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Biomedical subjects

Belinda Yen-Lieberman

Publications and source records attributed to Belinda Yen-Lieberman.

At least 19 recordsLinked to original sources
PubMed2006

JC virus chromogenic in situ hybridization in brain biopsies from patients with and without PML.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by the JC polyoma virus. Electron microscopy and immunohistochemistry are the traditional methods of confirming the presence of the virus in brain biopsies from these patients. We studied the brain biopsies from 7 patients with PML and 6 patients without PML with chromogenic in situ hybridization (CISH) for the JC polyoma virus using a commercially available probe. The biopsies from the patients with the PML cases were proven to contain the JC polyoma virus by traditional and molecular methods. The CISH findings were compared with the known state of infection. All (7/7) of the biopsies from patients with PML were positive for the presence of polyoma virus by CISH, whereas the biopsies from patients without PML were uniformly negative. CISH seems to be a useful tool for the detection of the JC virus in brain biopsies from patients with PML, and is more accessible because a commercial probe is available.

Brain↗
PubMed2005

Clinical utility of cytomegalovirus viral load in bronchoalveolar lavage in lung transplant recipients.

The utility of cytomegalovirus (CMV) viral load (VL) by quantitative hybrid capture assay (Q-HCA) was investigated in bronchoalveolar lavage (BAL) from lung transplant recipients and compared with BAL cultures and blood VL. Forty-three consecutive BAL samples from 27 lung transplant recipients were analyzed. All samples had shell vial (SV) cultures in addition to Q-HCA. Histopathology was done on all lung tissues, and immunohistochemistry (IHC) in those with positive CMV cultures. Fifteen (56%) lung transplant recipients had both positive BAL SV cultures and BAL VL. Five of 15 had CMV pneumonitis with a VL in BAL >500 000 copies/mL (mean: 1638 450). Ten patients without CMV pneumonitis had VL in BAL <500 000 copies/mL (mean 81 820, p = 0.002). High VL in BAL and blood invariably meant CMV pneumonitis, but 2 patients with CMV pneumonitis had high BAL VL but relatively low blood VL. Initial CMV seronegativity was associated with pneumonitis (4/5 vs. 1/10; p = 0.004) and higher BAL CMV VL (p = 0.03). High CMV BAL or blood VL did not correlate with acute rejection or development of bronchiolitis obliterans syndrome (BOS). High CMV VL in BAL in lung transplant recipients is strongly associated with CMV pneumonitis, and may be more predictive than peripheral blood viral load.

Adult↗
PubMed2005

Persistent replication of human immunodeficiency virus type 1 despite treatment of pulmonary tuberculosis in dually infected subjects.

Tuberculosis (TB) is the most common life-threatening infection in human immunodeficiency virus (HIV)-infected persons and frequently occurs before the onset of severe immunodeficiency. Development of TB is associated with increased HIV type 1 (HIV-1) viral load, a fall in CD4 lymphocyte counts, and increased mortality. The aim of this study was to examine how treatment of pulmonary TB affected HIV-1 activity in HIV-1/TB-coinfected subjects with CD4 cell counts of >100 cells/mul. HIV-1/TB-coinfected subjects were recruited in Kampala, Uganda, and were monitored over time. Based upon a significant (0.5 log10 copies/ml) decrease in viral load by the end of treatment, two patient groups could be distinguished. Responders (n = 17) had more rapid resolution of anemia and pulmonary lesions on chest radiography during TB treatment. This group had a significant increase in viral load to levels not different from those at baseline 6 months after completion of TB treatment. HIV-1 viral load in nonresponders (n = 10) with TB treatment increased and at the 6 month follow-up was significantly higher than that at the time of diagnosis of TB. Compared to baseline levels, serum markers of macrophage activation including soluble CD14 decreased significantly by the end of TB treatment in responders but not in nonresponders. These data further define the impact of pulmonary TB on HIV-1 disease. HIV-1 replication during dual HIV-1/TB infection is not amenable to virologic control by treatment of TB alone. Concurrent institution of highly active antiretroviral treatment needs to be evaluated in patients dually infected with pulmonary TB and HIV-1.

