bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of tetrahydrobiopterin and catecholamines in the developmental regulation of tyrosine hydroxylase level in the brain
Authors: Homma Daigo , Katoh Setsuko , Tokuoka Hirofumi , Ichinose Hiroshi
Published: May 2013

Tyrosine hydroxylase (TH) is a rate‐limiting enzyme for dopamine synthesis and requires tetrahydrobiopterin (BH4) as an essential cofactor. BH4 deficiency leads to the loss of TH protein in the brain, although the underlying mechanism is poorly understood. To give insight into the role of BH4 in the developmental regulation of TH protein level, in this study, we investigated the effects of acute and subchronic administrations of BH4 or dopa on the TH protein content in BH4‐deficient mice lacking sepiapterin reductase. We found that BH4 administration persistently elevated the BH4 and dopamine levels in the brain and fully restored the loss of TH protein caused by the BH4 deficiency in infants. On the other hand, dopa administration less persistently increased the dopamine content and only partially but significantly restored the TH protein level in infant BH4‐deficient mice. We also found that the effects of BH4 or dopa administration on the TH protein content were attenuated in young adulthood. Our data demonstrate that BH4 and catecholamines are required for the post‐natal augmentation of TH protein in the brain, and suggest that BH4 availability in early post‐natal period is critical for the developmental regulation of TH protein level.
Noma (cancrum oris) in the South African context
Authors: Feller L. , Altini M. , Chandran R. , Khammissa R. A. G. , Masipa J. N. , Mohamed A. , Lemmer J.
Published: May 2013

Noma (cancrum oris) is a destructive necrotising disease affecting orofacial tissues predominantly of malnourished young children. It is characterised by a rapid acute onset which usually starts in the mouth, spreads intra‐orally destroying soft tissue and bone and progresses to perforate the facial skin, causing disfigurement. Polybacterial anaerobic infection is critical too, but is not alone sufficient for the initiation of noma. Cofactors, first and foremost malnutrition, but also systemic viral and bacterial infections are crucial to the development of noma. A patient with necrotising stomatitis or noma must be admitted to hospital for antibiotic treatment, fluid and electrolytes as well as nutritional supplementation and general supportive treatment. The epidemiology of noma in the South African population is unknown, and the clinicopathological features are poorly characterised. Although worldwide there is no evidence that HIV infection is a strong risk factor for noma, HIV infection may play a substantial role in the pathogenesis of noma in South Africa.
Establishment of odontoblastic cells, which indicate odontoblast features both in vivo and in vitro
Authors: Tsujigiwa Hidetsugu , Katase Naoki , Lefeuvre Mathieu , Yamachika Eiki , Tamamura Ryo , Ito Satoshi , Takebe Yuichiro , Matsuda Hiroyuki , Nagatsuka Hitoshi
Published: May 2013

Tooth tissue engineering offers very attractive perspectives for elaboration of regenerative treatments, which enables to cure tooth loss and restore quality of life of the patients. To elaborate such treatment, isolation and culture of dental pulp cell must be achieved as a key element. In this article, we report the establishment of a stable cell line from GFP transgenic rat dental pulp, named TGC (Tooth Matrix‐forming, GFP Rat‐derived Cell). TGCs have exhibited odontoblastic feature both in vitro and in vivo. In vitro, TGC exposed to osteogenic medium demonstrated collagen fiber synthesis with matrix vesicle and mineralization and formed a sheet‐like substrate on the cell culture dish. Increased ALP activity and elevated transcription level of various genes involved in calcification and dentin formation were also observed. In vivo, transplanted TGC in SCID mice with β‐TCP particles formed dentin‐like and pulp‐like structure with lining odontoblast. Notably, even after up to 80 passages, TGCs retain their morphological features and differentiation ability. To our knowledge, this is the first report of a dental pulp–derived cell with such stable odontoblastic characteristics. TGC could be a very useful model for further study on dental pulp cell.
Frequency of hyperbolic and interstellar meteoroids
Authors: Hajduková Maria , Kornoš Leonard , Tóth Juraj
Published: May 2013

Hyperbolic meteor orbits from the catalog of 64,650 meteors observed by the multistation video meteor network located in Japan (SonotaCo 2009) have been investigated with the aim of determining the relation between the frequency of hyperbolic and interstellar meteors. The proportion of hyperbolic meteors in the data decreased significantly (from 11.58% to 3.28%) after a selection of quality orbits, which shows its dependence on the quality of observations. Initially, the hyperbolic orbits were searched for meteors unbound due to planetary perturbation. It was determined that 22 meteors from the 7489 hyperbolic orbits in the catalog (and 2 from the selection of the orbits with the highest quality) had had a close encounter with a planet, none of which, however, produced essential changes in their orbits. Similarly, the fraction of hyperbolic orbits in the data, which could be hyperbolic by reason of a meteor's interstellar origin, was determined to be at most 3.9 × 10−2. From the statistical point of view, the vast majority of hyperbolic meteors in the database have definitely been caused by inaccuracy in the velocity determination. This fact does not necessarily assume great measurement errors, since, especially near the parabolic limit, a small error in the value of the heliocentric velocity of a meteor can create an artificial hyperbolic orbit that does not really exist. The results show that the remaining 96% of meteoroids with apparent hyperbolic orbits belong to the solar system meteoroid population. This is also supported by their high abundance (about 50%) among the meteor showers.
Nanomechanical analysis of pigmented human melanoma cells
Authors: Sarna Michal , Zadlo Andrzej , Pilat Anna , Olchawa Magdalena , Gkogkolou Paraskevi , Burda Kvetoslava , Böhm Markus , Sarna Tadeusz
Published: May 2013

