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M Moerman

Publications and source records attributed to M Moerman.

35 records · Page 2Linked to original sources
PubMed1998

Schwannoma of the tip of the nose: MRI.

We report a schwannoma with a rare location at the tip of the nose in a 20-year-old woman with an otherwise unremarkable medical history. The imaging findings underline the usefulness of MRI in narrowing down the differential diagnosis of masses in this region. Once the diagnosis was focussed on a neural origin of the mass, the exact nature of the tumour could not be predicted from the MRI, although the presence of a capsule on imaging studies as well as at operation suggested it was probably a schwannoma. A schwannoma must be considered when one encounters a sharply delineated mass at the tip of the nose, showing high signal on T2-weighted images and strongly contrast enhancement.

Adult↗
PubMed1998

Laryngeal embryonal rhabdomyosarcoma in a child: MRI appearance.

We report a rare case of a young girl with an embryonal rhabdomyosarcoma of the right aryepiglottic fold. Local disease recurrence, occurring 7 years after subtotal resection and adjuvant chemotherapy, was studied with plain radiography, CT and MRI. To the best of our knowledge, this is the first report illustrating the MRI characteristics of a laryngeal embryonal rhabdomyosarcoma in a child.

Child↗
PubMed1998

Primary sinonasal mucosal melanoma: three different therapeutic approaches to inoperable local disease or recurrence and a review of the literature.

Sinonasal melanoma is an uncommon disease with a bad prognosis and a high local recurrence rate. The use of radiotherapy in such conditions remains controversial. A review of the literature is presented in an attempt to answer some of the questions regarding therapeutic options. Data on incidence, aetiology, pathology and prognosis are also provided. Case studies are reported of three patients with sinonasal melanoma referred to our department in a relatively short time period and needing radiotherapy as a single treatment modality, using a conformal three-dimensional treatment technique. One patient was also treated with temporary 1251 seeds, while another was treated using intensity modulation. Both intensity modulation and temporary 1251 seeds are feasible techniques, providing satisfactory dose distributions encompassing the tumour volume while sparing critical structures. Surgery remains the treatment of choice for sinonasal melanoma. Radiotherapy should be used postoperatively and is a good alternative in cases of inoperable disease. Adjacent critical structures limit the radiation dose to the tumour area, especially when high fraction doses are used. Therefore, beam intensity modulation and 1251 seeds can be used to increase the tumour dose without exceeding the radiation tolerance of the surrounding structures.

Adult↗
PubMed1996

An introduction to computerised speech lab.

The need for standardised objective figures exists in speech pathology. This can be provided by a computerised technique, the computerised speech lab (CLS), which performs an acoustic analysis of the voice samples and gives objective figures of multiple parameters.

Acoustics↗
PubMed1994

The root epidermis-specific pea gene RH2 is homologous to a pathogenesis-related gene.

Two-dimensional gel electrophoresis of pea root and root hair proteins revealed the existence of at least 10 proteins present at elevated levels in root hairs. One of these, named RH2, was isolated and a partial amino acid sequence was determined from two tryptic peptides. Using this sequence information oligonucleotides were designed to isolate by PCR an RH2 cDNA clone. In situ hybridization studies with this cDNA clone showed that rh2 is not only expressed in root hairs, but also in root epidermal cells lacking these tubular outgrowths. During post-embryonic development the gene is switched on after the transition of protoderm into epidermis and since rh2 is already expressed in a globular pea embryo in the protoderm at the side attached to the suspensor, we conclude that the expression of rh2 is developmentally regulated. At the amino acid level RH2 is 95% homologous to the pea PR protein I49a. These gene encoding I49a is induced in pea pods upon inoculation with the pathogen Fusarium solani [12]. We postulate that rh2 contributes to a constitutive defence barrier in the root epidermis. A similar role has been proposed for chalcone synthase (CHS) and chitinase, pathogenesis-related protein that are also constitutively present in certain epidermal tissues.

Amino Acid Sequence↗
PubMed1993

Mastoiditis caused by atypical mycobacteria.

Three case reports of mastoiditis caused by atypical mycobacteria are discussed and a review of the world literature is given. Our aim is to focus the attention of the ENT specialist and the pediatrician on these pathological agents in unilateral recurrent otitis media. The case reports illustrate the importance of histologic and microbiologic examination. Difficulties in the differential diagnosis are mentioned. The therapy is slightly different from lymphadenitis caused by atypical mycobacteria because for mastoiditis we prefer the combination of surgery with medical treatment.

Child↗
PubMed1993

Lipo-oligosaccharides of Rhizobium induce infection-related early nodulin gene expression in pea root hairs.

