bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative backscattered electron imaging of bone in proximal femur fragility fracture and medical illness
Authors: SUTTON‐SMITH P. , BEARD H. , FAZZALARI N. 
Published: February 2008

SummaryBone quality consists of a number of factors including the amount of bone, bone architecture and the degree of bone mineralization. Quantitative backscattered electron imaging is a technique that allows the degree of mineralization of trabeculae to be assessed and in this study is applied to inter‐trochanteric bone biopsies of the proximal femur.Biopsy cores from 22 controls, nine individuals with acute and chronic medical conditions and 22 fragility fracture individuals undergoing total hip replacement were processed into methyl methacrylate, polished and analysed in a Philips XL20 scanning electron microscope. A mean and distribution of weight percent calcium were determined for each individual, and for the control, medically ill and fragility fracture groups.All individuals and groups of individuals showed normal distributions of percent calcium with both the ill and fragility fracture groups being under mineralized relative to the control group. The shape and position of the mineralization distributions suggest that the fragility group resulted from increased bone turnover with a slow progression to under mineralization. In contrast, the ill group appears to have had a more rapid change in the mineralization dynamic.Clear distinctions between the control, fragility fracture and medically ill groups could be seen when the mineralization data were plotted as a scatter graph against age.Graphing the data in this way showed an age‐related increase in the degree of mineralization in control individuals with the under‐mineralized, fragility fracture group scattered below this normal trend. The medically ill group was similarly less mineralized which highlighted the degree to which medical conditions and treatments can alter bone matrix mineralization.
Imaging with neutral atoms—a new matter‐wave microscope
Authors: KOCH M. , REHBEIN S. , SCHMAHL G. , REISINGER T. , BRACCO G. , ERNST W. E. , HOLST B. 
Published: February 2008

SummaryMatter‐wave microscopy can be dated back to 1932 when Max Knoll and Ernst Ruska published the first image obtained with a beam of focussed electrons. In this paper a new step in the development of matter‐wave microscopy is presented. We have created an instrument where a focussed beam of neutral, ground‐state atoms (helium) is used to image a sample. We present the first 2D images obtained using this new technique. The imaged sample is a free‐standing hexagonal copper grating (with a period of about 36 μm and rod thickness of about 8 μm). The images were obtained in transmission mode by scanning the focussed beam, which had a minimum spot size of about 2.0 μm in diameter (full width at half maximum) across the sample. The smallest focus achieved was 1.9 ± 0.1 μm. The resolution for this experiment was limited by the speed ratio of the atomic beam through the chromatic aberrations of the zone plate that was used to focus. Ultimately the theoretical resolution limit is set by the wavelength of the probing particle. In praxis, the resolution is limited by the source and the focussing optics.
Wetting behaviour during evaporation and condensation of water microdroplets on superhydrophobic patterned surfaces
Authors: JUNG Y. C. , BHUSHAN B. 
Published: February 2008

SummarySuperhydrophobic surfaces have considerable technological potential for various applications due to their extreme water repellent properties. The superhydrophobic surfaces may be generated by the use of hydrophobic coating, roughness and air pockets between solid and liquid. The geometric effects and dynamic effects, such as surface waves, can destroy the composite solid–air–liquid interface. The relationship between the water droplet size and geometric parameters governs the creation of composite interface and affects transition from solid–liquid interface to composite interface. Therefore, it is necessary to study the effect of droplets of various sizes. We have studied the effect of droplet size on contact angle by evaporation using droplets with radii ranging from about 300 to 700 μm. Experimental and theoretical studies of the wetting properties of silicon surfaces patterned with pillars of two different diameters and heights with varying pitch values are presented. We propose a criterion where the transition from Cassie and Baxter regime to Wenzel regime occurs when the droop of the droplet sinking between two asperities is larger than the depth of the cavity. The trends are explained based on the experimental data and the proposed transition criteria. An environmental scanning electron microscopy (ESEM) is used to form smaller droplets of about 20 μm radius and measure the contact angle on the patterned surfaces. The investigation has shown that ESEM provides a new approach to wetting studies on the microscale.
In vivo imaging of cellular structures in Caenorhabditis elegans by combined TPEF, SHG and THG microscopy
Authors: GUALDA E. J. , FILIPPIDIS G. , VOGLIS G. , MARI M. , FOTAKIS C. , TAVERNARAKIS N. 
Published: February 2008

