bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discrete lithofacies discrimination of Jurassic strata using Advanced Spaceborne Thermal Emission and Reflection Radiometer Data, Bighorn Basin, Wyoming, USA
Authors: STRASEN JAMES L. , CHAFETZ HENRY S. , KHAN SHUHAB 
Published: February 2009

AbstractAn investigation of the carbonate sedimentology of the Middle Jurassic strata, Bighorn Basin, North‐central Wyoming, proved to be an ideal test of new spaceborne remote sensing platforms with high spatial and spectral resolution. To evaluate these new tools, it was necessary to: (i) map the occurrence of different lithofacies in at least a part of the area to establish ground truth; (ii) establish the reflectance characteristics of the different lithofacies using portable, on the ground, systems; (iii) produce maps based on spaceborne remote sensing data that discriminate between the lithological types found in the field; and, lastly, (iv) evaluate the discrimination by visiting previously unvisited areas in which these rock types are predicted to occur based upon their remote signatures. Field checking of previously unvisited outcrops demonstrated whether these remote sensing techniques allowed distinction of different lithological outcrops. This investigation determined that the new spaceborne tools could distinguish between outcrops of sparse silty oomicrites from sorted biosparites as small as 10 m by 10 m. In a study area as large as the Bighorn Basin, the ability to identify very small outcrops with a predicted lithology a priori proved to be a major advantage in maximizing field effort.
Autocyclic behaviour of fan deltas: an analogue experimental study
Authors: VAN DIJK MAURITS , POSTMA GEORGE , KLEINHANS MAARTEN G. 
Published: February 2009

AbstractFan deltas are excellent recorders of fan‐building processes because of their high sedimentation rate, particularly in tectonically active settings. Although previous research focuses mainly on allogenic controls, there is clear evidence for autogenically produced storage and release of sediment by flume and numerical modelling that demands further definition of characteristics and significance of autogenically forced facies and stratigraphy. Analogue experiments were performed on fan deltas with constant extrinsic variables (discharge, sediment supply, sea‐level and basin relief) to demonstrate that fan‐delta evolution consists of prominent cyclic alternations of channellized flow and sheet flow. The channellized flow is initiated by slope‐induced scouring and subsequent headward erosion to form a channel that connected with the valley, while the removed sediment is deposited in a rapidly prograding delta lobe. The resulting decrease in channel gradient causes a reduction in flow strength, mouth‐bar formation, flow bifurcation and progressive backfilling of the channel. In the final stage of channel filling, sheet flow coexists for a while with channellized flow (semi‐confined flow), although in cycle 1 this phase of semi‐confined flow was absent. Subsequent autocyclic incisions are very similar in morphology and gradient. However, they erode deeper into the delta plain and, as a result, take more time to backfill. The duration of the semi‐confined flow increases with each subsequent cycle. During the period of sheet flow, the delta plain aggrades up to the ‘critical’ gradient required for the initiation of autocyclic incision. This critical gradient is dependent on the sediment transport capacity, defined by the input conditions. These autogenic cycles of erosion and aggradation confirm earlier findings that storage and release of sediment and associated slope variation play an important role in fan‐delta evolution. The erosional surfaces produced by the autocyclic incisions are well‐preserved by the backfilling process in the deposits of the fan deltas. These erosional surfaces can easily be misinterpreted as climate, sea‐level or tectonically produced bounding surfaces.
Molecular signatures of apomictic and sexual ovules in the Boechera holboellii complex
Authors: Sharbel Timothy F. , Voigt Marie‐Luise , Corral José María , Thiel Thomas , Varshney Alok , Kumlehn Jochen , Vogel Heiko , Rotter Björn 
Published: February 2009

