bluuebunny/crossref_metadata_2025 huggingface dataset:
Staphylococcus epidermidis Esp Degrades Specific Proteins Associated with Staphylococcus aureus Biofilm Formation and Host-Pathogen Interaction
Authors: Sugimoto Shinya , Iwamoto Takeo , Takada Koji , Okuda Ken-ichi , Tajima Akiko , Iwase Tadayuki , Mizunoe Yoshimitsu
Published: January 2013

Staphylococcus aureus
exhibits a strong capacity to attach to abiotic or biotic surfaces and form biofilms, which lead to chronic infections. We have recently shown that Esp, a serine protease secreted by commensal
Staphylococcus epidermidis
, disassembles preformed biofilms of
S. aureus
and inhibits its colonization. Esp was expected to degrade protein determinants of the adhesive and cohesive strength of
S. aureus
biofilms. The aim of this study was to elucidate the substrate specificity and target proteins of Esp and thereby determine the mechanism by which Esp disassembles
S. aureus
biofilms. We used a mutant Esp protein (Esp
S235A
) with defective proteolytic activity; this protein did not disassemble the biofilm formed by a clinically isolated methicillin-resistant
S. aureus
(MRSA) strain, thereby indicating that the proteolytic activity of Esp is essential for biofilm disassembly. Esp degraded specific proteins in the biofilm matrix and cell wall fractions, in contrast to proteinase K, which is frequently used for testing biofilm robustness and showed no preference for proteolysis. Proteomic and immunological analyses showed that Esp degrades at least 75 proteins, including 11 biofilm formation- and colonization-associated proteins, such as the extracellular adherence protein, the extracellular matrix protein-binding protein, fibronectin-binding protein A, and protein A. In addition, Esp selectively degraded several human receptor proteins of
S. aureus
(e.g., fibronectin, fibrinogen, and vitronectin) that are involved in its colonization or infection. These results suggest that Esp inhibits
S. aureus
colonization and biofilm formation by degrading specific proteins that are crucial for biofilm construction and host-pathogen interaction.
Acupuncture in Australian General Practice: Trends in Reimbursed Acupuncture Services from 1995 to 2011
Authors: Wardle Jonathan Lee , Adams Jon , Sibbritt David William
Published: January 2013

Objectives

To ascertain the extent of and trends in the use of acupuncture in Australian general practice and the characteristics of patients receiving publicly subsidised acupuncture services from general practitioners (GPs).

Design

Secondary analysis of national patient Medicare data for claims by all non-specialist medical practitioners for Medicare Benefits Schedule items for an attendance where acupuncture was performed by a medical practitioner from 1995 to 2011.

Main Outcome Measures

Use of acupuncture by GPs, patients’ sex and age and the socioeconomic disadvantage index of GP's practice.

Results

There has been a 47.7% decline in the number of acupuncture claims by GPs per 100 000 population in the period from 1995 to 2011. Acupuncture claims were made by 3.4% of GPs in 2011. Women were almost twice as likely to receive acupuncture from a GP as men, and patients in urban areas were more than twice as likely to receive acupuncture from a GP as patients in rural areas. Acupuncture claims were highest in areas that were socioeconomically advantaged.

Conclusions

Claims for reimbursement for acupuncture by GPs have declined significantly in Australian general practice even though the use of acupuncture by the Australian public has increased. This may be due to increased use of referrals or use of non-medical practitioners, barriers to acupuncture practice in general practice or non-specific factors affecting reimbursement for non-vocationally registered GPs.
Electroacupuncture Alleviates Intraoperative Immunosuppression in Patients Undergoing Supratentorial Craniotomy
Authors: Li Guoyan , Li Shuqin , An Lixin , Wang Baoguo
Published: January 2013

Background

Clinical experience suggests that anaesthesia using a combination of acupuncture and drugs can reduce the dosage of anaesthetics required for craniotomy, decreasing both the disturbance in physiological functions during the operation and postoperative complications and improving the rate of recovery. The aim of the present study was to investigate the impact of electroacupuncture (EA) on the dynamic equilibrium of the immune system and immune cell populations during the pericraniotomy period.

Methods

A total of 56 patients undergoing craniotomy were randomised into three groups: control (C, n=18), EA (A, n=19) and sham acupuncture (S, n=19) groups. Blood samples were collected before anaesthesia (T0) and 30 min, 2 h and 4 h after induction of anaesthesia (T1, T2 and T3, respectively,) to measure the levels of tumour necrosis factor α (TNFα), interleukin (IL)-8, IL-10, IgM, IgA, IgG and full blood count.

Results

There was no significant difference between the measurements in groups A and S during craniotomy. The levels of IgM and IgA decreased significantly in group C compared with groups A and S at T2 and T3 time points. The levels of total T cells and suppressor T cells in group C decreased significantly compared with groups A and S at T1 and T2, and the level of natural killer cells in group C decreased significantly compared with groups A and S at T1. No significant differences between groups were found in the levels of TNFα, IgG, IL-10, IL-8, leucocytes, neutrophils, monocytes, Th cells or B cells.

Conclusions

EA appears to reduce immunosuppression of both the humoral and cellular components during surgery.
The evaluation of speed skating helmet performance through peak linear and rotational accelerations
Authors: Karton Clara , Rousseau Philippe , Vassilyadi Michael , Hoshizaki Thomas Blaine
Published: January 2013

Objective

Like many sports involving high speeds and body contact, head injuries are a concern for short track speed skating athletes and coaches. While the mandatory use of helmets has managed to nearly eliminate catastrophic head injuries such as skull fractures and cerebral haemorrhages, they may not be as effective at reducing the risk of a concussion. The purpose of this study was to evaluate the performance characteristics of speed skating helmets with respect to managing peak linear and peak rotational acceleration, and to compare their performance against other types of helmets commonly worn within the speed skating sport.

