Survey of zearalenone and type-B trichothecene mycotoxins in swine feed in the USA

AbstractAvian pneumovirus (APV) primarily causes an upper respiratory disease recognized as turkey rhinotracheitis (TRT) or swollen head syndrome (SHS) in chickens. The virus was first isolated in South Africa during the early 1970s and has subsequently been reported in Europe, Asia and South America. In February 1997, a serologically distinct APV isolate was officially reported in the USA following an outbreak of TRT during the previous year. This was the first report of these virus types in the USA; they were previously considered exotic to the USA and Canada. The predicted matrix (M) proteins of European APV type A and B isolates share 89% identity in their amino acid sequence. However, the predicted M protein of APV/CO is only 78%similar to the APV type A and 77% similar to the APV type B protein sequence. The predicted amino acid sequence of the US APV isolate's fusion (F) protein has 72% sequence identity to the F protein of APV type A and 71%sequence identity to the F protein of type B. This compares with the 83%sequence identity between the predicted amino acid sequences of the F proteins of APV types A and B. The lack of sequence heterogeneity among the US APV isolates over 2 years suggests that these viruses have maintained a relatively stable population since the first outbreak of TRT. Phylogenetic analysis of the M and F proteins, together with the serological uniqueness of the US APV isolates, supports their classification as a new APV, designated type C.

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Variation in the Bemisia tabaci s. 1. species complex (Hemiptera: Aleyrodidae) and its natural enemies leading to successful biological control of Bemisia biotype B in the USA

Bulletin of Entomological Research ◽

10.1017/s0007485300000444 ◽

2000 ◽

Vol 90 (4) ◽

pp. 317-327 ◽

Cited By ~ 51

Author(s):

A.A. Kirk ◽

L.A. Lacey ◽

J.K. Brown ◽

M.A. Ciomperlik ◽

J.A. Goolsby ◽

...

Keyword(s):

Biological Control ◽

Bemisia Tabaci ◽

Species Complex ◽

Release Site ◽

Molecular Classification ◽

Type B ◽

Encarsia Formosa ◽

Eretmocerus Mundus ◽

The Usa ◽

Biotype B

AbstractParasitoids of the Bemisia tabaci (Gennadius) species complex collected in Spain and Thailand were evaluated as biological control agents of B. tabacibiotype B in cole crops in Texas, USA. Parasitoids were identified by morphological and RAPD–PCR analyses. The most abundant parasitoid from Spain was Eretmocerus mundus Mercet with apparent field parasitism of 39–44%. In Thailand, Encarsia formosa Gahan, E. transvena Timberlake, E. adrianaeLopez-Avila, Eretmocerus sp. 1 and sp. 2 emerged, with apparent field parasitism of 1–65%. Identification and molecular classification of B. tabaciassociated with parasitoid collections and in the release site in Texas were accomplished using morphological traits and nucleotide sequence comparison of the mitochondrial cytochrome oxidase I gene (COI) (700–720 bp). Collections of B. tabacifrom Thailand grouped separately from B types from Arizona and Florida and the target B type from Texas, USA, a cluster from India, and other New World B. tabaci. The Spanish B. tabaci host of E. mundus which was laboratory and field-tested to achieve biological control of the B type was most closely related to non-B type B. tabaci populations from Spain and Sudan, the latter which formed a second group within the larger clade that also contained the B type cluster. Laboratory tests indicated that E. mundus from Spain parasitized more B. tabaci type B than did Eretmocerus spp. native to Texas and other exotic parasitoids evaluated. Eretmocerus mundus from Spain also successfully parasitized B. tabaci type B when field-released in a 0.94 million ha test area in Texas, and has significantly enhanced control of B. tabaci type B in California, USA. In contrast, parasitoids from Thailand failed to establish in the field in Texas, collectively suggesting a positive correlation between the centres of diversity of compatible parasitoid–host complexes.

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Morphological and molecular characterisation and diagnostics of some species of Scutellonema Andrássy, 1958 (Tylenchida: Hoplolaimidae) with a molecular phylogeny of the genus

Nematology ◽

10.1163/15685411-00002714 ◽

2013 ◽

Vol 15 (6) ◽

pp. 719-745 ◽

Cited By ~ 12

Author(s):

Esther van den Berg ◽

Louwrens R. Tiedt ◽

Esther van den Berg ◽

Louwrens R. Tiedt ◽

...