Based on hitherto measurements of elasticity of various cells in vitro and ex vivo, cancer cells are generally believed to be much softer than their normal counterparts. In spite of significant research efforts on the elasticity of cancer cells, only few studies were undertaken with melanoma cells. However, there are no reports concerning pigmented melanoma cells. Here, we report for the first time on the elasticity of pigmented human melanoma cells. The obtained data show that melanin significantly increases the stiffness of pigmented melanoma cells and that the effect depends on the amount of melanin inside the cells. The dramatic impact of melanin on the nanomechanical properties of cells puts into question widely accepted paradigm about all cancer cells being softer than their normal counterparts. Our findings reveal significant limitations of the nanodiagnosis approach for melanoma and contribute to better understanding of cell elasticity.
Photoreduction of Azaoxoisoaporphines by Amines: Laser Flash and Steady‐State Photolysis and Pulse Radiolysis Studies
Authors: de la Fuente Julio R. , Aliaga Christian , Cañete Alvaro , Kciuk Gabriel , Szreder Tomasz , Bobrowski Krzysztof
Published: May 2013

Photoreduction of 7H‐benzo[e]perimidin‐7‐one (3‐AOIA, A1) and its 2‐methyl derivative (2‐Me‐3‐AOIA, A2) by non‐H‐donating amines (1,4‐diazabicyclo[2.2.2]octane [DABCO]; 2,2,6,6‐tetramethylpiperidine [TMP]), and a hydrogen‐donating amine (triethylamine [TEA]), has been studied in deaerated neat acetonitrile solutions using laser flash photolysis (LFP) and steady‐state photolysis. The triplet excited states of A1 and A2 were characterized by a strong absorption band with λmax = 440 nm and lifetimes of 20 and 27 μs respectively. In the presence of tertiary amines, both triplet excited states were quenched with rate constants close to the diffusional limit (kq ranged between 109 and 1010 M−1 s−1). The transient absorption spectra observed after quenching with DABCO and TMP were characterized by maxima located at 460 nm and broad shoulders in the range of 500–600 nm. These transient species are attributed to solvent‐separated radical ion pairs and/or to isolated radical anions. In the presence of TEA, these transients undergo proton transfer, leading to the neutral hydrogenated radicals, protonated over the N1‐ and O‐atoms. Transient absorption spectra of these transients were characterized by maxima located at 400 and 520 nm and 430 nm respectively. Additional support for these spectral assignments was provided by pulse radiolysis (PR) experiments in acetonitrile and 2‐propanol solutions.
Study of the Mode and Efficiency of DNA Binding in the Damage Induced by Photoactivated Water Soluble Porphyrins
Authors: Karunakaran Suneesh C. , Ramaiah Danaboyina , Schulz Ina , Epe Bernd
Published: May 2013

We have investigated the DNA binding interactions and in vitro photoactivated DNA damage induced by a neutral water soluble porphyrin derivative 5,10,15,20‐tetrakis(2,4,6‐trihydroxyphenyl)porphyrin (TTHPP) and its zinc derivative 5,10,15,20‐tetrakis(2,4,6‐trihydroxyphenyl)porphyrinato zinc(II) (Zn‐TTHPP) upon visible light irradiation through various spectroscopic techniques and employing repair endonucleases. These porphyrin derivatives exhibited high affinity toward DNA through groove binding interactions as evidenced through the UV–vis absorption, emission, circular dichroism spectral and viscosity changes. Interestingly, the free base porphyrin derivative, TTHPP generated efficient singlet oxygen mediated DNA damage sensitive to formamidopyrimidine‐DNA glycosylase (Fpg protein), when compared with its metal derivative and to the well‐known photosensitizer, hematoporphyrin. These results provide direct evidence for the role of DNA binding mode as well as extent of interactions with DNA in the efficiency of photoactivated DNA damage induced by the neutral porphyrins, which are believed to be the ideal candidates for photodynamic therapeutic applications.
In Situ Synthesis and Characterization of Nano ZnO on Wool: Influence of Nano Photo Reactor on Wool Properties
Authors: Montazer Majid , Amiri Morteza Maali , Mohammad Ali Malek Reza
Published: May 2013

This study has been carried out to synthesize nano ZnO on wool fabric and also to investigate influences of nano photo reactors on wool fabric characteristics. Zinc acetate has been used as a precursor and the synthesis process has been done in water and water/ethanol media. The treated wool fabrics were heated at 80°C for 10 h to dehydrate Zn(OH)2 obtaining ZnO. The fabric samples were then subjected to daylight for 7 days to examine the influence of nano ZnO photo reactor on the fabric properties. SEM images revealed the embedding of ZnO nanoparticles on the fabrics and X‐ray diffraction verified the nanoparticles composition. The Yellowness Index (YI) of the fabrics was measured with Color Eye XTH that has been reduced with increasing pH, Zn(CH3COO)2 concentration, ethanol and heating. The lower water contact angle and time of water absorption confirmed higher hydrophilic properties of the treated fabrics. Interestingly, a higher tensile strength obtained on the wool fabrics proved the interaction of ZnO with protein chains of wool, which was verified through lower alkali solubility of treated fabric with nano ZnO and confirmed more benefits of the in situ synthesis process.
Consecutive transcranial magnetic stimulation twitches reduce flow limitation during sleep in apnoeic patients
Authors: Melo‐Silva César Augusto , Gakwaya Simon , Rousseau Eric , Sériès Frédéric
Published: May 2013

New Findings

What is the central question of this study?

A transcranial magnetic stimulation (TMS)‐induced twitch applied on isolated single breaths over the motor cortex somatotopic representation of the tongue briefly recruits submental muscles and improves airflow dynamics of flow‐limited respiratory cycles without arousing sleep apnoea patients. However, the mechanical impact of the TMS‐induced twitch applied during consecutive breathing cycles on airflow dynamics remains unknown.

