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D D Porter

Publications and source records attributed to D D Porter.

At least 55 records · Page 3Linked to original sources
PubMed1980

Legionella pneumophila: identification in tissue sections by a new immunoenzymatic procedure.

A modified glucose oxidase immunoenzyme technique was shown to be highly sensitive and specific for detection of serogroup 1 Legionella pneumophila in 4% formaldehyde solution-fixed, paraffin-embedded tissue sections. There was complete concordance between infection with L pneumophila and detection of the organisms in tissue sections by glucose oxidase immunoenzyme staining. The L pneumophila organisms stained blue-black and were found within phagocytic cells as well as in the extracellular space. A cloud of blue-black pigment, probably representing diffusable antigen, was present in the extracellular spaces in the area of L pneumophila localization. No false-positive or false-negative reactions were found. This technique requires no specialized equipment, may be applicable to retrospective diagnostic problems, and can be adapted to routine diagnostic practice.

Animals↗
PubMed1979

Adenovirus hepatitis in an immunosuppressed adult patient.

The role of adenovirus as an etiologic agent of hepatic damage has been controversial. A fatal case of adenovirus infection with fulminant hepatitis in a young immunosuppressed adult patient is presented. Intranuclear inclusions were confined to the liver. Electron microscopy revealed crystalline arrays of virions within hepatocytes. This is apparently the first reported case of adenovirus hepatitis occurring in an adult. Adenovirus hepatitis represents another hazard for the immunosuppressed patient.

Adenoviridae Infections↗
PubMed1979

Improvement of the glucose oxidase immunoenzyme technic. Use of a tetrazolium whose formazan is stable without heavey metal chelation.

Glucose oxidase immunoenzymatic localization provides a simple way to show antigens in mammalian tissues, with no need for the quenching of endogenous nonspecific staining. The method is useful for the demonstration of many antigens in formalin-fixed, paraffin-embedded tissues. Improvement of this technic by the use of p-nitro blue tetrazolium chloride (NBT) as the disclosing reagent provides a stable, finely grained localization not possible with the previously used thiazolyl blue (MTT). The described modification makes available an ideal immunoenzymatic stain for the study of tissues at the level of the light microscope. This stain is especially useful for the examination of tissues with hemorrhagic or inflammatory lesions, since there is no endogenous background staining. Slides are permanent, and the technic can be used with peroxidase-labeled antibody to localize two antigens in the same tissue.

Animals↗
PubMed1979

Immunoprophylaxis of respiratory syncytial virus infection in the infant ferret.

Infant ferrets can be protected from respiratory syncytical virus challenge at 3 days of age by gestational infection of their mothers. Ferrets acquire their immunity to respiratory syncytial virus postpartum via immunizing products of lactation. The level of protection against viral replication correlates with the maternal serum neutralizing titer or a concomitant factor. Passive administration of adult ferret serum with a neutralizing titer of 1:1024 or greater, either i.p. or orally does not confer immunity. A nonantibody-mediated protective mechanism appears to play an important role in protecting the infant ferret from respiratory syncytial virus replication. Our findings allow the testing of the efficacy of future human vaccines before human clinical trial.

Aging↗
PubMed1979

Ontogeny of the ferret humoral immune response.

Infant ferrets are born with nearly undetectable immunoglobulin levels, but by 9 days of age the infant ferret serum contains 77, 29, and 13% of adult mean serum levels of IgG, IgA, and IgM. Transmucosal uptake of IgG by the infant ferret occurred for the first 30 days of life. The specific anti-respiratory syncytial virus neutralizing titer of whole milk was 5.5 times higher than maternal serum despite a lower concentration of immunoglobulins in the milk.

Animals↗
PubMed1978

Increased plasma kallikrein activity and tumour growth suppression associated with intralesional bradykinin injections in hamsters.

Daily intralesional injections of bradykinin (250 microgram) into syngeneic SV40 virus-induced fibrosarcomas in inbred hamsters for 21 days produced marked inhibition of tumour growth, marked lymphoid cell infiltration of tumours, and significant elevations in plasma kallikrein and prekallikrein activity, compared with intralesional saline injections. All tumours were of comparable size and growth rates before injections were begun. Plasma kallikrein levels of animals which received the standard tumour cell inoculum subcutaneously and did not develop tumours were elevated significantly above normal levels and above levels of animals with large tumours. Kallikrein inhibitor activity of animals which did not develop tumours was depressed below normal levels. Intralesional injections of saline produced a significantly lesser response in plasma kallikrein and plasma prekallikrein activity than was encountered with subcutaneous saline injections in normal animals. Intralesional injections of bradykinin produced a response equivalent to that encountered with subcutaneous bradykinin injections in normal animals.

Animals↗
PubMed1977

Estradiol-induced redistribution of lysosomal proteins in rat preputial gland. Evidence from immunologic probes.

The influence of estrogen on the subcellular localization and distribution of lysosomal components of preputial gland was investigated in the ovariectomized rat. Antisera of high titer and specificity toward high-density lysosomal lipoproteins of this organ were raised in rabbits. The immunologic effectiveness of the IgG fraction so obtained was confirmed by microcomplement fixation, immunodiffusion, and immunoelectrophoresis. By both direct and indirect immunofluorescence techniques, cryostat sections of preputial gland from the control animals exhibited pinpoint cytoplasmic fluorescence, of dimensions corresponding to those of lysosomes. In contrast, specific immunoreactive material in corresponding target cells from animals receiving 0.1 microng of estradiol-17 beta/100 g body wt only 2 min earlier was distributed more homogeneously, indicating release of antigen from the membrane-bounded organelles. Moreover, specific immunofluorescence became evident at cell surfaces and in peri- and supranuclear localization, sites essentially negative in the controls. These effects were intensified at 15 min, as well as by maximal physiologic dose (0.5 microng/100 g body wt) of hormone. The relatively less active epimer, estradiol-17 alpha, exhibited only very limited effectiveness by some of these criteria. These observations, taken together with independent biochemical and ultrastructural evidence, lead to the conclusion that structural labilization of lysosomal constituents and their translocation to the nuclear compartment are early correlates of estrogen action.