Keyword(s):

South Africa ◽

Type A ◽

28S Rrna ◽

Molecular Characterisation ◽

Type B ◽

Gene Sequences ◽

Electron Microscopic ◽

Coi Mtdna ◽

The Usa ◽

Its Rrna

Scutellonema spp. are widely distributed across tropical and subtropical regions of the world and are associated with numerous agricultural and horticultural crops. Identification of many Scutellonema species is not always reliable, in part because many species share very similar diagnostic characters. In this study, we provide morphological and molecular characterisation of S. brachyurus from the USA and South Africa, S. bradys from Nigeria and three unidentified species from California, USA, New Zealand and Burkina Faso. Morphological descriptions, measurements, light and scanning electron microscopic photos and drawings are given for S. brachyurus. Females of S. brachyurus from the USA (type A) and South Africa (type B) showed a significant variation in the number of sectors and blocks on the lip annuli, ranging from about 4-12 and from 8-20, respectively. Molecular analysis using the D2-D3 of 28S rRNA, ITS rRNA and the COI mtDNA gene sequences revealed two distinct genotypes within S. brachyurus samples: type A (samples from USA, Italy, Korea, Taiwan) and type B (South Africa). Multivariate analyses determined that S. brachyurus from the USA and Taiwan (type A) differed from that from South Africa (type B) mainly in body, tail and DGO lengths, and ratios b′, c′, c and V. Phylogenetic relationships within Scutellonema are given as inferred from the analyses of the D2-D3 of 28S rRNA, ITS rRNA and the COI mtDNA gene sequences. PCR-RFLP diagnostic profiles and PCR with species-specific primers are developed for the studied Scutellonema species.

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Biological and Morphological Studies on Low-Leukemia-Strain Mice with Hodgkin's-Like Neoplasia Induced by Serial Cell-Free Transmission of Leukemic Organs of SJL/J Strain Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100792 ◽

1968 ◽

Vol 26 ◽

pp. 210-211

Author(s):

S. Fujinaga ◽

K. Maruyama ◽

C.W. Williams ◽

K. Sekhri ◽

L. Dmochowski

Keyword(s):

Tissue Culture ◽

Type A ◽

Reticulum Cell ◽

Type B ◽

Viral Origin ◽

Serial Transfer ◽

Strain Mouse ◽

Morphological Studies ◽

Cell Neoplasm ◽

Free Material

Yumoto and Dmochowski (Cancer Res.27, 2098 (1967)) reported the presence of mature and immature type C leukemia virus particles in leukemic organs and tissues such as lymph nodes, spleen, thymus, liver, and kidneys of SJL/J strain mice with Hodgki's-like disease or reticulum cell neoplasm (type B). In an attempt to ascertain the possibility that this neoplasia may be of viral origin, experiments with induction and transmission of this neoplasm were carried out using cell-free extracts of leukemic organs from an SJL/J strain mouse with spontaneous disease.It has been possible to induce the disease in low-leukemia BALB/c and C3HZB strain mice and serially transfer the neoplasia by cell-free extracts of leukemic organs of these mice. Histological examination revealed the neoplasia to be of either reticulum cell-type A or type B. Serial transfer is now in its fifth passage. In addition leukemic spleen from another SJL/J strain mouse with spontaneous reticulum cell neoplasm (type A) was set up in tissue culture and is now in its 141st serial passage in vitro. Preliminary results indicate that cell-free material of 39th tissue culture passage can reproduce neoplasia in BALB/c mice.

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Cryo-electron microscopy of two-dimensional crystals of reduced type B botulinum neurotoxin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123052 ◽

1992 ◽

Vol 50 (1) ◽

pp. 530-531

Author(s):

P. F. Flicker ◽

V.S. Kulkarni ◽

J. P. Robinson ◽

G. Stubbs ◽

B. R. DasGupta

Keyword(s):

Disulfide Bonds ◽

Clostridium Botulinum ◽

Structural Changes ◽

Two Dimensional ◽

Type B ◽

Single Chain ◽

Muscle Paralysis ◽

Cryo Electron Microscopy ◽

Disulfide Linkages ◽

Intracellular Action

Botulinum toxin is a potent neurotoxin produced by Clostridium botulinum. The toxin inhibits release of neurotransmitter, causing muscle paralysis. There are several serotypes, A to G, all of molecular weight about 150,000. The protein exists as a single chain or or as two chains, with two disulfide linkages. In a recent investigation on intracellular action of neurotoxins it was reported that type B neurotoxin can inhibit the release of Ca++-activated [3H] norepinephrine only if the disulfide bonds are reduced. In order to investigate possible structural changes in the toxin upon reduction of the disulfide bonds, we have prepared two-dimensional crystals of reduced type B neurotoxin. These two-dimensional crystals will be compared with those of the native (unreduced) type B toxin.

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