons of nonalcoholics, it was hypothesized that the two groups would demonstrate differences with regard to one or more personality variants as measured by the TPQ. No statistically significant differences in the three TPQ-subscale scores of the two groups were found.

Adult↗
PubMed1999

PCR-RFLP-detected human papilloma virus infection in a group of senegalese women attending an STD clinic and identification of a new HPV-68 subtype.

Cancer of the cervix is the most common malignant tumor among women in Africa and, in particular, Senegal. Studies of the prevalence of human papilloma virus (HPV) infection in Africa have mainly focused on carcinomas. Data on the presence of the virus in women with normal cervical cytology are scarce. In this study, 158 cytologically normal women who had been referred to the 'Institut Pasteur de Dakar' (Senegal) for various genital complaints were investigated for the presence of HPV on exfoliated cells by PCR-RFLP. HPV was detected in 13.9% of cases. Oncogenic type HPV 16 was the most common type (40.9%), followed by HPV 53 and HPV 58, both detected in 13.6% of cases. Mixed HPV infections were present in 13. 6% of the subjects. Only HPVs belonging to the intermediate-high risk group were detected. These data suggest the need for careful cytological control of patients. A PCR-HPV fragment (GA115) possessing an original RFLP pattern was isolated. After sequencing, it showed a nucleotide homology of 97.1% with HPV 68 and should therefore be considered a new HPV 68 subtype. The use of PCR-RFLP strategy enables detection and typing of all known and as yet unknown genital HPVs. Variant and subtype classification of HPV types identified by oligonucleotide probe methods may need to be refined, especially for less prevalent HPVs and in areas where little information on HPV prevalence is available. More studies are needed to characterize satisfactorily the epidemiology of HPV in Africa.

Adolescent↗
PubMed1999

Immunocytoma: a retrospective analysis from St Bartholomew's Hospital-1972 to 1996.

PURPOSE: To analyze the presentation features and outcome for patients with immunocytoma (IMC) managed at St Bartholomew's Hospital (SBH), London, United Kingdom, between 1972 and 1996. Outcome was compared with that of patients with small lymphocytic lymphoma (SLL)/B-cell chronic lymphocytic leukemia (B-CLL) treated at SBH during the same period. PATIENTS AND METHODS: One hundred twenty-six patients with newly diagnosed IMC were identified. Patients were subclassified (using the Kiel classification) as having lymphoplasmacytoid (n =92), lymphoplasmacytic (n = 24), polymorphous (n = 9), or undetermined (n = 1) IMC. Six patients (5%) had stage I to IIE disease; the rest had advanced disease. Treatment was given according to disease stage. Seven patients were managed expectantly. RESULTS: Eighty-two (69%) of 119 patients responded to treatment, but complete remission was seen in only 15 (13%) of 119. Treatment failed in 29 (24%) of 119 patients. There were three treatment-related deaths; five patients were not assessable for response. When survival of patients with IMC was compared with that of patients with B-CLL/SLL, a significant difference was found (P <. 01); this difference was maintained when only patients in whom the diagnosis was based on lymph node biopsy were considered (P =.01). A comparison of the three IMC subgroups showed that there was a trend (P =.06) toward a difference between B-CLL/SLL and the lymphoplasmacytoid subtype. CONCLUSION: Patients diagnosed with IMC are generally older and present with advanced disease. Conventional therapies usually result in incomplete responses of short duration. Overall, these results support the proposed World Health Organization reclassification of IMC to include lymphoplasmacytoid lymphoma (Kiel classification) as a variant of B-CLL/SLL.

Adult↗
PubMed1989

Genetic and phenotypic heterogeneity in disorders of peroxisome biogenesis--a complementation study involving cell lines from 19 patients.

Disorders of peroxisomal biogenesis include the Zellweger syndrome, neonatal adrenoleukodystrophy, infantile Refsum syndrome, and hyperpipecolic acidemia. These names were assigned before the recognition of the peroxisomal defect and the distinction between phenotypes is uncertain. Recent studies have identified at least four complementation groups, and indicate the presence of at least that number of distinct genotypes. The purpose of the present study was to examine the relationship between genotype and phenotype. We studied cultured skin fibroblasts from 19 patients in whom deficiency of peroxisomes had been established. Complementation analysis was performed with the criterion of complementation being the restoration of the capacity to synthesize plasmalogens when fibroblasts from two patients were fused. Six complementation groups were identified, and consisted of one 13 member group, one two member group, and four groups comprising single cases. The phenotype of each group was examined with respect to age of survival, clinical manifestations, and biochemical alterations. The 13 member group included patients with all of the four currently designated phenotypic entities, while the most common phenotype (Zellweger syndrome) was distributed among five of the six groups. We conclude that the currently used clinical categories do not represent distinct genotypes. Apparently different genes code for a similar phenotype and one defective gene may lead to variant phenotypes. Definitive classification and understanding of these disorders await definition of the specific biochemical defect in each of the genotypes.

Adrenoleukodystrophy↗
PubMed1991

Anal neoplasia and its precursors: facts and controversies.

The normal anal mucosa shows a complex histology, and a large variety of tumors and lesions with more or less malignant potential may arise in this region. Several of these seem to be related to venereal diseases, homosexual behavior, and anal intercourse, and to immunosuppression. Human papilloma virus (HPV) has been identified in many cases, but the relation to the histological picture is not constant and the significance is unclear. However, these observations have helped us to identify risk groups. Histological classification is often difficult and it is likely that the reproducibility is limited. This may, in part, explain different observations with regard to frequency and biological behavior. A reliable diagnosis still largely depends on exact clinical information on location and appearance, detailed knowledge of the normal histology, and careful handling of the specimen. The revised World Health Organization (WHO) classification represents an improvement, but more variants are still identified and a classification based on conventional histology alone seems in many cases unsatisfactory. Immunohistochemistry and hybridization and other techniques hopefully will provide us with improved typing of these lesions.

Adenocarcinoma↗
PubMedDate not supplied

[Treatment in the rupture of suppurating hepatic echinococcosis into the abdominal cavity].

The rational surgical methods of treatment in 85 patients with suppurative hepatic echinococcosis penetrating into the abdomen cavity are presented. The own author's techniques strictly individualized in each case are described in details. The classification of the variants of the complications and their clinical features are given. The advantage of the presented surgical methods has been proved by a reduction in the period of treatment, the number of intraabdominal complications and mortality rate.

Adult↗