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In Argentina, classical vaccines are used to control infectious bursal disease virus (IBDV); however, outbreaks of IBDV are frequently observed. This could be due to failures in the vaccination programs or to the emergence of new strains, which would be able to break through the protection given by vaccines. Hence, genetic characterization of the viruses responsible for the outbreaks that occurred in recent years is crucial for the evaluation of the control programs and the understanding of the epidemiology and evolution of IBDV. In this study, we characterized 51 field samples collected in Argentina (previously identified as IBDV positive) through the analysis of previously identified apomorphic sequences. Phylogenetic analysis of regVP2 showed that 42 samples formed a unique cluster (Argentinean lineage), seven samples were typical classical strains (one of them was a vaccine strain), and two belonged to the very virulent lineage (vvIBDV). Interestingly, when the analysis was performed on the regVP1 sequences, the field samples segregated similarly to regVP2; thus, we observed no evidence of a reassortment event in the Argentinean samples. Amino acid sequence analysis of regVP2 showed a particular pattern of residues in the Argentinean lineage, particularly the presence of T272, P289 and F296, which had not been reported before as signature sequences for any IBDV phenotype. Notably, the residue S254, characteristic of the antigenic variant, was not present in any of the Argentinean samples.

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BACKGROUND AND OBJECTIVE: Even though herbal medicines have played an important role in disease management and health for many centuries, their present frequent use is challenged by the necessity to determine their complex composition and their multitarget mode of action. In the present study, modern methods were investigated towards their potential in the characterization of herbal substances. As a model the herbal substance Chelidonii herba was used, for which several reports on liver toxicities exist. Extracts of Chelidonii herba with different solvents were characterized phytochemically and functionally by experiments with HepG2 liver cells. METHODS: Chelidonii herba was extracted with four solvents of different polarity (dichloromethane, water, ethanol, and ethanol 50% (V/V); four replicates each). The different extracts were characterized metabolomically by (1)H-NMR fingerprinting analysis and principal component analysis (PCA). The content of alkaloids was additionally determined by RP-HPLC. Functional characterization was achieved by the determination of cell proliferation and by transcriptomics techniques (Whole Genome Gene Expression Microarrays v2, Agilent Technologies) in HepG2 cells after exposure to the different extracts (four experimental replicates each). RESULTS: Based on data from (1)H-NMR fingerprints and RP-HPLC analyses the different extracts showed a divergent composition of constituents depending on the solvent used. HepG2 liver cells responded differentially to the four extracts. Microarray analysis revealed a significant regulation of genes and signal cascades related to biotransformation. Also liver-toxic signal cascades were activated. Neither the activated genes nor the proliferation response could be clearly related to the differing alkaloid content of the extracts. CONCLUSION: Different manufacturing processes lead to different herbal preparations. A systems biology approach combining a metabolomic plant analysis with a functional characterization by gene expression profiling in HepG2 cells is an appropriate strategy to characterize variations in plant extracts. Safety assessments of herbal substances may benefit from such complementary analyses.

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Epinotia aporema granulovirus (EpapGV) has attracted interest as a potential biocontrol agent of the soybean pest Epinotia aporema in Argentina. Studies on virus/host interactions conducted so far have lacked an accurate method to assess the progress of virus load during the infection process. The present paper reports the development of a real-time PCR for EpapGV and its application to describe viral kinetics following ingestion of two different virus doses by last-instar E. aporema larvae. Real-time PCR was shown to be a reliable method to detect and quantify the presence of EpapGV in the analyzed samples. The increase in virus titer (log) exhibited a sigmoidal pattern, with an exponential growth phase between 24 and 48 h postinfection for both initial doses tested.

