bluuebunny/crossref_metadata_2025 huggingface dataset:
Candidates for Symbiotic Control of Sugarcane White Leaf Disease
Authors: Wangkeeree Jureemart , Miller Thomas A. , Hanboonsong Yupa
Published: July 2012

The leafhopper
Matsumuratettix hiroglyphicus
(Matsumura) is the most important vector of a phytoplasma pathogen causing sugarcane white leaf (SCWL) disease. The purpose of this study was to evaluate candidate bacterial symbionts for possible use as vehicles in the control of the disease. 16S rRNA bacterial genes were amplified from whole bodies of
M. hiroglyphicus
leafhoppers and analyzed by cloning and sequencing. Two dominant groups were found: one belonged to the
Betaproteobacteria
that did not closely match any sequences in the database and was named bacterium associated with
M. hiroglyphicus
(BAMH). Another one found to be abundant in this leafhopper is “
Candidatus
Sulcia muelleri” in the order
Bacteroidetes
, which was previously reported in the insect members of the Auchenorrhyncha. Most
M. hiroglyphicus
leafhoppers carry both BAMH and “
Ca
. Sulcia muelleri.” Fluorescent
in situ
hybridization showed that BAMH and “
Ca
. Sulcia muelleri” colocalized in the same bacteriomes. BAMH was present in the midgut and ovaries of the leafhopper and was found in all developmental stages, including eggs, nymphs, and adults. Because BAMH appears to be specific for the SCWL vector, we evaluated it as a candidate for symbiotic control of sugarcane white leaf disease.
The Small Interfering RNA Pathway Is Not Essential for Wolbachia-Mediated Antiviral Protection in Drosophila melanogaster
Authors: Hedges Lauren M. , Yamada Ryuichi , O'Neill Scott L. , Johnson Karyn N.
Published: July 2012

Wolbachia pipientis
delays RNA virus-induced mortality in
Drosophila
spp. We investigated whether
Wolbachia
-mediated protection was dependent on the small interfering RNA (siRNA) pathway, a key antiviral defense. Compared to
Wolbachia
-free flies, virus-induced mortality was delayed in
Wolbachia
-infected flies with loss-of-function of siRNA pathway components, indicating that
Wolbachia
-mediated protection functions in the absence of the canonical siRNA pathway.
Characterization of Osmotically Induced Filaments of Salmonella enterica
Authors: Pratt Zachary L. , Chen Bingming , Czuprynski Charles J. , Wong Amy C. L. , Kaspar Charles W.
Published: July 2012

Salmonella enterica
forms aseptate filaments with multiple nucleoids when cultured in hyperosmotic conditions. These osmotic-induced filaments are viable and form single colonies on agar plates even though they contain multiple genomes and have the potential to divide into multiple daughter cells. Introducing filaments that are formed during osmotic stress into culture conditions without additional humectants results in the formation of septa and their division into individual cells, which could present challenges to retrospective analyses of infectious dose and risk assessments. We sought to characterize the underlying mechanisms of osmotic-induced filament formation. The concentration of proteins and chromosomal DNA in filaments and control cells was similar when standardized by biomass. Furthermore, penicillin-binding proteins in the membrane of salmonellae were active
in vitro
. The activity of penicillin-binding protein 2 was greater in filaments than in control cells, suggesting that it may have a role in osmotic-induced filament formation. Filaments contained more ATP than did control cells in standardized cell suspensions, though the levels of two F
0
F
1
-ATP synthase subunits were reduced. Furthermore, filaments could septate and divide within 8 h in 0.2× Luria-Bertani broth at 23°C, while nonfilamentous control cells did not replicate. Based upon the ability of filaments to septate and divide in this diluted broth, a method was developed to enumerate by plate count the number of individual, viable cells within a population of filaments. This method could aid in retrospective analyses of infectious dose of filamented salmonellae.
Transposon Mutagenesis of Planctomyces limnophilus and Analysis of a
pckA
Mutant
Authors: Schreier Harold J. , Dejtisakdi Wipawee , Escalante Jose Ortega , Brailo Marina
Published: July 2012

A
Planctomyces limnophilus
mutant generated using the EZ-Tn5 transposome was found to possess an insertion within
pckA
, encoding phosphoenolpyruvate carboxykinase. Disruption of
pckA
expression and elimination of enzymatic activity resulted in poor growth in glucose-free medium, demonstrating a gluconeogenic role for
pckA
in
P. limnophilus
.
NsdC and NsdD Affect Aspergillus flavus Morphogenesis and Aflatoxin Production
Authors: Cary Jeffrey W. , Harris-Coward Pamela Y. , Ehrlich Kenneth C. , Mack Brian M. , Kale Shubha P. , Larey Christy , Calvo Ana M.
Published: July 2012

