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Featured researches published by Mary Hill.


Liver Transplantation | 2004

Prediction of sustained virological response in liver transplant recipients with recurrent hepatitis C virus following combination pegylated interferon alfa‐2b and ribavirin therapy using tissue hepatitis C virus reverse transcriptase polymerase chain reaction testing

Guy W. Neff; Christopher B. O'Brien; Robert Cirocco; Marzia Montalbano; Maria De Medina; Phillip Ruiz; Amr S. Khaled; Pablo A. Bejarano; Kamran Safdar; Mary Hill; Andreas G. Tzakis; Eugene R. Schiff

The optimal duration of therapy for pegylated interferon combined with ribavirin in recurrent Hepatitis C virus (HCV) following liver transplantation is not known. We wanted to determine if testing for HCV in liver tissue by reverse transcriptase polymerase chain reaction (RT‐PCR) was superior in predicting sustained virological response (SVR) in comparison to standard HCV ribonucleic acid (RNA) detection in the serum. All recipients received combination pegylated alpha‐2b interferon (1.5 mcg / kg) and ribavirin (200–600mg / d) therapy for at least 48 weeks of therapy and were found to have nondetectable HCV RNA by PCR serum testing at the end of therapy. Sustained virological response (SVR) was defined as nondetectable serum HCV RNA at 6 months post treatment withdrawal. Ten liver transplant recipients were included in the study; mean time from transplantation was 29.2 months. All had nondetectable serum HCV RNA by RT‐PCR. In hepatic tissue 7/10 patients HCV RNA was found to be positive by RT‐PCR while 3/10 had nondetectable HCV RNA in their liver by RT‐PCR. SVR was attained in all 3/10 that were hepatic tissue HCV PCR negative after 12 months of combination therapy. In conclusion, direct detection of HCV RNA by RT‐PCR of liver tissue appears to more effectively predict SVR following pegylated interferon and ribavirin therapy than the conventional use of serum. (Liver Transpl 2004;10:595–598.)


Journal of Laboratory and Clinical Medicine | 1998

Detection of anti-hepatitis C virus antibodies in patients undergoing dialysis by utilizing a hepatitis C virus 3.0 assay: correlation with hepatitis C virus RNA.

M. De Medina; Mary Hill; H.O. Sullivan; B. Leclerq; J.R Pennell; Lennox J. Jeffers; Reddy Kr; E. R. Schiff; Guido O. Perez

Hepatitis C virus (HCV) infection is endemic in long-term dialysis units. We assessed the performance of a recently developed HCV 3.0 assay for the detection of HCV antibodies in patients undergoing dialysis. The study evaluated 128 patients undergoing long-term maintenance hemodialysis. Anti-HCV was detected by 2.0 and 3.0 enzyme immunoassay (EIA). Results were confirmed with recombinant immunoblot assays (RIBA 2.0 and RIBA 3.0). HCV RNA was detected by using reverse transcriptase-polymerase chain reaction (RT-PCR). Thirty-two patients (25%) were HCV EIA 2.0 positive. Of these, 1 was RIBA 2.0 negative (PCR positive), 3 were indeterminate (3 PCR positive), and 28 were positive (23 PCR positive). Thirty-five (27%) were HCV EIA 3.0 positive. One was RIBA 3.0 negative (PCR positive), 1 was indeterminate (c33c, PCR positive), and 33 were positive (27 PCR positive) by RIBA 3.0. Thus only 1 PCR-positive patient was negative with RIBA 2.0 and 3.0 assays. Two of the 3 RIBA 2.0 indeterminate samples were positive with RIBA 3.0. One remained indeterminate but was HCV RNA positive. In summary, HCV 3.0 EIA detected 4 additional viremic patients but was positive in 6 PCR-negative subjects. A high correlation of the presence of antibody to c33c with HCV RNA (28 of 34, 82%) was found, and it was found in all anti-HCV positive samples and in 1 indeterminate sample. We conclude that the HCV EIA 3.0 test with the supplemental confirmatory RIBA 3.0 test may improve the sensitivity for the detection of anti-HCV. Nevertheless, in potentially immunocompromised patients undergoing dialysis, PCR continues to be the only reliable test for detecting viremia.