SummaryIn this study, we use combined two‐photon excitation fluorescence (TPEF), second‐harmonic generation (SHG) and third‐harmonic generation (THG) measurements to image cellular structures of the nematode Caenorhabditis elegans, in vivo. To our knowledge, this is the first time that a THG modality is employed to image live C. elegans specimens. Femtosecond laser pulses (1028 nm) were utilized for excitation. Detailed and specific structural and anatomical features can be visualized, by recording THG signals. Thus, the combination of three image‐contrast modes (TPEF‐SHG‐THG) in a single instrument has the potential to provide unique and complementary information about the structure and function of tissues and individual cells of live biological specimens.
Oolong tea extract as a substitute for uranyl acetate in staining of ultrathin sections
Authors: SATO S. , ADACHI A. , SASAKI Y. , GHAZIZADEH M. 
Published: February 2008

SummaryIn conventional transmission electron microscopy, uranyl acetate staining is used to enhance the cellular components. However, uranyl acetate is considered a radioactive material that is very toxic  if  ingested or inhaled and subject to restrictions in many countries. In an attempt to introduce a substitute for uranyl acetate, we evaluated oolong tea extract (OTE) for staining of ultrathin sections. Tissue sections from normal rat liver representing an ideal model organ were processed according to a routine electron microscopic fixation and embedding procedure. Serial ultrathin sections were cut and processed with either routine double electron staining or 0.2% OTE staining for 30–40 min at room temperature followed by lead citrate staining (OTE staining method). Transmission electron microscopy observations revealed that all sub‐cellular structures in hepatocytes were clearly visible with OTE staining and the quality of staining was highly compatible with those of routine double staining methods. It is suggested that OTE could be used as a non‐radioactive and hazard‐free substitute for uranyl acetate in transmission electron microscopy staining.
Crucial role of cytosolic tryparedoxin peroxidase in Leishmania donovani survival, drug response and virulence
Authors: Iyer Jitesh P. , Kaprakkaden Anees , Choudhary Manohar L. , Shaha Chandrima 
Published: February 2008

Summary Leishmania donovani, the causative agent of visceral leishmaniasis, uses a cascade of enzymes that include cytosolic tryparedoxin peroxidase (cTXNPx) for detoxification of peroxides, an event pivotal for survival of digenic parasites living in two disparate biological environments. In this study, we observed an increase in promastigote cTXNPx levels after exposure to H2O2 and this group did not show any cell death; however, exposure to a combination of H2O2 and nitric oxide resulted in significant reduction of cTXNPx levels accompanied by high cell death. The protective relationship between higher levels of cTXNPx and survival was further substantiated by the improved ability of L. donovani promastigotes overexpressing cTXNPx to withstand exposure to H2O2 and nitric oxide combination as compared with vector transfectants. In addition, cTXNPx transfectants demonstrated increased virulence, causing higher parasite burden in macrophages as compared with vector transfectants. Interestingly, the cTXNPx transfectants as promastigotes or amastigotes were resistant to clearance by the anti‐leishmanial drug antimony, suggesting a cTXNPx link to drug response. Mechanistically, cTXNPx overexpression was protective against changes in Ca2+ homeostasis but not against mitochondrial hyperpolarization brought about by exposure to H2O2 and nitric oxide. Therefore, this study provides a link between cTXNPx expression to survival, virulence and drug response in L. donovani.
Quercitol and osmotic adaptation of field‐grown Eucalyptus under seasonal drought stress
Authors: ARNDT STEFAN K. , LIVESLEY STEPHEN J. , MERCHANT ANDREW , BLEBY TIMOTHY M. , GRIERSON PAULINE F. 
Published: February 2008

