PubMed Health⌕ Search

Biomedical subjects

M Abdelmoula

Publications and source records attributed to M Abdelmoula.

15 recordsLinked to original sources

[Mandibular Langerhans cell histiocytosis].

INTRODUCTION: Langerhan's cell histiocytosis is defined as an abnormal proliferation of Langerhans cells in various organs and tissues (bone, skin, lymph nodes...). Among facial locations, mandibular involvement is the most frequent and occurs in young people less than 20 years. The aim of this report is to review the characteristic features of this disease, the current means of diagnosis and treatment through two case reports. CASES: Two male patients aged 10 and 55 years respectively presented with single mandibular location of Langerhans cell histiocytosis. The diagnosis was confirmed by histological examination of the biopsy specimen. The first patient underwent surgical resection of the tumor. No recurrence was observed. In the second patient, the postoperative course was marked by the appearance of an inflammatory phenomenon in the adjacent skin and mucosa, successfully treated by intralesional corticosteroid therapy. DISCUSSION: Langerhan's cell histiocytosis is a rare disease. The mandibular location has variable clinical expressions which can vary from dental mobility to tumor development in the gingiva. The radiological appearance is also variable; histological proof is required for diagnosis. Treatment depends on the number and locations of the lesions. In case of a single location, the treatment options may vary from a "wait and see" attitude to a non aggressive surgery, with a possible local corticosteroid therapy or radiothe-rapy. For multiples locations, chemotherapy is indicated.

Child↗

[Facial mucormycosis: observations from three cases].

The mucormycosis is a rare opportunistic invasive infection caused by fungi of the order Mucorales and characterized by vascular invasion and tissue necrosis. It affects generally the subjects with altered natural resistances, particularly the diabetics patients. The cerebro-rhino-orbital region is the most common site. The clinical signs depend on the intra-tissular and intra-vascular evolution of the fungi. The diagnosis of this disease is asserted by the mycological and anatomo-pathological exams. The treatment is based on the antifungic and the surgical excision of necrotic tissues. We report three observations: one man (42 years) and two women (59 and 60 years). Diabetes was found in two cases. The diagnosis was in every case anatomo-pathologic. Our objective was to study the epidemiological and clinico-pathologic aspects of this serious affection and to discuss its prognosis.

Adult↗

[Rhinocerebral mucormycosis: apropos of 4 new Tunisian cases].

Mucormycosis is a rare opportunistic infection but a fulminant disease. We report the 4 first cases of rhinocerebral mucormycosis diagnosed in Sfax region (Tunisia). They occurred in insulin dependent diabetes and developed varying clinical manifestations from facial cellulites to ocular and cerebral extension. The diagnosis of mucormycosis was not initially evoked, but confirmed tardively by anatomopathologic and mycologic examinations. The evolution was favourable in 2 cases by administration of amphotericine B associated with extensive surgical debridement and correction of the diabetes. Two patients had a fatal outcome. This infection has a severe prognosis and necessitates early diagnosis.

Adult↗

[Exophthalmos and blindness disclosing an ethmoidal-maxillary malignant non-Hodgkin's T-cell lymphoma. Apropos of a case].

BACKGROUND: We report a case of non-Hodgkin's malignant lymphoma of the cervicofacial region revealed by unilateral exophthalmos and blindness, an unusual mode of expression. CASE REPORT: A 40-year-old man with a 4-month history of diabetes mellitus had suffered from exophthalmos and blindness of the right eye for 20 years. Physical examination showed a homolateral hemifacial tumefaction and ophthalmoplegia. The right ocular fundus showed papillar edema and non-proliferative diabetic retinopathy. The left eye was normal. The otolaryngology explorations revealed a voluminous tumor in the anterior nasal cavity and in the cavum. Two biopsies were performed. Histology reported non-Hodgkin's T-cell lymphoma. Orbitocerebral and cervicofacial computed tomography visualized the aggressive ethmoidomaxillary extension with intraorbital and intracranial involvement. Chemotherapy (CHOP) combined with radiotherapy led to tumor regression and involution of the exophthalmos. Diagnostic difficulties, management and prognosis are discussed.

Adult↗

[Primary teratoma of the orbit. Apropos of a case].

