Computer-assisted diagnosis: the classification of mammographic breast parenchymal patterns

We have developed a method for the quantification of breast texture by using different algorithms to classify mammograms into the four patterns described by Wolfe (N1, P1, P2 and Dy). The computerized scheme employs craniocaudal views of conventional screen-film mammograms, which are digitized by a laser scanner. We used discriminant analysis to select among different feature-extraction techniques, including Fourier transform, local-contrast analysis, and grey-level distribution and quantification. The method has been evaluated on 117 clinical mammograms previously classified by five radiologists as to mammographic breast parenchymal patterns (MBPPS). The results show differences in agreement among radiologists and computer classification, depending on the Wolfe pattern: excellent for Dy (kappa = 0.77), good for P2 (kappa = 0.52) and N1 (kappa = 0.52) and poor for P1 (kappa = 0.22). Our quantitative texture measure as calculated from digital mammograms may be valuable to radiologists in their assessment of MBPP and therefore useful in establishing an index of risk for developing breast carcinoma.

Detection of TP53 gene mutations in human sarcomas

To determine the frequency and type of TP53 mutations in human sarcomas, we examined exons 5-8 of the TP53 gene in 48 sarcomas using single-strand conformation polymorphism (SSCP) analysis and direct sequencing. Nine tumours had mobility-shifts on SSCP analysis, and sequencing of six of these tumours revealed 10 mutations: one insertion, two deletions and seven point mutations (four transitions and three transversions). Four of these mutations resulted in frame-shifts, one in a truncated protein, four cases in mono-allelic point mutations and one case in an altered splice site. These data show that approximately 20% of sarcomas harbour TP53 gene alterations and illustrate a variety of TP53 gene mutation types.

No association between c-myc amplification and TP53 mutation in sarcoma tumorigenesis

Oncogenes and tumor suppressor genes coparticipate in sarcoma tumorigenesis. We tested 43 sarcomas for c-myc amplification by Southern blot and molecular hybridization techniques and TP53 mutations by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique and direct sequencing of the PCR products. We found eight tumors with c-myc amplification and five different tumors with TP53 mutations but no tumors harbor both c-myc and TP53 alterations. We suggest that c-myc amplification and TP53 mutations do not seem to coparticipate in the tumorigenesis of sarcomas.

[3 nonidiopathic forms of bronchiolitis obliterans organizing pneumonia]

Bronchiolitis obliterans organizing pneumonia is the most serious disease of the bronchioli. An idiopathic form of the disease important for differential diagnosis in incipient forms of pulmonary fibrosis has been reported in the literature, along with other forms associated to drug use, infections, and collagen and localized diseases. We describe 3 patients with bronchiolitis obliterans organizing pneumonia, one associated with rheumatoid arthritis and consumption of gold salts, one with HIV infection and one localized form associated with pulmonary hydatidosis.

Sporadic amplification of the c-fms proto-oncogene in human musculoskeletal sarcomas

Fresh samples of bone and soft tissue sarcoma from 31 patients were analyzed by the Southern technique for amplification or other structural abnormalities of the c-fms oncogene. As a sole finding, amplification of the c-fms (4- and 10-fold) was detected in 2 of 3 cases with a histologic diagnosis of liposarcoma. RFLP analysis disclosed no gene rearrangements associated with the c-fms amplification. The case with the highest amplification of the c-fms gene was disease-free at review. The 2 fms-amplified liposarcomas were aneuploid according to DNA flow cytometry. This is the first study demonstrating amplification of the c-fms proto-oncogene in human liposarcoma. The fact that this structural abnormality of the c-fms gene was only detected in liposarcomas might point to an uncommon but tissue-specific phenomenon.

