bluuebunny/crossref_metadata_2025 huggingface dataset:
Late Quaternary shedding of shallow‐marine carbonate along a tropical mixed siliciclastic–carbonate shelf: Great Barrier Reef, Australia
Authors: Dunbar Gavin B. , Dickens Gerald R.
Published: December 2004

Abstract The north‐east Australian margin is the largest modern example of a tropical mixed siliciclastic/carbonate depositional system, with an outer shelf hosting the Great Barrier Reef (GBR) and an inner shelf dominated by fluvially sourced siliciclastic sediment wedges. The long‐term interplay between these sediment components and sea level is recorded in the Queensland Trough, a 1–2 km deep N–S elongate basin situated between the GBR platform and the Queensland Plateau. In this paper, 154 samples from 45 surface grabs and six well‐dated piston cores were analysed for total carbonate content, carbonate mineralogy and Sr concentration to establish spatial and temporal patterns of carbonate accumulation in the Queensland Trough over the last 300 kyr. Surface carbonate contents are lowest on the inner‐shelf (<5%) and in the trough axis (<60%) because of siliciclastic dilution. Carbonate on the shelf is mostly Sr‐rich aragonite and high‐Mg calcite (HMC), whereas that in the basin is mostly low‐Mg calcite. Once normalized to remove the effects of siliciclastic dilution, surface Sr‐rich aragonite and HMC abundances decrease linearly to background levels ≈ 100 km seaward of the shelf edge. Core samples show that, over time, normalized aragonite and Sr abundances are greatest during periods of shelf flooding and lowest when sea level drops below the shelf edge. This is consistent with changes in the production of coral and calcareous algae, and the shedding of their debris from the shelf. Interestingly, normalized HMC concentrations on the slope peak during periods of major transgression, perhaps because of maximum off‐shelf transport from inter‐reef areas or intermediate water dissolution. After accounting for siliciclastic dilution, there are strong similarities in both spatial and temporal patterns of carbonate minerals between slopes and basins of the north‐east Australian margin and those of pure carbonate margins such as the Bahamas. A limited set of basic processes, including the formation and breakdown of carbonate on the shelf, the transport of carbonate off the shelf and eustatic sea level, probably controls carbonate accumulation in slope and basin settings of tropical environments, irrespective of proximal siliciclastic sediment sources.
Taphonomic differentiation ofAcropora palmatafacies in cores from Campeche Bank Reefs, Gulf of México
Authors: Blanchon Paul , Perry Chris T.
Published: December 2004

A common assumption in the geological analysis of modern reefs is that coral community zonation seen on the surface should also be found in cores from the reef interior. Such assumptions not only underestimate the impact of tropical storms on reef facies development, but have been difficult to test because of restrictions imposed by narrow‐diameter cores and poor recovery. That assumption is tested here using large‐diameter cores recovered from a range of common zones across three Campeche Bank reefs. It is found that cores from the reef‐front, crest, flat and rubble‐cay zones are similar in texture and coral composition, making it impossible to recognize coral assemblages that reflect the surface zonation. Taphonomic signatures imparted by variations in encrustation, bioerosion and cementation, however, produce distinct facies and delineate a clear depth zonation. Cores from the reef‐front zone (2–10 m depth) are characterized by sections ofAcropora palmatacobble gravel interspersed with sections of in‐place (but truncated)A. palmatastumps. Upper surfaces of truncated colonies are intensely bioeroded by traces ofEntobiaisp. andGastrochaenolitesisp. and encrusted by mm‐thick crustose corallines before colony regeneration and, therefore, indicate punctuated growth resulting from a hurricane‐induced cycle of destruction and regeneration. Cores from the reef crest/flat (0–2 m depth) are also characterized by sections of hurricane‐derivedA. palmatacobble‐gravels as well as in‐placeA. palmatacolonies. In contrast to the reef front, however, these cobble gravels are encrusted by cm‐thick crusts of intergrown coralline algae, low‐reliefHomotremaand vermetids, bored by traces ofEntobiaisp. andTrypanitesisp. and coated by a dense, peloidal, micrite cement. Cores from the inter‐ to supratidal rubble‐cay zone (+0–5 m) are only composed ofA. palmatacobble gravels and, although clasts show evidence of subtidal encrustation and bioerosion, these always represent processes that occurred before deposition on the cay. Instead, these gravels are distinguished on the basis of their limited bioerosion and marine cements, which exhibit fabrics formed in the intertidal zone. These results confirm that hurricanes have a major influence on facies development in Campeche Bank reefs. Instead of reflecting the surface coral zonation, each facies records a distinctive, depth‐related set of taphonomic processes, which reflect colonization, alteration and stabilization following the production of new substrates by hurricanes.
Phylogenetic relationships of Phyciodes butterfly species (Lepidoptera: Nymphalidae): complex mtDNA variation and species delimitations
Authors: Wahlberg Niklas , Oliveira Rita , Scott James A.
Published: December 2004

