bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and evaluation of oral controlled-release cilostazol formulation: pharmacokinetics and antithrombotic efficacy in dogs and healthy male Korean participants
Authors: Shin Kwang-Hyun , Yoon Goo , Yoon In-Soo , Park Jin Woo
Published: February 2014

Objectives

To prepare oral controlled-release cilostazol formulations and evaluate their pharmacokinetics and pharmacodynamics in dogs and humans compared with a commercial twice-daily immediate-release formulation (Pletal), thereby showing the potential for the development of an improved once-daily cilostazol formulation.

Methods

Six different controlled-release preparations were formulated using a micronized cilostazol, solubilizer/absorption enhancer and erodible hydrogel. In-vitro drug release profiles were tailored by varying hydrogel viscosity. Pharmacokinetics and pharmacodynamic (antithrombotic) efficacy were evaluated in beagle dog model of arterial thrombosis. Finally, their pharmacokinetics and pharmacodynamics were also evaluated in healthy human volunteers after single and multiple oral administrations.

Key findings

Hydrogel viscosity-dependent sustained drug release profiles were observed with zero-order release kinetics during 8–12 h. In dogs and humans, compared with Pletal, prolonged drug absorption profiles were observed in the two controlled-release formulations studied. In dogs, the controlled-release formulations showed greater antithrombotic efficacy than twice-daily Pletal. In humans, the antithrombotic efficacy of the selected once-daily cilostazol formulation was equivalent to that of twice-daily Pletal after single and multiple administrations.

Conclusions

The prepared oral controlled-release cilostazol formulation may provide prolonged drug absorption and sufficient therapeutic efficacy, potentially serving as an oral once-daily cilostazol formulation to improve patient compliance.
Relationship Between Benign Prostatic Hyperplasia/Lower Urinary Tract Symptoms and Total Serum Testosterone Level in Healthy Middle-Aged Eugonadal Men
Authors: Lee Jun Ho , Kim Yooseok , Park Yeon Won , Lee Dong-Gi
Published: February 2014

Introduction

Scant data are available concerning the relationship between lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH) and total serum testosterone level (TT) in eugonadal state.

Aim

We performed this study to evaluate the relationship between LUTS/BPH and TT in eugonadal men.

Methods

A cross-sectional study was conducted that included a total of 2,308 eugonadal (TT ≥ 3.0 ng/mL) male police officers aged 40–59 years who had participated in a health examination. LUTS/BPH were assessed by prostate-specific antigen level, international prostate symptom score (IPSS), total prostate volume (TPV), maximal flow rate (Qmax), postvoid residual urine volume (PVR), and a full metabolic workup. We then investigated their relationship using the Spearman correlation test, multiple linear regression, and logistic regression analyses.

Main Outcome Measures

Associations of TT with IPSS, Qmax, and PVR.

Results

The median age and TT level were 49.0 years and 5.37 ng/mL, respectively. The TT level showed significant positive correlations with Qmax (r= 0.043,P= 0.048) and a significant negative correlation with PVR (r= −0.050,P= 0.022). No significant correlation was found between TT and TPV or IPSS. However, Qmax and PVR as well as TPV and IPSS did not significantly correlate with TT after adjusting for age and/or metabolic syndrome. On logistic regression, no significant difference was found in surrogate measures of LUTS/BPH (TPV > 30 mL, IPSS > 7, Qmax < 15 mL/second, and PVR > 50 mL) between the highest quartile TT group (median: 7.07 ng/mL) and the lowest quartile group (median: 3.92 ng/mL).

Conclusion

In our study, TT was not clearly correlated with LUTS/BPH in middle-aged eugonadal men.
Facing emotions in narcolepsy with cataplexy: haemodynamic and behavioural responses during emotional stimulation
Authors: de Zambotti Massimiliano , Pizza Fabio , Covassin Naima , Vandi Stefano , Cellini Nicola , Stegagno Luciano , Plazzi Giuseppe
Published: February 2014

Narcolepsy with cataplexy is a complex sleep disorder that affects the modulation of emotions: cataplexy, the key symptom of narcolepsy, is indeed strongly linked with emotions that usually trigger the episodes. Our study aimed to investigate haemodynamic and behavioural responses during emotional stimulation in narco‐cataplexy. Twelve adult drug‐naive narcoleptic patients (five males; age: 33.3 ± 9.4 years) and 12 healthy controls (five males; age: 30.9 ± 9.5 years) were exposed to emotional stimuli (pleasant, unpleasant and neutral pictures). Heart rate, arterial blood pressure and mean cerebral blood flow velocity of the middle cerebral arteries were continuously recorded using photoplethysmography and Doppler ultrasound. Ratings of valence and arousal and coping strategies were scored by the Self‐Assessment Manikin and by questionnaires, respectively. Narcoleptic patients' haemodynamic responses to pictures overlapped with the data obtained from controls: decrease of heart rate and increase of mean cerebral blood flow velocity regardless of pictures' content, increase of systolic blood pressure during the pleasant condition, and relative reduction of heart rate during pleasant and unpleasant conditions. However, when compared with controls, narcoleptic patients reported lower arousal scores during the pleasant and neutral stimulation, and lower valence scores during the pleasant condition, respectively, and also a lower score at the ‘focus on and venting of emotions’ dimensions of coping. Our results suggested that adult narcoleptic patients, compared with healthy controls, inhibited their emotion‐expressive behaviour to emotional stimulation, and that may be related to the development of adaptive cognitive strategies to face emotions avoiding cataplexy.
Qualitative and Quantitative Contrast‐Enhanced Ultrasonographic Assessment of Cerulein‐Induced Acute Pancreatitis in Dogs
Authors: Lim S.Y. , Nakamura K. , Morishita K. , Sasaki N. , Murakami M. , Osuga T. , Ohta H. , Yamasaki M. , Takiguchi M.
Published: February 2014

Background

Acute pancreatitis (AP) is the most common disease of the canine exocrine pancreas, and accurate noninvasive diagnosis is challenging.