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Argentina suffered an extensive foot-and-mouth disease (FMD) epidemic between July 2000 and January 2002, 3 months after obtaining the official FMD-free without vaccination status conferred by the World Organization for Animal Health. This is one of the largest FMD epidemics controlled by implementation of a systematic mass vaccination campaign in an FMD-free country. In 2000, 124 herds were reported as FMD positive, 2394 herds in 2001 and one in January 2002; the total number of cattle herds in the country at that time was approximately 230 000. Estimates of FMD transmission are important to understand the dynamics of disease spread and for estimating the value for the parameterization of disease transmission models, with the ultimate goals of predicting its spread, assessing and designing control strategies, conducting economic analyses and supporting the decision-making process. In this study, the within-herd coefficient of transmission, ß, was computed for herds affected in the 2001 FMD epidemic and categorized as low or high based on the median value of ß. A logistic regression model was fitted to identify factors significantly associated with high values of ß. Results suggested that the odds of having a high within-herd transmission were significantly associated with time from initial herd infection to disease detection, date of report, vaccination, and time from initial herd infection to herd vaccination. Results presented in this study demonstrate, in quantifiable terms, the protective impact of vaccination in reducing FMD transmission in infected herds. These results will be useful for the parameterization of epidemiological models aimed at quantifying the impact of vaccination and for the design and implementation of FMD emergency vaccination strategies in face of an epidemic.

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HISTORY AND ADMISSION FINDINGS: A 70-year old woman was admitted by the emergency doctor directly to our cardiac catheterization unit with persisting chest pain 60 minutes after onset of symptoms. Except for hypertension and hypercholesterinemia there was no cardiac history. On examination we found a bradykardia of 43/minutes, no other pathological signs. DIAGNOSTIC PROCEDURES: The ECG showed significant ST-segment elevation in I, aVL, V4-V6, and revealed a complete dissociation between p-wave and QRS-complex. This led to the diagnose of a ST-elevation myocardial infarction of the lateral wall connected with a third degree AV-block. TREATMENT AND COURSE: First a transvenous pacing was done and the subsequent coronary angiography excluded coronary vascular disease. The laevocardiography showed an apical ballooning, therefore takotsubo cardiomyopathy could be diagnosed. Due to persisting third degree AV-Block, a permanent pacemaker was implanted on the fourth day of treatment. After one week the left ventricular function was nearly normal. The intravascular ultrasound excluded a ruptured plaque. CONCLUSION: In patients presenting acute coronary syndrom and apical ballooning, takotsubo cardiomyopathy should be considered after excluding coronary vascular disease. We presented a rare case of takotsubo cardiomyopathy together with a third degree AV-block. In spite of its persistence and the need of a permanent pacemaker implantation, the prognosis of the disease remained good.

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The optimal therapeutic approach to a patient who has a large incarcerated inguinal hernia and an abdominal aortic aneurysm (AAA) of significant size is controversial. Here we report a case of a patient who presented with a giant incarcerated inguinal hernia who was found to have an 8-cm AAA. Three surgical options were considered: (1) perform open AAA repair first, followed by hernia repair a few weeks later to allow for recovery, (2) perform hernia repair first followed by AAA repair a few weeks later, or (3) perform both simultaneously as a combination procedure. We successfully performed hernia repair first, followed by open AAA repair as a separate procedure at a later date. We believe that a two-stage approach, performing hernia repair first, is the safest approach to surgical repair of an incarcerated hernia in a patient with an asymptomatic AAA that requires open repair.

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Chicken infectious anemia virus (CAV) is a worldwide-distributed infectious agent that affects commercial poultry. Although this agent was first detected in Argentina in 1994, no further studies on CAV in this country were reported after that. The recent increased occurrence of clinical cases of immunosuppression that could be caused by CAV has prompted this study. Our results confirmed that CAV is still circulating in commercial flocks in Argentina. Phylogenetic analysis focusing on the VP1 nucleotide sequence showed that all Argentinean isolates grouped together in a cluster, sharing a high similarity (> 97%) with genotype B reference strains. However, Argentinean isolates were distantly related to other strains commonly used for vaccination in this country, such as Del-Ros and Cux-1. Sequence analysis of predicted VP1 peptides showed that most of the Argentinean isolates have a glutamine residue at positions 139 and 144, suggesting that these isolates might have a reduced spread in cell culture compared with Cux-1. In addition, a particular amino acid substitution at position 290 is present in all studied Argentinean isolates, as well as in several VP1 sequences from Malaysia, Australia, and Japan isolates. Our results indicate that it is possible to typify CAV strains by comparison of VPI nucleotide sequences alone because the same tree topology was obtained when using the whole genome sequence. The molecular analysis of native strains sheds light into the epidemiology of CAV in Argentinean flocks. In addition, this analysis could be considered in future control strategies focused not only on breeders but on broilers and layer flocks.