Adult↗
PubMed2005

Multiplexed particle-based anti-granulocyte macrophage colony stimulating factor assay used as pulmonary diagnostic test.

Pulmonary alveolar proteinosis (PAP) is characterized by the accumulation of lipoproteinaceous material within the lung alveoli. Recent studies indicate that PAP is an autoimmune disease characterized by a neutralizing anti-granulocyte macrophage colony stimulating factor (GM-CSF) antibody. At present the only definitive diagnostic test for PAP is open lung biopsy. We have previously published that anti-GM-CSF is diagnostic for PAP and correlates with disease pathogenesis using a traditional serial anti-GM-CSF antibody titer format (T. L. Bonfield, M. S. Kavuru, and M. J. Thomassen, Clin. Immunol. 105:342-350, 2002). Titer analysis is a semiquantitative method, and often subtle changes in antibody titer are not detectable. In this report we present data to support anti-GM-CSF detection by a quantitative highly sensitive multiplexed particle-based assay which has the potential to be a clinical diagnostic test.

Autoantibodies↗
PubMed2005

Fatal West Nile Virus infection after rituximab/fludarabine--induced remission for non-Hodgkin's lymphoma.

West Nile virus (WNV) infections are potentially life threatening in immunocompromised hosts. Currently, the best diagnostic test is serology. Reverse-transcriptase polymerase chain reaction (RT-PCR) testing has a role, but, because WNV is a cell-associated neurotropic virus, RT-PCR results are frequently negative even in cases of active infection. We present a case in which serology results were persistently negative because the patient was immunocompromised following lymphoma treatment. The role of humoral immunity in resolution of WNV is also discussed.

Antibodies, Monoclonal↗
PubMed2005

New cervical cancer screening strategy: combined Pap and HPV testing.

Our strategy for cervical cancer screeing is being revolutionized by our new understanding of how human papillomavirus (HPV) contributes to carcinogenesis and the natural history of cervical cancer. The American Cancer Society and the American College of Obstetricians and Gynecologists now recommend combined HPV and Papanicolaou (Pap) testing for cervical cancer screening in women age 30 or older. However, although incorporation of HPV DNA testing into primary screening provides clear benefits, it also raises new questions.

Adult↗
PubMed2004

Pharmacokinetic evaluation and short-term activity of stavudine, nevirapine, and nelfinavir therapy in HIV-1-infected adults.

OBJECTIVE: Evaluate pharmacokinetic interaction, short-term safety, and antiretroviral activity of stavudine (d4T), nevirapine (NVP), and nelfinavir (NFV) as combination HIV-1 therapy. DESIGN: Prospective, open-label study investigating the pharmacokinetic interactions between d4T, NVP, and NFV and documenting short-term tolerability and virologic and immunologic activity. METHODS: Twenty-five HIV-1-infected adults, naive to nonnucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs), < or = 6 months of d4T treatment, CD4 > or = 100 cells/mm, and viral load > = 5,000 copies/mL enrolled. All received NFV 750 mg 3 times daily and d4T 30-40 mg twice daily for 1 week, then added NVP at 200 mg once daily for 2 weeks and 200 mg twice daily thereafter. Steady-state pharmacokinetic parameters of NFV, AG1402 (metabolite of NFV), and d4T were compared before and after the addition of NVP. RESULTS: No statistically significant changes in NFV or d4T pharmacokinetics were observed following the addition of NVP. Levels of AG1402 were suppressed 60-70%. Drug-related adverse events were seen at expected rates. At day 36, median viral load suppression was 2.0 log10 and absolute CD4 count increased by 111 cells/mm. CONCLUSIONS: NVP administration did not significantly affect the steady-state pharmacokinetic parameters of NFV or d4T. The combination of d4T, NVP, and NFV induced rapid suppression of HIV-1 viral load and rises in CD4 cell count.