Materials and methods

Commercially available speed skating, bicycle and ice hockey helmets were evaluated using a three-impact condition test protocol at an impact velocity of 4 m/s.

Results and discussion

Two speed skating helmet models yielded mean peak linear accelerations at a low-estimated probability range for sustaining a concussion for all three impact conditions. Conversely, the resulting mean peak rotational acceleration values were all found close to the high end of a probability range for sustaining a concussion. A similar tendency was observed for the bicycle and ice hockey helmets under the same impact conditions.

Conclusion

Speed skating helmets may not be as effective at managing rotational acceleration and therefore may not successfully protect the user against risks associated with concussion injuries.
Running in a minimalist and lightweight shoe is not the same as running barefoot: a biomechanical study
Authors: Bonacci Jason , Saunders Philo U , Hicks Amy , Rantalainen Timo , Vicenzino Bill (Guglielmo) T , Spratford Wayne
Published: January 2013

Aim

The purpose of this study was to determine the changes in running mechanics that occur when highly trained runners run barefoot and in a minimalist shoe, and specifically if running in a minimalist shoe replicates barefoot running.

Methods

Ground reaction force data and kinematics were collected from 22 highly trained runners during overground running while barefoot and in three shod conditions (minimalist shoe, racing flat and the athlete's regular shoe). Three-dimensional net joint moments and subsequent net powers and work were computed using Newton-Euler inverse dynamics. Joint kinematic and kinetic variables were statistically compared between barefoot and shod conditions using a multivariate analysis of variance for repeated measures and standardised mean differences calculated.

Results

There were significant differences between barefoot and shod conditions for kinematic and kinetic variables at the knee and ankle, with no differences between shod conditions. Barefoot running demonstrated less knee flexion during midstance, an 11% decrease in the peak internal knee extension and abduction moments and a 24% decrease in negative work done at the knee compared with shod conditions. The ankle demonstrated less dorsiflexion at initial contact, a 14% increase in peak power generation and a 19% increase in the positive work done during barefoot running compared with shod conditions.

Conclusions

Barefoot running was different to all shod conditions. Barefoot running changes the amount of work done at the knee and ankle joints and this may have therapeutic and performance implications for runners.
Video analysis of situations with a high-risk for injury in Norwegian male professional football; a comparison between 2000 and 2010
Authors: Bjørneboe John , Bahr Roald , Einar Andersen Thor
Published: January 2013

Background

A recent study from Norwegian male professional football found that the risk of acute match injuries increased from 2002 to 2007.

Objective

To compare the incidence of incidents with a propensity for injury, from the 2000 season to the 2010 season in Norwegian male professional football using video analysis.

Methods

We conducted a video analysis of incidents in Norwegian professional football. An incident was recorded if the match was interrupted by the referee, and the player lay down for more than 15 s, and appeared to be in pain or received medical treatment. We also conducted a video analysis of all player-to-player contact situations occurring during 30 randomly selected matches.

Results

A total of 1287 incidents were identified during the two seasons. The corresponding rate of incidents was 74.4 (95% CI 67.3 to 81.5) in the 2000 season and 109.6 (95% CI 102.3 to 116.9) in the 2010 season, a significant increase from 2000 to 2010 (rate ratio 1.47, 95% CI 1.31 to 1.66). We observed a significantly higher rate of opponent-to-player contact and non-contact incidents in the 2010 season, but no change in the proportion of fouls or sanctions awarded by the referee. The rate of player-to-player contact situations in both heading and tackling duels was lower during the 2010 season.

Conclusions

We found an increased rate of non-contact and opponent-to-player contact incidents in both heading and tackling duels in the 2010 season compared with 10 years earlier, even if there was no increase in the frequency of player-to-player contact situations.
Major limitations in knowledge of physical activity guidelines among UK medical students revealed: implications for the undergraduate medical curriculum
Authors: Dunlop Michael , Murray Andrew Duncan
Published: January 2013

Background

Education of health professionals is a key element of the wider strategy to increase society's physical activity levels. To date, no study has directly assessed UK medical students’ knowledge of physical activity guidelines or their ability/willingness to prescribe exercise.

Methods

A questionnaire survey of final year medical students in Scottish Universities was conducted prior to a presentation on the current UK guidelines.

Results

Completed questionnaires (n=177) represented 37% of the final year cohorts. Physical inactivity was incorrectly perceived to be the least important risk factor to global mortality. 40% stated they were aware of current guidelines, but in a forced choice, 68% were able to correctly identify them for adults. In comparison, 97% correctly identified the UK's alcohol guidelines. 52% stated they felt adequately trained to give physical activity advice to the general public.

Conclusions

The medical students in this study underestimated the risk of physical inactivity, and did not know the physical activity guidelines as well as other health promotion guidelines. A large proportion remained unconfident about giving physical activity advice. Improved education of this group is required.
Assessment of whole body MRI and sestamibi technetium-99m bone marrow scan in prediction of multiple myeloma disease progression and outcome: a prospective comparative study
Authors: Khalafallah Alhossain A , Snarski Andrew , Heng Robert , Hughes Ryan , Renu Shamsunnaher , Arm Jameen , Dutchke Richard , Robertson Iain K , To Luen B
Published: January 2013

Objectives

This study aims primarily to determine whether whole body MRI (WB-MRI) and Sestamibi Technetium-99m-bone marrow (MIBI) scans in the same patients produce the same estimate of disease load and location, and secondly, to study possible association between the bone disease detected by these scans and the effect on disease outcome and survival. Bone disease occurs in about 90% of multiple myeloma (MM) patients. There are no data comparing the new diagnostic modalities with WB-MRI and MIBI in MM.