What is the main finding and what is its importance?

Our results show that application of TMS with the stimulator output set at the sleep submental motor threshold intensity on consecutive respiratory cycles increases inspiratory flow and reduces the turbulent airflow component. These results indicate an improvement of airflow pattern after two single consecutive TMS‐induced twitches without arousing sleep apnoea patients.

Transcranial magnetic stimulation (TMS)‐induced twitches applied on isolated breaths briefly recruit upper airway dilator muscles and improve airflow and inspiratory volume without arousing apnoeic patients from sleep, but the effects of applying such twitches consecutively on airflow dynamics is unknown. The objective of this study was to quantify the effects of five consecutive TMS‐induced twitches applied on sleep‐induced obstructive hypopnoeic breaths in 10 obstructive sleep apnoea patients. Submental muscle motor threshold (SUBMT) and motor‐evoked potential were measured during wakefulness and sleep. The TMS‐induced twitches were applied during stable non‐rapid eye movement (NREM) sleep, at the beginning of inspiration of consecutive flow‐limited respiratory cycles, with the stimulator output set at sleep SUBMT. Maximal inspiratory flow, inspiratory volume, inspiratory time, shifts of electroencephalogram frequency and pulse rate variability were assessed. During sleep, SUBMT increased (wakefulness, 25.3 ± 4.9%; NREM sleep, 27.0 ± 6.2%; P= 0.02). During each series of stimulations there was a rise in maximal inspiratory flow (from 306.7 ± 123.2 to 359.8 ± 154.1 ml s−1; P= 0.0002) and in inspiratory volume (from 346.1 ± 128.1 to 414.9 ± 171.2 ml; P= 0.02) without differences in thoraco‐abdominal efforts and inspiratory time. These responses were observed in the absence of arousals and ceased immediately after TMS interruption. Transcranial magnetic stimulation‐induced cortical and/or autonomic arousal was observed in 30.2% of all series of stimulation. Consecutive twitch TMS of submental muscles may lead to arousals in a minority of patients but can be applied on consecutive respiratory cycles during sleep and can significantly improve maximal inspiratory flow and inspiratory volume of flow‐limited cycles.
The Interleukin-1 Receptor/Toll-like Receptor Superfamily: Signal Transduction During Inflammation and Host Defense
Authors: O'Neill Luke A. J.
Published: May 2013

The signal transduction pathways activated by the proinflammatory cytokine interleukin-1 (IL-1) have been the focus of much attention because of the important role that IL-1 plays in inflammatory diseases. A number of proteins have been described that participate in the post-receptor activation of the transcription factor NF-κB and stress-activated protein kinases such as p38 mitogen-activated protein kinase (MAPK). It has also emerged that the type I IL-1 receptor (termed IL-1RI) is a member of an expanding receptor superfamily. These related receptors all have sequence similarity in their cytosolic regions. The family includes the
Drosophila melanogaster
protein Toll, the IL-18 receptor (IL-18R), and the Toll-like receptors TLR-2 and TLR-4, which bind molecules from Gram-positive and Gram-negative bacteria, respectively. Because of the similarity of IL-1RI to Toll, the conserved sequence in the cytosolic region of these proteins has been termed the Toll-IL-1 receptor (TIR) domain. The same proteins activated during signaling by IL-1RI also participate in signaling by IL-18R and TLR-4. The receptor superfamily is evolutionarily conserved; members occur in plants and insects and also function in host defense. The signaling proteins activated are also conserved across species. This receptor superfamily therefore represents an ancient signaling system that is a critical determinant of the innate immune and inflammatory responses.
What Do Scaffold Proteins Really Do?
Authors: Ferrell James E.
Published: May 2013

Scaffold proteins play an important role in coordinating signal transduction cascades. However, their exact mechanism of action and the ultimate effect they have on the signal output remain unclear. Ferrell discusses how computer simulations have provided insight into the multiple possible functions that scaffold proteins may have. What remains is to test the predictions in real cells to determine what difference the presence of a scaffold really makes in the output of a signaling pathway.
Activity and Viability of Methanogens in Anaerobic Digestion of Unsaturated and Saturated Long-Chain Fatty Acids
Authors: Sousa Diana Z. , Salvador Andreia F. , Ramos Juliana , Guedes Ana P. , Barbosa Sï¿½nia , Stams Alfons J. M. , Alves M. Madalena , Pereira M. Alcina
Published: May 2013

Lipids can be anaerobically digested to methane, but methanogens are often considered to be highly sensitive to the long-chain fatty acids (LCFA) deriving from lipids hydrolysis. In this study, the effect of unsaturated (oleate [C
18:1
]) and saturated (stearate [C
18:0
] and palmitate [C
16:0
]) LCFA toward methanogenic archaea was studied in batch enrichments and in pure cultures. Overall, oleate had a more stringent effect on methanogens than saturated LCFA, and the degree of tolerance to LCFA was different among distinct species of methanogens.
Methanobacterium formicicum
was able to grow in both oleate- and palmitate-degrading enrichments (OM and PM cultures, respectively), whereas
Methanospirillum hungatei
only survived in a PM culture. The two acetoclastic methanogens tested,
Methanosarcina mazei
and
Methanosaeta concilii
, could be detected in both enrichment cultures, with better survival in PM cultures than in OM cultures. Viability tests using live/dead staining further confirmed that exponential growth-phase cultures of
M. hungatei
are more sensitive to oleate than are
M. formicicum
cultures; exposure to 0.5 mM oleate damaged 99% ï¿½ 1% of the cell membranes of
M. hungatei
and 53% ï¿½ 10% of the cell membranes of
M. formicicum
. In terms of methanogenic activity,
M. hungatei
was inhibited for 50% by 0.3, 0.4, and 1 mM oleate, stearate, and palmitate, respectively.
M. formicicum
was more resilient, since 1 mM oleate and >4 mM stearate or palmitate was needed to cause 50% inhibition on methanogenic activity.
New Group in the Leptospirillum Clade: Cultivation-Independent Community Genomics, Proteomics, and Transcriptomics of the New Species “Leptospirillum Group IV UBA BS”
Authors: Goltsman Daniela S. Aliaga , Dasari Mauna , Thomas Brian C. , Shah Manesh B. , VerBerkmoes Nathan C. , Hettich Robert L. , Banfield Jillian F.
Published: May 2013

