bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcript analysis reveals an extended regulon and the importance of protein–protein co-operativity for the Escherichia coli methionine repressor
Authors: Marincs Ferenc , Manfield Iain W. , Stead Jonathan A. , Mcdowall Kenneth J. , Stockley Peter G.
Published: June 2006

We have used DNA arrays to investigate the effects of knocking out the methionine repressor gene, metJ, on the Escherichia coli transcriptome. We assayed the effects in the knockout strain of supplying wild-type or mutant MetJ repressors from an expression plasmid, thus establishing a rapid assay for in vivo effects of mutations characterized previously in vitro. Repression is largely restricted to known genes involved in the biosynthesis and uptake of methionine. However, we identified a number of additional genes that are significantly up-regulated in the absence of repressor. Sequence analysis of the 5′ promoter regions of these genes identified plausible matches to met-box sequences for three of these, and subsequent electrophoretic mobility-shift assay analysis showed that for two such loci their repressor affinity is higher than or comparable with the known metB operator, suggesting that they are directly regulated. This can be rationalized for one of the loci, folE, by the metabolic role of its encoded enzyme; however, the links to the other regulated loci are unclear, suggesting both an extension to the known met regulon and additional complexity to the role of the repressor. The plasmid gene replacement system has been used to examine the importance of protein–protein co-operativity in operator saturation using the structurally characterized mutant repressor, Q44K. In vivo, there are detectable reductions in the levels of regulation observed, demonstrating the importance of balancing protein–protein and protein–DNA affinity.
Role of P1 residues Arg336 and Arg562 in the activated-Protein-C-catalysed inactivation of Factor VIIIa
Authors: Varfaj Fatbardha , Neuberg Julie , Jenkins P. Vincent , Wakabayashi Hironao , Fay Philip J.
Published: June 2006

APC (activated Protein C) inactivates human Factor VIIIa following cleavage at residues Arg336 and Arg562 within the A1 and A2 subunits respectively. The role of the P1 arginine in APC-catalysed inactivation of Factor VIIIa was examined by employing recombinant Factor VIIIa molecules where residues 336 and 562 were replaced with alanine and/or glutamine. Stably expressed Factor VIII proteins were activated by thrombin and resultant Factor VIIIa was reacted at high concentration with APC to minimize cofactor inactivation due to A2 subunit dissociation. APC cleaved wild-type Factor VIIIa at the A1 site with a rate ∼25-fold greater than that for the A2 site. A1 mutants R336A and R336Q were inactivated ∼9-fold slower than wild-type Factor VIIIa, whereas the A2 mutant R562A was inactivated ∼2-fold slower. No cleavage at the mutated sites was observed. Taken together, these results suggested that cleavage at the A1 site was the dominant mechanism for Factor VIIIa inactivation catalysed by the proteinase. On the basis of cleavage at Arg336, a Km value for wild-type Factor VIIIa of 102 nM was determined, and this value was significantly greater than Ki values (∼9–18 nM) obtained for an R336Q/R562Q Factor VIIIa. Furthermore, evaluation of a series of cluster mutants in the C-terminal region of the A1 subunit revealed a role for acidic residues in segment 341–345 in the APC-catalysed proteolysis of Arg336. Thus, while P1 residues contribute to catalytic efficiency, residues removed from these sites make a primary contribution to the overall binding of APC to Factor VIIIa.
The impact of breeding to reduce residual feed intake on enteric methane emissions from the Australian beef industry
Authors: Alford A. R. , Hegarty R. S. , Parnell P. F. , Cacho O. J. , Herd R. M. , Griffith G. R.
Published: June 2006

The expected reduction in methane emissions from the Australian beef herd resulting from using bulls identified as being more feed efficient as a result of having a lower residual feed intake (RFI) was modelled, both in a single herd in southern Australia and in the national herd. A gene flow model was developed to simulate the spread of improved RFI genes through a breeding herd over 25 years, from 2002 to 2026. Based on the estimated gene flow, the voluntary feed intakes were revised annually for all beef classes using livestock populations taken from the Australian National Greenhouse Gas Inventory (NGGI). Changes in emissions (kg methane/animal.year) associated with the reduction in feed intake were then calculated using NGGI procedures. Annual enteric methane emissions from both the individual and national herd were calculated by multiplying the livestock numbers in each beef class by the revised estimates of emissions per animal. For an individual adopting herd, the annual methane abatement in year 25 of selection was 15.9% lower than in year 1. For the national herd, differential lags and limits to adoption were assumed for northern and southern Australia. The cumulative reduction in national emissions was 568 100 t of methane over 25 years, with annual emissions in year 25 being 3.1% lower than in year 1. It is concluded that selection for reduced RFI will lead to substantial and lasting methane abatement, largely as a consequence of its implementation as a breeding objective for the grazing beef herd.
Sire and dam breed effects on fatty acid profiles in the longissimus dorsi muscle and subcutaneous fat of beef cattle
Authors: Graham J. F. , Bernaud E. , Deland M. P. B.
Published: June 2006

