bluuebunny/crossref_metadata_2025 huggingface dataset:
Rosiglitazone Ameliorates Diabetic Nephropathy by Inhibiting Reactive Oxygen Species and Its Downstream-Signaling Pathways
Authors: Bao Yan , Jia Ru-han , Yuan Jun , Li Jing
Published: May 2007

Aim: To study whether rosiglitazone prevents the development of diabetic nephropathy through reduction of reactive oxygen species and its downstream signal transduction pathways.Methods: The rats were intraperitoneally injected with streptozotocin to induce diabetes, meanwhile the rats in the therapeutic groups were given rosiglitazone (5 or 20 mg/kg/day) for 4 weeks by intragastric administration. Blood glucose, serum lipid and creatinine, urinary albumin excretion were measured. Malondialdehyde content, the activities of nuclear factor-ĸB (NF-ĸB), antioxidant enzymes including Cu-Zn SOD and GSH-Px in kidney were also measured. In addition, the mRNA and protein expression of MCP-1 were semiquantitatively determined with PT-PCR and immunohistochemical staining respectively. Results: No significant difference of blood glucose and lipid were found between diabetic rats and rosiglitazone treatment groups. The renal histopathology was improved significantly. The expressions of MCP-1 mRNA and protein, malondialdehyde level and the activity of NF-ĸB were decreased markedly in rats treated with high-dose rosiglitazone, but the activities of renal Cu-Zn SOD and GSH-Px increased significantly. Conclusions: Rosiglitazone treatment prevented glomerular injury in diabetic rats, which was closely related with its roles of reducing reactive oxygen species, NF-ĸB activation and MCP-1 expression in the early phase of diabetic nephropathy.
Concomitant Lower Serum Albumin and Vitamin D Levels Are Associated with Decreased Objective Physical Performance among Japanese Community-Dwelling Elderly
Authors: Kwon Jinhee , Suzuki Takao , Yoshida Hideyo , Kim Hunkyung , Yoshida Yuko , Iwasa Hajime
Published: May 2007

Background: Previous studies have shown that serum albumin or vitamin D is associated with physical performance. We hypothesized that older adults with concomitant lower serum albumin and vitamin D (25-hydroxyvitamin D, 25OHD) levels are associated with decreased physical performance compared to those with 1 or none of the 2 risk factors. Objective: To investigate the association of combined serum albumin and 25OHD levels with physical performance (muscle strength and balance capability) in community-dwelling elderly. Methods: A cross-sectional study in a community-based population in the province of Tokyo, Japan, was performed. For the study, 1,094 community-dwelling people aged 70 and older underwent an interview, anthropometric measurements, blood analysis and physical performance testing. The subjects were classified into 4 types by combining serum albumin and 25OHD levels: lower albumin only, lower vitamin D only, lower albumin and lower vitamin D, higher albumin and higher vitamin D. Results: Men with concomitant lower albumin and lower 25OHD levels had significantly decreased knee extension power, usual timed Up & Go and maximal timed Up & Go, even after adjusting for age and body mass index (BMI). In women, concomitant lower albumin and lower vitamin D was associated with significantly decreased handgrip strength and functional reach, even after adjusting for age and BMI. Subjects with combined lower albumin and lower vitamin D levels showed a significant decline in muscle strength and balance capability compared to higher albumin and higher vitamin D, even after adjusting for age, current drinking or smoking status, physical activity, history of chronic disease, basic activities of daily living, instrumental activities of daily living, BMI and bone mineral density. Conclusion: Concomitant lower serum albumin and lower vitamin D levels are associated with decreased muscle strength and balance capability in both men and women. These results suggest that serum albumin and 25OHD together may be an important target for strategies aiming to achieve a healthy life and prevent loss of independence in community-dwelling elderly.
Integrin-Linked Kinase at the Heart of Cardiac Contractility, Repair, and Disease
Authors: Hannigan Gregory E. , Coles John G. , Dedhar Shoukat
Published: May 2007

Recent advances in cardiac physiology identify the integrin-linked kinase (ILK) as an essential molecule regulating cardiac growth, contractility, and repair. A key transducer of biochemical signals initiated at the plasma membrane by cell–matrix interactions, ILK now emerges as a crucial player in mechanotransduction by integrins. Animal models have been particularly instructive in dissecting the cardiac functions of ILK and its associated proteins, such as parvins and PINCH, and have clearly established ILK as a major contributor to cardiac health. ILK gene knockouts in mice, flies, and worms result in early embryonic lethality because of cell adhesion defects and cytoskeletal disorganization. Although widely distributed in mammalian tissues, ILK expression is highest in the heart, and cardiac-specific ablation of ILK causes cardiomyopathy and sudden death in mice. ILK protein complexes are found in the sarcomere, which is the basic contractile unit of myocytes. A natural inactivating mutation in the kinase domain of ILK disrupts ILK protein interactions in the sarcomere, causing a contractile defect in the zebrafish heart. The relatively subtle phenotype of mutant ILK hearts, compared with ILK-ablated hearts, suggests multiple cardiac ILK functions. Cardiac-specific expression of ILK in transgenic mice induces a hypertrophic program, pointing to ILK as a proximal regulator of multiple hypertrophic signal transduction pathways. ILK protein interactions may also be important in mediating postinfarct cell migration and myocardial repair.
Programming Smooth Muscle Plasticity With Chromatin Dynamics
Authors: McDonald Oliver G. , Owens Gary K.
Published: May 2007