Design

A prospective comparative study between WB-MRI and MIBI scans in assessing bone disease and outcome of MM.

Participants and methods

Sixty-two consecutive patients with confirmed MM underwent simultaneous WB-MRI (both axial T1 and turbo spin echo short tau inversion recovery (STIR)) and MIBI scans at a single institution from January 2010 to January 2011, and their survival status was determined in January 2012. The median age was 62 years (range 37–88) with a male-to-female ratio of 33 : 29.

Results

In vertebrae and long bones, MRI scan detected more disease compared with MIBI scan (p<0.001) but there was less difference in the skull (p=0.09). In the ribcage, the MIBI scan detected more lytic lesions of the ribs compared with MRI scan (p<0.001). Thirteen of the 62 patients died during the 24-month follow-up. Increased disease detected in all bones by both scans was associated with increased mortality risk (MIBI p=0.001; MRI-STIR p=0.044; but not MRI-T1 p=0.44). In all combined bone groups, the mean MIBI scan results provided a better prediction of mortality than MRI scan over the follow-up period (MRI-T1 vs MIBI p=0.019; MRI-STIR vs MIBI p=0.047).

Conclusions

Although WB-MRI detected more MM bone disease, MIBI scan predicted overall disease outcome and mortality better than MRI scan. Further studies to define optimum use of these imaging techniques are warranted.

Trial registration number

The study was registered prospectively in the Australian and New Zealand Clinical Trials Registry athttp://www.ANZCTR.org.auunder No: ACTRN12609000761268.
Analysis of venous drainage in three patients with extradural spinal arteriovenous fistulae at the craniovertebral junction with potentially benign implication
Authors: Puri Ajit S , Telischak Nicholas Alexander , Vissapragada Ravi , Thomas Ajith J
Published: January 2013

Background

Extradural arteriovenous fistulae (AVFs) are vascular malformations that result from a direct connection between an extradural artery and vein, resulting in a high flow fistula that drains into the epidural venous system. Extradural AVFs may cause myelopathy when distended epidural veins compress the cord or when venous hypertension causes venous stasis within the spinal cord, and are uncommon causes of subarachnoid hemorrhage (SAH), although the presence of intracranial drainage is a risk factor for SAH. There are numerous reports of SAH and AVF with rostral intracranial venous drainage, implying an intradural drainage pathway. To our knowledge, a cervical spinal AVF at the craniovertebral junction (occurring between the occiput and C2) with exclusively extradural drainage and without a significant epidural component has not been described previously.

Methods

A retrospective review was performed identifying three patients treated at our hospital with cervical spinal AVF and extradural venous drainage.

Results

We present three cases of cervical spinal AVF with exclusive extradural venous drainage without accompanying intradural drainage—cranial or spinal. All three patients with exclusively extradural drainage have done well after 24 months of follow-up. The anatomical, clinical, and radiologic features are presented.

Conclusions

Patients with cervical AVF and exclusively extradural drainage pathways form a separate entity, representing a subset with a less ominous natural history.
Geographical and temporal variation of injection drug users in Pakistan
Authors: Archibald Chris P , Shaw Souradet Y , Emmanuel Faran , Otho Suleman , Reza Tahira , Altaf Arshad , Musa Nighat , Thompson Laura H , Blanchard James F
Published: January 2013

Objectives

We describe the characteristics of injecting drug users (IDU) in Pakistan in 2006 and 2011, and assess the heterogeneity of IDU characteristics across different cities and years as well as factors associated with HIV infection.

Methods

Cross-sectional, integrated behavioural-biological surveys of IDU were conducted in 10 cities across Pakistan in 2006 and 2011. Univariate and multivariable analyses were used to describe the differences in HIV prevalence and risk behaviours between cities and over time.

Results

Large increases in HIV prevalence among injection drug users in Pakistan were observed, with overall HIV prevalence increasing from 16.2% in 2006 to 31.0% in 2011; an increase in HIV prevalence was also seen in all geographic areas except one. There was an increase in risk behaviours between 2006 and 2011, anecdotally related to a reduction in the availability of services for IDU. In 2011, larger proportions of IDU reported injecting several times a day and using professional injectors, and fewer reported always using clean syringes. An increase in the proportion living on the street was also observed and this was associated with HIV infection. Cities differ in terms of HIV prevalence, risk profiles, and healthcare seeking behaviours.

Conclusions

There is a high prevalence of HIV among injection drug users in Pakistan and considerable potential for further transmission through risk behaviours. HIV prevention programs may be improved through geographic targeting of services within a city and for involving groups that interact with IDU (such as pharmacy staff and professional injectors) in harm reduction initiatives.
Placental growth factor increases regional myocardial blood flow and contractile function in chronic myocardial ischemia
Authors: Liu Xiaoshun , Claus Piet , Wu Ming , Reyns Geert , Verhamme Peter , Pokreisz Peter , Vandenwijngaert Sara , Dubois Christophe , Vanhaecke Johan , Verbeken Erik , Bogaert Jan , Janssens Stefan
Published: January 2013