Leptospirillum
spp. are widespread members of acidophilic microbial communities that catalyze ferrous iron oxidation, thereby increasing sulfide mineral dissolution rates. These bacteria play important roles in environmental acidification and are harnessed for bioleaching-based metal recovery. Known members of the
Leptospirillum
clade of the
Nitrospira
phylum are
Leptospirillum ferrooxidans
(group I),
Leptospirillum ferriphilum
and “
Leptospirillum rubarum
” (group II), and
Leptospirillum ferrodiazotrophum
(group III). In the Richmond Mine acid mine drainage (AMD) system, biofilm formation is initiated by
L. rubarum
;
L. ferrodiazotrophum
appears in later developmental stages. Here we used community metagenomic data from unusual, thick floating biofilms to identify distinguishing metabolic traits in a rare and uncultivated community member, the new species “
Leptospirillum
group IV UBA BS.” These biofilms typically also contain a variety of
Archaea
,
Actinobacteria
, and a few other
Leptospirillum
spp. The
Leptospirillum
group IV UBA BS species shares 98% 16S rRNA sequence identity and 70% average amino acid identity between orthologs with its closest relative,
L. ferrodiazotrophum
. The presence of nitrogen fixation and reverse tricarboxylic acid (TCA) cycle proteins suggest an autotrophic metabolism similar to that of
L. ferrodiazotrophum
, while hydrogenase proteins suggest anaerobic metabolism. Community transcriptomic and proteomic analyses demonstrate expression of a multicopper oxidase unique to this species, as well as hydrogenases and core metabolic genes. Results suggest that the
Leptospirillum
group IV UBA BS species might play important roles in carbon fixation, nitrogen fixation, hydrogen metabolism, and iron oxidation in some acidic environments.
Insights into Exo- and Endoglucanase Activities of Family 6 Glycoside Hydrolases from Podospora anserina
Authors: Poidevin Laetitia , Feliu Julia , Doan Annick , Berrin Jean-Guy , Bey Mathieu , Coutinho Pedro M. , Henrissat Bernard , Record Eric , Heiss-Blanquet Senta
Published: May 2013

The ascomycete
Podospora anserina
is a coprophilous fungus that grows at late stages on droppings of herbivores. Its genome encodes a large diversity of carbohydrate-active enzymes. Among them, four genes encode glycoside hydrolases from family 6 (GH6), the members of which comprise putative endoglucanases and exoglucanases, some of them exerting important functions for biomass degradation in fungi. Therefore, this family was selected for functional analysis. Three of the enzymes,
P. anserina
Cel6A (
Pa
Cel6A),
Pa
Cel6B, and
Pa
Cel6C, were functionally expressed in the yeast
Pichia pastoris
. All three GH6 enzymes hydrolyzed crystalline and amorphous cellulose but were inactive on hydroxyethyl cellulose, mannan, galactomannan, xyloglucan, arabinoxylan, arabinan, xylan, and pectin.
Pa
Cel6A had a catalytic efficiency on cellotetraose comparable to that of
Trichoderma reesei
Cel6A (
Tr
Cel6A), but
Pa
Cel6B and
Pa
Cel6C were clearly less efficient.
Pa
Cel6A was the enzyme with the highest stability at 45ï¿½C, while
Pa
Cel6C was the least stable enzyme, losing more than 50% of its activity after incubation at temperatures above 30ï¿½C for 24 h. In contrast to
Tr
Cel6A, all three studied
P. anserina
GH6 cellulases were stable over a wide range of pHs and conserved high activity at pH values of up to 9. Each enzyme displayed a distinct substrate and product profile, highlighting different modes of action, with
Pa
Cel6A being the enzyme most similar to
Tr
Cel6A.
Pa
Cel6B was the only enzyme with higher specific activity on carboxymethylcellulose (CMC) than on Avicel and showed lower processivity than the others. Structural modeling predicts an open catalytic cleft, suggesting that
Pa
Cel6B is an endoglucanase.
Insights into the Structure and Metabolic Function of Microbes That Shape Pelagic Iron-Rich Aggregates (“Iron Snow”)
Authors: Lu Shipeng , Chourey Karuna , Reiche Marco , Nietzsche Sandor , Shah Manesh B. , Neu Thomas R. , Hettich Robert L. , Kï¿½sel Kirsten
Published: May 2013