Smooth muscle cells (SMCs) possess remarkable phenotypic plasticity that allows rapid adaptation to fluctuating environmental cues. For example, vascular SMCs undergo profound changes in their phenotype during neointimal formation in response to vessel injury or within atherosclerotic plaques. Recent studies have shown that interaction of serum response factor (SRF) and its numerous accessory cofactors with CArG box DNA sequences within promoter chromatin of SMC genes is a nexus for integrating signals that influence SMC differentiation in development and disease. During development, SMC-restricted sets of posttranslational histone modifications are acquired within the CArG box chromatin of SMC genes. These modifications in turn control the chromatin-binding properties of SRF. The histone modifications appear to encode a SMC-specific epigenetic program that is used by extracellular cues to influence SMC differentiation, by regulating binding of SRF and its partners to the chromatin template. Thus, SMC differentiation is dynamically regulated by the interplay between SRF accessory cofactors, the SRF–CArG interaction, and the underlying histone modification program. As such, the inherent plasticity of the SMC lineage offers unique glimpses into how cellular differentiation is dynamically controlled at the level of chromatin within the context of changing microenvironments. Further elucidation of how chromatin regulates SMC differentiation will undoubtedly yield valuable insights into both normal developmental processes and the pathogenesis of several vascular diseases that display detrimental SMC phenotypic behavior.
Vascular Endothelial Growth Factor Is Induced by the Inflammatory Cytokines Interleukin-6 and Oncostatin M in Human Adipose Tissue In Vitro and in Murine Adipose Tissue In Vivo
Authors: Rega G. , Kaun C. , Demyanets S. , Pfaffenberger S. , Rychli K. , Hohensinner P.J. , Kastl S.P. , Speidl W.S. , Weiss T.W. , Breuss J.M. , Furnkranz A. , Uhrin P. , Zaujec J. , Zilberfarb V. , Frey M. , Roehle R. , Maurer G. , Huber K. , Wojta J.
Published: May 2007

Objectives—

It is believed that adipose tissue acts as an endocrine organ by producing inflammatory mediators and thereby contributes to the increased cardiovascular risk seen in obesity. A link between adipose tissue mass and angiogenesis has been suggested. Vascular endothelial growth factor (VEGF) seems to be implicated in this process. Members of the glycoprotein (gp)130 ligand family regulate VEGF expression in other cells.

Methods and Results—

We used tissue explants as well as primary cultures of preadipocytes and adipocytes from human subcutaneous and visceral adipose tissue to investigate whether the gp130 ligands oncostatin M (OSM), interleukin-6 (IL-6), leukemia inhibitory factor (LIF), and cardiotrophin-1 (CT-1) regulate VEGF expression in human adipose tissue. Human subcutaneous and visceral adipose tissue responded to treatment with IL-6 and OSM with a significant increase in VEGF production. Human preadipocytes were isolated from subcutaneous and visceral adipose tissue. Adipocyte-differentiation was induced by hormone-supplementation. All cell types responded to IL-6 and OSM with a robust increase in VEGF protein production and a similar increase in VEGF-specific mRNA. Furthermore, IL-1β synergistically enhanced the effect of OSM on VEGF production. AG-490, a JAK/STAT inhibitor, abolished the OSM-dependent VEGF induction almost completely. In mice, IL-6 and OSM increased serum levels of VEGF and VEGF mRNA and vessel density in adipose tissue.

Conclusion—

We speculate that the inflammatory cytokines IL-6 and OSM might support angiogenesis during adipose tissue growth by upregulating VEGF.
Increased Inhibition of Inward Rectifier K
+
Channels by Angiotensin II in Small-Diameter Coronary Artery of Isoproterenol-Induced Hypertrophied Model
Authors: Park Won Sun , Ko Jae-Hong , Kim Nari , Son Youn Kyoung , Kang Sung Hyun , Warda Mohamad , Jung In Duk , Park Yeong-Min , Han Jin
Published: May 2007

Objective—

We investigated the effects of angiotensin II (Ang II) on inward rectifier K
+
(Kir) channels in small-diameter coronary arterial smooth muscle cells (SCASMCs) of control and isoproterenol (Iso)-induced hypertrophied rabbits.

Methods and Results—

Kir current amplitude and Kir channel protein expression were definitely lower in the Iso-induced hypertrophied model than in the control. In a pressurized arterial experiment, 15 mmol/L K
+
-induced vasodilation was greater in the control arteries than in the arteries of Iso-induced hypertrophied model. Ang II reduced the Kir current in a concentration-dependent manner, and this inhibition was greater in SCASMCs from Iso-induced hypertrophied model than from control. Although, there was no difference in the expression of Ang II type 2 (AT
2
) receptor between SCASMCs of control and Iso-induced hypertrophied model, the expression of Ang II type 1 (AT
1
) receptor and phosphorylated PKCα were greater in SCASMCs of Iso-induced hypertrophied model than of control.