This study investigated the effect of sire and dam breed on the fatty acid profiles of muscle and subcutaneous fat in beef cattle. Seven hundred and ninety-three steer and 222 female progeny derived from mating Angus and Hereford cows to Angus, Hereford, Limousin and Simmental bulls, were slaughtered at around 2 years of age (about 540 kg liveweight). The mean fat content of the longissimus dorsi muscle ranged from 4.6% for the Limousin-sired cattle to 6.0% for the Angus-sired cattle. Breed differences occurred in the majority of fatty acids from the intramuscular fat, but fewer differences were observed from the subcutaneous fat. The Limousin- and Simmental-sired progeny had less (P<0.001) saturated fat and more (P<0.001) unsaturated intramuscular fat compared with the Angus- and Hereford-sired cattle. The Angus and Simmental cattle had more (P<0.001) monounsaturates than the Limousin and Hereford cattle. There were differences (P<0.001) in the level of intramuscular polyunsaturates between all 4 sire-breeds, the Limousin having the highest and Angus the lowest. Simmental progeny had significantly higher levels of polyunsaturated fatty acids, compared with the Hereford-sired progeny, as well as a higher monousaturated : saturated fatty acid ratio. Hereford-sired progeny had a lower (P<0.001) monousaturated : saturated fatty acid ratio in the intramuscular fat. Intramuscular fatty acids were affected by dam breed, with progeny of Hereford cows having a higher percentage of unsaturated fatty acids (P = 0.015), lower saturated fatty acids (P = 0.011), and a higher monousaturated : saturated fatty acid ratio (P = 0.028) than those of Angus cows. There was no effect of dam breed on the totals of the different fatty acid groups in the subcutaneous fat. The subcutaneous fat had higher levels of saturated fatty acids and lower levels of unsaturated and polyunsaturated fatty acids compared with the intramuscular fat. Although the differences reported were generally small, it would seem that there may be scope to utilise these genetic differences to produce meat with more desirable fatty acid characteristics.
Eating quality of conventionally chilled sheep meat
Authors: Hopkins D. L. , Toohey E. S.
Published: June 2006

The meat and eating quality of the M. longissimus et lumborum (LL) from 80 adult sheep carcasses was examined. Half of the carcasses were subjected to the full range of electrical inputs that are routinely used at the abattoir: immobilisation, spinal discharge and high voltage stimulation (HVS), whereas the other half of the carcasses were subjected to all electrical inputs except HVS. HVS significantly decreased the first pH values and increased the average predicted temperature at pH 6.0. When the shear force of samples aged for 1 day was examined (n = 77), there was a significant effect of stimulation, such that non-stimulated meat was tougher. For a reduced sample (n = 40), the most influential effect on shear force was aging, with no significant effect of stimulation or interaction between stimulation and aging. This was such that aging reduced the percentage of samples with a shear force above 50 N from 75% after 1 day to 17.5% after 7 days of aging for the 40 LLs. When the LLs were aged for 7 days, there was no effect of stimulation on eating quality traits including tenderness, flavour, juiciness or overall liking. Based on the data for the LLs aged for 7 days, a relationship between overall liking and the overall ranking score was derived. Predicted overall liking scores at each rating score were derived, from which it was determined that to achieve a rating score of 3 (good every day), the overall liking score had to be 57. There was a significant interaction between category (less or greater than 57) and stimulation, such that for the less than 57 category, the mean overall liking score was lower for samples from non-stimulated carcasses (46.1) than those from stimulated carcasses (54.4). In the greater than 57 category, there was no difference between stimulated and non-stimulated samples with mean overall liking scores of 67.2 and 70.8, respectively. In total, 14% of samples had overall liking scores below 57. These results show that the proportion of very poor samples is reduced with stimulation even with aging and this is a very important outcome.
Relationship between animal age, intramuscular fat, cooking loss, pH, shear force and eating quality of aged meat from sheep
Authors: Hopkins D. L. , Hegarty R. S. , Walker P. J. , Pethick D. W.
Published: June 2006

The relationships between sensory traits (tenderness, juiciness, flavour and overall liking) and objective measures, such as shear force, intramuscular fat, cooking loss, pH and animal age, were derived for M. longissimus thoracis et lumborum (LL) from 471 lamb and sheep carcasses. Tenderness could be predicted with the most accuracy (R2 = 0.24) and flavour with the highest precision (r.s.d. = 7.5 units) when using the objective measures, which may be in part due to the small variation in the range of shear force values of the samples (all carcasses electrically stimulated and meat aged for 5 days) and the use of consumer panels for the assessment of sensory traits. The ultimate pH of the LL, the rate of decline in pH in the LL or the predicted temperature at pH 6.0 were not significant predictors of the sensory traits when tested on a subsample of the carcasses. The model coefficients indicated that all sensory traits (tenderness, flavour, juiciness and overall liking) declined as shear force and age increased, and as intramuscular fat percentage decreased. This translated into a decline of 16 points on average for tenderness and 13 points for overall liking when LL samples from 68.5-month-old sheep were compared with those from unweaned lambs, when adjusted to the same level of intramuscular fat and shear force. Predictions of the sensory traits at varying levels of shear force were made and show that at 49 Newtons (N), the overall liking score would be 51 and the tenderness score 48. Derived relationships between objective meat quality measures and sensory traits suggest that to achieve a failure rate of no more than 10% for loin meat when eaten, it must have a shear force of about 27 N or less.
Intake and productivity of lambs grazing leafy or stemmy forage rape and the effect of energy or protein supplements
Authors: Dove H. , Milne J. A.
Published: June 2006

