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A Devos

Publications and source records attributed to A Devos.

At least 19 recordsLinked to original sources
PubMed2001

Evidence of laser-wavelength effect in picosecond ultrasonics: possible connection with interband transitions.

We have studied the effect of wavelength change on picosecond acoustic pulses generated using a femtosecond laser. For the first time, we show that the pulse shape can be strongly influenced by the laser wavelength. The results are in excellent agreement with a calculation based on a thermoelastic model which connects them to significant changes in the piezo-optical constants. There are similarities between the present study and stress modulation spectroscopy, which allows us to ascribe the observations to interband transitions and suggests thus a new potentiality of picosecond ultrasonics.

Journal Article↗
PubMed1999

Leptomeningeal metastases from ethmoid sinus adenocarcinoma: clinico-radiological correlation.

A patient with sinonasal adenocarcinoma is presented with leptomeningeal metastases affecting multiple cranial nerves and spinal nerve roots. Head and neck cancer is known to be an extremely rare source for leptomeningeal metastatic spread. The cranial nerves, the spinal cord and roots and the cerebral hemispheres can be affected in case of leptomeningeal metastatic spread. Examination of the CSF is the hallmark of the diagnosis if leptomeningeal metastatic spread is suspected, but this case illustrates that the combination of specific clinical features on one hand and specific lesions on the Gd-enhanced T1-weighted MRI study on the other hand is reliable enough to make a presumed diagnosis if the CSF analysis remains negative. We suggest that in our patient direct leptomeningeal spread occurred through the cribriform plate to the CSF, followed by further spread in a gravity dependent way.

Adenocarcinoma↗
PubMed1997

A randomized phase II study of BB-10010: a variant of human macrophage inflammatory protein-1alpha for patients receiving high-dose etoposide and cyclophosphamide for malignant lymphoma and breast cancer.

Macrophage inflammatory protein-1alpha (MIP-1alpha) is a chemokine that can inhibit the cell cycle progression of both primitive haemopoietic and epidermal progenitor cells. This property could potentially be exploited to attenuate both the myelosuppressive effects of chemotherapy as well as mucositis. We evaluated both the biological and clinical effects of BB-10010, a genetically engineered variant of MIP-1alpha, in patients with malignant lymphoma or breast cancer receiving high-dose etoposide (VP 3.6 g/m2) and cyclophosphamide (Cy 200 mg/kg). 52 patients were randomized to one of three cohorts. Cohort A received no BB-10010; cohorts B and C received 10 microg/kg and 100 microg/kg of BB-10010, respectively. All patients received post-chemotherapy G-CSE BB-10010 was well tolerated. There were no significant differences between groups in recovery to an ANC > 0.5 x 10(9)/l, 1 x 10(9)/l or 1.5 x 10(9)/l, the number of days with an ANC < 0.5 x 10(9)/l, days to a platelet count > 50 x 10(9)/l or 100 x 10(9)/l, or the incidence and severity of mucositis. There was no evidence of any effect of BB-10010 on colony-forming cell (CFC) or long-term culture-initiating cell (LTC-IC) mobilization, cycling activity in the marrow or on chemotherapy-induced changes in CFC or LTC-IC number both of which were in the normal range by 22 d after completion of the chemotherapy. To our knowledge this is the first report of a myelointensive regimen having no apparent long-term effect on the LTC-IC compartment. In summary, BB-10010 is safe when used in patients receiving high-dose therapy but has no effect on reducing the toxicity of such therapy.

Adolescent↗
PubMed1997

Identification of a functional androgen-response element in the exon 1-coding sequence of the cystatin-related protein gene crp2.

