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K Mokhtari

Publications and source records attributed to K Mokhtari.

41 records · Page 3Linked to original sources
PubMed1997

AIDS-related primary brain lymphomas: histopathologic and immunohistochemical study of 51 cases. The French Study Group for HIV-Associated Tumors.

Fifty-one cases of acquired immunodeficiency syndrome (AIDS)-related primary brain lymphomas (AR-PBL) were investigated for clinical characteristics; human immunodeficiency virus (HIV)-associated disorders; histopathologic features; immunophenotype; Epstein-Barr virus (EBV) infection; and, when frozen tissue was available, oncogene rearrangements. AR-PBL occurred late in the course of AIDS and were usually associated with other systemic or cerebral disorders and with a low level of CD4 lymphocytes. All cases were high grade lymphomas according to the Working Formulation or updated Kiel classification, and often displayed a multifocal pattern. Thirty cases were classified as immunoblastic with plasmacytic differentiation, 18 cases were large cell lymphomas with an immunoblastic component or centroblastic polymorphic lymphomas, and 2 were small noncleaved non-Burkitt lymphomas (Working Formulation). This latter category is classified as Burkitt's-like lymphoma in the REAL nomenclature. One case could not be classified because of necrosis. AR-PBL showed a high level expression of activation and adhesion molecules. The presence of EBV was detected in most cases, and, when PCR was used, this was a constant finding. bcl-2 oncoprotein and latent membrane protein-1 (LMP-1) were strongly expressed. None of the tested cases expressed p53, or were rearranged for bcl-2 or c-myc oncogenes. This study confirms the immunophenotypic specificity of AR-PBL, which may reflect the special immune status of the brain.

Adult↗
PubMed1997

Human immunodeficiency virus type 1 DNA and RNA load in brains of demented and nondemented patients with acquired immunodeficiency syndrome.

The relationship between dementia and human immunodeficiency virus type 1 (HIV-1) cerebral load is not clearly understood. We used immunohistochemistry and competitive polymerase chain reaction to evaluate the density ofgp 41 immunostained cells and the amount of HIV-1 DNA and RNA in the midfrontal gyrus of 21 HIV-1 infected patients, nine of whom were demented. The amounts of HIV-1 DNA and RNA, and the density of gp 41-positive cells were significantly linked. In this small series of cases, (1) although as a mean, there was a larger viral load in demented patients than in nondemented, this did not reach the significance level (2) discrepancies appeared in the population under study, some demented patients having low viral loads.

AIDS Dementia Complex↗
PubMed1996

Inconstant apolipoprotein E (ApoE)-like immunoreactivity in amyloid beta protein deposits: relationship with APOE genotype in aging brain and Alzheimer's disease.

The aim of this study was to analyze the relationship between apolipoprotein E (ApoE) and amyloid beta-protein (A beta) deposits in 29 brains from a series of elderly women, whose intellectual status had been prospectively assessed by the Blessed test score (BTS). In three cases the APOE genotype was epsilon 3/4, in one epsilon 2/2, in 25 epsilon 3/3. ApoE-like immunoreactive lesions resembling a classic senile plaque (ApoE-SP) or a diffuse deposit (ApoE-DD) were quantitatively assessed in the first temporal gyrus (Brodmann's area 22). The density of ApoE-positive deposits (ApoE-SP+ApoE-DD) was correlated with BTS (negative correlation R2 = 0.36, P = 0.0006). The correlation of the density of ApoE-DD with BTS (R2 = 0.26, P = 0.0051) was weaker than that of ApoE-SP (R2 = 0.50, P < 0.0001). The density of ApoE deposits was correlated with that of A beta-immunoreactive lesions (positive correlation R2 = 0.57, P < 0.0001). ApoE immunohistochemistry labeled fewer deposits than A beta immunohistochemistry but showed as many senile plaques (ApoE-SP) as tau immunohistochemistry and the Gallyas and Bodian techniques. Two of the three cases with the epsilon 3/4 allele had Alzheimer's disease (AD) with numerous ApoE-immunoreactive senile plaques. In contrast, the brain of the third epsilon 3/4 case, whose intellectual status was normal, contained numerous A beta deposits but lacked ApoE-like immunoreactivity. The presence of ApoE may, thus, not be a prerequisite for A beta deposition, even in cases with the epsilon 3/4 allele. The density of ApoE-SP peaked in layer III, whereas that of ApoE-DD was maximal in deeper cortical layers. This contrast in the laminar distribution indicates that only some ApoE-DD may evolve into ApoE-SP. ApoE deposition was linked to the intellectual decline and was constant in the most severely demented patients, in whom numerous ApoE-positive (and A beta-positive) neuritic plaques were surrounded by dystrophic neurites. ApoE may accumulate in neuritic senile plaques during the progression of AD.

Aged↗
PubMed1995

[Neuropathology of non conventional infectious agents or prions].

The neuropathological diagnosis of infections by non conventional agents relies on four lesions: astrocytic gliosis (cell hypertrophy and proliferation) usually contrasting with absent mononuclear cell infiltrates (lymphocytes, monocytes-macrophages, and/or microglia) revealed by conventional techniques, and neuronal loss in the most affected areas are little specific findings. Amyloid plaques that are inconstantly found, and spongiosis of gray matter, a characteristic and very frequent finding, are most specific. PrP immunohistochemistry brings additional data. The main diagnostic difficulties are emphasized, and guidelines for Pathological studies are recalled.

Animals↗