Biomedical subjects
J L Melnick
Publications and source records attributed to J L Melnick.
Human enteroviruses in oysters and their overlying waters.
The presence of enteroviruses in oysters and oyster-harvesting waters of the Texas Gulf coast was monitored over a period of 10 months. Viruses were detected in water and oyster samples obtained from areas both open and closed to shellfish harvesting. Viruses were detected periodically in waters that met current bacteriological standards for shellfish harvesting. No significant statistical relationship was demonstrated between virus concentration in oysters and the bacteriological and physiochemical quality of water and shellfish. Viruses in water were, however, moderately correlated with total coliforms in water and oysters and with fecal coliforms in oysters. Total coliforms in water were realted to total coliforms in sediment were related only to total coliforms in sediment. Among the physiochemical characteristics of water, turbidity was related statistically to the organic matter content of water and to fecal coliforms in water. There was a marked effect of rainfall on the bacteriological quality of water. Of a total of 44 water samples, 26 yielded virus in concentrations from 4 to 167 plaque-forming units per 100-gallon (ca. 378.5-liter) sample. Of a total of 40 pools of 10 to 12 oysters each, virus was found in 14 pools at a concentration of 6 to 224 plaque-forming units per 100 g of oyster meat. On five occasions, virus was found in water samples when no virus could be detected in oysters harvested from the same sites. This study indicates that current bacteriological standards for determining the safety of shellfish and shellfish-growing waters do no reflect the occurrence of enteroviruses.
Concentration of viruses from water by membrane chromatography.
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Cervical cancer cell lines containing herpesvirus markers.
Five epithelioid cell lines were established from invasive cervical carcinoma tissue and were examined for herpes simplex virus (HSV) antigens or virus-induced changes. Immunofluorescence studies with antiserum to an HSV type 2 nonstructural polypeptide detected perinuclear antigens. In these cell lines, concentrations of a membrane fucopeptide that is regularly present in normal cells were reduced to levels similar to those previously observed in virus-transformed cells. One of the cell lines inoculated into athymic mice produced tumors.
Detection of herpesvirus type-specific antibody by a micro solid phase radioimmunometric assay.
A micro solid phase radioimmunometric assay has been developed which measures type-specific antibody in human sera to herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). The test is performed by coating wells of microtiter plates with purified HSV-specified glycoproteins, VP123 and VP119, derived from HSV-1- and HSV-2-infected cells, respectively. The coated wells are then incubated with diluted unadsorbed sera and subsequently with radioiodinated goat anti-human IgG reagent. Because these major viral envelope glycoproteins contain type-specific antigenic determinants, type-specific antibodies are preferentially detected in our assay.
[Taxonomy of viruses, 1975].
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Persistence of virus shedding in asymptomatic women after recovery from herpes genitalis.
One hundred seventeen women were reexamined within 6 months after presenting with genital herpes. Swabs for virus isolation were taken from the cervix whether or not lesions were observed. Herpesvirus type II was isolated from 30 of 67 patients with recurrent disease, but also from 5 of 50 women during periods when there were no signs or symptoms of illness. The epidemiologic importance of virus shedding from asymptomatic women is discussed.
Taxonomy of viruses, 1979.
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Treatment of genital herpes simplex virus infection with photodynamic inactivation.
A double-blind randomized study to evaluate the effect of proflavine in the treatment of genital herpesvirus infection was conducted. One hundred fifty-seven women were studied, of whom 75 were treated with proflavine (treated women) and 82 were treated with placebo (control group). There were 62 women with primary disease and 95 with recurrent infection. Under the conditions by which this study was conducted, there was no apparent difference in the time of healing of lesions, development of recurrences, or virus isolation following treatment in the proflavine-treated and control groups.
Immunohistochemical and electron microscopic detection of hepatitis B surface and core antigens.
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Vaccines and vaccine policy: the poliomyelitis example.
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Viral vaccines: new problems and prospects.
The problems are many: how best to apply the swine flu lessons to the Russian flu "invasion;" whether enough is known about the cytomegalovirus to attempt vaccine development; how to deliver established vaccines to the millions who need them.
Cellular and humoral immunity in guinea pigs to two major polypeptides derived from hepatitis B surface antigen.
