bluuebunny/crossref_metadata_2025 huggingface dataset:
Diurnal Lightning Variability over the Maritime Continent: Impact of Low-Level Winds, Cloudiness, and the MJO
Authors: Virts Katrina S. , Wallace John M. , Hutchins Michael L. , Holzworth Robert H.
Published: July 2013

Lightning over the Maritime Continent exhibits a pronounced diurnal cycle. Daytime and evening lightning occurs near coastlines and over mountain slopes, driven by sea and valley breezes. Nocturnal and morning thunderstorms are touched off where land breezes or mountain breezes converge or by gravity waves propagating away from regions of vigorous afternoon convection. In this study, the modulation of the diurnal cycle of lightning and precipitation by 850-hPa winds, cloudiness, and the Madden–Julian oscillation (MJO) is investigated using observations from the World Wide Lightning Location Network (WWLLN) and the Tropical Rainfall Measuring Mission (TRMM) satellite. The 850-hPa wind speed and area-averaged cloudiness are shown to be negatively correlated with day-to-day lightning frequency over land, and thunderstorm occurrence is suppressed windward of, and enhanced leeward of, mountain ranges. Lightning and environmental conditions are similarly related in the MJO. During break periods, the regular diurnal cycle of lightning is enhanced where ambient low-level winds are easterly but abnormally weak—in the Strait of Malacca, over western and southern Borneo and the adjacent seas, and in the region of nocturnal thunderstorms to the west of Sumatra and Java. When the active, cloudy phase of the MJO, accompanied by low-level westerly winds, passes over the Maritime Continent, the regular diurnal cycle of lightning is enhanced leeward (to the east) of the mountains of Java, Borneo, and the Malay Peninsula. The spatial patterns of lightning and rainfall anomalies are broadly similar, but lightning anomalies tend to be more concentrated near coastlines.
Interannual Variability of the Atlantic Hadley Circulation in Boreal Summer and Its Impacts on Tropical Cyclone Activity
Authors: Zhang Gan , Wang Zhuo
Published: July 2013

A novel method was developed to define the regional Hadley circulation (HC) in terms of the meridional streamfunction. The interannual variability of the Atlantic HC in boreal summer was examined using EOF analysis. The leading mode (M1), explaining more than 45% of the variances, is associated with the intensity change of the ITCZ. M1 is significantly correlated to multiple climate factors and has strong impacts on Atlantic tropical cyclone (TC) activity. In the positive (negative) phase of M1, the ITCZ is stronger (weaker) than normal, and more (fewer) TCs form over the main development region (MDR) with a larger (smaller) fraction of storms intensifying into major hurricanes. Analyses showed that the large-scale dynamic and thermodynamic conditions associated with a stronger ITCZ are more favorable for TC activity.

The roles of tropical easterly waves in modulating the Atlantic TC activity are highlighted. In the positive phase of M1, the wave activity is significantly enhanced over the MDR and the Caribbean Sea, which can be attributed to stronger coastal convection and mean flow structure changes. In the context of the recently proposed marsupial paradigm, the frequency and structure of wave pouches were examined. In the positive phase of M1, the pouch frequency increases, and the number of pouches with a vertically coherent structure also rises significantly. A deep and vertically aligned wave pouch has been shown to be highly favorable for TC formation.

The HC perspective thus unifies both dynamic and thermodynamic conditions impacting Atlantic TC activity and helps explain the statistical linkages between Atlantic TC activity and different climate factors.
Exploring Successful Principalship in South Africa: A Case Study
Authors: Steyn GM
Published: July 2013

In line with international studies, this study reports in a case study how a South African school principal succeeded in sustaining leadership despite the challenges South African schools experience, and how the principal’s leadership practice related to core leadership practices required for a school principal to be successful. Data were collected by means of open-ended interviews with the principal and his staff. The following main themes were constructed: (1) Personal traits; (2) Leadership style; and (3) Ability to sustain and improve development. Secondary empirical data from previous studies in the school supported the findings in this study. The findings of this case study have implications for South African school principals: (1) principals need to be fully committed to improve the quality of learning in schools; (2) they need to be skilful in effectively using available resources; (3) successful principalship develops over time and requires a clear vision, optimism, high performance expectations and acting with care and integrity to nurture trust among role players.
Does Topical Anesthesia Using Aerosolized Lidocaine Inhibit the Superior Laryngeal Nerve Reflex?
Authors: Arslan Ilker Burak , Kose Isil , Ciger Ejder , Demirhan Erhan , Gumussoy Murat , Cukurova Ibrahim
Published: July 2013

Objective

This study was designed to evaluate the effectiveness of topical lidocaine in attenuating the laryngeal reflex and blunting hemodynamic response by inhibition of the superior laryngeal nerve in laryngeal microsurgery, which would be helpful in preventing potential complications.

Study Design

A prospective, randomized, double‐blind study.

Setting

Tertiary medical center.