Abstract. Mitochondrial DNA variation was studied in the butterfly genus Phyciodes (Lepidoptera: Nymphalidae) by sequencing 1450 bp of the COI gene from 140 individuals of all eleven currently recognized species. The study focused on four species in particular that have been taxonomically difficult for the past century, P. tharos, P. cocyta, P. batesii and P. pulchella. A cladistic analysis of ninety‐eight unique haplotypes showed that Phyciodes forms a monophyletic group with P. graphica as the most basal species. Of the three informal species groups described for Phyciodes, only one (the mylitta‐group) is unambiguously monophyletic. Within the tharos‐group, seven well supported clades were found that correspond to three taxa, P. tharos, P. pulchella and a grade consisting of P. cocyta and P. batesii haplotypes interdigitated with each other. None of the clades is formed exclusively by one species. The patterns of haplotype variation are the result of both retained ancient polymorphism and introgression. Introgression appears to be most common between P. cocyta and P. batesii; however, these two species occur sympatrically and are morphologically and ecologically distinct, suggesting that the level of current introgression does not seem to be enough to threaten their genetic integrity. The results indicate that mitochondrial DNA sequences must be used with great caution in delimiting species, especially when infraspecific samples are few, or introgression seems to be rampant.
HT‐fabrics in a garnet‐bearing quartzite from Western Portugal: geodynamic implications for the Iberian Variscan Belt
Authors: Fernández Francisco J. , Chaminé Helder I. , Fonseca Paulo E. , Munhá José M. , Ribeiro António , Aller Jesus , Fuertes‐Fuentes Mercedes , Borges Frederico S.
Published: December 2004

ABSTRACT The study of a garnet‐bearing quartzite from a major suture zone in Iberia reports an unusual high‐T fabric. Quartz c‐axis patterns were plotted using shaped garnet as reference axis for the finite stretch (X‐axis). The pole figures are characterized by a dominant single maximum around X together with other point maxima along the XY plane (mylonitic foliation). These patterns suggest that dominant  prism slip and subordinated  prism slip operated during quartz plastic deformation in agreement with P–T conditions for syntectonic garnet growth (4–5 kbar and 700 ± 50 °C) and, pre‐dating the well‐known (late) Variscan D1 event (<6 kb and 600 ± 30 °C). The geotectonic framework suggests that the fabrics were formed along the western shear margin of the Ossa‐Morena Zone during the early stages of the Variscan orogeny.
Cyclicities in Triassic platform carbonates: synchronizing radio‐isotopic and orbital clocks
Authors: Mundil Roland , Zühlke Rainer , Bechstädt Thilo , Peterhänsel Arndt , Egenhoff Sven O. , Oberli Felix , Meier Martin , Brack Peter , Rieber Hans
Published: December 2004

ABSTRACT Sedimentary cycles recorded in young sediments are often attributed to fluctuations of the Earth's climate on a 104−106‐year scale which in turn is governed by periodic variations in solar insolation linked to orbital (Milankovitch) parameters. A spectacular example of cyclic stratal patterns in ancient deposits is the Middle Triassic Latemar carbonate platform (W Dolomites, N Italy). Based on spectral analyses from previous studies, a superimposition of precession (∼20 ka) and eccentricity (∼100 ka) controlled sea‐level fluctuations has been suggested to account for the stacking hierarchy at Latemar, with ∼20 ka being assigned to each highest‐order depositional cycle. Zircon U–Pb isotopic ages from volcanic‐ash layers within the cyclic succession, corroborated by biostratigraphic constraints, suggest that the average time interval for every individual cycle is significantly smaller than the shortest Milankovitch period and therefore challenge previously published interpretations relating distinct spectral peaks to the above mentioned hierarchy. However, our new spectral data indicate that cyclicities resembling Milankovitch characteristics might exist, but on an entirely different scale. Our findings show that frequency spectra should only be interpreted in combination with robust age control. They also encourage the search for complementary mechanisms controlling carbonate deposition.
A single nucleotide change within a plant virus satellite RNA alters the host specificity of disease induction
Authors: Sleat† David E. , Palukaitis Peter
Published: December 2004

Some RNA plant viruses contain satellite RNAs which are dependent upon their associated virus for replication and encapsidation. Some cucumber mosaic virus satellite RNAs induce chlorosis on any of several host plants, including either tobacco or tomato. The exchange of sequence domains between cDNA clones of chlorosis‐inducing and non‐pathogenic satellite RNAs delimited the chlorosis domain for both tobacco and tomato plants to the same region. Site‐directed mutagenesis of one nucleotide (149) within this domain changed the host plant specificity for a chlorotic response to satellite RNA infection from tomato to tobacco. Within the chlorosis domain, three conserved nucleotides are either deleted or altered in all satellite RNAs that do not induce chlorosis. Deletion of one of these nucleotides (153) did not affect satellite RNA replication but rendered it non‐pathogenic. Thus, two single nucleotides have been identified which play central roles in those interactions between the virus, its satellite RNA and the host plant, and together result in a specific disease state.
Identification of a mitochondrial transporter for basic amino acids in Arabidopsis thaliana by functional reconstitution into liposomes and complementation in yeast
Authors: Hoyos Mary Elizabeth , Palmieri Luigi , Wertin Timothy , Arrigoni Roberto , Polacco Joseph C. , Palmieri Ferdinando
Published: December 2004