Weaned lambs grazed forage rape in a leader-follower grazing system to create leafy and stemmy swards. Stemmy swards had a lower herbage mass and leaf content, a much higher stem and neutral detergent fibre content, and a lower N content. Lambs grazing both swards were given either no supplement or daily supplements of rolled barley (energy) or rolled barley plus formaldehyde-treated soyabean meal (protein). Half the lambs in one replicate were also given supplementary copper to counter possible effects of S-methyl-L-cysteine sulphoxide ingestion from the forage rape. The copper supplement had significant effects on liver copper content, plasma copper and the percentage of red blood cells with Heinz bodies, but there was no effect on liveweight gain compared with lambs which did not receive copper. Lambs grazing the stemmy sward ate less herbage, but much more of the supplements, in both absolute and proportional terms. Herbage intake was not influenced by supplement type. Substitution between herbage and supplement was low (<0 to 12%) and not notably different between the crop types or supplements. Liveweight gains on the leafy crop (160–200 g/day) were higher than on the stemmy crop (114–143 g/day) with significantly higher gains in lambs given the protein supplement. Supplementation did not influence carcass weight or the rates of carcass protein or fat gain, which were all higher in lambs grazing the leafy crop. The results suggest that protein supplements may improve the liveweight gain of lambs grazing forage rape.
Growth and carcass characteristics of Wagyu-sired steers at heavy market weights following slow or rapid growth to weaning
Authors: Cafe L. M. , Hearnshaw H. , Hennessy D. W. , Greenwood P. L.
Published: June 2006

Two groups of Wagyu × Hereford steers grown slowly (slow preweaning group, n = 14, mean average daily gain = 631 g/day) or rapidly (rapid preweaning group, n = 15, mean average daily gain = 979 g/day) from birth to weaning were backgrounded on improved, temperate pasture to equivalent group liveweights (543 v. 548 kg, s.e. = 8.8 kg), then finished in a feedlot for 120 days. At weaning, the slow preweaning group was 79 kg lighter than the rapid preweaning group. They required an additional 43 days of backgrounding to reach the same feedlot entry weight as the rapid preweaning group. The slow preweaning group grew more rapidly during backgrounding (630 v. 549 g/day, s.e. = 13.7 g/day) but tended to grow more slowly during feedlotting (1798 v. 1982 g/day, s.e. = 74.9 g/day) than their rapid preweaning counterparts, with overall growth rates from weaning to feedlot exit not differing between the 2 groups (rapid 763 g/day v. slow 772 g/day, s.e. = 17.5 g/day). At slaughter, following the feedlot phase, carcass weights of the 2 groups did not differ significantly (rapid 430 kg v. slow 417 kg, s.e. = 7.2 kg). There was a tendency for the steers grown slowly to weaning to have a higher dressing percentage (57.6 v. 56.6%, s.e. = 0.33%), but there were no significant differences in carcass compositional characteristics between the 2 groups. The slow preweaning steers did have a greater eye muscle area than the rapid preweaning steers (106.6 v. 98.9 cm2, s.e. = 1.87) when carcass weight was used as a covariate. These findings demonstrate that cattle grown slowly to weaning have similar composition at slaughter as those grown rapidly during the same period when backgrounded on pasture to the same feedlot entry weight. Furthermore, marbling was not adversely affected by slow growth to weaning.
Genetic changes generated within the Katanning Merino Resource flocks
Authors: Greeff J. C. , Cox G.
Published: June 2006

Genetic changes for clean fleece weight, fibre diameter and hogget body weight were determined in the Katanning Merino Resource flocks from 1982 to 2004. From 1982 to 1992 genetic trends are presented for individual studs that used mainly subjective classing selection methods (Phase 1) and the genetic trends from 1997 to 2004 demonstrate the genetic changes that can be achieved from using estimated breeding values calculated from best linear unbiased prediction (BLUP) mixed methodology (Phase 2). The results during the first phase show that very few genetic changes occurred in most studs, except for the 4 studs of the Performance Sheep Breeding strain which showed genetic increases in hogget body weight. The genetic trends show that some studs generated change towards their breeding objective, while others show no changes or changes in the opposite direction. In contrast, the use of BLUP estimated breeding values resulted in positive changes in clean fleece weight, fibre diameter and body weight in accordance with the defined breeding objectives.
A strategic approach to mitigating the impacts of wild canids: proposed activities of the Invasive Animals Cooperative Research Centre
Authors: Fleming P. J. S. , Allen L. R. , Lapidge S. J. , Robley A. , Saunders G. R. , Thomson P. C.
Published: June 2006

Wild canids (wild dogs and European red foxes) cause substantial losses to Australian livestock industries and environmental values. Both species are actively managed as pests to livestock production. Contemporaneously, the dingo proportion of the wild dog population, being considered native, is protected in areas designated for wildlife conservation. Wild dogs particularly affect sheep and goat production because of the behavioural responses of domestic sheep and goats to attack, and the flexible hunting tactics of wild dogs. Predation of calves, although less common, is now more economically important because of recent changes in commodity prices. Although sometimes affecting lambing and kidding rates, foxes cause fewer problems to livestock producers but have substantial impacts on environmental values, affecting the survival of small to medium-sized native fauna and affecting plant biodiversity by spreading weeds. Canid management in Australia relies heavily on the use of compound 1080-poisoned baits that can be applied aerially or by ground. Exclusion fencing, trapping, shooting, livestock-guarding animals and predator calling with shooting are also used. The new Invasive Animals Cooperative Research Centre has 40 partners representing private and public land managers, universities, and training, research and development organisations. One of the major objectives of the new IACRC is to apply a strategic approach in order to reduce the impacts of wild canids on agricultural and environmental values in Australia by 10%. In this paper, the impacts, ecology and management of wild canids in Australia are briefly reviewed and the first cooperative projects that will address IACRC objectives for improving wild dog management are outlined.
Regulation of transactivation-independent proapoptotic activity of p53 by FOXO3a
Authors: You Han , Yamamoto Kazuo , Mak Tak Wah
Published: June 2006