Placental growth factor (PlGF) has a distinct biological phenotype with a predominant proangiogenic role in disease without affecting quiescent vessels in healthy organs. We tested whether systemic administration of recombinant human (rh)PlGF improves regional myocardial blood flow (MBF) and systolic function recovery in a porcine chronic myocardial ischemia model. We implanted a flow-limiting stent in the proximal left anterior descending coronary artery and measured systemic hemodynamics, regional myocardial function using MRI, and blood flow using colored microspheres 4 wk later. Animals were then randomized in a blinded way to receive an infusion of rhPlGF (15 μg·kg−1·day−1, n = 9) or PBS (control; n = 10) for 2 wk. At 8 wk, myocardial perfusion and function were reassessed. Infusion of rhPlGF transiently increased PlGF serum levels >30-fold (1,153 ± 180 vs. 33 ± 18 pg/ml at baseline, P < 0.001) without affecting systemic hemodynamics. From 4 to 8 wk, rhPlGF increased regional MBF from 0.46 ± 0.11 to 0.85 ± 0.16 ml·min−1·g−1, with a concomitant increase in systolic wall thickening from 11 ± 3% to 26 ± 5% in the ischemic area. In control animals, no significant changes from 4 to 8 wk were observed (MBF: 0.45 ± 0.07 to 0.49 ± 0.08 ml·min−1·g−1 and systolic wall thickening: 14 ± 4% to 18 ± 1%). rhPlGF-induced functional improvement was accompanied by increased myocardial neovascularization, enhanced glycogen utilization, and reduced oxidative stress and cardiomyocyte apoptosis in the ischemic zone. In conclusion, systemic rhPlGF infusion significantly enhances regional blood flow and contractile function of the chronic ischemic myocardium without adverse effects. PlGF protein infusion may represent an attractive therapeutic strategy to increase myocardial perfusion and energetics in chronic ischemic cardiomyopathy.
Heart rate changes mediate the embryotoxic effect of antiarrhythmic drugs in the chick embryo
Authors: Kockova Radka , Svatunkova Jarmila , Novotny Jiri , Hejnova Lucie , Ostadal Bohuslav , Sedmera David
Published: January 2013

A significant increase in cardiovascular medication use during pregnancy occurred in recent years. Only limited evidence on safety profiles is available, and little is known about the mechanisms of adverse effect on the fetus. We hypothesized that drug-induced bradycardia is the leading mechanism of developmental toxicity. Embryotoxicity was tested in ovo after administration of various doses of metoprolol, carvedilol, or ivabradine. Embryonic day (ED) 4 and 8 chick embryos were studied by video microscopy and ultrasound biomicroscopy ex ovo after intraamniotic injection of the drug for a period of 30 min. Stroke volume was calculated by the Simpson method and prolate ellipsoid formula. Significant dose-dependent mortality was achieved in embryos injected with carvedilol and ivabradine. In ED4 embryos, metoprolol, carvedilol, and ivabradine reduced the heart rate by 33%, 27%, and 55%, respectively, compared with controls (6%). In ED8 embryos this effect was more pronounced with a heart rate reduction by 71%, 54%, and 53%, respectively (controls, 36%). Cardiac output decreased in all tested groups but only proved significant in the metoprolol group in ED8 embryos. The number of β-adrenergic receptors showed a downward tendency during embryonic development. A negative chronotropic effect of metoprolol, carvedilol, and ivabradine was increasingly pronounced with embryonic maturity despite a downward trend in the number of β-adrenergic receptors. This effect was associated with reduced cardiac output in chick embryos, probably leading to premature death. Although standard doses of these drugs appear relatively safe, high doses have a potentially adverse effect on the fetus through reduced heart rate.
Impaired acetylcholine-induced cutaneous vasodilation in young smokers: roles of nitric oxide and prostanoids
Authors: Fujii Naoto , Reinke Maggie C. , Brunt Vienna E. , Minson Christopher T.
Published: January 2013

Cigarette smoking attenuates acetylcholine (ACh)-induced cutaneous vasodilation in humans, but the underlying mechanisms are unknown. We tested the hypothesis that smokers have impaired nitric oxide (NO)- and cyclooxygenase (COX)-dependent cutaneous vasodilation to ACh infusion. Twelve young smokers, who have smoked more than 5.2 ± 0.7 yr with an average daily consumption of 11.4 ± 1.2 cigarettes, and 12 nonsmokers were tested. Age, body mass index, and resting mean arterial pressure were similar between the groups. Cutaneous vascular conductance (CVC) was evaluated as laser-Doppler flux divided by mean arterial pressure, normalized to maximal CVC (local heating to 43.0°C plus sodium nitroprusside administration). We evaluated the increase in CVC from baseline to peak (CVCΔpeak) and area under the curve of CVC (CVCAUC) during a bolus infusion (1 min) of 137.5 μM ACh at four intradermal microdialysis sites: 1) Ringer (control), 2) 10 mM NG-nitro-l-arginine methyl ester (l-NAME; NO synthase inhibitor), 3) 10 mM ketorolac (COX inhibitor), and 4) combination of l-NAME + ketorolac. CVCΔpeakand CVCAUCat the Ringer site in nonsmokers were greater than in smokers (CVCΔpeak, 42.9 ± 5.1 vs. 22.3 ± 3.5%max, P < 0.05; and CVCAUC, 8,085 ± 1,055 vs. 3,145 ± 539%max·s, P < 0.05). In nonsmokers, CVCΔpeakand CVCAUCat the l-NAME site were lower than the Ringer site (CVCΔpeak, 29.5 ± 6.2%max, P < 0.05; and CVCAUC, 5,377 ± 1,109%max·s, P < 0.05), but in smokers, there were no differences between the Ringer and l-NAME sites (CVCΔpeak, 16.8 ± 4.3%max, P = 0.11; and CVCAUC, 2,679 ± 785%max·s, P = 0.30). CVCΔpeakand CVCAUCwere reduced with ketorolac in nonsmokers (CVCΔpeak, 13.3 ± 3.6%max, P < 0.05; and CVCAUC, 1,967 ± 527%max·s, P < 0.05) and smokers (CVCΔpeak, 7.8 ± 1.8%max, P < 0.05; and CVCAUC, 1,246 ± 305%max·s, P < 0.05) and at the combination site in nonsmokers (CVCΔpeak, 15.9 ± 3.1%max, P < 0.05; and CVCAUC, 2,660 ± 512%max·s, P < 0.05) and smokers (CVCΔpeak, 11.5 ± 2.6%max, P < 0.05; and CVCAUC, 1,693 ± 409%max·s, P < 0.05), but the magnitudes were greater in nonsmokers ( P < 0.05). These results suggest that impaired ACh-induced skin vasodilation in young smokers is related to diminished NO- and COX-dependent vasodilation.
Oxidative activation of Ca2+/calmodulin-activated kinase II mediates ER stress-induced cardiac dysfunction and apoptosis
Authors: Roe Nathan D. , Ren Jun
Published: January 2013