Microbial ferrous iron [Fe(II)] oxidation leads to the formation of iron-rich macroscopic aggregates (“iron snow”) at the redoxcline in a stratified lignite mine lake in east-central Germany. We aimed to identify the abundant Fe-oxidizing and Fe-reducing microorganisms likely to be involved in the formation and transformation of iron snow present in the redoxcline in two basins of the lake that differ in their pH values. Nucleic acid- and lipid-stained microbial cells of various morphologies detected by confocal laser scanning microscopy were homogeneously distributed in all iron snow samples. The dominant iron mineral appeared to be schwertmannite, with shorter needles in the northern than in the central basin samples. Total bacterial 16S rRNA gene copies ranged from 5.0 ï¿½ 10
8
copies g (dry weight)
−1
in the acidic central lake basin (pH 3.3) to 4.0 ï¿½ 10
10
copies g (dry weight)
−1
in the less acidic (pH 5.9) northern basin. Total RNA-based quantitative PCR assigned up to 61% of metabolically active microbial communities to Fe-oxidizing- and Fe-reducing-related bacteria, indicating that iron metabolism was an important metabolic strategy. Molecular identification of abundant groups suggested that iron snow surfaces were formed by chemoautotrophic iron oxidizers, such as
Acidimicrobium
,
Ferrovum
,
Acidithiobacillus
,
Thiobacillus
, and
Chlorobium
, in the redoxcline and were rapidly colonized by heterotrophic iron reducers, such as
Acidiphilium
,
Albidiferax
-like, and
Geobacter
-like groups. Metaproteomics yielded 283 different proteins from northern basin iron snow samples, and protein identification provided a glimpse into some of their
in situ
metabolic processes, such as primary production (CO
2
fixation), respiration, motility, and survival strategies.
Adaptation of the Hydrocarbonoclastic Bacterium Alcanivorax borkumensis SK2 to Alkanes and Toxic Organic Compounds: a Physiological and Transcriptomic Approach
Authors: Naether Daniela J. , Slawtschew Slavtscho , Stasik Sebastian , Engel Maria , Olzog Martin , Wick Lukas Y. , Timmis Kenneth N. , Heipieper Hermann J.
Published: May 2013

The marine hydrocarbonoclastic bacteriumAlcanivorax borkumensisis able to degrade mixtures ofn-alkanes as they occur in marine oil spills. However, investigations of growth behavior and physiology of these bacteria when cultivated withn-alkanes of different chain lengths (C6to C30) as the substrates are still lacking. Growth rates increased with increasing alkane chain length up to a maximum between C12and C19, with no evident difference between even- and odd-numbered chain lengths, before decreasing with chain lengths greater than C19. Surface hydrophobicity of alkane-grown cells, assessed by determination of the water contact angles, showed a similar pattern, with maximum values associated with growth rates on alkanes with chain lengths between C11and C19and significantly lower values for cells grown on pyruvate.A. borkumensiswas found to incorporate and modify the fatty acid intermediates generated by the correspondingn-alkane degradation pathway. Cells grown on distinctn-alkanes proved thatA. borkumensisis able to not only incorporate but also modify fatty acid intermediates derived from the alkane degradation pathway. Comparing cells grown on pyruvate with those cultivated on hexadecane in terms of their tolerance toward two groups of toxic organic compounds, chlorophenols and alkanols, representing intensely studied organic compounds, revealed similar tolerances toward chlorophenols, whereas the toxicities of differentn-alkanols were significantly reduced when hexadecane was used as a carbon source. As one adaptive mechanism ofA. borkumensisto these toxic organic solvents, the activity ofcis-transisomerization of unsaturated fatty acids was proven. These findings could be verified by a detailed transcriptomic comparison between cultures grown on hexadecane and pyruvate and including solvent stress caused by the addition of 1-octanol as the most toxic intermediate ofn-alkane degradation.
Novel Rickettsiella Bacterium in the Leafhopper Orosius albicinctus (Hemiptera: Cicadellidae)
Authors: Iasur-Kruh Lilach , Weintraub Phyllis G. , Mozes-Daube Netta , Robinson Wyatt E. , Perlman Steve J. , Zchori-Fein Einat
Published: May 2013

Bacteria in the genus
Rickettsiella
(
Coxiellaceae
), which are mainly known as arthropod pathogens, are emerging as excellent models to study transitions between mutualism and pathogenicity. The current report characterizes a novel
Rickettsiella
found in the leafhopper
Orosius albicinctus
(Hemiptera: Cicadellidae), a major vector of phytoplasma diseases in Europe and Asia. Denaturing gradient gel electrophoresis (DGGE) and pyrosequencing were used to survey the main symbionts of
O. albicinctus
, revealing the obligate symbionts
Sulcia
and
Nasuia
, and the facultative symbionts
Arsenophonus
and
Wolbachia
, in addition to
Rickettsiella
. The leafhopper
Rickettsiella
is allied with bacteria found in ticks. Screening
O. albicinctus
from the field showed that
Rickettsiella
is highly prevalent, with over 60% of individuals infected. A stable
Rickettsiella
infection was maintained in a leafhopper laboratory colony for at least 10 generations, and fluorescence microscopy localized bacteria to accessory glands of the female reproductive tract, suggesting that the bacterium is vertically transmitted. Future studies will be needed to examine how
Rickettsiella
affects host fitess and its ability to vector phytopathogens.
Enzymatic Synthesis and Characterization of Fructooligosaccharides and Novel Maltosylfructosides by Inulosucrase from Lactobacillus gasseri DSM 20604
Authors: Díez-Municio Marina , de las Rivas Blanca , Jimeno Maria Luisa , Muñoz Rosario , Moreno F. Javier , Herrero Miguel
Published: May 2013