Adolescent↗
PubMed2004

Detection of hepatitis C virus by a user-developed reverse transcriptase-PCR and use of amplification products for subsequent genotyping.

BACKGROUND: Detection, quantitation and genotyping of hepatitis C virus (HCV) are important in selecting appropriate therapy. Current commercially available HCV genotyping kits, including sequencing-based TRUGENE HCV 5'NC and hybridization-based INNO-LiPA HCV II assays, rely on amplification products (amplicons) generated by HCV reverse-transcriptase (RT)-PCR methods such as the Roche AMPLICOR HCV test. METHODS: We developed a one-step RT-PCR assay to amplify and detect HCV RNA, and the resulting amplicons were used for HCV genotyping (TRUGENE). A total of 142 clinical samples were used to compare results from the RT-PCR/TRUGENE assay and those generated by the COBAS AMPLICOR and INNO-LiPA tests. RESULTS: Eighty-seven of 108 plasma specimens which were positive by AMPLICOR were also positive by the user-developed RT-PCR, giving a sensitivity of 100.0%. The RT-PCR detected 2 of 21 AMPLICOR-negative specimens and none of 34 HCV-EIA-negative serum specimens, giving a specificity of 96.4%. The 87 amplicons from the RT-PCR yielded HCV genotypes. HCV genotype results from both TRUGENE and INNO-LiPA were all in agreement. The TRUGENE and INNO-LiPA assays identified 69 (79.3%) and 47 (54.0%) specimens, respectively at the subtype level. HCV subtype information agreed by both assays in 34 of 36 (99.4%) specimens. One specimen with HCV genotypes 2 and 4 by INNO-LiPA was classified as a single genotype 2 by TRUGENE. CONCLUSION: Our data showed that the user-developed RT-PCR has comparable sensitivity and specificity for the detection of HCV in clinical specimens. The amplicons generated by the RT-PCR can be used for HCV genotyping by the sequencing-based TRUGENE assay.

Base Sequence↗
PubMed2004

Detection of polyoma virus in brain tissue of patients with progressive multifocal leukoencephalopathy by real-time PCR and pyrosequencing.

We evaluated 2 methods, a LightCycler PCR assay and pyrosequencing for the detection of the JC polyoma virus (JCV) in fixed brain tissue of 10 patients with and 3 control patients without progressive multifocal leukoencephalopathy (PML). Nucleic acid extraction was performed after deparaffinization and proteinase K digestion. The LightCycler assay differentiates the BK virus (BKV), JCV, and SV40 using melt curve analysis. Conventional PCR was used with the same primers to generate products for pyrosequencing. Two sequencing primers were used that differentiate the polyoma viruses. Seven of 11 biopsies (1 patient had 2 biopsies) with PML were positive for JCV by real-time PCR and/or PCR/pyrosequencing. Three of 4 remaining biopsies were positive by real-time PCR but had melting points between JCV and SV40. The 4 specimens that were negative or atypical by LightCycler PCR were positive by traditional PCR, but 1 had an amplicon of lower molecular weight by gel electrophoresis. These were shown to represent JCV by at least 1 of the 2 pyrosequencing primers. The biopsies from patients without PML were PCR negative. Both the LightCycler and pyrosequencing assays are useful for confirming JCV in brain biopsies from patients with PML, but variant JCVs may require supplementary methods to confirm JCV infection.

BK Virus↗
PubMed2004

Comparison of five methods for extraction of Legionella pneumophila from respiratory specimens.

The efficiencies of five commercially available nucleic acid extraction methods were evaluated for the recovery of a standardized inoculum of Legionella pneumophila in respiratory specimens (sputum and bronchoalveolar lavage [BAL] specimens). The concentrations of Legionella DNA recovered from sputa with the automated MagNA Pure (526,200 CFU/ml) and NucliSens (171,800 CFU/ml) extractors were greater than those recovered with the manual methods (i.e., Roche High Pure kit [133,900 CFU/ml], QIAamp DNA Mini kit [46,380 CFU/ml], and ViralXpress kit [13,635 CFU/ml]). The rank order was the same for extracts from BAL specimens, except that for this specimen type the QIAamp DNA Mini kit recovered more than the Roche High Pure kit.