Endoplasmic reticulum (ER) stress elicits oxidative stress and intracellular Ca2+ derangement via activation of Ca2+/calmodulin-dependent protein kinase II (CaMKII). This study was designed to examine the role of CaMKII in ER stress-induced cardiac dysfunction and apoptosis as well as the effect of antioxidant catalase. Wild-type FVB and transgenic mice with cardiac-specific overexpression of catalase were challenged with the ER stress inducer tunicamycin (3 mg/kg ip for 48 h). Presence of ER stress was verified using the ER stress protein markers immunoglobulin binding protein (BiP) and C/EBP homologous protein (CHOP), the effect of which was unaffected by catalase overexpression. Echocardiographic assessment revealed that tunicamycin elicited cardiac remodeling (enlarged end-systolic diameter without affecting diastolic and ventricular wall thickness), depressed fractional shortening, ejection fraction, and cardiomyocyte contractile capacity, intracellular Ca2+ mishandling, accumulation of reactive oxygen species (superoxide production and NADPH oxidase p47phox level), CaMKII oxidation, and apoptosis (evidenced by Bax, Bcl-2/Bax ratio, and TUNEL staining), the effects of which were obliterated by catalase. Interestingly, tunicamycin-induced cardiomyocyte mechanical anomalies and cell death were ablated by the CaMKII inhibitor KN93, in a manner reminiscent of catalase. These data favored a permissive role of oxidative stress and CaMKII activation in ER stress-induced cardiac dysfunction and cell death. Our data further revealed the therapeutic potential of antioxidant or CaMKII inhibition in cardiac pathological conditions associated with ER stress. This research shows for the first time that contractile dysfunction caused by ER stress is a result of the oxidative activation of the CaMKII pathway.
Increased expression of senescence markers in cystic fibrosis airways
Authors: Fischer Bernard M. , Wong Jessica K. , Degan Simone , Kummarapurugu Apparao B. , Zheng Shuo , Haridass Prashamsha , Voynow Judith A.
Published: January 2013

Cystic Fibrosis (CF) is a chronic lung disease characterized by chronic neutrophilic airway inflammation and increased levels of neutrophil elastase (NE) in the airways. We have previously reported that NE treatment triggers cell cycle arrest. Cell cycle arrest can lead to senescence, a complete loss of replicative capacity. Importantly, senescent cells can be proinflammatory and would perpetuate CF chronic inflammation. By immunohistochemistry, we evaluated whether airway sections from CF and control subjects expressed markers of senescence, including p16INK4a(p16), a cyclin-dependent kinase inhibitor, phospho-Histone H2A.X (γH2A.X), and phospho-checkpoint 2 kinase (phospho-Chk2), which are also DNA damage response markers. Compared with airway epithelium from control subjects, CF airway epithelium had increased levels of expression of all three senescence markers. We hypothesized that the high load of NE in the CF airway triggers epithelial senescence by upregulating expression of p16, which inhibits cyclin-dependent kinase 4 (CDK4). Normal human bronchial epithelial (NHBE) cells, cultured in air-liquid interface were treated with NE (0, 200, and 500 nM) to induce visible injury. Total cell lysates were collected and evaluated by Western analysis for p16 protein expression and CDK4 kinase activity. NE significantly increased p16 expression and decreased CDK4 kinase activity in NHBE cells. These results support the concept that NE triggers expression of senescence markers in CF airway epithelial cells.
Sustained adenosine exposure causes lung endothelial apoptosis: a possible contributor to cigarette smoke-induced endothelial apoptosis and lung injury
Authors: Lu Qing , Sakhatskyy Pavlo , Newton Julie , Shamirian Paul , Hsiao Vivian , Curren Sean , Gabino Miranda Gustavo Andres , Pedroza Mesias , Blackburn Michael R. , Rounds Sharon
Published: January 2013