Primary teratomas rarely occur in the orbit leading to major exophthalmia in the neonate. We report a case in a female infant who presented globular right exophthalmia extending beyond the orbit caused by a teratoma of the orbit. There was right ophthalmoplegia. Computed tomography showed enlargement of the orbit without modification of the bony structure despite the tumor volume. Tumoral enucleation was performed via the transconjunctive route. Histology reported benign mature multi-tissue teratoma. The postoperative course was uneventful. The CT-scan at 6 months evidence the absence of recurrence, outcome which has been confirmed after a 5-years follow-up.

Exophthalmos↗

[A simple procedure for the passive suspension of the paralyzed labial commissure].

Different techniques can be used to repair paralytic labial commissurae. Ideally, microsurgical procedures or dynamic suspension methods can correct kinetic paralysis but in certain patients (elderly subjects, poor general health, precarious postsurgical rehabilitation) such procedures may represent an excessively aggressive procedure. We therefore used static suspension of the paralytic labial commissurae based on desepidermization of a nasogeneal flap. This simple technique is easy to perform and is our method of choice for static suspension because the flap pulls the paralysed commissurae upward and doubles the tissue cover, helping overcome buccinator incompetence.

Adult↗

IgG3 is the major source of cryoglobulins in mice.

A total of 20 of 23 IgG3 mAb derived from unmanipulated autoimmune MRL/MpJ-lpr/lpr mice was shown to generate cryoglobulins which were composed exclusively of IgG3. Although three IgG3 mAb failed to develop cryoglobulins, they were able to bind nonspecifically to any IgG3 molecules as efficiently as cryoprecipitable IgG did. The direct role of the gamma 3 constant region for the generation of cryoglobulins was demonstrated by the following findings: 1) the cryoglobulin activity was independent of the specificity of the IgG3 mAb, 2) no mAb other than those of the IgG3 subclass, including IgM rheumatoid factors (RF), generated cryoglobulins, and 3) the cryoglobulin activity was gained after the Ig class switch of mAb from IgM to IgG3. Analysis of Ig components in three different sources of cryoglobulins, either induced by the injection of bacterial LPS or by the infection with Plasmodium yoelii in BALB/c mice or developed spontaneously in MRL/MpJ-lpr/lpr mice, revealed the selective concentration of IgG3 in these cryoglobulins; greater than 99%, 73% and 58% of IgG recoverable from these three cryoglobulins, respectively, were IgG3. This further attests to the major role of IgG3 in the generation of cryoglobulins in mice. In addition, the enhanced formation and even induction of IgG3 cryoglobulins in the presence of IgM anti-IgG3 RF mAb, and the enrichment of IgM RF in LPS- or malaria-induced cryoglobulins indicated that IgM RF can be involved in the generation of cryoglobulins by interacting with noncryoprecipitable IgG3 as well as cryoprecipitable IgG3.

Animals↗

Igh-C allotype-linked control of anti-DNA production and clonotype expression in mice infected with Plasmodium yoelii.

The infection of nonlethal strain of Plasmodium yoelii induces the formation of IgG anti-DNA antibodies as a result of polyclonal B cell activation. By using various nonautoimmune strains of mice including H-2 or Igh congenic or recombinant mice, the levels and clonotypes of anti-DNA antibodies elicited by the malaria infection were analyzed in relation to the expression of the MHC or Igh gene. Our results showed there were little, if any, differences in serum anti-DNA levels and their clonotypes among B10 and B6 H-2 congenic mice. In contrast, malaria-induced IgG anti-DNA responses markedly differed quantitatively and clonotypically between murine strains bearing the Ighb allotype and those bearing the Igha, Ighj, Ighd, or Ighn allotype. The latter group of mice produced approximately 5 to 10 times more IgG anti-DNA antibodies than the former group of mice. Clonotypically, mice bearing the Ighb allotype developed high alkaline anti-DNA antibodies of pH 8.0 to 8.5, whereas non-Ighb mice failed to express such alkaline anti-DNA spectrotypes, and exhibited more neutral spectrotypes (pH 7.0 to 8.0). Studies on the Igh recombinant mice indicated that the observed quantitative and clonotypical differences in IgG anti-DNA production was not associated with the variable region, but with the constant region of the Igh gene complex. Our results have suggested that IgG anti-DNA responses occurring as a result of polyclonal B cell activation during the course of malaria infection markedly differs quantitatively and clonotypically among murine strains and appear to be controlled at least in part by the Igh-C gene or gene(s) closely linked to it.

Animals↗

Cryoglobulinemia induced by monoclonal immunoglobulin G rheumatoid factors derived from autoimmune MRL/MpJ-lpr/lpr mice.