The transcription factors NsdC and NsdD are required for sexual development inAspergillus nidulans. We now show these proteins also play a role in asexual development in the agriculturally important aflatoxin (AF)-producing fungusAspergillus flavus. We found that both NsdC and NsdD are required for production of asexual sclerotia, normal aflatoxin biosynthesis, and conidiophore development. Conidiophores innsdCandnsdDdeletion mutants had shortened stipes and altered conidial heads compared to those of wild-typeA. flavus. Our results suggest that NsdC and NsdD regulate transcription of genes required for early processes in conidiophore development preceding conidium formation. As the cultures aged, the ΔnsdCand ΔnsdDmutants produced a dark pigment that was not observed in the wild type. Gene expression data showed that although AflR is expressed at normal levels, a number of aflatoxin biosynthesis genes are expressed at reduced levels in bothnsdmutants. Expression ofaflD,aflM, andaflPwas greatly reduced innsdCmutants, and neither aflatoxin nor the proteins for these genes could be detected. Our results support previous studies showing that there is a strong association between conidiophore and sclerotium development and aflatoxin production inA. flavus.
Mitochondrial Carnitine-Dependent Acetyl Coenzyme A Transport Is Required for Normal Sexual and Asexual Development of the Ascomycete Gibberella zeae
Authors: Son Hokyoung , Min Kyunghun , Lee Jungkwan , Choi Gyung Ja , Kim Jin-Cheol , Lee Yin-Won
Published: July 2012

Fungi have evolved efficient metabolic mechanisms for the exact temporal (developmental stages) and spatial (organelles) production of acetyl coenzyme A (acetyl-CoA). We previously demonstrated mechanistic roles of several acetyl-CoA synthetic enzymes, namely, ATP citrate lyase and acetyl-CoA synthetases (ACSs), in the plant-pathogenic fungusGibberella zeae. In this study, we characterized two carnitine acetyltransferases (CATs; CAT1 and CAT2) to obtain a better understanding of the metabolic processes occurring inG. zeae. We found that CAT1 functioned as an alternative source of acetyl-CoA required for lipid accumulation in anACS1deletion mutant. Moreover, deletion ofCAT1and/orCAT2resulted in various defects, including changes to vegetative growth, asexual/sexual development, trichothecene production, and virulence. Although CAT1 is associated primarily with peroxisomal CAT function, mislocalization experiments showed that the role of CAT1 in acetyl-CoA transport between the mitochondria and cytosol is important for sexual and asexual development inG. zeae. Taking these data together, we concluded thatG. zeaeCATs are responsible for facilitating the exchange of acetyl-CoA across intracellular membranes, particularly between the mitochondria and the cytosol, during various developmental stages.
Multifunctional G-Rich and RRM-Containing Domains of TbRGG2 Perform Separate yet Essential Functions in Trypanosome RNA Editing
Authors: Foda Bardees M. , Downey Kurtis M. , Fisk John C. , Read Laurie K.
Published: July 2012

Efficient editing of
Trypanosoma brucei
mitochondrial RNAs involves the actions of multiple accessory factors.
T. brucei
RGG2 (TbRGG2) is an essential protein crucial for initiation and 3′-to-5′ progression of editing. TbRGG2 comprises an N-terminal G-rich region containing GWG and RG repeats and a C-terminal RNA recognition motif (RRM)-containing domain. Here, we perform
in vitro
and
in vivo
separation-of-function studies to interrogate the mechanism of TbRGG2 action in RNA editing. TbRGG2 preferentially binds preedited mRNA
in vitro
with high affinity attributable to its G-rich region. RNA-annealing and -melting activities are separable, carried out primarily by the G-rich and RRM domains, respectively.
In vivo
, the G-rich domain partially complements TbRGG2 knockdown, but the RRM domain is also required. Notably, TbRGG2's RNA-melting activity is dispensable for RNA editing
in vivo
. Interactions between TbRGG2 and MRB1 complex proteins are mediated by both G-rich and RRM-containing domains, depending on the binding partner. Overall, our results are consistent with a model in which the high-affinity RNA binding and RNA-annealing activities of the G-rich domain are essential for RNA editing
in vivo
. The RRM domain may have key functions involving interactions with the MRB1 complex and/or regulation of the activities of the G-rich domain.
AdeR, a PucR-Type Transcription Factor, Activates Expression of l-Alanine Dehydrogenase and Is Required for Sporulation of Bacillus subtilis
Authors: Lin Ta-Hui , Wei Guei-Tsung , Su Chien-Chen , Shaw Gwo-Chyuan
Published: July 2012

TheBacillus subtilis aldgene encodesl-alanine dehydrogenase, which catalyzes the NAD+-dependent deamination ofl-alanine to pyruvate for the generation of energy and is required for normal sporulation. The transcription ofaldis induced by alanine, but the mechanism underlying alanine induction remains unknown. Here we report that a gene (formerlyyukFand now designatedadeR) located upstream ofaldis essential for the basal and alanine-inducible expression ofald. The disruption of theadeRgene caused a sporulation defect, whereas the complementation of anadeRmutation with an intactadeRgene restored the sporulation ability.adeRexpression was not subject to autoregulation and alanine induction. Deletion and mutation analyses revealed that an inverted repeat, centered at position −74.5 relative to the transcriptional initiation site ofald, was required foraldexpression and also likely served as a ρ-independent transcription terminator. Electrophoretic mobility shift assays showed that purified His-tagged AdeR was a specific DNA-binding protein and that this inverted repeat was required for AdeR binding. AdeR shows no significant amino acid sequence similarity to the known transcriptional activators ofaldgenes from other bacteria. AdeR appears to be a member of the PucR family of transcriptional regulators. Its orthologs of unknown function are present in some otherBacillusspecies. Collectively, these findings support the notion that AdeR is a transcriptional activator which mediatesaldexpression in response to alanine availability and is important for normal sporulation inB. subtilis.
The Bacteriophage HK97 gp15 Moron Element Encodes a Novel Superinfection Exclusion Protein
Authors: Cumby Nichole , Edwards Aled M. , Davidson Alan R. , Maxwell Karen L.
Published: July 2012