Pulmonary endothelial cell (EC) apoptosis has been implicated in the pathogenesis of emphysema. Cigarette smoke (CS) causes lung EC apoptosis and emphysema. In this study, we show that CS exposure increased lung tissue adenosine levels in mice, an effect associated with increased lung EC apoptosis and the development of emphysema. Adenosine has a protective effect against apoptosis via adenosine receptor-mediated signaling. However, sustained elevated adenosine increases alveolar cell apoptosis in adenosine deaminase-deficient mice. We established an in vitro model of sustained adenosine exposure by incubating lung EC with adenosine in the presence of an adenosine deaminase inhibitor, deoxycoformicin. We demonstrated that sustained adenosine exposure caused lung EC apoptosis via nucleoside transporter-facilitated intracellular adenosine uptake, subsequent activation of p38 and JNK in mitochondria, and ultimately mitochondrial defects and activation of the mitochondria-mediated intrinsic pathway of apoptosis. Our results suggest that sustained elevated adenosine may contribute to CS-induced lung EC apoptosis and emphysema. Our data also reconcile the paradoxical effects of adenosine on apoptosis, demonstrating that prolonged exposure causes apoptosis via nucleoside transporter-mediated intracellular adenosine signaling, whereas acute exposure protects against apoptosis via activation of adenosine receptors. Inhibition of adenosine uptake may become a new therapeutic target in treatment of CS-induced lung diseases.
Role of β-catenin-regulated CCN matricellular proteins in epithelial repair after inflammatory lung injury
Authors: Zemans Rachel L. , McClendon Jazalle , Aschner Yael , Briones Natalie , Young Scott K. , Lau Lester F. , Kahn Michael , Downey Gregory P.
Published: January 2013

Repair of the lung epithelium after injury is integral to the pathogenesis and outcomes of diverse inflammatory lung diseases. We previously reported that β-catenin signaling promotes epithelial repair after inflammatory injury, but the β-catenin target genes that mediate this effect are unknown. Herein, we examined which β-catenin transcriptional coactivators and target genes promote epithelial repair after inflammatory injury. Transmigration of human neutrophils across cultured monolayers of human lung epithelial cells resulted in a fall in transepithelial resistance and the formation of discrete areas of epithelial denudation (“microinjury”), which repaired via cell spreading by 96 h. In mice treated with intratracheal (i.t.) LPS or keratinocyte chemokine, neutrophil emigration was associated with increased permeability of the lung epithelium, as determined by increased bronchoalveolar lavage (BAL) fluid albumin concentration, which decreased over 3–6 days. Activation of β-catenin/p300-dependent gene expression using the compound ICG-001 accelerated epithelial repair in vitro and in murine models. Neutrophil transmigration induced epithelial expression of the β-catenin/p300 target genes Wnt-induced secreted protein (WISP) 1 and cysteine-rich (Cyr) 61, as determined by real-time PCR (qPCR) and immunostaining. Purified neutrophil elastase induced WISP1 upregulation in lung epithelial cells, as determined by qPCR. WISP1 expression increased in murine lungs after i.t. LPS, as determined by ELISA of the BAL fluid and qPCR of whole lung extracts. Finally, recombinant WISP1 and Cyr61 accelerated repair, and Cyr61-neutralizing antibodies delayed repair of the injured epithelium in vitro. We conclude that β-catenin/p300-dependent expression of WISP1 and Cyr61 is critical for epithelial repair and represents a potential therapeutic target to promote epithelial repair after inflammatory injury.
Genome-Wide Epigenetic Regulation of miRNAs in Cancer
Authors: Baer Constance , Claus Rainer , Plass Christoph
Published: January 2013

Aberrant microRNA (miRNA) expression contributes to tumorigenesis and cancer progression. Although the number of reported deregulated miRNAs in various cancer types is growing fast, the underlying mechanisms of aberrant miRNA regulation are still poorly studied. Epigenetic alterations including aberrant DNA methylation deregulate miRNA expression, which was first shown by reexpression of miRNAs upon pharmacologic DNA demethylation. However, studying the influence of DNA methylation on miRNA transcription on a genome-wide level was hampered by poor miRNA promoter annotation. Putative miRNA promoters were identified on a genome-wide level by using common promoter surrogate markers (e.g., histone modifications) and were later validated as such in different tumor entities. Integrating promoter datasets and global DNA methylation analysis revealed an extensive influence of DNA hyper- as well as hypomethylation on miRNA regulation. In this review, we summarize the current knowledge of the field and discuss recent efforts to map miRNA promoter sequences and to determine the contribution of epigenetic mechanisms to the regulation of miRNA expression. We discuss examples of tumor suppressive and oncogenic miRNAs such as the miR-34 and miR-21 family, respectively, which highlight the complexity and consequences of epigenetic miRNA deregulation. Cancer Res; 73(2); 473–7. ©2012 AACR.
Dual Programmed Cell Death Pathways Induced by p53 Transactivation Overcome Resistance to Oncolytic Adenovirus in Human Osteosarcoma Cells
Authors: Hasei Joe , Sasaki Tsuyoshi , Tazawa Hiroshi , Osaki Shuhei , Yamakawa Yasuaki , Kunisada Toshiyuki , Yoshida Aki , Hashimoto Yuuri , Onishi Teppei , Uno Futoshi , Kagawa Shunsuke , Urata Yasuo , Ozaki Toshifumi , Fujiwara Toshiyoshi
Published: January 2013