Conclusion—

Ang II inhibits Kir channels more prominently in SCASMCs of Iso-induced hypertrophied model owing to increases in the expression of AT
1
receptor and the activation of PKCα. Our findings about the differential expression of Kir channels and different modulation of Kir channels by a vasoconstrictor (Ang II) in a hypertrophy model are important for better understanding the responsiveness of small-diameter arteries during hypertrophy.
A Discussion of Flow Pathways in the Central and Eastern Equatorial Pacific
Authors: Brown Jaclyn N. , Godfrey J. Stuart , Schiller Andreas
Published: May 2007

An eddy-permitting global ocean model is used to interpret kinematics within the central and eastern equatorial Pacific Ocean, from 160°E to the coast of America. Because of high levels of variability in this region, observational studies of meridional flow are contradictory, in particular as to whether the net flow is northward or southward. Unlike most oceanographic datasets, model output can be analyzed at high temporal and spatial resolution, providing clues as to real ocean behavior. In the model, a net southward flow occurs across the equator east of 160°W, at most density layers throughout the year. In the central Pacific, from 160°E to 160°W, the net flow is northward but varies with season and occurs primarily in the mixed layer. This is a key region for the flow of Equatorial Undercurrent water into the Northern Hemisphere. The three-dimensional flow is very complex and seasonally dependent. It is vital that these flows are analyzed in an isopycnal framework, or else the pathways are very misleading. In the first half of the year, evidence is found of meridional tropical cells on either side of the equator out to ±5°. These cells appear to exist without any need for diapycnal downwelling. In the second half of the year, when tropical instability waves are active, the cells are overlaid by a strong surface southward flow that appears to be a bolus-type transport. This transport is not apparent unless the flow is calculated in the aforementioned manner.
On the Reflectance of Uniform Slopes for Normally Incident Interfacial Solitary Waves
Authors: Bourgault Daniel , Kelley Daniel E.
Published: May 2007

The collision of interfacial solitary waves with sloping boundaries may provide an important energy source for mixing in coastal waters. Collision energetics have been studied in the laboratory for the idealized case of normal incidence upon uniform slopes. Before these results can be recast into an ocean parameterization, contradictory laboratory findings must be addressed, as must the possibility of a bias owing to laboratory sidewall effects. As a first step, the authors have revisited the laboratory results in the context of numerical simulations performed with a nonhydrostatic laterally averaged model. It is shown that the simulations and the laboratory measurements match closely, but only for simulations that incorporate sidewall friction. More laboratory measurements are called for, but in the meantime the numerical simulations done without sidewall friction suggest a tentative parameterization of the reflectance of interfacial solitary waves upon impact with uniform slopes.
Climate Variability in the Equatorial Pacific Ocean Induced by Decadal Variability of Mixing Coefficient
Authors: Huang Chuan Jiang , Wang Wei , Huang Rui Xin
Published: May 2007

The circulation in the equatorial Pacific Ocean is studied in a series of numerical experiments based on an isopycnal coordinate model. The model is subject to monthly mean climatology of wind stress and surface thermohaline forcing. In response to decadal variability in the diapycnal mixing coefficient, sea surface temperature and other properties of the circulation system oscillate periodically. The strongest sea surface temperature anomaly appears in the geographic location of Niño-3 region with the amplitude on the order of 0.5°C, if the model is subject to a 30-yr sinusoidal oscillation in diapycnal mixing coefficient that varies between 0.03 × 10−4 and 0.27 × 10−4 m2 s−1. Changes in diapycnal mixing coefficient of this amplitude are within the bulk range consistent with the external mechanical energy input in the global ocean, especially when considering the great changes of tropical cyclones during the past decades. Thus, time-varying diapycnal mixing associated with changes in wind energy input into the ocean may play a nonnegligible role in decadal climate variability in the equatorial circulation and climate.
Oceanic Isopycnal Slope Spectra. Part II: Turbulence
Authors: Klymak Jody M. , Moum James N.
Published: May 2007

Isopycnal slope spectra were computed from thermistor data obtained using a microstructure platform towed through turbulence generated by internal tidal motions near the Hawaiian Ridge. The spectra were compared with turbulence dissipation rates ɛ that are estimated using shear probes. The turbulence subrange of isopycnal slope spectra extends to surprisingly large horizontal wavelengths (>100 m). A four-order-of-magnitude range in turbulence dissipation rates at this site reveals that isopycnal slope spectra ∝ ɛ2/3k1/3x. The turbulence spectral subrange (kx > 0.4 cpm) responds to the dissipation rate as predicted by the Batchelor model spectrum, both in amplitude and towed vertical coherence. Scales between 100 and 1000 m are modeled by a linear combination of internal waves and turbulence while at larger scales internal waves dominate. The broad bandwidth of the turbulence subrange means that a fit of spectral amplitude to the Batchelor model yields reasonable estimates of ɛ, even when applied at scales of tens of meters that in vertical profiles would be obscured by other fine structure.
Relationship between Anti-felting Properties and Physicochemical Properties of Wool Fibers Treated with Ar-plasma
Authors: Mori Masukuni , Inagaki Norihiro
Published: May 2007

The anti-felting mechanism of plasma-treated wool was investigated by analyzing the surface of Ar-plasma-treated wool using XPS. The changes of single fibers and the properties of their assemblies were also studied. It was suggested that intermediate cystine oxides, i.e., S(O)—S and S(O)2—S groups generated on the wool fiber surface, have a strong affinity with water. In addition, carboxyl and sulphonic acid groups produced on the fiber surface during plasma treatment may also increase surface hydration and thus may play some part in the felting behavior of wool fiber. Subsequently, cohesive force is exerted by hydrogen bonding between these groups and water molecules on the fiber surfaces. This interaction results in a decrease in the flexibility of the individual fibers in the assembly. This limits the unidirectional movement of the fibers and thus improves the anti-felting behavior of the wool fibers.
Cognitive Profiles and Visuoperceptual Abilities in Preterm and Term Spastic Diplegic Children With Periventricular Leukomalacia
Authors: Pagliano Emanuela , Fedrizzi Ermellina , Erbetta Alessandra , Bulgheroni Sara , Solari Alessandra , Bono Renata , Fazzi Elisa , Andreucci Elena , Riva Daria
Published: May 2007

