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P Portegies

Publications and source records attributed to P Portegies.

At least 19 recordsLinked to original sources
PubMed1999

Overexpression of nerve growth factor and basic fibroblast growth factor in AIDS dementia complex.

Although neurotrophic factors are currently considered as treatment for neurodegenerative diseases, little is still known about their presence in the central nervous system under pathological conditions. We investigated the expression of the neurotrophic molecules NGF, bFGF, BDNF and IGF-1 in brain tissue of patients suffering from AIDS dementia complex. In contrast to IGF-1 and BDNF, NGF and bFGF mRNA levels were significantly elevated. Strong NGF immunoreactivity was found in perivascular areas and was colocalized with infiltrating macrophages, whereas intense bFGF staining was found in cells with characteristic astrocytic morphology. These data suggest that the induction of NGF and bFGF alone appears to be insufficient as a compensatory mechanism to prevent ADC.

AIDS Dementia Complex↗
PubMed1999

Increased peroxynitrite activity in AIDS dementia complex: implications for the neuropathogenesis of HIV-1 infection.

Oxidative stress is suggested to be involved in several neurodegenerative diseases. One mechanism of oxidative damage is mediated by peroxynitrite, a neurotoxic reaction product of superoxide anion and nitric oxide. Expression of two cytokines and two key enzymes that are indicative of the presence of reactive oxygen intermediates and peroxynitrite was investigated in brain tissue of AIDS patients with and without AIDS dementia complex and HIV-seronegative controls. RNA expression of IL-1beta, IL-10, inducible nitric oxide synthase, and superoxide dismutase (SOD) was found to be significantly higher in demented compared with nondemented patients. Immunohistochemical analysis showed that SOD was expressed in CD68-positive microglial cells while inducible nitric oxide synthase was detected in glial fibrillary acidic protein (GFAP)-positive astrocytes and in equal amounts in microglial cells. Approximately 70% of the HIV p24-Ag-positive macrophages did express SOD, suggesting a direct HIV-induced intracellular event. HIV-1 infection of macrophages resulted in both increased superoxide anion production and elevated SOD mRNA levels, compared with uninfected macrophages. Finally, we show that nitrotyrosine, the footprint of peroxynitrite, was found more intense and frequent in brain sections of demented patients compared with nondemented patients. These results indicate that, as a result of simultaneous production of superoxide anion and nitric oxide, peroxynitrite may contribute to the neuropathogenesis of HIV-1 infection.

AIDS Dementia Complex↗
PubMed1999

Nitric oxide synthase expression and apoptotic cell death in brains of AIDS and AIDS dementia patients.

OBJECTIVES: To determine the occurrence and cellular localization of inducible nitric oxide synthase (iNOS), NOS activity and its association with cell death in brains of AIDS and AIDS dementia complex (ADC) patients. DESIGN AND METHODS: Post-mortem cerebral cortex tissue of eight AIDS patients, eight ADC patients and eight control subjects was processed for iNOS immunocytochemistry, NADPH-diaphorase activity staining as an index of NOS activity, and in situ end-labelling to detect cell death. RESULTS: iNOS-positive cells were present in the white matter of 14 out of 16 AIDS and ADC patients, whereas two out of eight control subjects showed iNOS-positive cells. iNOS immunoreactivity was exclusively localized in activated macrophages and microglial cells that both showed NADPH-diaphorase activity. In addition, NADPH-diaphorase activity, not related to iNOS immunoreactivity, was observed in astrocytes in both white and grey matter of AIDS and ADC patients. All AIDS and ADC patients, and only one control subject showed characteristic features of apoptotic cell death. CONCLUSIONS: Different forms of NOS are present in microglial cells and astrocytes of AIDS and ADC patients but are largely absent in control subjects. Although more NOS-expressing cells occur in ADC than in AIDS patients, apoptotic cell death was found in both patient groups to the same extent. We postulate that NO production in brains of AIDS patients results in cumulative cortical cell loss, which becomes neurologically evident at later stages of disease and is expressed as ADC.

AIDS Dementia Complex↗
PubMed1999

Reduced prevalence of the CCR5 delta32 heterozygous genotype in human immunodeficiency virus-infected individuals with AIDS dementia complex.

Heterozygosity for a 32-bp deletion in the CCR5 gene (CCR5 Delta32), which encodes the coreceptor for macrophage-tropic non-syncytium-inducing (NSI) human immunodeficiency virus type 1 (HIV-1) variants, results in a lower CCR5 expression and reduced NSI HIV-1 replication. Because infection of macrophages and microglial cells by NSI HIV-1 is considered to be instrumental for the development of AIDS dementia complex (ADC), we studied whether the CCR5 Delta32 heterozygous genotype correlated with a reduced frequency of ADC. Two (4.1%) of 49 patients with ADC versus 27 (14. 5%) of 186 AIDS patients without ADC were heterozygous for CCR5 Delta32 (P=.05). In contrast, a point mutation in the first transmembrane domain of CCR2 (CCR2 64I) did not show this protective effect (P=.57). The reduced prevalence of the CCR5 Delta32 allele among patients with ADC may indicate a reduced or absent reservoir of macrophage-tropic NSI HIV-1 in the brain of CCR5 Delta32 heterozygotes.

