Cytologic and ultrastructural findings of a peculiar alteration in cervical cells from patients with human papillomavirus infections

Inclusion bodies were previously found in Papanicolaou smears of patients infected by the human papillomavirus (HPV). To ascertain their origin, 12 biopsies from patients with colposcopic evidence of papillomatous lesions were studied by cytology and electron microscopy. In several instances, koilocytotic atypias and electron-dense masses included within epithelial cells were observed. Some of these epithelial cells appeared to be surrounded by other cells in a sort of concentric arrangement. The electron-dense masses were composed of intermediate filaments, vacuoles and electron-dense material. They seemed to be dyskeratotic cells. They can be compared with apoptotic bodies and may be related to a disturbance of the involucrin expression caused by the HPV infection.     

Survival of patients with malignancy-associated effusions

For a better understanding of the prognosis after the onset of a malignancy-associated effusion in patients known or subsequently shown to have cancer, survival time was compared with the findings and the date of the first cytologic diagnosis of an effusion. The number of patients studied was 254; 171 had a pleural and 83 a peritoneal effusion. The average survival time was 25.5 weeks, which was about equal for both sites of effusions. After two years, only 6% of all patients were alive. When the cytologic diagnosis of the effusion was "malignant," only 4% survived after two years; when the cytologic diagnosis was "suspicious for malignancy" and "nonmalignant," these figures were 5% and 7%, respectively. This indicates that a cytologic diagnosis of benign or nonmalignant is not a good indicator of a better prognosis in cancer patients for whom benign causes of the effusion have been excluded. There appeared to be a prognostic relationship between the length of the interval from the initial diagnosis of cancer to the time of examination of the first sample of the effusion: a longer interval was correlated with a better survival. When survival time was viewed in relation to therapy, patients whose pleural effusions were only treated by aspiration were found to have a particularly short average survival (13.9 weeks).     

The molecular basis for Duchenne versus Becker muscular dystrophy: Correlation of severity with type of deletion

About 60% of both Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) is due to deletions of the dystrophin gene. For cases with a deletion mutation, the "reading frame" hypothesis predicts that BMD patients produce a semifunctional, internally deleted dystrophin protein, whereas DMD patients produce a severely truncated protein that would be unstable. To test the validity of this theory, we analyzed 258 independent deletions at the DMD/BMD locus. The correlation between phenotype and type of deletion mutation is in agreement with the "reading frame" theory in 92% of cases and is of diagnostic and prognostic significance. The distribution and frequency of deletions spanning the entire locus suggests that many "in-frame" deletions of the dystrophin gene are not detected because the individuals bearing them are either asymptomatic or exhibit non-DMD/non-BMD clinical features.     

Catabolite repression of the synthesis of inducible polygalacturonase and pectinesterase byAspergillus niger sp.

Several recent reports have described large numbers of monoclonal antibodies that cross-react with toxins A and B ofClostridium difficile; this suggests that the toxins share major epitopes. Our results show that monoclonal antibodies (MAb) against other antigens bind nonspecifically to both toxins. Therefore, we believe that the cross-reacting MAb bind by this manner and not by a true immune reaction.     

Interferon inhibits the accumulation of glycerol phosphate dehydrogenase mRNA in oligodendrocytes and C6 cells

We investigated the effect of rat interferon-/ (IFN) on the expression of glycerol phosphate dehydrogenase (E.C.1.1.1.8; GPDH), in both C6 cells and pure cultures of oligodendrocytes. IFNs are naturally produced inhibitors of cell growth that can also affect differentiated cell functions. GPDH is a biochemical marker for oligodendrocytes and is known to be developmentally regulated and steroid inducible. GPDH activity is induced by hydrocortisone (HC) 3.5 fold in C6 cells and 5 fold in oligodendrocytes compared to untreated cultures. A pretreatment of these cells with 75 U/ml of rat IFN-/ resulted in an inhibition of the HC induction of GPDH enzymatic activity by 50% and 40% in C6 cells and oligodendrocytes respectively. We also found that IFN impaired the accumulation of GPDH mRNA in both cell types. These results demonstrate that IFNs are capable of modifying the cellular response to hormones in cells of neuroepithelial origin, and suggest the possibility that IFNs may be able to influence the development and function of the brain.Special issue dedicated to Dr. Paola S. Timiras     

Structure of the bovine eye lens gamma s-crystallin gene (formerly beta s)

The organization of a number of crystallin genes has already been resolved. One of the remaining genes of which the structure was hitherto unknown is the gamma s gene (formerly beta s). We determined the complete sequence of the bovine gamma s-crystallin-coding gene, apart from the middle region of the first intron. Since it contains three exons and two introns, we conclude that the former beta s, also at the gene level is gamma-crystallin-like. However, it is located on chromosome 3, in contrast to other gamma genes which occur in tandem on the human chromosome 2.     

Detection and identification of FaeC as a minor component of K88 fibriilae of Escherichia coli

A tribrid gene containing ompF, faeC, and lacZ sequences was constructed by subcloning a large central segment of the K88ab gene encoding the fibrillar subunit-like protein FaeC into the open reading frame expression vector pORF2. The resulting tribrid protein was isolated and used to raise antibodies against the FaeC protein. These antibodies were then used for the detection and subcellular localization of the FaeC protein in Escherichia coli harbouring the K88ab-encoding plasmid pFM205 or mutant derivatives. Immunoblotting of subcellular fractions and of purified fibrillae, and agglutination experiments using whole cells revealed that the FaeC protein is present in the periplasm and as a minor component in the K88ab fibrillae. FaeC was also detected in purified K88ac and K88ad fibrillae. Immunoelectron microscopy confirmed the presence of FaeC in K88ab fibrillae, particularly at the tips of the longer fibrillae.