This paper shows that lipo-oligosaccharides (Nod factors) synthesized by Rhizobium bacteria elicit the induction of infection-related early nodulin genes (PsENOD5 and PsENOD12) in pea root hairs. R. leguminosarum bv. viciae secretes a mixture of Nod factors containing a C18 fatty acid chain with 4 (C18:4) or 1 double bond (C18:1). Purified Nod factors harbouring either a C18:4 or a C18:1 acyl moiety induce the expression of the pea early nodulin genes, PsENOD5 and PsENOD12, but the kinetics of induction are different. The expression of both early nodulin genes is induced in a transient manner by the purified Nod factors while a mixture of the Nod factors extends the period during which these genes are expressed. In spite of the host-specific nature of the infection process, heterologous Nod factors of R. meliloti also induce the expression of PsENOD5 and PsENOD12 genes, though with a marked delay compared with the homologous compounds.

Base Sequence↗
PubMed1992

A hairy polyp of the middle ear and mastoid cavity.

A case of a 'hairy polyp', a dermoid tumor of the middle ear and the mastoid cavity is described, which is very unusual location. The radiological, surgical and histological features are discussed. Comment is made on the differentiation between dermoid cysts and teratomas and on the scarcity of both tumors in the area of the temporal bone.

Dermoid Cyst↗
PubMed1985

Expression of plant genes during the development of pea root nodules.

The expression of plant genes involved in the pea-Rhizobium symbiosis was studied by analysing mRNA from root nodules. The RNA was translated in vitro and the translation products were separated by two-dimensional gel electrophoresis. The results show differential expression of nodulin genes during root nodule development. One gene encoding N-40' is expressed at a significant level 5 days before the leghemoglobin genes. Most other nodulin genes are expressed more of less concomitantly with the leghemoglobin genes whereas the N-21 mRNA is only present late during the development. In the development of ineffective root nodules induced by infection with different nod+fix- mutants of R. leguminosarum all nodulin genes are expressed except for the N-21 gene. The results suggest that neither bacteroid development, heme excretion nor nitrogen fixation are essential for the induction of nodulin gene expression in the host plant. Further, it appears that the amount of leghemoglobin in ineffective nodules is regulated at a post-transcriptional level.

Electrophoresis, Gel, Two-Dimensional↗
PubMed1984

Cowpea mosaic virus VPg: sequencing of radiochemically modified protein allows mapping of the gene on B RNA.

A partial amino acid sequence of cowpea mosaic virus (CPMV) VPg radiochemically modified by chloramine-T and Bolton-Hunter reagent has been determined. VPg covalently bound to viral RNA chains (VPg-RNA) was iodinated with chloramine-T and Bolton-Hunter reagent to label tyrosine and lysine residues, respectively. [I]VPg-RNA was digested with nuclease P1 and the resulting [I]VPg-pU was purified by SDS-polyacrylamide gel electrophoresis and subjected to automated Edman degradation. Control experiments with chemically synthesized poliovirus VPg showed the feasibility of radiochemical microsequence analysis of protein that had been radiochemically modified by chloramine-T and Bolton-Hunter reagent. Analysis of CPMV [I]VPg-pU revealed the presence of tyrosine residues at position 12 and 14, and of lysine residues at position 3 and 20, respectively. In combination with Edman degradation of unlabeled CPMV VPg, which showed serine and arginine residues to be present at position 1 and 2, respectively, the data obtained allow the precise positioning of VPg within the 200 000 dalton (200 K) polyprotein encoded by CPMV B RNA and the prediction of its entire amino acid sequence. VPg is located at the COOH terminus of its 60 K, membrane-bound,precursor and proximal to the amino terminus of the protease-polymerase domain of the polyprotein. A processing scheme for the 200 K polyprotein is discussed in which Gln-Ser amino acid pairs act as the major signal for proteolytic cleavage.

Journal Article↗
PubMed1984

Evidence That the 32,000-Dalton Protein Encoded by Bottom-Component RNA of Cowpea Mosaic Virus is a Proteolytic Processing Enzyme.

Translation of middle-component RNA of cowpea mosaic virus in vitro produced two polypeptides of 95 and 105 kilodaltons (95K and 105K, respectively) with overlapping amino acid sequences, which were specifically cleaved by a protease encoded by the bottom-component RNA. The proteolytic cleavage was studied by the addition of antibodies raised against various bottom-component RNA-encoded proteins to extracts prepared from bottom-component RNA-inoculated cowpea protoplasts. Since antiserum to the 32K polypeptide efficiently inhibited the proteolytic activity of such extracts, although antiserum to VPg or to the 170K polypeptide did not, evidence was obtained which indicates that the 32K polypeptide represents the protease involved. Fractionation of proteolytically active extract by glycerol gradient centrifugation demonstrated that 32K polypeptides do not exist as free proteins but are aggregated to the bottom-component RNA-encoded 170K, 84K, 60K, or 58K polypeptides. Maximal proteolytic activity was observed for 32K polypeptides associated with 170K polypeptides, suggesting that the activity was unstable and confined to newly synthesized molecules.

Journal Article↗
PubMed1982

Expression of Middle-Component RNA of Cowpea Mosaic Virus: In Vitro Generation of a Precursor to Both Capsid Proteins by a Bottom-Component RNA-Encoded Protease from Infected Cells.

