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Japanese medaka, (Oryzias latipes), small, freshwater, tropical cyprinodonts, are principally used for toxicologic and carcinogenicity assays, but are finding more applications in developmental genetic and biological research. An increase in mortality began in brood stock of adult medaka that had been shipped and housed separately by sex. Initially, mortality averaged one fish daily and began in females two weeks after they were received. Cohabitation began eight weeks after arrival. After four to six weeks of cohabitation in different spawning aquaria, mortality was observed in males. Clinical signs of disease included loss of scale luster and color, with subsequent blanching of dorsal flank musculature, small raised nodules on various external surfaces, emaciation, fraying of fin tips, and equilibrium disturbances. Histologic examination of affected adults revealed multi-organ granulomatous inflammation with intracellular acid-fast bacilli. Specimens from 46 juvenile medaka that were spawned from affected adults, were submitted for culture and histologic evaluation. Of 18 fish, two had lesions similar to those of adults. The organism isolated from the remaining fish was identified as Mycobacterium fortuitum. Due to atypical rapid progression of disease, spread of M. fortuitum to progeny, and poor prognosis, the entire colony was euthanized.

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OBJECTIVE: The following studies were performed in order to evaluate the stability of paraspinal tissue compliance measurements. Tissue compliance is a measure of the consistency or firmness of soft tissue and is determined by a hand-held tissue compliance meter. DESIGN: Descriptive and blinded time course intervention measurements. SETTING: All measurements were performed on subjects placed in the prone position on flat tables in a laboratory setting. PARTICIPANTS: Forty asymptomatic volunteer subjects. INTERVENTION: Tissue compliance measurements of the T6 and L3 paraspinal regions. MAIN OUTCOME MEASURE: Tissue compliance measurements recorded as millimeters of penetration of a metered probe. RESULTS: Data from this study indicate that paraspinal tissue compliance at the T6 and L3 regions does not change significantly over a 10-min interval, is not effected by the testing intervention and the number of abnormal left/right tissue compliance asymmetries is appropriate (5%) for a normal population of subjects. CONCLUSIONS: These findings tend to support the utility of tissue compliance as a possible tool for the evaluation of paraspinal soft tissue.

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Seeds of Phaseolus vulgaris L. ev. Nerina were hand-sown inside open-top chambers (OTCs) in which the plants were exposed to charcoal-filtered air (CF treatment), ambient air (NF), or ambient air with added 6, 12, 18, 25 or 30 nl 1-1 of ozone (NF6, NF12, NF18, NF25 and NF30 treatments, respectively). Exposure commenced as the crop emerged and continued on a daily basis until the end of the season. Ozone (O3 ) was added between 10.00 and 18.00 h GMT. The seasonal 7 h mean O3 concentrations ranged from 10 nl l-1 in the CF treatment to 50 nl l-1 in the NF30 treatment. The growth and yield of P. vulgaris ev. Nerina demonstrated two distinct responses to O3 depending upon concentration. At seasonal 7 h means of 20, 26 and 32 nl l-1 (NF, NF6 and NF12 treatments respectively), the yield increased relative to that of the CF treatment. The increase in yield peaked at 48% in the NF6 treatment (P < 0.05), and was associated with a 55 % increase in the maximum leaf number, longer retention of the canopy, and a 45 % increase in the number of pods present at the final harvest. In contrast, seasonal 7 h mean O3 concentrations of 38, 45 and 50 nl l-1 (NF18, NF25 and NF30 treatments) caused 26-42 % reductions in the yield of P. vulgaris. The leaves of such plants developed extensive symptoms of O3 injury and were prematurely abscised from the plants. The reductions in yield were due to a decrease in the numbers of seeds per pod and in the weights of individual seeds.

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In 1988, open-top chambers (OTCs) based on the Raleigh (USA) design were used to investigate the effect of ambient pollutants on field-sown Vicia faba cv, Ticol. This paper reports an aspect of this study in which the effect of the chamber itself on crop growth and development was investigated. Non-filtered chamber (NF OTC) microclimates were typically 0.8°C warmer, with 20% less radiation and reduced wind speeds compared with open-field sub-plots (AA treatments). These differences are sufficient to induce alterations in the growth and development of V. faba. Plant development progressed more quickly inside the chambers in response to the faster accumulation of thermal time. Chamber-grown V. faba were up to 20 cm taller and had fewer branches (0.7 compared with 1.2 per plant) than plants grown in the AA treatments. Larger leaf areas developed on the NF plants, and there were fewer stomata per unit leaf area in this treatment (34 compared with 42 mm-2 , P= 0.01). Enclosure within an OTC did not alter the number of flowers per plant or the number of flowers which formed pods. However, at harvest, chamber-grown plants had a 13% higher yield than the plants grown in open-field plots. These differences in growth are described in relation to the microclimate differences between AA and NF treatments.