Although relations between the extent of periventricular leukomalacia and neuropsychological performance in preterm children with spastic diplegia have been extensively investigated, studies on term children with spastic diplegia are rare. The authors examined 15 preterm children and 9 term children with spastic diplegia, all of whom had periventricular leukomalacia as a main magnetic resonance imaging (MRI) finding (excluding full-term spastic diplegic children with other MRI findings). Cognitive abilities (Griffith scale) and visuoperceptual abilities (Developmental Test of Visual Perception) were compared in the 2 groups and related to periventricular leukomalacia severity. Cognitive performance was substantially similar in the 2 groups. However, the overall Developmental Test of Visual Perception scores were below normal in the preterm and were normal in the term children; furthermore, visuoperceptual abilities were differentially affected in the preterm children, with visuomotor abilities more compromised than nonmotor visuoperceptual abilities. These children had similar cognitive performance and MRI findings, so the greater visuoperceptual compromise in the preterm group suggests a direct influence of prematurity, which may have adversely influenced the reorganization of visual centers and pathways following the initial developmental insult. The strabismus present in most preterm children would also have contributed to their greater visuoperceptual compromise. The authors conclude that the management of preterm and term children should differ, with concentration on visuoperceptual skills and rehabilitation in the former.
Isolated Intracranial Hypertension as a Late Manifestation of Sinus Venous Compression Secondary to a Depressed Skull Fracture
Authors: Dabscheck Gabriel , Mackay Mark , Coleman Lee , Lo Patrick
Published: May 2007

Cerebral venous sinus compression can mimic idiopathic intracranial hypertension. The authors report the case of a 12-year-old girl who presented with diplopia and papilledema 3 weeks after a head injury. Lumbar puncture confirmed raised intracranial pressure, and neuroimaging subsequently identified a skull fracture compressing the right transverse sinus. Papilledema and diplopia resolved following surgical elevation of the bone fragment. Computer tomography or magnetic resonance venography are indicated in children presenting with isolated intracranial hypertension following head injury to exclude cerebral venous sinus compression secondary to skull fracture.
A Damage-coupled Criterion of Localized Necking Based on Acoustic Tensor
Authors: Chow C.L. , Jie M. , Wu X.
Published: May 2007

The development of a localized necking criterion for strain-softening materials is presented. The criterion is applicable to materials with anisotropic damage and anisotropic plasticity. The critical condition of damage evolution leading to localized necking is of primary interest in this investigation. As a consequence of plastic instability, the singularity of acoustic tensor is taken as the critical condition for localized necking in strain-softening materials, which often occurs prior to fracture. Effective tangent modulus tensor for materials with anisotropic damage is established. The damage-coupled localized necking criterion, along with the inclination angle of localization band, for strain-softening materials is derived. The closed-form expression of the localized necking criterion has potential applications in the failure analysis of strain-softening materials such as hot metals, rocks, soil, solder, etc. Tensile testing at elevated temperature (450°C) has been performed for aluminum alloy Al6061 with multiple unloading paths to determine material damage. The test results displaying the strain-softening and material damage behaviors are employed to formulate the constitutive equations of the material. Forming limit strains for a particular loading path are computed and compared with the test result.
Comparison of Computed Tomography Angiography to Contrast Arteriography for Patients Undergoing Evaluation for Lower Extremity Revascularization
Authors: Hingorani Anil , Ascher Enrico , Marks Natalie , Mutyala Manykiam , Shiferson Alexander , Flyer Mark , Jacob Theresa
Published: May 2007

In an effort to explore alternatives to contrast arteriography, we compared computed tomography angiography to contrast arteriography for defining anatomic features of patients undergoing lower extremity revascularization. From November 2003 to March 2004, 36 inpatients with chronic lower extremity ischemia underwent contrast arteriography and computed tomography angiography before undergoing lower extremity revascularization procedures. A Siemens 16 slice multiplanar computed tomography device with bolus tracking was used for these exams. The reports of these tests and images were compared prospectively, and the differences in the aorto-iliac segment, femoral-popliteal, and infrapopliteal segments were noted. The vessels were classified as mild disease (<50%), moderate disease (50%-70%), severe (71%-99%), and occluded. The studies and treatment plans based on these data were compared. The mean age was 76 ± 12 years (SD). Indications for the procedures included gangrene (45%), ischemic ulcer (32%), rest pain (19%), and severe claudication (3%); 69% were diabetics. Accuracy of computed tomography angiography in the aorto-iliac, femoral-popliteal, and infrapopliteal segments was 100%, 81%, and 59%, respectively. Thirteen of 18 (72%) of these disagreements resulted in a different procedure than that suggested by computed tomography angiography. A review of the data obtained in this series indicated that computed tomography angiography appears to be unable to obtain adequate information in this highly selected population at our institution.
Thrombus and Calcium in Aortic Aneurysm Necks: Validation of a Scoring System in a Dutch Cohort Study
Authors: Tournoij Erik , Slisatkorn Worawong , Prokop Matthias , Verhagen Hence J. M. , Moll Frans L.
Published: May 2007