The ability of an inulosucrase (IS) from
Lactobacillus gasseri
DSM 20604 to synthesize fructooligosaccharides (FOS) and maltosylfructosides (MFOS) in the presence of sucrose and sucrose-maltose mixtures was investigated after optimization of synthesis conditions, including enzyme concentration, temperature, pH, and reaction time. The maximum formation of FOS, which consist of β-2,1-linked fructose to sucrose, was 45% (in weight with respect to the initial amount of sucrose) and was obtained after 24 h of reaction at 55°C in the presence of sucrose (300 g liter
−1
) and 1.6 U ml
−1
of IS–25 mM sodium acetate buffer–1 mM CaCl
2
(pH 5.2). The production of MFOS was also studied as a function of the initial ratios of sucrose to maltose (10:50, 20:40, 30:30, and 40:20, expressed in g 100 ml
−1
). The highest yield in total MFOS was attained after 24 to 32 h of reaction time and ranged from 13% (10:50 sucrose/maltose) to 52% (30:30 sucrose/maltose) in weight with respect to the initial amount of maltose. Nuclear magnetic resonance (NMR) structural characterization indicated that IS from
L. gasseri
specifically transferred fructose moieties of sucrose to either C-1 of the reducing end or C-6 of the nonreducing end of maltose. Thus, the trisaccharide erlose [α-
d
-glucopyranosyl-(1→4)-α-
d
-glucopyranosyl-(1→2)-β-
d
-fructofuranoside] was the main synthesized MFOS followed by neo-erlose [β-
d
-fructofuranosyl-(2→6)-α-
d
-glucopyranosyl-(1→4)-α-
d
-glucopyranose]. The formation of MFOS with a higher degree of polymerization was also demonstrated by the transfer of additional fructose residues to C-1 of either the β-2,1-linked fructose or the β-2,6-linked fructose to maltose, revealing the capacity of MFOS to serve as acceptors.
Comparative Genomics of Bifidobacterium animalis subsp. lactis Reveals a Strict Monophyletic Bifidobacterial Taxon
Authors: Milani Christian , Duranti Sabrina , Lugli Gabriele Andrea , Bottacini Francesca , Strati Francesco , Arioli Stefania , Foroni Elena , Turroni Francesca , van Sinderen Douwe , Ventura Marco
Published: May 2013

Strains of
Bifidobacterium animalis
subsp.
lactis
are extensively exploited by the food industry as health-promoting bacteria, although the genetic variability of members belonging to this taxon has so far not received much scientific attention. In this article, we describe the complete genetic makeup of the
B. animalis
subsp.
lactis
Bl12 genome and discuss the genetic relatedness of this strain with other sequenced strains belonging to this taxon. Moreover, a detailed comparative genomic analysis of
B. animalis
subsp.
lactis
genomes was performed, which revealed a closely related and isogenic nature of all currently available
B. animalis
subsp.
lactis
strains, thus strongly suggesting a closed pan-genome structure of this bacterial group.
Engineering the Soil Bacterium Pseudomonas putida for Arsenic Methylation
Authors: Chen Jian , Qin Jie , Zhu Yong-Guan , de Lorenzo Vï¿½ctor , Rosen Barry P.
Published: May 2013

Accumulation of arsenic has potential health risks through consumption of food. Here, we inserted the arsenite [As(III)]
S
-adenosylmethionine methyltransferase (ArsM) gene into the chromosome of
Pseudomonas putida
KT2440. Recombinant bacteria methylate inorganic arsenic into less toxic organoarsenicals. This has the potential for bioremediation of environmental arsenic and reducing arsenic contamination in food.
Environmental Factors Influencing the Prevalence of a Clostridium botulinum Type C/D Mosaic Strain in Nonpermanent Mediterranean Wetlands
Authors: Vidal Dolors , Anza Ibone , Taggart Mark A. , Pï¿½rez-Ramï¿½rez Elisa , Crespo Elena , Hofle Ursula , Mateo Rafael
Published: May 2013

Between 1978 and 2008, 13 avian botulism outbreaks were recorded in the wetlands of Mancha Hï¿½meda (central Spain). These outbreaks caused the deaths of around 20,000 birds from over 50 species, including globally endangered white-headed ducks (
Oxyura leucoceophala
). Here, a significant association was found between the number of dead birds recorded in each botulism outbreak and the mean temperature in July (always >26ï¿½C). The presence of
Clostridium botulinum
type C/D in wetland sediments was detected by real-time PCR (quantitative PCR [qPCR]) in 5.8% of 207 samples collected between 2005 and 2008. Low concentrations of Cl
−
and high organic matter content in sediments were significantly associated with the presence of
C. botulinum
. Seventy-five digestive tracts of birds found dead during botulism outbreaks were analyzed;
C. botulinum
was present in 38.7% of them. The prevalence of
C. botulinum
was 18.2% (
n
= 22 pools) in aquatic invertebrates (Chironomidae and Corixidae families) and 33.3% (
n
= 18 pools) in necrophagous invertebrates (Sarcophagidae and Calliphoridae families), including two pools of adult necrophagous flies collected around bird carcasses. The presence of the bacteria in the adult fly form opens up new perspectives in the epidemiology of avian botulism, since these flies may be transporting
C. botulinum
from one carcass to another.
Low-pH Rescue of Acid-Sensitive Salmonella enterica Serovar Typhi Strains by a Rhamnose-Regulated Arginine Decarboxylase System
Authors: Brenneman Karen E. , Willingham Crystal , Kong Wei , Curtiss Roy , Roland Kenneth L.
Published: May 2013

For
Salmonella
, transient exposure to gastric pH prepares invading bacteria for the stresses of host-cell interactions. To resist the effects of low pH, wild-type
Salmonella enterica
uses the acid tolerance response and the arginine decarboxylase acid resistance system. However, arginine decarboxylase is typically repressed under routine culture conditions, and for many live attenuated
Salmonella
vaccine strains, the acid tolerance response is unable to provide the necessary protection. The objective of this study was to enhance survival of
Salmonella enterica
serovar Typhi vaccine strains at pHs 3.0 and 2.5 to compensate for the defects in the acid tolerance response imposed by mutations in
rpoS
,
phoPQ
, and
fur
. We placed the arginine decarboxylase system (
adiA
and
adiC
) under the control of the P

araBAD

or P

rhaBAD

promoter to provide inducible acid resistance when cells are grown under routine culture conditions. The rhamnose-regulated promoter P