Subjects and Methods

Fifty‐four patients requiring glottic and supraglottic laryngeal microsurgery were randomly assigned to 1 of 2 groups, with equal numbers. Before surgery, 10% lidocaine was topically applied to the laryngeal surface of the epiglottis and vocal folds under direct vision in the study group and saline aerosol was applied in the control group. Heart rates, arterial blood pressure, and SPO2 were recorded at baseline, after induction, immediately before and after intubation, during the surgery, and upon extubation. Laryngospasm, agitation, and coughing were recorded during the recovery period.

Results

Heart rates, arterial pressure, and SPO2 did not differ significantly from baseline to postintubation period among the groups. SPO2 values measured similar in the remaining study. Heart rates and blood pressures were slightly decreased in the study group after lidocaine administration, but only blood pressure at pre‐ and post‐extubation was significantly decreased in the study group (P <. 05). Also laryngospasm and coughing were not statistically different between the 2 groups. There was an obvious gap between the 2 groups for agitation. Study group agitation was noted significantly lower (P <. 05).

Conclusion

These findings indicate that preoperative topical lidocaine application may be helpful in attenuating airway‐circulatory reflexes in laryngeal microscopic surgery.
Positional Dependency and Surgical Success of Relocation Pharyngoplasty among Patients with Severe Obstructive Sleep Apnea
Authors: Li Hsueh‐Yu , Cheng Wen‐Nuan , Chuang Li‐Pang , Fang Tuan‐Jen , Hsin Li‐Jen , Kang Chung‐Jan , Lee Li‐Ang
Published: July 2013

Objective

To examine the effect of positional dependency on surgical success among patients with severe obstructive sleep apnea (OSA) following modified uvulopalatopharyngoplasty, known as relocation pharyngoplasty.

Study Design

Case series with planned data collection.

Setting

Tertiary referred center.

Subjects and Methods

Standard nocturnal polysomnography was used to compare the apnea‐hypopnea index (AHI) in different sleep positions before and after relocation pharyngoplasty in 47 consecutive patients with severe OSA (AHI, 59.5 ± 18.2 events/hour; Epworth Sleepiness Scale [ESS] scores, 12.2 ± 4.4) who failed continuous positive airway pressure therapy. Positional (dependency) OSA was defined when the supine:non‐supine AHI ratio was >2, otherwise it was defined as nonpositional OSA. Surgical success was defined as a ≥50% reduction in AHI and a postoperative AHI of ≤20 events/hour. Polysomnographic parameters, ESS, and surgical success following surgery were recorded.

Results

Of the 47 patients, 27 (57%) had positional OSA and 20 (43%) nonpositional OSA. The nonpositional OSA patients had higher AHI and ESS scores than the positional OSA patients (P =. 002 and. 104, respectively). Relocation pharyngoplasty significantly improved AHI and ESS scores in both positional and nonpositional OSA groups 6 months postoperatively (P <. 05). The overall surgical success rate was 49%; however, positional OSA patients had a significantly higher success rate than nonpositional OSA patients (67% vs 25%, P =. 008).

Conclusion

The presence of positional dependency at baseline was a favorable outcome predictor of surgical success among severe OSA patients undergoing relocation pharyngoplasty.
The effectiveness of aquatic physical therapy in the treatment of fibromyalgia: a systematic review with meta-analysis
Authors: Lima Tarcisio Brandão , Dias Josilainne Marcelino , Mazuquin Bruno Fles , da Silva Carla Tassiana , Nogueira Regiane Mazzarioli Pereira , Marques Amélia Pasqual , Lavado Edson Lopes , Cardoso Jefferson Rosa
Published: July 2013

Objective:

To assess the effectiveness of aquatic physical therapy in the treatment of fibromyalgia.

Data sources:

The search strategy was undertaken using the following databases, from 1950 to December 2012: MEDLINE, EMBASE, CINAHL, LILACS, SCIELO, WEB OF SCIENCE, SCOPUS, SPORTDiscus, Cochrane Library Controlled Trials Register, Cochrane Disease Group Trials Register, PEDro and DARE.

Review methods:

The studies were separated into groups: Group I – aquatic physical therapy × no treatment, Group II – aquatic physical therapy × land-based exercises and Group III – aquatic physical therapy × other treatments.

Results:

Seventy-two abstracts were found, 27 of which met the inclusion criteria. For the functional ability (Fibromyalgia Impact Questionnaire), three studies were considered with a treatment time of more than 20 weeks and a mean difference (MD) of −1.35 [−2.04; −0.67], P = 0.0001 was found in favour of the aquatic physical therapy group versus no treatment. The same results were identified for stiffness and the 6-minute walk test where two studies were pooled with an MD of −1.58 [−2.58; −0.58], P = 0.002 and 43.5 (metres) [3.8; 83.2], P = 0.03, respectively.

Conclusion:

Three meta-analyses showed statistically significant results in favour of the aquatic physical therapy (Fibromyalgia Impact Questionnaire, stiffness and the 6-minute walk test) during a period of longer than 20 weeks. Due to the low methodological rigor, the results were insufficient to demonstrate statistical and clinical differences in most of the outcomes.
Prevalence, awareness, treatment and control of hypertension among adults in rural north-western China: a cross-sectional population survey
Authors: Dong Caixia , Ge Pengfei , Ren Xiaolan , Fan Haoqiang , Yan Xiang
Published: July 2013

Objective

To assess rates and determinants of prevalence, awareness, treatment and control of hypertension in rural north-western China.