AIDS Dementia Complex↗
PubMed1998

[Pain in one leg in patients with cancer].

Two patients, a woman aged 65 years and a man aged 56 years, with cancer, presented with pain in one leg as the first manifestation of metastases. The woman had tumour plexopathy of the lumbosacral plexus caused by an os sacrum metastasis of a thyroid carcinoma; she received radiotherapy but died a short time later. The man had lumbosacral epidural metastases of a colon carcinoma, compressing lumbosacral roots; with radiotherapy he survived the first year. Back pain with radiating pain is a frequent symptom in patients with cancer. Spinal epidural metastases, spinal and paraspinal metastases without epidural extension, tumour plexopathy and leptomeningeal metastases are the commonest causes. Early diagnosis (by MRI or spinal fluid examination) is important; with progressive weakness or sphincter disturbances the prognosis worsens.

Aged↗
PubMed1998

Cerebrospinal-fluid HIV-1 RNA and drug concentrations after treatment with lamivudine plus zidovudine or stavudine.

BACKGROUND: Treatment and prevention of HIV-1-related central-nervous-system disease may be dependent on penetration of antiretroviral drugs into the central nervous system. Few data are available about cerebrospinal-fluid penetration and concomitant changes of HIV-1-RNA concentrations during treatment with antiretroviral agents. We investigated these effects in HIV-1-infected people. METHODS: 28 antiretroviral-naive individuals with CD4 cell counts of 200/microL or more and plasma HIV-1-RNA concentrations of 10,000 or more copies/mL who were free of neurological symptoms were randomly assigned lamivudine plus either stavudine (n = 17) or zidovudine (n = 11). We did lumbar punctures on 28 individuals before and 22 individuals after 12 weeks of treatment to assess HIV-1-RNA and drug concentrations in cerebrospinal fluid. FINDINGS: All 28 individuals had detectable HIV-1-RNA concentrations in the cerebrospinal fluid (median 4.64 log10 copies/mL and 4.20 log10 copies/mL in the lamivudine plus zidovudine and lamivudine plus stavudine groups, respectively). There was no correlation between plasma and cerebrospinal-fluid HIV-1-RNA concentrations (r = 0.18, p = 0.35). After 12 weeks of treatment none of the individuals had detectable HIV-1-RNA concentrations in the cerebrospinal fluid. The highest drug concentration in the cerebrospinal fluid was for lamivudine followed by stavudine and zidovudine. Concentrations were consistent over time, unlike plasma concentrations. Therefore, we found time-dependent cerebrospinal-fluid to plasma drug-penetration ratios, which were highest for zidovudine followed by stavudine and lamivudine. INTERPRETATION: The two drug combinations were equally effective in the decrease of cerebrospinal fluid HIV-1-RNA concentrations. All drugs penetrated the cerebrospinal fluid. Antiretroviral drugs other than zidovudine might be useful in the prevention of AIDS dementia complex.

AIDS Dementia Complex↗
PubMed1998

[Clinical thinking and decision making in clinical practice. A patient with systemic lupus erythematosus and behavioral changes].

A 48-year-old man with systemic lupus erythematosus (SLE) was admitted with fever, headache and mental change. On admission he was treated with daily doses of cyclophosphamide 100 mg and prednisone 7.5 mg. Orientation and attention were diminished and visual examination revealed right-sided homonymous hemianopia. MRI of the brain showed a ring-enhanced, space occupying lesion in the left occipital lobe. An infectious disease cause was considered, because disease activity parameters of SLE were all negative (anti-dsDNA and the complement profile). The anti-Toxoplasma titre was elevated in cerebrospinal fluid (57 IU/ml) and in serum (1140 IU/ml), both IgG. A tentative diagnosis of Toxoplasma encephalitis was made and a trial anti-toxoplasmosis treatment with pyrimethamine and sulfadiazine was administered. Two weeks later the patient was normal at neurological examination and his brain MRI had greatly improved. The anti-Toxoplasma titre had dropped significantly.

Diagnosis, Differential↗
PubMed1998

Reversible blindness in AIDS-related cryptococcal meningitis.

A 30-year-old AIDS-patient with cryptococcal meningitis developed subacute bilateral visual loss associated with high cerebrospinal fluid (CSF) pressure. With immediate CSF drainage the blindness was reversible. The importance of prompt CSF drainage in AIDS-related cryptococcal meningitis with visual failure is stressed.