ABSTRACTThis study investigated the role of quercitol in osmotic adjustment in field‐grown Eucalyptus astringens Maiden subject to seasonal drought stress over the course of 1 year. The trees grew in a native woodland and a farm plantation in the semi‐arid wheatbelt region of south Western Australia. Plantation trees allocated relatively more biomass to leaves than woodland trees, but they suffered greater drought stress over summer, as indicated by lower water potentials, CO2 assimilation rates and stomatal conductances. In contrast, woodland trees had relatively fewer leaves and suffered less drought stress. Plantation trees under drought stress engaged in osmotic adjustment, but woodland trees did not. Quercitol made a significant contribution to osmotic adjustment in drought‐stressed trees (25% of total solutes), and substantially more quercitol was measured in the leaves of plantation trees (5% dry matter) than in the leaves of woodland trees (2% dry matter). We found no evidence that quercitol was used as a carbon storage compound while starch reserves were depleted under drought stress. Differences in stomatal conductance, biomass allocation and quercitol production clearly indicate that E. astringens is both morphologically and physiologically ‘plastic’ in response to growth environment, and that osmotic adjustment is only one part of a complex strategy employed by this species to tolerate drought.
Klebsormidium flaccidum, a charophycean green alga, exhibits cold acclimation that is closely associated with compatible solute accumulation and ultrastructural changes
Authors: NAGAO MANABU , MATSUI KENJI , UEMURA MATSUO 
Published: February 2008

ABSTRACTTo elucidate the fundamental mechanisms and subsequent evolutionary aspects of plant cold acclimation, we examined the effect of cold acclimation on freezing tolerance in Klebsormidium flaccidum, a green alga belonging to Charophyceae, a sister group of land plants. Freezing tolerance of K. flaccidum was significantly enhanced by cold treatment: survival increased from 15% at −10 °C when grown at 18 °C to 55 and 85% after exposure at 2 °C for 2 and 7 d, respectively. Accompanying the development of freezing tolerance, soluble sugars (glucose and sucrose), a putative glycoside and amino acids, including γ‐aminobutyric acid (GABA), accumulated to high levels in the alga, suggesting that these solutes play a crucial role in the cold acclimation of K. flaccidum. Interestingly, the application of abscisic acid (ABA) did not change the freezing tolerance of the alga. We also observed changes in cell structure, including increased numbers and sizes of starch grains in chloroplasts, chloroplast enlargement, vacuole size reduction and cytoplasmic volume increase. These results suggest that K. flaccidum responds well to cold treatment and develops freezing tolerance in a process comparable to that of land plants.
Pulmonary complaints and lung function after pediatric kidney transplantation
Authors: Cransberg Karlien , Pijnenburg Mariëlle , Lunstroot Maaike , Lilien Marc , Cornelissen Elisabeth , Davin Jean Claude , VanHoeck Koen , Merkus Peter , Nauta Jeroen 
Published: February 2008

Abstract: Recently four of 38 children with a kidney transplant were diagnosed with bronchiectasis. The aim of the current study was to identify patients with increased risk for pulmonary damage. In this cross‐sectional observational study, children with a functioning kidney graft in the Netherlands and Antwerp, Belgium, were screened with the use of a symptom checklist and spirometry. Maximum score for upper airway complaints was 21 (normal: <8), for lower airway complaints 28 (<10). Results of FVC, FEV1 and MEF25 were expressed as percentage predicted for height and sex. One hundred and thirty‐five patients completed the interview (122) and/or spirometry (103); 91 did both. Lower airways symptoms were above acceptable levels in 18 (14%) patients. Forty‐nine patients (48%) had an abnormal lung function test: in 12 concerning FVC%, in 11 FEV1%, in 24 MEF25% and in 36 FEV1/FVC. Of correlations between symptomatology or spirometry data, and clinical parameters, only that between GFR and MEF25% was statistically significant. Children with a kidney transplant are at increased risk for obstructive lung disease. We recommend to monitor lung function during the follow‐up after renal transplantation.
The use of Doppler tissue imaging to predict cellular and antibody‐mediated rejection in pediatric heart transplant recipients
Authors: Behera Sarina K. , Trang Janet , Feeley Brian T. , Levi Daniel S. , Alejos Juan C. , Drant Stacey 
Published: February 2008

