bluuebunny/crossref_metadata_2025 huggingface dataset:
Neuropsychological function in Greek patients with chronic hepatitis C
Authors: Karaivazoglou Katerina , Assimakopoulos Konstantinos , Thomopoulos Konstantinos , Theocharis George , Messinis Lambros , Sakellaropoulos George , Labropoulou‐Karatza Chryssoula
Published: May 2007

Background: Research has shown that hepatitis C virus (HCV) infection is associated with subclinical neuropsychological deficits in the absence of hepatic encephalopathy.

Methods: The current study assessed 32 Greek HCV patients without hepatic encephalopathy using standardized neuropsychological measures and compared them with 20 healthy controls and 29 hepatitis B virus (HBV)‐infected patients. Patients and controls did not differ on age, educational level, depression or fatigue severity. Moreover, strict criteria were used to exclude any risk factor for cognitive impairment.

Results: Chronic HCV patients performed significantly worse than healthy controls on verbal learning and memory (P=0.029). However, hepatitis C and hepatitis B patients were similarly impaired in cognitive function, suggesting that the observed abnormalities are not HCV specific. HCV patients' cognitive capacity was further associated with liver disease severity as indicated by fibrosis stage (r=−0.602, P=0.011). In contrast, cognitive decline did not correlate with patients' psychological distress, indicating that biological mechanisms might be implicated in its pathogenesis. Finally, after controlling for age and educational level, cirrhotic and non‐cirrhotic patients appeared to be equally impaired.

Conclusions: In conclusion, this study confirmed previous findings and added further to the existing literature concerning the negative influence of HCV infection on cognition.
Evaluation of hepatic steatosis by ultrasound in patients with chronic hepatitis C virus infection
Authors: Hirche T. O. , Ignee A. , Hirche H. , Schneider A. , Dietrich C. F.
Published: May 2007

Objective: To compare two alternative ultrasound parameters, hepatic vein flow (HVF) pattern and presence of focal hypoechoic areas (FHA) within the liver hilus, as non‐invasive predictors of liver steatosis in patients with chronic hepatitis C virus (HCV) infection.

Design: In 122 consecutive patients with chronic HCV infection, the HVF pattern and presence of FHA within the liver hilus were assessed by Duplex–Doppler and B‐mode sonography. All patients underwent liver biopsy and the sonographic results were compared with a histological score of steatosis used as the gold standard for this purpose. Association of fatty infiltrations with clinical and sonographic features were evaluated by a stepwise logistic regression analysis.

Results: Reduced HVF and FHA, but not standard clinical and laboratory parameters, strongly correlated with steatosis on histology (P<0.001). Both sonographic parameters made excellent predictions for the subgroup of patients with severe steatosis, particularly when both tests were combined [sensitivity (SE) 95%, specificity (SP) 96%, positive predictive value (pPV) 93%, negative predictive value (nPV) 97%, and accuracy 96%]. However, the sensitivity and accuracy of HVF pattern analysis were markedly reduced when all degrees of steatosis were defined as positive (SE 71%, SP 76%, pPV 81%, nPV 64%, and accuracy 73%). In contrast, the dichotomous parameter FHA remained a powerful indicator even under the latter conditions (SE 74%, SP 100%, pPV 100%, nPV 72%, and accuracy 84%). The combination of both sonographic tests resulted in improved sensitivity (82%), but significant loss of specificity (76%) and accuracy (80%) for prediction of liver steatosis.