The tumor suppressor p53 can trigger cell death independently of its transcriptional activity through subcellular translocation and activation of proapoptotic Bcl-2 family members. The regulation of such activity of endogenous p53 in response to stress remains largely unknown. Here we show that nuclear, activated FOXO3a could impair p53 transcriptional activity. However, activation of FOXO3a either on serum starvation or by expressing a constitutively active form of FOXO3a could induce p53-dependent apoptosis, even in cells bearing a transcriptionally inactive form of p53. Furthermore, FOXO3a could promote p53 cytoplasmic accumulation by increasing its association with nuclear exporting machinery. Our data also suggest that PUMA and Bax are required for p53-dependent apoptosis in manner that is independent of p53 transcriptional activity.
Dimerization-induced corepressor binding and relaxed DNA-binding specificity are critical for PML/RARA-induced immortalization
Authors: Zhou Jun , Pérès Laurent , Honoré Nicole , Nasr Rihab , Zhu Jun , de Thé Hugues
Published: June 2006

The pathogenesis of acute promyelocytic leukemia involves the transcriptional repression of master genes of myeloid differentiation by the promyelocytic leukemia–retinoic acid receptor α (PML/RARA) oncogene. PML-enforced RARA homodimerization allows the tighter binding of corepressors, silencing RARA target genes. In addition, homodimerization dramatically extends the spectrum of DNA-binding sites of the fusion protein compared with those of normal RARA. Yet, any contribution of these two properties of PML/RARA to differentiation arrest and immortalization of primary mouse hematopoietic progenitors was unknown. We demonstrate that dimerization-induced silencing mediator of retinoid and thyroid receptors (SMRT)-enhanced binding and relaxed DNA-binding site specificity are both required for efficient immortalization. Thus, enforced RARA dimerization is critical not only for triggering transcriptional repression but also for extending the repertoire of target genes. Our studies exemplify how dimerization-induced gain of functions converts an unessential transcription factor into a dominant oncogenic protein.
Training-induced energy balance mismatch in Standardbred mares
Authors: Gordon ME , McKeever KH , Bokman S , Betros CL , Manso-Filho HC , Liburt NR , Streltsova JM
Published: June 2006

This study tested the hypothesis that exercise training would alter feed intake (FI), body composition (BC) and plasma concentrations of active ghrelin, leptin, cortisol, insulin and glucose. Eight Standardbred mares (12±2 years, 509±36 kg body weight (BW), mean±SD) were trained (EX) in an equine Equi-ciser (initially 3 days per week at 60% maximal heart rate (HRmax) for 20 min and gradually increased to 5 days per week at 70% HRmaxfor 30 min, with a 10-min warm-up and 10-min cool-down period at the walk). Six mares (12±2 years, 537±45 kg) served as non-exercise controls (CON). All mares were unfit and had not been subjected to conditioning for 3 years before the experiment. Pre- and post-training incremental exercise tests (GXT) were run to determine HRmaxand maximal oxygen uptake (VO2max). A total mixed ration (TMR) of hay cubes was fed free choice for 16 h day-1with the primary experiment following a 6-week diet adaptation period. Mares' FI was measured daily and reported in grams per kilogram BW of feed eaten per week. Changes in BC were assessed using BW (electronic scale) and percentage fat calculated using rump fat thickness and the Westervelt equation. Blood samples were taken every 2 weeks at 15:25, before mares were given their allotment of hay cubes on a day when they did not exercise, to measure plasma hormone and glucose concentrations. Gastroscopy for gastric ulcers was performed before, during and after the trial. VO2maxincreased by 7.0% (P<0.03) in EX, but did not change (P>0.05) in CON. FI decreased (P<0.001) in both groups, but was only different (P<0.02) between EX and CON at week 3. Digestible energy (DE) intake (Mcal day-1) was initially higher (P<0.001) than calculated DE requirements in EX. However, over time, DE only matched and then fell below (P<0.03) the DE intake required for training. In CON horses, DE intake was higher (P<0.001) than calculated requirements. BW and percentage body fat increased (P<0.001) over time in EX and CON. Plasma leptin concentration increased (P<0.001) over time in both groups, but was 60% higher (P<0.04) in CON compared to EX at weeks 4–8. There were no differences (P>0.05) in active ghrelin, glucose, insulin or cortisol between the groups and over time. Five out of seven EX mares developed gastric ulcers. No CON mares developed gastric ulcers. Training was associated with changes in plasma leptin concentration, an increased incidence of gastric ulcers and a disruption of the balance between required DE and actual intake.
Effect of A Hospital Campaign for Influenza Vaccination of Healthcare Workers
Authors: Song Joon Young , Park Cheong Won , Jeong Hye Won , Cheong Hee Jin , Kim Woo Joo , Kim Sung Ran
Published: June 2006

Objective.