Hypothesis/Objectives

To determine the feasibility of using quantitative contrast‐enhanced ultrasonography (CEUS) to detect pancreatic perfusional changes in cerulein‐inducedAPin dogs.

Animals

Six adult female Beagles.

Methods

Each dog received 2 hours ofIVinfusion with 7.5 μg/kg/h of cerulein diluted in saline. As control, all dogs received 2 hours ofIVinfusion of saline 2 weeks before cerulein infusion.CEUSof the pancreas and duodenum were performed before (0 hour), and at 2, 4, 6, and 12 hours after saline and cerulein infusion. Time‐intensity curves were created from regions of interest in the pancreas and duodenum. Five perfusional parameters were measured for statistical analysis: time to initial up‐slope, peak time, time to wash‐out, peak intensity (PI), and area under the curve (AUC).

Results

In cerulein‐inducedAP, pancreaticPIincreased at 2 and 4 hours when compared to 0 hour, and at 2, 4, and 6 hours when compared to control.AUCincreased at 4 hours when compared to 0 hour, and at 2 and 4 hours when compared to control. Time to wash‐out was prolonged at 4 hours when compared to control. For saline control, peak time was faster at 2 hours when compared to 0 hour.

Conclusions and Clinical Importance

CEUSparametersPIandAUCcan provide useful information in differentiating acute pancreatitis from normal pancreas. Cerulein‐inducedAPwas characterized by prolonged hyperechoic enhancement onCEUS.
DEA1 Expression on Dog Erythrocytes Analyzed by Immunochromatographic and Flow Cytometric Techniques
Authors: Acierno M.M. , Raj K. , Giger U.
Published: February 2014

Background

The Dog erythrocyte antigen (DEA) 1 blood group system was thought to contain typesDEA1.1 and 1.2 (and possibly 1.3 [A3]). However,DEA1.2+ dogs are very rare and newer typing methods reveal varying degrees ofDEA1 positivity.

Objectives

To assess if variation inDEA1 positivity is because of quantitative differences in surface antigen expression. To determine expression patterns in dogs over time and effects of blood storage (4°C). To evaluateDEA1.2+ samples byDEA1 typing methods.

Animals

Anticoagulated blood samples from 66 dogs in a research colony and from a hospital, and 9 previously typedDEA1.2+ dogs from an animal blood bank.

Methods

Research study: Samples were analyzed by flow cytometry and immunochromatographic strip using a monoclonal anti‐DEA1 antibody.

Results

Twenty dogs wereDEA1−, whereas 46 dogs were weakly to stronglyDEA1+. Antigen quantification revealed excellent correlation between strip and flow cytometry (r = 0.929). Both methods reclassifiedDEA1.2+ samples as weakly to moderatelyDEA1+, but they were not retyped with the polyclonal anti‐DEA1.1/1.X antibodies. Dogs and blood samples retained their relativeDEA1 antigen densities over time.

Conclusions and Clinical Importance

The blood group systemDEA1 is a continuum from negative to strongly positive antigen expression. Previously typedDEA1.2+ appears to beDEA1+. These findings further the understanding of theDEA1 system and suggest that all alleles within theDEA1 system have a similarly based epitope recognized by the monoclonal antibody.
Evaluation of Quality of Life in Dogs with Idiopathic Epilepsy
Authors: Wessmann A. , Volk H.A. , Parkin T. , Ortega M. , Anderson T.J.
Published: February 2014

Background

The impact of epilepsy and its treatment on the quality of life (QoL) is considered an important part of treatment supervision in human epilepsy.

Objectives

To develop a list of key questions evaluating QoL in dogs with idiopathic epilepsy (IE) and their carers.

Animals

One hundred fifty‐nine dogs with IE.

Methods

Cross‐sectional study. An online project questionnaire was developed containing 90 QoL‐associated questions that were initially allocated to 14 themes representing specific areas associated with the treatment and care of an epileptic dog. Principal component analysis was applied with the aim of refining the questionnaire to the least number of questions representing useful themes without loss of descriptive value. Carers were recruited by paper mail, primary practices, and canine epilepsy websites. Data were acquired from January to November 2011.

Results

Principal component analysis removed 54 questions, leaving 7 themes with 36 questions with a minimum Cronbach's alpha value of 0.7 indicating a good internal consistency: “Seizure severity and frequency”, “Adverse effects of antiepileptic drug (AED)”, “Restrictions on the carer's life”, “Frustrations over caring for a dog with IE”, “Carer distaste of AED adverse effects”, “Carer anxiety around the seizure event”, “Perceptions on rectal diazepam use”.