Conclusion: Sonographic evaluation of reduced HVF and FHA within the liver hilum is easy to perform, non‐invasive, and, when present, gives a high degree of confidence in the diagnosis of liver steatosis. However, the lack of sonographic evidence of steatosis cannot definitively exclude the presence of mild steatosis, as shown on biopsy.
Stronger Neo‐Minophagen C™, a glycyrrhizin‐containing preparation, protects liver against carbon tetrachloride‐induced oxidative stress in transgenic mice expressing the hepatitis C virus polyprotein
Authors: Hidaka Isao , Hino Keisuke , Korenaga Masaaki , Gondo Toshikazu , Nishina Sohji , Ando Miye , Okuda Michiari , Sakaida Isao
Published: May 2007

Background/Aim: Stronger Neo‐Minophagen C™ (SNMC), a glycyrrhizin‐containing preparation, has been used as a treatment for chronic hepatitis for more than 30 years in Japan, and shown to be effective in preventing the development of hepatocellular carcinoma in chronic hepatitis C patients, but its underlying mechanisms remain elusive. The aim of this study was to investigate if SNMC had an anti‐oxidative effect, as oxidative stress has been proposed to be one of the mechanisms of liver injury in hepatitis C virus (HCV)‐associated chronic liver diseases.

Methods: The protective effect of SNMC against carbon tetrachloride (CCl4)‐induced liver injury was examined using transgenic mice expressing the HCV polyprotein.

Results: A small dose of CCl4 (10 μl/kg of body weight) significantly increased the serum alanine aminotransferase (ALT) level and hepatic malondialdehyde content, decreased hepatic reduced glutathione (GSH) content and induced ultrastructural alterations of hepatic mitochondria in transgenic mice, but not in nontransgenic mice. A single SNMC treatment equivalent to a clinical dose significantly restored the serum ALT level and hepatic malondialdehyde and GSH contents, attenuated the ultrastructural alterations of hepatic mitochondria, and increased mRNA expression of γ‐glutamylcysteine synthetase (γ‐GCS).

Conclusions: Transgenic mice expressing the HCV polyprotein are abnormally vulnerable to oxidative stress. SNMC protects hepatocytes against CCl4‐induced oxidative stress and mitochondrial injury in the presence of HCV proteins by restoring depleted cellular GSH.
Severe portal hypertension secondary to arterio‐portal fistula: salvage surgical treatment
Authors: Dumortier Jérôme , Pilleul Frank , Adham Mustapha , Vochelle Véronique , Hervieu Valérie , Bouffard Yves , Valette Pierre‐Jean , Scoazec Jean‐Yves , Boillot Olivier
Published: May 2007

Background: Arterio‐portal fistulas (APFs) are rare vascular disorders of various origins that can lead to severe portal hypertension. Even if surgery was initially the treatment of choice, more recently, interventional radiological procedures have been considered as the first line therapeutic option.

Case Report: A man with no history of liver disease was admitted for abdominal pain and distension. Abdominal ultrasonography with Doppler, magnetic resonance imaging and computed tomography (CT) scan showed ascites, splenomegaly and a probable APF between the left branches of both the hepatic artery and portal vein, associated with hepatofugal portal flow. Upper gastrointestinal endoscopy revealed large oesophageal varices without bleeding. A celiac and mesenteric arteriography and a splenic arteriography were performed and confirmed the existence of multiple intrahepatic APFs. The initial treatment consisted of two sessions of percutaneous transcatheter endovascular embolization. Unfortunately, ascites worsened, and the patient did not respond to diuretic treatment. Therefore, a surgical treatment was considered to be the only suitable treatment because of the absence of improvement after embolization procedures. A left hepatectomy with hepatic artery ligation was performed. Clinical evolution was favourable; an improvement of ascites was obtained; control ultrasonography and CT scan disclosed no residual haemodynamic abnormality; and the portal vein was normal with a hepatopedal flow. Currently, 12 months after surgery, the clinical condition of the patient is good.

