[Iris metastasis of bronchial carcinoma: a case report]. / Métastase de l'iris d'un adénocarcinome bronchique: à propos d'un cas.

We report the observation of a 55-year-old man in subtotal remission of a bronchial T2 N2 M1 adenocarcinoma. He consulted for left ocular redness, attributed to a foreign body. The patient presented a left iridal metastasis of bronchial carcinoma, a left frontal cerebral metastasis, and mediastinal evolutionary recovery. External radiotherapy of 30 Gy in ten fractions was immediately begun, followed by second-line chemotherapy. Local anatomical and functional recovery was fast. The patient then required two external radiotherapy courses on new extraocular lesions. The patient died 10 months after the ocular metastasis diagnosis. In the event of iridal metastasis, it is necessary to carry out a complete examination of both eyes, to question the patient, to search for a primary tumor and other metastases, and to rapidly implement radiotherapy of the entire ocular sphere (30 Gy in ten fractions).

[Nephelometry or turbidimetry for the determination of albumin, ApoA, CRP, haptoglobin, IgM and transthyretin: which choice?]. / Turbidimétrie ou néphélémétrie: quel choix pour les dosages de l'albumine, l'ApoA, la CRP, l'haptoglobine, l'IgM et la transthyrétine?

Nephelometry, which is considered as the reference method for serum proteins determination requires a specific equipment. The majority of protein determinations are therefore carried out on biochemistry automats using turbidimetry. The objective of a CNBH group (Collège national de biochimie des hôpitaux) was to compare nephelometry and turbidimetry for 7 automats: 2 nephelometers, the BN Prospec (Dade-Behring) and Immage (Beckman-Coulter) and 5 biochemistry systems using turbidimetry, the Integra and Modular (Roche Diagnostics), the LX20 (Beckman-Coulter), RXL (Dade-Behring) and AU (Olympus). The study was based on the determination of sera collections (albumin, ApoA, CRP, haptoglobin, IgM, transthyretin) of 140 samples each: 110 limpid samples and 30 samples called HLI (hemolytic, lipemic or icteric). Fifteen hospitals took part to this work. An ANOVA analysis on limpid samples and quality control sera concluded to an "automat" effect for the 6 tested proteins but did not show a "method" effect, (i.e. nephelometry versus turbidimetry). On the other hand, the transferability of the results was expected to be better and an effort on the choice of the antibodies and the standardization procedures should be made.

Piezoelectric diaphragm for vibration energy harvesting.

This paper presents a technique of electric energy generation using a mechanically excited unimorph piezoelectric membrane transducer. The electrical characteristics of the piezoelectric power generator are investigated under dynamic conditions. The electromechanical model of the generator is presented and used to predict its electrical performances. The experiments was performed with a piezoelectric actuator (shaker) moving a macroscopic 25 mm diameter piezoelectric membrane. A power of 0.65 mW was generated at the resonance frequency (1.71 kHz) across a 5.6 kOmega optimal resistor and for a 80 N force. A special electronic circuit has been conceived in order to increase the power harvested by the piezoelectric transducer. This electrical converter applies the SSHI (synchronized switch harvesting on inductor) technique, and leads to remarkable results: under the same actuation conditions the generated power reaches 1.7 mW, which is sufficient to supply a large range of low consumption sensors.

[A proposal of ready-made interpretative comments applicable to serum protein electrophoresis]. / Proposition de commentaires interprétatifs prêts à l'emploi pour l'électrophorèse des protéines sériques.

Zone electrophoresis for separation and quantification of serum proteins is useful in numerous pathological situations to make clinical diagnostics, to follow the evolution of a disease or to evaluate the efficiency of a treatment. The biologist must apply professional recommendations according to the official nomenclature of biological analysis. He must attach a comment to each result in order to help the physician to perform the best interpretation of the results. To answer those needs, a work of standardization of these comments has been realized by a group of biologists. They are members of the national college of biologists (CNBH). All the commentaries are assembled in a thesaurus which could be a base of ready-made comments, favouring the interpretation of serum protein electrophoresis results.

Specific protein-protein interaction between basic helix-loop-helix transcription factors and homeoproteins of the Pitx family.