To identify the factors that inhibit or motivate influenza vaccination among healthcare workers (HCWs).

Methods.

In March 2000, we prepared 34-item questionnaire for both vaccine recipients and nonrecipients regarding demographic characteristics, factors motivating and inhibiting vaccination, and knowledge and attitudes about influenza vaccination. On the basis of the results of our survey, an aggressive hospital vaccination campaign was undertaken. In April 2004, after the 4-year campaign, the same questionnaire was again administered to HCWs.

Results.

In both 2000 and 2004, the main motives for undergoing influenza vaccination were “hospital campaign” and “recommendation by colleagues”; the percentage of respondents who were motivated by the hospital campaign had remarkably increased from 27% in 2000 to 52% in 2004 (P<.001), whereas the percentage who were motivated by recommendation by colleagues had not changed significantly (21% vs 14%). Qverall, the 4 reasons most frequently cited by HCWs for noncompliance with vaccination were insufficient available time, confidence in their health, doubt about vaccine efficacy, and fear of injection. In 2000, vaccination rates were below 30%, irrespective of occupation. After an aggressive vaccination campaign, the increase in the vaccination rate was highest among the nursing staff, increasing from 21% in 2000 to 92% in 2004, whereas the vaccination rate among the physicians was still below 60%.

Conclusion.

We conclude that a hospital campaign can markedly improve influenza vaccination rates among HCWs. Both a mobile cart system and free vaccine supply contributed to improving the vaccination rates in our study. In addition, a specifically tailored intervention strategy was required.
Infection Control in Pediatric Extended Care Facilities
Authors: Harris Jo-Ann S.
Published: June 2006

Pediatric extended care facilities provide for the biopsychosocial needs of patients younger than 21 years of age who have sustained self-care deficits. These facilities include long-term and residential care facilities, chronic disease and specialty hospitals, and residential schools. Infection control policies and procedures developed for adult long-term care facilities, primarily nursing homes for elderly people, are not applicable to long-term care facilities that serve pediatric patients. This article reviews the characteristics of pediatric extended care facilities and their residents, and the epidemic and endemic nosocomial infections, infection control programs, and antimicrobial resistance profiles found in pediatric extended care facilities.
Feasibility of Azithromycin Prophylaxis During a Pertussis Outbreak Among Healthcare Workers in a University Hospital in Paris
Authors: Giugliani Camila , Vidal-Trécan Gwenaëlle , Traore Souleymane , Blanchard Hervé , Spiridon Gabriela , Rollot Florence , Launay Odile , Gorodestski Myriam , Marande Jean-Luc , Vinsonneau Christophe , Guillevin Loïc , Salmon-Céron Dominique
Published: June 2006

The objective of the present study was to evaluate the feasibility of azithromycin prophylaxis with respect to tolerability and compliance during a pertussis outbreak among healthcare workers in a university hospital ward. Compliance with the prophylaxis regimen was 89%; compliance was 75% from intent-to-treat perspective. The rate of adverse events was 33%. Female sex was associated with reporting of adverse events. Nonstudents and healthcare workers who reported adverse events were less compliant with the prophylaxis regimen.
Negative regulation of hepatitis B virus replication by cellular Hsp40/DnaJ proteins through destabilization of viral core and X proteins
Authors: Sohn Sook-Young , Kim Sun-Bum , Kim Joon , Ahn Byung-Yoon
Published: June 2006

The hepatitis B virus core protein consists of an amino-terminal capsid-assembly domain and a carboxyl-terminal RNA-binding domain. By using the yeast two-hybrid system, two Hsp40/DnaJ chaperone-family proteins, Hdj1 and hTid1, that interact with the carboxyl-terminal region (aa 94–185) of the core protein were identified. Hdj1 is the prototype member of the family and hTid1 is the human homologue of the Drosophila tumour-suppressor protein Tid56. Binding of the viral core protein with the Hsp40 proteins was confirmed by affinity chromatography and immunoprecipitation of transiently expressed proteins. Moreover, in a sucrose gradient, the precursor form of hTid1 co-sedimented with capsid-like particles composed of the full-length core protein. Unlike the general perception of the role of the cellular chaperone proteins in assisting viral protein folding and thus enhancing virus replication, ectopic expression of Hdj1 and hTid1 suppressed replication of HBV in transfected human hepatoma cells. Conversely, RNA interference-mediated knock-down of hTid1 resulted in increased HBV replication. It was found that both Hsp40 proteins specifically accelerated degradation of the viral core and HBx proteins. Our results suggest that the cellular chaperones, through destabilization of viral proteins, exert inhibitory functions on virus replication and hence may play suppressive roles in hepatocellular carcinoma.
Reduced ability of newborns to produce CCL3 is associated with increased susceptibility to perinatal human immunodeficiency virus 1 transmission
Authors: Meddows-Taylor Stephen , Donninger Samantha L. , Paximadis Maria , Schramm Diana B. , Anthony Fiona S. , Gray Glenda E. , Kuhn Louise , Tiemessen Caroline T.
Published: June 2006

