Bacterial dehalogenation of halogenated alkanes and fatty acids.

Sewage samples dehalogenated 1,9-dichloronane, 1-chloroheptane, and 6-bromohexanoate, but an organism able to use 1,9-dichlorononane as the sole carbon source could not be isolated from these samples. Resting cells of Pseudomonas sp. grown on n-undecane, but not cells grown on glycerol, dehalogenated 1,9-dichlorononane in the presence of chloramphenicol. Resting cells of five other n-undecane-utilizing bacteria cleaved the halogen from dichlorononane and 6-bromohexanoate, and four dehalogenated 1-chloroheptane; however, none of these organisms used 1,9-dichlorononane for growth. By contrast, four benzoate-utilizing bacteria removed bromine from 6-bromohexanoate but had little or no activity on the chlorinated hydrocarbons. Incubation of sewage with 1,9-dichlorononane increased its subsequent capacity to dehalogenate 1,9-dichlorononane and 6-bromohexanoate but not 1-chloroheptane. A soil isolate could dehalogenate several dichloralkanes, three halogenated heptanes, and halogen-containing fatty acids. An enzyme preparation from this bacterium released chloride from 1,9-dichlorononane.     

Bovine Adenovirus

Two adenovirus strains were isolated in calf testicle cell cultures from blood specimens of cattle in Japan. This is the first isolation of bovine adenovirus reported in Japan. The isolates were antigenically similar to each other and distinct from the hitherto described serotypes 1, 2 and 3 of bovine adenovirus. Unfortunately, bovine adenovirus types 4 and 5 were not available for comparison, and hence, until the matter is settled, the virus will be called “Bovine adenovirus type Nagano”. Nagano virus was identified as adenovirus on the bases of the inhibitory effect of 5-iodo-2′-deoxyuridine on virus replication, ether-resistance, effect of temperature and pH on infectivity, and fine structure of the virus particle. The virus grew and formed intranuclear inclusion bodies, a characteristic of adenovirus, in bovine testicle cells but not in bovine kidney cells. The virus agglutinated rat erythrocytes very poorly, but not sheep, goat, cattle, horse, guinea pig, hamster, chicken, and mouse cells. The virus produced adenovirus group-specific antigen in cell cultures. Sero-negative calves were readily infected with the virus by the intravenous, subcutaneous, oral or intranasal routes of inoculation. The infected animals produced antibodies and showed a mild clinical reaction comprised of rhinorrhea, diarrhea and a degree of pyrexia; low-titered viremia of short duration and leukopenia were also observed. A serologic survey indicated wide-spread dissemination of the virus among Japanese cattle, but further studies are needed to determine the etiologic significance of the virus in the natural disease in cattle.     

Some Factors Affecting on Dry Weight,Organic Weight and Concentrations of Carbon and Nitrogen in Freshly Prepared and in Preserved Zooplankton

Effects of rinsing and preservation on dry weight, organic weight, and chemical composition were determined on the chaetognath Sagitta nagae and the copepods Calanus sinicus, Pleuromamma xiphias and Acartia tonsa. Samples rinsed with distilled water were always lighter than comparable samples rinsed with seawater, showing apparent decrease in the organic matter and chemical contents (as total carbon and nitrogen) by weight; these losses increased with increasing volume of the rinse water. The volume of distilled water used for rinsing should be less than 0.3 ml per 1 mg dry weight of sample in order to avoid the significant loss of body substances. Isotonic ammonium formate rinse often resulted in the widest range of variation and on an average the organic weight and chemical contents were slightly lower than those of fresh samples rinsed with filtered seawater. Freeze-drying samples resulted in dry and organic weights as well as chemical compositions that were somewhat greater than oven-dried samples. The organic matter and chemical contents by weight decreased significantly within 2.5 days of being placed in Borax-buffered formaldehyde-sea water solution. Loss of organic weight from fresh samples exceeded 20% after one week of the preservation. Hexamine-buffered formaldehyde solution showed a result which was different from the Borax-buffered solution.     

Bovine Diarrhea Virus

Virus strain No. 12, one of the new isolates from Japanese cattle described previously, was studied for its physicochemical properties. The new isolate was shown to be very small in size by centrifugation and filtration, being filtrable through Millipore filters of 50 mμ pore size. It appears to be an RNA virus as its replication was not inhibited by 5-iodo-2′-deoxyuridine. The virus was readily inactivated by ether and deoxycholate, and partially by trypsin; was labile at pH 3, not stabilized by 1 m MgCl₂ at 50 C, was inactivated by ultraviolet, and withstood repeated freeze-thawing. Further it was readily inactivated at 56 C but more slowly at 37 C, and was stable at lower temperatures. These findings support the identification of the isolated virus as the bovine diarrhea (BD) virus. The properties of BD virus, i.e. size, type of nucleic acid, ether, chloroform and deoxycholate sensitivities, and acid lability, appear to be similar to those of arboviruses. The trypsin sensitivity of BD virus is similar to the B group of arboviruses, which, unlike the A group, sensitive to trypsin. For the classification of BD virus as well as hog cholera virus, which is closely related, further elucidation of properties, fine structure of the virion, etc., is needed.     

Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies

BackgroundAn estimated 75% or more of the human rabies cases in Africa occur in rural settings, which underscores the importance of rabies control in these areas. Understanding dog demographics can help design strategies for rabies control and plan and conduct canine mass vaccination campaigns effectively in African countries.Methodology/Principal findingsA cross-sectional survey was conducted to investigate domestic dog demographics in Kalambabakali, in the rural Mazabuka District of Zambia. The population of ownerless dogs and the total achievable vaccination coverage among the total dog population was estimated using the capture-recapture-based Bayesian model by conducting a canine mass vaccination campaign. This study revealed that 29% of the domestic dog population was under one year old, and 57.7% of those were under three months old and thus were not eligible for the canine rabies vaccination in Zambia. The population growth was estimated at 15% per annum based on the cross-sectional household survey. The population of ownerless dogs was estimated to be small, with an ownerless-to-owned-dog ratio of 0.01–0.06 in the target zones. The achieved overall vaccination coverage from the first mass vaccination was estimated 19.8–51.6%. This low coverage was principally attributed to the owners’ lack of information, unavailability, and dog-handling difficulties. The follow-up mass vaccination campaign achieved an overall coverage of 54.8–76.2%.Conclusions/SignificanceThis paper indicates the potential for controlling canine rabies through mass vaccination in rural Zambia. Rabies education and responsible dog ownership are required to achieve high and sustainable vaccination coverage. Our findings also propose including puppies below three months old in the target population for rabies vaccination and emphasize that securing an annual enforcement of canine mass vaccination that reaches 70% coverage in the dog population is necessary to maintain protective herd immunity.     

Semi-automated single-molecule microscopy screening of fast-dissociating specific antibodies directly from hybridoma cultures

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Isolation,Identification and Substrate Assimilation Specificity of Some Aromatic Hydrocarbon Utilizing Bacteria

As a result of screening isoalkyl or isoalkenyl substituted aromatic hydrocarbon assimilating microorganisms, 19 strains of isopropylbenzene assimilating bacteria were isolated. Thirteen of these strains were found to grow on α-methylstyrene and all 4 strains tested were also found to grow on isobutylbenzene.

Among them, 2 strains (S107B1 and S182BI) were selected for further study and were identified as Ps. convexa and Ps. ovalis, respectively.

Furthermore, some examined aromatic hydrocarbon utilizing bacteria were classified into two groups by differences in substrate assimilation specificity.