Two hormone-responsive segments, one in the region of the promoter and one in intron 1, are identified in two homologous androgen-regulated and differentially expressed rat genes encoding the cystatin-related proteins (CRPs). Footprint analysis with the androgen receptor (AR) DNA-binding domain on the promoter-containing fragments reveals an AR-binding site downstream of the transcription start point in the crp2 gene (ARBSd/crp2, +40/+63). It displays an androgen response element-like sequence motif 5'-AGAAGAaaaTGTACA-3' and overlaps with the ATG translation start codon. A double-stranded oligonucleotide containing this sequence forms a DNA-protein complex with the full-length AR synthesized by vaccinia, as seen in band shift assays. Additional AR-binding sites, ARBSu/crp1 and ARBSu/crp2, occur 5' upstream of the transcription start point and are located at an identical position (-142/ -120) in crp1 and crp2. The AR affinity for these two slightly different sequence motifs is relatively weak. The biological function of all three AR-binding sites as transcription control elements has been studied. The ARBSd/crp2 element clearly shows androgen-response element characteristics. The contribution of the common upstream element to the androgen-dependent control of reporter gene transcription is less clear. The transcription of a reporter gene construct containing the crp2 footprint fragment crp2F (-273/+88) is hormonally regulated as determined by transfection into the human breast cancer cell line T-47D. Androgens, but also glucocorticoids, efficiently stimulate steroid-dependent transcription of the chloramphenicol acetyltransferase gene. Mutation of the 5'-TGTACA-3' sequence in ARBSd/crp2 destroys the AR binding and abolishes the androgen-dependent synthesis of chloramphenicol acetyltransferase. A large fragment derived from intron 1 of the crp1 and crp2 gene can also provide the androgen-dependent transcription of chimeric constructs in T-47D cells. However, the induction measured is less than the one observed with crp2F (-273/+88), and this activity seems to reside in several subfragments that each display a low but consistent androgen responsiveness.

Androgens↗
PubMed1996

The androgen-specific probasin response element 2 interacts differentially with androgen and glucocorticoid receptors.

The nuclear receptors constitute a large family of transcription factors characterized by a well conserved DNA-binding domain. The receptors for glucocorticoids, progestins, mineralocorticoids, and androgens constitute a subgroup because they bind in vitro with high affinity to DNA elements containing a partial palindrome of the core sequence 5'-TGTTCT-3'. In vivo, however, the corresponding steroids differentially regulate the expression of their target genes, even when more than one receptor type is present in a particular cell. The DNA-binding domains of the androgen and of the glucocorticoid receptors bind most androgen response elements with similar relative affinities. In contrast, one element (5'-GGTTCTTGGAGTACT-3') which was recently described in the promoter region of the probasin gene selectively interacts with the DNA-binding domain of the androgen receptor and not with that of the glucocorticoid receptor. From studies with chimeric elements, it can be deduced that it is the left subsequence 5'-GGTTCT-3' which excludes the glucocorticoid receptor domain from binding. In co-transfection experiments where the ARE of the C3(1) gene is responsive to both androgens and glucocorticoids, the probasin element is induced only by androgens and not by glucocorticoids. The existence of response elements which are recognized preferentially by the androgen receptor provides yet another possible mechanism to explain the differences of the in vivo effects between androgens and other steroids of the subgroup.

Androgen-Binding Protein↗
PubMed1996

Androgens transcriptionally regulate the expression of cystatin-related protein and the C3 component of prostatic binding protein in rat ventral prostate and lacrimal gland.

In this report, it is demonstrated that the C3 component of prostatic binding protein (PBP) is also expressed and androgen regulated in the exorbital lacrimal gland, as shown previously for cystatin-related protein (CRP), another abundant secretory protein from the ventral prostate. The presence of C3 messenger RNA (mRNA) could be demonstrated by both Northern blot hybridization and PCR amplification and sequencing. The mRNAs encoding the C1 and C2 components of PBP, however, were undetectable. At the protein level, the C3 component in the lacrimal gland is glycosylated and linked by disulfide bridges to a new 10-kDa component not reacting with the PBP antiserum. As shown previously for CRP, the expression of C3 in the lacrimal gland requires the simultaneous presence of androgens and a functional androgen receptor. The effects of castration and androgen treatment on CRP and C3 mRNA concentrations were studied by Northern blot and dot blot hybridization; effects on transcription rates were determined by nuclear run-on assay. Two days after castration, the relative abundance of CRP mRNA had declined significantly (P < 0.01) to 10.5 +/- 1.5% (+/-SEM) of precastration levels in the prostate and to 14.5 +/- 8.0% in the lacrimal gland; the transcription rates declined to 14.3% and 10.0%, respectively. The C3 mRNA level and transcription rate in the prostate showed a more moderate decrease (P < 0.05) to 40.6 +/- 8.5% and 41.7%, but were hardly measurable in the lacrimal gland. Androgen administration resulted in a rapid increase in the transcription rates, which reached or exceeded control levels after 6-9 h of treatment and clearly preceded the increase in mRNA levels. It is concluded that the lacrimal gland, which can be studied conveniently in female and long term androgen-depleted animals offers a suitable model for the study of androgen-regulated gene expression.

