Relationship of Pseudomonas syringae pv. tabaci races to the rhizosphere of Wisconsin-grown tobacco

Isolates of Pseudomonas syringae pv. tabaci, including 21 strains of the wildfire pathogen and 2 strains of the angular leafspot pathogen, were isolated from 143 rhizosphere and soil samples collected from 11 tobacco fields in Wisconsin. These pathogens were isolated by inoculating rhizosphere and soil washings into tobacco leaves and isolating the bacteria from wildfire or angular leafspot lesions that developed on the leaves. The wildfire isolates were from the rhizospheres of tobacco and Panicum capillare and from soil. While the majority of these were from wildfire-diseased fields, one isolate was from a field without disease symptoms; both angular leafspot isolates were from fields without angular leafspot symptoms. The majority of wildfire isolates were race 1, but three were race 0, and one was a new race. In three fields multiple races of wildfire were found. Both angular leafspot isolates were race 1. Two wildfire and one angular leafspot isolates were from fields where the cultivars were resistant to the races isolated.     

Infection rate of Babesia spp. sporokinetes in engorged Boophilus microplus from an area of enzootic stability in the State of Minas Gerais, Brazil

The infection rates of Babesia sporokinetes in engorged Boophilus microplus were evaluated during a 2-year period in a dairy farm located in an area of enzootic stability. Every 14 days engorged females were collected from calves and from adult animals. Ticks were incubated at 27 +/- 0.5 degree C and 80-90% relative humidity and Babesia infection rates were determined by microscopic examination of Giemsa-stained hemolymph smears. After 52 collections, 2105 ticks were obtained, from which 982 were collected from calves and 1123 from cows. The total Babesia infection rate was 10%, however the incidence was higher (p < 0.05) in ticks collected from calves (17.5%) than in those collected from cows (3.6%). Females collected from cows showed the highest infection rates in January, March, and August, and absence of infection in April and May. Ticks feeding on calves were infected throughout the experimental period. The infection rates of engorged females collected from naturally infected calves that were artificially infested with Babesia-free-larvae of B. microplus gradually decreased until the calves were four months old. No differences were observed among infection rates of ticks collected from calves maintained under natural conditions.     

Immunochemistry of Biliproteins

Biliproteins were extracted from representatives of the Cyanophyta, Rhodophyta, and Cryptophyta and purified. Both purified and crude biliproteins were used to stimulate rabbit antibody directed specifically against the biliproteins. The antigenic and immunogenic inter-relationships of these proteins were investigated by the Ouchterlony double diffusion technique. C-phycocyanins from all sources were found to be antigenically and immunogenically related and apparently also related to allophycocyanin but not to any of the phycoerythrins. Larger antigenic differences among phycoerythrins from different groups of algae were discovered. The role of aggregation of the individual biliproteins in their immunochemistry was characterized. Attempts were made to determine the phylogenetic significance of these results. The immunochemical aspects of the biliproteins were striking in that protein antigens from vastly different cell types were found to be closely related. This relationship may be interpreted as supporting the suggestion that Rhodophyta evolved from Cyanophyta or from some common ancestral stock.     

Nonsurgical recovery of degenerative ova from the uteri of mares

Degenerated ova were recovered with and without viable embryos 6 days after ovulation in 30 of 210 collections from 24 of 66 mares. All ova were approximately 150 mum in diameter, with an intact zona pellucida and at various stages of cytoplasmic degeneration. Most of the ova were collapsed, although some had an oval appearance. Most of the ova were from maiden 2-year-old mares. Thirty-four of the ova were recovered from the first or second collections. Two ova were recovered from the third collection from two mares. Two degenerative ova per collection were recovered from five collections; three of these collections also contained viable embryos. Degenerated ova were recovered from three mares twice; but not from consecutive collection attempts. Recovered ova were fixed in 2% glutaraldehyde-PBS for scanning electron microscopy. These data indicate that not all unfertilized ova remain permanently in the oviduct; many traverse it and enter the uterus. Furthermore, these data also suggest that when degenerative ova pass into the uterus they either degenerate further and (or) move into the vagina. This is supported by the fact that not all ova can be accounted for when the uterus and (or) the oviducts are washed.     