We describe the identification and functional characterization of two Arabidopsis mitochondrial basic amino acid carriers (BAC), AtmBAC1 and AtmBAC2, which are related to the yeast ornithine (Orn) carrier Ort1p, also known as Arg11p. The arg11 mutant requires arginine (Arg) supplementation because it fails to export sufficient ornithine from the mitochondrion to the cytosol where it is converted to arginine. AtmBAC1 and, to a lesser extent, AtmBAC2 partially replaced the function of Ort1p in yeast arg11. The more efficient putative carrier, AtmBAC1, was expressed in E. coli, purified, and reconstituted into phospholipid vesicles, where it transported the basic l‐amino acids arginine, lysine, ornithine and histidine (in order of decreasing affinity). AtmBAC1 recognized l‐histidine whereas both yeast Ort1p and the mammalian ortholog ORNT1p do not. Also different from ORNT1p, AtmBAC1 did not transport citrulline. AtmBAC1 appeared to be more stereospecific than the yeast and mammalian ornithine carriers, exhibiting greater preference for the l‐forms of arginine, lysine and ornithine. By RT‐PCR, both AtmBAC1 and AtmBAC2 transcripts were detected in stems, leaves, flowers, siliques, and seedlings. Expression of AtmBAC1 in seedlings is consistent with its involvement in Arg breakdown in early seedling development, i.e. delivery of Arg to mitochondrial arginase. The Km (0.19 mm) for Arg uptake by AtmBAC1 was close to the value we previously determined for the saturable component of Arg uptake into intact mitochondria from soybean seedling cotyledons.
Antisense inhibition of mitochondrial pyruvate dehydrogenase E1α subunit in anther tapetum causes male sterility
Authors: Yui Rika , Iketani Satoru , Mikami Tetsuo , Kubo Tomohiko
Published: December 2004

We hypothesized that cytoplasmic male sterility (CMS) in sugar beet may be the consequence of mitochondrial dysfunctions affecting normal anther development. To test the hypothesis, we attempted to mimic the sugar beet CMS phenotype by inhibiting the expression of mitochondrial pyruvate dehydrogenase (PDH), which is essential for the operation of the tricarboxylic acid (TCA) cycle. Screening with a cDNA library of sugar beet flower buds allowed the identification of two PDH E1α subunit genes (bvPDH_E1α‐1andbvPDH_E1α‐2).bvPDH_E1α‐1was found to be highly expressed in tap roots, whereasbvPDH_E1α‐2was expressed most abundantly in flower buds. Green fluorescent protein (GFP) fusion of bvPDH_E1α revealed mitochondrial targeting properties. A 300‐bpbvPDH_E1α‐1cDNA sequence (from +620 to +926) was connected to a tapetum‐specific promoter in the antisense orientation and then introduced into tobacco. Antisense expression of bvPDH_E1α‐1 resulted in conspicuously decreased endogenousbvPDH_E1α‐1transcripts and male sterility. The tapetum in the male‐sterile anthers showed swelling or abnormal vacuolation. It is also worth noting that in the sterile anthers, cell organelles, such as elaioplasts, tapetosomes and orbicules were poorly formed and microspores exhibited aberrant exine development. These features are shared by sugar beet CMS. The results thus clearly indicate that inhibition of PDH activity in anther tapetum is sufficient to cause male sterility, a phenocopy of the sugar beet CMS.
Interaction between two cis‐acting elements, ABRE and DRE, in ABA‐dependent expression of Arabidopsis rd29A gene in response to dehydration and high‐salinity stresses
Authors: Narusaka Yoshihiro , Nakashima Kazuo , Shinwari Zabta K. , Sakuma Yoh , Furihata Takashi , Abe Hiroshi , Narusaka Mari , Shinozaki Kazuo , Yamaguchi‐Shinozaki Kazuko
Published: December 2004

Many abiotic stress‐inducible genes contain two cis‐acting elements, namely a dehydration‐responsive element (DRE; TACCGACAT) and an ABA‐responsive element (ABRE; ACGTGG/TC), in their promoter regions. We precisely analyzed the 120 bp promoter region (−174 to −55) of the Arabidopsis rd29A gene whose expression is induced by dehydration, high‐salinity, low‐temperature, and abscisic acid (ABA) treatments and whose 120 bp promoter region contains the DRE, DRE/CRT‐core motif (A/GCCGAC), and ABRE sequences. Deletion and base substitution analyses of this region showed that the DRE‐core motif functions as DRE and that the DRE/DRE‐core motif could be a coupling element of ABRE. Gel mobility shift assays revealed that DRE‐binding proteins (DREB1s/CBFs and DREB2s) bind to both DRE and the DRE‐core motif and that ABRE‐binding proteins (AREBs/ABFs) bind to ABRE in the 120 bp promoter region. In addition, transactivation experiments using Arabidopsis leaf protoplasts showed that DREBs and AREBs cumulatively transactivate the expression of a GUS reporter gene fused to the 120 bp promoter region of rd29A. These results indicate that DRE and ABRE are interdependent in the ABA‐responsive expression of the rd29A gene in response to ABA in Arabidopsis.
The absence of Arabidopsis‐type telomeres in Cestrum and closely related genera Vestia and Sessea (Solanaceae): first evidence from eudicots
Authors: Sykorova Eva , Lim Kar Yoong , Chase Mark W. , Knapp Sandra , Leitch Ilia Judith , Leitch Andrew Rowland , Fajkus Jiri
Published: December 2004

Using slot‐blot and fluorescent in situ hybridization (FISH), we found no evidence for the presence of the Arabidopsis‐type telomeric sequence (TTTAGGG)n at the chromosome termini in any of the Cestrum species we investigated. Probing for the human‐type telomere (TTAGGG)n also revealed no signal. However, polymerase chain reaction experiments indicated that there are short lengths of the sequence TTTAGGG dispersed in the genome but that these sequences are almost certainly too short to act as functional telomeres even if they were at the chromosome termini. An analysis of related genera Vestia and Sessea indicates that they too lack the Arabidopsis‐type telomere, and the sequences were lost in the common ancestor of these genera. We found that the Cestrum species investigated had particularly large mean chromosome sizes. We discuss whether this is a consequence of alternative telomere end maintenance systems.
The Shine‐Dalgarno‐like sequence is a negative regulatory element for translation of tobacco chloroplast rps2 mRNA: an additional mechanism for translational control in chloroplasts
Authors: Plader Wojciech , Sugiura Masahiro
Published: December 2004