Journal of Virological Methods | 2013

Comparison of detection and quantification of HBV DNA in chronic HBeAg negative and positive patients by Abbott RealTime HBV and Roche Cobas TaqMan HBV assays.

Carol J. Morris; Mary Hill; Maria De Medina; Christine Herman; Gavin Cloherty; Paul Martin

Monitoring the serum hepatitis B viral DNA levels with sensitive realtime PCR assays is strongly recommended for the management of patients with chronic HBV infection. This study compares the performance of two realtime HBV quantitative PCR assays with samples from chronic HBeAg(+) and HBeAg(-) patients.


Asaio Journal | 1999

Factors that influence serum hyaluronan levels in hemodialysis patients.

Maria De Medina; Melanie Ashby; Jorge Diego; J. Philip Pennell; Mary Hill; Eugene R. Schiff; Guido O. Perez

Serum hyaluronan levels are increased in dialysis patients. We evaluated several factors that influence serum hyaluronan levels in 184 patients on chronic hemodialysis (duration 2.3 +/- 2.3 [SD] years). The levels were higher than normal in the whole group and in a subgroup of 133 patients without chronic infection, liver disease, or rheumatoid arthritis (215 +/- 19 and 205 +/- 22 microg/L, respectively). There was a tendency for the levels to be higher in a subgroup of patients with hepatitis c virus (HCV) infection. There was no correlation between hyaluronan levels, alanine aminotransferase (ALT), and duration or dose of dialysis. A weak but highly significant negative correlation between serum albumin levels and serum hyaluronan and ferritin levels was seen. The data suggest that chronic inflammation may explain, at least in part, the increased hyaluronan levels found in chronic dialysis patients.


American Journal of Kidney Diseases | 1992

Improved Detection of Antibodies to Hepatitis C Virus in Dialysis Patients Using a Second-Generation Enzyme Immunoassay

Maria De Medina; Carmen Ortiz; Christina Krenc; Jean Leete; David Vallari; Mary Hill; Silvia LaRue; Margarita Jimenez; William Anderson; Eugene R. Schiff; Guido O. Perez

We tested serum samples from 99 patients undergoing maintenance hemodialysis for hepatitis C virus (HCV) antibodies using a first-generation, licensed anti-HCV enzyme immunoassay (EIA) and a second-generation anti-HCV EIA that detect three gene products c100-3, NS3, and core. Specimens that were repeatedly reactive by either or both screening assays were further evaluated by testing with supplemental EIAs and a dot blot immunoassay. There was 87.9% agreement between the licensed HCV EIA and the HCV EIA second generation. HCV EIA Second Generation detected 10 more positive specimens than HCV EIA, for an increase in detection from 33.3% (33/99) to 43.4% (43/99). We conclude that HCV EIA Second Generation improves detection of HCV infection in hemodialysis patients.


International Scholarly Research Notices | 2013

Absence of Hepatitis B Resistance Mutants before Introduction of Oral Antiviral Therapy

Martin Moehlen; Maria De Medina; Mary Hill; Lennox J. Jeffers; Eugene R. Schiff; Paul Martin