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The purpose of this study was to evaluate pain scores and plasma beta-endorphin levels following a single spinal adjustive manipulation in subjects with acute low back pain. Eighteen subjects were randomly assigned to either a control group, which received no treatment; a sham group, which received only light physical contact (touch); or an experimental group, which received an adjustive manipulation at a specific lumbar segment. Following a standard protocol, all subjects were administered visual analog pain scales and venous blood was drawn 5 min prior to, 5 min after, and 30 min after intervention. Analysis of the pain scores indicated that there was a slight, but significant, reduction of pain in the experimental group, but no similar reduction in the control or sham groups. Furthermore, this reduction of pain in the experimental group was not accompanied any significant change in the plasma beta-endorphin concentration.

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Six (3 control and 3 explanted) bioprostheses were examined histologically after embedding the complete valve in "plastic" and sectioning across the valve at 90 degree to the horizontal plane, and then horizontally across a stent post, with a low speed saw. The prostheses, porcine or pericardial, had been in place 52 to 121 months. In addition to cusp changes of degeneration and calcification that have been previously reported, the authors found extensive pannus deposition on the cloth covering the inflow surface of the prostheses, with some extension onto the biologic components; evidence of insudation of tissue fluid and ingrowth of fibroblasts; deposition of collagen; and infiltration of mononuclear cells in the interstices and interfaces. Non-biologic components showed changes which may have affected prosthesis function. The synthetic material covering the metal/plastic frame showed interstitial mononuclear cells. Two of the three explanted valves showed changes in the polymeric plastic, and one in the metal components, including accentuated notching along the surfaces when compared to unimplanted prostheses. A larger number of prostheses must be examined before definite conclusions can be drawn.

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The effect of Rosette Inhibitory Factor (RIF) on cyclic AMP generation by peripheral blood mononuclear cells (PBMC) and lymphocyte subpopulations (OKT4+ or helper T cells, OKT8+ or suppressor T cells, B lymphocytes) was analyzed. The results were compared to those observed with isoproterenol, an agent which is known to inhibit erythrocyte rosette (ER) formation and increase cyclic AMP levels in T cells. RIF elevated cyclic AMP levels in PBMC, an effect which was observed to be confined to helper T cells. Isoproterenol also elevated levels of cyclic AMP in PBMC but non-selectively augmented levels of the cyclic nucleotide in all lymphocyte subpopulations. Whereas isoproterenol increased cyclic AMP levels within 30 min, RIF did so after a lag period of 4 hr, a delay which is necessary for inhibition of ER formation. These studies reaffirm the selective effect of RIF on helper T cells. We conclude that inhibition of ER formation and possibly other immunoregulatory effects associated with RIF may be mediated via modulation of the adenyl cyclase-cyclic nucleotide network.

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The potential immunoregulatory effects of rosette inhibitory factor (RIF) were evaluated using lymphocyte subpopulations defined by monoclonal antibodies (OKT4, OKT8). Initial experiments indicated that RIF inhibits E-rosette formation by T cells that provide helper/inducer function (OKT4+). Subsequently, experiments were done to assess if RIF had an inhibitory effect on in vitro immunoglobulin and anti-HBs production. These studies used peripheral blood mononuclear cells from convalescent and hepatitis B-vaccinated donors. The results indicated that RIF-positive low-density lipoprotein, but not RIF-negative low-density lipoprotein, inhibits in vitro production of IgG and IgM by 60 to 70% and totally ablates anti-HBs synthesis. In order to determine if RIF directly affected the proliferative response of T4 lymphocytes, these cells were cultured in the presence of optimal mitogen concentrations and either RIF-positive or RIF-negative low-density lipoprotein. The experiments demonstrated that RIF-treated T4 cells are hyporesponsive to pokeweed mitogen and phytohemagglutinin when compared to T4 cells cultured in the absence of RIF. In contrast, B cell proliferation in response to soluble T helper factors was not affected by incubation with RIF. As the production of soluble helper factors by T4 cells was inhibited by exposure to RIF-positive but not RIF-negative low-density lipoprotein, we conclude that the suppressive effect of RIF on immunoglobulin and anti-HBs synthesis is due to inhibition of this specific helper T cell function.