Tumor suppressor p53 is a multifunctional transcription factor that regulates diverse cell fates, including apoptosis and autophagy in tumor biology. p53 overexpression enhances the antitumor activity of oncolytic adenoviruses; however, the molecular mechanism of this occurrence remains unclear. We previously developed a tumor-specific replication-competent oncolytic adenovirus, OBP-301, that kills human osteosarcoma cells, but some human osteosarcoma cells were OBP-301–resistant. In this study, we investigated the antitumor activity of a p53-expressing oncolytic adenovirus, OBP-702, and the molecular mechanism of the p53-mediated cell death pathway in OBP-301–resistant human osteosarcoma cells. The cytopathic activity of OBP-702 was examined in OBP-301–sensitive (U2OS and HOS) and OBP-301–resistant (SaOS-2 and MNNG/HOS) human osteosarcoma cells. The molecular mechanism in the OBP-702–mediated induction of two cell death pathways, apoptosis and autophagy, was investigated in OBP-301–resistant osteosarcoma cells. The antitumor effect of OBP-702 was further assessed using an orthotopic OBP-301–resistant MNNG/HOS osteosarcoma xenograft tumor model. OBP-702 suppressed the viability of OBP-301–sensitive and -resistant osteosarcoma cells more efficiently than OBP-301 or a replication-deficient p53-expressing adenovirus (Ad-p53). OBP-702 induced more profound apoptosis and autophagy when compared with OBP-301 or Ad-p53. E1A-mediated miR-93/106b upregulation induced p21 suppression, leading to p53-mediated apoptosis and autophagy in OBP-702–infected cells. p53 overexpression enhanced adenovirus-mediated autophagy through activation of damage-regulated autophagy modulator (DRAM). Moreover, OBP-702 suppressed tumor growth in an orthotopic OBP-301–resistant MNNG/HOS xenograft tumor model. These results suggest that OBP-702–mediated p53 transactivation is a promising antitumor strategy to induce dual apoptotic and autophagic cell death pathways via regulation of miRNA and DRAM in human osteosarcoma cells. Mol Cancer Ther; 12(3); 314–25. ©2012 AACR.
Insulin-Like Growth Factors and Insulin-Like Growth Factor–Binding Proteins and Prostate Cancer Risk: Results from the Prostate Cancer Prevention Trial
Authors: Neuhouser Marian L. , Platz Elizabeth A. , Till Cathee , Tangen Catherine M. , Goodman Phyllis J. , Kristal Alan , Parnes Howard L. , Tao Yuzhen , Figg William D. , Lucia M. Scott , Hoque Ashraful , Hsing Ann W. , Thompson Ian M. , Pollak Michael
Published: January 2013

The role of the insulin-like growth factor (IGF) axis and whether IGFs interact with androgen-suppressing agents in relation to prostate carcinogenesis is unclear. This nested case–control study (n = 1,652 cases/1,543 controls) examined whether serum IGF1, IGF2, IGFBP2, IGFBP3, and the IGF1:IGFBP3 ratio were associated with prostate cancer in the Prostate Cancer Prevention Trial (PCPT), a randomized, placebo-controlled trial of finasteride for prostate cancer prevention. Presence or absence of cancer was determined by prostate biopsy. Baseline serum was assayed for IGF-axis analytes using ELISA. Logistic regression estimated ORs and 95% confidence intervals for risk of total, low-grade (Gleason 2–6) and high-grade (Gleason 7–10) cancers. Results were stratified by intervention assignment. In both the placebo and finasteride arms, serum IGF1, IGF2, IGFBP3, and the IGF1:IGFBP3 ratio were not associated with prostate cancer. However, men in the highest versus lowest quartile of serum IGFBP2 had a 48% (Ptrend = 0.02) and 55% (Ptrend = 0.01) increased risk for total and low-grade cancers, respectively. These IGFBP2 associations were attenuated and no longer statistically significant in the finasteride arm. Our results suggest that in general, serum IGF-axis analytes were not associated with prostate cancer risk in the PCPT in which presence or absence of all cancers was biopsy-determined. The exception was the finding that high serum IGFBP2 is a risk factor for low-grade disease, which was attenuated for men on finasteride. Further research is needed to understand better the risk incurred by high IGFBP2 and whether androgen-suppressing agents such as finasteride influence aspects of IGFBP2 physiology relevant to prostate carcinogenesis. Cancer Prev Res; 6(2); 91–9. ©2013 AACR.
Resequencing and Clinical Associations of the 9p21.3 Region
Authors: Johnson Andrew D. , Hwang Shih-Jen , Voorman Arend , Morrison Alanna , Peloso Gina M. , Hsu Yi-Hsiang , Thanassoulis George , Newton-Cheh Christopher , Rogers Ian S. , Hoffmann Udo , Freedman Jane E. , Fox Caroline S. , Psaty Bruce M. , Boerwinkle Eric , Cupples L. Adrienne , O’Donnell Christopher J.
Published: January 2013

Background—

9p21.3 is among the most strongly replicated regions for cardiovascular disease. There are few reports of sequencing the associated 9p21.3 interval. We set out to sequence the 9p21.3 region followed by a comprehensive study of genetic associations with clinical and subclinical cardiovascular disease and its risk factors, as well as with copy number variation and gene expression, in the Framingham Heart Study (FHS).

Methods and Results—

We sequenced 281 individuals (94 with myocardial infarction, 94 with high coronary artery calcium levels, and 93 control subjects free of elevated coronary artery calcium or myocardial infarction), followed by genotyping and association in >7000 additional FHS individuals. We assessed genetic associations with clinical and subclinical cardiovascular disease, risk factor phenotypes, and gene expression levels of the protein-coding genes
CDKN2A
and
CDKN2B
and the noncoding gene
ANRIL
in freshly harvested leukocytes and platelets. Within this large sample, we found strong associations of 9p21.3 variants with increased risk for myocardial infarction, higher coronary artery calcium levels, and larger abdominal aorta diameters and no evidence for association with traditional cardiovascular disease risk factors. No common protein-coding variation, variants in splice donor or acceptor sites, or copy number variation events were observed. By contrast, strong associations were observed between genetic variants and gene expression, particularly for a short isoform of
ANRIL
and for
CDKN2B
.

