Identification of differentially expressed transcripts from maturing stem of sugarcane by in silico analysis of stem expressed sequence tags and gene expression profiling.

Sugarcane accumulates high concentrations of sucrose in the mature stem and a number of physiological processes on-going in maturing stem tissue both directly and indirectly allow this process. To identify transcripts that are associated with stem maturation, we compared patterns of gene expression in maturing and immature stem tissue by expression profiling and bioinformatic analysis of sets of stem ESTs. This study complements a previous study of gene expression associated directly with sugar metabolism in sugarcane.

Identification of a novel sugar transporter homologue strongly expressed in maturing stem vascular tissues of sugarcane by expressed sequence tag and microarray analysis.

The ability of sugarcane to accumulate sucrose provides an experimental system for the study of gene expression determining carbohydrate partitioning and metabolism. A sequence survey of 7242 ESTs derived from the sucrose-accumulating, maturing stem revealed that transcripts for carbohydrate metabolism gene sequences (CMGs) are relatively rare in this tissue. However, within the CMG group, putative sugar transporter ESTs form one of the most abundant classes observed.

Gill-associated nidovirus of Penaeus monodon prawns transcribes 3'-coterminal subgenomic mRNAs that do not possess 5'-leader sequences.

Sequence analysis of the approximately 20 kb 5'-terminal portion of the ssRNA genome of gill-associated virus (GAV) of Penaeus monodon prawns has previously established that it contains an ORF1a-1b replicase gene equivalent to those of the coronavirus and arterivirus members of the order Nidovirales. Sequence analysis of the remaining approximately 6.2 kb of the GAV genome downstream of ORF1a-1b to a 3'-poly(A) tail has identified two highly conserved intergenic sequences in which 29/32 nucleotides are conserved.

Gill-associated virus of Penaeus monodon prawns: an invertebrate virus with ORF1a and ORF1b genes related to arteri- and coronaviruses.

A 20089 nucleotide (nt) sequence was determined for the 5' end of the (+)-ssRNA genome of gill-associated virus (GAV), a yellow head-like virus infecting Penaeus monodon prawns. Clones were generated from a approximately 22 kb dsRNA purified from lymphoid organ total RNA of GAV-infected prawns. The region contains a single gene comprising two long overlapping open reading frames, ORF1a and ORF1b, of 4060 and 2646 amino acids, respectively.

Detection of Australian gill-associated virus (GAV) and lymphoid organ virus (LOV) of Penaeus monodon by RT-nested PCR.

A highly sensitive test based on reverse transcription followed by nested polymerase chain reaction (RT-nPCR) was developed to detect the Australian yellow-head-like viruses, gill-associated virus (GAV) and lymphoid organ virus (LOV) of Penaeus monodon. The RT-nPCR detected viral RNA in as little as 10 fg lymphoid organ total RNA isolated from GAV-infected P. monodon.

Yellow head virus from Thailand and gill-associated virus from Australia are closely related but distinct prawn viruses.

Corresponding genomic regions of isolates of yellow head virus (YHV) from Thailand and gill-associated virus (GAV) from Australia were compared by RT-PCR and sequence analysis. PCR primers designed from sequences in the GAV ORF1b polyprotein gene amplified the corresponding 577 nucleotide region of the YHV genome. Comparison of the amplified region indicated 85.

Vaccination against Babesia bovis: T cells from protected and unprotected animals show different cytokine profiles.

Vaccination of cattle against the haemoprotozoan parasite, Babesia bovis, with the recombinant antigen 11C5 resulted in 9 of 15 cattle being protected against challenge infection. The cellular immune responses of protected and unprotected cattle were compared in order to identify differences in response. No differences were observed in the pattern of change in various blood leukocyte populations throughout challenge infection.

Anaplasma marginale: effect of the treatment of cattle with an interferon gamma-neutralizing monoclonal antibody or the nitric oxide synthetase inhibitor aminoguanidine on the course of infection.

Cattle undergoing initial infection with the rickettsia Anaplasma marginale were treated with either a monoclonal antibody (MoAb) with neutralizing activity for bovine interferon gamma (IFN-gamma) or aminoguanidine (AG), a specific inhibitor of the inducible form of nitric oxide synthetase (iNOS). Plasma levels of MoAb and AG were measured over the time of administration. The course of A.

Increased resistance to Anaplasma marginale infection in cattle chronically infected with Theileria buffeli (syn. T. orientalis).

Calves chronically infected with the benign haemoprotozoan parasite Theileria buffeli (syn. T. orientalis) and T.

Anaplasma marginale: detection of carrier cattle by PCR-ELISA.

A highly sensitive and specific polymerase chain reaction (PCR) based assay for the detection of the minute levels of Anaplasma marginale present in the blood of long-term carrier cattle was developed. A simple lysis method was used to remove most of the haemoglobin from the blood to facilitate direct input of samples into the PCR reactions without prior purification of the DNA. PCR product was detected by enzyme-linked immunosorbent assay (ELISA) to simplify the processing of large numbers of samples.

Peripheral blood lymphocyte proliferative responses in cattle infected with or vaccinated against Anaplasma marginale.

An assay was developed for measurement of the peripheral blood lymphocyte proliferative response (PBLPR) in cattle infected with or immunised against Anaplasma marginale. PBLPR was not evident in all cattle that had recovered from A. marginale infection.

Control of bovine leukaemia virus transmission by selective culling of infected cattle on the basis of viral antigen expression in lymphocyte cultures.

The use of viral antigen expression in lymphocyte cultures to prioritize the culling of bovine leukaemia virus (BLV) infected cattle was evaluated as a means of controlling the spread of infection in heavily infected herds. Selective culling was implemented in five commercial dairy herds containing between 126 and 304 cattle with infection prevalences, based on serological testing using the agar gel immunodiffusion test, of 19.4%, 20.

