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T Simonart

Publications and source records attributed to T Simonart.

At least 19 recordsLinked to original sources
PubMed2001

Immunologic and virologic response after tetanus toxoid booster among HIV-1- and HIV-2-infected Senegalese individuals.

Twelve HIV-1-infected, nine HIV-2-infected patients and eight HIV-negative subjects were given a 40IU booster dose of tetanus toxoid (TT). Blood was collected on days 0, 7 and 30 after immunization. Changes in HIV-1 or HIV-2 RNA load were evaluated by nested PCR. TT-IgG antibody levels were quantified by ELISA. CD4 cell counts as well as activation, memory and maturation markers of T lymphocyte subsets were determined by flow cytometry. The induction of apoptosis was investigated using 7-aminoactinomycin D (AAD) and propidium iodide (PI) staining. Proliferative responses to TT and pokeweed mitogen (PWM) were determined by the level of [(3)H] thymidine incorporation. Seven and 30 days after immunization, there was no detectable increase in HIV-1 or HIV-2 plasma load. There were also no changes in CD4 cell counts, CD69, HLA-DR and memory CD45RO or naive CD45RA antigens. Immunization did not increase the spontaneous apoptosis of peripheral blood mononuclear cells (PBMCs), CD4+ and CD8+ T cells subsets neither in controls nor in HIV-infected patients. Similarly, apoptosis induced in vitro by PWM or by the specific TT recall antigen did not vary during the study period. The proliferative response to PWM and to the TT recall antigen was decreased both in HIV-1- and HIV-2-infected patients compared to HIV-negative controls. Immunization significantly increased the TT-IgG levels in healthy controls and in HIV-infected patients. However, the anti-TT-IgG response, as measured by the fold-increase index between days 0 and 30, was significantly higher in healthy controls than in HIV-1- (P=0.036) and HIV-2-infected patients (P=0.003). In conclusion, we found no deleterious immunologic or virologic effect was detected in healthy HIV-1- and HIV-2-infected individuals after antigenic challenge with a TT booster. However, the response to TT vaccination was lower in HIV-1- and in HIV-2-infected individuals than in healthy HIV-negative controls.

Adult↗
PubMed2001

Cultured Kaposi's sarcoma tumor cells exhibit a chemokine receptor repertoire that does not allow infection by HIV-1.

BACKGROUND: HIV-1 is known to play a critical role in the pathogenesis of AIDS-associated Kaposi's sarcoma (KS). However, it remains controversial whether KS cells are target cells for HIV infection. The aim of this study was to investigate the expression of chemokine receptors in KS cell cultures and to determine whether these cells can be infected by HIV-1. MATERIAL AND METHODS: KS-derived cells and KS-Y1 cells were investigated using RT-PCR for the expression of CD4, CCR3, CCR5, CCR8 and CXCR4 mRNA. HIV infectivity of these cells was determined by p24 antigen and HIV-1 RNA production, as well as by HIV-1 DNA integration. RESULTS AND DISCUSSION: With the exception of CCR8 which is expressed by KS-derived spindle cell cultures but not by KS-Y1 cells, unstimulated KS cells express no significant levels of CD4, CCR3, CCR5 or CXCR4 mRNA. HIV infectivity assays showed that KS cells were unpermissive to HTLVIIIB and JRFL strains. Although the expression of CXCR4 mRNA could be upregulated by interleukin-1beta, stimulation of KS cells by this cytokine did not allow infection by HIV-1. CONCLUSIONS: This shows that KS cells exhibit a chemokine receptor repertoire that does not allow infection by HIV-1. Other cell types making up KS lesions, such as inflammatory cells, are likely to represent the source of HIV-1 products cooperating to promote KS development and progression.

Actins↗
PubMed2001

Impact of surgical resection of rectovaginal pouch of douglas endometriotic nodules on pelvic pain and some elements of patients' sex life.