Conclusions and Clinical Importance

Principal component analysis successfully reduced the number of questions without loss in descriptive value. The remaining questions correlate well with each other in capturing valuable details about aspects of QoL and represent valuable key questions (EpiQoL) in the assessment of QoL for the carers of dogs with IE.
Predator community structure and trophic linkage strength to a focal prey
Authors: Lundgren Jonathan G. , Fergen Janet K.
Published: February 2014

Predator abundance and community structure can affect the suppression of lower trophic levels, although studies of these interactions under field conditions are relatively few. We investigated how the frequency of consumption (measured using PCR‐based gut content analysis) is affected by predator abundance, community diversity and evenness under realistic conditions. Soil arthropod communities in sixteen maize fields were measured (number of predators, diversity [Shannon H] and evenness [J]), and predator guts were searched for DNA of the focal subterranean herbivore, the corn rootworm (Diabrotica virgifera). Predator abundance and diversity were positively correlated with trophic linkage strength (the proportion positive for rootworm DNA), although the latter characteristic was not significantly so. The diversity and evenness of the predator community with chewing mouthparts were strongly correlated with their linkage strength to rootworms, whereas the linkage strength of fluid‐feeding predators was unaffected by their community characteristics. Within this community, chewing predators are more affected by the rootworm's hemolymph defence. This research clearly shows that predator abundance and diversity influence the strength of a community's trophic linkage to a focal pest and that these community characteristics may be particularly important for less palatable or protected prey species. We also make the case for conserving diverse and abundant predator communities within agroecosystems as a form of pest management.
BrlR from Pseudomonas aeruginosa is a c‐di‐GMP‐responsive transcription factor
Authors: Chambers Jacob R. , Liao Julie , Schurr Michael J. , Sauer Karin
Published: February 2014

The transcriptional regulator BrlR is a member of the MerR family of multidrug transport activators that contributes to the high‐level drug tolerance of Pseudomonas aeruginosa biofilms. While MerR regulators are known to activate both the expression of multidrug efflux pump genes and their own transcription upon inducer binding, little is known about BrlR activation. We demonstrate using promoter reporter strains, in vivo and in vitro DNA‐binding assays combined with 5′RACE, that BrlR binds to its own promoter, likely via a MerR‐like palindromic sequence. Unlike known MerR multidrug transport activators, BrlR and brlR expression are not activated by multidrug transporter substrates. Instead, BrlR–DNA binding was enhanced by the secondary messenger c‐di‐GMP. In addition to enhanced BrlR–DNA binding, c‐di‐GMP levels contributed to PbrlR promoter activity in initial attached cells with elevated c‐di‐GMP levels correlating with increased expression of brlR. While not harbouring amino acid motifs resembling previously defined c‐di‐GMP‐binding domains, BrlR was found to bind c‐di‐GMP in vitro at a ratio of one c‐di‐GMP per two BrlR. Cross‐linking assays confirmed dimer formation to be enhanced in the presence of elevated c‐di‐GMP levels. Our findings demonstrate BrlR to be an unusual MerR‐family member in that BrlR function and expression require the secondary messenger c‐di‐GMP.
An evolutionarily conserved RNase‐based mechanism for repression of transcriptional positive autoregulation
Authors: Wurtmann Elisabeth J. , Ratushny Alexander V. , Pan Min , Beer Karlyn D. , Aitchison John D. , Baliga Nitin S.
Published: February 2014

It is known that environmental context influences the degree of regulation at the transcriptional and post‐transcriptional levels. However, the principles governing the differential usage and interplay of regulation at these two levels are not clear. Here, we show that the integration of transcriptional and post‐transcriptional regulatory mechanisms in a characteristic network motif drives efficient environment‐dependent state transitions. Through phenotypic screening, systems analysis, and rigorous experimental validation, we discovered an RNase (VNG2099C) in Halobacterium salinarum that is transcriptionally co‐regulated with genes of the aerobic physiologic state but acts on transcripts of the anaerobic state. Through modelling and experimentation we show that this arrangement generates an efficient state‐transition switch, within which RNase‐repression of a transcriptional positive autoregulation (RPAR) loop is critical for shutting down ATP‐consuming active potassium uptake to conserve energy required for salinity adaptation under aerobic, high potassium, or dark conditions. Subsequently, we discovered that many Escherichia coli operons with energy‐associated functions are also putatively controlled by RPAR indicating that this network motif may have evolved independently in phylogenetically distant organisms. Thus, our data suggest that interplay of transcriptional and post‐transcriptional regulation in the RPAR motif is a generalized principle for efficient environment‐dependent state transitions across prokaryotes.
Elucidation of the structures of all members of the Avsunviroidae family
Authors: Giguère Tamara , Adkar‐Purushothama Charith Raj , Bolduc François , Perreault Jean‐Pierre
Published: February 2014