SummaryApomixis, a natural form of asexual seed production in plants, has evolved independently in various taxa, and represents an important potential technology for agriculture. The switch to apomixis is based on de‐regulation of developmental pathways originally leading to sexual seed formation. Hybridization and polyploidy, both typical characteristics of asexual plants and animals, are mechanisms that could trigger de‐regulation. Here we show that up‐regulation of alleles in apomeiotic ovules is mediated by genomic duplication, heterochrony and the residual effects of ancient hybridization in diploid apomicts of the Boechera holboellii complex. Using SuperSAGE, we have identified over 4000 differentially expressed mRNA tags between micro‐dissected ovules from two diploid sexual (Boechera stricta and B. holboellii) and two diploid apomictic (Boechera divaricarpa) accessions. Pairwise sequence comparisons between tags enabled identification of allelic variants of the same loci. Up‐regulated candidate apomeiosis alleles consistently have more than three related alleles, thus demonstrating transcription from duplicated loci. A further 543 alleles were heterochronically expressed between sexual and apomeiotic ovules at developmental stages 2‐II to 2‐IV. Intriguingly, 69 B. holboellii specific alleles were preferentially up‐regulated in apomeiotic ovules, thus showing a remnant‘parent of origin’ effect stemming from the Pleistocene origin of the hybrid B. divaricarpa from taxa related to B. holboellii and B. stricta. These data implicate polyploid gene dosage in the expression of asexual seed formation, and support hypotheses of de‐regulation of the sexual pathway. The observed ‘parent of origin’ effect suggests that the genomic memory of hybridization has somehow been maintained after hundreds, if not thousands, of asexual generations.
Fusarium oxysporum hijacks COI1‐mediated jasmonate signaling to promote disease development in Arabidopsis
Authors: Thatcher Louise F. , Manners John M. , Kazan Kemal 
Published: February 2009

SummaryAlthough defense responses mediated by the plant oxylipin jasmonic acid (JA) are often necessary for resistance against pathogens with necrotrophic lifestyles, in this report we demonstrate that jasmonate signaling mediated through COI1 in Arabidopsis thaliana is responsible for susceptibility to wilt disease caused by the root‐infecting fungal pathogen Fusarium oxysporum. Despite compromised JA‐dependent defense responses, the JA perception mutant coronatine insensitive 1 (coi1), but not JA biosynthesis mutants, exhibited a high level of resistance to wilt disease caused by F. oxysporum. This response was independent from salicylic acid‐dependent defenses, as coi1/NahG plants showed similar disease resistance to coi1 plants. Inoculation of reciprocal grafts made between coi1 and wild‐type plants revealed that coi1‐mediated resistance occurred primarily through the coi1 rootstock tissues. Furthermore, microscopy and quantification of fungal DNA during infection indicated that coi1‐mediated resistance was not associated with reduced fungal penetration and colonization until a late stage of infection, when leaf necrosis was highly developed in wild‐type plants. In contrast to wild‐type leaves, coi1 leaves showed no necrosis following the application of F. oxysporum culture filtrate, and showed reduced expression of senescence‐associated genes during disease development, suggesting that coi1 resistance is most likely achieved through the inhibition of F. oxysporum‐incited lesion development and plant senescence. Together, our results indicate that F. oxysporum hijacks non‐defensive aspects of the JA‐signaling pathway to cause wilt‐disease symptoms that lead to plant death in Arabidopsis.
No decrease in annual risk of tuberculosis infection in endemic area in Cape Town, South Africa
Authors: Kritzinger Fiona E. , Den Boon Saskia , Verver Suzanne , Enarson Donald A. , Lombard Carl J. , Borgdorff Martien W. , Gie Robert P. , Beyers Nulda 
Published: February 2009

SummaryObjective  To estimate the change in annual risk of tuberculosis infection (ARTI) in two neighbouring urban communities of Cape Town, South Africa with an HIV prevalence of approximately 2%, and to compare ARTI with notification rates and treatment outcomes in the tuberculosis (TB) programme.Methods  In 1998–1999 and 2005, tuberculin skin test surveys were conducted to measure the prevalence of Mycobacterium tuberculosis infection and to calculate the ARTI. All 6 to 9‐year‐old children from all primary schools were included in the survey. Notification rates and treatment outcomes were obtained from the TB register.Results  A total of 2067 children participated in the survey from 1998 to 1999 and a total of 1954 in 2005. Based on a tuberculin skin test cut‐off point of 10 mm, the ARTI was 3.7% (3.4–4.0%) in the 1998–1999 survey and 4.1% (3.8–4.5%) in 2005. The notification rate for pulmonary TB increased significantly from 646 per 100 000 in 1998 to 784 per 100 000 in 2002. In Ravensmead, there was no significant change in ARTI [first survey: 3.5% (3.1–3.9%), second survey: 3.2% (2.9–3.6%)], but in Uitsig the ARTI increased significantly from 4.1% (3.6–4.6%) to 5.8% (5.2–6.5%). The difference in ARTI between the two areas was associated with differences in reported case rates and the proportion of previously treated cases.Conclusion  Tuberculosis transmission remains very high in these two communities and control measures to date have failed. Additional measures to control TB are needed.
Malignant glomus tumour in a German shepherd dog
Authors: Park Chun‐Ho , Kozima Daisuke , Tsuzuki Naoto , Ishi Yoshifumi , Oyamada Toshifumi 
Published: February 2009