Homeoproteins and basic helix-loop-helix (bHLH) transcription factors are known for their critical role in development and cellular differentiation. The pituitary pro-opiomelanocortin (POMC) gene is a target for factors of both families. Indeed, pituitary-specific transcription of POMC depends on the action of the homeodomain-containing transcription factor Pitx1 and of bHLH heterodimers containing NeuroD1. We now show lineage-restricted expression of NeuroD1 in pituitary corticotroph cells and a direct physical interaction between bHLH heterodimers and Pitx1 that results in transcriptional synergism. The interaction between the bHLH and homeodomains is restricted to ubiquitous (class A) bHLH and to the Pitx subfamily. Since bHLH heterodimers interact with Pitx factors through their ubiquitous moiety, this mechanism may be implicated in other developmental processes involving bHLH factors, such as neurogenesis and myogenesis.

NeuroD1/beta2 contributes to cell-specific transcription of the proopiomelanocortin gene.

NeuroD1/beta2 is a basic helix-loop-helix (bHLH) factor expressed in the endocrine cells of the pancreas and in a subset of neurons as they undergo terminal differentiation. We now show that NeuroD1 is expressed in corticotroph cells of the pituitary gland and that it is involved in cell-specific transcription of the proopiomelanocortin (POMC) gene. It was previously shown that corticotroph-specific POMC transcription depends in part on the action of cell-restricted bHLH factors that were characterized as the CUTE (corticotroph upstream transcription element) (M. Therrien and J. Drouin, Mol. Cell. Biol. 13:2342-2353, 1993) complexes. We now demonstrate that these complexes contain NeuroD1 in association with various ubiquitous bHLH dimerization partners. The NeuroD1-containing heterodimers specifically recognize and activate transcription from the POMC promoter E box that confers transcriptional specificity. Interestingly, the NeuroD1 heterodimers activate transcription in synergy with Ptx1, a Bicoid-related homeodomain protein, which also contributes to corticotroph specificity of POMC transcription. In the adult pituitary gland, NeuroD1 transcripts are detected in POMC-expressing corticotroph cells. Taken together with the restricted pattern of Ptx1 expression, these results suggest that these two factors establish the basis of a combinatorial code for the program of corticotroph-specific gene expression.

Heterodimeric retinoic acid receptor-beta and retinoid X receptor-alpha complexes stimulate expression of the intercellular adhesion molecule-1 gene.

Human intercellular adhesion molecule-1 (ICAM-1), a specific ligand for the leukocyte-function associated antigen-1 and for Mac-1, plays an important role in immune responses. ICAM-1 expression is regulated by various proinflammatory cytokines, phorbol myristate acetate, and retinoic acid. In this study, we investigated the mechanisms of transcriptional control involved in the stimulation of ICAM-1 gene expression by retinoic acid in Cos-1 cells. Deletion mutant analysis provided evidence that a region located between -393 and -176 from the translational start site is critical to retinoic acid stimulation of luciferase activity. This region harbors the consensus sequence for a retinoic acid-responsive element (RARE) 5'-GGGTCATCGCCCTGCCA-3'. The Smal(-270)/Smal (-178) fragment containing this element conferred appropriate retinoic acid responsiveness to an enhancerless SV40 promoter. Cotransfection of expression vectors encoding the retinoic acid receptor alpha, beta, or gamma and retinoid X receptor alpha with reporter plasmids harboring the putative RARE demonstrated that the ICAM-1 gene is regulated by retinoic acid in a retinoic acid receptor beta/retinoid X receptor alpha-dependent fashion. Electrophoretic mobility shift assays showed that ICAM-1 and ADH3 RARE, a well-characterized RARE, display the same band shift pattern, bind retinoic acid receptor beta and retinoid X receptor alpha, and are mutually competitive.

Immunohistochemical localisation of macromolecules of the basement membrane and extracellular matrix of human gliomas and meningiomas.