Methods

Adults were recruited from five surveillance areas in Gansu Province using a three-stage cluster sampling plan. A combination of household and community–based surveys was employed and two methods of surveillance (questionnaire and physical measurement) were undertaken.

Results

A total of 3000 subjects were included; 1100 (36.7%) had hypertension. Hypertension was associated with older age, lower educational levels and being overweight or obese. Only 407 (37%) subjects with hypertension were aware of their condition. Multiple logistic regression showed significant correlations between hypertension awareness and age, obesity and central obesity. Antihypertensive treatment was received by 31.2% of participants with hypertension. Obesity, smoking and older age were associated with treatment. Blood pressure was controlled in 18.1% of participants receiving antihypertensive treatment and in 5.6% of subjects with hypertension overall.

Conclusion

In conclusion, prevalence of hypertension is rapidly increasing in rural north-western China. Rates of awareness and treatment of hypertension remain low and blood pressure is poorly controlled.
The British counter-insurgency myth
Authors: Newsinger John
Published: July 2013

The British Army has an unjustified reputation for expertise and moderation in postwar counter-insurgency operations. David French in The British Way in Counter-Insurgency 1945–1967 and Andrew Mumford in The Counter-Insurgency Myth both demolish that reputation. French uses extensive evidence to reveal the consistent use of tactics of coercion and terror to fight insurgency, while the British public were fed lies about ‘winning hearts and minds’, in what has all the hallmarks of a standard work. Mumford’s approach is more journalistic and, while informed by an urgent awareness of globalised conflict, he fails to draw the obvious conclusion from the dismal history of British counter-insurgency operations he recounts, namely that there should be no more of these costly and damaging military adventures.
Leadership and transformational change in healthcare organisations: A qualitative analysis of the North East Transformation System
Authors: Erskine Jonathan , Hunter David J , Small Adrian , Hicks Chris , McGovern Tom , Lugsden Ed , Whitty Paula , Steen Nick , Eccles Martin Paul
Published: July 2013

The research project ‘An Evaluation of Transformational Change in NHS North East’ examines the progress and success of National Health Service (NHS) organisations in north east England in implementing and embedding the North East Transformation System (NETS), a region-wide programme to improve healthcare quality and safety, and to reduce waste, using a combination of Vision, Compact, and Lean-based Method. This paper concentrates on findings concerning the role of leadership in enabling tranformational change, based on semi-structured interviews with a mix of senior NHS managers and quality improvement staff in 14 study sites. Most interviewees felt that implementing the NETS requires committed, stable leadership, attention to team-building across disciplines and leadership development at many levels. We conclude that without senior leader commitment to continuous improvement over a long time scale and serious efforts to distribute leadership tasks to all levels, healthcare organisations are less likely to achieve positive changes in managerial-clinical relations, sustainable improvements to organisational culture and, ultimately, the region-wide step change in quality, safety and efficiency that the NETS was designed to deliver.
Fault tree analysis for composite structural damages
Authors: Chen Xi , Ren He , Bil Cees
Published: July 2013

Composite airframes suffer from complex damage modes during operation. Many investigations tend to look into specific aspects of damage mechanisms but seldom take a systematic view. This paper introduces a new fault tree methodology to synthesize various damage modes of composite structures by identifying possible damage causes. Qualitative analysis is performed incorporating structure importance analysis, probability importance analysis and relative probability importance analysis. Quantitative analysis by Monte Carlo simulation is then conducted as a validation to demonstrate the feasibility of the fault tree for composite damages. A number of options addressing main damage causes are proposed to improve the reliability of composite structures. Engineers from airlines and manufacturers can use this method to prioritize the main damage causes in different situations as a failure preventative tool or damage evaluation. Also, this approach can be extended to provide valuable inputs to other advanced methodologies to perform better diagnosis and prognosis for composites.
One Without the Other
Authors: Mourey James A. , Oyserman Daphna , Yoon Carolyn
Published: July 2013

People often make multiple choices at the same time, choosing a snack and drink or a cell phone and case, only to learn that some of their choices are unavailable. Do they take the available item (or items) or something else entirely? Culture-as-situated-cognition theory predicts that this choice is determined by one’s accessible cultural mind-set. An accessible collectivist (vs. individualist) mind-set should heighten sensitivity to an emergent relationship among items chosen together so that having some is not acceptable if not all can be obtained. Indeed, we found that Latinos (but not Anglos) refuse chosen items if not all can be obtained (Study 1a). Further, making a collectivist mind-set accessible reproduces this between-groups difference (Study 1b), increases people’s willingness to pay to complete sets (Study 1b), and shifts choice to previously undesired items if no set-completing option is provided (Studies 2–4). Finally, we found that increased sensitivity to an emergent relationship among chosen items mediates these effects (Studies 3 and 4).
Mitochondrial electron transport chain complexes, catalase and markers of oxidative stress in platelets of patients with severe aluminum phosphide poisoning
Authors: Anand R. , Sharma D.R. , Verma D. , Bhalla A. , Gill K.D. , Singh S.
Published: July 2013