银杏内生菌的分离及其抑菌活性筛选

从健康的银杏（Ginkgo biloba）茎和叶片中分离内生菌,结果从银杏叶和茎上共分离到内生真菌20株,其中9株来自银杏茎部,11株来自银杏叶部;内生放线菌23株,其中15株来自于银杏茎部,8株来自于银杏叶部;内生细菌15株,其中8株来自于银杏茎部,7株来自于银杏叶部。以金黄色葡萄球菌（Staphylococcus aureus）、枯草芽胞杆菌（Bacillus subtilis）、大肠埃希菌（Escherichia coli）、黑曲霉（Aspergillus niger）、酿酒酵母（Saccharomyces cerevisiae）作为指示菌,采用双层平板法对内生菌进行抑菌活性筛选,结果表明：20株内生真菌中有12株出现了抑菌活性,有抑菌活性菌株的比例为60.0%;23株内生放线菌中,仅3株出现了抑菌活性,有抑菌活性菌株的比例为13.0%;15株内生细菌中,有4株出现了抑菌活性,有抑菌活性菌株的比例为26.7%。     

Recovery and analysis of formyltetrahydrofolate synthetase gene sequences from natural populations of acetogenic bacteria

Primers for PCR amplification of partial (1,102 of 1,680 bp) formyltetrahydrofolate synthetase (FTHFS) gene sequences were developed and tested. Partial FTHFS sequences were successfully amplified from DNA from pure cultures of known acetogens, from other FTHFS-producing organisms, from the roots of the smooth cordgrass, Spartina alterniflora, and from fresh horse manure. The amplimers recovered were cloned, their nucleotide sequences were determined, and their translated amino acid sequences were used to construct phylogenetic trees. We found that FTHFS sequences from homoacetogens formed a monophyletic cluster that did not contain sequences from nonhomoacetogens and that FTHFS sequences appear to be informative regarding major physiological features of FTHFS-producing organisms.     

Plasmid profiles as indicators of the source of contamination of Staphylococcus aureus endemic within poultry processing plants

A total of 530 strains of Staphylococcus aureus were isolated from the defeathering machinery of a chicken processing plant and from neck skin samples of carcasses at different stages of processing in two visits 4 weeks apart. Eleven different plasmid profiles were detected in the isolates, eight being common to both visits. The plasmid profiles of the strains forming the majority of the population on the freshly slaughtered birds were rarely present in the strains isolated from the pluckers (except at the entry to the first plucker) and were present in only a small proportion of the strains isolated from carcasses after plucking. However, the profiles from the strains isolated from the pluckers on both visits were different from those forming the majority of the population on the incoming birds but formed the major part of the carcass flora after plucking, suggesting that such strains were endemic. These strains were found as a small proportion of the isolates made from the incoming birds, suggesting that this was the route by which the endemic strains were introduced into the plant. Such endemic strains exhibited a clumping growth, even in liquid shake culture, which may have made it easier for them to become established on the pluckers and to resist cleaning and disinfection. This clumping phenotype was correlated with the presence of a 7.5-megadalton plasmid.     

Dna Ploidy Studies of Benign and Malignant Tumours: Comparison of Flow Cytometry and Image Analysis Techniques Using Two Types of Cytological Specimen

DNA ploidy studies were carried out on Feulgen stained smears and cytocentrifuge preparations from 35 malignant tumours and four benign neoplasms using the CAS image analyser. The smears were prepared from scrapings from fresh tumour tissue whereas the cytocentrifuge preparations were prepared from single nuclear suspensions from paraffin-embedded cell blocks from the same tumour. Histograms obtained by image analysis of the tumour scrapes were compared with those obtained on the cytocentrifuge preparations. Concordant results were obtained in four benign tumours (100%) and 32 malignant tumours (91%). The results obtained by image analysis were also compared with results obtained by flow cytometry of the tumour tissue. Discordant results were obtained for three malignant tumours. Possible reasons for the discrepancy include sampling error, tumour heterogeneity and selective loss of cell populations during processing.     

Plasmid profiles as indicators of the source of contamination of Staphylococcus aureus endemic within poultry processing plants.

A total of 530 strains of Staphylococcus aureus were isolated from the defeathering machinery of a chicken processing plant and from neck skin samples of carcasses at different stages of processing in two visits 4 weeks apart. Eleven different plasmid profiles were detected in the isolates, eight being common to both visits. The plasmid profiles of the strains forming the majority of the population on the freshly slaughtered birds were rarely present in the strains isolated from the pluckers (except at the entry to the first plucker) and were present in only a small proportion of the strains isolated from carcasses after plucking. However, the profiles from the strains isolated from the pluckers on both visits were different from those forming the majority of the population on the incoming birds but formed the major part of the carcass flora after plucking, suggesting that such strains were endemic. These strains were found as a small proportion of the isolates made from the incoming birds, suggesting that this was the route by which the endemic strains were introduced into the plant. Such endemic strains exhibited a clumping growth, even in liquid shake culture, which may have made it easier for them to become established on the pluckers and to resist cleaning and disinfection. This clumping phenotype was correlated with the presence of a 7.5-megadalton plasmid.     