The expression of the middle-component (M) RNA of cowpea mosaic virus was studied by means of in vitro translation. In both the wheat germ extract and the rabbit reticulocyte lysate, M RNA was translated into two overlapping polypeptides of 95 and 105 kilodaltons. Incubation of these polypeptides with 30,000 x g supernatant fractions from cowpea mesophyll protoplasts inoculated with complete virus or with separate bottom (B) components alone resulted in extensive processing, yielding polypeptides of 60, 58, 48, and 47 kilodaltons. Similar proteolytic activity was found associated with the in vitro translation products from the bottom-component RNA, demonstrating that the protease present in infected cells is encoded by B RNA. Using antisera raised against the separate capsid proteins VP23 and VP37, it was shown that the 60-kilodalton cleavage product is the precursor to both capsid proteins. Cleavage of nascent 95- and 105- kilodalton polypeptides by the in vivo protease demonstrated that this capsid protein precursor is located C terminally within both polypeptides and that the synthesis of these two overlapping polypeptides is the result of two initiation sites on middle-component RNA. In addition, a second virus-induced proteolytic activity, capable of releasing VP23 from the 95- and 105-kilodalton polypeptides, was detected in leaves of infected plants, but not in infected mesophyll protoplasts. A model for the expression of the middle-component RNA is presented.

Journal Article↗
PubMed1982

Antibodies Against the Genome-Linked Protein VPg of Cowpea Mosaic Virus Recognize a 60,000-Dalton Precursor Polypeptide.

We have prepared a rabbit antiserum specifically directed against the genome-linked protein (VPg) of cowpea mosaic virus by injecting an hydrolysate of purified virion RNA. Using this antiserum as a probe in combination with "Western" (protein) blots of subcellular fractions of cowpea mosaic virus-infected cowpea (Vigna unguiculata) cells, we have detected a bottom component RNA-encoded, 60,000-dalton polypeptide which is membrane bound and presumably represents the immediate precursor of VPg.

Journal Article↗
PubMedDate not supplied

The relationship between nodulin gene expression and the Rhizobium nod genes in Vicia sativa root nodule development.

The role of the Rhizobium nod genes in the induction of nodulin gene expression was examined by analyzing nodules formed on vetch roots by bacterial strains containing only the nod region. Introduction of an 11-kb cloned nod region of the R. leguminosarum sym plasmid pRL1JI into sym plasmid-cured rhizobia conferred on the recipient strains the ability to induce nodules in which all nodulin genes were expressed. This proves that from the sym plasmid only the nod region is involved in the induction of nodulin gene expression. A transconjugant of Agrobacterium carrying the same nod region induces nodules in which only early nodulin gene expression is detected. Thus, the nod region is essential for the induction of early nodulin gene expression. In this case, nodule cytology may indicate that a defense response of the plant interferes with the induction of late nodulin gene expression. Indirect evidence is presented that indeed the Rhizobium nod genes are also in some way involved in the induction of the expression of late noduling genes. The combination between histological data and pattern of nodulin gene expression furthermore reveals a correlation between nodule structure and nodulin gene expression. This correlation may aid in speculations about the functions of nodulins.

Blotting, Western↗
PubMedDate not supplied

Phonosurgery in gender dysphoria.

A particular type of phonosurgery is voice change surgery in cases of gender dysphoria. This paper presents a review of the surgical techniques available for raising or lowering speaking fundamental frequency. A cricothyroid approximation to raise the vocal pitch is the most common procedure. This procedure results in an increase of about one octave immediately postoperatively and about half an octave after stabilization of the voice.

Cricoid Cartilage↗
PubMedDate not supplied

Surgical therapy in transsexual patients: a multi-disciplinary approach.

A transsexual patient has the constant and persistent conviction that he or she belongs to the opposite sex, thus creating a deeply seated gender identity conflict. With psychotherapy being unsuccessful, it has been proven that in carefully selected patients, gender reassignment or adjusting the body to the mind (both with hormones and surgery) is the best way to normalize their lives. Optimal treatment of these patients requires the multidisciplinary approach of a gender team with the input of several specialties. Such a team consists of a nucleus of physicians who sees the patient more frequently: the psychiatrist, the endocrinologist, the plastic surgeon, the gynecologist and the urologist and a more peripheral group that sees the patients more incidentally: the psychologist, the otorhinolaryngologist, the dermatologist, the speech therapist, the lawyer, the nurse and the social worker. Between 1987 and 1999, a total of 71 male-to-female (MTF) and 54 female-to-male transsexuals have undergone gender confirming surgery in our hospital. This article gives a review and an update on the different surgical procedures as well as on the outcome in our patient population. The results in this series of patients clearly demonstrate that a close cooperation of the different surgical specialties, within our multidisciplinary gender team, is the key to success in treating transsexual patients.

Female↗