Aluminum phosphide (ALP), a widely used fumigant and rodenticide, leads to high mortality if ingested. Its toxicity is due to phosphine that is liberated when it comes in contact with moisture. The exact site or mechanism of action of phosphine is not known, although it is widely believed that it affects mitochondrial oxidative phosphorylation. Basic serum biochemical parameters, activity of mitochondrial complexes, antioxidant enzymes and parameters of oxidative stress were estimated in the platelets of 21 patients who developed severe poisoning following ALP ingestion. These parameters were compared with 32 healthy controls and with 22 patients with shock due to other causes (cardiogenic shock (11), septic shock (9) and hemorrhagic shock (2)). The serum levels of creatine kinase-muscle brain and lactate dehydrogenase were higher in patients poisoned with ALP, whereas a significant decrease was observed in the activities of mitochondrial complexes I, II and IV. The activity of catalase was lower but the activities of superoxide dismutase and glutathione peroxidase were unaffected in them. A significant increase in lipid peroxidation and protein carbonylation was observed, whereas total blood thiol levels were lower. In patients severely poisoned with ALP, not only cytochrome c oxidase but also other complexes are involved in mitochondrial electron transport, and enzymes are also inhibited.
Podoplanin and Clusterin Are Reliable Markers of Nonneoplastic Synovium at Various Sites
Authors: Talmon Geoffrey , Wake Laura , Muirhead David
Published: July 2013

Introduction. Clusterin (CLU) has been noted to mark synovium adjacent to tenosynovial tumors, and studies suggest that podoplanin (PP) is upregulated in inflammatory arthritis. Characterization of synovial staining with CLU and PP in various nonneoplastic disease states has not been described. Methods. A microarray was created from paraffin-embedded human synovium, including 19 normal/noninflammatory (10 weight-bearing joints, 8 non-weight-bearing joints), 9 rheumatoid arthritis, 10 synovial cysts, and 3 osteoarthritis and stained with PP (D2-40) and CLU. Staining intensity was graded semiquantitatively (0-3+). Results. PP and CLU stained synovium in 88% and 95% cases, respectively. PP and CLU showed moderate to strong (3+) staining in 26% and 19% of noninflammatory and 44% and 0% of inflammatory synovia, respectively ( P < .01). Conclusions. PP and CLU are reliable markers of human synovium and can confirm its presence in limited specimens. Although CLU was more sensitive, PP may be more useful in the setting of chronic inflammation.
Renal Anastomosing Hemangiomas With a Diverse Morphologic Spectrum
Authors: Chou Shaun , Subramanian Vishnu , Lau Howard M. H. , Achan Anita
Published: July 2013

Benign vascular lesions have a diverse appearance and can be extremely difficult to classify. We present renal anastomosing hemangiomas from 2 patients that exemplify the potential diverse range of appearances that can occur in this recently described, rare variant of capillary hemangioma. The lesion from one patient was an intravenous hemangioma with closely packed, fenestrated vascular channels that were reminiscent of the splenic red pulp. Also, the endothelial cells contained hyaline globules. On the other hand, the second patient had multifocal tumor. The lesions showed more extensive hyalinization and vascular ectasia reminiscent of cavernous hemangioma. Extramedullary hematopoiesis was a feature in all the tumors, particularly in the second patient where numerous immature blasts were present within vascular spaces.
Large-amplitude vibration of the geometrically imperfect FGM truncated conical shell
Authors: Sofıyev AH , Kuruoglu N
Published: July 2013

In this study, the large-amplitude vibration of a functionally graded (FG) truncated conical shell with an initial geometric imperfection has been investigated using large deformation theory with a von Karman–Donnell type of kinematic nonlinearity. The material properties of an FG truncated conical shell are assumed to vary continuously through the thickness. The fundamental relations, the modified Donnell-type nonlinear motion, and compatibility equations of the FG truncated conical shell with an initial geometric imperfection are derived. The relation between nonlinear frequency parameters with the dimensionless amplitude of imperfect FG truncated conical shells is obtained. Finally, the influences of variations of the initial geometric imperfection, compositional profiles, and shell characteristics on the dimensionless nonlinear frequency parameter and frequency–amplitude relations are investigated. The present results are compared with the available data for a special case.
Active control of hypersonic airfoil flutter via adaptive fuzzy sliding mode method
Authors: Wang Yuhui , Zhang Qiang , Zhu Liang
Published: July 2013

This paper presents a novel adaptive active control method, which is used for the flutter suppression problem in hypersonic flow. First, the system’s stability is analyzed and the Hopf bifurcation points are obtained. Then, fuzzy systems are employed to approximate the system’s nonlinear dynamics. Furthermore, in order to increase the robustness of the system, a sliding surface is designed by introducing an integral operator. Thirdly, by Lyapunov theory, the proposed fuzzy sliding mode active control guarantees the convergence of flutter and the global boundedness of all the signals in the closed-loop system. The simulation results demonstrate the effectiveness of the proposed method.
Investigation on zero-gravity behavior of particle dampers
Authors: Yao B , Chen Q
Published: July 2013