This study was conducted to validate a proposed classification system on the characteristics of the abdominal aortic aneurysm neck. The cohort comprised 100 consecutive patients who underwent open or endovascular aneurysm repair. Aneurysm neck characteristics of diameter, calcium, thrombus, and angulation were reviewed. The presence of calcium at the aortic aneurysm wall was associated with lower body mass index. Thrombus was found in 52% of the patients. Hypertension was correlated with the presence of aortic wall thrombus. At the renal artery level, angulation was anterior in 56%, right lateral in 39%, and left lateral in 27%. At the origin of the aneurysm, angulation was posterior in 76%, right lateral in 46%, and left lateral in 42%. A wide variety in these characteristics was found. A scoring system allows comparison of patient characteristics in studies describing the clinical outcome of endovascular aneurysm repair and should be included in study reports.
Inhibition of sulfur mustard-induced cytotoxicity and inflammation by the macrolide antibiotic roxithromycin in human respiratory epithelial cells
Authors: Gao Xiugong , Ray Radharaman , Xiao Yan , Barker Peter E , Ray Prabhati
Published: May 2007

Background

Sulfur mustard (SM) is a potent chemical vesicant warfare agent that remains a significant military and civilian threat. Inhalation of SM gas causes airway inflammation and injury. In recent years, there has been increasing evidence of the effectiveness of macrolide antibiotics in treating chronic airway inflammatory diseases. In this study, the anti-cytotoxic and anti-inflammatory effects of a representative macrolide antibiotic, roxithromycin, were tested in vitro using SM-exposed normal human small airway epithelial (SAE) cells and bronchial/tracheal epithelial (BTE) cells. Cell viability, expression of proinflammatory cytokines including interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor (TNF), and expression of inducible nitric oxide synthase (iNOS) were examined, since these proinflammatory cytokines/mediators are import indicators of tissue inflammatory responses. We suggest that the influence of roxithromycin on SM-induced inflammatory reaction could play an important therapeutic role in the cytotoxicity exerted by this toxicant.

Results

MTS assay and Calcein AM/ethidium homodimer (EthD-1) fluorescence staining showed that roxithromycin decreased SM cytotoxicity in both SAE and BTE cells. Also, roxithromycin inhibited the SM-stimulated overproduction of the proinflammatory cytokines IL-1β, IL-6, IL-8 and TNF at both the protein level and the mRNA level, as measured by either enzyme-linked immunosorbent assay (ELISA) or real-time RT-PCR. In addition, roxithromycin inhibited the SM-induced overexpression of iNOS, as revealed by immunocytochemical analysis using quantum dots as the fluorophore.

Conclusion

The present study demonstrates that roxithromycin has inhibitory effects on the cytotoxicity and inflammation provoked by SM in human respiratory epithelial cells. The decreased cytotoxicity in roxithromycin-treated cells likely depends on the ability of the macrolide to down-regulate the production of proinflammatory cytokines and/or mediators. The results obtained in this study suggest that macrolide antibiotics may serve as potential vesicant respiratory therapeutics through mechanisms independent of their antibacterial activity.
CXC-chemokine regulation and neutrophil trafficking in hepatic ischemia-reperfusion injury in P-selectin/ICAM-1 deficient mice
Authors: Monson Keith M , Dowlatshahi Shadi , Crockett Elahé T
Published: May 2007

Background

Neutrophil adhesion and migration are critical in hepatic ischemia and reperfusion injury (I/R). P-selectin and the intercellular adhesion molecule (ICAM)-1 can mediate neutrophil-endothelial cell interactions, neutrophil migration, and the interactions of neutrophils with hepatocytes in the liver. Despite very strong preclinical data, recent clinical trials failed to show a protective effect of anti-adhesion therapy in reperfusion injury, indicating that the length of injury might be a critical factor in neutrophil infiltration. Therefore, the aim of this study was to assess the role of P-selectin and ICAM-1 in neutrophil infiltration and liver injury during early and late phases of liver I/R.

Methods

Adult male wild-type and P-selectin/ICAM-1-deficient (P/I null) mice underwent 90 minutes of partial liver ischemia followed by various periods of reperfusion (6, 15 h, and a survival study). Liver injury was assessed by plasma level of alanine aminotransferase (ALT) and histopathology. The plasma cytokines, TNF-α, IL-6, MIP-2 and KC, were measured by ELISA.

Results

Reperfusion caused significant hepatocellular injury in both wild-type and P/I null mice as was determined by plasma ALT levels and liver histopathology. The injury was associated with a marked neutrophil infiltration into the ischemic livers of both wild-type and P/I null mice. Although the levels of ALT and neutrophil infiltration were slightly lower in the P/I null mice compared with the wild-type mice the differences were not statistically significant. The plasma cytokine data of TNF-α and IL-6 followed a similar pattern to ALT data, and no significant difference was found between the wild-type and P/I null groups. In contrast, a significant difference in KC and MIP-2 chemokine levels was observed between the wild-type and P/I null mice. Additionally, the survival study showed a trend towards increased survival in the P/I null group.