AbstractA solitary mass, 2.5 cm × 2.5 cm × 2.0 cm in size, was found in the subcutis adjacent to the ischial tuberosity of an 8‐year‐old male German shepherd dog. The excised mass was not encapsulated and the cut surface was solid, grey–white and had multiple red areas suggestive of haemorrhage. Microscopically, the neoplasm was composed of epithelioid cells interspersed with venous vessels of various sizes and irregular bundles of spindle‐shaped tumour cells with mucinous stroma. The nuclei showed anisokaryosis and many mitotic figures were noted. Immunohistochemically, the majority of tumour cells were positive for alpha smooth‐muscle actin and vimentin, but negative for cytokeratin, desmin, S‐100 and factor VIII‐related antigen. Ultrastructurally, the tumour cells contained irregular nuclei, few mitochondria, few rough endoplasmic reticulum, cytoplasmic myofilaments of intermediate density, pinocytotic vesicles and distinct basal lamina. Based on these pathological findings, the diagnosis was malignant glomus tumour.
Consequences of near and far between‐population crosses for offspring fitness in a rare herb
Authors: Raabová J. , Münzbergová Z. , Fischer M. 
Published: February 2009

AbstractCrosses between plants from different populations may result in heterosis or outbreeding depression. However, despite its importance for conservation, little is known about the spatial scale over which these effects may arise. To investigate the consequences of between‐population crosses at two distinct spatial scales, we conducted reciprocal crosses between four populations from two regions in the rare perennial herb Aster amellus. We assessed seed set and offspring fitness in a common garden experiment. Overall, between‐population crosses within regions (10 km) resulted in 8% lower seed set than within‐population crosses, while between‐region crosses (70 km) resulted in 17% higher seed set than within‐population crosses. Moreover, offspring from between‐population crosses produced 18% more flower heads than offspring from within‐population crosses. We conclude that hybridisation between A. amellus plants from different populations did not lead to immediate outbreeding depression and, thus, could represent a valid conservation option to increase genetic diversity. Moreover, our results suggest that the distance between populations affects the outputs of between‐population crosses and therefore needs to be taken into account when promoting gene flow between populations.
PROTECTIVE EFFECTS OF ICARIIN ON COGNITIVE DEFICITS INDUCED BY CHRONIC CEREBRAL HYPOPERFUSION IN RATS
Authors: Xu Rui‐Xia , Wu Qin , Luo Yong , Gong Qi‐Hai , Yu Li‐Mei , Huang Xie‐Nan , Sun An‐Sheng , Shi Jing‐Shan 
Published: February 2009

SUMMARY

Icariin is a major constituent of flavonoids derived from the Chinese medicinal herb Epimedium revicornum Maxim. The aim of the present study was to investigate whether icariin has protective effects on learning ability and memory in a rat model of chronic cerebral hypoperfusion.
Chronic cerebral hypoperfusion was induced by permanent ligation of the common carotid artery in Wistar rats for 4 months. One month after permanent artery occlusion, rats were adminitered icariin at doses of 0, 30, 60 or 120 mg/kg per day, p.o., for 3 months. Neurobehavioural and neurobiochemical parameters were examined to evaluate the effects of icariin on cognitive deficits induced by chronic cerebral hypoperfusion.
The Morris water maze test revealed that learning ability and memory were severely impaired in untreated rats, but were significantly improved in icariin‐treated rats. Icariin treatment also ameliorated chronic cerebral hypoperfusion‐induced oxidative stress in the brain, as evidenced by reduced malondialdehyde formation and maintained superoxide dismutase activity. In addition, the decreased hippocampal levels of acetylcholine, acetylcholinesterase and choline acetyltransferase associated with chronic cerebral hypoperfusion were significantly prevented by icariin treatment.
In conclusion, icariin protects against cognitive deficits induced by chronic cerebral hypoperfusion in rats. These effects appear to be mediated through its anti‐oxidant effects, as well as its effects on the circulatory and cholinergic systems.
HERG‐F463L POTASSIUM CHANNELS LINKED TO LONG QT SYNDROME REDUCE IKr CURRENT BY A TRAFFICKING‐DEFICIENT MECHANISM
Authors: Yang Hai‐Tao , Sun Chao‐Feng , Cui Chang‐Cong , Xue Xiao‐Lin , Zhang Ai‐Feng , Li Hong‐Bing , Wang Dong‐Qi , Shu Juan 
Published: February 2009