The simulation study of particle damping in microgravity or zero-gravity environments is carried out using the Discrete Element Method in this paper. The results show that the damping particles in zero-gravity environments have a reasonable damping performance only when the particle container is almost fully filled with particles and at large displacement amplitude. The damper will have little effect because the particles will come together and form a floating cluster in the middle of the container, if the vibration amplitude is less than half of the gap between the particle bed and the ends of the container. To break that floating cluster, a cross-shaped spoiler is introduced and fitted inside the container, which greatly raises the damping performance in zero-gravity environments.
Somatic symptoms in those with performance and interaction anxiety
Authors: May Anna C , Rudy Brittany M , Davis Thompson E , Jenkins Whitney S , Reuther Erin T , Whiting Sara E
Published: July 2013

This study ( n = 304) examined the relationship between somatic symptoms and social anxiety. Significant differences in the experience of somatic symptoms were found among four groups (i.e. performance anxious, interaction anxious, generalized socially anxious, and controls). Post hoc analyses revealed that those who exceeded the clinical cutoff for generalized social anxiety exhibited more somatic symptoms than those who exceeded the clinical cutoff in the other two social anxiety domains or controls. Individuals in each group exhibited more somatic symptoms than controls, but subtypes did not differ in the amount of somatic symptoms experienced. Additionally, regression analyses revealed that type of somatic symptoms experienced varied depending on subtype.
Spontaneous bilateral carotid artery dissection in a patient with bovine aortic arch
Authors: Cock Dries De , Meuris Bart , Benett Johan , Desmet Walter
Published: July 2013

Carotid artery dissections are commonly associated with trauma or various connective tissue disorders. Dissection of the cerebrovascular arteries can result in ischemic stroke and is a frequent stroke etiology in younger patients. Anatomical variants of aortic arch branching, such as the ‘bovine’ aortic arch, are assumed to have little or no physiological consequence. To the best of our knowledge, we present for the first time a case of spontaneous dissection of the common origin of the innominate and left common carotid artery in a bovine aortic arch, resulting in bilateral dissection of the carotid arteries.
Conducting ethical research with correctional populations: Do researchers and IRB members know the federal regulations?
Authors: Johnson Mark E , Brems Christiane , Hanson Bridget L , Corey Staci L , Eldridge Gloria D , Mitchell Kristen
Published: July 2013

Conducting or overseeing research in correctional settings requires knowledge of specific federal rules and regulations designed to protect the rights of individuals in incarceration. To investigate the extent to which relevant groups possess this knowledge, using a 10-item questionnaire, we surveyed 885 IRB prisoner representatives, IRB members and chairs with and without experience reviewing HIV/AIDS correctional protocols, and researchers with and without correctional HIV/AIDS research experience. Across all groups, respondents answered 4.5 of the items correctly. Individuals who have overseen or conducted correctional research had the highest scores; however, even these groups responded correctly only to slightly more than half of the items. These findings emphasize the need for ongoing training in federal guidelines governing correctional research, particularly for those individuals who are embarking on this type of research.
The cAMP effector EPAC activates Elk1 transcription factor in prostate smooth muscle, and is a minor regulator of α1-adrenergic contraction
Authors: Hennenberg Martin , Strittmatter Frank , Schmetkamp Henning , Rutz Beata , Walther Sebastian , Stief Christian G , Gratzke Christian
Published: July 2013

Background

Prostate smooth muscle tone is regulated by α1-adrenoceptor-induced contraction and cAMP-mediated relaxation. EPAC is an effector of cAMP, being involved in smooth muscle relaxation and cell cycle control outside the lower urinary tract. Here, we investigated the expression and function of EPAC in human prostate tissues from patients undergoing radical prostatectomy.

Results

mRNA and protein expression of EPAC was detected in all prostate tissues by RT-PCR and Western blot analysis. Immunoreactivity was observed in stromal cells, and colocalized with immunofluorescence for α-smooth muscle actin and calponin. Under normal conditions, noradrenaline- or phenylephrine-induced contraction of prostate strips in the organ bath was not affected by the EPAC activator pCPT (SP-8-pCPT-2′-O-Me-cAMPS.NA) (30 μM). However, when the cyclooxygenase inhibitor indomethacin (50 μM) was added, EPAC activators pCPT and OME (8-CPT-2′-O-Me-cAMP.Na) (30 μM) significantly reduced contractions by low concentrations of phenylephrine. These effects were not observed on noradrenaline-induced contraction. OME and pCPT caused phosphorylation of the transcription factor Elk1 in prostate tissues. Elk1 activation was confirmed by EMSA (electrophoretic mobility shift assay), where OME and pCPT incresed Elk1 binding to a specific DNA probe.

Conclusions

EPAC activation may reduce α1-adrenergic prostate contraction in the human prostate, although this effect is masked by cyclooxygenases and β-adrenoceptors. A main EPAC function in the human prostate may be the regulation of the transcription factor Elk1.
Deciphering the response of Mycobacterium smegmatis to nitrogen stress using bipartite active modules
Authors: Williams Kerstin J , Bryant William A , Jenkins Victoria A , Barton Geraint R , Witney Adam A , Pinney John W , Robertson Brian D
Published: July 2013

Background

The ability to adapt to environments with fluctuating nutrient availability is vital for bacterial survival. Although essential for growth, few nitrogen metabolism genes have been identified or fully characterised in mycobacteria and nitrogen stress survival mechanisms are unknown.