AIDS-Related Opportunistic Infections↗
PubMed1997

Liposomal amphotericin B (AmBisome) compared with amphotericin B both followed by oral fluconazole in the treatment of AIDS-associated cryptococcal meningitis.

OBJECTIVE: Amphotericin B deoxycholate initial therapy and fluconazole maintenance therapy is the treatment of choice for AIDS-associated cryptococcal meningitis. However, the administration of amphotericin B is associated with considerable toxicity. A potential strategy for reducing the toxicity and increasing the therapeutic index of amphotericin B is the use of lipid formulations of this drug. DESIGN AND METHODS: HIV-infected patients with cryptococcal meningitis were randomized to treatment with either liposomal amphotericin B (AmBisome) 4 mg/kg daily or standard amphotericin B 0.7 mg/kg daily for 3 weeks, each followed by fluconazole 400 mg daily for 7 weeks. During the first 3 weeks, clinical efficacy was assessed daily. Mycological response was primarily evaluated by cerebrospinal fluid (CSF) cultures at days 7, 14, 21 and 70. RESULTS: Of the 28 evaluable patients, 15 were assigned to receive AmBisome and 13 to receive amphotericin B. Baseline characteristics were comparable. The time to and the rate of clinical response were the same in both arms. AmBisome therapy resulted in a CSF culture conversion within 7 days in six out of 15 patients versus one out of 12 amphotericin B-treated patients (P = 0.09), within 14 days in 10 out of 15 AmBisome patients versus one out of nine amphotericin B patients (P = 0.01), and within 21 days in 11 out of 15 AmBisome patients versus three out of eight amphotericin B patients (P = 0.19). When Kaplan-Meier estimates were used to compare time to CSF culture conversion, AmBisome was more effective (P < 0.05; median time between 7 and 14 days for AmBisome versus > 21 days for amphotericin B). AmBisome was significantly less nephrotoxic. CONCLUSIONS: A 3-week course of 4 mg/kg AmBisome resulted in a significantly earlier CSF culture conversion than 0.7 mg/kg amphotericin B, had equal clinical efficacy and was significantly less nephrotoxic when used for the treatment of primary episodes of AIDS-associated cryptococcal meningitis.

AIDS-Related Opportunistic Infections↗
PubMed1997

Severe neurological complications in association with Epstein-Barr virus infection.

Involvement of the nervous system in infectious mononucleosis is common. About 50% have headache on presentation. Neck stiffness without meningitis is a frequent finding. Severe neurological complications are rare though, occurring in fewer than 0.5%. We describe two patients with unusual and severe neurological complications in association with serological evidence of EBV-infection: a 32-year old female developed a bilateral optic neuritis combined with a transverse myelitis and a 72-year old man developed mononeuritis multiplex, autonomic neuropathy and a salt-wasting nephropathy.

Adult↗
PubMed1996

Elevation of cerebrospinal fluid soluble CD27 levels in patients with meningeal localization of lymphoid malignancies.

Diagnosis of meningeal localization of lymphoid malignancies by means of cytologic examination of the cerebrospinal fluid (CSF) can be difficult. Thus far no reliable CSF tumor markers have been identified. CD27 is a transmembrane disulfide-linked 55-kD homodimer present on most peripheral blood T cells and on a subset of B cells. CD27 is also expressed on human malignant B cells and high levels of soluble CD27 can be present in the serum of patients with B-cell malignancies. The aim of this study is to determine prospectively the diagnostic value of CSF sCD27 as a tumor marker in patients with meningeal localization of lymphoid malignancies. CSF sCD27 levels were determined by sandwich enzyme-linked immunosorbent assay. The optimal cut-off value using receiver operator characteristics curves was found to be 10 U/mL. sCD27 levels were normal in all 50 control patients (lumbar disc protrusion) and in 39 of 40 samples obtained from patients with either solid tumors or acute myeloid leukemia. Of 104 CSF samples from 70 children with acute lymphoblastic leukemia (ALL) or non-Hodgkin's lymphoma (NHL) undergoing routine central nervous system (CNS) staging, sCD27 was false positive and false negative in only one sample each. In 70 samples from 45 patients suspected of meningeal localization of ALL or NHL, the sCD27 test had an excellent sensitivity (100%) and specificity (82%). In 7 patients with positive CSF studied longitudinally, sCD27 levels correlated very well with remission and relapse. sCD27 levels were not nonspecifically increased by the administration of cytostatic drugs. Finally, sCD27 was also elevated in the 4 patients studied with primary central nervous system lymphoma (PCNSL). CSF sCD27 is a promising tumor marker in patients with either meningeal localization of lymphoid malignancies or PCNSL, and can be useful in the differential diagnosis of CNS involvement by either lymphoid malignancies or solid tumors.

Adult↗