Conclusions—

Our thorough genomic characterization of 9p21.3 suggests common variants likely account for observed disease associations and provides further support for the hypothesis that complex regulatory variation affecting
ANRIL
and
CDKN2B
gene expression may contribute to increased risk for clinically apparent and subclinical coronary artery disease and aortic disease.
Prospective, Multicenter Study of Ventricular Assist Device Infections
Authors: Gordon Rachel J. , Weinberg Alan D. , Pagani Francis D. , Slaughter Mark S. , Pappas Pat S. , Naka Yoshifumi , Goldstein Daniel J. , Dembitsky Walter P. , Giacalone Julie C. , Ferrante Jennifer , Ascheim Deborah D. , Moskowitz Alan J. , Rose Eric A. , Gelijns Annetine C. , Lowy Franklin D. ,   Authors in the VAD Infection Study Group include:, Fox Sarah , Leventhal Christina L. , Gallagher Colleen , Idrissi Katharine , Flannery Margaret , Te-Frey Rosie , Swayze Roger , Adamson Robert M. , Jaski Brian E. , Gravitt Gina , Kohlmyer Chris , Chillcott Suzanne , Stahovich Marcia , Icenogle Timothy B. , Puhlman Mark , Tector Alfred , Miller Maggie , Edwards Niloo M. , Yakey Jan , Long Jim , Acker Michael , Donnelly Joseph P. , Dougherty Deb , Dowling Robert , Adkisson Pam
Published: January 2013

Background—

Ventricular assist devices (VADs) improve survival and quality of life in patients with advanced heart failure, but their use is frequently complicated by infection. There are limited data on the microbiology and epidemiology of these infections.

Methods and Results—

One hundred fifty patients scheduled for VAD implantation were enrolled (2006–2008) at 11 US cardiac centers and followed prospectively until transplantation, explantation for recovery, death, or for 1 year. Eighty-six patients (57%) received HeartMate II devices. Data were collected on potential preoperative, intraoperative, and postoperative risk factors for infection. Clinical, laboratory, and microbiological data were collected for suspected infections and evaluated by an infectious diseases specialist. Thirty-three patients (22%) developed 34 VAD-related infections with an incidence rate of 0.10 per 100 person-days (95% confidence interval, 0.073–0.142). The median time to infection was 68 days. The driveline was the most commonly infected site (n=28); 18 (64%) were associated with invasive disease. Staphylococci were the most common pathogen (47%), but pseudomonas or other Gram-negative bacteria caused 32% of infections. A history of depression and elevated baseline serum creatinine were independent predictors of VAD infection (adjusted hazard ratio=2.8 [
P
=0.007] and 1.7 [
P
=0.023], respectively). The HeartMate II was not associated with a decreased risk of infection. VAD infection increased 1-year mortality (adjusted hazard ratio=5.6;
P
<0.0001).

Conclusions—

This prospective, multicenter study demonstrates that infection frequently complicates VAD placement and is a continuing problem despite the use of newer, smaller devices. Depression and renal dysfunction may increase the risk of VAD infection. VAD infection is a serious consequence because it adversely affects patient survival.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT01471795.
Small Cloud Particle Shapes in Mixed-Phase Clouds
Authors: McFarquhar Greg M. , Um Junshik , Jackson Robert
Published: January 2013

The shapes of cloud particles with maximum dimensions Dmax between 35 and 60 μm in mixed-phase clouds were studied using high-resolution particle images collected by a cloud particle imager (CPI) during the Mixed-Phase Arctic Cloud Experiment (M-PACE) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC). The area ratio α, the projected area of a particle divided by the area of a circle with diameter Dmax, quantified particle shape. The differing optical characteristics of CPIs used in M-PACE and ISDAC had no effect on derived α provided that Dmax > 35 μm and CPI focus > 45. The fraction of particles with 35 < Dmax < 60 μm with α > 0.8 increased with the ratio of liquid water content (LWC) to total water content (TWC). The average αmean of small particles in each 10-s interval in mixed-phase clouds was correlated with LWC/TWC with a correlation coefficient of 0.60 for M-PACE and 0.43 for ISDAC. The stronger correlation seen during M-PACE was most likely associated with the presence of more liquid droplets that were larger than the CPI detection threshold contributing to αmean; the modal effective radius was larger (11 vs 6 μm), and drops with D > 35 μm had concentrations during M-PACE that were 6 times as large as those of ISDAC. This study hence suggests that area ratio can be used to identify the phase of particles with 35 < Dmax < 60 μm and questions the assumption used in previous studies that all particles in this size range are supercooled droplets.
A Nonparametric Approach to the Removal of Documented Inhomogeneities in Climate Time Series
Authors: Ambrosino Chiara , Chandler Richard E.
Published: January 2013

Climate data often suffer from artificial inhomogeneities, resulting from documented or undocumented events. For a time series to be used with confidence in climate analysis, it should only be characterized by variations intrinsic to the climate system. Many methods (e.g., direct or indirect) have been proposed according to the data characteristics (e.g., location, variable, or data completeness). This paper is focused on the abrupt-changes problem (when the properties of a time series change abruptly), when their timing is known, and suggests that a nonparametric regression framework provides an appealing way to correct for discontinuities in such a way as to recognize and allow for the existence of other structures such as seasonality and long-term smooth trends. The approach is illustrated by using reanalysis data for southern Africa, for which discontinuities are present because of the introduction of satellite technology in 1979.