Abstract: DTI indices have been associated with cellular rejection in adult heart transplant recipients, but their predictive value in pediatric recipients is unknown. The purpose of this study was to evaluate DTI measures in the detection of cellular and AMR in pediatric heart transplant recipients. One hundred and forty‐eight pediatric heart transplant recipients who had 267 cardiac catheterization procedures with EMB, echocardiogram with DTI, and BNP level performed on the same day were included in the study. For the mitral and tricuspid valves, the ratios (E/E’) between the early diastolic inflow velocity by pulsed Doppler (E, m/s) and the early diastolic annular velocity by DTI (E’, m/s) were obtained and compared between subjects with and without rejection. Of the 148 recipients, 30 subjects had a total of 37 episodes of rejection: 10 cellular (≥1B), 17 AMR, and 10 biopsy‐negative clinical rejection. Mitral and tricuspid valve E/E’ ratios were significantly higher in rejectors than in non‐rejectors (5.5 ± 1.3 vs. 4.4 ± 1.4, p < 0.001 and 4.9 ± 2.1 vs. 4.1 ± 1.5, p < 0.01, respectively). By multivariate linear regression, mitral valve E/E’ was an independent predictor of rejection. Mitral and tricuspid valve E/E’ <5.0 had 93% and 89% NPV, respectively, for rejection. Mitral and tricuspid valve E/E’ ratios <5.0 may be useful non‐invasive screening measures to exclude rejection in pediatric heart transplant recipients.
CAN WE LIVE WITHOUT A FUNCTIONAL RENIN‐ANGIOTENSIN SYSTEM?
Authors: Pierre Corvol , Annie Michaud , Olivier Gribouval , Jean‐Marie Gasc , Marie‐Claire Gubler 
Published: February 2008

SUMMARY

In mice, inactivation of any of the components of the renin‐angiotensin system (i.e. renin, angiotensin‐converting enzyme, angiotensinogen and AT1 receptor) is dispensable for survival at birth. Animals can survive although they are more sensitive to salt depletion than the wild type mice.
Renal tubular dysgenesis (RTD) is a human disease consisting of severe abnormalities of renal tubular development and resulting in profound anuria and perinatal death.
Familial RTD is an autosomal recessive disease due to genetic defects in any of the constituents of the renin system.
Complete gene inactivation of the renin system in RTD leads to neonatal anuria and death. Proximal tubules are almost absent; renal artery hyperplasia is found in all cases of RTD. An intense stimulation of renin gene expression is noted in the kidney of patients with mutations affecting angiotensinogen, angiotensin‐converting enzyme and AT1 receptor.
The more severe phenotype in humans than in mice devoid of a functional renin system may be attributable to the difference in nephrogenesis between mice and humans. In mice, nephrogenesis is completed 2 weeks after birth, whereas in humans it is completed before birth, at 38 weeks of gestation.
REACTIVE OXYGEN SPECIES AND GLUCOCORTICOID‐INDUCED HYPERTENSION
Authors: Ong Sharon LH , Zhang Yi , Whitworth Judith A 
Published: February 2008

SUMMARY

There is increasing evidence for a role of oxidative stress and nitric oxide deficiency in experimental glucocorticoid‐induced hypertension, as evidenced by increased biomarkers of oxidative stress; the effectiveness of antioxidants or reduced NADPH oxidase antagonists in lowering blood pressure; and secondary upregulation of endogenous antioxidant enzymes in response to oxidative stress.
In the vasculature, the main sources of superoxide are NADPH oxidase, xanthine oxidase, uncoupled endothelial nitric oxide synthase (eNOS) and mitochondria.
NADPH oxidase plays a significant role in the pathogenesis of glucocorticoid‐induced hypertension in the rats, but xanthine oxidase and uncoupled eNOS pathways are not important sources of reactive oxygen species in these models. The role of mitochondrial reactive oxygen species in glucocorticoid‐induced hypertension remains to be clarified.
CARDIOVASCULAR AND METABOLIC EFFECTS OF OBESITY
Authors: Morris Margaret J 
Published: February 2008

SUMMARY

Obesity is an important risk factor for hypertension and its incidence is increasing around the world.
The mechanisms underlying obesity‐related hypertension include sympathetic activation, altered vascular responses, hormonal changes, enhanced inflammatory markers and structural changes.
This review summarizes recent evidence of the underlying impact of obesity on blood pressure. A number of candidate mechanisms include increased sympathetic activity, activation of the renin‐angiotensin system, altered vasoconstrictor or dilator responses and the attendant systemic inflammatory state.
While adult lifestyle factors undoubtedly contribute to the incidence of obesity and its attendant hypertension, evidence suggests that the programming of obesity may occur following over‐nutrition during development. A growing body of evidence links maternal obesity, offspring obesity and hypertension.
Finally, epigenetic modification of genes relevant to hypertension may contribute to the development of hypertension following a suboptimal intrauterine environment. To date the cardiovascular effects of early nutritional changes have been largely investigated following maternal under‐nutrition or protein restriction; further work is necessary to determine the impact of maternal obesity.
Improving detection and quality of assessment of child abuse and partner abuse is achievable with a formal organisational change approach
Authors: Wills Russell , Ritchie Miranda , Wilson Mollie 
Published: February 2008