Conclusion

While ICAM-1 and P-selectin does not appear to be critical for neutrophil infiltration and I/R injury in the liver, they may regulate CXC-chemokine production. Blockage of these adhesion molecules may improve survival and remote organ injury that often accompanies liver I/R injury, through chemokine regulation.
Optimizing involute gear design for maximum bending strength and equivalent pitting resistance
Authors: Spitas V , Spitas C
Published: May 2007

Standard involute gear designs dominate high-power transmission applications because they combine sufficient bending strength with high pitting resistance, while retaining an adequate contact ratio. In this paper, a non-standard, optimal alternative involute gear design has been presented, which has the same pitting resistance as the standard involute gears but exhibits maximum resistance to bending. The optimization procedure is based on the complex algorithm, where the root stress, as calculated through tabulated boundary element analysis values, is the objective function and the active constraints include all of the kinematical, manufacturing and geometrical conditions, which must be satisfied by the optimal design, including the pitting resistance. The results indicate that optimal designs can achieve up to 8.5 per cent reduction of the fillet stress. Two-dimensional photoelasticity was used to verify the optimization results.
To Knot or Not to Knot? Sutureless Haemostasis Compared to the Surgeon's Knot
Authors: Rajbabu K , Barber NJ , Choi W , Muir GH
Published: May 2007

INTRODUCTION

The aim of this study was to carry out an independent evaluation of the efficacy and security of a number of vessel ligation devices and ligatures.

MATERIALS AND METHODS

A vascular ligation model was devised using fresh, ex vivo porcine internal carotid arteries of varying external diameters. Coloured normal saline was infused via a pressure/monitor device through the artery. The end lumen was occluded by five different techniques: (i) braided suture in a surgeon's knot; (ii) a monofilament suture in a granny knot; (iii) a metallic clip (Ligaclip, Johnson and Johnson); (iv) a bipolar diathermy system (Ligasure, ValleyLab); and (v) an ultrasonically activated scalpel (Harmonic Scalpel, Johnson and Johnson). The vessels were subjected to supraphysiological pressures. Loss of haemostasis was evident by leakage of coloured perfusion fluid.

RESULTS

Secure haemostasis was obtained with all the techniques in all vessels below 5 mm in diameter. In vessels over 5 mm, secure haemostasis was obtained with all modalities except harmonic scalpel. With the harmonic scalpel, leaks occurred in 3/27 (11%) vessels between 5–6 mm and 3/5 (60%) vessels over 6 mm, confirming the manufacturer's instructions.

CONCLUSIONS

In this first, independent, randomised study comparing vessel ligation devices and ligatures, the manufacturer's claims for each of the haemostatic methods were accurate. We find that all the modalities tested perform as well as the traditional surgeon's knot in vessels of 5 mm and below.
Errors in a Stat Laboratory: Types and Frequencies 10 Years Later
Authors: Carraro Paolo , Plebani Mario
Published: May 2007

Background: In view of increasing attention focused on patient safety and the need to reduce laboratory errors, it is important that clinical laboratories collect statistics on error occurrence rates over the whole testing cycle, including pre-, intra-, and postanalytical phases.

Methods: The present study was conducted in 2006 according to the design we previously used in 1996 to monitor the error rates for laboratory testing in 4 different departments (internal medicine, nephrology, surgery, and intensive care). For 3 months, physicians and nurses were asked to pay careful attention to all test results. Any suspected laboratory error was recorded with associated pertinent clinical information. Every day, a laboratory physician visited the 4 departments and a critical appraisal was made of any suspect results.

Results: Among a total of 51 746 analyses, clinicians notified us of 393 questionable findings, 160 of which were confirmed as laboratory errors. The overall frequency of errors, 3092 ppm, was significantly lower (P <0.05) than in 1996 (4700 ppm). Of the 160 confirmed errors, 61.9% were preanalytical errors, 15% were analytical, and 23.1% were postanalytical.

Conclusions: During the last decade the error rates in our stat laboratory have been reduced significantly. As demonstrated by the distribution pattern, the pre- and postanalytical steps still have the highest error prevalences, but changes have occurred in the types and frequencies of errors in these phases of testing.
The development of SARS vaccine in China A reflection on public and private sector roles
Authors: Shen Xiaobai , Duan Yibing , Zhang Siguang
Published: May 2007

This paper explores the growing phenomenon of public and private partnerships (PPPs) in developing public goods through a study of a particular instance in the development of SARS vaccine in China. The case highlights the factors shaping this development: The specific nature of SARS
vaccine as a public good which differs from other medical products as well as the social, economic and political context in China where this development takes place. Our observation points to the pivotal elements of PPP in drawing upon complementary resources for technology development especially
in a developing country like China: The complexity of motives and incentives of individual actors, the governance and organisation of the partnership, and the role of the Chinese government. The case also draws our attention to the different nature of partnership, which may have impacts on
the choice of technology, the length of R&D process and long or short term effects to the society.
Ethnocultural Aspects of Suicide in Young People: A Systematic Literature Review Part 1: Rates and Methods of Youth Suicide
Authors: Colucci Erminia , Martin Graham
Published: May 2007

The study of ethnocultural aspects of suicidal behaviour is, at the moment, still a neglected area. The relatively few studies available are mainly on adults; young people usually are not examined separately. The authors reviewed 82 publications on youth suicide that have addressed, to different degrees, the ethnicity/culture of the population studied. Following a description of the main characteristics shared by these researches (e.g., predominance of studies on Blacks, Whites, and Hispanics; lack of qualitative methodology, etc.), the rates and methods of youth suicide, from a cross‐cultural perspective are discussed.
A Multicenter Randomized Controlled Trial of Motivational Interviewing in Teenagers With Diabetes
Authors: Channon Sue J. , Huws-Thomas Michelle V. , Rollnick Stephen , Hood Kerenza , Cannings-John Rebecca L. , Rogers Carol , Gregory John W.
Published: May 2007

OBJECTIVE—We sought to examine the efficacy of motivational interviewing with teenagers aged 14–17 years with type 1 diabetes.