Most prokaryotic mRNAs contain within the 5′ untranslated region (UTR), a Shine‐Dalgarno (SD) sequence, which is complementary to the 3′ end of 16S rRNA and serves as a major determinant for correct translational initiation. The tobacco chloroplast rps2 mRNA possesses an SD‐like sequence (GGAG) at a proper position (positions −8 to −5 from the start codon). Using an in vitro translation system from isolated tobacco chloroplasts, the role of this sequence in translation was examined. Unexpectedly, the mutation of the SD‐like element resulted in a large increase in translation. Internal and external deletions within the 5′ UTR revealed that the region from −20 to −5 was involved in the negative regulation of translation. Scanning mutagenesis assays confirmed the above result. Competition assays suggested the existence of a trans‐acting factor(s) involved in translational regulation. In this study, we discuss a possible mechanism for the negative regulation of rps2 mRNA translation.
Used leucodepletion filters as a source of large quantities of DNA suitable for the study of genetic variations in human populations
Authors: Cook M. A. , Jobson S. E. , Atkinson D. C. , Lowe D. P. , Farmer S. L. , Alvi‐Ali W. J. , Smith N. A. , Briggs D. C.
Published: December 2004

summary. A simple technique for developing large control panels with large quantities of DNA suitable for studies in population genetics was established.

Background and objectives Both a lack of suitable controls and insufficient quantities of DNA for repeated analysis of the same control group often hamper the investigation of genetic markers for disease.

Materials and methods Using a waste product from routine blood donation, we describe a simple method that allows the investigator to extract large amounts of DNA.

Results A mean of 1520 µg of DNA per sample was obtained. The DNA obtained remains suitable for polymerase chain reaction and sequencing techniques after 2 years of storage at both 4 °C and −40 °C.

Conclusion This technique allows the development of a large panel of controls with sufficient quantities of genomic DNA for thousands of tests.
Schistosomiasis in two Nile delta villages: an anthropological perspective
Authors: el Katsha Samiha , Watts Susan
Published: December 2004

In the rapidly changing Nile delta villages, applied research for schistosomiasis control requires a holistic view of the social and environmental setting of the disease. An interdisciplinary, participatory study of two delta villages studied human behaviour in relation to disease transmission, knowledge and treatment using the insights and methods of social science, especially anthropology. Through primarily qualitative techniques such as focus group discussions and participant observation, we found that most people who used the canals for domestic, recreational or agricultural activities thought that they had little alternative but to do so, even though they knew of the risk of exposure to schistosomiasis. The knowledge and behaviour of villagers with regard to schistosomiasis affected their utilization of the local provisions for schistosomiasis diagnosis and treatment. Our monitoring of diagnosis and testing for schistosomiasis at a local health centre identified areas which could be upgraded, and we trained health staff to improve their knowledge of schistosomiasis. Our findings reinforce the need for integrated research and implementation strategies, taking into account the knowledge and capabilities of all those involved in schistosomiasis control at the village level, and the fostering of effective communication between villagers, both women and men, and the local staff in rural health centres.
Clinical findings among 62 Thais with cholangiocarcinoma
Authors: Wiwanitkit Viroj
Published: December 2004

Cholangiocarcinoma, a malignancy of the biliary duct system, tends to grow slowly and to infiltrate the walls of the ducts, dissecting along tissue planes and leading to biliary tract obstruction. In a retrospective case review, 62 cases diagnosed with cholangiocarcinoma between January 1997 and December 2001 at the King Chulalongkorn Memorial Hospital in Bangkok were studied. The most commonly observed clinical symptoms and signs were fever (96.8%), abdominal pain (87.1%) and malaise or weakness (83.9%). Fifty‐one of the 62 tumours detected were distal extrahepatic (82.3%), seven perihilar (11.3%) and four intrahepatic (6.7%). There was a significant increase in serum bilirubin and marked elevation of serum alkaline phosphatase. Almost half (45.2%) of the patients presented with other pathological conditions, mostly cholangitis (19 cases) resulting from acute biliary tract obstruction and ascites (13 cases). The pathogens detected were similar in cases of cholangitis alone and cholangiocarcinoma. The major risk factor for this cancer in Thailand is believed to be exposure to liver fluke in insufficiently cooked traditional foods. As it is still endemic in Thailand, continuous prevention and surveillance of this public health problem are necessary.
Hepatic ultrasound in a population with high incidence of invasive amoebiasis: evidence for subclinical, self‐limited amoebic liver abscesses
Authors: Blessmann Joerg , Le Van An , Tannich Egbert
Published: December 2004

About 10% of successfully treated amoebic liver abscesses (ALA) do not completely resolve and can be detected by ultrasound as typical residual liver lesions. The frequency of these residues should be an indicator for the prevalence of ALA in a given population, and may help to solve the question whether non‐clinical, self‐healing ALAs occur. We have performed hepatic ultrasound in 1036 adult individuals living in a high‐risk area for ALA in Central Vietnam and identified typical ALA residual lesions in about 1.2% of the subjects. As expected, these lesions were associated with positive amoeba serology and were found in 11.9% of individuals with a previous ALA history. However, more than 50% of the residues were identified in individuals who had never developed symptoms suspected for ALA and who never received any ALA specific treatment, suggesting that subclinical, self‐limited hepatic amoeba abscesses truly exist.
Long‐term population migration: an important aspect to be considered during mass drug administration for elimination of lymphatic filariasis
Authors: Sunish I. P. , Rajendran R. , Mani T. R. , Gajanana A. , Reuben R. , Satyanarayana K.
Published: December 2004