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Thirty-eight patients with chronic active hepatitis type B received antiviral therapy. In one trial, 22 patients were randomized to either no treatment or treatment with a 28-day cycle of adenine arabinoside 5' monophosphate (ARA-AMP); in a second trial, 13 patients were randomized to no treatment or treatment with two 28-day cycles of ARA-AMP separated by a 4-wk rest interval; during a third trial, 11 individuals were treated with 8 wk of prednisone therapy followed by 28 days of ARA-AMP therapy. The response rate (73%) to the regimen with prednisone was significantly greater than that achieved in the first or second trial (0% and 15%, respectively). The data indicate that the combination of short-term prednisone and ARA-AMP therapy may offer more promise for successful treatment of chronic active hepatitis type B than does ARA-AMP alone. Synergism may possibly occur by the combined effects of immune rebound provided by corticosteroid withdrawal and the inhibition of viral proliferation by ARA-AMP.

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The prevalence of hepatitis B virus markers was studied among employees and clients at a nonresidential public school for the mentally handicapped and at a privately operated residential facility. In the residential institution, 73 (80%) of 91 clients and 15 (16%) of 92 workers had positive tests for hepatitis B virus markers. Twenty-three clients, including six carriers of hepatitis B surface antigen (subtype ayw), received their education their education at the public school. Only two students (4%) who did not live at the residential institution and one employee (2%) had positive tests for hepatitis B virus markers. One of these students had acute hepatitis B infection, with hepatitis B surface antigen subtype ayw; the subtyping suggested that he had acquired the infection from one of the six carriers from the residential institution. Testing for IgM antibody to hepatitis B core antigen in single serum samples facilitated the identification of acute and chronic hepatitis B infection in children and staff of both facilities. The results show hepatitis B can be transmitted in this setting, and vaccination may be warranted for susceptible students and staff.

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Abrupt increases of alanine transaminase were observed in 6 of 23 non-treated, male homosexuals with chronic hepatitis associated with hepatitis B virus. Before this occurrence, all subjects had hepatitis B e antigen (HBeAg) and elevated DNA polymerase activity. Within 3 months, HBeAg was nondetectable in 3 subjects and elevated DNA polymerase disappeared in 4. These serologic events were not always sustained, however. In 3 subjects, reactivation of hepatitis B virus infection occurred within the subsequent 6-month period. Serologic testing for cytomegalovirus, Epstein-Barr virus, delta agent, and hepatitis B surface antigen (HBsAg) subtype showed that episodes of clearance and reactivation were not explainable by secondary infection with these agents or infection with a different HBsAg subtype. Spontaneous clearance and reactivation of hepatitis B virus infection may commonly occur among male homosexuals with chronic type B hepatitis. These phenomena should be considered when evaluating the need for treatment or interpreting the results of investigations that use anti-viral therapy.

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The prevalence of hepatitis B virus (HBV) markers in 484 medical and 329 dental students was studied. Three students (0.9%) were hepatitis B surface antigen (HBsAg) reactive, and 46 students (5.7%) were reactive for antibody to HBsAg (anti-HBs). There was no difference in anti-HBs frequency between medical and dental students, and the prevalence of this marker was not associated with year in school. Of the 46 reactors, eight (17%) were nonreproducible and 38 (83%) were reproducibly reactive when the same samples were reanalyzed. Of note, all nonreproducible reactors exhibited anti-HBs sample-negative control (S/N) ratios of less than 10, and none were positive for antibody to hepatitis B core antigen (anti-HBc). Nineteen (50%) of the reproducible reactors had anti-HBs S/N ratios equal to or greater than 10, and only 15 (39%) were anti-HBc positive. In view of these observations, we do not recommend HBV screening in a vaccine program for health students. Due to the frequency with which low-level anti-HBs reactors without anti-HBc are found to be nonreproducibly positive, we are concerned by the potential overinterpretation of such results before the formulation of decisions about the need for vaccination.

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We report a case of Vibrio parahaemolyticus panophthalmitis which resulted from contamination of a wound with water from a pond in inland Georgia. The pond was on the property of an oil refinery which receives crude oil from southern Mississippi. Cultures of the pond water 5 years later did not yield V. parahaemolyticus, but did yield non-O1 V. cholerae and had 0.28% sodium chloride content. V. parahaemolyticus may have been introduced into the pond along with oil transported from the Gulf of Mexico, and growth of this halophilic species may have been supported by salt from spilled crude oil.

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