bluuebunny/crossref_metadata_2025_split huggingface dataset:
Taphonomic differentiation ofAcropora palmatafacies in cores from Campeche Bank Reefs, Gulf of México
Authors: Blanchon Paul , Perry Chris T. 
Published: December 2004

AbstractA 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.
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

SummarySome 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

SummaryWe 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

SummaryWe 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

SummaryMany 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

SummaryUsing 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

SummaryMost 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.
Clinical findings among 62 Thais with cholangiocarcinoma
Authors: Wiwanitkit Viroj 
Published: December 2004

SummaryCholangiocarcinoma, 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

SummaryAbout 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

SummaryAnnual 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

SummaryEctoparasitic 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

SummaryThe 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

SummaryA 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

SummaryThe 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.