rhaBAD

was less sensitive to the presence of its cognate sugar than the arabinose-regulated promoter P

araBAD

and provided tighter control over
adiA
expression. Increased survival at low pH was only observed when
adiA
and
adiC
were coregulated by rhamnose and depended on the presence of rhamnose in the culture medium and arginine in the challenge medium. Rhamnose-regulated acid resistance significantly improved the survival of Δ
aroD
and Δ
phoPQ
mutants at pHs 3 and 2.5 but only modestly improved the survival of a
fur
mutant. The construction of the rhamnose-regulated arginine decarboxylase system allowed us to render
S
. Typhi acid resistant (to pH 2.5) on demand, with survival levels approximately equivalent to that of the native arginine decarboxylase system.
Enterococcal Rgg-Like Regulator ElrR Activates Expression of the
elrA
Operon
Authors: Dumoulin Romain , Cortes-Perez Naima , Gaubert Stephane , Duhutrel Philippe , Brinster Sophie , Torelli Riccardo , Sanguinetti Maurizio , Posteraro Brunella , Repoila Francis , Serror Pascale
Published: May 2013

The
Enterococcus faecalis
leucine-rich protein ElrA promotes virulence by stimulating bacterial persistence in macrophages and production of the interleukin-6 (IL-6) cytokine. The ElrA protein is encoded within an operon that is poorly expressed under laboratory conditions but induced
in vivo
. In this study, we identify
ef2687
(renamed
elrR
), which encodes a member of the Rgg (
r
egulator
g
ene for
g
lucosyltransferase) family of putative regulatory proteins. Using quantitative reverse transcription-PCR, translational
lacZ
fusions, and electrophoretic mobility shift assays, we demonstrate that ElrR positively regulates expression of
elrA
. These results correlate with the attenuated virulence of the Δ
elrR
strain in a mouse peritonitis model. Virulence of simple and double
elrR
and
elrA
deletion mutants also suggests a remaining ElrR-independent expression of
elrA in vivo
and additional virulence-related genes controlled by ElrR.
Dissecting the Metal Selectivity of MerR Monovalent Metal Ion Sensors in Salmonella
Authors: Ibáñez María M. , Cerminati Sebastián , Checa Susana K. , Soncini Fernando C.
Published: May 2013

Two homologous transcription factors, CueR and GolS, that belong to the MerR metalloregulatory family are responsible for
Salmonella
Cu and Au sensing and resistance, respectively. They share similarities not only in their sequences, but also in their target transcription binding sites. While CueR responds similarly to Au, Ag, or Cu to induce the expression of its target genes, GolS shows higher activation by Au than by Ag or Cu. We showed that the ability of GolS to distinguish Au from Cu resides in the metal-binding loop motif. Here, we identify the amino acids within the motif that determine
in vivo
metal selectivity. We show that residues at positions 113 and 118 within the metal-binding loop are the main contributors to metal selectivity. The presence of a Pro residue at position 113 favors the detection of Cu, while the presence of Pro at position 118 disfavors it. Our results highlight the molecular bases that allow these regulators to coordinate the correct metal ion directing the response to a particular metal injury.
Ubiquinone and Menaquinone Electron Carriers Represent the Yin and Yang in the Redox Regulation of the ArcB Sensor Kinase
Authors: Alvarez Adrián F. , Rodriguez Claudia , Georgellis Dimitris
Published: May 2013

The Arc two-component system, comprising the ArcB sensor kinase and the ArcA response regulator, modulates the expression of numerous genes in response to respiratory growth conditions. Under aerobic growth conditions, the ubiquinone electron carriers were proposed to silence the kinase activity of ArcB by oxidizing two cytosol-located redox-active cysteine residues that participate in intermolecular disulfide bond formation. Here, we confirm the role of the ubiquinone electron carriers as the silencing signal of ArcB
in vivo
, we show that the redox potential of ArcB is about −41 mV, and we demonstrate that the menaquinols are required for proper ArcB activation upon a shift from aerobic to anaerobic growth conditions. Thus, an essential link in the Arc signal transduction pathway connecting the redox state of the quinone pool to the transcriptional apparatus is elucidated.
Quadrivalvular heart disease of mixed congenital and rheumatic aetiology with concomitant ostium secundum atrial septal defect and Ebstein's anomaly of the tricuspid valve
Authors: Shetty Ranjan K , Vivek G , Naha Kushal , Rau N R , Nayak K
Published: May 2013

We describe a 34-year-old man with an ostium secundum atrial septal defect, Ebstein's anomaly of the tricuspid valve with severe tricuspid regurgitation, congenital valvular pulmonary stenosis, rheumatic mitral stenosis and regurgitation with aortic regurgitation, who presented with decompensated heart failure after developing atrial fibrillation. The complex haemodynamic interplay of these lesions is also discussed.
Biopsy-proven drug-induced tubulointerstitial nephritis in a patient with acute kidney injury and alcoholic severe acute pancreatitis
Authors: Yoshioka Wakako , Mori Takayasu , Nagahama Kiyotaka , Tamura Teiichi
Published: May 2013

We report a 49-year-old man with alcoholic severe acute pancreatitis (SAP) complicated by drug-induced acute tubulointerstitial nephritis (DI-AIN). Oliguria persisted and became anuric again on day 17 despite improvement of pancreatitis. He presented rash, fever and eosinophilia from day 20. Renal biopsy was performed for dialysis-dependent acute kidney injury (AKI), DI-AIN was revealed, and prompt use of corticosteroids fully restored his renal function. This diagnosis might be missed because it is difficult to perform renal biopsy in such a clinical situation. If the patient's general condition allows, renal biopsy should be performed and reversible AKI must be distinguished from many cases of irreversible AKI complicated by SAP. This is the first report of biopsy-proven DI-AIN associated with SAP, suggesting the importance of biopsy for distinguishing DI-AIN in persisting AKI of SAP.
Renovascular hypertension in an 8-year-old girl
Authors: Cabral Antonio Jorge , Silvestre Catarina , Loureiro Helena , Almeida Helena Isabel
Published: May 2013