Annual 2‐drug, single‐dose mass drug administration (MDA) to 80–90% of the eligible population for 4–6 years are pre‐requisites for the successful elimination of lymphatic filariasis (LF) from endemic communities by interruption of transmission and eventual elimination of new infections. In an experimental intervention project on the control of LF in Villupuram district of Tamil Nadu state, India, migration patterns of the villagers were investigated to determine the appropriate timing to implement MDA in order to attain high coverage in a village‐level study. Between January and December 1997, 16 observations took place at 3‐week intervals, following MDA with two drugs viz., diethylcarbamazine and ivermectin, in July–August 1996. The migrants from the village constituted 17–27% at different points of time and both short‐term and long‐term migrating patterns were observed. More villagers were available during the agricultural season (September–January), peaking around mid‐January [83%; significantly higher (P < 0.05)] than during most of the remaining months, including a substantial portion of the migrant population. There is an urgent need to reschedule the yearly MDA in this area to take place in January and to plan mopping up operations by involving local self‐help groups to include migrants (both short‐term and long‐term) in the LF elimination efforts.
Parasitic skin diseases: health care‐seeking in a slum in north‐east Brazil
Authors: Heukelbach Jörg , Van Haeff Evelien , Rump Babette , Wilcke Thomas , Moura Rômulo César Sabóia , Feldmeier Hermann
Published: December 2004

Ectoparasitic diseases are endemic in many poor communities in north‐east Brazil, and heavy infestation is frequent. We conducted two studies to assess disease perception and health care seeking behaviour in relation to parasitic skin diseases and to determine their public health importance. The first study comprised a representative cross‐sectional survey of the population of a slum in north‐east Brazil. Inhabitants were examined for the presence of scabies, tungiasis, pediculosis and cutaneous larva migrans (CLM). The second study assessed health care seeking behaviour related to these ectoparasitoses of patients attending a Primary Health Care Centre (PHCC) adjacent to the slum. Point prevalence rates in the community were: head lice 43.3% (95% CI: 40.5–46.3), tungiasis 33.6% (95% CI: 30.9–36.4), scabies 8.8% (95% CI: 7.3–10.6) and CLM 3.1% (95% CI: 2.2–4.3). Point prevalence rates of patients attending the PHCC were: head lice 38.2% (95% CI: 32.6–44.1), tungiasis 19.1% (95% CI: 14.7–24.1), scabies 18.8% (95% CI: 14.4–23.7) and CLM 2.1% (95% CI: 0.8–4.5). Only 28 of 54 patients with scabies, three of 55 patients with tungiasis, four of six patients with CLM and zero of 110 patients with head lice sought medical assistance. The physicians of the PHCC only diagnosed a parasitic skin disease when it was pointed out by the patient himself. In all cases patients were correctly informed about the ectoparasitosis they carried. The results show that tungiasis and pediculosis, and to a lesser extent scabies and CLM, are hyperendemic but neglected by both population and physicians, and that prevalence rates of tungiasis and scabies at the PHCC do not reflect the true prevalence of these diseases in the community.
Antibiotic therapy in murine filariasis (Litomosoides sigmodontis): comparative effects of doxycycline and rifampicin onWolbachiaand filarial viability
Authors: Volkmann Lars , Fischer Kerstin , Taylor Mark , Hoerauf Achim
Published: December 2004

The symbiosis of filarial nematodes and rickettsialWolbachiaendobacteria has been exploited as a target for antibiotic therapy of filariasis. Depletion ofWolbachiaafter tetracycline treatment results in filarial sterility because of interruption of embryogenesis and inhibits larval development and adult worm viability. The aim of this study was to investigate if antibiotic intervention of BALB/c mice infected with the rodent filariaLitomosoides sigmodontiswith rifampicin or the combination of rifampicin and doxycycline can be used to shorten the treatment period. Both regimens, when given over a period of 14 days initiated with infection, were sufficient to depleteWolbachiaas evidenced by immunohistology and semiquantitative PCR. Worm development and filarial load were significantly reduced in experiments followed up until 63 days p.i. The therapy inhibited embryogenesis and led to filarial sterility. In contrast, treatment with doxycycline alone for 21 days led only to a modest reduction ofWolbachia, filarial growth retardation, worm viability and fertility. In conclusion, the combination of antirickettsial drugs could be used as a suitable tool to explore the minimum duration of therapy required for the depletion ofWolbachiain parasitized hosts subsequent to the onset of patency in human and animal filariasis and the prevention of adverse reactions in human infections.
Polio eradication – the validity of surveillance indicators
Authors: Harris Bernice N , Dürrheim David N , Ogunbanjo Gboyega A
Published: December 2004