A phage moron is a DNA element inserted between a pair of genes in one phage genome that are adjacent in other related phage genomes. Phage morons are commonly found within phage genomes, and in a number of cases, they have been shown to mediate phenotypic changes in the bacterial host. The temperate phage HK97 encodes a moron element, gp15, within its tail morphogenesis region that is absent in most closely related phages. We show that gp15 is actively expressed from the HK97 prophage and is responsible for providing the host cell with resistance to infection by phages HK97 and HK75, independent of repressor immunity. To identify the target(s) of this gp15-mediated resistance, we created a hybrid of HK97 and the related phage HK022. This hybrid phage revealed that the tail tube or tape measure proteins likely mediate the susceptibility of HK97 to inhibition by gp15. The N terminus of gp15 is predicted with high probability to contain a single membrane-spanning helix by several transmembrane prediction programs. Consistent with this putative membrane localization, gp15 acts to prevent the entry of phage DNA into the cytoplasm, acting in a manner reminiscent of those of several previously characterized superinfection exclusion proteins. The N terminus of gp15 and its phage homologues bear sequence similarity to YebO proteins, a family of proteins of unknown function found ubiquitously in enterobacteria. The divergence of their C termini suggests that phages have co-opted this bacterial protein and subverted its activity to their advantage.
Transcriptional Regulation of theecpOperon by EcpR, IHF, and H-NS in Attaching and Effacing Escherichia coli
Authors: Martínez-Santos Verónica I. , Medrano-López Abraham , Saldaña Zeus , Girón Jorge A. , Puente José L.
Published: July 2012

Enteropathogenic (EPEC) and enterohemorrhagic (EHEC)Escherichia coliare clinically important diarrheagenic pathogens that adhere to the intestinal epithelial surface. TheE. colicommon pili (ECP), or meningitis-associated and temperature-regulated (MAT) fimbriae, are ubiquitous among both commensal and pathogenicE. colistrains and play a role as colonization factors by promoting the interaction between bacteria and host epithelial cells and favoring interbacterial interactions in biofilm communities. The first gene of theecpoperon encodes EcpR (also known as MatA), a proposed regulatory protein containing a LuxR-like C-terminal helix-turn-helix (HTH) DNA-binding motif. In this work, we analyzed the transcriptional regulation of theecpgenes and the role of EcpR as a transcriptional regulator. EHEC and EPECecpRmutants produce less ECP, while plasmids expressing EcpR increase considerably the expression of EcpA and production of ECP. Theecpgenes are transcribed as an operon from a promoter located 121 bp upstream of the start codon ofecpR. EcpR positively regulates this promoter by binding to two TTCCT boxes distantly located upstream of theecppromoter, thus enhancing expression of downstreamecpgenes, leading to ECP production. EcpR mutants in the putative HTH DNA-binding domain are no longer able to activateecpexpression or bind to the TTCCT boxes. EcpR-mediated activation is aided by integration host factor (IHF), which is essential for counteracting the repression exerted by histone-like nucleoid-structuring protein (H-NS) on theecppromoter. This work demonstrates evidence about the interplay between a novel member of a diverse family of regulatory proteins and global regulators in the regulation of a fimbrial operon.
Hypomorphic Glycosyltransferase Alleles and Recoding at Contingency Loci Influence Glycan Microheterogeneity in the Protein Glycosylation System of Neisseria Species
Authors: Johannessen Camilla , Koomey Michael , Børud Bente
Published: July 2012

As more bacterial protein glycosylation systems are identified and characterized, a central question that arises is, what governs the prevalence of particular glycans associated with them? In addition, accumulating evidence shows that bacterial protein glycans can be subject to the phenomenon of microheterogeneity, in which variant glycan structures are found at specific attachment sites of a given glycoprotein. Although factors underlying microheterogeneity in reconstituted expression systems have been identified and modeled, those impacting natural systems largely remain enigmatic. On the basis of a sensitive and specific glycan serotyping system, microheterogeneity has been reported for the broad-spectrum,O-linked protein glycosylation system in species within the genusNeisseria. To elucidate the mechanisms involved, a genetic approach was used to identify a hypomorphic allele ofpglA(encoding the PglA galactosyltransferase) as a significant contributor to simultaneous expression of multiple glycoforms. Moreover, this phenotype was mapped to a single amino acid polymorphism in PglA. Further analyses revealed that manypglAphase-off variants (containing out-of-frame configurations in simple nucleotide repeats within the open reading frame) were associated with disproportionally high levels of theN,N′-diacetylbacillosamine–Gal disaccharide glycoform generated by PglA. This phenotype is emblematic of nonstandard decoding involving programmed ribosomal frameshifting and/or programmed transcriptional realignment. Together, these findings provide new information regarding the mechanisms of neisserial protein glycan microheterogeneity and the anticipatory nature of contingency loci.
Pseudomonas syringae Catalases Are Collectively Required for Plant Pathogenesis
Authors: Guo Ming , Block Anna , Bryan Crystal D. , Becker Donald F. , Alfano James R.
Published: July 2012