Aim:  To improve detection and quality of assessment of child and partner abuse within a health service.Methods:  A formal organisational change approach was used to implement the New Zealand Family Violence Intervention Guidelines in a mid‐sized regional health service. The approach includes obtaining senior management support, community collaboration, developing resources to support practice, research, evaluation and training. Formal pre–post evaluations were conducted of the training. Barriers and enablers of practice change were assessed through 85 interviews with 60 staff. More than 6000 clinical records were audited to assess rates of questioning for partner abuse. Identifications of partner abuse and referrals made were counted through the Family Violence Accessory File. Referrals to the Department of Child, Youth and Family Services (CYFS) were recorded routinely by the CYFS. Audits assessed quality of assessment of child and partner abuse, when identified.Results:  More than 700 staff were trained in dual assessment for child and partner abuse. Evaluations demonstrate improved confidence following training, though staff still need support. Barriers and enablers to asking about partner abuse were identified. Referrals from the health service to the CYFS increased from 10 per quarter to 70 per quarter. Identification of partner abuse increased from 30 to 80 per 6‐month period. Routine questioning rates for partner abuse vary between services.Conclusion:  Achieving and sustaining improved rates of identification and quality of assessment of child and partner abuse is possible with a formal organisational change approach.
Seed longevity of eight species common during early postfire regeneration in south‐eastern Spain: A 3‐year burial experiment
Authors: BUHK CONSTANZE , HENSEN ISABELL 
Published: February 2008

AbstractSpecies that frequently regenerate sexually after fire were not found in soil seed banks of previous studies in south‐eastern Spain (Province of Murcia) and this led to the idea of studying seed longevity in the species concerned. A seed burial field experiment was carried out over a period of 30 months to examine the seed longevity of eight species that mainly reproduce sexually during early postfire succession. In addition, longevity was determined for seeds stored at room temperature and the results were compared to those obtained for buried seeds. Seeds of the study species showed very different patterns of persistence. Water‐impermeable seeds of Cistus albidus, Cistus clusii, Fumana laevipes, Convolvulus lanuginosus and Calicotome intermedia survived at least 1 year of burial in high numbers. However, seeds of Calicotome intermedia did not survive a second year, and only approximately 20% of the Fumana laevipes and Convolvulus lanuginosus seeds were alive after 30 months of burial. The longevity of buried water‐permeable seeds of Asterolinum linum‐stellatum, Teucrium pseudochamaepitys and Stipa tenacissima did not exceed 2 years. When buried for 30 months in a coastal and a mountain population site, the number of viable seeds of Convolvulus lanuginosus and Stipa tenacissima did not differ significantly between the two sites. Seeds of most species showed better survival under room temperature than under burial conditions. We concluded that the seed longevity of some species in soil might have previously been overestimated.
The concept of neurogenic inflammation
Authors: Geppetti Pierangelo , Nassini Romina , Materazzi Serena , Benemei Silvia 
Published: February 2008

Neurogenic inflammatory responses have recently been linked to both acute and chronic pathological conditions in the urinary tract. Neurogenic inflammation encompasses a series of vascular and non‐vascular inflammatory responses, triggered by the activation of primary sensory neurons and the subsequent release of inflammatory neuropeptides, including substance P and calcitonin gene‐related peptide. The reduction of neurogenic inflammatory responses may be key in the mode of action of the adrenergic α1‐adrenoceptor antagonists used to treat lower urinary tract symptoms (LUTS). Indeed, the α1‐adrenoceptor antagonist alfuzosin inhibits expression of the oncogene c‐fos– a marker of nociceptive pathway activation – evoked by cyclophosphamide in rats.Capsaicin ameliorates urinary bladder symptoms through its stimulatory action on the transient receptor potential vanilloid 1 (TRPV1) calcium channel, resulting in desensitization of bladder sensory nerve terminals. Involvement of the TRP cation channel, subfamily A, member 1 (TRPA1) has also been reported in models of neurogenic inflammation and nociception promoted by the cyclophosphamide metabolite, acrolein. Blockade by alfuzosin demonstrates the beneficial effects of α1‐adrenoceptor antagonists on neurogenic inflammation via the transient receptor potential family of ionic channels. Consequently, these drugs may have an important role in reducing LUTS.