[Prevention of tuberculosis infection]

Tuberculosis (TB) is a disease caused by a mycobacterium, whose incidence has increased in the past years. This increase is related to the adquired immunodeficiency syndrome (AIDS). Due to its high prevalence, Spain is considered a developing country. The tuberculous infection depends on the degree of functionality of the alveolar macrophages that stimulate the lymphocytes and isolate the bacillus. The infection by mycobacterias can be quantified by means of the cutaneous reaction against tuberculin and mantoux, allowing us to select the subjects that must receive prophylaxis. For its correct interpretation, it is currently recommended to avoid BCG vaccination of children, except in countries with high prevalence of TB.

Amplification of the c-myc proto-oncogene in human chondrosarcoma

The genomic organization of four oncogenes, i.e., c-myc, c-myb, c-Ha-ras, and c-fms, was investigated in fresh surgical specimens from 10 patients with cartilaginous tumors. Among nine chondrosarcomas, six were primary lesions and three local recurrences. The remaining case was a chondroblastoma. Amplification of the c-myc proto-oncogene was the sole abnormality detected in this series, occurring in two chondrosarcomas (four- and eight-fold). No other genetic alteration such as oncogene rearrangement was found. Nor was there any amplification of the other oncogenes studied. Both c-myc-amplified tumors were primary lesions and histologically classified as grade II; according to flow DNA cytometry, one was diploid and the other aneuploid. In our limited series, there was no overall relationship between c-myc amplification, on the one hand, and histologic subtype, malignancy grade, surgical stage, or ploidy level, on the other. Our study shows that amplification of the c-myc oncogene, presumed to be involved in the development of malignancy, is encountered in occasional human chondrosarcomas, however, without any relationship to other well-known features of this tumor entity. The clinical significance of this gene amplification remains to be established.

[Effects of the addition of conditioned media on the response of Fanconi anemia lymphocytes to mitomycin C]

It has been shown that the addition of normal plasma to Fanconi anemia (FA) lymphocyte cultures significantly decreases the frequency of mitomycin C (MMC) induced chromosome aberrations, suggesting that normal plasma contains a diffusible correction factor (CF) which is able to partially complement FA lymphocytes. On the other hand, there is evidence suggesting that FA cells are defective in the DNA postreplicative repair. CF could then be involved in DNA repair processes and in possible inducible mechanisms. In the present study MMC-treated FA lymphocytes were grown during the last 24 hours of culture, in conditioned media obtained from untreated and MMC-treated normal cells. The purpose was to investigate if MMC-stressed normal cells were induced to produce CF in vitro. The results failed to show a constant decrease of FA cells chromosome aberrations when plasma-free conditioned media from MMC-stressed normal cells were added (experiments 2 and 3). However, when the conditioned media were supplemented with normal plasma (experiments 1 and 4) a partial repair of MMC-induced damage of the FA cells was observed. The results suggest the presence of CF in normal plasma and two possible mechanisms of action are suggested: CF is involved in DNA repair of MMC-damaged FA cells or it induces cellular division selecting the less damaged cell population through mitosis.

Members of the alpha-amylase inhibitors family from wheat endosperm are major allergens associated with baker's asthma

We have identified the major antigens or IgE binding components from wheat flour. Thirty-five sera from patients with baker's asthma were used to analyze the reaction with wheat salt-soluble proteins. We found a 15 kDa SDS-PAGE band which reacted with all sera tested. Purified members of the alpha-amylase inhibitor family, which are the main components of the 15 kDa band, were recognized by specific IgE when tested with a pool of reactive sera. Immunodetection after two-dimensional electrophoretic fractionation of crude inhibitor preparations from wheat endosperms also detected several inhibitor subunits as major low-molecular-weight allergens.

The gene for trypsin inhibitor CMe is regulated in trans by the lys 3a locus in the endosperm of barley (Hordeum vulgare L.)