Viroids are small single‐stranded RNA pathogens which cause significant damage to plants. As their nucleic acids do not encode for any proteins, they are dependant solely on their structure for their propagation. The elucidation of the secondary structures of viroids has been limited because of the exhaustive and time‐consuming nature of classic approaches. Here, the method of high‐throughput selective 2′‐hydroxyl acylation analysed by primer extension (hSHAPE) has been adapted to probe the viroid structure. The data obtained using this method were then used as input for computer‐assisted structure prediction using RNAstructure software in order to determine the secondary structures of the RNA strands of both (+) and (–) polarities of all Avsunviroidae members, one of the two families of viroids. The resolution of the structures of all of the members of the family provides a global view of the complexity of these RNAs. The structural differences between the two polarities, and any plausible tertiary interactions, were also analysed. Interestingly, the structures of the (+) and (–) strands were found to be different for each viroid species. The structures of the recently isolated grapevine hammerhead viroid‐like RNA strands were also solved. This species shares several structural features with the Avsunviroidae family, although its infectious potential remains to be determined. To our knowledge, this article represents the first report of the structural elucidation of a complete family of viroids.
Virulence of the maize smut Ustilago maydis is shaped by organ‐specific effectors
Authors: Schilling Lena , Matei Alexandra , Redkar Amey , Walbot Virginia , Doehlemann Gunther
Published: February 2014

With the exception of Ustilago maydis, smut fungi infecting monocotyledonous hosts systemically colonize infected plants and cause symptoms exclusively in the inflorescences. Ustilago maydis infects primordia of all aerial organs of maize (Zea mays L.) and results in the formation of large plant tumours. Previously, we have found that U. maydis infection of seedling leaves, adult leaves and tassels causes organ‐specific transcriptional changes in both the pathogen and the host. Of particular interest, U. maydis genes encoding secreted proteins are differentially expressed depending on the colonized maize organ. Therefore, we hypothesized that the fungus secretes virulence‐related proteins (effectors) that act in an organ‐specific manner. Here, we present the identification and functional characterization of 20 presumptive organ‐specific U. maydis effector genes. Ustilago maydis deletion strains for these genes were generated and tested for infectivity of maize seedling leaves and tassels. This approach identified 11 effector genes required for the full virulence of U. maydis. In nine cases, virulence was only affected in one of the tested plant organs. These results demonstrate that individual fungal effector proteins contribute to fungal virulence in an organ‐specific manner.
Disseminated histoplasmosis in HIV‐infected patients: determinants of relapse and mortality in a north‐eastern area of Brazil
Authors: Damasceno Lisandra Serra , Ramos Alberto Novaes , Alencar Carlos Henrique , Gonçalves Maria Vânia Freitas , de Mesquita Jacó Ricarte Lima , Soares Anne Taumaturgo Dias , Coutinho Anna Gisele Nunes , Dantas Carolina Cavalcante , Leitão Terezinha do Menino Jesus Silva
Published: February 2014

Many relapses and deaths resulting from disseminated histoplasmosis (DH) in acquired immunodeficiency syndrome (AIDS) patients have been observed in an endemic area in north‐eastern Brazil. The objective of this study was to evaluate the risk factors associated with the clinical outcomes of DH/AIDS coinfection in patients from the state of Ceará, Brazil. A retrospective cohort of AIDS patients, after their hospital discharge due to first DH episode in the period 2002–2008, was followed until December 31, 2010, to investigate the factors associated with relapse and mortality. A total of 145 patients were evaluated in the study. Thirty patients (23.3%) relapsed and the overall mortality was 30.2%. The following variables were significantly (P < 0.05) associated with relapse and overall mortality (univariate analysis): non‐adherence to highly active antiretroviral therapy (HAART), irregular use of an antifungal, non‐recovery of the CD4+ count and having AIDS before DH; histoplasmosis relapse was also significantly associated with mortality. In the multivariate analysis, non‐adherence to HAART was the independent risk factor that was associated with both relapse (Adj OR = 6.28) and overall mortality (Adj OR = 8.03); efavirenz usage was discovered to be significant only for the overall mortality rate (Adj OR = 4.50). Adherence to HAART was the most important variable that influenced the outcomes in this specific population.
Heterogeneity of mucosal mast cell infiltration in subgroups of patients with esophageal chest pain
Authors: Lee H. , Chung H. , Park J. C. , Shin S. K. , lee S. K. , Lee Y. C.
Published: February 2014

Background

Although there is growing evidence that an increase in mucosal mast cells (MMCs) in the small and large intestine is associated with visceral hypersensitivity, few studies have evaluated MMCs in humans with esophageal symptoms. The aim of this study was to investigate esophageal MMC distribution in patients with non‐cardiac chest pain (NCCP) and to examine the association between the number of gut MMCs and other functional gastrointestinal disorders.

Methods

Forty‐two consecutive NCCP patients and 10 healthy controls completed a questionnaire for bowel symptoms, chest pain intensity score, and psychologic depression. Esophageal, duodenal, and rectal MMCs were identified immunohistochemically and quantified by image analysis.

Key Results

Numbers of MMCs were significantly higher in NCCP patients vs healthy controls (11.8 ± 5.6 vs 7.6 ± 3.7 MMCs/high‐power field, p = 0.026). In comparison of subgroups classified by 24‐h impedance–pH monitoring, esophageal MMC counts were highest in the hypersensitive esophagus group (p < 0.01) and were also significantly increased in the functional chest pain group (p < 0.05). A positive correlation between esophageal and duodenal MMC counts was observed in patients with functional dyspepsia (FD; Spearman ρ = 0.604, p = 0.037). In particular, patients with clinical overlap with irritable bowel syndrome showed a strong positive correlation between esophageal and rectal MMC numbers (Spearman ρ = 0.857, p = 0.010).