Introduction. The aim of this study was to assess whether hepatitis B virus drug resistant mutations antedated the widespread use of nucleos(t)ide analogues in treatment naïve patients. A number of reports have suggested that drug resistant mutants can be detected in apparently treatment naïve patients. Study. Fifty deidentified serum samples collected from 1986 to 1992 from patients with replicative chronic HBV infection at the University of Miami were genotyped and tested for resistance mutations using a line probe assay InnoLiPA HBV DR v2/v3. Serum HBV DNA was measured. All patients had documented chronic HBV infection with a detectable viral load, HBeAg seropositivity, and absence of HIV infection. Results. Of the 50 individuals included, 86% were male, mean age was 40 ± 12 years, and mostly genotype A. The mean HBV DNA was 126 pg/mL (range 6.4 to 557.0). No mutations were identified. Conclusions. The absence of drug induced mutations in these sera collected several years prior to the introduction of oral antiviral therapy suggests that these mutations do not occur in treatment naïve populations. Detection of drug resistance in an apparently treatment naïve subject suggests either unrecognized prior antiviral therapy or infection by an inoculum from a treatment experienced patient.


Journal of Clinical Gastroenterology | 2013

High frequency of genotype D and spontaneous hepatitis B virus genomic mutations among Haitians in a multiethnic North American population.

Cláudia Alves Couto; Cynthia Levy; Carol J. Morris; Mary Hill; Maria De Medina; Mark R. Sanborn; Gavin Cloherty; Eugene R. Schiff; Paul Martin

Goals/Background: The importance of hepatitis B virus (HBV) genotype and mutations has been increasingly recognized. We aimed to determine HBV genotype, precore (PC), and basal core promoter region (BCP) mutations in a HBV multiethnic South Florida population. Study: Samples from 213 patients were tested for HBV-DNA using Abbott RealTime HBV IUO assay, and for mutations using INNO-LiPA assay. Results: Patients were predominantly male (67%); 61 (31%) were African American, 60 (28%) Hispanic, 37 (17%) Haitian, 27 (19%) white non-Hispanic, and 14 (6.6%) Asian. Genotype A was found in 101 (69%), D in 25 (17%), F in 9 (6%), G in 7 (5%), C and E in 6 (4%) each, B in 4 (3%), and H in 2 (1%) patients. Mixed genotypes were detected in 11 patients. Genotype A was more prevalent in all ethnicities except for Asian. Among hepatitis B e antigen (HBeAg)-negative patients (59%), BCP, PC, and combined BCP/PC mutations were found in 30 (37.5%), 13 (16.3%), and 14 (17.5%), respectively. Genotype D was associated with higher frequency of HBeAg-negative status [18/24 (75%) vs. 62/121 (51%) P=0.03] and mutations [16/19 (84%) vs. 40/67 (60%) P=0.04] compared with others. Genotype A was negatively associated with mutations [26/31 (84%) vs. 30/55 (55%), P=0.009]. PC mutations were more common in genotype D (14/19, 73%) compared with genotype A (7/54, 13%, P<0.0001). One-hundred percent and 79% of Asians and Haitians had spontaneous mutations, respectively. All Haitians with genotype D had PC mutations and 3 (50%) had BCP/PC. Conclusions: The present study shows that HBeAg-negative status and spontaneous mutations were more common with genotype D; the presence of genotype D in Haitians was always associated with spontaneous mutations.


Alcoholism: Clinical and Experimental Research | 1995

Hepatitis C Virus in Alcoholic Patients with and without Clinically Apparent Liver Disease

M. E. Coelho-Little; Lennox J. Jeffers; De Bernstein; J. J. Goodman; Reddy Kr; M. De Medina; Xiuming Li; Mary Hill; S. La Rue; E. R. Schiff


Gastroenterology | 1991

Interferon-induced chronic active hepatitis?

Marcelo Silva; K. Rajender Reddy; Lennox J. Jeffers; Mary Hill; Eugene R. Schiff


Journal of Clinical Microbiology | 2000

A Multicenter Study Evaluation of the Digene Hybrid Capture II Signal Amplification Technique for Detection of Hepatitis B Virus DNA in Serum Samples and Testing of EUROHEP Standards

Hubert G. M. Niesters; Mel Krajden; Lynda Cork; Maria De Medina; Mary Hill; Edwin Fries; Albert D. M. E. Osterhaus

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