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Dive into the research topics where Robert J. Gerety is active.

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Featured researches published by Robert J. Gerety.


The New England Journal of Medicine | 1980

Chronic non-A, non-B hepatitis carrier state: transmissible agent documented in one patient over a six-year period.

Edward Tabor; Leonard B. Seeff; Robert J. Gerety

NON-A, non-B hepatitis is a major health problem, present in up to 89 per cent of patients with post-transfusion hepatitis1 and 25 per cent of hospitalized patients with sporadic hepatitis.2 Experi...


Gastroenterology | 1977

Subtyping of Hepatitis B Surface Antigen and Antibody by Radioimmunoassay

Jay H. Hoofnagle; Robert J. Gerety; Linda A. Smallwood; Lewellys F. Barker

The hepatitis B surface antigen (HBSAg) has been shown to possess distinct subtypes adw, ayw, adr, and ayr). A commercially available solid phase radioimmunoassay for antibody to HBSAg (Ausab, Abbott Laboratories North Chicago, Ill.) has been modified to detect the subtypes of HBSAg as well as the subtype-specific anti-HBS reactivities to detect the subtypes of HBSAg as well as the subtype-specific anti-HBS reactivities (anti-d, anti-y, and anti-w). This method has the advantages of general availability, ease of performance, and increased sensitivity over conventional subtyping methods of agar gel diffusion and counterelectrophoresis.


Annals of Internal Medicine | 1983

Concomitant Hepatitis B Surface Antigen and Antibody in Thirteen Patients

P. Gregory Foutch; William D. Carey; Edward Tabor; A. J. Cianflocco; Satoru Nakamoto; Linda A. Smallwood; Robert J. Gerety

Both hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs) were found in 13 patients. Nine patients had HBsAg subtype ad, and 7 had anti-HBs monotypic subtype anti-y. Nine patients had HBsAg before detectable levels of anti-HBs were present. Of the 6 patients whose serum contained subtypes of both HBsAg and anti-HBs, 4 had HBsAg before development of the monotypic antibody. All patients have remained positive for HBsAg and anti-HBs (mean duration, 55.5 weeks). Nine patients were positive for HBeAg, and 7 had renal disease. Six of these seven patients are on hemodialysis. Because of the differing subtype specificities of the circulating HBsAg and anti-HBs, we conclude that HBsAg and anti-HBs occur concomitantly. The presence of HBeAg, which indicates infectivity, is common in our study group, suggesting that these patients are a reservoir for transmission of hepatitis-B-virus infection. Therefore, the presence of anti-HBs alone does not indicate a noninfectious serum. Concomitant HBsAg and anti-HBs seems to be particularly common in patients with renal disease who are on hemodialysis.


The New England Journal of Medicine | 1978

Transmission of Hepatitis B Virus Infection by Transfusion of Frozen-Deglycerolized Red Blood Cells

Harvey J. Alter; Edward Tabor; Harold T. Meryman; Jay H. Hoofnagle; Richard A. Kahn; Paul V. Holland; Robert J. Gerety; Lewellys F. Barker

Chimpanzees were used to determine the ability of prior freezing of red blood cells to prevent the transmission of Type B post-transfusion hepatitis. Four units of human whole blood were each inoculated with 10(6) infectious doses of hepatitis B virus. Although all units became HBsAg negative after freezing and deglycerolization, hepatitis B virus infection developed in all four chimpanzees when these units were transfused. Two of these chimpanzees had only serologic evidence of infection, including the development of HBsAg and antibody to both the hepatitis B surface and core antigens; in these animals, the incubation periods were prolonged (24 to 25 weeks). In contrast, the other two animals also had elevated serum glutamic pyruvic transaminase (peaks of 190 and 461 IU per liter) and had a more rapid onset. There was no hepatitis B virus infection in two nontransfused controls. Our results do not support the use of frozen red blood cells for the prevention of post-transfusion hepatitis.


Gastroenterology | 1979

Acute Non-A, Non-B Hepatitis Prolonged Presence of the Infectious Agent in Blood

Edward Tabor; Milton April; Leonard B. Seeff; Robert J. Gerety

Non-A, non-B hepatitis, previously transmitted to chimpanzees by inoculation of human serum, was serially transmitted through a second and third passage to additional chimpanzees using serum drawn during acute non-A, non-B hepatitis. Sera obtained at weeks 4 and 5 after inoculation from two different chimpanzees, and from one chimpanzee at week 13 after inoculation, were shown to cause elevation of serum aminotransferase levels and abnormal liver biopsies in recipient chimpanzees, with no serologic evidence of hepatitis A or B, cytomegalovirus, or Epstein-Barr virus infection. Serum obtained 3 wk after inoculation did not cause elevation of aminotransferase levels in the recipient chimpanzee, although a single abnormal biopsy was obtained. Thus, the non-A, non-B hepatitis agent was present in serum during acute disease near the time of the first aminotransferase elevation (week 4; perhaps also week 3), and persisted at least until 1 week after the peak aminotransferase level (week 13).


Cancer | 1980

Alphafetoprotein levels of liver cancer patients and controls in a European population.