The role of CC chemokines in protection against mother-to-child human immunodeficiency virus type 1 (HIV-1) transmission is not well understood. It was observed that mitogen-induced production of CCL3 and CCL4 by cord-blood mononuclear cells was increased among infants born to HIV-positive compared with HIV-negative mothers, and that a deficiency in production of CCL3 was associated with increased susceptibility to intrapartum HIV-1 infection. CCL3-L1 gene copy number was associated with CCL3 production and with vertical transmission. However, at equivalent CCL3-L1 gene copy numbers, infants who acquired HIV-1 infection relative to their exposed but uninfected counterparts had lower production of CCL3, suggesting that they may harbour some non-functional copies of this gene. Nucleotide changes that may influence CCL3 production were evident in the CCL3 and CCL3-L1 genes upstream of exon 2. Our findings suggest that infants who display a deficient-production phenotype of CCL3 are at increased risk of acquiring HIV-1, indicating that this chemokine in particular plays an essential role in protective immunity.
Porcine reproductive and respiratory syndrome virus strains of exceptional diversity in eastern Europe support the definition of new genetic subtypes
Authors: Stadejek T. , Oleksiewicz M. B. , Potapchuk D. , Podgórska K.
Published: June 2006

Porcine reproductive and respiratory syndrome virus (PRRSV) ORF5 and ORF7 sequences from Belarus were found to be of the European (EU) genotype, but grouped separately from all other EU genotype sequences described so far, including live-attenuated EU genotype PRRSV vaccines and Italian EU genotype sequences, some of which have been associated with reduced vaccine efficacy. Also, the Belarusian EU-PRRSV exhibited extreme ORF7 size polymorphism, ranging from 375 nt (the smallest EU genotype ORF7 yet described) to 393 nt (the largest ORF7 yet described for any arterivirus). With the Belarusian sequences, the diversity of EU genotype PRRSV now exceeds that of the North American (US) genotype PRRSV, suggesting a European origin of PRRSV. Finally, a very sharp geographical demarcation of highly diverse EU genotype PRRSV was observed along the eastern Polish border. The new Belarusian sequences have relevance for vaccine and diagnostic-antigen design and show that sequence analysis of PRRSV from more eastern parts of Europe may offer further insights into the emergence and evolution of PRRSV.
Sequence analysis of the Choristoneura occidentalis granulovirus genome
Authors: Escasa Shannon R. , Lauzon Hilary A. M. , Mathur Amanda C. , Krell Peter J. , Arif Basil M.
Published: June 2006

The genome of the Choristoneura occidentalis granulovirus (ChocGV) isolated from the western spruce budworm, Choristoneura occidentalis, was sequenced completely. It was 104 710 bp long, with a 67.3 % A+T content and contained 116 potential open reading frames (ORFs) covering 88.4 % of the genome. Of these, 29 ORFs were conserved in all fully sequenced baculovirus genomes, 30 were GV-specific, 53 were present in some nucleopolyhedroviruses (NPVs) and/or GVs, three were common to ChocGV and Choristoneura fumiferana GV (ChfuGV) and one was so far unique. To date, ChocGV is the only GV identified that contains a homologue of the apoptosis inhibitor protein P35/P49, present in some group I NPVs. It is also the first GV without a Xestia c-nigrum GV ORF 26 homologue. Five homologous regions (hrs)/repeat regions, lacking typical NPV hr palindromes were identified. ChocGV hrs were similar to each other but not to other GV hrs. A 1.8 kb repeat region with a high A+T content (81 %) and multiple repeats of 21–210 bp was found between choc36 and 37. This area resembled the non-homologous region origin of DNA replication (non-hr ori) identified in Cryptophlebia leucotreta GV (CrleGV) and Cydia pomonella GV (CpGV). Based on the mean amino acid identities of homologous proteins, ChocGV was closest to fully sequenced genomes CpGV (52.3 %) and CrleGV (52.1 %). The closest amino acid identity was to individual ORFs from the partially sequenced ChfuGV genome (97.2 % in 38 ORFs). Phylogenetic analysis placed ChocGV in a clade with CrleGV and CpGV.
A mouse model of persistent brain infection with recombinant Measles virus
Authors: Schubert S. , Möller-Ehrlich K. , Singethan K. , Wiese S. , Duprex W. P. , Rima B. K. , Niewiesk S. , Schneider-Schaulies J.
Published: June 2006

Measles virus (MV) nucleocapsids are present abundantly in brain cells of patients with subacute sclerosing panencephalitis (SSPE). This invariably lethal brain disease develops years after acute measles as result of a persistent MV infection. Various rodent models for MV infection of the central nervous system (CNS) have been described in the past, in which the detection of viral antigens is based on histological staining procedures of paraffin embedded brains. Here, the usage of a recombinant MV (MV-EGFP-CAMH) expressing the haemagglutinin (H) of the rodent-adapted MV-strain CAM/RB and the enhanced green fluorescent protein (EGFP) is described. In newborn rodents the virus infects neurons and causes an acute lethal encephalitis. From 2 weeks on, when the immune system of the genetically unmodified animal is maturating, intracerebral (i.c.) infection is overcome subclinically, however, a focal persistent infection in groups of neurons remains. The complete brain can be analysed in 50 or 100 μm slices, and infected autofluorescent cells are readily detected. Seven and 28 days post-infection (p.i.) 86 and 81 % of mice are infected, respectively, and virus persists for more than 50 days p.i. Intraperitoneal immunization with MV 1 week before infection, but not after infection, protects and prevents persistence. The high percentage of persistence demonstrates that this is a reliable and useful model of a persistent CNS infection in fully immunocompetent mice, which allows the investigation of determinants of the immune system.
Latency and reactivation of human cytomegalovirus
Authors: Sinclair John , Sissons Patrick
Published: June 2006