A cDNA encoding trypsin inhibitor CMe from barley endosperm has been cloned and characterized. The longest open reading frame of the cloned cDNA codes for a typical signal peptide of 24 residues followed by a sequence which is identical to the known amino acid sequence of the inhibitor, except for an Ile/Leu substitution at position 59. Southern blot analysis of wheat-barley addition lines has shown that chromosome 3H of barley carries the gene for CMe. This protein is present at less than 2%-3% of the wild-type amount in the mature endosperm of the mutant Risø 1508 with respect to Bomi barley, from which it has been derived, and the corresponding steady state levels of the CMe mRNA are about 1%. One or two copies of the CMe gene (synonym Itc1) per haploid genome have been estimated both in the wild type and in the mutant, and DNA restriction patterns are identical in both stocks, so neither a change in copy number nor a major rearrangement of the structural gene account for the markedly decreased expression. The mutation at the lys 3a locus in Risø 1508 has been previously mapped in chromosome 7 (synonym 5H). A single dose of the wild-type allele at this locus (Lys 3a) restores the expression of gene CMe (allele CMe-1) in chromosome 3H to normal levels.

A barley flour inhibitor of insect alpha-amylase is a major allergen associated with baker's asthma disease

A barley salt-soluble protein of 14.5 kDa, which inhibits the alpha-amylase from the insect Tenebrio molitor, has been identified as a major IgE-binding component of sera from baker's asthma patients. The N-terminal amino acid sequence of this protein indicates that it is a member of a previously described family of alpha-amylase/trypsin inhibitors.

Two-dimensional electrophoresis as a tool for structural and genetic studies of seed proteins from Poaceae and Fagaceae

The application of two-dimensional electrophoretic procedures to structural and genetic studies of seed proteins from Poaceae (including the cultivated cereals) and Fagaceae is described. The following related problems have been considered: covalent and non-covalent association of protein subunits in multiple oligomeric structures; chromosomal locations of genes encoding seed proteins; quantitation of gene products in relation to gene expression and regulation; purification of protein components to study their homology relationships and in vitro activities; evolutionary and phylogenetic relationships; identification of genetic stocks. Isoelectric focusing, pore-gradient electrophoresis, electrophoresis at different pH's, are among the separation procedures used in the first dimension, whereas sodium dodecyl sulfate-polyacrylamide gel electrophoresis and starch-gel electrophoresis at acid pH have been the preferred second-dimensional methods. Dissociating conditions (sodium dodecyl sulfate, Nonidet P-40, or urea) and reducing conditions (2-mercaptoethanol) have been used when required.

Protective effect of triflusal and acetylsalicylic acid against arachidonic acid induced cerebrovascular occlusion in anesthetized rats

Within 60 sec after intracarotid injection of 0.33 mg/kg arachidonic acid, a pronounced attenuation of electrocortical activity, approaching electrocerebral silence, was induced in the ipsilateral hemisphere of anesthetized and heparinized rats. This effect was a consequence of the cerebrovascular occlusion due to platelet aggregates induced by arachidonic acid. This model has been used to evaluate the protective effect of acetylsalicylic acid (ASA) and of triflusal 2 hr after a single oral dose of 50 mg/kg or after 50 mg/kg, for 5 days. Pentylenetetrazol at 10 mg/kg, i.v. exerts a stimulant effect on CNS, and was used as a positive control. ASA and triflusal exhibit a protective effect in about 35% of animals when acutely administered. After chronic treatments (5 days), the effect of triflusal (60% protection) was superior to that of ASA (27% protection) (p less than 0.01).

[Persistency of serum antibodies against Entamoeba histolytica]

With the purpose to determine the duration of serum antibodies against E. histolytica by means of the contraimmunoelectrophoresis technique, 31 patients with the diagnosis of intestinal or liver invasive amebiasis were included in this study. In 92.3% of the 13 patients subjected to transversal study, no specific antibodies were found from 10 to 24 months after the occurrence of amebic disease. In 64.7% of 17 children with liver amebiasis who were studied longitudinally, no serum antibodies were found between 4 to 10 months after the disease. The possible factors involved in the varaibility of the duration of serum antibodies against E. histolytica are discussed.