SUMMARY

Congenital long QT syndrome (LQTS) is a genetically heterogeneous disease. The aim of the present study was to identify the gene mutation in a Chinese family with LQTS and investigate the functional changes associated with the mutation.
Polymerase chain reaction and DNA sequencing were used to screen for the KCNH2 mutation in the proband. A mutant F463L HERG channel was expressed in HEK293 cells using a lipofectamine method. The IKr current was recorded using the whole‐cell voltage clamp technique. Expression of HERG protein was detected by western blotting and the subcellular location of HERG channels in cell was analysed by confocal microscopy.
The novel heterozygous missense mutation F463L in KCNH2 was detected. We found that the F463L mutation did not lead to any expression of detectable IKr current, which was consistent with western blotting analysis indicating that the F463L mutation only expressed a band at 135 kDa. When coexpressed with wild‐type HERG, F463L HERG exhibited strong dominant‐negative current suppression, resulting in a decrease in IKr current density, and induced a positive shift in the voltage dependence of activation, as well as interference with trafficking of wild‐type channel protein. The processing of the F463L channels was partly corrected in cells incubated in E4031. In addition, confocal microscopy demonstrated that F463L subunits could be inserted into the cell membrane when forming heteromultimeric channels with wild‐type channel subunits.
The results of the present study suggest that the F463L mutation leads to loss of function in HERG through a dominant‐negative effect caused by impaired trafficking of the channel.
MEASUREMENT OF PULMONARY FLOW RESERVE IN HIGHER PRIMATES
Authors: Ilsar Rahn , Chawantanpipat Chirapan , Chan Kim H , Waugh Richard , Hennessy Annemarie , Celermajer David S , Ng Martin KC 
Published: February 2009

SUMMARY

There are currently limited diagnostic methods for assessing the integrity of the pulmonary microvasculature. We hypothesized that a novel, invasively determined physiological index of ‘pulmonary flow reserve’ (PFR = maximal hyperaemic pulmonary blood flow divided by basal pulmonary flow) may facilitate microvascular assessment in the lung. Therefore, we developed a baboon model in which to: (i) validate the use of Doppler flow velocity for PFR assessment; (ii) define the optimal drug and dose regimen for attainment of maximal pulmonary hyperaemia; and (iii) demonstrate the feasibility of measuring PFR in healthy higher primates.
Doppler sensor guidewires were placed in segmental pulmonary arteries of 11 ketamine‐anaesthetized baboons. Vessel diameter, flow velocity and haemodynamics were recorded before and after direct intrapulmonary artery administration of saline, adenosine (50–500 µg/kg per min) and papaverine (3–60 mg), enabling calculation of PFR.
Saline (either bolus injection or infusion) did not alter vessel diameter or flow velocity (P > 0.1), validating local drug administration. Both adenosine and papaverine induced dose‐dependent increases in flow velocity from baseline (from 22.5 ± 2.3 to 32.7 ± 4.8 cm/s for 400–500 µg/kg per min adenosine; and from 23.9 ± 1.1 to 34.6 ± 4.0 cm/s for 24 mg papaverine; both P < 0.0001), without affecting pulmonary artery pressure or vessel diameter (P > 0.3). Healthy primate PFR values were 1.35 ± 0.10 and 1.39 ± 0.10 using 200 µg/kg per min adenosine and 24 mg papaverine, respectively (P > 0.8).
In conclusion, pulmonary flow reserve in higher primates can be assessed using Doppler sensor guidewire and either adenosine or papaverine as microvascular hyperaemic agents. Measurements of PFR may facilitate pulmonary microvascular assessments.
Effectiveness of prokinetic agents against diseases external to the gastrointestinal tract
Authors: Hiyama Toru , Yoshihara Masaharu , Tanaka Shinji , Haruma Ken , Chayama Kazuaki 
Published: February 2009