STUDY OBJECTIVE: To assess the impact of laparoscopic resection of endometriotic nodules in the rectovaginal pouch of Douglas on women's pain symptoms, analgesic intake, work absenteeism, work difficulties, and some elements of sex life. DESIGN: Observational study (Canadian Task Force classification II-2). SETTING: Gynecology department at a university hospital. PATIENTS: Twenty-six women with rectovaginal pouch of Douglas endometriotic nodules and no evidence of other potential cause of pain at physical examination, laparoscopy, and transvaginal ultrasonography. INTERVENTION: Laparoscopic resection of endometriotic nodules with the CO2 laser until no residual induration was felt in surrounding tissues. MEASUREMENTS AND MAIN RESULTS: Significant statistical differences were found between preoperative and postoperative pain scores, percentages of women absent from work, percentages taking analgesics or nonsteroidal antiinflammatory drugs, and percentages having work difficulties due to pain. A significant difference also was found in frequencies of sexual desire and coitus. CONCLUSION: Endometriotic nodules in the rectovaginal pouch of Douglas may be responsible for major pelvic pain and also for sexual dysfunction (lack of sexual desire, dyspareunia). Laparoscopic resection of the nodules significantly improves these conditions. (J Am Assoc Gynecol Laparosc 8(1):55-60, 2001)

Adult↗
PubMed2001

Kaposi's sarcoma, oncogenic viruses, and iron.

INTRODUCTION: Iron is required for many cellular processes, but it is also toxic in excess quantities. Therefore, iron homeostasis and utilization must be strictly maintained, and defects in iron absorption or transport result in iron depletion or accumulation. Most research has been directed to enteral and placental transfer of iron, but little is known about iron entry through the skin. We present evidence that exposure to wet clay soils in Africa is an important risk factor for Kaposi's sarcoma (KS) and speculate that iron may be responsible for soil toxicity contributing to the pathogenesis of KS. STUDY DESIGN: Evidence gathered from case control studies and related investigations in Uganda between 1995 and 1998 are summarized. RESULTS: A large case control study of KS in HIV-infected adults disclosed affluence and mobility that suggest enhanced sexual exposure to human herpesvirus-8, the putative aetiologic agent of KS. Another study in endemic KS (HIV-negative) also showed affluence and mobility as risk factors. In addition, barefoot exposure to wet soil was an important risk factor for men with endemic KS. Other studies point to diminish delayed hypersensitivity in the lower limbs of KS patients. Geographic similarities of KS to podoconiosis (non-filarial elephantiasis) in Africa implicate soil absorbtion through the skin in the pathogenesis of KS and podoconiosis. CONCLUSION: The hypothesis of soil exposure as a risk for endemic KS has been strengthened by recent investigation. Particulate soil exposure may cause localized microtrauma and inflammation, predisposing to KS on the extremities in HHV-8 infected men. A role for iron toxicity is yet to be determined.

Case-Control Studies↗
PubMed2001

Early- and late-stage Kaposi's sarcoma-derived cells but not activated endothelial cells can invade de-epidermized dermis.

Whether Kaposi's sarcoma is a true neoplasm or a reactive endothelial cell outgrowth triggered by inflammatory cytokines remains unclear. In this study, we investigated the differential invasive properties of activated endothelial cells and Kaposi's sarcoma cells in a model of de-epidermized dermis, supplying the cells with matrix barriers similar to those found in vivo. Cells derived from early "patch-stage" and from late "nodular-stage" Kaposi's sarcoma lesions exhibited similar invasive properties, which indicates that cells with an invasive potential are present in the early stages of tumor development. Slow accumulation of the cells into the extracellular matrix, together with a low proliferation index and with expression of anti-apoptotic proteins, suggest that the progression of Kaposi's sarcoma may be related to escape from cell death rather than to increased proliferation. The Kaposi's sarcoma-Y1 cell line, which is tumorigenic in nude mice, also exhibited invasive properties. By contrast to the Kaposi's sarcoma-derived spindle cells, however, which were scattered between the collagen bundles, the Kaposi's sarcoma-Y1 cell population had a higher proliferation index and displayed a multilayer arrangement. Inflammatory cytokines and Kaposi's sarcoma cell supernatant could activate and stimulate the growth of human dermal microvascular endothelial cell, but could not induce their invasion in this model, showing that activated endothelial cells do not fit all the requirements to traverse the various barriers found in the dermal extracellular matrix. These results confer to Kaposi's sarcoma cells a tumor phenotype and suggest that the in vivo dominant endothelial cell population represents a reactive hyperplasia rather than the true tumor process.

Cell Division↗
PubMed2001

Iron induces Bcl-2 expression in human dermal microvascular endothelial cells.

