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Biomedical subjects

S Karray

Publications and source records attributed to S Karray.

At least 37 records · Page 2Linked to original sources
PubMed1997

[A rare diaphyseal bone tumor: degenerative mucoid cyst].

The purpose of the study was to clarify the clinico pathological features of periosteal ganglion. The authors present a case of an unusual diaphyseal bony tumor in a 27 years old man. The diagnosis of diaphyseal periosteal ganglion cyst was made on roentgenographic appearance, presence of mucoid material and histologic evidence of a synovial type cellular lining. The patient was successfully treated with excision. The follow-up examination showed no recurrence one year after surgery. The radiological differential diagnosis were considered and possible pathogenes for a periosteal ganglion was discussed. Periosteal ganglia must be considered as a cause of cortical erosions. This lesion may radiologically mimic other periosteal lesions. Treatment with excision is successful in most cases.

Adult↗
PubMed1994

[Extra-renal retroperitoneal angiomyolipoma].

Angiomyolipoma is a benign kidney tumour. Its extrarenal, retroperitoneal site is exceptional. The authors report a case and emphasise the value of ultrasonography and computed tomography in the diagnosis of these tumours with a marked fatty component, without neglecting the contribution of arteriography which can be useful in the diagnosis of the origin of very large retroperitoneal tumours.

Angiomyolipoma↗
PubMed1993

[Tuberculosis of the trochanter. Apropos of 17 cases].

This paper presents a short study of 17 cases of tuberculosis of the greater trochanter seen during a period of 19 years at the National Orthopaedic Institute in Tunis. The onset of the infection is slow with patients presenting at a mean of 7 years after initial symptoms. The diagnosis is confirmed by biopsy and culture of the organism. Management is based on treatment with antituberculous drugs, although surgical excision of the lesion is sometimes required. Successful resolution of the symptoms is usually achieved unless the hip joint becomes involved. Our patients showed good results at a mean follow up of 5 1/2 years.

Adolescent↗
PubMed1993

Osteoid osteoma of the acetabulum.

Osteoid osteoma of the acetabulum can be expected to cause nonspecific symptoms of hip inflammation. In a sixteen year old girl, investigation by routine radiographs and a bone scan suggested a focus of inflammation with a nidus and sclerosis of the acetabulum and overgrowth of the head and neck of the femur. Removal of the lesion by an anterior approach with dislocation of the hip gave excellent results when seen after three years with a normal gait and normal hip motion.

Acetabulum↗
PubMed1993

Extensive vertebral hydatidosis. A study.

An exceptional case of vertebral hydatidosis with involvement of the cervical, dorsal, lumbar and sacral segments of the spine is presented. Vertebral hydatidosis is a rare form of hydatid disease. It is found in less than 2% of all cases in echinococcosis. The initial parasite localization is usually univertebral. Extensive primary lesions were related to massive infestation by tapeworm ova at multivertebral levels. At this stage, the disease presents as a malignant tumor resistant to all surgical procedures. The prognosis is poor because of severe neurological complications and inexorable spinal destruction. The hope remains that in the future an effective medical parasiticidal treatment will be available.

Adult↗
PubMed1992

[A case of bladder pheochromocytoma].

Phaeochromocytoma is an endocrine neuroectodermal tumour usually located in the adrenal gland, but occasionally arising in other organs. The authors report a case of a vesical phaeochromocytoma presenting with haematuria. Radiological and endoscopic investigations revealed a right laterovesical submucosal tumour. Partial cystectomy was performed. The normality of the postoperative endocrine survey suggested disappearance of the tumour and absence of any other sites.

Adult↗
PubMed1992

[Actinomyces pyogenes: conventional and Api system bacteriologic study of 103 strains isolated from ruminants].

One hundred and three strains of Actinomyces pyogenes isolated from ruminants were examined for morphological, cultural and biochemical properties by standard tests and by the Api 50 CH and Api Coryne methods. No biotype could be demonstrated, but a few atypical non- or practically non-proteolytic strains were detected which should be differentiated from Arcanobacterium haemolyticum. Criteria for laboratory identification of A pyogenes were established: Gram stain; culture on blood agar; deep agar and Loeffler's medium; catalase, nitrate reduction, acid formation from xylose; Hugh and Leifson test. The Api Coryne system correctly identified only 58 of 103 A pyogenes cultures, which implies that it should be re-evaluated before use in veterinary diagnosis laboratories.

Actinomyces↗
PubMed1990

IL-4 inhibits the expression of high affinity IL-2 receptors on monoclonal human B cells.

In the presence of anti-mu antibodies (anti-microAb), monoclonal B lymphocytes from patients suffering from B type chronic lymphocytic leukemia (B-CLL) can respond to IL-2. In contrast to the effect it exerts on normal B cells, IL-4 does not promote DNA synthesis by B-CLL lymphocytes. Rather this interleukin inhibits the response to IL-2 in all patients' cells that responded to this interleukin. We thus examined whether IL-4 would modulate the number and/or the affinity of IL-2 receptors. A 3-day activation of cells by anti-microAb induced a few hundred high affinity IL-2 receptors (HA-IL-2R) on B-CLL cell surface, as determined by Scatchard analysis. Treatment of cells with IL-4 caused a marked decrease in the number of HA-IL-2R without interfering with the binding ability of IL-2. In contrast with this profound suppressive effect, IL-4 did not down-regulate the expression of each chain, alpha and beta (p55 and p75, respectively), of the HA-IL-2R heterodimer. In fact, the expression of alpha and beta induced by anti-microAb was enhanced by IL-4. Altogether, IL-4 exerts a critical influence on the function and the configuration of HA-IL-2R without inhibiting the expression of two subunits, alpha and beta.