Conclusions & Inferences

Among NCCP patients, increased MMC infiltration occurs in subgroups with hypersensitive esophagus and functional chest pain. In subpopulations with overlap with FD or irritable bowel syndrome, esophageal MMC counts demonstrated significant positive correlations with duodenal or rectal MMC counts.
How copper traverses cellular membranes through the mammalian copper transporter 1, Ctr1
Authors: Öhrvik Helena , Thiele Dennis J.
Published: February 2014

The copper transporter 1, Ctr1, is part of a major pathway for cellular copper (Cu) uptake in the intestinal epithelium, in hepatic and cardiac tissue, and likely in many other mammalian cells and tissues. Here, we summarize what is currently known about how extracellular Cu travels across the plasma membrane to enter the cytoplasm for intracellular distribution and for use by proteins and enzymes, the physiological roles of Ctr1, and its regulation. As a critical Cu importer, Ctr1 occupies a strategic position to exert a strong modifying influence on diseases and pathophysiological states caused by imbalances in Cu homeostasis. A more thorough understanding of the mechanisms that regulate Ctr1 abundance, trafficking, and function will provide new insights and opportunities for disease therapies.
The tommotiid Kelanella and associated fauna from the early Cambrian of southern Montagne Noire (France): implications for camenellan phylogeny
Authors: Devaere Léa , Clausen Sébastien , Monceret Eric , Vizcaïno Daniel , Vachard Daniel , Genge Marie C.
Published: February 2014

A carbonate bed of the Pardailhan Formation, early Cambrian, southern Montagne Noire (southern France), provided microfossils such as Hyolithellus sp., Torellella cf. mutila and Torellella sp. along with numerous disarticulated pieces of composite skeletons such as valves of the brachiopod Eoobolus priscus and of the bradoriid Monceretia erisylvia, and chancelloriid sclerites (Chancelloria sp.). The assemblage also furnished a rich set of sclerites from the tommotiid Kelanella altaica. Five morphological variations of the latter have been identified. The presence of concentric ribs formed by distal inflation of selected shell laminae in Kelanella supports its assignment to the camenellans. More particularly, the presence of transverse structures within the internal cavity (septa) of Kelanella suggests a close relationship with the Lapworthellidae. However, the latter differ from Kelanella by the continuous morphological variation along their scleritome which is also composed of simple conical elements with uniform ornamentation. Several forms of Kelanella are similar to mitral and sellate sclerites of Camenella, whereas some other forms are comparable to Kennardia. The new material suggests that Kelanella occupies a transitional position between Lapworthellidae and the grouping of Tommotiidae and Kennardiidae. Such a phylogenetic position also implies that the number of sclerite morphotypes tends to decrease within the camenellan scleritome during evolution.
Elevated CO2 alters the feeding behaviour of the pea aphid by modifying the physical and chemical resistance of Medicago truncatula
Authors: GUO HUIJUAN , SUN YUCHENG , LI YUEFEI , LIU XIANGHUI , WANG PINGYAN , ZHU‐SALZMAN KEYAN , GE FENG
Published: February 2014

Elevated CO2 compromises the resistance of leguminous plants against chewing insects, but little is known about whether elevated CO2 modifies the resistance against phloem‐sucking insects or whether it has contrasting effects on the resistance of legumes that differ in biological nitrogen fixation. We tested the hypothesis that the physical and chemical resistance against aphids would be increased in Jemalong (a wild type of Medicago truncatula) but would be decreased in dnf1 (a mutant without biological nitrogen fixation) by elevated CO2. The non‐glandular and glandular trichome density of Jemalong plants increased under elevated CO2, resulting in prolonged aphid probing. In contrast, dnf1 plants tended to decrease foliar trichome density under elevated CO2, resulting in less surface and epidermal resistance to aphids. Elevated CO2 enhanced the ineffective salicylic acid‐dependent defence pathway but decreased the effective jasmonic acid/ethylene‐dependent defence pathway in aphid‐infested Jemalong plants. Therefore, aphid probing time decreased and the duration of phloem sap ingestion increased on Jemalong under elevated CO2, which, in turn, increased aphid growth rate. Overall, our results suggest that elevated CO2 decreases the chemical resistance of wild‐type M. truncatula against aphids, and that the host's biological nitrogen fixation ability is central to this effect.
Water deficit induces chlorophyll degradation via the ‘PAO/phyllobilin’ pathway in leaves of homoio‐ (Craterostigma pumilum) and poikilochlorophyllous (Xerophyta viscosa) resurrection plants
Authors: CHRIST BASTIEN , EGERT AURÉLIE , SÜSSENBACHER IRIS , KRÄUTLER BERNHARD , BARTELS DOROTHEA , PETERS SHAUN , HÖRTENSTEINER STEFAN
Published: February 2014

Angiosperm resurrection plants exhibit poikilo‐ or homoiochlorophylly as a response to water deficit. Both strategies are generally considered as effective mechanisms to reduce oxidative stress associated with photosynthetic activity under water deficiency. The mechanism of water deficit‐induced chlorophyll (Chl) degradation in resurrection plants is unknown but has previously been suggested to occur as a result of non‐enzymatic photooxidation. We investigated Chl degradation during dehydration in both poikilochlorophyllous (Xerophyta viscosa) and homoiochlorophyllous (Craterostigma pumilum) species. We demonstrate an increase in the abundance of PHEOPHORBIDE a OXYGENASE (PAO), a key enzyme of Chl breakdown, together with an accumulation of phyllobilins, that is, products of PAO‐dependent Chl breakdown, in both species. Phyllobilins and PAO levels diminished again in leaves from rehydrated plants. We conclude that water deficit‐induced poikilochlorophylly occurs via the well‐characterized PAO/phyllobilin pathway of Chl breakdown and that this mechanism also appears conserved in a resurrection species displaying homoiochlorophylly. The roles of the PAO/phyllobilin pathway during different plant developmental processes that involve Chl breakdown, such as leaf senescence and desiccation, fruit ripening and seed maturation, are discussed.
The biology of hyperpigmentation syndromes
Authors: Speeckaert Reinhart , Van Gele Mireille , Speeckaert Marijn M. , Lambert Jo , van Geel Nanja
Published: February 2014

