B-mode ultrasonographic evaluation of the testis in relation to serum testosterone concentration in male Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) during the breeding season.

The use of ultrasonography as a noninvasive tool for assessing the reproductive status of the male Yangtze finless porpoise (YFP; Neophocaena phocaenoides asiaeorientalis) was validated by correlating ultrasonographically determined testicular volume (TV) and testicular parenchyma pixel intensity (PI) with serum testosterone (T) concentration. The testes of 13 free-ranging male YFPs from the Tian-e-Zhou Reserve and three captive animals from the Baiji Dolphinarium (Wuhan, China) were examined ultrasonographically during April 2008. Testis volume was determined using Lambert's formula for an ellipsoid. Testicular parenchyma PI was evaluated by analyzing testicular ultrasonograms using pixel analysis software (Image J). Serum T concentrations were determined using a single-antibody radioimmunoassay. The TV, PI, and serum T concentration were low and similar in animals with body length <133 cm, highest in those with body length >or=142 cm, and highly variable in those with body length from 133 to 141 cm. Both TV and PI were closely correlated with serum T concentration (r=0.91 and r=0.85, respectively; P<0.01), indicating a consistent association between structural and functional development of the testis. In conclusion, we inferred that puberty onset in male YFPs occurred when TV was >150 cm(3) and PI was >60 during the breeding season and that testicular ultrasonography and pixel analysis was an efficient, noninvasive, real-time tool to evaluate testicular function of live male YFPs.

Role of antiviral antibodies in resistance against coxsackievirus B3 infection: interaction between preexisting antibodies and an interferon inducer.

An experimental model of coxsackievirus B3 infection in newborn mice was utilized to examine the protective role of antiviral antibodies and an interferon inducer, polyinosinic acid-polycytidylic acid [poly(I:C)]. Subcutaneous administration to the infected mice of specific antiviral antibodies resulted in significant protection against coxsackievirus B3 infection. Antibody-treated animals had shortened viremia, early clearance of virus from tissues, and a reduced mortality rate. Dose response to antibodies was clearly demonstrated. However, the time of antibody administration in relation to the infection cycle was important. The protection was observed if antibodies were given before infection (24 h) or shortly after (2 h) infection. Administration of antibodies 24 h after infection resulted in no protection. The interferon inducer poly(I:C) prolonged the survival time of the infected mice, but this protective effect was incomplete and could only be demonstrated in animals treated before infection (24 h) or shortly after (2 h) infection. Enhanced protection against lethal coxsackievirus B3 infection was achieved in animals treated with a combination of antiviral antibodies and poly(I:C). These data confirm that antibody-mediated immunity plays a significant role in resistance against coxsackievirus B3 infection and suggest that antiviral antibodies may interact with poly(I:C) or work independently to produce an enhanced protective effect.

Sensitivity of the virus isolation and immunofluorescent staining methods in diagnosis of infections with herpes simplex virus.

Tissues from marmoset monkeys infected with herpes simplex virus (HSV, Herpes-virus hominis) were utilized to evaluate the relative sensitivity and limitation of the virus isolation technique and the immunofluorescent (fluorescent antibody or FA) staining method for diagnosis of HSV infection. HSV encephalitis and/or disseminated infection in marmosets were established by intracerebral, intramuscular, or intravenous inoculation of the virus. Brain tissues, liver, spleen, kidney, adrenal gland, lymph node, and lung were harvested and prepared for the virus isolation procedure in tissue culture and for direct FA staining. Data from six marmosets infected with HSV type 1 and two infected with type 2 indicated that the virus isolation method was more sensitive and reliable than the FA staining technique. False-negative results by FA staining were found in two situations: (1) presence of focal lesions that were missed by the frozen sections, and (2) presence of low concentrations of virus in tissue (is less than or equal to 3.5 log10 50% tissue culture infective doses/g). FA staining provides a rapid method for detection of viral antigens, but isolation of virus in tissue culture is required for a conclusive diagnosis of active infection.

Interaction of adenine arabinoside and host defense factors in experimental infections due to Herpesvirus hominis.