Chronic effects of low pH on length and weight of Atlantic salmon,Salmo salar

Synopsis Measurements were made on Atlantic salmon from five sources in New England. Fish were reared at pH 7.0 and 5.2 from hatch to 199, 270 or 440 days. Length and weight were smaller in Atlantic salmon, Salmo salar, that were continuously exposed to low pH in the laboratory. Length and weight in neutral pH water varied among fish from the different sources. Fish from the Green Lake, Craig Brook, and Tunison sources were not significantly different in their lengths over time. Cortland and landlocked Atlantic salmon were not significantly different from one another but were significantly different from the other three sources. At pH 5.2, there were no significant differences in length between fish from any of the five sources. The Cortland salmon were significantly different from the other four sources in respect to their weight over time at neutral pH. At pH 5.2, there were no significant differences between any of the five sources.Cooperators are the U.S. Fish and Wildlife Service, the Maine Department of Inland Fisheries and Wildlife, the University of Maine, and the Wildlife Management Institute     

Tissue distribution and molecular characterization of chicken isolates of Toxoplasma gondii from Peru

The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii antibodies in sera of 50 free-range chickens (Gallus domesticus) from Peru was 26% on the basis of the modified agglutination test (MAT). Hearts, pectoral muscles, and brains of seropositive (MAT > or =1:5) chickens were bioassayed individually in mice. Tissues from the remaining 37 seronegative chickens were pooled and fed to 2 T. gondii-free cats. Feces of cats were examined for oocysts; they did not shed oocysts. Toxoplasma gondii was isolated from the hearts of 10 seropositive chickens but not from their brains and pectoral muscles. Genotyping of these isolates using the SAG2 locus indicated that 7 isolates were type I and 3 were type III. Six of the 7 type-I isolates were avirulent for mice, which was unusual because type-I isolates are considered virulent for mice. The T. gondii isolates were from chickens from different properties that were at least 200 m apart. Thus, each isolate is likely to be different. This is the first report of isolation of T. gondii from chickens from Peru.     

Use of pulsed-field gel electrophoresis to characterize the heterogeneity and clonality of salmonella isolates obtained from the carcasses and feces of swine at slaughter

Salmonella enterica isolates were recovered from swine at a collaborating processing plant over a 2-month period in the spring of 2000. In the present study, molecular subtyping by pulsed-field gel electrophoresis (PFGE) was performed on the 581 confirmed Salmonella isolates from the 84 Salmonella-positive samples obtained from the previous study. A total of 32 different PFGE pulsotypes were observed visually, and a BioNumerics software analysis clustered those pulsotypes into 12 PFGE groups. The B, F, and G groups predominated throughout the sampling period and were isolated from 39, 22, and 13% of the swine, respectively. In addition, multiple isolates were obtained from 67 of the 84 Salmonella-positive samples, and subtyping revealed multiple PFGE profiles in 35 of these 67 (62%) samples. Both carcass and fecal isolates of Salmonella were recovered from 13 swine, resulting in "matched" samples. Molecular typing of the 252 isolates recovered from the matched samples revealed that 7 (54%) of the 13 carcasses were contaminated with Salmonella pulsotypes that were not isolated from the feces of the same animal. Conversely, from 6 of the 13 (46%) matched animals, Salmonella clonal types were isolated from the feces that were not isolated from the carcass of the same animal. These data establish that each lot of swine introduces new contaminants into the plant environment and that swine feces from one animal can contaminate many carcasses. In addition, these results indicate that the examination of multiple Salmonella isolates from positive samples is necessary to determine the variety of potential contaminants of swine carcasses during slaughter and processing.     

