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N V Sipsas

Publications and source records attributed to N V Sipsas.

16 recordsLinked to original sources
PubMed2002

Extranodal non-Hodgkin lymphoma presenting as a soft tissue mass in the proximal femur in a HIV(+) patient.

Primary soft tissue non-Hodgkin lymphomas (NHL) are very rare especially among HIV-1 infected patients. We describe a patient with HIV-1 infection who presented with acute pain of the right proximal femur. The clinical and laboratory investigation revealed a high grade centroblastic B-cell lymphoma of soft tissue. The patient was treated by surgical resection of the tumor, chemotherapy and local radiotherapy with no serious side effects. After 36 mdnths of follow up he is in excellent clinical condition, with his lymphoma in complete remission.

Adult↗
PubMed2001

Mixed cryoglobulinemia is associated with increased risk for death, or neoplasia in HIV-1 infection.

BACKGROUND: Cryoglobulinemia has been reported in several chronic infectious and autoimmune diseases, and in patients with HIV-1 infection. Cryoglobulinemia associated with hepatitis C virus infection is considered a risk factor for the development of neoplasia, especially B-cell non-Hodgkin lymphoma. This study was undertaken to investigate whether the presence of circulating cryoglobulins is associated with survival or development of neoplastic disease in HIV-1 infection. DESIGN: We evaluated 87 unselected consecutive HIV-1 infected patients for the presence of cryoglobulinemia and they were prospectively followed up for a median of 34 months, with clinic visits at 4-month intervals. None of the patients had neoplasia at study entry. Time-to-event analysis for death, neoplasm and B-cell lymphoproliferative disorder were performed with Cox proportional hazards models. RESULTS: Mixed cryoglobulinemia (types II and III) was detected in 24 (28%) of the 87 patients. During the follow up, 12 patients died and 8 developed neoplastic disease. Multivariate analysis showed that circulating cryoglobulins were an independent predictor of death [relative risk (RR), 4.97; 95% confidence intervals (CI), 1.26-19.63] and development of neoplasia (RR, 5.18; 95% CI, 1.23-21.83). In addition, cryoglobulinemia reached borderline significance as a predictor of lymphoproliferative disorder of B-cell origin (P = 0.08; RR, 4.53; 95% CI, 0.83-24.75). CONCLUSIONS: Our results suggest that cryoglobulinemia is associated with an increased risk for death, neoplasia or development of lymphoproliferative disorder of B-cell origin, in HIV-1 infected patients.

Adult↗
PubMed2001

Lactobacillus rhamnosus endocarditis complicating colonoscopy.

We report the first case of endocarditis caused by Lactobacillus after an uneventful colonoscopy. The initial empiric treatment with the standard regimen of penicillin-aminoglycoside failed; subsequent treatment with a combination of antibiotics, selected according to the in vitro studies, was successful.

Aged↗
PubMed2001

Sternal tuberculosis after coronary artery bypass graft surgery.

We report a case of sternal tuberculosis following sternotomy, which was performed during coronary artery bypass graft surgery. Although pre-operative evaluation revealed signs of asymptomatic tuberculosis of the lung, isoniazid chemoprophylaxis was not instituted, and the patient developed active tuberculosis in both the lung and sternum 5 y later.

Coronary Artery Bypass↗
PubMed2000

Moraxella catarrhalis endocarditis: case report and review of the literature.

A case of bacterial endocarditis caused by Moraxella catarrhalis in an apparently immunocompetent Greek male is presented, which was diagnosed after a 2-month history of low-grade fever of unknown origin. The agent seems to be a rare pathogen, but due to the high mortality rate, it should always be considered in the differential diagnosis of relevant cases. Beta-lactamase production by many strains complicates the choice of antibiotic.

Adult↗
PubMed2000

Inhibition of human immunodeficiency virus type 1 replication in primary CD4(+) T lymphocytes, monocytes, and dendritic cells by cytotoxic T lymphocytes.

We demonstrate that human immunodeficiency virus type 1 (HIV-1)-specific CD8(+) cytotoxic T lymphocytes (CTL) suppress HIV-1 replication in primary lymphocytes, monocytes, and dendritic cells individually. Viral inhibition is significantly diminished in lymphocyte-dendritic cell clusters, suggesting that these clusters in vivo could be sites where viral replication is more difficult to control by CTL.

CD4-Positive T-Lymphocytes↗
PubMed1999

Processing of HIV-1 envelope glycoprotein for class I-restricted recognition: dependence on TAP1/2 and mechanisms for cytosolic localization.