Hyperpigmentation is a key feature in a variety of inherited and acquired syndromes. Nonetheless, determining the exact diagnosis only on the clinical phenotype can be challenging, and a detailed search for associated symptoms is often of crucial importance. As pigmentation pathways are regulated by complex signaling transduction cascades (e.g. MSH/cAMP, KIT signaling pathways), the underlying defects leading to elevated melanin production are numerous. With regard to treatment, limited therapeutic options exist, each with specific side effects. In acquired hyperpigmentation, the melanin deposition may, however, be reversible after adequate therapy of the underlying disorder or even disappear spontaneously. In this review, we provide an overview of the biology of hyperpigmentation syndromes classified according to the main underlying defect that deregulates physiological melanogenesis. The identification of novel genes or key players involved in hyperpigmentary disorders is becoming increasingly important in view of the development of safer and more efficient treatments.
The influence of nuptial feeding and sperm transfer on the immunological cost of reproduction in the ground cricket Allonemobius socius
Authors: Fedorka Kenneth M. , Sevgili Hasan
Published: February 2014

Mating is often accompanied by decreased female immune function across numerous animals systems, suggesting that immune suppression is a widespread reproductive cost. However, the trade‐off between immunity and reproduction can be minimized when females have access to abundant nutrient resources. This observation suggests that the nuptial gifts provided by males in many insect systems may help to offset the common immunological cost to reproduction. In the present study, this hypothesis is tested in the ground cricket Allonemobius socius (Scudder), whose females receive a sizeable haemolymph‐based gift. Accordingly, male gift donation is controlled by covering the tibial spur (the source of the gift) of randomly chosen males with clear nail polish. The influence of sperm transfer on female immunity is disentangled from that of the nuptial gift by also examining females who fail to receive sperm during mating (spermatophore transfer has a 40% failure rate in virgin males). It is predicted that females who receive a nuptial gift will exhibit superior immune function compared with those who receive no gift. The results show that sperm transfer reduces female immune function, which is an expected immunological cost of reproduction. By contrast to the prediction, nuptial gifts do not minimize the immunological cost of reproduction in this system. Unexpectedly, the receipt of a gift appears to decrease female immune function independent of sperm transfer. The findings suggest that the nuptial gift, similar to sperm, signals the female to begin her reproductive investment, causing limited resources to be reallocated from immune function.
Range‐Based Versus Automated Markerless Image‐Based Techniques For Rock Art Documentation
Authors: Lerma José L. , Navarro Santiago , Seguí Ana E. , Cabrelles Miriam
Published: February 2014

Nowadays there is a huge proliferation of fully automatic image‐based solutions producing either three‐dimensional (3D) point clouds or 3D models. However, the reliability of the output is not usually reported and clarified. This paper presents a comparison of the 3D modelling results achieved on two rock art shelters at separate archaeological sites using a high‐resolution digital camera. The 3D point clouds were produced using automatic image‐based photogrammetric and computer vision software running either locally (FOTOGIFLE and VisualSFM) or through a web‐based reconstruction service (Autodesk 123D Catch). The first two automatic approaches are compared with a manual bundle block adjustment. Dense image matching was undertaken to densify the point clouds prior to 3D modelling. The derived 3D models are compared with a time‐of‐flight laser scanning dataset that was used as ground truth. Statistical analysis shows significant metric differences on the digital surface models for the different solutions.
The genetic characterization of Xanthomonas arboricola pv. juglandis, the causal agent of walnut blight in Poland
Authors: Kałużna M. , Pulawska J. , Waleron M. , Sobiczewski P.
Published: February 2014

Leaves and fruits of walnut trees exhibiting symptoms of bacterial blight were collected from six locations in Poland. Isolations on agar media resulted in 18 bacterial isolates with colony morphology resembling that of the Xanthomonas genus. PCR using X1 and X2 primers specific for Xanthomonas confirmed that all isolates belonged to this genus. In pathogenicity tests on unripe walnut fruits, all isolates caused typical black necrotic lesions covering almost the entire pericarp. Results of selected phenotypic tests indicated that characteristics of all isolates were the same as described for the type strain of Xanthomonas arboricola pv. juglandis. Genetic analyses (PCR MP, ERIC‐, BOX‐PCR and MLSA) showed similarities between the studied isolates and the reference strain of X. arboricola pv. juglandis CFBP 7179 originating from France. However, reference strains I‐391 from Portugal and LMG 746 from the UK were different. MLSA analysis of partial sequences of the fyuA, gyrB and rpoD genes of studied isolates and respective sequences from GenBank of pathotype strains of other pathovars of X. arboricola showed that the X. arboricola pv. juglandis isolates consisted of different phylogenetic lineages. An incongruence among MLSA gene phylogenies and traces of intergenic recombination events were proved. These data suggest that the sequence analysis of several housekeeping genes is necessary for proper identification of X. arboricola pathovars.
Early senescence of the oldest leaves of Fe‐deficient barley plants may contribute to phytosiderophore release from the roots
Authors: Higuchi Kyoko , Iwase Jun , Tsukiori Yoshifumi , Nakura Daiki , Kobayashi Nahoko , Ohashi Hidenori , Saito Akihiro , Miwa Eitaro
Published: February 2014