The bacterial pathogenPseudomonas syringaepv. tomato DC3000 must detoxify plant-produced hydrogen peroxide (H2O2) in order to survive in its host plant. Candidate enzymes for this detoxification include the monofunctional catalases KatB and KatE and the bifunctional catalase-peroxidase KatG of DC3000. This study shows that KatG is the major housekeeping catalase of DC3000 and provides protection against menadione-generated endogenous H2O2. In contrast, KatB rapidly and substantially accumulates in response to exogenous H2O2. Furthermore, KatB and KatG have nonredundant roles in detoxifying exogenous H2O2and are required for full virulence of DC3000 inArabidopsis thaliana. Therefore, the nonredundant ability of KatB and KatG to detoxify plant-produced H2O2is essential for the bacteria to survive in plants. Indeed, a DC3000 catalase triple mutant is severely compromised in its ability to growin planta, and its growth can be partially rescued by the expression ofkatB,katE, orkatG. Interestingly, our data demonstrate that although KatB and KatG are the major catalases involved in the virulence of DC3000, KatE can also provide some protectionin planta. Thus, our results indicate that these catalases are virulence factors for DC3000 and are collectively required for pathogenesis.
Cost-effectiveness of a community-based physical activity programme for adults (Be Active) in the UK: an economic analysis within a natural experiment
Authors: Frew Emma J , Bhatti Mobeen , Win Khine , Sitch Alice , Lyon Anna , Pallan Miranda , Adab Peymane
Published: July 2012

Objective

To determine the cost-effectiveness of a physical activity programme (Be Active) aimed at city-dwelling adults living in Birmingham, UK.

Methods

Very little is known about the cost-effectiveness of public health programmes to improve city-wide physical activity rates. This paper presents a cost-effectiveness analysis that compares a physical activity intervention (Be Active) with no intervention (usual care) using an economic model to quantify the reduction in disease risk over a lifetime. Metabolic equivalent minutes achieved per week, quality-adjusted life years (QALYs) gained and healthcare costs were all included as the main outcome measures in the model. A cost-benefit analysis was also conducted using ‘willingness-to-pay’ as a measure of value.

Results

Under base-case assumptions—that is, assuming that the benefits of increased physical activity are sustained over 5 years, participation in the Be Active programme increased quality-adjusted life expectancy by 0.06 years, at an expected discounted cost of £3552, and thus the cost-effectiveness of Be Active is £400 per QALY. When the start-up costs of the programme are removed from the economic model, the cost-effectiveness is further improved to £16 per QALY. The societal value placed on the Be Active programme was greater than the operation cost therefore the Be Active physical activity intervention results in a net benefit to society.

Conclusions

Participation in Be Active appeared to be cost-effective and cost-beneficial. These results support the use of Be Active as part of a public health programme to improve physical activity levels within the Birmingham-wide population.
Individual responses to short-term heat acclimatisation as predictors of football performance in a hot, dry environment
Authors: Racinais Sebastien , Mohr Magni , Buchheit Martin , Voss Sven Christian , Gaoua Nadia , Grantham Justin , Nybo Lars
Published: July 2012

Objectives

To identify the relationship between field performance in a hot environment and individual heat acclimatisation responses in football players.

Methods

Nineteen semiprofessional football players completed a match in 21°C followed by 6 days of acclimatisation in dry heat (38–43°C, 12–30% relative humidity) and a match in ∼43°C. A heat-response test (30 min walk+30 min seated; 44°C) was performed at the beginning and end of the acclimatisation period.

Results

The acclimatisation period increased sweat rate by 34% during a standard heat-exposure test and reduced sweat sodium concentration by 18% (both p≤0.005). Plasma volume changes showed large interindividual differences (−10 to +20%). Match-running performance was impaired in hot ambient condition and demonstrated marked interindividual differences (total distance −6.0±5.8%, high-intensity running −16.4±21.5%, both p≤0.002). Only haematological markers investigated during the heat-response test correlated with the ability of the player to cope with heat stress in a competitive situation; that is, changes in haematocrit between the heat-response tests were correlated to changes in total running during the game, r=−0.75; 90%CI [−0.88 to −0.51].

Conclusions

Heat acclimatisation responses and in turn, match-running performance in the heat, are highly individual. The players displaying the largest haematological adaptations were able to maintain the same activity when playing in the heat as when playing in temperate conditions. As such, team doctors might use acclimatisation indicators obtained from a heat-response test to predict the ability of individual players to cope with heat in competitive situations and individualise their preparation accordingly.
When data are not missing at random: implications for measuring health conditions in the Behavioral Risk Factor Surveillance System
Authors: Frankel Martin R , Battaglia Michael P , Balluz Lina , Strine Tara
Published: July 2012

Objectives

To examine the effect on estimated levels of health conditions produced from large-scale surveys, when either list-wise respondent deletion or standard demographic item-level imputation is employed. To assess the degree to which further bias reduction results from the inclusion of correlated ancillary variables in the item imputation process.

Design

Large cross-sectional (US level) household survey.

Participants

218 726 US adults (18 years and older) in the 2006 Behavioral Risk Factor Surveillance System Survey. This survey is the largest US telephone survey conducted by the Centers for Disease Control and Prevention.

Primary and secondary outcome measures

Estimated rates of severe depression among US adults.

Results

The use of list-wise respondent deletion and/or demographic imputation results in the underestimation of severe depression among adults in the USA. List-wise deletion produces underestimates of 9% (8.7% vs 9.5%). Demographic imputation produces underestimates of 7% (8.9% vs 9.5%). Both of these differences are significant at the 0.05 level.