RESEARCH DESIGN AND METHODS—In a randomized controlled trial analyzed by intention to treat, 66 teenagers with type 1 diabetes attending diabetes clinics in South Wales, U.K., were randomly assigned to the intervention group (38) and control group (28). Teenagers in the intervention group received motivational interviewing, and the control group received support visits. All participants received individual sessions over 12 months. The main outcome measures assessed at baseline, 6, 12, and 24 months were serum A1C and psychosocial self-report questionnaires including quality of life and well-being measures.

RESULTS—At 12 months, 60 patients had complete data. At the end of the intervention (12 months), the mean A1C in the motivational interviewing group was significantly lower than in the control group (P = 0.04), after adjusting for baseline values. At 24 months (when n = 47), this difference in A1C was maintained (P = 0.003). There were differences in psychosocial variables at 12 months, with the motivational interviewing group indicating more positive well-being, improved quality of life, and differences in their personal models of illness (all P < 0.01). Some of these differences were maintained at 24 months.

CONCLUSIONS—Motivational interviewing can be an effective method of facilitating behavioral changes in teenagers with type 1 diabetes with subsequent improvement in their glycemic control.
Computer Modeling of Diabetes and Its Complications
Authors:   The Mount Hood 4 Modeling Group
Published: May 2007

Computer simulation models are mathematical equations combined in a structured framework to represent some real or hypothetical system. One of their uses is to allow the projection of short-term data from clinical trials to evaluate clinical outcomes and costs over a long-term period. This technology is becoming increasingly important to assist decision making in modern medicine in situations where there is a paucity of long-term clinical trial data, as recently acknowledged in the American Diabetes Association Consensus Panel Guidelines for Computer Modeling of Diabetes and its Complications. The Mount Hood Challenge Meetings provide a forum for computer modelers of diabetes to discuss and compare models and identify key areas of future development to advance the field. The Fourth Mount Hood Challenge in 2004 was the first meeting of its kind to ask modelers to perform simulations of outcomes for patients in published clinical trials, allowing comparison against “real life” data. Eight modeling groups participated in the challenge. Each group was given three of the following challenges: to simulate a trial of type 2 diabetes (CARDS [Collaborative Atorvastatin Diabetes Study]); to simulate a trial of type 1 diabetes (DCCT [Diabetes Control and Complications Trial]); and to calculate outcomes for a hypothetical, precisely specified patient (cross-model validation). The results of the models varied from each other and for methodological reasons, in some cases, from the published trial data in important ways. This approach of performing systematic comparisons and validation exercises has enabled the identification of key differences among the models, as well as their possible causes and directions for improvement in the future.
Allgemeine Methodik für die Erstellung von Ökoinventaren im Bereich Holzproduktion | General Methodology for the Setting-up of a Life Cycle Inventory in the Field of Timber Production
Authors: Brunner Markus
Published: May 2007

A life cycle inventory (eco-inventory) as principal component of the eco-balance captures the energetic, material and non-material flows generated by the system. The eco-inventory of a timber production system is presented by means of internal flows as well as flows surpassing the limits of the system.
Komponentenbasierte Softwareentwicklung –neue Perspektiven für forstliche Modellierung und Informationsverarbeitung | Component-based software development –new perspectives for modelling in forestry and information processing
Authors: Lemm Renato , Erni Vinzenz , Thees Oliver
Published: May 2007

Software products are becoming increasingly essential in forestry. Lack of computer specialists and inadequate software technologies impede the development of tailor-made and economical software. We show the favourable conditions and possibilities for the development of component based software (e.g. COM), which enable the development of software, especially geared to forestry applications.
Produzione di parquet a partire da legname di castagno proveniente da boschi cedui del Sud delle Alpi | Production of parquet flooring using chestnut timber from coppices in southern Switzerland
Authors: Fonti Patrick , Giudici Fulvio
Published: May 2007

This study verified the opportunity of using graded chestnut timber collected in two coppice forests from the southern side of the Swiss Alps for the production of friezes(row flooring boards) and parquet. Therefore data provided along the chain of production, considering both processing yields and rejects, were collected; and on the same time the technical feasibility of producing these products was also evaluated.
The past, present and future of hypertension management: a potential role for AT1-receptor antagonists
Authors: Hollenberg Norman K , Sever Peter S
Published: May 2007

The benefits of effective antihypertensive treatment were established at least 40 years ago, but despite the availability of more reliable and better-tolerated antihypertensive drugs, the control of blood pressure remains poor in most patients. Long-term antihypertensive efficacy requires treatment that combines reliable 24-hour reduction of blood pressure with good tolerability to facilitate patient compliance.Treatment should also protect against target-organ damage.As the majority of negative cardiovascular effects of angiotensin II are mediated through the angiotensin II type 1 (AT1) receptor, specific blockade of this receptor is a rational approach for achieving these ideals. Several AT1-receptor blockers have been developed that combine antihypertensive efficacy and placebo-like tolerability — the latter being unique in the history of antihypertensive therapy. In experimental animals these drugs prevent or reverse target organ damage in the heart, the vasculature and the kidney. Ongoing large-scale outcome studies are now underway to establish the benefits of AT1-receptor blockade beyond blood pressure control.
Nitric oxide mediates inhibitory effect of losartan on angiotensin-induced contractions in hamster but not rat aorta
Authors: Inoue Kiyo , Nishimura Hikaru , Kubota Jiro , Kitaura Yasushi
Published: May 2007

