Breast ptosis. Classification and summary of surgical indications]

A general classification of ptotic breasts is proposed by the author in four main groups. 1) Precocious ptotic breasts including ptosis because of anomalies of skin elasticity and primary morphological ptotic aspects of the breast. 2) Ptotic breast as a result of excess of volume due to early hyperplasia, because of excess weight (around puberty, around pregnancy, around menopause). 3) Acquired ptotic small or long breast by fibrous retraction, or after weight loss. 4) Asymmetric ptotic breast, either primary, presenting at puberty or secondary presenting around pregnancy or after weight variations, or iatrogenic. An approach to the morphological analysis of each type of ptosis includes evaluation of skin quality, glandular density, relation between both. The role of weight stability is also discussed before a brief summary of the author's choice of techniques.     

Solitary bronchioloalveolar carcinoma: CT criteria

The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.     

Effect of interferon on two human choriocarcinoma-derived cell lines

Two cell lines derived from human choriocarcinomas (HCCM-5 and BeWo) are resistant to several biological effects of human interferon such as inhibition of VSV multiplication and inhibition of cell growth, but they develop a normal antiviral activity against EMCV. Nevertheless, in both cell lines, 2-5A synthetase and protein kinase are induced by IFN. 2-5A-dependent endonuclease can be measured by two independent methods and 2-5A itself is detected at least in poly(rI):poly(rC)- and IFN-treated BeWo cells. This is another example of two cell lines that are partially, with respect to the antiviral effect toward VSV, and totally, with respect to the anticellular effect, refractory to IFN treatment, although all the known elements of the 2-5A system are present.     

Differential effects of pentoxifylline on the production of tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) by monocytes and T cells.

Pentoxifylline (PTX) is a methylxanthine compound known to inhibit the production of tumour necrosis factor-alpha (TNF-alpha) by monocytic cells. In this study, we found that PTX differentially regulates the production of TNF-alpha and interleukin-6 (IL-6). Indeed, PTX at high concentrations triggers the production of IL-6 but not of TNF-alpha by peripheral blood mononuclear cells (PBMC). Further experiments indicated that monocytes are responsible for this PTX-induced IL-6 production. When PBMC were stimulated with LPS, PTX was found to inhibit the secretion of TNF-alpha as well as the accumulation of TNF-alpha messenger RNA (mRNA). In contrast, no inhibitory effect was observed on the induction of IL-6. Similar results were obtained when PBMC were stimulated with OKT3 monoclonal antibody (mAb). In addition, the in vivo administration of PTX in transplant patients receiving the first dose of OKT3 allowed to decrease the systemic release of TNF-alpha but not of IL-6. Since monocytes represent a major source of TNF-alpha and IL-6 in these settings, additional experiments were performed in vitro on purified T cells stimulated with the CLB-T3/3, an anti-CD3 mAb which does not require the presence of accessory cells to activate T cells. In this system, PTX was found to inhibit the secretion of both TNF-alpha and IL-6 by T cells. We suggest that cAMP could be involved in these differential effects of PTX on production of TNF-alpha and of IL-6.     

Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP)

The gene for the most frequent from of X-linked retinitis pigmentosa (XLRP), RP3, has been assigned by genetic and physical mapping to a segment of less than 1000 kbp, which is flanked by the marker DXS1110 and the ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have screened the DNA of 30 unrelated patients with XLRP by employing a representative set of YAC-derived DNA fragments that were generated by restriction enzyme digestion and PCR amplification. In one of these patients, a 6.4 kbp microdeletion was detected which was not present in the DNA of 444 male controls. A cosmid contig spanning the deletion was constructed and used to isolate cDNAs from retina-specific libraries. Exons corresponding to these expressed sequences as well as other putative exons were identified by sequencing more than 30 kbp of the critical region. So far, no point mutations in these putative exon sequences have been identified.      

Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1

The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X- linked RP (XLRP), has been mapped previously to a chromosome interval of less than 1000 kbp between the DXS1110 marker and the OTC locus at Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization (YRH)', we have recently identified a small XLRP associated microdeletion in this interval, as well as several putative exons including the 3' end of a gene that was truncated by the deletion. cDNA library screening and sequencing of a cosmid centromeric to the deletion has now enabled us to identify numerous additional exons and to detect several point mutations in patients with XLRP. The predicted gene product shows homology to RCC1, the guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our findings suggest that we have cloned the long-sought RP3 gene, and that it may encode the GEF of a retina-specific GTP-binding protein.      

Spontaneous and induced recovery of visual hemineglect during cooling inactivation of middle suprasylvian cortex in the cat

The purpose of the present study was to observe recovery of orienting deficits during unilateral and bilateral cooling inactivation of the middle suprasylvian (MS) cortex. Unilateral MS cooling resulted in a contralateral hemineglect (no orienting responses towards stimuli in the contracooled hemifield) that spontaneously recovered within less than 40 min of continued cooling. Moreover, the brain changes responsible for this recovery were partially retained and cumulated over successive cooling days. Bilateral MS cooling indicated that recovery of neglect can be induced by a restoration of the imbalance between activity levels of structures in both hemispheres and revealed an interaction between spontaneous and induced recovery of neglect. These results show that considerable changes may occur in the brain during cooling for rather short periods. Possible explanations for these changes are discussed.     

Comprehensive mutational scanning of the p53 coding region by two- dimensional gene scanning

A comprehensive mutational scanning test for the p53 coding region based on multiplex PCR and two-dimensional DNA electrophoresis was designed and evaluated. In a 2-step multiplex PCR, the p53 coding region (exons 2-11) was amplified as a single 8646-bp fragment by long- distance PCR in step one. This fragment served as a template for the subsequent co-amplification of the individual exons in two multiplex groups in step two. The multiplex products were then separated, first on the basis of size in non-denaturant polyacrylamide gels and then on the basis of sequence by denaturing gradient gel electrophoresis (DGGE). Primers for optimal PCR, melting behavior and 2-D gel distribution were designed using a recently developed computer program. The resulting two-dimensional gene scanning (TDGS) test was evaluated by screening, in a blinded fashion, 29 coded DNA samples from Li- Fraumeni syndrome patients with previously identified germline mutations. All mutations were correctly detected. This assay provides an accurate, cost-effective and non-radioactive method for simultaneous mutational scanning of all p53 coding exons.