Conclusion

The use of list-wise deletion and/or demographic-only imputation may produce significant distortion in estimating national levels of certain health conditions.
Understanding factors influencing vulnerable older people keeping warm and well in winter: a qualitative study using social marketing techniques
Authors: Tod Angela Mary , Lusambili Adelaide , Homer Catherine , Abbott Joanne , Cooke Joanne Mary , Stocks Amanda Jayne , McDaid Kathleen Anne
Published: July 2012

Objectives

To understand the influences and decisions of vulnerable older people in relation to keeping warm in winter.

Design

A qualitative study incorporating in-depth, semi-structured individual and group interviews, framework analysis and social marketing segmentation techniques.

Setting

Rotherham, South Yorkshire, UK.

Participants

50 older people (>55) and 25 health and social care staff underwent individual interview. The older people also had household temperature measurements. 24 older people and 19 health and social care staff participated in one of the six group interviews.

Results

Multiple complex factors emerged to explain whether vulnerable older people were able to keep warm. These influences combined in various ways that meant older people were not able to or preferred not to access help or change home heating behaviour. Factors influencing behaviours and decisions relating to use of heating, spending money, accessing cheaper tariffs, accessing benefits or asking for help fell into three main categories. These were situational and contextual factors, attitudes and values, and barriers. Barriers included poor knowledge and awareness, technology, disjointed systems and the invisibility of fuel and fuel payment. Findings formed the basis of a social marketing segmentation model used to develop six pen portraits that illustrated how factors that conspire against older people being able to keep warm.

Conclusions

The findings illustrate how and why vulnerable older people may be at risk of a cold home. The pen portraits provide an accessible vehicle and reflective tool to raise the capacity of the NHS in responding to their needs in line with the Cold Weather Plan.
Effectiveness and safety of metformin in 51 675 patients with type 2 diabetes and different levels of renal function: a cohort study from the Swedish National Diabetes Register
Authors: Ekström Nils , Schiöler Linus , Svensson Ann-Marie , Eeg-Olofsson Katarina , Miao Jonasson Junmei , Zethelius Björn , Cederholm Jan , Eliasson Björn , Gudbjörnsdottir Soffia
Published: July 2012

Objective

To evaluate the effectiveness and safety of metformin use in clinical practice in a large sample of pharmacologically treated patients with type 2 diabetes and different levels of renal function.

Design

Observational study between July 2004 and December 2010, mean follow-up 3.9 years.

Setting

Hospital outpatient clinics and primary care in Sweden.

Participants

51 675 men and women with type 2 diabetes, registered in the Swedish National Diabetes Register, and on continuous glucose-lowering treatment with oral hypoglycaemic agents (OHAs) or insulin.

Main outcome measures

Risks of cardiovascular disease (CVD), all-cause mortality and acidosis/serious infection, associated with each treatment regimens, were analysed in all patients and in subgroups with different estimated glomerular filtration rate (eGFR) intervals. Covariance adjustment and propensity scores were used to adjust for several baseline risk factors and characteristics at Cox regression.

Results

Compared with metformin in monotherapy, HRs for fatal/non-fatal CVD and all-cause mortality with all other OHAs combined (approximately 80% sulphonylureas) in monotherapy were 1.02 (95% CI 0.93 to 1.12) and 1.13 (1.01 to 1.27), while 1.18 (1.07 to 1.29) and 1.34 (1.19 to 1.50) with insulin in monotherapy, adjusting using propensity scores. Metformin, compared with any other treatment, showed reduced risks of acidosis/serious infection (adjusted HR 0.85, 95% CI 0.74 to 0.97) and all-cause mortality (HR 0.87, 95% CI 0.77 to 0.99), in patients with eGFR 45–60 ml/min/1.73 m2, and no increased risks of all-cause mortality, acidosis/serious infection or CVD were found in patients with eGFR 30–45 ml/min/1.73 m2.

Conclusions

Metformin showed lower risk than insulin for CVD and all-cause mortality and slightly lower risk for all-cause mortality compared with other OHA, in these 51 675 patients followed for 4 years. Patients with renal impairment showed no increased risk of CVD, all-cause mortality or acidosis/serious infection. In clinical practice, the benefits of metformin use clearly outbalance the risk of severe side effects.
Proximity to health services and child survival in low- and middle-income countries: a systematic review and meta-analysis
Authors: Okwaraji Yemisrach Behailu , Edmond Karen M
Published: July 2012

Objectives

Few studies have systematically examined the effects of barriers such as distance to health facilities on child survival in low- and middle-income countries. Our primary objective was to estimate the effect of proximity to health facilities on child survival in low- and middle-income countries. The secondary objective was to compare effects in different age categories (perinatal (28 weeks of gestation to 1 week of age), neonatal (0–27 days), infant (0–11 months) and child (0–59 months) mortality).

Design

A systematic review and meta-analysis was conducted of studies published from 1980 to 2012 that assessed the effect of proximity to health facilities on child survival in low- and middle-income countries. Synthesis was by random-effects meta-analysis, and variation between studies was investigated by meta-regression.

Setting

Low- and middle-income countries.

Participants

13 studies were included in the meta-analysis, 11 from low-income and two from middle-income countries and none were from remote areas.

Primary outcome measures

The primary outcome measures of interest were perinatal, neonatal, infant and child mortality.

Results

Overall, children who lived farthest from health facilities were more likely to die compared with those who lived closer (OR 1.32, 95% CI 1.19 to 1.47). This effect appeared stronger during the perinatal (OR 2.76, 95% CI 1.80 to 4.24) and neonatal (OR 1.98, 95% CI 1.43 to 2.72) periods compared with the infant (OR 1.18, 95% CI 1.0 to 1.38) and under-5 (OR 1.20, 95% CI 1.04 to 1.39) periods.