Bronchoalveolar Lavage Fluid↗
PubMed2004

Correlation between viral loads of cytomegalovirus in blood and bronchoalveolar lavage specimens from lung transplant recipients determined by histology and immunohistochemistry.

Cytomegalovirus (CMV) is an important pathogen in lung transplant recipients. Early detection of CMV end-organ disease should help with treatment management. We determined the CMV viral load by hybrid capture in bronchoalveolar lavage (BAL) fluid samples from patients who had undergone lung transplantation. For 39 of these samples (from 25 patients), corresponding transbronchial biopsy samples were available for CMV immunohistochemistry (IHC). The CMV IHC results were interpreted and categorized as positive or negative, and the positive results were subcategorized as typical if cells with both significant nuclear enlargement or Cowdry A-type inclusions and positive staining were present or as atypical if definitive nuclear staining was seen but significant nuclear enlargement was not. Diagnostic CMV viral inclusions were reported in the anatomic diagnosis, based on hematoxylin-eosin staining alone, for three (8%) of the biopsy samples. CMV was detected by IHC in 13 (33%) samples (5 typical, 8 atypical). The median CMV viral load in BAL samples was 0 copies/ml for BAL samples from patients with IHC-negative biopsy samples; 47,678 copies/ml for BAL samples from patients with biopsy samples with positive, atypical staining; and 1,548,827 copies/ml for BAL samples from patients with biopsy samples with positive, typical staining (P < 0.001). Compared to routine pathology of biopsy samples, the use of IHC increased the diagnostic yield of CMV. Also, the CMV viral load in BAL fluid samples increased along with immunoreactivity from negative to positive, atypical staining to positive, typical staining. The CMV viral load determined with the end-organ sample, the BAL fluid sample, was higher than the corresponding viral load determined with blood. Both IHC and determination of the CMV viral load in BAL samples may be useful for the detection of individuals at risk for the development of fulminant invasive CMV disease.

Bronchoalveolar Lavage Fluid↗
PubMed2003

Rotaviral and bacterial gastroenteritis in children during winter: an evaluation of physician ordering patterns.

BACKGROUND: Identification of the agents of infectious diarrhea may facilitate appropriate therapy and prevent inappropriate antibiotic use. OBJECTIVES: To better define the etiology of infectious diarrhea for children <12 years in our community and to study the ordering patterns of physicians. STUDY DESIGN: We reviewed test results of stool specimens from children <12 years old at our institution (CCF) and those submitted through our reference laboratory for rotavirus enzyme immunoassay (REIA) and stool cultures for a 7-month period (11/1/00-6/1/01). For CCF patients, REIA and stool cultures for usual bacterial enteric pathogens (BEP) were performed, regardless of the test ordered (i.e. REIA alone, stool culture alone or both). We compared the results with the orders placed to determine if requests for rotavirus alone or bacterial stool culture alone missed BEP or rotavirus, respectively. RESULTS: Overall, REIAs were performed on 81% (538/661) of stool specimens, with 37% positive. Stool cultures were performed on 62% (408/661) of stool specimens, with 4.4% positive. Stool specimens (280) from CCF pediatric patients were evaluated for both rotavirus and BEP. Some 42% of REIA and 23% of stool cultures were ordered as single tests, while both tests were ordered for 35% of the patients. Of the REIA ordered alone, 34% were positive for rotavirus; however, 2.5% of these contained BEP that would have been missed. Of the stool cultures that were ordered alone, 8% were positive; however, 19% of these contained rotavirus that would have been missed. When both tests were ordered, 22% contained rotavirus and 2% contained BEP. CONCLUSION: Both rotavirus and bacterial enteric infections were missed with selective viral versus bacterial specific ordering patterns. A rotaviral screen prior to stool culture may be useful for children with diarrhea during the winter months.