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Bovine viral diarrhoea virus (BVDV) is a pestivirus that infects mainly bovine cattle. Nevertheless, there are several reports about infections in other members of the Artiodactyla order including serological studies, that indicate infection of BVDV in buffaloes. The aim of this article is to study the presence of BVDV in three young water buffaloes, displaying nonspecific clinical signs, compatible with the BVDV infection. Both immunohistochemistry and RT-PCR confirmed the presence of BVDV in the animals. The sequence analysis on RT-PCR amplicons revealed high identity with reference strains of genotypes 1a and 1b. Although BVDV was unequivocally identified in the sick animals, it has not been proved it is responsible for the clinical signs. Further studies are needed to clarify the pathogenic role of BVDV infection in this animal species, and the role of buffaloes in the epidemiology of BVDV infection.

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During 2000-2002 a foot-and-mouth disease (FMD) epizootic affected Argentina and spread across the country resulting in more than 2500 outbreaks. In order to study the evolution of the FMD viruses (FMDV) and help with disease control measures, a genetic characterization and phylogenetic analysis was performed of 43 field isolates representative of the epizootic. The nucleotide sequence of the VP1-coding region was determined for the viruses and used in this study. Two serotype A lineages, A/Arg/00 and A/Arg/01 (1000/1000 bootstrap value) and two different serotype O/Arg/00 lineages (848/1000 bootstrap value) were identified. Phylogenetic analysis showed that viruses A/Arg/01 and O/Arg/00 could be related with former South American isolates, while the origin of A Argentina 2000 viruses remains unclear. Comparison of the amino acid sequences with vaccine reference strains revealed differences at critical antigenic sites for emergent strains A/Arg/00 and A/Arg/01, leading to a change in the current vaccine formulation.

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Alzheimer's disease is characterized by amyloid peptide formation and deposition, neurofibrillary tangles, central cholinergic dysfunction, and dementia; however, the relationship between these parameters is not well understood. We studied the effect of amyloid peptide formation and deposition on central cholinergic function in knock-in mice carrying the human amyloid precursor protein (APP) gene with the Swedish/London double mutation (APP-SL mice) which were crossbred with transgenic mice overexpressing normal (PS1wt) or mutated (M146L; PS1mut) human presenilin-1. APP-SLxPS1mut mice had increased levels of Abeta peptides at 10 months of age and amyloid plaques at 14 months of age while APP-SLxPS1wt mice did not have increased peptide levels and did not develop amyloid plaques. We used microdialysis in 15-27 months old mice to compare hippocampal acetylcholine (ACh) levels in the two mouse lines and found that extracellular ACh levels were slightly but significantly reduced in the APP-SLxPS1mut mice (-26%; P=0.044). Exploratory activity in the open field increased hippocampal ACh release by two-fold in both mouse lines; total and relative increases were not significantly different for the two strains under study. Similarly, infusion of scopolamine (1 microM) increased hippocampal ACh release to a similar extent (3-5-fold) in both groups. High-affinity choline uptake, a measure of the ACh turnover rate, was identical in both mouse lines. Neurons expressing choline acetyltransferase were increased in the septum of APP-SLxPS1mut mice (+26%; P=0.046). We conclude that amyloid peptide production causes a small decrease of extracellular ACh levels. The deposition of amyloid plaques, however, does not impair stimulated ACh release and proceeds without major changes of central cholinergic function.