The IsTaR 1 serodeme of Trypanosoma brucei: development of a new serodeme

An extensive serodeme of sequentially-isolated antigenic variants of African trypanosomes has been produced from both syringe-passaged and cyclically-transmitted Trypanosoma brucei of the IsTaR 1 clone derived from EATRO 164. The majority of the antigenic variants were isolated from chronically-infected deer mice (Peromyscus leucopus). The pattern of parasitemias during the course of infections initiated with syringe-passaged trypanosomes differed from those initiated with cyclically-transmitted trypanosomes. Trypanosome populations from syringe-passaged (192) and cyclically-transmitted (31) clones were each amplified by growth in lethally-irradiated mice and cryopreserved for retrospective analysis. Five clones derived from a single deer mouse during the first 44 days of infection, and 2 clones derived from an acutely-infected rat were established from these amplified populations. Homogeneous populations were grown in lethally-irradiated rats and mice for antigenic analysis purification of variant-specific glycoprotein. Six of the 7 clones were distinct variants by immunological criteria using antisera derived from whole cells or purified surface glycoproteins. Two clones, one derived from the acutely-infected rat, and the other from the first parasitemia in a chronic infection that was initiated with the former clone, were immunologically identical. Production of these clones established a well-defined serodeme that will allow detailed analysis of antigenic variation.     

Comparison of meat composition from offspring of cloned and conventionally produced boars

This study compares the meat composition of the offspring from boars produced by somatic cell nuclear transfer (n=4) to that of the offspring from conventionally produced boars (n=3). In total, 89 commercial gilts were artificially inseminated and 61 progressed to term and farrowed. All of the resulting piglets were housed and raised identically under standard commercial settings and slaughtered upon reaching market weight. Loin samples were taken from each slaughtered animal and shipped offsite for meat composition analysis. In total, loin samples from 404 animals (242 from offspring of clones and 162 from controls) were analyzed for 58 different parameters generating 14,036 and 9396 data points from offspring of clones and the controls, respectively. Values for controls were used to establish a range for each parameter. Ten percent was then added to the maximum and subtracted from the minimum of the control range, and all results within this range were considered clinically irrelevant. Of the 14,036 data points from the offspring of clones, only three points were found outside the clinically irrelevant range, two of which were within the range established by the USDA National Nutrient Database for Standard Reference, Release 18, 2005; website: (www.nal.usda.gov/fnic/foodcomp/search/). The only outlier was the presence of Eicosadienoic acid (C20:2) in one sample which is typically present in minute quantities in pork; no reference data were found regarding this fatty acid in the USDA National Nutrient Database. In conclusion, these data indicated that meat from the offspring of clones was not chemically different than meat from controls and therefore supported the case for the safety of meat from the offspring of clones.     

The protein-synthesizing activity of ribosomes isolated from the mammary gland of lactating and pregnant guinea pigs

1. Polyribosome preparations were made from the deoxycholate-treated post-nuclear fractions obtained by the disruption of mammary glands from lactating and pregnant guinea pigs. 2. A high proportion of large polyribosomes was obtained from the glands of lactating animals whereas mainly small polyribosomes were obtained from the glands of pregnant animals. The isolated preparations incorporated [(14)C]phenylalanine into protein. The polyribosomes from the glands of pregnant animals were less active than those from the glands of lactating animals but the activity of the former was stimulated more by poly(U) than was the latter. 3. The ribosomes from mammary gland could be dissociated into subunits after incubation, under conditions necessary for protein synthesis, in the presence of puromycin. The subunits could be recombined to give a preparation that actively polymerized [(14)C]phenylalanine in the presence of poly(U). The subunits from guinea-pig mammary gland could be combined with subunits from liver of either guinea pig or rat. Hybrid ribosomes were also formed from subunits derived from glands of pregnant and lactating animals. The hybrids were as active as were the ribosomes formed by reassociation of subunits from the same tissue, suggesting that in this respect the ribosomes from pregnant animals were not defective. 4. Polyribosomes from mammary glands of lactating animals when incubated with cell sap from the same source were tested for their ability to synthesize alpha-lactalbumin. The polyribosomes were incubated in the presence of [(3)H]leucine and alpha-lactalbumin was isolated from the supernatant. The protein was finally treated with cyanogen bromide and the C-terminal and N-terminal fragments were separated and their radioactivity was determined. Both fragments were radioactive consistent with the synthesis of alpha-lactalbumin. 5. The results are discussed in relation to protein synthesis in the mammary gland after parturition.     