Guinea pigs immunized with hepatitis B surface antigen (HBsAg), types adw, adr and ayw, and with two major polypeptides derived from HBsAg/adw developed cell-mediated immunity as determined by the macrophage migration inhibition assay. Peritoneal exudate cells from animals immunized with a 22000- or a 25000-mol. wt. polypeptide derived from HBsAg/adw showed significant migration inhibition after challenge with either polypeptide or with purified HBsAg. Significant inhibition of macrophage migration was not observed when polypeptide-sensitized cells were challenged with normal human serum or with normal human liver extract. Similarly, a cell-mediated immune response was not observed in peritoneal exudate cells from animals sensitized to normal human serum or normal human liver extract which were challenged with either of the polypeptides. The humoral immune response to either of the polypeptides, as measured by radioimmunoassay, was substantially lower than that observed in animals immunized with intact particles. This apparent difference between cellular and humoral responses suggests that the macrophage migration assay is a sensitive indicator of the immunogenicity of the smaller mol. wt. HBsAg-derived polypeptides in guinea pigs.
The fate of parental herpesvirus DNA after infection with normal and photoinactivated virions.
The fate of the 3H-dT-labelled parental DNA of normal and photoinactivated herpes simplex virus type 1 (KOS strain) was followed for 8 h after infection. The sedimentation coefficients of parental virus DNA from cells infected with normal virons increased and became associated with the replicative intermediates of HSV-1 DNA. When cultured in 5-bromodeoxyuridine-containing medium, the buoyant density of the normal parental virus DNA shifted to the hybrid region (containing heavy and light molecules) of the caesium chloride density gradient. The parental virus DNA of photoinactivated virions, however, degraded quickly and did not participate in progeny virus DNA replication.
Concentration of enteroviruses from large volumes of tap water, treated sewage, and seawater.
Methods are described for the efficient concentration of an enterovirus from large volumes of tap water, sewage, and seawater. Virus in acidified water (pH 3.5) in the presence of aluminum chloride was adsorbed to a 10-inch (ca. 25.4 cm) fiberglass depth cartridge and a 10-inch pleated epoxy-fiberglass filter in a series at flow rates of up to 37.8 liters (10 gallons) per min. Adsorbed viruses were eluted from the filters with glycine buffer (pH 10.5 to 11.5), and the eluate was reconcentrated by using a combination of aluminum flocculation followed by hydroextraction. With this procedure, poliovirus in large volumes of tap water, seawater, and sewage could be concentrated with an average efficiency of 52, 53, and 50%, respectively. It was demonstrated that this method is capable of detecting surface solid-associated viruses originating from sewage treatment plants. No difference in virus recovery between laboratory batch studies and a set-up with acid-salt injection was found. This unified scheme for the concentration of viruses has many advantages over previously described systems. These include: high operating flow rates, low weight and small size, effectiveness with a variety of waters with widely varying qualities, and filters with a high resistance to clogging.
Concentration of poliovirus from tap water onto membrane filters with aluminum chloride at ambient pH levels.
A method is described for the concentration of an enterovirus from large volumes of tap water by addition of small amounts of aluminum chloride to enhance virus removal by membrane filters. Tap water treated with 2 X 10(-5) M aluminum chloride showed a slight decrease in pH (less than 0.5), a slight increase in turbidity, and enhanced removal of poliovirus by membrane filters. Virus was quantitatively recovered by treating the filters with a basic buffer, and this eluate was reconcentrated to a small volume by adsorption to aluminum hydroxide flocs. Using these procedures, virus from 1,000 liters of water was reduced to a final eluate of 20 to 80 ml with a mean recovery of 70%.
Role of sediment in the persistence of enteroviruses in the estuarine environment.
The survival of four enteroviruses commonly found in sewage effluents was examined when the viruses were adsorped to marine sediments in estuarine water and compared with virus survival in estuarine water alone. Echovirus 1, coxsackieviruses B3 and A9, and poliovirus 1 survived longer when associated with marine sediment. When the estuarine water was polluted with secondarily treated sewage effluent, virus survived for prolonged periods in sediments, but not in the overlaying estuarine water.