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Ethnobotanical investigations led to the selection of 19 plant species, used traditionally in Sudan against malaria and other similar tropical diseases, for further studies. Pamianthe peruviana (Amaryllidaceae) exhibited significant activity against a chloroquine-resistant Plasmodium falciparum strain (K1) and a chloroquine-sensitive strain (NF54) with IC(50) values of 0.6 and 1.1 microg/ml, respectively. Additionally, P. peruviana showed considerable activities against Trypanosoma brucei rhodesiense (IC(50) 1.5 microg/ml) and T. cruzi (IC(50) 11.8 microg/ml). The antiplasmodial activity of the different extracts of Salvadora persica (Salvadoraceae) against P. falciparum NF54 strain were found to be 0.6 microg/ml (stems) and 0.7 microg/ml (leaves). Extracts of different parts of Combretum hartmannianum (Combretaceae) possessed significant activity against the chloroquine-sensitive P. falciparum strain (NF54) with IC(50) values of 0.2 microg/ml (bark), 0.4 microg/ml (stem) and 4.3 microg/ml (leaves). Most interestingly, the extracts of the leaves of C. hartmannianum totally inhibited the enzyme HIV-1 reverse transcriptase (HIV-1 RT) at a concentration of 66 microg/ml. A comparably strong activity against p56(lck) tyrosine kinase was also seen for this extract.

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The complete nucleotide sequence of foot-and-mouth disease virus (FMDV) South American strain O(1) Campos/Bra/58 was determined. The 8,168 Kb sequence and the deduced amino acid sequence were compared to published FMDV sequences. They showed the highest sequence homology with the O(1) Kaufbeuren/FRG/66 strain, but closer evolutionary relatedness to the Argentinean strains.

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We present a case of two patients with a distal femur shaft fracture due to a high velocity trauma. Both were treated with a distal femur nail (DFN). After mobilisation a fracture of the neck of the femur was diagnosed which was not seen in the x-rays on admission. In this paper we discuss whether this is a typical constellation of ipsilateral fractures of the neck of the femur in femur shaft fractures or a complication of implantation of a DFN. Immediately after operative treatment of a femur shaft fracture specifically after high velocity trauma or in polytraumatized patients an x-ray of the hip in two plains should be made in the same narcosis. A possible fracture of the neck of the femur could be treated at same time. Post-operatively a further diagnostic should be done in case of suspicion, e.g. pain during mobilisation.

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The reduction-cascade of PETN is described as a combination of cyclic-voltammetric measurements and analytical results together with synthesis of PETN-metabolites; furthermore the electroreduction of pentaerythityldinitrate (PEDN) in the presence and absence of cystine as well as cystine and electrogenerated superoxide-radicalanions to elucidate the interaction of PETN with thiol-species. PETN was recognized as precursor for a initial radicalic process, followed by intermediate formation of pentaerythityltrinitratealdehyde (PENA) inside a self-reducing nitrate-system with NO as final product, which may explain its special position in comparison with other pharmaceutically applied nitratestructures. It could be proved, that a cystine-pool reacts as a selective moderator inside the reduction of PEDN without being interfered by O2.-, yielding pentaerythitylmononitrate (PEMN) meanwhile in the absence of cystine only pentaerythrite (PE) is formed.

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We have analysed complete or partial VPI sequences of 31 foot-and-mouth disease (FMD) viruses belonging to serotypes A, O and C to determine the genetic relatedness of field strains of FMD virus (FMDV) that have circulated in Argentina between 1961 and 1994. Phylogenetic analysis, which also included 15 previously published Argentinean sequences and six reference strains, revealed that (i) FMD type A strains showed the highest genetic heterogeneity and could be divided into five lineages with a sequence divergence of 0.9-18.5% between strains (ii) most of the FMD type O viruses grouped in two clusters (within cluster sequence divergence ranging from 0.2% to 6.0%) circulating in Argentina since the early 1960s, and (iii) FMD type C viruses were grouped in two clusters with a 13.4% nucleotide sequence divergence between each cluster. The availability of sequence data for many more field isolates from the region will enable us to understand the genetic relationships between FMDV strains and to rapidly trace the source of an FMD outbreak for epidemiological surveillance.

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Nucleotide sequence and phylogenetic analysis of the VP1 structural protein have been used extensively as diagnostic and epidemiological tools for foot and mouth disease virus (FMDV). In this report we have applied this methodology to the analysis of the VP1 coding sequence from FMDV strains isolated in Argentina during 1993-1994. The results demonstrated that the field isolates were related to the vaccine strains used at that time. However the involvement of the vaccine virus appeared to be different for outbreaks caused by FMD viruses type O or C. These data provide a database essential for determining the origin of new epizootics.

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