Agricultural animals as a source of yersiniosis

The role of agricultural animals as the sources of infection was studied. 8 Yersinia strains were isolated from 83 samples taken from cattle. Yersinia were isolated from feces, udder washings and milk. In the examination of 63 samples obtained from sheep the infective agent was isolated from feces in 6 cases. 6 Yersinia strains were isolated from 92 fecal samples taken from pigs. Y. enterocolitica were isolated from sick animals. The isolated strains were classified with serovars 03, 058, 08 and 09. In the foci of animal infection thus revealed antibodies to various Yersinia strains were detected in the blood sera of the animal-tending personnel, which indicates the professional character of the spread of this infection among humans. The infection is probably transferred by the contact and alimentary routes.     

Agars of Gelidiella acerosa of west and southeast coasts of India

Seventeen agar samples were extracted from Gelidiella acerosa (Forsskal) Feldmann and Hamel (Rhodophyta, Gelidiales) specimens collected from nine different sites on the Indian coast-five from southeast coast and four from the west coast. The agar samples were analysed. The stability characteristics of the gels of selected agar samples were studied by rheometry under applied stress conditions, i.e. variation of the storage (G') and loss moduli (G') were studied under varying frequency and duration (time) of the stress applied. Yield, apparent and dynamic viscosities, gelling and melting temperatures, 3,6-anhydrogalactose (3,6-AG), sulphate contents and TGA (Thermogravimetric Analysis) measurements of the products were done. It was observed that the best quality agar was produced by G. acerosa occurring in the Gulf of Mannar region in the southeast coast. The gel strengths and the viscosities of agars extracted from Gelidiella acerosa occurring in the Gulf of Mannar ranged from 500 to 700gcm(-2) and 33 to 45cP for 2001 collections and for 2002 collections the corresponding values were 450 to 845gcm(-2) and 55 to 67cP respectively. On the other hand, for the agar samples extracted from the west coast of India, the gel strength and viscosities values ranged from 225 to 400gcm(-2) and from 15 to 30cP, respectively. The agars obtained from G. acerosa collected from southeast coast have been found to be suitable for bacterial culture and molecular biology. This is the first report of superior quality of agar from the Indian agarophytes.     

Masquerades of malignancy: a review of 4,241 aspirates from the breast

A total of 4,241 aspirates from the breast were obtained by fine needle aspiration biopsy. Of the 3,809 benign lesions, 61 (1.6%) were interpreted as possibly malignant. In all, excisional biopsy, not mastectomy, was recommended as the next procedure. More than 50% of these misdiagnoses were from aspirates of fibrocystic disease, 15% were from fibroadenomas, and the remainder were from gynecomastia, solitary papillomas, periareolar hyperplasia, pregnancy hyperplasia and granulation tissue. Most errors were based on specimens that were insufficiently cellular or whose poorly preserved cells lacked the majority of the criteria of malignancy.     

Some differences in the parasitic fauna of three samples of plaice (Pleuronectesplatessa L.) from the southern North Sea

Plaice ( Pleuronectesplatessa L.) from three spawning areas in the southern North Sea were examined for six species of metazoan parasite. Differences of both incidence and level of infestation with particular parasite species were found in fish from the three areas. Neither the incidence nor the level of infestation was associated with the length of fish in the samples except in the case of the larger male fish from Flamborough, which tended to contain more larval nematodes (Anisakidae). All fish contained the intestinal nematode Cucullanus heterochrous , although fewer were found in fish from Flamborough. Southern Bight fish were more likely to contain Capillaria wickinsi than were fish from Flamborough or the German Bight. Flamborough fish were more likely to contain Anisakidae larvae than were fish from the other two areas. Fish from the three areas were similarly infested with Zoogonoides viviparus. Male fish from Flamborough were less likely to be infested with Lepeophtheirus pectoralis than male fish from the German Bight.     

Recovery and Analysis of Formyltetrahydrofolate Synthetase Gene Sequences from Natural Populations of Acetogenic Bacteria

Primers for PCR amplification of partial (1,102 of 1,680 bp) formyltetrahydrofolate synthetase (FTHFS) gene sequences were developed and tested. Partial FTHFS sequences were successfully amplified from DNA from pure cultures of known acetogens, from other FTHFS-producing organisms, from the roots of the smooth cordgrass, Spartina alterniflora, and from fresh horse manure. The amplimers recovered were cloned, their nucleotide sequences were determined, and their translated amino acid sequences were used to construct phylogenetic trees. We found that FTHFS sequences from homoacetogens formed a monophyletic cluster that did not contain sequences from nonhomoacetogens and that FTHFS sequences appear to be informative regarding major physiological features of FTHFS-producing organisms.