Conclusion: Percutaneous treatment of portal hypertension by embolizing multiple large APF has been described to be an effective method. Nevertheless, failure of such conservative treatment is possible and must lead to a salvage surgery.
Risk factors for human immunodeficiency virus infection among blood donors in Sao Paulo, Brazil, and their relevance to current donor deferral criteria
Authors: De Almeida Neto Cesar , McFarland William , Murphy Edward L. , Chen Sanny , Nogueira Fatima Aparecida Hangai , Mendrone Alfredo , Salles Nanci Alves , Chamone Dalton Alencar Fischer , Sabino Ester Cerdeira
Published: May 2007

BACKGROUND: The objective of this study was to investigate risk factors of human immunodeficiency virus (HIV)‐seropositive blood donors in Brazil and to determine if current donor deferral criteria are appropriate.

STUDY DESIGN AND METHODS: Demographic and behavioral data among cases with confirmed HIV seropositivity (n = 272) were compared with those who had a false‐positive serology (n = 468) between January 1999 and December 2003 in a case‐control analysis with logistic regression.

RESULTS: Risk factors that should have resulted in predonation deferral were reported by 48.9 percent of HIV‐positive and 9.4 percent of false‐positive donors. In multivariate analysis, male cases were significantly more likely to report male‐male sex (adjusted odds ratio [AOR], 26.2; 95% confidence interval [CI], 7.8‐87.4), a previous sexually transmitted disease diagnosis (AOR, 3.2; 95% CI, 1.5‐6.9), exchanging money for sex (AOR, 2.1; 95% CI, 1.0‐4.2), and at least two partners in the past 12 months (AOR, 2.3; 95% CI, 1.4‐3.6). HIV‐positive male donors were also more likely to be reactive for the presence of hepatitis C virus antibody (AOR, 4.0; 95% CI, 1.3‐12.0) and hepatitis B virus core antibody (AOR, 3.8; 95% CI, 1.9‐7.7). Female cases were more likely to report an intravenous drug user partner (AOR, 12.4; 95% CI, 1.3‐120.2), a sexual partner with multiple sex partners or who had a history of sex with a sex worker (AOR, 13.0; 95% CI, 2.7‐63.2), and at least two partners in the past 12 months (AOR, 2.2; 95% CI, 1.0‐5.3).

CONCLUSION: A substantial number of HIV‐infected donors reported a risk factor that could have been identified in the predonation screening. Male‐male sexual behavior was still the strongest determinant of HIV status in the studied population.
Sterility testing of hematopoietic progenitor cell products: a single‐institution series of culture‐positive rates and successful infusion of culture‐positive products
Authors: Padley Douglas J. , Dietz Allan B. , Gastineau Dennis A.
Published: May 2007

BACKGROUND: Administration of culture‐positive hematopoietic progenitor cells (HPCs) causing adverse events has been a hypothesized yet largely unmeasured risk of the clinical practice of HPC transplantation. To enhance patient safety, the FDA has issued regulations prohibiting the use of culture‐positive HPCs. Numerous studies have reported the infusion of culture‐positive HPCs; however, the low frequency of adverse events prevents accurate determination of this risk.

STUDY DESIGN AND METHODS: Product culture results and clinical outcomes from January 1998 through March 2006 representing 7233 HPC collections for 2118 transplants at a single institution were reviewed.

RESULTS: A total of 119 units of HPCs (1.6%) intended for 95 patients were culture‐positive. Of the 69 patients transplanted with culture‐positive HPCs, 5 received products with cultures pending, and 64 received products with the positive culture results known. One of 69 patients had a new positive blood culture 5 days after infusion with the same species as the product. There was not a clinically relevant difference in the rate of infusion‐related symptoms reported for patients who received culture‐positive products compared to all infusions. The survival of patients who received culture‐positive products (n = 69) was not different from all HPC recipients (n = 2046; p = 0.419).