Child↗
PubMed2003

Direct comparison of hepatitis C virus genotypes tested by INNO-LiPA HCV II and TRUGENE HCV genotyping methods.

BACKGROUND: Hepatitis C virus (HCV) is a major cause of chronic liver disease worldwide. It is associated with the development of end-stage liver disease and hepatocellular carcinoma. Studies have shown that patients infected with different genotypes of HCV may respond to interferon-ribavirin therapy differently and thus HCV genotype information is very important in helping physicians to better managing their patients. OBJECTIVES: Compare the end results of HCV typing of the two commercially available tests. STUDY DESIGN: TRUGENE Genotyping test (Visible Genetics) was used to analyze clinical specimens obtained from North America. The 5' NC was amplified with the Roche COBAS Amplicor HCV Monitor Test. Amplification products were blinded and genotyped by the TRUGENE HCV 5'NC method. Genotype results were compared with those obtained by the reverse hybridization based INNO-LiPA HCV II (Innogenetics) assay. Additional sequencing of the NS5B region was done to resolve discrepancies. RESULTS AND CONCLUSIONS: Among the total of 110 consecutively collected serum specimens submitted for HCV genotyping, 108/110 could be typed by the sequencing method and 107/110 were typable by LiPA HCV II method. Our experiences with the tests suggest that at type level, HCV genotype results are 100% concordant between the two tests studied for those 106 specimens successfully typed by both methods. More sensitive amplification, such as qualitative PCR, is needed to test specimens with viral load lower than 20000 IU/ml. Both tests can be easily adapted by a clinical diagnostic laboratory.

5' Untranslated Regions↗
PubMed2003

Detection of Legionella pneumophila by real-time PCR for the mip gene.

A real-time PCR assay for the mip gene of Legionella pneumophila was tested with 27 isolates of L. pneumophila, 20 isolates of 14 other Legionella species, and 103 non-Legionella bacteria. Eight culture-positive and 40 culture-negative clinical specimens were tested. This assay was 100% sensitive and 100% specific for L. pneumophila.

Bacterial Proteins↗
PubMed2003

Comparison of molecular tests for detection and quantification of cell-associated cytomegalovirus DNA.

A cell-based standard was developed to compare the COBAS Amplicor CMV Monitor test, the Hybrid Capture System CMV DNA test, and the NucliSens CMV test. The standard was prepared by infecting human foreskin fibroblasts (HFFs) with cytomegalovirus (CMV) strain AD169 at low multiplicity of infection (0.03) and harvesting the cells at 6 h postinfection. Buffy coat cells were added to produce concentrations of from 0 to 10(5) HFFs per 10(6) total cells. Five laboratories performed the Amplicor PCR test and two laboratories performed the NucliSens and Hybrid Capture tests. The Amplicor PCR test was 1.5 to 2.0 log(10) more sensitive than the Hybrid Capture test. The specificities of the Amplicor PCR and Hybrid Capture tests were 100 and 93.8%, respectively. The linear range of the Amplicor PCR and Hybrid Capture tests were 2 to 4.48 log(10) and 3.48 to at least 5.0 log(10) CMV target cells, respectively. The standard deviations of the Amplicor PCR and Hybrid Capture tests varied throughout their linear range, and for both tests the variability was greater for lower concentrations of input CMV DNA. These data allow the direct comparison of viral load values between the Amplicor and Hybrid Capture tests. The analytical sensitivity of the NucliSens test could not be determined by using the 6-h standard, because the low multiplicity of infection and short culture time did not allow for adequate transcription of pp67 late mRNA measured in the test. Extending the incubation time of the standard to 24 h increased the analytical sensitivity of the NucliSens test to 3.0 log(10) target cells.

Cytomegalovirus↗
PubMed2003

New advances transform the management of women with abnormal pap tests.

New advances in Papanicolaou test technology, human papillomavirus DNA testing, and revisions in the Bethesda terminology for cervical cytology have transformed the management of abnormal Pap tests. This approach has been validated by a recent randomized clinical trial, and in some instances can reduce the number of colposcopies by 50%.

Adult↗