A major pre‐requisite for polio‐free certification by the World Health Organization is that the local surveillance system successfully detects one case of non‐polio acute flaccid paralysis (AFP) per 100 000 children below 15 years of age per annum and that no cases of polio occur for three consecutive years. Mpumalanga, a rural province in the northeast of South Africa, implemented an enhanced surveillance system, which consisted of training hospital ICNs to rapidly report and correctly respond to nine infectious disease syndromes, including AFP. Weekly zero reporting is a component of the system. The non‐polio AFP reporting rate per 100 000 children below the age of 15 years increased from 0.56 in 1997 to 0.91 in 1998 after introduction of the enhanced surveillance system, with more than 80% of the units reporting weekly. All units reported weekly from April 1999 to December 2001. Although non‐polio AFP reporting rates were 0.27 (1999), 1.18 (2000) and 0.87 (2001), the 95% binomial exact confidence intervals for all years included 1 per 100 000. A review of paediatric admissions from January 1998 to December 2001 at all hospitals revealed that only five AFP cases had been missed by the enhanced surveillance system. The low international AFP reference rate and attendant variation expected due to chance, particularly in areas with relatively small populations, is an important factor that deserves more attention as we approach global polio eradication.
Living in the paddies: a social science perspective on how inland valley irrigated rice cultivation affects malaria in Northern Côte d'Ivoire
Authors: Plaen Renaud De , Geneau Robert , Teuscher Thomas , Koutoua Amalaman , Marie‐Louise Seka
Published: December 2004

The potential impact of irrigated agriculture on water‐related vector‐borne diseases has been an increasing source of concern for researchers from the bio‐medical sector. While most research on the potential impacts of irrigation on the health of local populations focuses on vector densities, levels of exposures, health services and technologies (prophylaxis, mosquito nets), we argue that it is essential to enlarge the scope of investigation and consider the complex mechanisms by which factors such as agriculture‐generated changes in ecosystems, gender repositioning in the family organization as a result of access to new crops, and production activities combine together in increasing disease risks and producing new scenarios in the management of disease. This paper presents the results of an investigation of how transformations induced on the local society by the intensification of inland valley irrigated rice cultivation influence malaria health care systems and modulate risks to the health of local populations, within well‐defined geographical boundaries in northern Côte d'Ivoire. Our results indicate that socio‐economic transformations and gender repositioning induced, or facilitated, by the intensification of inland valley irrigated rice cultivation lead to a reduction of the capacity of women to manage disease episodes, contributing therefore to increase malaria incidence among farming populations.
Community participation eliminates yaws in Ecuador
Authors: Anselmi Mariella , Moreira Juan‐Martín , Caicedo Cinthia , Guderian Ronald , Tognoni Gianni
Published: December 2004

Yaws is no longer a national and international health priority for intervention, but there is still a negative perception of the disease in the few affected communities. A survey in 1988 in the northern region of Ecuador documented a prevalence of 16.5% of clinical cases and 96.3% of serological cases. A continuous, long‐term community‐based surveillance programme was therefore put in place focusing on yaws as one of the sentinel diseases. The results of this intervention are reported here. In 1993, a second survey showed a reduction in the prevalence of clinical cases to 1.4% and of serological cases to 4.7%. Between 1993 and 1998, no other clinical cases were detected and the serological prevalence in 1998 was 3.5%, corresponding with clinical cases of primary or congenital syphilis, latent yaws under follow‐up, and individuals with low serological titres indicating a ‘serological scar’. These data indicate that yaws has been eliminated. Another important outcome of the intervention is the increased self‐confidence in the communities that health problems can be tackled.
Sexually transmitted infections in a female population in rural north‐east Brazil: prevalence, morbidity and risk factors
Authors: De Lima Soares Valquíria , De Mesquita Ana Maria Torres S. , Cavalcante Fábia Gazzaneo T. , Silva Zenaldo Porfírio , Hora Valéria , Diedrich Thomas , De Carvalho Silva Patrícia , De Melo Poliana Gomes , Dacal Alfredo Raimundo C. , De Carvalho Eduardo Maia Freese , Feldmeier Hermann
Published: December 2004

Objectives To determine the prevalence of major sexually transmitted infections (STIs) and gynaecological morbidity in women of reproductive age living in rural communities in north‐east Brazil and to assess risk factors associated with the presence of STIs.

Methods A total of 341 women (84%) were examined gynaecologically and colposcopically. The gynaecological history was taken by means of a standardized, pre‐tested questionnaire. Cervical smears were obtained and vaginal fluid was collected. Vulvovaginal candidiasis (VC), bacterial vaginosis (BV), trichomoniasis (TV) and syphilis seroreactivity were determined by standard laboratory techniques. Infections with Neisseria gonorrhoeae, Chlamydia trachomatis and human papilloma virus (HPV) were diagnosed by hybrid capture assays using vaginal lavage fluid. Odds ratios (OR) were calculated to assess risk factors associated with STIs.

Results The prevalence of HPV, BV and TV was 26%, 15% and 10%, respectively. VC as well as infections with N. gonorrhoeae and C. trachomatis were detected in 6%; syphilis seroreactivity, in 3%. Multiple infections were very common, and 51% of women had at least one STI. Vaginal discharge, the predominant morbidity (56%), was significantly associated with BV (OR = 6.3; P < 0.001), vulvovaginal itching with VC (OR = 3.5; P < 0.05) and lower abdominal pain with C. trachomatis infection (OR = 2.6; P < 0.04). Colpitis was diagnosed in 27% of women and significantly associated with TV (OR = 3.5%; P < 0.001) and VC (OR = 2.9; P <  0.05). Being unmarried was a significant risk factor for having an STI (OR = 2.4; P < 0.05). Among unmarried women, age (<20 years) was a significant risk factor (OR = 3.3; P = 0.01).