B-Lymphocytes↗
PubMed1990

B8.7 antigen expression on B-CLL cells and its relationship to the LMW-BCGF responsiveness.

In this work, we studied the expression of B8.7 antigen on B lymphocytes from patients suffering from B type chronic lymphocytic leukemia (B-CLL) as well as on non Hodgkin lymphoma cells (NHL). B8.7 is an activation marker, which has been reported to be associated with the capacity of activated B cells to respond to LMW-BCGF. B lymphocytes of 11 out of 22 patients tested were B8.7 positive. With the exception of one case, LMW-BCGF is able to induce DNA synthesis by these cells in the absence of costimulation by anti-mu antibodies (anti-mu Ab). The LMW-BCGF dependent proliferation of these malignant cells is inhibited by the anti-B8.7 monoclonal antibody (anti-B8.7 MoAb), in the same line as that of normal B cells. These results obtained with monoclonal B cells confirm that the B8.7 molecule is involved in the signalling pathway of the LMW-BCGF.

Aged↗
PubMed1990

Vertebral hydatidosis and paraplegia.

We report the management of two children and 11 adults with paraplegia secondary to vertebral hydatidosis. Destruction of pedicles, posterior vertebral elements and discs as well as the vertebral bodies was common and all six patients with thoracic disease had involvement of adjacent ribs. The 13 patients had a total of 42 major surgical procedures; two patients died from postoperative complications and four from complications of the disease and paraplegia. All eight patients initially treated by laminectomy or anterior decompression alone relapsed within two years and seven required further surgery. Circumferential decompression and grafting gave the best results, six of nine patients being in remission an average of three years and six months later. The prognosis for such patients is poor; remission is the aim, rather than cure. Anthelminthic drugs may improve the prognosis, but radical surgery is likely to remain the keystone of treatment in the foreseeable future.

Adolescent↗
PubMed1989

Interleukin (IL) 4 counteracts the helper effect of IL2 on antigen-activated human B cells.

We tested the effect of interleukin (IL) 4 on the specific IgM antibody response induced by trinitrophenylated-polyacrylamide beads (TNP-PAA) in cultures of human B cells. T cell help was provided by exogeneous IL2. IL4 profoundly suppressed the response to optimal concentrations (50 U/ml) of IL2, with a 50% inhibitory concentration of 6 U/ml. This was due neither to a shift in the kinetics nor to a switch to an IgG response. The production of anti-TNP antibody (as measured by an enzyme-linked immunosorbent assay in the culture supernatant) was inhibited to the same extent as the generation of plaque-forming cells. The effect of IL4 was completely abolished by a neutralizing antibody toward IL4. Kinetic studies showed that IL4 had to be present during the first 48 h of culture to fully inhibit the response. The sequential stimulation of B cells by antigen and by IL2 showed that IL4 does not negatively interfere with signaling through membrane Ig but counteracts the effect of IL2 on antigen-activated B cells.

Antibody Formation↗
PubMed1988

Interleukin 4 counteracts the interleukin 2-induced proliferation of monoclonal B cells.

B cells from patients suffering from B-type chronic lymphocytic leukemia (B-CLL) are susceptible to the effects of several interleukins. Using the cells from 12 different patients we show that IL-4 does not synergize with anti-mu antibody for the enhancement of DNA synthesis. Moreover IL-4 profoundly (90%) suppresses the response to IL-2 in the 10 patient responders to this interleukin. This suppression occurs whether IL-2 is used alone, in costimulation with anti-mu antibody, or in synergy with IFN-gamma. In no instance did IL-4 induce terminal differentiation. This negative effect of IL-4 can take place in monoclonal B-CLL cells where IL-4 enhances the expression of CD23. IL-4 does not interfere with the upregulation of CD25 by IL-2. Thus, IL-4 may display inhibitory effects on the proliferative response of selected B cell populations. The antagonism between IL-4 and IL-2 has important implications for the potential use of cytokines in the management of B-CLL patients.

Antibodies↗
PubMed1988

Positive effects of interferon-alpha on B cell-type chronic lymphocytic leukemia proliferative response.

We studied the effect of recombinant interferon-alpha (IFN-alpha) on the proliferative response of normal human B cells and of lymphocytes from 10 patients with B cell-type chronic lymphocytic leukemia. We show that IFN-alpha, which has no effect on B cell proliferation when used alone, can synergize with anti-mu antibody and can support DNA synthesis by anti-mu activated B cells. This was observed with normal B cells and in 4 of 10 patients with B cell-type chronic lymphocytic leukemia. These four patients were all responders to B cell growth factor (BCGF), whereas the responsiveness to IFN-alpha was not correlated with that of IL-2. The positive functional relationship between IFN-alpha and BCGF in these patients is emphasized by the synergistic effect of these two factors in two of these patients, and the lack of inhibition of BCGF response by even supraoptimal concentrations of IFN-alpha. Among the subgroup of patients unable to respond to IFN-alpha, a synergy between IFN-alpha and IL-2 could be observed.