Secondary hypertension is the most common form of hypertension in childhood, particularly in the young age group: parenchymal disease and lesions of the renal artery account for the majority of such cases. Renal artery aneurysms (RAA) are rare and are usually diagnosed by Doppler ultrasonography or angiography performed in the investigation of specific clinical symptoms. We report herein a case of severe arterial hypertension in an 8-year-old girl arising from a large saccular RAA. Intravenous antihypertensive drugs were necessary to achieve blood pressure control and the final diagnosis was obtained from angio-CT scan and selective angiography that demonstrated a large saccular aneurysm of the left renal artery with parietal calcification. After confirmation of inexistent function of the entire left kidney by Tc99m-MAG3 renal isotope scan, nephrectomy was performed. The child's blood pressure further normalised and, 1 month after surgery, she had ceased any antihypertensive therapy.
The incidence of concussion in professional and collegiate ice hockey: are we making progress? A systematic review of the literature
Authors: Ruhe Alexander , Gänsslen Axel , Klein Wolfgang
Published: May 2013

Background

The fast, random nature and characteristics of ice hockey make injury prevention a challenge as high-velocity impacts with players, sticks and boards occur and may result in a variety of injuries, including concussion.

Methods

Five online databases (January 1970 and May 2012) were systematically searched followed by a manual search of retrieved papers.

Results

Seventeen studies met the inclusion criteria. The heterogeneous diagnostic procedures and criteria for concussion prevented a pooling of data. When comparing the injury data of European and North American or Canadian leagues, the latter show a higher percentage of concussions in relation to the overall number of injuries (2–7% compared with 5.3–18.6%). The incidence ranged from 0.2/1000 to 6.5/1000 game-hours, 0.72/1000 to 1.81/1000 athlete-exposures and was estimated at 0.1/1000 practice-hours.

Discussion and conclusions

The included studies indicate a high incidence of concussion in professional and collegiate ice hockey. Despite all efforts there is no conclusive evidence that rule changes or other measures lead to a decrease in the actual incidence of concussions over the last few decades. This review supports the need for standardisation of the diagnostic criteria and reporting protocols for concussion to allow interstudy comparisons in the future.
Online registration of monthly sports participation after anterior cruciate ligament injury: a reliability and validity study
Authors: Grindem Hege , Eitzen Ingrid , Snyder-Mackler Lynn , Risberg May Arna
Published: May 2013

Background

The current methods measuring sports activity after anterior cruciate ligament (ACL) injury are commonly restricted to the most knee-demanding sports, and do not consider participation in multiple sports. We therefore developed an online activity survey to prospectively record the monthly participation in all major sports relevant to our patient-group.

Objective

To assess the reliability, content validity and concurrent validity of the survey and to evaluate if it provided more complete data on sports participation than a routine activity questionnaire.

Methods

145 consecutively included ACL-injured patients were eligible for the reliability study. The retest of the online activity survey was performed 2 days after the test response had been recorded. A subsample of 88 ACL-reconstructed patients was included in the validity study. The ACL-reconstructed patients completed the online activity survey from the first to the 12th postoperative month, and a routine activity questionnaire 6 and 12 months postoperatively.

Results

The online activity survey was highly reliable (κ ranging from 0.81 to 1). It contained all the common sports reported on the routine activity questionnaire. There was a substantial agreement between the two methods on return to preinjury main sport (κ=0.71 and 0.74 at 6 and 12 months postoperatively). The online activity survey revealed that a significantly higher number of patients reported to participate in running, cycling and strength training, and patients reported to participate in a greater number of sports.

Conclusions

The online activity survey is a highly reliable way of recording detailed changes in sports participation after ACL injury. The findings of this study support the content and concurrent validity of the survey, and suggest that the online activity survey can provide more complete data on sports participation than a routine activity questionnaire.
Injuries affect team performance negatively in professional football: an 11-year follow-up of the UEFA Champions League injury study
Authors: Hägglund Martin , Waldén Markus , Magnusson Henrik , Kristenson Karolina , Bengtsson Håkan , Ekstrand Jan
Published: May 2013

Background

The influence of injuries on team performance in football has only been scarcely investigated.

Aim

To study the association between injury rates and team performance in the domestic league play, and in European cups, in male professional football.

Methods

24 football teams from nine European countries were followed prospectively for 11 seasons (2001–2012), including 155 team-seasons. Individual training and match exposure and time-loss injuries were registered. To analyse the effect of injury rates on performance, a Generalised Estimating Equation was used to fit a linear regression on team-level data. Each team's season injury rate and performance were evaluated using its own preceding season data for comparison in the analyses.

Results

7792 injuries were reported during 1 026 104 exposure hours. The total injury incidence was 7.7 injuries/1000 h, injury burden 130 injury days lost/1000 h and player match availability 86%. Lower injury burden (p=0.011) and higher match availability (p=0.031) were associated with higher final league ranking. Similarly, lower injury incidence (p=0.035), lower injury burden (p<0.001) and higher match availability (p<0.001) were associated with increased points per league match. Finally, lower injury burden (p=0.043) and higher match availability (p=0.048) were associated with an increase in the Union of European Football Association (UEFA) Season Club Coefficient, reflecting success in the UEFA Champions League or Europa League.

Conclusions

Injuries had a significant influence on performance in the league play and in European cups in male professional football. The findings stress the importance of injury prevention to increase a team's chances of success.