Human cytomegalovirus (HCMV) persists as a subclinical, lifelong infection in the normal human host, maintained at least in part by its carriage in the absence of detectable infectious virus – the hallmark of latent infection. Reactivation from latency in immunocompromised individuals, in contrast, often results in serious disease. Latency and reactivation are defining characteristics of the herpesviruses and key to understanding their biology. However, the precise cellular sites in which HCMV is carried and the mechanisms regulating its latency and reactivation during natural infection remain poorly understood. This review will detail our current knowledge of where HCMV is carried in healthy individuals, which viral genes are expressed upon carriage of the virus and what effect this has on cellular gene expression. It will also address the accumulating evidence suggesting that reactivation of HCMV from latency appears to be linked intrinsically to the differentiation status of the myeloid cell, and how the cellular mechanisms that normally control host gene expression play a critical role in the differential regulation of viral gene expression during latency and reactivation.
Identification and localization of hormone‐producing cells in the pituitary of male Padogobius martensi(Pisces, Gobiidae): a histochemical and immunocytochemical study
Authors: Cinquetti R. , Dramis L.
Published: June 2006

The adenohypophysial cell types of the adult male freshwater goby Padogobius martensi were identified and localized using histochemical and immunocytochemical techniques. Lactotropes were arranged in an irregular mass which occupied a major portion of the rostral pars distalis(RPD). Lead haematoxylin (PbH) stained the corticotropes selectively. These cells formed large clusters or islets between the neurohypophysial branches penetrating the RPD and the lactotropes. In addition, few isolated or clustered corticotropes were observed in the proximal pars distalis(PPD). Corticotropes showed a moderate immunoreactivity to synthetic anti‐human adrenocorticotropic hormone 1–24 but a strong immunoreactivity with antiserum to human α‐melanocyte‐stimulating hormone, which so far has not been observed in any other teleosts. Of the two mouse monoclonal antibodies to the human thyrotropin β subunit used, one failed to bind the thyrotropes, while the other stained selectively but very weakly cells in the dorsal‐anterior part of the proximal pars distalis(PPD) indicating that thyrotropes were probably located in this region. Somatotropes were arranged mainly in a multicellular layer bordering the neurohypophysial processes penetrating the PPD, but some were isolated throughout the PPD. The antiserum to rainbow trout Oncorhynchus mykiss gonadotropin I β subunit bound to gonadotropes located in the central and ventral part of the PPD, and along the external periphery of the pars intermedia(PI). The cells reacting to the antiserum to rainbow trout gonadotropin II β subunit largely showed the same distribution as gonadotropes I, but some were also found isolated or in small clusters between somatolactotropes and melanotropes at the interface PI/neurohypophysis (NH) and throughout the PI, as well as intermingled with thyrotropes in the dorsal‐anterior part of the PPD, and with lactotropes and corticotropes in the RPD. These results indicate the presence of two types of both gonadotropins and gonadotropes in P. martensi, but do not exclude some degree of gonadotropin I and gonadotropin II colocalization in the same cells. A distribution of gonadotropes II throughout the adenohypophysis similar to that found in P. martensi has not yet been observed in other teleosts; it suggests the possibility of local interactions between these cells and all the other adenohypophysial cell types. The PI contained somatolactotropes, which were distributed along the neurohypophysial border, and melanotropes which were arranged in clusters mostly located further away from the neural tissue. Melanotropes did not react to PbH and showed positive immunostaining to both anti‐human ACTH 1–24 and anti‐human α‐MSH.
Mitochondrial DNA and allozymes reveal high dispersal abilities and historical movement across drainage boundaries in two species of freshwater fishes from inland rivers in Queensland, Australia
Authors: Hughes J. M. , Hillyer M. J.
Published: June 2006

This study used allozymes and mtDNA variation to test that: 1) populations of two fish species, Nematolosa erebi and Retropinna semoni, in lowland rivers in central Australia were highly connected within drainages, 2) populations in different drainages were highly differentiated and 3) there was evidence of historical connections between two major lowland drainages in inland Australia. Levels of genetic differentiation among populations within drainages were low, but still statistically significant, indicating that populations were not as highly connected as had been predicted. Populations from the Murray–Darling and the Lake Eyre drainages were highly differentiated, indicating no contemporary dispersal across drainage boundaries. Both species showed evidence of historical connections between the two drainage basins, although estimates of the time that these last occurred differed between the two species. Nematolosa erebi populations from the two drainages were estimated to have been separated c. 150 000 years ago, whereas populations of R. semoni, were estimated to have been separated c. 1.5 million years ago.
A case of Grover's disease with syringoma‐like features and leukemia cutis
Authors: García‐Río Irene , Delgado‐Jimenez Yolanda , Aragüés Maximiliano , Fernández‐Herrera Jesus , Fraga Javier , García‐Díez Amaro
Published: June 2006

Leukemia cutis used to be a late manifestation of leukemia. On the other hand, Grover's disease has been described in the setting of cancer.

Case Report:  A patient diagnosed as having a chronic myelomonocytic leukemia presented with lichenoid, slightly infiltrated plaques on the anterior aspect of his thorax and abdomen and papulovesicles on his back. A skin biopsy showed the co‐existence of leukemia cutis, Grover's disease, and syringoma‐like features.