Adult↗
PubMed1988

Induction of differentiation in human leukemic B cells by interleukin 2 alone: differential effect on the expression of mu and J chain genes.

The effects of interleukin 2 (IL2) on the proliferation and differentiation of B cells were analyzed separately using cells from two patients suffering from B-type chronic lymphocytic leukemia. The monoclonal B cells from these patients exhibited an opposite pattern of responsiveness upon in vitro culture with IL2 in the absence of other stimuli. In the first patient, IL2 alone was able to induce DNA synthesis and no Ig production. In the second patient, although no DNA synthesis was detected, B lymphocytes synthesized IgM upon stimulation with IL2 alone. Analysis of mRNA levels was performed on the cells of this latter patient after culture without or with IL2. In the presence of IL2 we observed a strong enhancement of C mu gene expression associated with an increase of the ratio between the secreted form and the membrane-bound form of mu mRNA. In contrast IL2 induced only a marginal enhancement of J chain mRNA. Thus, terminal B cell differentiation of selected monoclonal B cells can be obtained in the absence of DNA synthesis and IL2 alone can mediate this process. Moreover, IL2 can act at selective steps of the molecular events associated with IgM production. These results document the multiple effects of a given IL on the events leading to antibody production and strongly suggest that they can be conditioned by the maturation stage of a given responding cell.

B-Lymphocytes↗
PubMed1988

In vitro effects of B cell growth and maturation factor on B-CLL lymphocytes.

In the presence of anti-mu Ab, B-CLL lymphocytes are able to respond to cytokines such as IL2, BCGF and IFN-alpha. IL2 is most frequently an active factor. According to the B-CLL lymphocytes population, IL2 alone can induce growth or maturation of B cells. IFN-gamma and IL2 are inefficient on B-CLL lymphocyte proliferation, but they can profoundly modulate the response to IL2. IFN-gamma can synergize with IL2. In contrast IL4 profoundly and constantly inhibits the response to IL2.

B-Lymphocytes↗
PubMed1987

Synergistic effect of recombinant IL 2 and interferon-gamma on the proliferation of human monoclonal lymphocytes.

We studied the effect of interferon-gamma (IFN-gamma) on the proliferation of lymphocytes from 10 B-type chronic lymphocytic leukemia (B-CLL) patients. In no instance did IFN-gamma induce a proliferative response whether used alone or in combination with anti-mu antibody (Ab). This was observed regardless of the responsiveness of a given patient's cells to interleukin 2 (IL 2) and to B cell growth factor (BCGF). In contrast IFN-gamma strongly and reproducibly synergized with IL 2 (but not with BCGF) to support B-CLL proliferation in five of the 10 patients. The effect of IFN-gamma was dose related and could be inhibited by an anti-IFN-gamma monoclonal Ab. A monoclonal Ab toward the IL 2 receptor molecule was also inhibitory. Preincubation with IFN-gamma potentiated the responsiveness of B-CLL to IL 2 in secondary cultures, showing that IFN-gamma exerts its effect before that of IL 2.

B-Lymphocytes↗
PubMed1987

A T chronic lymphocytic leukemia with large granular lymphocytes. Phenotype and functions of leukemic cells under in vitro treatment by differentiation inducers.

We reported the morphologic, phenotypic and functional characteristics of leukemic cells with natural killer (NK) properties in a case of T chronic lymphocytic leukemia with large granular lymphocytes. These cells were cytologically and cytochemically characterized as phosphatase acid positive large granular lymphocytes (LGL), and presented parallel tubular arrays at the ultra structural level. They displayed a CD2, CD3, CD8, CD11, Leu 7, and Leu 11 positive phenotype while they lacked B cell markers including surface immunoglobulins. In addition, they expressed human leukocyte antigens (HLA) Class I, but no Class II antigens. These phenotypic studies were also performed after cells were cultured in vitro with 12-0-tetradecanoyl phorbol 13-acetate, gamma interferon, 5-azacytidine, sodium butyrate, phytohemagglutinin, and interleukin 2 (IL2). The cell surface markers underwent several significant changes. Among them we noted a higher percentage of labeled cells with anti-CD6 and CD7 monoclonal antibodies (moAbs), and a positivity with an anti-CD19 (B4) moAb. The leukemic LGL spontaneously developed a NK activity on K 562 tumor cells, which was not affected under the various T and B cells growth factors because they became more sensitive to IL2; but they were also stimulated by a 50-kilodalton (KD) B cell growth factor (BCGF) factor devoid of any T cell proliferation activity. Together these results gave a better characterization of azurophilic granules containing T chronic lymphocytic leukemia, and enabled the documentation of the differentiation of LGL with NK activity.

Adult↗