Processing of viral proteins for recognition by CTL involves degradation of the proteins in the cytosol of an infected cell followed by transport of the resulting peptides into the endoplasmic reticulum (ER) by the TAP1/2 complex. Uncertainty exists over the site of processing of viral envelope (env) proteins since the extracellular domains of env proteins are not present in the cytosol where the class I Ag-processing pathway begins. Rather, the ectodomains of env proteins are cotranslationally translocated into the ER during biosynthesis. To analyze env protein processing, we used the herpes simplex virus protein ICP47 to block peptide transport by TAP1/2 and examined the effects of TAP blockade on the processing of the HIV-1 env protein. For the majority of env-specific CD8+ CTL, the processing pathway required TAP1/2-mediated transport of cytosolic peptides into the ER. To determine how env peptides are generated in the cytosol, we analyzed the processing of two TAP1/2-dependent epitopes containing N-linked glycosylation sites. In each case, processing involved glycosylation-dependent posttranslational modification of asparagine residues to aspartic acid. These results are consistent with cotranslational translocation of env into the ER, where glycosylation occurs. This is followed by export of a fraction of the newly synthesized protein into the cytosol, where it is deglycosylated, with conversion of the asparagines to aspartic acid residues. Following cytoplasmic proteolysis, env peptides are retransported by TAP1/2 into the ER, where association with class I occurs. Thus, the env protein can enter the class I pathway through multiple distinct processing mechanisms.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Circulating autoantibodies to erythropoietin are associated with human immunodeficiency virus type 1-related anemia.

In a cohort of 204 unselected consecutive human immunodeficiency virus type 1 (HIV-1)-infected patients, the association of circulating autoantibodies to endogenous erythropoietin (EPO) with HIV-1-related anemia was studied. Circulating autoantibodies to EPO were present in 48 (23.5%) of the 204 patients studied. Circulating autoantibodies were an independent predictor of anemia (odds ratio [OR]=5.0; 95% confidence interval [CI], 2.5-9.9), as strong as other known causes of anemia. The association of anti-EPO antibodies with anemia became stronger when the analysis was limited to the group of patients without any medical condition causing anemia (OR=10.4; 95% CI, 3.2-33.9). Moreover, the effect on hemoglobin levels remained significant even after adjusting for other anemia parameters. Anti-EPO autoantibodies were associated with higher EPO levels (r=.25, P=.012) and with a more prominent EPO response to anemia. Our findings suggest that autoimmunity, among other factors, may contribute to the pathogenesis of HIV-1-related anemia.

Adolescent↗
PubMed1997

Identification of type-specific cytotoxic T lymphocyte responses to homologous viral proteins in laboratory workers accidentally infected with HIV-1.

Characterization of the cytotoxic T lymphocyte (CTL) response against HIV-1 has been limited by the use of target cells expressing viral proteins from laboratory isolates of HIV-1. This approach has favored identification of group-specific CTL responses and precluded assessment of the extent of type-specific CTL responses directed against HIV-1. Using cells expressing viral proteins from the HIV-1 IIIB strain, we performed a detailed characterization of HIV-1-specific CTL response in three laboratory workers accidentally infected with HIV-1 IIIB. Eight of the epitopes identified were group specific, lying in relatively conserved regions of Gag, reverse transcriptase, and envelope. Three type-specific epitopes were identified, two of them in highly variable regions of envelope. In longitudinal studies in one subject, seven different epitopes and five different restricting HLA class I alleles were identified, with a progressive increase in the number of CTL epitopes recognized by this subject over time. Our data demonstrate that type-specific CTL responses make up a significant proportion of the host cellular immune response against HIV-1 and that a broadening of epitope specificity may occur.

Accidents, Occupational↗
PubMedDate not supplied

Echocardiographic findings in patients with temporal arteritis: apropos of one case of temporal arteritis-associated verrucous (Libman-Sachs) endocarditis.

We report the case of a 70-year-old patient who presented with fever of unknown origin. The initial diagnosis was infective endocarditis as a mitral valve vegetation was found in a transesophageal echocardiogram. Lack of response to empiric antibiotic treatment and further diagnostic work-up established the correct diagnosis of marantic endocarditis due to temporal arteritis. Treatment with steroids and aspirin led to rapid clinical improvement and disappearance of the vegetation. Apropos of this case, we reviewed the records of 25 patients with a new diagnosis of temporal arteritis and analyzed the echocardiographic findings in comparison to those of 40 age- and sex-matched controls. Abnormal echocardiographic findings were present in 13 (52%) out of 25 patients with temporal arteritis and in 5 (12.5 %) out of 40 controls (p < 0.001, chi-square test).

Aged↗