Barley (Hordeum vulgare), which tolerates iron (Fe) deficiency, secretes a large amount of phytosiderophores from its roots. However, how barley is able to allocate resources for phytosiderophore synthesis when the carbon assimilation rate is reduced by Fe deficiency is unknown. We previously suggested that the acceleration of senescence in older leaves triggered by Fe deficiency may allow the recycling of assimilates to contribute to phytosiderophore synthesis. In this work, we show the relationship between an increase in the C/N ratio in older leaves and Fe‐deficiency tolerance among three barley cultivars. The increase in the C/N ratio suggests an enhanced capacity for the retranslocation of carbohydrates or amino acids from older leaves to the sink organs. An increase in the sucrose concentration in Fe‐deficient barley also suggests active redistribution of assimilates. This metabolic modulation may be supported by accelerated senescence of older leaves, as Fe deficiency increased the expression of senescence‐associated genes. The older leaves of Fe‐deficient barley maintained CO2 assimilation under Fe deficiency. Barley that had been Fe‐deficient for 3 days preferentially allocated newly assimilated 13C to the roots and nutrient solution. Interestingly, the oldest leaf of Fe‐deficient barley released more 13C into the nutrient solution than the second oldest leaf. Thus, the balance between anabolism and catabolism in older leaves, supported by highly regulated senescence, plays a key role in metabolic adaptation in Fe‐deficient barley.
Does temporal preparation speed up visual processing? Evidence from the N2pc
Authors: Seibold Verena C. , Rolke Bettina
Published: February 2014

A growing number of studies show that temporal preparation, which denotes processes of anticipation and preparation for an upcoming stimulus, facilitates perceptual processing. Recently, it has been hypothesized that this perceptual benefit arises due to an acceleration of early perceptual processing. Whereas this idea receives some direct support from a recent study showing that temporal preparation reduces the latency of early auditory ERPs, supportive evidence regarding the visual modality lacks so far. To further investigate this acceleration account, we measured the latency of early visual ERPs in a visual search task. We observed that temporal preparation, manipulated via constant foreperiods, reduced the latency of early visual ERPs, specifically the N2pc as an index of attentional target processing. This finding supports a modality‐independent acceleration of perceptual processing by temporal preparation.
Microorganisms in recirculating aquaculture systems and their management
Authors: Rurangwa Eugene , Verdegem Marc C.J.
Published: February 2014

Recirculation aquaculture systems (RASs) are increasingly considered as production systems of the future with a minimum ecological impact for the production of aquatic food. To maintain a good water quality and to produce quality and healthy fishery products, the systems depend on a diverse microbial community involved in different processes of water purification but also in unwanted effects. The article reviews the present knowledge on microorganisms in RAS, their relative distribution within the system compartments and their role in system performance. The system possesses different microniches in which microorganisms retrieve their preferential conditions for oxygen and nutrients. Ammonia and nitrite are oxidized under aerobic conditions into less toxic compounds. Anaerobic ammonium oxidizers in the biofilm oxidize anaerobically both ammonia and nitrites into less harmful dinitrogen gas. Heterotrophic bacteria mineralize organic matter derived from uneaten feeds, dead bodies and excreta of fish. Under conditions of high organic load and high C/N content, nitrifiers are overgrown by heterotrophs with negative effects to the nitrification process. For not yet understood reasons, the presence of off‐flavour‐producing microorganisms occurs also in RAS. Microbial management and management of inputs to the systems to prevent the proliferation of pathogens are discussed and possible management techniques of off‐flavours are also presented. Research orientations are given to explore further the potential of heterotrophic bacteria in microbial management and intensive aquaculture production in systems other than RAS.
Neuromechanical coupling in the regulation of muscle tone and joint stiffness
Authors: Needle A. R. , Baumeister J. , Kaminski T. W. , Higginson J. S. , Farquhar W. B. , Swanik C. B.
Published: February 2014

The ability of the nervous system to accommodate changes to joint mechanics is crucial in the maintenance of joint stability and the prevention of injury. This neuromechanical coupling is achieved through several mechanisms such as the central and peripheral regulation of muscle tone and subsequent alterations to joint stiffness. Following joint injury, such as a ligamentous sprains, some patients develop functional instability or require surgery to stabilize the joint, while others are able to cope and display limited impairments. Several researchers have attempted to explain these divergent outcomes, although research using proprioceptive tasks and quantifying reaction times has led to equivocal results. Recent innovations have allowed for the simultaneous measurement of mechanical and nervous system function among these subsets. The intent of this review was to explore the relationships between joint stiffness and nervous system function, and how it changes following injury. By better understanding these mechanisms, researchers and clinicians may better develop and implement rehabilitation protocols to target individual deficits among injured populations.
Cross‐linked polyacrylates in post‐mining substrates: persistence and effects on plant growth
Authors: Rodionov A. , Nii‐Annang S. , Fischer T. , Gattinger A. , Bens O. , Raab T. , Hüttl R. F.
Published: February 2014