Dimitrios Trichopoulos; Philip Sizaret; Edward Tabor; Robert J. Gerety; Nicole Martel; Nubia Munoz; George Theodoropoulos

Serum alphafetoprotein (AFP) levels were determined by radioimmunoassay for 80 patients with primary hepatocellular carcinoma (PHC), 40 with metastatic liver cancer (MLC), and 204 controls; all were Caucasians of Greek nationality. Among histologically confirmed PHC cases, 62% had more than 1000 International Units per millilitre (IU/ml) AFP. Only one case with MLC (3%) exceeded 1000 IU/ml AFP, but lower elevations were not uncommon (13%). Among controls, none exceeded 40 IU/ml. Heptitis B surface antigen (HBsAg) was detected among 6% of 17 histologically confirmed PHC patients with AFP less than 100 IU/ml and 60% of 63 PHC patients with more than 100 IU/ml of AFP (P < 0.001). Control subjects positive for HBsAg had significantly higher AFP values compared to those negative for it (P < 0.01) and male controls had slightly higher AFP values compared to those negative for it (P < 0.01) and male controls had slightly higher AFP values than female controls.


Gastroenterology | 1975

Hepatitis B Surface Antigen (Hbs Ag) Subtypes and Indices of Clinical Disease

Robert J. Gerety; Jay H. Hoofnagle; Donald F. Nortman; Lewellys F. Barker

Serial serum samples of prospectively studied patients exposed to plasma containing both adw and ayw subtypes of hepatitis B surface antigen (HBS Ag) were studied for the relationship of HBS Ag subtype to several indices of clinical type B hepatitis. Seventy-four patients circulated HBS Ag that could be subtyped; 50 subtype adw, 22 ayw, and 2 adyw. Although the average incubation period among adw cases was shorter than among ayw cases (P less than 0.05), no additional significant differences were detected between these two groups of patients when analyzed for severity and chronicity of disease. The chronic HBS Ag carrier state developed in 16% (8 of 50) adw cases and in 9% (2 of 22) ayw cases, but this difference was not statistically significant. Judging from these data, it was concluded that the severity and outcome of type B hepatitis are probably independent of HBS Ag subtypes d and y.


Annals of Internal Medicine | 1981

Hepatitis B Transmission Between Dental or Medical Workers and Patients

Robert J. Gerety

Excerpt Hepatitis B is a hazard for dental and medical workers who directly or indirectly acquire the infection from their patients. The risk is higher for urban dentists and physicians and increas...


Intervirology | 1981

Nondetection of Infectious Hepatitis B Virus in a Human Hepatoma Cell Line Producing Hepatitis B Surface Antigen

Edward Tabor; Jennifer A. Copeland; G.F. Mann; Colin R. Howard; Jacinta Skelly; Philip Snoy; Arie J. Zuckerman; Robert J. Gerety

The PLC/PRF/5 human hepatoma cell line producing hepatitis B surface antigen (HBsAg) was studied to determine whether infectious hepatitis B virus (HBV) was also being produced. 2 chimpanzees with no previous exposure to HBV and no serologic markers of past or active HBV infection were inoculated intravenously with 50 ml of either tissue culture supernatant fluid (357 ng/ml HBsAg) or a suspension of cells disrupted by repeated freeze-thaw cycles (57 ng/ml HBsAg). No evidence of HBV infection was detected in either chimpanzee during 6 months of evaluation. This study suggests that the expression of a portion of the HBV genome, when a portion or all of that genome has been incorporated into a host cell, can result in the production of HBsAg without infectious HBV. If it becomes possible to produce a similar expression of this portion of the genome by itself in nonmalignant cells, HBsAg without HBV may be produced in vitro for use in hepatitis B vaccines.


Transfusion | 1980

Viral hepatitis markers in Soviet and American blood donors.

Paul V. Holland; T. Golosova; Wolf Szmuness; E. Ketiladze; Robert H. Purcell; P. Budnitskaya; Robert J. Gerety; T. Vorozhbieva; Edward J. Harley; V. Burlev; Harvey J. Alter; A. Margolina; E. Lubashevskaya

A cooperative study was undertaken to compare the frequency of hepatitis viral antigens and antibodies among blood donors in the Soviet Union and the United States. Age‐ and sex‐stratified blood donors were identified and their sera tested for hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti‐HBs), antibody to the hepatitis B core antigen (anti‐HBc), and antibody to the hepatitis A virus (anti‐HAV). A total of 994 Soviet blood donor sera from five different regions and 1,178 American donor sera from six different regions were tested in the USA. Among the Soviet donors, 450 (45%) had some marker of exposure to the hepatitis B virus; while among the American donors, 94 (8%) did. Of the Soviet donors 848 (85%) were positive for anti‐HAV, compared with 403 (34%) of the American donors. For 1,977 serum samples that were evaluated in both countries for HBsAg, techniques in the USSR identified 36 HBsAg‐positive samples, while the technique in the USA found 38 HBsAg‐positive samples; however, only 24 were judged to be HBsAg‐positive by assays in both countries. Testing of these same 1,977 sera for anti‐HBs revealed that the radioimmunoassay used in the USA identified many more antibody‐positive donors than the immuno‐autoradiography technique used in the Soviet Union. When a portion of the sera were tested by similar radioimmunoassay techniques in each country, there was comparability of results for anti‐HBs, as well as for anti‐HAV, and anti‐HBc. The results permit calculation of age and sex prevalence of hepatitis B and hepatitis A serologic markers for blood donors within and between each country. They also allow comparison, on the same sera, of test methodologies in use in the Soviet Union and in the United States.

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Edward Tabor

Food and Drug Administration

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Lewellys F. Barker

Food and Drug Administration

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Jay H. Hoofnagle

National Institutes of Health

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Robert H. Purcell

National Institutes of Health

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Linda A. Smallwood

Food and Drug Administration

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Belinda Seto

Food and Drug Administration

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Jacques Drucker

National Institutes of Health

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Philip Snoy

Food and Drug Administration

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Daniel R. Jackson

Food and Drug Administration

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