Analysis of Variance↗
PubMed1995

The genes coding for rat cystatin-related prostate protein (Cstrp) map to chromosome 3q41.

Two genes encoding rat cystatin-related prostate protein (Cstrp), previously called CRP (Devos et al., 1993), were mapped to chromosome 3q41 by fluorescent in situ hybridization. The results were confirmed using a panel of mouse-rat hybrids that segregate rat chromosomes. Analysis of genomic DNA indicates that the Cstrp locus comprises probably more than three very similar genes.

Animals↗
PubMed1993

Structure of rat genes encoding androgen-regulated cystatin-related proteins (CRPs): a new member of the cystatin superfamily.

Cystatin-related proteins (CRPs) are abundant androgen-regulated secretory glycoproteins that are specifically synthesized in the ventral prostate and lachrymal gland of the rat. Two complete 6-kb genes, Crp1 and Crp2, have been cloned and characterized. They are differentially expressed and encode slightly different proteins. The genes each contain four exons which are interrupted by large introns. An alignment of their sequences demonstrates an overall homology of 90%. The 3' end of a third gene, Crp3, from which only a 1.5-kb fragment was isolated, displays a sequence identity of 84%. These data indicate the existence of a Crp multigene family. The 5' flanking regions of Crp1 and Crp2 are highly homologous and contain a GATAAA sequence 29 nt upstream from the transcription start point. This TATA-box-like element is also found in the promoters of the genes encoding cystatin type-2 proteins. No other recognizable transcription control elements can be detected. Potential binding sites (ARE) for the androgen receptor are scattered throughout the entire genes. The exon/intron organization of the genes encoding CRPs, the size of the exons and their encoding amino acid sequences exhibiting a characteristic spacing of the Cys residues are structural elements displaying a remarkable similarity with the corresponding elements in the genes encoding cystatin type-2 proteins. CRPs must therefore belong to the cystatin superfamily. However, due to their additional domain encoded in an extra exon 2, CRPs must be classified as a new family, type 5.

Amino Acid Sequence↗
PubMed1993

An effect of androgens on the length of the poly(A)-tail and alternative splicing cause size heterogeneity of the messenger ribonucleic acids encoding cystatin-related protein.

The 22-kilodalton glycoprotein, expressed in the rat ventral prostate under the influence of androgens, is structurally a cystatin-related protein (CRP), as has been shown by copy DNA sequencing. In fact, two slightly different forms (CRP-1 and CRP-2) are expressed in the prostate; one of them (CRP-1) is also expressed in the exorbital lacrymal gland. In both glands, the CRP-1 messenger RNA (mRNA)s are androgen regulated. Moreover, androgens also influence the size of these mRNAs, which show marked heterogeneity (from 760-950 nucleotides). Indeed, the smaller forms are predominant in castrated animals, whereas the large forms are observed immediately after androgen induction. Hybridization with oligo(dT) followed by ribonuclease H treatment revealed that differences in length of the poly(A)-tail are responsible for this effect of androgens. Indeed, two well defined forms of CRP mRNA subsisted after removal of the poly(A)-tail by this treatment. In the less abundant shorter form (CRP-1 delta), 123 nucleotides are deleted by alternative splicing at the junction between the third and the fourth exon. The variant mRNA encodes a truncated protein, wherein the last 27 amino acids are replaced by a hydrophobic stretch of 8 amino acids. No alternative splicing was observed for the CRP-2 mRNA.

Alternative Splicing↗
PubMed1992

The 4.4-kilodalton proline-rich polypeptides of the rat ventral prostate are the proteolytic products of a 637-kilodalton protein displaying highly repetitive sequences and encoded in a single exon.