Conclusions

Proximity to health facilities appears to be an important determinant of under-5 mortality in low- and middle-income countries, especially in the perinatal and neonatal periods. Higher quality studies are needed, which examine the effect of access to health services on child survival, especially studies from remote areas and hard to reach populations.
Attitudes and expectations of gastroenterology outpatients about the importance of diet and possible relationship to their symptoms
Authors: Adesokan Akintayo , Neild Penny
Published: July 2012

Objectives

To evaluate gastroenterology outpatients’ attitudes to the importance of diet and its relationship to their symptoms, as well as their expectations of dietary advice from health professionals.

Design

Prospective clinical audit.

Setting

Gastroenterology outpatient department of St George's Healthcare NHS Trust.

Patients

Two hundred and twenty-five patients, aged between 18 and 70 years met the inclusion criteria.

Interventions

None.

Main outcome measures

Participants’ responses to a structured questionnaire.

Results

Sixty-nine per cent of participants felt their diet played an important role in their condition. Factors significantly associated with a positive dietary attitude included younger age (40.6 years vs 46.0 years, p<0.01), regularity of dietary pattern (108 vs 35, p<0.01), number of symptoms (4.6 vs 2.5, p<0.01), severity of gastrointestinal symptoms (2.3 vs 1.5, p<0.01), history of weight loss (34% vs 20.3%, p<0.05) and history of dietary advice (71.1% vs 33.3%, p<0.01). Sixty-eight per cent (68%) of participants were interested in receiving dietary advice, though only 36% expected to receive it. No differences were found for any comparisons based on average body mass index.

Conclusion

The majority of gastroenterology outpatients view diet as playing an important role in their condition, particularly those who have more severe symptoms and those who have received dietary advice. Although a large proportion of patients are interested in receiving dietary advice, few expect to receive it in clinics. Further research is required to explore the reasons why, and to assess the confidence of health professionals in providing nutritional advice.
Otitis media in five cats associated with soft palate abnormalities
Authors: Woodbridge N. T. , Baines E. A. , Baines S. J.
Published: July 2012

The medical records of five cats that were diagnosed with otitis media and soft palate abnormalities, three of which had concurrent otitis interna, were reviewed retrospectively. The animals presented with unilateral or bilateral otitis media or otitis interna associated with soft palate hypoplasia (four cases) or unilateral soft palate cleft (one case). Otitis media was confirmed by radiography, CT or MRI. The soft palate abnormalities present were discovered on oropharyngeal examination at induction of anaesthesia. These five cases provide additional support of a link between otitis media and soft palate abnormalities in cats, as reported in humans and dogs.
Use of fluorescent tagging for assessment of environmental cleaning and disinfection in a veterinary hospital
Authors: Weese J. S. , Lowe T. , Walker M.
Published: July 2012

Environmental cleaning was assessed at a small animal veterinary referral hospital and associated primary healthcare facility. A convenience sample of surfaces was contaminated with fluorescent dye, and then cleaning was assessed 24 hours later by UV light visualisation. Five hundred sixty‐three sites were assessed; however, 70 sites were unable to be evaluated 24 hours later because equipment had been removed or because rooms were occupied at the time of re‐evaluation. Overall, dye was removed from 212/493 (43%) of sites. Site‐specific rates ranged from 14% (computer keyboards and mice, 9/66 site cleaned) to 81% (examination tables, 44/54 sites cleaned). There was a significant difference in the prevalence of successful cleaning by general location (P < 0.0001) and surface type (P < 0.0001). Environmental tagging was an easy and low‐cost tool to assess cleaning practices. Results prompted further infection control investigations to explain selected deficiencies, leading to identification of inadequacies in protocols and practices. Environmental tagging may be a useful infection control tool for establishing baseline cleaning rates, identifying deficiencies in protocols, evaluating the effects of interventions and education of personnel.
Electron Microscopy of Biological Materials at the Nanometer Scale
Authors: Kourkoutis Lena Fitting , Plitzko Jürgen M. , Baumeister Wolfgang
Published: July 2012

Electron microscopy of biological matter uses three different imaging modalities: (a) electron crystallography, (b) single-particle analysis, and (c) electron tomography. Ideally, these imaging modalities are applied to frozen-hydrated samples to ensure an optimal preservation of the structures under scrutiny. Cryo-electron microscopy of biological matter has made important advances in the past decades. It has become a research tool that further expands the scope of structural research into unique areas of cell and molecular biology, and it could augment the materials research portfolio in the study of soft and hybrid materials. This review addresses how researchers using transmission electron microscopy can derive structural information at high spatial resolution from fully hydrated specimens, despite their sensitivity to ionizing radiation, despite the adverse conditions of high vacuum for samples that have to be kept in aqueous environments, and despite their low contrast resulting from weakly scattering building blocks.
Advances in Thermal Conductivity
Authors: Toberer Eric S. , Baranowski Lauryn L. , Dames Chris
Published: July 2012

This review discusses recent advances in materials engineering to control thermal conductivity. We begin by presenting theories of heat conduction for general material classes, focusing on common approximations and trends. Next, we discuss characterization techniques for measuring thermal conductivity and the underlying transport properties. Advanced materials at the frontiers of thermal transport, such as rattlers, complex unit cells, nanowires, and nanocomposites, are treated in depth using experimental data and theoretical predictions. The review closes by highlighting several promising areas for further development.
A Cultural Sociology of Religion: New Directions
Authors: Edgell Penny
Published: July 2012