A MRL strain bearing the autosomal recessive mutant gene, lpr (lymphoproliferation), spontaneously develops, in addition to a lupus-like syndrome, unique serological and pathological manifestations. Production of high titers of IgG rheumatoid factors (RF) may be related to the formation of extremely large amounts of cryoglobulins and the development of tissue lesions such as necrotizing polyarteritis, arthritis, and glomerulonephritis. To analyze more directly the relationship of IgG RF to the development of cryoglobulins and tissue injuries, we have established four monoclonal IgG RF secreting hybridomas from unimmunized MRL-lpr/lpr mice and determined their pathogenic effects in normal strains of mice. All the monoclonal IgG RF obtained in this study were of the IgG3 subclass and generated cryoglobulins. However, the fact that not only IgG3 Rf monoclonals but also four of five non-RF IgG3 monoclonals were able to form cryoglobulins, which were composed exclusively of each IgG3 monoclonal, indicates that the IgG3 molecule has a unique physicochemical property to self-associate via nonimmunological interaction and the ability to form cryoglobulins. When the in vivo pathogenic activities of these IgG3 RF and non-RF monoclonals were examined, three of IgG3 RF monoclonals with the specificity to IgG2a were able to induce extensive pathologic manifestations including peripheral vasculitis and glomerulonephritis characteristic of patients with cryoglobulinemia. Our results indicate that the IgG3 itself, independently of its specificity, could be a potential source of cryoglobulins and IgG3 RF, combined with its activity of cryoglobulin formation, may play a significant role in the development of glomerulonephritis and cutaneous vascular lesions of ears and foot pads observed frequently in aged MRL-lpr/lpr mice.

Animals↗

IgG rheumatoid factors and cryoglobulins in mice bearing the mutant gene lpr (lymphoproliferation).

The autosomal recessive mutant gene, lpr (lymphoproliferation), produces a massive proliferation of T cells in autoimmune MRL mice. Since the MRL strain bearing the lpr mutation is the only strain that spontaneously develops high titers of rheumatoid factors (RF), we have investigated whether non-autoimmune mice (C57BL/6, C3H/HeJ and AKR) bearing the lpr gene could produce RF. Serum levels of RF activity were assessed by a new radioimmunoassay, in which serum samples pretreated with acetate buffer were incubated with 125I-mouse IgG and precipitated with 7% polyethylene glycol. The majority of serum from 4- to 6-month-old non-autoimmune strains of mice bearing the lpr gene exhibited significant RF activity, as did MRL-lpr/lpr mice. Sucrose density-gradient analysis has revealed that all the IgG RF activity was present in a form of immune complexes, sedimenting in the intermediate position (7-19S) and fully dissociable into 7S IgG under an acid condition. This indicates that the production of IgG RF does not require a particular background genome of the MRL strain. In addition, mice bearing the lpr mutation developed extremely large amounts of cryoglobulins, which paralleled the production of RF. Analysis of components of their cryoglobulins revealed a marked enrichment of IgG3 subclass as compared to other IgG subclasses and IgM. These results suggest that IgG3-containing immune complexes represent the major source of cryoglobulins occurring in mice bearing the lpr gene.

Animals↗

Characterization of iron and manganese precipitates from an in situ ground water treatment plant.

Aquifer samples from the precipitation zone of an in situ iron and manganese removal plant that was operated for 10 years were analyzed for iron and manganese minerals. Measurements were performed by various chemical extraction techniques (5 M HCI, 0.008 M Ti(III)-EDTA, 0.114 M ascorbic acid), X-ray diffraction and Mössbauer spectroscopy. Chemical extractions showed that iron was precipitated as ferric oxides, whereas manganese was not oxidized but deposited as Mn(II) probably within carbonates. The ferric oxides in particular accumulate preferentially in the smaller grain- size fractions. This tendency was observed to a lesser extent for manganese. X-ray diffraction and Mössbauer spectroscopy showed that the ferric oxides were mainly crystalline (goethite, 50% to 100% of the iron). Ferrihydrite was found as well, but only as a minor fraction (< or = 12%). Pure manganese minerals were not found by X-ray diffraction. The precipitated amounts of iron (5 to 27 micromol/g Fe as ferric oxide) and manganese (1 to 4 micromol/g Mn) during 10 years operation of the treatment plant agree with values that were estimated from operational parameters (9 to 31 micromol/g Fe and 3 to 6 micromol/g Mn). Considering the small amounts of precipitated iron and manganese, no long-term risks of clogging of the aquifer are expected.

Iron↗