Results

A global transcriptional analysis of the mycobacterial response to nitrogen stress, showed a significant change in the differential expression of 16% of the Mycobacterium smegmatis genome. Gene expression changes were mapped onto the metabolic network using Active Modules for Bipartite Networks (AMBIENT) to identify metabolic pathways showing coordinated transcriptional responses to the stress. AMBIENT revealed several key features of the metabolic response not identified by KEGG enrichment alone. Down regulated reactions were associated with the general reduction in cellular metabolism as a consequence of reduced growth rate. Up-regulated modules highlighted metabolic changes in nitrogen assimilation and scavenging, as well as reactions involved in hydrogen peroxide metabolism, carbon scavenging and energy generation.

Conclusions

Application of an Active Modules algorithm to transcriptomic data identified key metabolic reactions and pathways altered in response to nitrogen stress, which are central to survival under nitrogen limiting environments.
Mesocortical dopamine system modulates mechanical nociceptive responses recorded in the rat prefrontal cortex
Authors: Sogabe Shoichi , Yagasaki Yuki , Onozawa Kitaro , Kawakami Yoriko
Published: July 2013

Background

Psychological conditions affect pain responses in the human anterior cingulate cortex (ACC) according to brain imaging analysis. The rodent prefrontal cortex (PFC) including cingulate areas is also related to the affective dimension of pain. We previously reported PFC nociceptive responses inhibited by inputs from the amygdala, such as with dopamine (DA) D2receptor (D2R) blockers, to show decreased effect on amygdala projections. In this study, we examined whether direct projections from the ventral tegmental area (VTA) to the PFC affect nociceptive responses in the PFC.

Results

High frequency stimulation (HFS, 50 Hz, 30 s) delivered to the VTA produced long-lasting suppression (LLS) of nociceptive responses in the rat PFC including cingulate and prelimbic areas. Nociceptive responses evoked by mechanical pressure stimulation (2 s duration at 500 g constant force) applied to the tails of urethane-anesthetized rats were recorded using extracellular unit recording methods in the PFC. HFS delivered to the VTA, which has been reported to increase DA concentrations in the PFC, significantly suppressed nociceptive responses. The LLS of nociceptive responses persisted for about 30 minutes and recovered to the control level within 60 min after HFS. We also demonstrated local microinjection of a selective D2agonist of DA receptors to induce LLS of mechanical nociceptive responses, while a D2but not a D1antagonist impaired the LLS evoked by HFS. In contrast, DA depletion by a 6-hydroxydopamine injection or a low concentration of DA induced by a κ-opiate receptor agonist injected into the VTA had minimal effect on nociceptive responses in the PFC.

Conclusion

HFS delivered to VTA inhibited nociceptive responses for a long period in PFC. DA D2R activation mediated by local D2agonist injection also induced LLS of mechanical nociceptive responses. The mesocortical DA system may modify PFC nociceptive responses via D2activity.
Oral supplementation with areca-derived polyphenols attenuates food allergic responses in ovalbumin-sensitized mice
Authors: Wang Chia-Chi , Lin Yu-Ru , Liao Mei-Hsiu , Jan Tong-Rong
Published: July 2013

Background

Arecae semen, the dried slice of areca nuts, is a traditional Chinese medicine used to treat intestinal parasitosis, rectal tenesmus and diarrhea. Areca nuts contain a rich amount of polyphenols that have been shown to modulate the functionality of mast cells and T cells. The objective of this study is to investigate the effect of polyphenol-enriched areca nut extracts (PANE) against food allergy, a T cell-mediated immune disorder.

Methods

BALB/c mice were left untreated or administered with PANE (0.05% and 0.1%) via drinking water throughout the entire experiment. The mice were sensitized with ovalbumin (OVA) twice by intraperitoneal injection, and then repeatedly challenged with OVA by gavage to induce food allergic responses.

Results

PANE administration attenuated OVA-induced allergic responses, including the occurrence of diarrhea and the infiltration and degranulation of mast cells in the duodenum. The serum level of OVA-specific IgE and the expression of interleukin-4 in the duodenum were suppressed by PANE treatment. In addition, PANE administration induced Gr-1+, IL-10+ and Gr-1+IL-10+ cells in the duodenum.

Conclusion

These results demonstrate that oral intake of areca-derived polyphenols attenuates food allergic responses accompanied with a decreased Th2 immunity and an enhanced induction of functional myeloid-derived suppressor cells.
Hetero- and adaptive resistance to polymyxin B in OXA-23-producing carbapenem-resistant Acinetobacter baumannii isolates
Authors: Barin Juliana , Martins Andreza Francisco , Heineck Bianca Lucia , Barth Afonso Luis , Zavascki Alexandre Prehn
Published: July 2013

Background

Resistance rates to polymyxin B in surveillance studies have been very low despite its increasing use worldwide as the last resort therapy for multidrug-resistant Gram-negative bacilli. However, two other resistance phenotypes, hetero- and adaptive resistance, have been reported to polymyxin. We aimed to investigate the presence of polymyxin B hetero- and adaptive resistance and evaluate its stability in carbapenem-resistant Acinetobacter baumannii (CRAB) clinical isolates.