We have determined the complete sequence of the 637-kilodalton precursor for the proline-rich polypeptides (PRPs). This protein is encoded in one large exon of a single copy gene. The acidic precursor of 5761 residues comprises a signal peptide and three large domains displaying a high proline content (11-15%). The sequence of domain A (928 residues) is unique and contains several small clusters of acidic amino acids. Domain B (830 residues) exhibits seven tandem repeats, four of them displaying a strongly diverged sequence. In domain C (3914 residues) 39 units, of which only 8 are degenerate, occur in a tandem repeat. Their sequence of 100 amino acids shows a high structural similarity (76-92%) and contains all the PRP variants which are produced by specific proteolytic processing. The COOH-terminal part (35 residues) is basic. Two variant PRP-precursor alleles occur which slightly differ in the number of repeats in domain C. The high degree of sequence conservation within the repeat regions suggests that the gene presumably evolved by multiple amplification and dispersion of two internal segments. In the 5097-base pair genomic region 5' upstream from the translation start, several control elements for transcription are recognized. A potential binding site for the Sp1 factor (GGGCGG) separated by 47 nucleotides from an initiator motif, most probably elements of the promoter, is detected in the vicinity of the ATG codon. Several putative androgen response elements (TGTYCT) are found in the 5' adjacent region and far upstream two Alu type III repeats and two (CA)n repeats are located. These results provide the basis for a detailed study of the androgen-regulated and tissue-specific expression of the PRP-precursor gene.

Amino Acid Sequence↗
PubMed1987

[Virus excretion and changes in virulence of type 1 paramyxovirus of pigeons following passage through chickens].

Paramyxovirus type 1 of pigeons (strain PMV1-D) was transmitted by sequential contact over nine groups of SPF chicks. The first and last (9th) passages were made in 12-day-old SPF chicks, whereas the others were made in day-old chicks. Mortality was much higher in the last passage group than it was in the first group. None of the day-old chicks survived the PMV1-D infection. Increased virulence of PMV1-D for chickens following passages was also found to be present by the virus characterisation indexes, the EID50, the ICPI and the IVPI in particular.

Age Factors↗
PubMed1980

[Rendering plants in Belgium. A survey of their importance and significance (author's transl)].

Four rendering plants are responsible for the whole of the rendering processes in Belgium. The animal population is not equally spread over the country, there is a marked preponderance of the pig and poultry population in the northern part (fig 1 and 2), while cattle and horses are more equally spread. Per inhabitant about 6,5 kg cadaver and offal are rendered yearly. The offal remained relatively constant since 1970, on the contrary the weight of cadavers increased with about 50%, the pigs take the largest part of the increase (table 2). It is obvious that efforts are necessary to reduce drastically the mortality in pigs and poultry. Lowering of infection pressure in the environment could be one of the most effective measures to reduce the mortality in farm animals. On the other hand rendering plants have a specific hygienic role when only the destruction of animals infected with infectious agents submitted to legal regulations are taken in account (table 5).

Abattoirs↗
PubMed1976

The origin of urinary hydroxylysyl glycosides in Paget's disease of bone and in primary hyperparathyroidism.

The urinary excretion of glucosyl-galactosyl-hydroxylysine and of galactosyl-hydroxylysine were studied in Paget's disease of bone and in primary hyperparathyroidism. Both metabolites were increased in these diseases. Although glucosyl-galactosyl-hydroxylysine is not abundant in bone collagen, it is possible that a part of it originates from calcified tissue.

Alkaline Phosphatase↗
PubMed1976

Peptide-bound hydroxylysine and large polypeptides related to collagen synthesis.

About 10% of the urinary hydroxylysine is linked to peptides. There is no significant difference between the excretion of peptide-bound hydroxylysine and hydroxylysine measured in the non-dialysable fraction of the urine. Non-dialysable hydroxylysine is highly glycosylated and contains mainly glucosyl-galactosyl-hydroxylysine. It is concluded that the urinary peptide-bound hydroxylysine is present in the non-dialysable collagen polypeptides. Their unusual carbohydrate composition is discussed.

Collagen↗
PubMed1976

Cutaneous geotrichosis in the red flamingo (Phoenicopterus ruber).

In three flamingos (Phoenicopterus ruber), which died showing extensive necrotic inflammation of the skin of the webs and the legs, the presence of abundant mycelium and arthrospores was shown in the altered dermis and epidermis. From all the lesions Geotrichum Candidum was isolated in pure culture. Inoculation of suspensions of the fungus into domestic chickens and mice produced granulomas or more purulent nodules with central growth of abundant mycelium. From 20 of 28 experimental animals, G. candidum was reisolated from the lesions in pure culture 2 weeks after the inoculation. It is suggested that alteration of the skin by e.g., prolonged contact with pondwater, the presence of small wounds and the advanced age of the birds, acting as predisposing factors may be necessary in establishing this disease.

Animals↗