Application of hydrophilic polymers composed of cross‐linked polyacrylate can improve soil water‐holding capacity and accelerate the restoration of post‐mining substrates. In this work, we studied the persistence of a polyacrylate polymer incorporated into a soil and its impact on plant nutrients at a reclamation site of former lignite mining in Lusatia (Germany). In contrast to autumn application, the incorporation of the polymer enhanced the sequestration of plant‐derived carbon in the soil, which was reflected by a significant increase in the concentration of a lignin marker. Attenuated total reflexion–Fourier transform infrared spectra (ATR‐FTIR) and total elemental contents in the applied polymer suggested an intensive cation exchange between the polymer framework and the soil‐forming substrate. In addition, there was an enrichment of carbonaceous material, which seems to reduce the swelling and thus the water‐holding capacity of the cross‐linked polyacrylate. Conversely, this process protected the polymer structure from rapid decomposition.
Reduced prevalence of Giardia duodenalis in iron‐deficient Rwandan children
Authors: Danquah Ina , Gahutu Jean‐Bosco , Ignatius Ralf , Musemakweri Andre , Mockenhaupt Frank P.
Published: February 2014

Objective

Acute symptomatic infection with Giardia duodenalis impairs iron absorption, but iron deficiency may protect against infections caused by various micro‐organisms including parasites. We therefore examined the association of G. duodenalis infection and iron deficiency in 575 Rwandan children under 5 years of age.

Methods

Giardia duodenalis infection was diagnosed by triplicate microscopy and PCR assays, and iron deficiency was defined as a ferritin concentration <12 ng/ml.

Results

Largely asymptomatic G. duodenalis infection was seen in 65.3% of the children and iron deficiency in 17.4%. G. duodenalis infection was less common in iron‐deficient children (51%) than in non‐deficient children (68%, P = 0.002). In multivariate analysis, the odds of G. duodenalis infection were almost halved in iron‐deficient children (adjusted odds ratio, 0.54; 95% confidence interval, 0.33–0.86).

Conclusion

In this highly endemic setting, there was no evidence that Giardia infection impairs iron status. Rather, iron deficiency appeared to protect against infection with this parasite.
Polarised Clathrin‐Mediated Endocytosis of EGFR During Chemotactic Invasion
Authors: Mutch Laura Jane , Howden Jake Davey , Jenner Emma Poppy Louise , Poulter Natalie Sarah , Rappoport Joshua Zachary
Published: February 2014

Directed cell migration is critical for numerous physiological processes including development and wound healing. However chemotaxis is also exploited during cancer progression. Recent reports have suggested links between vesicle trafficking pathways and directed cell migration. Very little is known about the potential roles of endocytosis pathways during metastasis. Therefore we performed a series of studies employing a previously characterised model for chemotactic invasion of cancer cells to assess specific hypotheses potentially linking endocytosis to directed cell migration. Our results demonstrate that clathrin‐mediated endocytosis is indispensable for epidermal growth factor (EGF) directed chemotactic invasion of MDA‐MB‐231 cells. Conversely, caveolar endocytosis is not required in this mode of migration. We further found that chemoattractant receptor (EGFR) trafficking occurs by clathrin‐mediated endocytosis and is polarised towards the front of migrating cells. However, we found no role for clathrin‐mediated endocytosis in focal adhesion disassembly in this migration model. Thus, this study has characterised the role of endocytosis during chemotactic invasion and has identified functions mechanistically linking clathrin‐mediated endocytosis to directed cell motility.
Mean remaining life span: a new clinically relevant parameter to assess the quality of transfused red blood cells
Authors: Kuruvilla Denison J. , Nalbant Demet , Widness John A. , Veng‐Pedersen Peter
Published: February 2014

Background

The quality of transfused red blood cells (RBCs) to treat anemia depends on its potential for oxygen delivery, governed by two properties: 1) initial posttransfusion recovery and 2) life span of initially surviving RBCs. The latter property is poorly evaluated by the traditional mean potential life span (MPL) or mean cell age (MA), because these parameters do not evaluate how long transfused RBCs remain in circulation. Furthermore, evaluation of MPL is based on two problematic assumptions regarding transfused RBCs: 1) they were produced at a constant steady‐state rate and 2) they have similar storage life spans.

Study Design and Methods

This work introduces a new parameter, the mean remaining life span (MRL) to quantify transfused RBC survival (TRCS) and presents a simple algorithm for its evaluation. The MRL was calculated for four adult subjects with sickle cell disease and four adult diabetic and nondiabetic subjects using RBC survival data sets with existing TRCS parameters.

Results

The RBC survival curves in the sickle cell subjects were nonlinear with rapid decline in survival within the first 5 days. The MRL was approximately 4.6 days. Thus, the MRL was indicative of the survival of all transfused RBCs. For the diabetic and nondiabetic subjects, the RBC disappearance curves did not deviate substantially from a linear decline. Thus, the estimates for MRL ranging from 39 to 51 days are similar to the MA previously computed.

Conclusion

MRL overcomes limitations of previously proposed TRCS parameters, is simpler to calculate, and is physiologically and clinically more appropriate.