Methods

CRAB isolates were recovered from hospitalized patients at three Brazilian hospitals. Hetero-resistance was determined by population analysis profile (PAP). Adaptive resistance was evaluated after serial daily passages of isolates in Luria-Bertani broth containing increasing polymyxin B concentrations. MICs of polymyxin B of colonies growing at the highest polymyxin B concentration were further determined after daily sub-cultured in antibiotic-free medium and after storage at −80°C, in some selected isolates.

Results

Eighty OXA-23-producing CRAB isolates were typed resulting in 15 distinct clones. Twenty-nine randomly selected isolates (at least one from each clone) were selected for hetero- resistance evaluation: 26 (90%) presented growth of subpopulations with higher polymyxin B MIC than the original one in PAP. No isolate has grown at polymyxin B concentrations higher than 2 mg/L. Polymyxin B MICs of subpopulations remained higher than the original population after daily passages on antibiotic-free medium but returned to the same or similar levels after storage. Twenty-two of the 29 isolates (at least one from each clone) were evaluated for adaptive resistance: 12 (55%) presented growth in plates containing 64 mg/L of polymyxin B. Polymyxin B MICs decreased after daily passages on antibiotic-free medium and returned to the same levels after storage.

Conclusions

The presence of subpopulations with higher polymyxin B MIC was extremely common and high-level adaptive resistance was very frequent in CRAB isolates.
Fat utilization and arterial hypertension in overweight/obese subjects
Authors: Ferro Yvelise , Gazzaruso Carmine , Coppola Adriana , Romeo Stefano , Migliaccio Valeria , Giustina Andrea , Pujia Arturo , Montalcini Tiziana
Published: July 2013

Background

The Respiratory Quotient is a parameter reflecting the utilization of the nutrients by a subject. It is associated with an high rate of subsequent weight gain and with the atherosclerosis. Subjects tending to burn less fat have an increased Respiratory Quotient. Aim of this study was to investigate on the relationship between the Respiratory Quotient and the cardiovascular risk factors.

Methods

In this cross-sectional study we enrolled 223 individuals of both sexes aged 45–75 ys that were weight stable, receiving a balanced diet, and not affected by debilitating disease or cardiovascular disease. The Respiratory Quotient was measured by Indirect Calorimetry. The measurement of the Blood Pressure was obtained by a mercury sphygmomanometer.

Results

We enrolled 133 female and 90 male. Systolic blood pressure only was positively correlated to the Respiratory Quotient in univariate and multivariate regression analysis (p=0,017). The prevalence of hypertension was significatively different between the quartiles of the Respiratory Quotient, with the highest prevalence in the IV quartile (p=0,024).

Conclusion

High value of the Respiratory Quotient, an index of nutrients utilization, is associated to an high prevalence of Hypertension. It is possible that in the subjects with high Respiratory Quotient and high body mass index, the activation of the renin angiotensin system, in concert to the reduction of the utilization of the endogenous fat stores, could increase the risk of hypertension.
Vascular leak ensues a vigorous proinflammatory cytokine response to Tacaribe arenavirus infection in AG129 mice
Authors: Sefing Eric J , Wong Min-Hui , Larson Deanna P , Hurst Brett L , Van Wettere Arnaud J , Schneller Stewart W , Gowen Brian B
Published: July 2013

Background

Tacaribe virus (TCRV) is a less biohazardous relative of the highly pathogenic clade B New World arenaviruses that cause viral hemorrhagic fever syndromes and require handling in maximum containment facilities not readily available to most researchers. AG129 type I and II interferon receptor knockout mice have been shown to be susceptible to TCRV infection, but the pathogenic mechanisms contributing to the lethal disease are unclear.

Methods

To gain insights into the pathogenesis of TCRV infection in AG129 mice, we assessed hematologic and cytokine responses during the course of infection, as well as changes in the permeability of the vascular endothelium. We also treated TCRV-challenged mice with MY-24, a compound that prevents mortality without affecting viral loads during the acute infection, and measured serum and tissue viral titers out to 40 days post-infection to determine whether the virus is ultimately cleared in recovering mice.

Results

We found that the development of viremia and splenomegaly precedes an elevation in white blood cells and the detection of high levels of proinflammatory mediators known to destabilize the endothelial barrier, which likely contributes to the increased vascular permeability and weight loss that was observed several days prior to when the mice generally succumb to TCRV challenge. In surviving mice treated with MY-24, viremia and liver virus titers were not cleared until 2–3 weeks post-infection, after which the mice began to recover lost weight. Remarkably, substantial viral loads were still present in the lung, spleen, brain and kidney tissues at the conclusion of the study.