The role of host immune functions in relation to the antiviral effects of adenine arabinoside (ara-A) and/or humoral antibodies in Herpesvirus hominis infection was studied in four different mouse models (newborn Swiss mice, three-week-old Swiss mice, athymic nude [nu/nu] mice, and phenotypically normal [nu/+] littermates of nude mice). Although the overall beneficial effects afforded by the administration of ara-A and/or humoral antibodies were similar, the degree of protection varied among the four host systems. The data indicate that host defense factors play an important role in modulating the effect of humoral antibodies and/or an antiviral agent. Combined use of ara-A and humoral antibodies resulted in enhanced protection against H. hominis infection. Our data suggest that control of viral infection, particularly in compromised hosts, may require chemoimmunotherapy.

Synergistic effects of antiviral agents and humoral antibodies in experimental Herpesvirus hominis encephalitis.

Experimental Herpesvirus hominis encephalitis in 3-week-old Swiss mice was utilized to evaluate the antiviral effects of adenine arabinoside (ara-A), phosphonacetic acid (PAA), and humoral antibodies to H. hominis (HIG). Administration of ara-A, PAA, or HIG during the early phase of infection reduced the mortality rate of H. hominis encephalitis in mice. Combined administration of humoral antibodies with an antiviral agent (ara-A or PAA) resulted in an enhanced protection, accompanied by a decreased virus concentration in the brain tissues and a diminished tissue injury. The generality of this enhancing effect of humoral antibodies on the action of antiviral agents and its possible use in therapy of viral infections warrant further investigation.

Measurement of antibodies to Herpesvirus hominis by indirect immunofluorescent antibody method.

Antibodies to Herpesvirus hominis (HVH) were evaluated by indirect immunofluorescent antibody (FA) method. Frozen sections of HVH infected mouse brain provided antigens for FA staining. Our data indicate that indirect FA staining is a rapid, sensitive, and reproducible method for measurement of antibodies to HVH. Indirect FA method can be applied as an additional tool for the measurement of antibodies to HVH and can be applied for epidemiological survey of HVH infections.

Synergistic antiviral effects of adenine arabinoside and humoral antibodies in experimental encephalitis due to Herpesvirus hominis.

The antiviral effects of humoral antibodies and adenine arabinoside on encephalitis due to Herpesvirus hominis were studied in three-week-old mice. Exogenously administered antibodies to H. hominis, of rabbit or human origin, significantly reduced morbidity and mortality rates from H. hominis encephalitis if enough antibodies were given during the early phase of infection. Adenine arabinoside could also modulate the pathogenesis and reduce the mortality rate in mice with H. hominis encephalitis. Simultaneous administration of adenine arabinoside and human immune globulin resulted in an enhanced protection against H. hominis encephalitis. This increased protection was manifested by a significant reduction of mortality rate, a decrease in concentration of virus, and a lessening of histopathologic damage in the brain tissues. Mechanisms involved in the enhanced protective effects were not well defined. The use of adenine arabinoside plus human immune globulin did not completely suppress viral replication. Therefore, host recovery was probably mediated through (1) partial suppression of viral replication by adenine arabinoside, (2) neutralization of cell-free virus by antibodies, and (3) collaboration of antibodies with other host resistance factors (e.g., complement, leukocytes, nonimmune effector cells, etc.). Our data suggest that control of severe H. hominis infection may require the combined use of an antiviral agent and humoral factor and, perhaps, enhancement of host responses by other means.

Immunofluorescent staining for the measurement of antibodies to Herpesvirus hominis.

Frozen sections of Herpesvirus hominis-inoculated mouse brain provide excellent antigens for indirect immunofluorescent staining of antibodies to H. hominis in serum. Indirect immunofluorescent staining is a rapid, sensitive, and reproducible method for the measurement of antibodies to H. hominis. The method can be applied to the clinical and epidemiological studies of H. hominis infections.

Non-immunological precipitation of serum by sodium dodecyl sulfate in agar diffusion.

Marmoset serum or serum of other species of animal may react with sodium dodecyl sulfate and forms nonspecific precipitin lines in agar diffusion. The protein detergent complexes are not readily dialyzable. Therefore precipitin lines derived from studies that use sodium dodecyl sulfate-treated antigens in agar diffusion must be interpreted with caution.