Discussion:  We discuss and comment upon this unusual association.
p63 is a useful marker for cutaneous spindle cell squamous cell carcinoma
Authors: Dotto Jorge E. , Glusac Earl J.
Published: June 2006

Background:  Cutaneous spindle cell squamous cell carcinoma (SCSCC) is a rare variant of SCC. This lesion is sometimes difficult to diagnose based purely on morphologic features. p63 is a member of the p53 gene family that can be identified in epithelial malignancies.

Methods:  Thirteen cases of spindle SCC were stained with p63, CK34βE12, MNF116, vimentin, and S100. Control cases included desmoplastic melanoma (eight cases), atypical fibroxanthoma (AFX) (10 cases), dermatofibrosarcoma protuberans (eight cases), and cutaneous leiomyosarcoma (LMS) (four cases).

Results:  p63 was expressed diffusely in the nuclei of 100% (13/13) of SCSCCs. Of controls, p63 showed focal labeling of two LMS and two AFX. MNF116 and CK34βE12 were positive in 13/13 SCSCCs. Of controls, one LMS was focally positive for MNF116. All SCSCCs and all control cases were positive for vimentin.

Conclusions:  In the given differential diagnosis, p63 appears relatively specific to SCSCC and adds a useful nuclear marker to the available repertoire. The findings also suggest that cytokeratins MNF116 and CK34βE12 may be more useful than standard cytokeratins in labeling SCSCC.
Effects of salinity on the ionic balance and growth of juvenile turbot
Authors: Gaumet F. , Boeuf G. , Severe A. , Le Roux A. , Mayer‐Gostan N.
Published: June 2006

The effects of salinity changes (27, 19 and 10‰) on seawater‐adapted juvenile turbot were studied on their plasma osmolarity and ion concentrations, on oxygen consumption, on gill Na+,K+‐ATPase activity after 3 months and on growth parameters. All plasma concentrations (except chloride) were unchanged, suggesting that fish were well adapted to their environment. Oxygen consumption was significantly decreased in the 19 and 10‰ groups, where fish weighed significantly more 105 days after transfer than fish maintained in sea water. These results, and the fact that apparent food conversion rates were lower in a diluted environment, suggest that on a long term schedule growth conditions could be improved by adaptation to brackish waters (salinities between 10 and 19‰). The effects of transfer from sea water to 27, 19, 10 and 5‰ were also followed during the first 3 weeks. With salinity 10‰ a steady state was reached on day 21 with all plasma values within the same range. The significant differences observed in osmolarity, plasma ion concentrations and Na+,K+‐ATPase activity 3 weeks after transfer of juveniles to 5‰ salinity, compared with transfers in higher salinities, suggest that there is a threshold of acclimation of turbot to a hypotonic environment.
The role of sense organs in the feeding behaviour of juvenile sole and plaice
Authors: Batty R. S. , Hoyt R. D.
Published: June 2006

An infra‐red video recording system was used to observe and compare the feeding activity of juvenile sole and plaice. Experiments in light or dark and chemical ablation of the neuromasts with streptomycin sulphate allowed all or a limited set of senses to be used by the fishes. Both species were able to feed on dead prey when only chemical stimuli were available. Plaice showed a greater dependence on vision for feeding but sole relied principally on chemoreception and mechanoreception. When any one sense was removed plaice became less active whereas sole became more active.
On the life‐history of Atractoscion aequidens, a migratory sciaenid off the east coast of southern Africa
Authors: Griffiths M. H. , Hecht T.
Published: June 2006

East coast geelbek exist as a single stock comprising three distinct age/size structured subpopulations. The subadults (1‐4 years) occur in the SW Cape, South Africa. They feed principally on anchovy Engraulis capensis, which they follow inshore in summer and offshore in winter. The adults (5‐9+ years) undergo a seasonal inshore and longshore migration to Natal where they spawn offshore in spring. During this migration they feed mainly on the pilchard Sardinops sagax, which also move north‐eastwards during this time, facilitated by regional oceanographic conditions. ‘Adolescent’ fish (4/5 years) appear to undergo limited gonadal growth and partially accompany the spawning stock on their migration. It is suggested that the eggs, larvae and early juveniles are transported southwards by the peripheral inshore waters of the Agulhas Current. Juveniles (<2 years) use the SE Cape region as a nursery area for about 1 year, initially feeding on mysids and then switching to anchovy, before moving south‐westwards to join the Subadults in the SW Cape region.
The relationship between a summer fry (0+) abundance index, derived from semi‐quantitative electrofishing, and egg deposition of Atlantic salmon, in the River Bush, Northern Ireland
Authors: Crozier W. W. , Kennedy G. J. A.
Published: June 2006

Atlantic salmon survival in the R. Bush (N. Ireland) from egg to summer 0+ was inversely density‐dependent on egg deposition (P<0.05). A stock‐recruitment relationship derived from egg deposition and summer 0+ abundance index data was compared to that derived from adult and smolt counts based on total trapping. Fitted Ricker curves indicated maximum recruitment at around 2.35 million eggs and 2.46 million eggs for 0+ index and smolt count methods, respectively. Salmon 0+ abundance index data from semi‐quantitative electrofishing could be obtained with relatively little effort, and used to derive whole‐river stock‐recruitment relationships on rivers where only adult count or some other estimator of parental stock is available. The derivation and expression of spawning targets from stock/recruitment relationships is discussed with reference to the R. Bush data.