Conclusions

Our findings suggest that vascular leak may be a contributing factor in the demise of TCRV-infected mice, as histopathologic findings are generally mild to moderate in nature, and as evidenced with MY-24 treatment, animals can survive in the face of high viral loads.
RApid Primary care Initiation of Drug treatment for Transient Ischaemic Attack (RAPID−TIA): study protocol for a pilot randomised controlled trial
Authors: Edwards Duncan , Fletcher Kate , Deller Rachel , McManus Richard , Lasserson Daniel , Giles Matthew , Sims Don , Norrie John , McGuire Graham , Cohn Simon , Whittle Fiona , Hobbs Vikki , Weir Christopher , Mant Jonathan
Published: July 2013

Background

People who have a transient ischaemic attack (TIA) or minor stroke are at high risk of a recurrent stroke, particularly in the first week after the event. Early initiation of secondary prevention drugs is associated with an 80% reduction in risk of stroke recurrence. This raises the question as to whether these drugs should be given before being seen by a specialist – that is, in primary care or in the emergency department. The aims of the RAPID-TIA pilot trial are to determine the feasibility of a randomised controlled trial, to analyse cost effectiveness and to ask: Should general practitioners and emergency doctors (primary care physicians) initiate secondary preventative measures in addition to aspirin in people they see with suspected TIA or minor stroke at the time of referral to a specialist?

Methods/Design

This is a pilot randomised controlled trial with a sub-study of accuracy of primary care physician diagnosis of TIA. In the pilot trial, we aim to recruit 100 patients from 30 general practices (including out-of-hours general practice centres) and 1 emergency department whom the primary care physician diagnoses with TIA or minor stroke and randomly assign them to usual care (that is, initiation of aspirin and referral to a TIA clinic) or usual care plus additional early initiation of secondary prevention drugs (a blood-pressure lowering protocol, simvastatin 40 mg and dipyridamole 200 mg m/r bd). The primary outcome of the main study will be the number of strokes at 90 days. The diagnostic accuracy sub-study will include these 100 patients and an additional 70 patients in whom the primary care physician thinks the diagnosis of TIA is possible, rather than probable. For the pilot trial, we will report recruitment rate, follow-up rate, a preliminary estimate of the primary event rate and occurrence of any adverse events. For the diagnostic study, we will calculate sensitivity and specificity of primary care physician diagnosis using the final TIA clinic diagnosis as the reference standard.

Discussion

This pilot study will be used to estimate key parameters that are needed to design the main study and to estimate the accuracy of primary care diagnosis of TIA. The planned follow-on trial will have important implications for the initial management of people with suspected TIA.

Trial registration

ISRCTN62019087
The role of traditional medicine practice in primary health care within Aboriginal Australia: a review of the literature
Authors: Oliver Stefanie J
Published: July 2013

The practice of traditional Aboriginal medicine within Australia is at risk of being lost due to the impact of colonisation. Displacement of people from traditional lands as well as changes in family structures affecting passing on of cultural knowledge are two major examples of this impact. Prior to colonisation traditional forms of healing, such as the use of traditional healers, healing songs and bush medicines were the only source of primary health care. It is unclear to what extent traditional medical practice remains in Australia in 2013 within the primary health care setting, and how this practice sits alongside the current biomedical health care model. An extensive literature search was performed from a wide range of literature sources in attempt to identify and examine both qualitatively and quantitatively traditional medicine practices within Aboriginal Australia today. Whilst there is a lack of academic literature and research on this subject the literature found suggests that traditional medicine practice in Aboriginal Australia still remains and the extent to which it is practiced varies widely amongst communities across Australia. This variation was found to depend on association with culture and beliefs about disease causation, type of illness presenting, success of biomedical treatment, and accessibility to traditional healers and bush medicines. Traditional medicine practices were found to be used sequentially, compartmentally and concurrently with biomedical healthcare. Understanding more clearly the role of traditional medicine practice, as well as looking to improve and support integrative and governance models for traditional medicine practice, could have a positive impact on primary health care outcomes for Aboriginal Australia.
Evolution and homoplasy at the Bem6 microsatellite locus in three sweetpotato whitefly (Bemisia tabaci) cryptic species
Authors: Dickey Aaron M , Hall Paula M , Shatters Robert G , Mckenzie Cindy L
Published: July 2013

Background

The evolution of individual microsatellite loci is often complex and homoplasy is common but often goes undetected. Sequencing alleles at a microsatellite locus can provide a more complete picture of the common evolutionary mechanisms occurring at that locus and can reveal cases of homoplasy. Within species homoplasy can lead to an underestimate of differentiation among populations and among species homoplasy can produce a misleading interpretation regarding shared alleles and hybridization. This is especially problematic with cryptic species.

Results

By sequencing alleles from three cryptic species of the sweetpotato whitefly (Bemisia tabaci), designated MEAM1, MED, and NW, the evolution of the putatively dinucleotide Bem6 (CA8)imp microsatellite locus is inferred as one of primarily stepwise mutation occurring at four distinct heptaucleotide tandem repeats. In two of the species this pattern yields a compound tandem repeat. Homoplasy was detected both among species and within species.

Conclusions

In the absence of sequencing, size homoplasious alleles at the Bem6 locus lead to an overestimate of alleles shared and hybridization among cryptic species of Bemisia tabaci. Furthermore, the compound heptanucleotide motif structure of a putative dinucleotide microsatellite has implications for the nomenclature of heptanucleotide tandem repeats with step-wise evolution.