Animals↗
PubMed1977

Isolation of Aleutian disease virus of mink in cell culture.

Aleutian disease virus, the causative agent of a persistent infection in mink, was isolated in a continuous line of feline renal cells when the cultures were maintained at reduced temperature (31.8 degrees). After serial in vitro passage of the virus at this temperature it had an optimum replication temperature of 37 degrees. An immunofluorescence focus assay was found to be suitable for virus quantitation. The cultured virus reproduced Aleutian disease in mink, and the virus could be reisolated from the mink 10--180 days after inoculation. The properties of the virus suggest that it is a member of the parvovirus group.

Aleutian Mink Disease Virus↗
PubMed1977

A comparative study of detection methods for Aleutian disease viral antibody.

Four methods of detecting and quantitating mink antibody against Aleutian disease (AD) virus were compared. Counterelectrophoresis, modified, counterelectrophoresis, immunofluorescence, and complement fixation were performed blindly on 274 serum samples. All four methods were reliably specific for AD antibody. Immunofluorescence was less reproducible than the other systems. Immunofluorescence complement fixation were 4- to 8-fold more sensitive than regular or modified counterelectrophoresis, but were limited by background staining and anti-complementary activity, respectively, when used to detect small amounts of antibody in undiluted sera.

Aleutian Mink Disease↗
PubMed1977

Reduced severity of lesions in mink infected transplacentally with Aleutian disease virus.

Inoculation of mink late in the second trimester of pregnancy with Aleutian disease virus (ADV) produces a persistent infection in the offspring. When these mink were analyzed at 83 days of age and compared with adolescent mink infected for a similar length of time, the transplacentally infected mink show: 1) a marked reduction in plasmacytosis, immunoglobulin level and specific ADV antibody; 2) increased amounts of infectious ADV and numbers of cells containing viral antigen; 3) a marked reduction in immune complex glomerulonephritis and absence of immune complex arteritis; 4) free ADV antigen in the glomeruli; and 5) a striking accumulation of eosinophils in the tissues. The findings suggest that the degree of ADV expression is partially immunologically controlled.

Aging↗
PubMed1976

The pathogenesis of respiratory syncytial virus infection in infant ferrets.

The infant ferret is susceptible to respiratory syncytial virus infection in both the upper and lower respiratory tracts. In the nose, viral replication is restricted to the surface respiratory epithelium in the nasal passages and turbinates. In the lungs, viral replication is of a lower order of magnitude and is localized in the alveolar cells. The pattern of viral replication in nasal tissues is independent of the age of the animal at infection, whereas the pattern in lung tissues shows a striking age dependence, with viral replication progressively decreasing as a function of age. Thes age dependence appears to be due to an intrinsic age-related mechanism yet to be defined. We feel that the infant ferret is an acceptable model for the study of respiratory syncytial virus disease and that the study of age dependence observed in ferrets may allow elucidation of the mechanisms involved in the age dependence seen in humans.

Aging↗
PubMed1975

Fascioliasis causing hepatitis in two eaters of water cress.

Fasciola hepatica infection of the liver in a husband and wife occurred after they had eaten water cress exposed to pollution by cattle. Diagnosis was a problem. Both responded to treatment with chloroquine and emetine. The epidemilology and pathology of infection of the liver by Fasciola hepatica are described. The danger of eating water cress is emphasized for this momentary delight may lead to a chronic debilitating illness.

Aged↗
PubMed1975

Pathogenesis of aleutian disease of mink: identification of nonpersistent infections.

Aleutian disease virus usually produces a persistent infection and progressive immune comples disease in mink of the Aleutian genotype. Study of Aleutian disease virus infection in non-Aleutian mink showed that about one-quarter developed nonpersistent infections by the virus, and that the nonpersistence was not genetically determined by the host. The nonpersistently infected mink developed only a transient elevation of serum gamma globulin, and much lower specific Aleutian disease virus antibody titers than persistently infected mink. No lesions were found in the nonpersistently infected mink.

Aleutian Mink Disease↗
PubMed1975

Isolation of infectious bovine rhinotracheitis virus from Mustelidae.

Herpesviruses isolated from either domesticated or wild carnivores should be immunologically compared with known viruses of this group which could have been included in the diet of the animal before being considered to be previously undescribed herpesviruses native to the carnivore in question.

Animals↗
PubMed1975

Cryostat microtomy of lung tissue in an expanded state.

A technique is reported for cryostat sectioning of lung tissue in an expanded state for use in viral immunofluorescence studies. A 1:2 mixture of O.C.T. embedding compound and phosphate-buffered saline is injected intratracheally into fresh lung tissue. The lung tissue is frozen in liquid nitrogen and sectioned with a cryostat. Compared to other published reports of lung sectioning for immunofluorescence microscopy, this method has the advantages of being easy and quick, maintaining the lung sections in an expanded rather than collapsed state and avoiding contact with chemicals potentially capable of altering sensitive viral antigen.

Animals↗