Iron is suspected to be involved in the induction and/or progression of various human tumors. The present study was designed to investigate the effects of iron on endothelial cells, keeping in mind that the homeostasis of microvessels plays a critical role in neo-angiogenesis. Applying a model of human dermal microvascular endothelial cell terminal differentiation and death induced by serum deprivation, we found that iron salts (iron chloride and ferric nitrilotriacetate) provided a survival advantage to endothelial cells. Using immunohistochemistry and Western Blot analysis, we found that the extended cellular life span induced by iron was paralleled by an increase of Bcl-2 protein expression. Taken together, these observations suggest that iron may give a survival advantage to endothelial cells and represent a novel mechanism through which iron may contribute to tumorigenesis.

Cell Line↗
PubMed2001

Value of standard laboratory tests for the early recognition of group A beta-hemolytic streptococcal necrotizing fasciitis.

The laboratory data for 17 patients with group A beta-hemolytic streptococcal necrotizing fasciitis (GAS NF) were compared with data for 145 patients hospitalized for cellulitis during the same period. Admission values of C-reactive protein and creatine kinase were higher for patients in the group with GAS NF than for patients in the group with cellulitis (P<.001), suggesting that standard laboratory tests may be useful for the early differential diagnosis of GAS NF and cellulitis.

Adolescent↗
PubMed2001

Treatment of idiopathic palmar hyperhidrosis with botulinum toxin. Report of 23 cases and review of the literature.

BACKGROUND: Botulinum toxin represents a novel therapeutic option for idiopathic palmar hyperhidrosis. However, so far there is no consensus on the way to administer botulinum toxin in this indication. Moreover, its use is limited by severe pain during the injections, especially with subepidermal injections close to 'free nerve endings'. OBJECTIVES: To analyze the effectiveness and tolerability of intracutaneous injections of botulinum toxin after nerve blocks and to review the techniques of injections and the results reported by other groups. METHODS: Twenty-three adult patients with refractory palmar hyperhidrosis were treated with intracutaneous injections of botulinum toxin after ulnar and median nerve blocks. Patients were followed up on a monthly basis. RESULTS: In all patients botulinum toxin abolished sweating in the injected areas within 1 week. Anhidrosis lasted for 4-13 months. The intensity of pain was rated as absent (n = 13), mild (n = 8) or moderate (n = 2). Other side effects included hematoma (n = 2) and pain consecutive to nerve block (n = 1). DISCUSSION: Intracutaneous injections of botulinum toxin after median and ulnar nerve block represent an effective and mildly painful technique to treat palmar hyperhidrosis and may be as safe as subepidermal injections.

Adolescent↗
PubMed2000

Kaposi's sarcoma.

Explore the source record for details and available documents.

Chorionic Gonadotropin↗
PubMed2000

Multinucleate cell angiohistiocytoma: report of two cases with no evidence of human herpesvirus-8 infection.

Multinucleate cell angiohistiocytoma (MCA) is a vascular tumor of unknown pathogenesis. Possible misinterpretation of this disorder with Kaposi's sarcoma (KS), a human herpesvirus-8 (HHV-8)-associated tumor, prompted us to look for this virus in two women with MCA. None of the multiple skin specimens obtained from both our patients produced amplified HHV-8 DNA. Using a cell culture methodology similar to that used for KS, we established cell cultures from MCA lesions. While KS spindle cells are known to exhibit in vitro invasive properties and can be grown up to more than 20 passages, the MCA-derived cells were short-lived and were not able to traverse basement membranes. Taken together, our data support the hypothesis that MCA is not a neoplasm but a benign vascular proliferation which is clearly distinguishable from KS.

Aged↗
PubMed2000

Langerhans' cell histiocytosis arising at the site of basal cell carcinoma excision.

Langerhans' cell histiocytosis (LCH) may be associated with a wide range of neoplastic disorders. However, the combination of a LCH and a basal cell carcinoma (BCC) of the skin still represents a highly unusual condition. In this publication, we report the case of a 48-year-old woman who developed a localized LCH involving the area of a previously excised BCC. Although the exact pathogenesis of this peculiar association remains yet to be elucidated, the hypothesis of an exaggerated Langerhans' cell reaction in response to the underlying BCC appears to be attractive.

Basal Cell Carcinoma↗