The distribution of type I, III, IV and V collagen in 35 gliomas and 20 meningiomas was studied by indirect immunofluorescence staining. In addition, the presence of fibronectin (FN) and laminin (LN) is also reported. In gliomas expression of type IV collagen and LN was found in the vessel walls and associated with the endothelial glomerulus-like proliferations. FN and type V collagens were located in proliferating vessel walls in a pattern corresponding both to the basement membrane and the perivascular matrix around the vessels. In the extracellular matrix of grade III and IV gliomas occasional faint intercellular fluorescence was also observed with both FN and type V collagen. Type I and III collagens were localised in the vessel walls and in the perivascular connective sheet. Glioma cells did not express any of the antigens investigated. In meningiomas, type IV and V collagens, LN and FN were found in vessel walls, whorls formations and psammoma bodies. These stainings support the hypothesis of a vascular origin of these psammoma bodies which were only found in syncytial and transitional meningiomas. Both type I and III collagens were detected in the perivascular connective tissue. In general, meningioma cells and extracellular matrix did not express any of these molecules, except in transitional meningiomas where occasional fluorescence was observed in extracellular matrix with type V collagen and FN.

Immunohistochemical localization of macromolecules of the basement membrane and the peritumoral stroma in human laryngeal carcinomas.

Forty laryngeal carcinomas were studied by immunofluorescence with specific antisera against components of the basement membrane (type IV collagen and laminin) as well as antisera against connective tissue antigens (type V collagen and fibronectin). The basement membrane surrounding well-differentiated squamous cell carcinomas showed an appearance similar to that seen beneath normal epithelium. In contrast, marked alterations of the basement membrane were constantly observed around infiltrating and poorly-differentiated carcinomas. The staining of connective tissue components in most cases was as intense in carcinomas as in normal laryngeal mucosa. The use of antibodies to basement membrane components may help to elucidate the mechanism of invasion of connective tissues by malignant cells.

Effect of oxy radicals on several types of collagen.

Fibrils of collagen reconstituted in vitro by dialysis against sodium formate are exposed to free oxy radicals generated by three different systems: (i) xanthine oxidase + hypoxanthine, (ii) gamma-rays originating from a cobalt bomb; (iii) pulse radiolysis in a particle accelerator. A degradation of the collagen fibres is demonstrated by determination of the amount of hydroxyproline-containing peptides in the supernatant after incubation. Types I and III collagen are sensitive to the effect, whereas type V collagen is not. The effect persists when collagen is specially delipidated.

Distribution of type IV collagen in benign and malignant epithelial proliferations. An indirect immunofluorescence study on the breasts, the lungs, and the skin.

The distribution of type IV collagen in benign and malignant epithelial proliferations of the breasts, the lungs, and the skin was studied by an indirect immunofluorescence technique using specific antiserum. In benign lesions of the breasts, the staining for type IV collagen was present in all vascular and glandular basement membranes. In basal cell carcinoma of the skin, the basement membrane labeling was also found to be continuous. In malignant lesions of the breasts, the lungs, and the skin, staining for type IV collagen was seen only around well-differentiated glandular structures and in close contact to basal epidermal cells. This staining appeared as an irregular network. Of particular interest was the localization of type IV collagen in non-infiltrating lesions of the breasts and the bronchi where discontinuity in the basement membrane staining was observed. In contrast, there were no disruptions of basement membrane labeling in skin senile keratosis and in Bowen's disease. We conclude that the loss of type IV collagen seen in malignant proliferations in our study is related to overt or potential tumor cell infiltration and aggressiveness.

A method for the evaluation of 3-hydroxyproline in the urine.

After hydrolysis of the urine by 6 M HCl, 3-hydroxyproline is purified from many interfering substances by 2 steps of chromatography on Dowex 1 X8 resin equilibrated first in the acetate form and secondly in the OH- form. The amino acid is finally evaluated by chromatography on Dowex 50 M82 resin in a Beckman multichrom amino acid analyzer. In 23 normal adult subjects the mean level was 12.5 +/- 3.5 mumol/24 h. In 8 normal children the level was 6.0 +/- 5 mumol/24 h and in 8 teenagers 15.2 +/- 2.85 mumol/24 h. The ratio of 3-hydroxyproline to 4-hydroxyproline seems indicative of a semiological value of this evaluation in cases of basement membrane collagen deterioration.