AbstractProkinetic agents are effective not only for disease of the gastrointestinal (GI) tract but also for those external to the GI tract such as the central nervous system, and the respiratory, urologic, and metabolic organs. This article reviews the effectiveness of prokinetic agents against diseases external to the GI tract. Studies were identified by computerized and manual searches of the available literature. A Medline search was performed (1975–July, 2008) using the following medical subject headings: prokinetic agent, metoclopramide, domperidone, trimebutine, cisapride, itopride, mosapride, tegaserod, and human. The identified diseases for which prokinetic agents may be effective are various: bronchial asthma, chronic cough, hiccup, spontaneous bacterial peritonitis, cholelithiasis, diabetes mellitus, acute migraine, Parkinson's disease, anorexia nervosa, Tourette's disorder, urologic sequelae of spinal cord injury and of radical hysterectomy for cervical cancer, laryngeal dysfunction and so on. These agents are also useful for prevention of aspiration pneumonia during anesthesia, and in tube‐fed patients. Prokinetic agents should be a valuable addition to our currently limited pharmacological armamentarium not only for functional bowel disease, but also for diseases external to the GI tract.
One‐hour fast for water and six‐hour fast for solids prior to endoscopy provides good endoscopic vision and results in minimum patient discomfort
Authors: De Silva Arjuna P , Amarasiri Lakmali , Liyanage Manohari N , Kottachchi Dulani , Dassanayake Anuradha S , De Silva H Janaka 
Published: February 2009

AbstractBackground and Aim:  Current guidelines for upper gastrointestinal endoscopy (UGIE) advise at least 6–8 h fasting for solids and 4‐h fasting for liquids. We aimed to determine whether a 6‐h fast for solids and one‐hour fast for water prior to UGIE gives good endoscopic vision and less patient discomfort.Methods:  128 patients referred for UGIE were given a standard meal 6 h before endoscopy, and then randomized to either nil by mouth for 6 h (group A, n = 65) or allowed to drink water for up to one hour prior to endoscopy (group B, n = 63). Before endoscopy patients were requested to indicate discomfort due to fasting on a visual analog scale. Fluid in the gastric fundus was aspirated, when present, for volume and pH measurements, and endoscopic vision was graded.Results:  53 patients in group A and 43 patients in group B completed the study. Discomfort was significantly lower in group B than group A (P < 0.0001). Endoscopic vision was good in all 53 patients in group A and 40 in group B, and average in 3 patients in group B. Fluid in the gastric fundus was noted in 11 patients in group A and 16 in group B, but there were no significant differences in volume or pH between groups. There were no complications attributable to endoscopy in either group.Conclusions:  A 6‐h fast for solids and a 1‐h fast for water prior to UGIE gives good endoscopic vision, and causes minimum patient discomfort.
Propofol for tracheal intubation in children anesthetized with sevoflurane: a dose–response study
Authors: LERMAN JERROLD , HOULE TIMOTHY T. , MATTHEWS BENJAMIN T. , HOUCK JAMES , BURROWS FREDERICK A. 
Published: February 2009

SummaryBackground:  Tracheal intubation during sevoflurane induction is frequently facilitated with i.v. propofol. We designed a dose–response study to evaluate the intubating conditions, and the incidence and duration of apnea after i.v. propofol in children.Methods/Materials:  Sixty healthy children were randomly assigned to 0, 0.5, 1, 2 or 3 mg·kg−1 i.v. propofol during sevoflurane/nitrous oxide anesthesia. Tracheal intubation was performed approximately 30 s after propofol by an anesthesiologist who was blind to the treatment. The anesthesiologist assessed the responses to laryngoscopy and intubation using a standardized scale. Incidence and duration of apnea after propofol as well as heart rate, and systolic blood pressure before and after laryngoscopy were recorded. Data were analyzed using one‐way and repeated measures anova, the Jonckheere–Terpstra test, and logistic regression, with P < 0.05 accepted.Results:  The laryngoscopy score after 3 mg·kg−1 propofol was less than that after 0 mg·kg−1 (P < 0.01) and 0.5 mg·kg−1 (P < 0.05). Incidence of apnea after propofol 3 mg·kg−1, 8/10, was greater than after 0 mg·kg−1, 3/14 (P < 0.011) and 0.5 mg·kg−1, 3/12 (P < 0.03). Duration of apnea after 3 mg·kg−1 was greater than after 0 and 0.5 mg·kg−1 (P < 0.01). The risk of apnea increased 1.83 fold for each 1 mg·kg−1 dose increase in propofol (P < 0.01). Mean heart rate and systolic pressure decreased with the main effect, time.Conclusion:  During sevoflurane/nitrous oxide anesthesia, propofol 3 mg·kg−1 provides superior intubating conditions with an increased incidence of and prolonged apnea compared with 0 and 0.5 mg·kg−1.