In this article, I review three contemporary streams of scholarship that are revitalizing the cultural analysis of religion, an approach that dates to the discipline's founding. Research from an institutional field perspective focuses on the institutions that shape religious belief, practice, and mobilization. Work on lived religion, including neo-Durkheimian approaches, focuses on religious experience and contested practices of sacralization. Scholarship on religious cultural tools and symbolic boundaries analyzes religion as symbolic legitimation. These three approaches avoid serious problems associated with both market and secularization accounts, in part because of the way they conceptualize religious authority and religious identity, and in part because of their broader scope of inquiry. In the conclusion, I combine the insights from these approaches to articulate a promising agenda for future research, offering a set of focus questions that are relevant to both classical and contemporary concerns about religion's role in modern societies.
Inhibition of gut- and lung-derived serotonin attenuates pulmonary hypertension in mice
Authors: Abid Shariq , Houssaini Amal , Chevarin Caroline , Marcos Elisabeth , Tissot Claire-Marie , Gary-Bobo Guillaume , Wan Feng , Mouraret Nathalie , Amsellem Valerie , Dubois-Randé Jean-Luc , Hamon Michel , Adnot Serge
Published: July 2012

Decreasing the bioavailability of serotonin (5-HT) by inhibiting its biosynthesis may represent a useful adjunctive treatment of pulmonary hypertension (PH). We assessed this hypothesis using LP533401, which inhibits the rate-limiting enzyme tryptophan hydroxylase 1 (Tph1) expressed in the gut and lung, without inhibiting Tph2 expressed in neurons. Mice treated repeatedly with LP533401 (30–250 mg/kg per day) exhibited marked 5-HT content reductions in the gut, lungs, and blood, but not in the brain. After a single LP533401 dose (250 mg/kg), lung and gut 5-HT contents decreased by 50%, whereas blood 5-HT levels remained unchanged, suggesting gut and lung 5-HT synthesis. Treatment with the 5-HT transporter (5-HTT) inhibitor citalopram decreased 5-HT contents in the blood and lungs but not in the gut. In transgenic SM22-5-HTT+ mice, which overexpress 5-HTT in smooth muscle cells and spontaneously develop PH, 250 mg/kg per day LP533401 or 10 mg/kg per day citalopram for 21 days markedly reduced lung and blood 5-HT levels, right ventricular (RV) systolic pressure, RV hypertrophy, distal pulmonary artery muscularization, and vascular Ki67-positive cells ( P < 0.001). Combined treatment with both drugs was more effective in improving PH-related hemodynamic parameters than either drug alone. LP533401 or citalopram treatment partially prevented PH development in wild-type mice exposed to chronic hypoxia. Lung and blood 5-HT levels were lower in hypoxic than in normoxic mice and decreased further after LP533401 or citalopram treatment. These results provide proof of concept that inhibiting Tph1 may represent a new therapeutic strategy for human PH.
Imaging of the mouse lung with scanning laser optical tomography (SLOT)
Authors: Kellner Manuela , Heidrich Marko , Beigel Rebecca , Lorbeer Raoul-Amadeus , Knudsen Lars , Ripken Tammo , Heisterkamp Alexander , Meyer Heiko , Kühnel Mark Philipp , Ochs Matthias
Published: July 2012

The current study focuses on the use of scanning laser optical tomography (SLOT) in imaging of the mouse lung ex vivo. SLOT is a highly efficient fluorescence microscopy technique allowing rapid scanning of samples of a size of several millimeters, thus enabling volumetric visualization by using intrinsic contrast mechanisms of previously fixed lung lobes. Here, we demonstrate the imaging of airways, blood vessels, and parenchyma from whole, optically cleared mouse lung lobes with a resolution down to the level of single alveoli using absorption and autofluorescence scan modes. The internal structure of the lung can then be analyzed nondestructively and quantitatively in three-dimensional datasets in any preferred planar orientation. Moreover, the procedure preserves the microscopic structure of the lung and allows for subsequent correlative histologic studies. In summary, the current study has shown that SLOT is a valuable technique to study the internal structure of the mouse lung.
Exercise-induced cardiac performance in autoimmune (Type 1) diabetes is associated with a decrease in myocardial diacylglycerol
Authors: Loganathan Rajprasad , Novikova Lesya , Boulatnikov Igor G. , Smirnova Irina V.
Published: July 2012