A field evaluation of the polymerase chain reaction procedure for the detection of bovine leukaemia virus proviral DNA in cattle.

A polymerase chain reaction (PCR) procedure that detects proviral bovine leukaemia virus (BLV) in peripheral blood mononuclear cell DNA was evaluated. Blood samples from all animals (164) in a commercial dairy herd with a 30% prevalence of BLV infection, and from 194 animals from BLV free herds were tested. The absence of any positive PCR results in animals from BLV free herds confirmed the specificity of the assay.

Characterisation of a family of multi-copy genes encoding rhoptry protein homologues in Babesia bovis, Babesia ovis and Babesia canis.

A monoclonal antibody that had been raised against a protease-containing fraction of Babesia bovis, and shown to bind to a protein located in the rhoptries, was used to screen a B. bovis cDNA expression library. The sequence of the protein encoded by a positive clone was almost identical to the equivalent region of a previously described B.

T lymphocyte responses of sheep to bovine leukaemia virus infection.

Sheep were experimentally infected with bovine leukaemia virus (BLV) by inoculation of peripheral blood lymphocytes (PBL) from BLV infected sheep. Monoclonal antibodies were used to monitor changes in lymphocyte subpopulations in the first few weeks after inoculation. The polymerase chain reaction (PCR) detected BLV DNA in PBL of infected sheep 11-15 days after inoculation, that is, before antibodies to viral structural proteins were detected at 15-39 days post-inoculation.

Babesia bovis, Babesia bigemina, Babesia canis, Babesia microti and Babesia rodhaini: comparison of ribosomal RNA gene organization.

The three ribosomal DNA (rDNA) units have been cloned from an Australian isolate of Babesia bigemina. The organization of the units is very similar to that reported for a Mexican isolate of B. bigemina.

Infectivity of bovine leukaemia virus infected cattle: an ELISA for detecting antigens expressed in in vitro cultured lymphocytes.

A simple ELISA is described for quantifying expression of bovine leukaemia virus (BLV) antigens in short-term cultures of peripheral blood lymphocytes (PBL) isolated from infected cattle. The PBL-ELISA demonstrated that antigen expression levels in infected cattle could vary by more than 50-fold. Inoculation of sheep with dilutions of lymphocytes from two BLV-infected cattle, differentiated in the PBL-ELISA by 50 to 100-fold, suggested that antigen expression levels were correlated with infectivity.

Anaplasma marginale: failure of sera from immune cattle to confer protection in passive-transfer experiments.

High levels of immunity to Anaplasma marginale were induced in cattle either by vaccination using sonically disrupted A. marginale-infected erythrocytes or by repeated infection with different strains of the rickettsia. In both instances, high levels of anti-A.

Factors affecting the natural transmission of bovine leukaemia virus infection in Queensland dairy herds.

Natural transmission of bovine leukaemia virus (BLV) infection in south-eastern Queensland dairy herds was slow in 2 herds with a low to moderate (13 to 22%) prevalence of infection. Infection spread much more rapidly in a herd that had a higher prevalence (42%) when first tested. In a 13 month study of this herd, the cumulative incidence of infection was 24%.

Lymphocyte subpopulations in sheep with lymphosarcoma resulting from experimental infection with bovine leukaemia virus.

Sheep were experimentally infected with bovine leukaemia virus (BLV) and developed leukaemia and lymphosarcoma 30-88 weeks later. Ten sheep with lymphosarcoma were necropsied and lymphocyte subpopulations were evaluated in peripheral blood lymphocytes (PBL) and lymphocyte suspensions prepared from a range of lymph nodes, tumours and spleen. The leukaemic phase of BLV infection was characterized by an increase in the number of circulating B lymphocytes.

Lymphocyte subpopulations in sheep during the early stage of experimental infection with bovine leukaemia virus.

Sheep were experimentally infected with bovine leukaemia virus (BLV) by the inoculation of PBL from leukaemic sheep. Antibodies to viral structural proteins were detected at from 2 to 6 weeks after inoculation. At seroconversion, all sheep had a marked increase in the number of circulating lymphocytes, due essentially to an increase in the number of B cells.

Bovine leucosis virus contamination of a vaccine produced in vivo against bovine babesiosis and anaplasmosis.

Contamination of a batch of tick fever (babesiosis and anaplasmosis) vaccine with bovine leucosis virus (BLV) was detected when a herd, in the final stages of an enzootic bovine leucosis (EBL) accreditation program, developed a large number of seropositive cattle following use of tick fever vaccine. Investigations incriminated a single calf used to produce Anaplasma centrale vaccine from which 13,959 doses were distributed. The failure of this calf to give a positive agar gel immunodiffusion (AGID) test before use was not fully explained.

The toxicity of Castanospermum australe seeds for cattle.

Two calves given a mean of 16.1 g and 16.4 g ripe Castanospermum australe seeds/kg body weight daily for 13 and 16 days respectively developed haemorrhagic gastroenteritis.

BoLA antigens are associated with increased frequency of persistent lymphocytosis in bovine leukaemia virus infected cattle and with increased incidence of antibodies to bovine leukaemia virus.

The association between bovine major histocompatibility system (BoLA) type and persistent lymphocytosis in cattle with antibodies to bovine leukaemia virus was examined by comparing antigen frequencies in cattle with persistent lymphocytosis to controls matched for age, sex, breed and presence of antibodies to BLV. The cattle came from nine dairy herds in south-east Queensland, Australia; six herds were Australian Illawarra Shorthorn (AIS), two herds were Jersey and one herd was Friesian. Antigen W6 and Eu28R were more common in cattle with persistent lymphocytosis than in controls.