Conclusions The STIs are highly prevalent in this female population in the rural hinterland of north‐east Brazil and associated with considerable morbidity. In view of the expected spread of HIV from the urban centres at the coast to the interior there is an urgent need for providing STI‐related health care and health education for adolescents and women in rural Brazil.
Epidemiology and geography of Schistosoma mansoni in Uganda: implications for planning control
Authors: Kabatereine Narcis B. , Brooker Simon , Tukahebwa Edridah M. , Kazibwe Francis , Onapa Ambrose W.
Published: December 2004

Intestinal schistosomiasis caused by infection with Schistosoma mansoni is a widespread public health problem in Uganda. Although long known to be endemic, its current distribution within the country requires updating of parasitological data to help guide planned control. We report such data collected between 1998 and 2002 from 201 schools and 68 communities across Uganda. In accordance with epidemiological expectation, prevalence and intensity increased with age, peaking at 10–20 years and thereafter declined moderately with age, whereas intensity declined more rapidly with age, and the prevalence of infection in a school was non‐linearly related to the mean intensity of infection. We used geographical information systems to map the distribution of infection and to overlay parasitological data with interpolated environmental surfaces. The derived maps indicate both a widespread occurrence of infection and a marked variability in infection prevalence, with prevalence typically highest near the lakeshore and along large rivers. No transmission occurred at altitudes >1400 m or where total annual rainfall was <900 mm; limits which can help estimate the population at risk of schistosomiasis. The results are discussed in reference to the ecology of infection and provide an epidemiological framework for the design and implementation of control efforts underway in Uganda.
Serological responses to food antigens in normal and atopic dogs, and dogs with gastrointestinal disease
Authors: Foster A. P. , Hotston Moore A. , Knowles T. G. , Cousins P. D. G. , Hall E. J. , Day M. J.
Published: December 2004

In human atopic disease with concurrent food allergy there may be significant increases in serum IgE. Serological methods have not been advocated for suspected food allergy in dogs. The aim of this study was to investigate humeral responses to food antigens in dogs. Serum IgG and IgE antibodies were measured by ELISA against food antigens using polyclonal antidog IgG and IgE reagents. Antigens included beef, chicken, pork, lamb, chicken, turkey, white fish, whole egg, wheat, soybean, barley, rice, maize corn, potato, yeast and cow’s milk. Three groups were used: normal dogs (n = 40 for IgE and n = 91 for IgG), dogs with atopic dermatitis (n = 91), and dogs with four types of gastrointestinal disease (n = 64 for IgE and n = 72 for IgG). The gastrointestinal (GI) subgroups included bacterial overgrowth, inflammatory bowel disease (IBD), food‐responsive and other GI diseases, but statistically significant differences were not detected between them. Statistically significant differences were detected for IgE data for all antigens, and for all except egg and yeast for IgG, using χ2‐test and analysis of variance, respectively. Compared with other groups, atopic dogs had more IgE and dogs with GI disease had more IgG. The relationship of antigen responses for pooled data was analysed using principle component analysis and a cluster plot. Some clustering of variables was apparent for both IgE and IgG. For example for IgG, dog response to chicken and turkey was similar. Using multinomial regression, a predictive model for disease type was formulated with the IgG and IgE response as predictor variables.

 This study was supported, in part, by TLC Pet Allergy Testing Ltd.
The teaching of dermatology in veterinary education in North America (2002)
Authors: Kunkle Gail A. , Nicklin Constance F.
Published: December 2004

AbstractThe purpose of this study was to collect and report the current quantity and content of dermatology taught in the nonclinical and clinical curricula of North American veterinary colleges. This is the first published record of this information and was gathered from 29/30 colleges. Half of the respondents of the questionnaire thought that veterinary students currently receive sufficient didactic dermatology course work. A separate didactic dermatology course is required at 16/29 colleges, which provides a mean of 31.31 instructional units. Twenty‐four of 29 veterinary colleges offer a separate clinical dermatology rotation. Thirteen schools report that students who desire a clinical rotation through dermatology usually attain it. However, it is only required for graduation in seven colleges. This report serves as a tool for veterinary schools assessing their existing curriculum and allows them to compare the education they provide in this specialty with that of other colleges.
An evaluation of four crop : weed competition models using a common data set
Authors: Deen W , Cousens R , Warringa J , Bastiaans L , Carberry P , Rebel K , Riha S , Murphy C , Benjamin L R , Cloughley C , Cussans J , Forcella F , Hunt T. , Jamieson P , Lindquist J , Wang E
Published: December 2004

Summary To date, several crop : weed competition models have been developed. Developers of the various models were invited to compare model performance using a common data set. The data set consisted of wheat and Lolium rigidum grown in monoculture and mixtures under dryland and irrigated conditions. Results from four crop : weed competition models are presented: almanac, apsim, cropsim and intercom. For all models, deviations between observed and predicted values for monoculture wheat were only slightly lower than for wheat grown in competition with L. rigidum, even though the workshop participants had access to monoculture data while parameterizing models. Much of the error in simulating competition outcome was associated with difficulties in accurately simulating growth of individual species. Relatively simple competition algorithms were capable of accounting for the majority of the competition response. Increasing model complexity did not appear to dramatically improve model accuracy. Comparison of specific competition processes, such as radiation interception, was very difficult since the effects of these processes within each model could not be isolated. Algorithms for competition processes need to be modularised in such a way that exchange, evaluation and comparison across models is facilitated.
Transplanting encephalomyocarditis virus‐infected porcine islet cells reverses diabetes in recipient mice but also transmits the virus
Authors: Brewer Laurie , LaRue Rebecca , Hering Bernhard , Brown Corrie , Njenga M. Kariuki
Published: December 2004