One of the fundamental biochemical defects underlying the complications of diabetic cardiovascular system is elevation of diacylglycerol (DAG) and its effects on protein kinase C (PKC) signaling. It has been noted that exercise training attenuates poor cardiac performance in Type 1 diabetes. However, the role of PKC signaling in exercise-induced alleviation of cardiac abnormalities in diabetes is not clear. We investigated the possibility that exercise training modulates PKC-βII signaling to elicit its beneficial effects on the diabetic heart. bio-breeding diabetic resistant rats, a model reminiscent of Type 1 diabetes in humans, were randomly assigned to four groups: 1) nonexercised nondiabetic (NN); 2) nonexercised diabetic (ND); 3) exercised nondiabetic; and 4) exercised diabetic. Treadmill training was initiated upon the onset of diabetes. At the end of 8 wk, left ventricular (LV) hemodynamic assessment revealed compromised function in ND compared with the NN group. LV myocardial histology revealed increased collagen deposition in ND compared with the NN group, while electron microscopy showed a reduction in the viable mitochondrial fraction. Although the PKC-βII levels and activity were unchanged in the diabetic heart, the DAG levels were increased. With exercise training, the deterioration of LV structure and function in diabetes was attenuated. Notably, improved cardiac performance in training was associated with a decrease in myocardial DAG levels in diabetes. Exercise-induced benefits on cardiac performance in diabetes may be mediated by prevention of an increase in myocardial DAG levels.
Characterization of Liposarcoma Cell Lines for Preclinical and Biological Studies
Authors: Stratford Eva W. , Castro Russell , Daffinrud Jeanette , Skårn Magne , Lauvrak Silje , Munthe Else , Myklebost Ola
Published: July 2012

Liposarcoma cell lines representin vitromodels for studying disease mechanisms at the cellular level and for preclinical evaluation of novel drugs. To date there are a limited number of well-characterized models available. In this study, nine immortal liposarcoma cell lines were evaluated for tumor-forming ability, stem cell- and differentiation potential, and metastatic potential, with the aim to generate a well-characterized liposarcoma cell line panel. Detailed stem cell and differentiation marker analyses were also performed. Five of the liposarcoma cell lines were tumorigenic, forming tumors in mice. Interestingly, tumor-forming ability correlated with high proliferative capacityin vitro. All the cell lines underwent adipocytic differentiation, but the degree varied. Surprisingly, the expression of stem cell and differentiation markers did not correlate well with function. Overall, the panel contains cell lines suited forin vivoanalyses (LPS141, SA-4, T778, SW872, and LISA-2), for testing novel drugs targeting cancer stem cells (LPS141) and for studying tumor progression and metastasis (T449 and T778).
Using Simulation Modeling to Inform Strategies to Reduce Breast Cancer Mortality in Black Women in the District of Columbia
Authors: Near Aimee M. , Mandelblatt Jeanne S. , Schechter Clyde B. , Stoto Michael A.
Published: July 2012

Background. Black women in the District of Columbia (DC) have the highest breast cancer mortality in the US. Local cancer control planners are interested in how to most efficiently reduce this mortality.Methods. An established simulation model was adapted to reflect the experiences of Black women in DC and estimate the past and future impact of changes in use of screening and adjuvant treatment.Results. The model estimates that the observed reduction in mortality that occurred from 1975 to 2007 attributable to screening, treatment, and both was 20.2%, 25.7%, and 41.0% respectively. The results suggest that, by 2020, breast cancer mortality among Black women in DC could be reduced by 6% more by initiating screening at age 40 versus age 50. Screening annually may also reduce mortality to a greater extent than biennially, albeit with a marked increase in false positive screening rates.Conclusion. This study demonstrates how modeling can provide data to assist local planners as they consider different cancer control policies based on their individual populations.
The Retrograde and Retroperitoneal Totally Laparoscopic Hysterectomy for Endometrial Cancer
Authors: Volpi Eugenio , Bernardini Luca , Ferrero Anna Maria
Published: July 2012

Introduction. We retrospectively report our experience with the utilization of an original procedure for total laparoscopic hysterectomy based on completely retrograde and retroperitoneal technique for surgical staging and treatment of the endometrial cancer. The surgical, financial, and oncological advantages are here discussed.Methods. The technique used here has been based on a combination of a retroperitoneal approach with a retrograde and lateral dissection of the bladder and retrograde culdotomy with variable resection of parametrium. No disposable instruments and no uterine manipulator were utilized.Results. Intraoperative and postoperative complications were observed in 10% of the cases overall. Operative time length and mean haemoglobin drop value results were 129 min and 125 mL, respectively. Most patients were dismissed on days 3–5 from the hospital. Seventy-eight percent of the patients were alive with no evidence of disease at mean followup of 49 months.Conclusions. Our original laparoscopic technique is based on a retroperitoneal approach in order to rapidly control main uterine vessels coagulation, constantly check the ureter, and eventually decide type and site of lymph nodes removal. This procedure has important cost saving implications and the avoidance of uterine manipulator is of matter in case such as these of uterine malignancy.
A Numerical Study on Flow around Nonuniform Porous Fences
Authors: Huang Long-Ming , Chan H. C. , Lee Jung-Tai
Published: July 2012

The effects of a porous fence with a nonuniform porosity on flow fields are investigated numerically. First, an experiment with a non‐uniform porous fence located in a wind tunnel is performed to obtain a reference data set. Then, a numerical model that utilizes the finite volume scheme with a weakly compressible‐flow method to solve the continuity and momentum equations is developed. The numerical simulation is compared to experimental measurements for validation purposes. As a result, the numerical predictions show good agreements with the experimental data. Finally, the numerical investigations of the flow fields around porous fences with various combinations of upper and lower fence porosity are also presented. When the upper porosity is greater than the lower porosity, the Protection Index PI0.1, PI0.3 and PI0.5, representing the adverse sheltering effect, decreases compared to that of the uniform porous fence. When the upper porosity is less than the lower porosity, the PI0.5 increases and the variations of the PI0.1 and PI0.3, depend on the upper porosity, compared to that of the uniform porous fence. The results show that the porous fence with the upper fence porosity εU = 0% and the lower fence porosity εL = 30% gives the best sheltering effect among the porous fences in this study.