We investigated a possible contribution of nitric oxide (NO) and prostaglandins to the inhibitory effect of losartan on contractions to Ang I (10-6 M) and Ang II (10 -7 M) with or without L-NAME (10-4 M) or indomethacin (10 -5 M) in the aorta of WKY, SHR and hamster (n=7 each). Rings of thoracic aorta (2-mm long) were placed in a myograph (5 ml). Endothelium-dependent vasodilations were evaluated with acetylcholine (10-8 ~ 10 -6 M). After a 45-minute incubation with L-NAME under a resting tension of 2 g, only hamster aorta contracted (p<0.01). The SHR aorta showed impaired relaxations to acetylcholine compared with the WKY and hamster aorta (p<0.05). Despite the difference in the stimulated NO release, losartan completely abolished the responses to Ang I and Ang II both in WKY and SHR vessels irrespective of the presence of L-NAME. In contrast to the rat aorta, the inhibitory effect of losartan was attenuated in the presence of L-NAME in the hamster aorta (78% vs 99% inhibition, p<0.05). Indomethacin did not alter the effect of losartan in any vessels. Our results suggest that the presence of NO, particularly a basal secretion of NO, is necessary for the full expression of the inhibitory effect of losartan in the hamster, but not in WKY or SHR, aorta. Unlike NO, prostaglandins do not appear to play a role in the effect of losartan.
Angiotensin II does not mediate the pressor response to PGD2 (icv)
Authors: Kershenovich Amir , Terrell Mary Lee , Summy-Long Joan Y , Kadekaro Massako
Published: May 2007

The objective of the present studies was to examine the interaction between brain-derived angiotensin II (Ang II) and prostaglandins in order to identify the mechanisms mediating the pressor response produced by these neuroregulators. Inhibiting synthesis of prostaglandins with indomethacin [indocin, 200 µg/ 5 µl artificial cerebrospinal fluid (aCSF)], administered intracerebroventricularly (icv) to conscious adult male Sprague-Dawley rats, reduced blood pressure to values below basal levels. When injected prior to Ang II (50 ng/5 µl aCSF; icv), indomethacin completely abolished the pressor response induced by the octapeptide. The increase in blood pressure produced by prostaglandin D2 (PGD 2, 20 µg/5 µl; icv), the most prominent prostaglandin in the rat brain, however, was not prevented by losartan (25 µg/5 µl; icv), an Ang II AT 1-receptor antagonist. Collectively, these results indicate that prostaglandins produced tonically in the brain maintain resting arterial blood pressure and that the pressor action of Ang II is dependent on de novo synthesis of a prostaglandin.
Angiotensin II binding and extracellular matrix remodelling in a rat model of myocardial infarction
Authors: El-Sabban Marwan E , Hassan Khaled A , Birbari Adel E , Bitar Khalil M , Bikhazi Anwar B
Published: May 2007

Clinical evidence points to a role for angiotensin II (Ang II) in the post-infarction remodelling of cardiac hypertrophy. The present study was designed to investigate the remodelling process in an animal model of myocardial infarction (MI) using the following criteria: 1) histological studies to examine the re-vascularisation process and collagen deposition in different regions of the myocardium; 2) histological evidence to investigate the cell type distribution using cell-specific markers; 3) histological and Western blot analysis to localise Ang II receptor subtypes (AT1-receptor and AT2-receptor) and to study their regulation; 4) kinetics of the binding of Ang II to its receptors in a heart perfusion model; and 5) to assess the effect of the Ang II antagonist (losartan) on these parameters.

MI was induced by ligation of the left anterior descending coronary artery of Sprague-Dawley rats. Four different animal groups were established: 1) sham-operated, non-treated; 2) sham-operated, treated with losartan; 3) myocardial infarct, non-treated; and

4) myocardial infarct, treated with losartan. In infarcted rat hearts, fibroblasts and collagen types I and III increased in the remnant viable region of the left ventricle compared with sham-operated rats. One month of losartan treatment in myocardial infarcted rats revealed insignificant changes in fibroblasts and collagen types I and III compared with sham controls. Also, myocardial infarction increased AT1-receptor protein levels compared with sham-operated controls, as judged by Western blotting. In losartan-treated myocardial infarct animals, no changes were detected at the level of AT1-receptor expression compared with non-treated myocardial infarct rats. Binding studies of Ang II on endothelial cell lining and directly on myocytes in sham-operated and infarcted perfused rat hearts revealed that, in myocardial infarcted-animals, Ang II binding affinity increased both in the endothelium and in myofibres. This may be considered a major putative effect of the peptide in potentiating the pharmacodynamics of hypertrophy. In losartan-treated myocardial infarcted-animals, a marked increase in the binding affinities of Ang II for the AT2-receptor subtype was observed. Hence, potential cardioprotective effects of the AT 1-receptor antagonist are proposed.