Abstract:  Previous studies demonstrated that porcine encephalomyocarditis virus (EMCV) caused acute and persistent infection in the myocardium, central nervous system, and spleen of non‐human primates (cynomolgus macaques); and it productively infected primary human cardiomyocytes, suggesting that the virus may pose a risk in pig‐to‐human transplantation. Recently, transplantation of myocardial and pancreatic tissues from acutely infected pigs transmitted the virus to recipient mice, resulting in acute fatal EMCV disease. Here, we examined whether porcine islet cells (PICs), which are under clinical trial for treatment of type I diabetes in humans, are susceptible to porcine EMCV, and whether EMCV‐infected PICs could function in vivo to reverse diabetes. PICs were infected with EMCV in vitro for 5 h, and resulting insulin production compared with that produced by uninfected PICs. Subsequently, infected PICs were transplanted intra‐abdominally or under the kidney capsule of C57BL/6 mice, and both virus transmission and PIC function analyzed. PICs were highly susceptible to porcine EMCV, resulting in a 1500‐fold increase in production of infectious virus within 5 h of inoculation and cytolysis that destroyed up to 50% of cells within 96 h. However, as long as they were viable, infected PICs produced insulin at levels comparable with uninfected PICs. Intra‐abdominal transplantation of 2000 PICs, infected with one plaque forming unit (pfu) per cell of porcine EMCV, into C57BL/6 mice transmitted the virus resulting in acute fatal EMCV disease characterized by hind limb paresis and paralysis and acute respiratory distress in 40% of recipient mice. More importantly, transplantation of 2500 EMCV‐infected PICs under the kidney capsule of diabetic C57BL/6 mice (glucose level ≥350 mg/dl) reversed diabetes in 83% of recipient mice (glucose level ≤170 mg/dl); however these mice succumbed to acute EMCV disease transmitted by the xenograft 5 days after transplantation. EMCV infection does not appear to affect insulin production by PICs, but infected xenografts can transmit the virus to recipient animals, resulting in severe disease.
Simultaneous Genotyping of Human Platelet Antigens by Hot Start Sequence‐Specific Polymerase Chain Reaction with DNA Polymerase AmpliTaq Gold
Authors: Chen Dong‐Feng , Pastucha Ladislav T. , Chen Hai‐Yan , Kadar Janos G. , Stangel Walter
Published: December 2004

Objectives: Human platelet alloantigen (HPA) typing has potential clinical relevance in a variety of contexts. We can improve methods for HPA genotyping by complementing our knowledge of the DNA sequence polymorphisms of HPA genes and experience with various DNA‐based HPA typing techniques. Methods: A newly available DNA polymerase, AmpliTaq Gold (Perkin Elmer), provided in an inactive state and activated by heat, makes it possible to perform a hot start polymerase chain reaction (PCR) in order to prevent nonspecific amplification during the setup of PCR. To establish a practical procedure for HPA‐1, 2, 3 and 5 genotyping, we applied the AmpliTaq Gold for a hot start PCR and employed 8 pairs of published sequence‐specific primers (SSP). A simple simultaneous genotyping of these 4 HPA systems could be rapidly achieved with high specificity. Results: The HPA gene frequencies observed in 126 randomly selected German blood donors were 0.82 and 0.18 for HPA‐1a and 1b, 0.92 and 0.08 for HPA‐2a and 2b, 0.63 and 0.37 for HPA‐3a and 3b and 0.90 and 0.10 for HPA‐5a and Sb, respectively. Conclusion: Using our hot start PCR‐SSP procedure with AmpliTaq Gold a simple, rapid and reproducible genotyping for HPA‐1, 2, 3 and S systems could be achieved.
Risk Factors and Anti‐HBc Reactivity among First Time Blood Donors
Authors: Molijn M. H. J. , van der Linden J. M. , Ko L. K. , Gorgels J. , Hop W. , van Rhenen D. J.
Published: December 2004

Background and objectives: The usefulness of testing for antibody to hepatitis B core antigen (anti‐HBc) as a surrogate marker for non‐A, non‐B hepatitis can no longer be clearly established in the face of anti‐hepatitis C virus testing. Application of anti‐HBc testing in blood donors for detection of hepatitis B in addition to hepatitis B surface antigen testing (HbsAg) is a matter of debate. Materials and methods: We examined the serology and risk analysis data in a group of first‐time blood donors. In 1.48% of 16,081 donors, anti‐HBc reactivity was found. We invited a study group of 112 donors for extensive interviewing about the risk of blood transmissible diseases, and for serological testing. A control group of 240 first‐time donors was studied as well. Results: In the study group, the age was older (p < 0.001), a history of liver disease was more frequent (p < 0.001), and the donor (p < 0.001) or the donor's partner (p < 0.05) had either stayed longer in an HBV‐endemic area or had been born in one. Combining these with the serological results, we found that strong anti‐HBc reactivity was related to hepatitis B risk factors in HBsAg‐negative donors. Conclusion: Anti‐HBc testing in HbsAg‐negative first‐time donors makes it possible to identify hepatitis B risk factors with a prevalence of 0.02%. Our findings also stress the importance of including the history of the donor's partner(s) in the risk analysis before blood donation.