CONCLUSION: No infusion‐related risks of culture‐positive HPCs to patient safety were identified. Our data suggest that the decision to use culture‐positive HPCs must be made in the context of the global risks associated with transplants such as remobilization, replacement product availability, and the nature of the organism.
Opinions about donating blood among those who never gave and those who stopped: a focus group assessment
Authors: Mathew Sunitha M. , King Melissa R. , Glynn Simone A. , Dietz Stephen K. , Caswell Scott L. , Schreiber George B.
Published: May 2007

BACKGROUND: Understanding what prevents people from ever donating blood, or having donated, what influenced them to stop, are both equally important in devising recruitment strategies. Enlisting new donors and encouraging previous donors to return are vital to increasing collections.

STUDY DESIGN AND METHODS: Six racially homogeneous focus groups of never donors and lapsed donors were conducted. Both sexes and a range of age groups were represented. The importance of blood donation as a volunteer activity, deterrents, motivations, awareness of need, and effective recruitment messages were topics discussed.

RESULTS: Never donors do not see blood donation as an important volunteer activity on par with others like volunteering at hospitals, schools, and support groups. Fear and inconvenience were major barriers to donating. Better education campaigns to allay fears about donating and workplace drives were considered important motivators. Participants were unaware of the need for blood. Media messages that combine safety of the process along with who it benefits were considered most effective. Messages that target the specific needs of minority communities were considered good motivators for their recruitment.

CONCLUSION: Blood collection agencies should increase awareness that blood donation is a worthwhile and important volunteer activity. Another strategy would be to capitalize on the existing perception that donating blood is like donating money or used clothing, by focusing on the concept of giving something tangible. Along with providing convenient opportunities to donate, blood centers need to effectively convey the need for blood and allay fears about the donation process to increase the current donor pool.
Bepridil Reverses Atrial Electrical Remodeling and L‐Type Calcium Channel Downregulation in a Canine Model of Persistent Atrial Tachycardia
Authors: NISHIDA KUNIHIRO , FUJIKI AKIRA , SAKAMOTO TAMOTSU , IWAMOTO JOTARO , MIZUMAKI KOICHI , HASHIMOTO NORIO , INOUE HIROSHI
Published: May 2007

Introduction: This study tested whether bepridil, a multichannel blocker, would reverse electrical remodeling induced by persistent atrial tachycardia.

Methods and Results: Fourteen dogs were subjected to rapid atrial pacing at 400 bpm for 6 weeks after atrioventricular block was created to control the ventricular rate. During the study period, seven dogs were given placebo for 6 weeks (Control group), and seven were given placebo for 3 weeks, followed by 3 weeks of bepridil (10 mg/kg/day, Bepridil group). The atrial effective refractory period (ERP) and the inducibility and duration of atrial fibrillation (AF) were determined on a weekly basis. After 6 weeks, expression of L‐type calcium channel α1C messenger ribonucleic acid (mRNA) was quantified by real‐time reverse transcription‐polymerase chain reaction. In the Control group, ERP was shortened and the inducibility and duration of AF increased through the 6‐week period. In the Bepridil group, the same changes occurred during the first 3 weeks, but were gradually reversed with bepridil. After 6 weeks, ERP was longer, AF inducibility was lower, and AF duration was shorter in Bepridil group than in the Control group. Expression of α1C mRNA was decreased by 64% in the Control group (P < 0.05 vs sham), but in the Bepridil group, it was not different compared with the sham dogs. As a whole group of dogs, ERP was positively correlated with α1C mRNA expression.

Conclusion: Bepridil reverses the electrophysiological consequences of atrial remodeling to some extent and L‐type calcium channel downregulation in a canine model of atrial tachycardia.
Habitual Cocaine Use Is Associated with High Defibrillation Threshold During ICD Implantation
Authors: CHEN JAY , NASEEM R. HARIS , OBEL OWEN , JOGLAR JOSE A.
Published: May 2007

Background:Habitual cocaine use can lead to dilated cardiomyopathy (DCM) and sudden cardiac death. Based on prior clinical observations, we hypothesized that prior habitual cocaine use is a strong predictor of high defibrillation threshold (DFT) during implantable cardioverter‐defibrillator (ICD) implant.

Methods:We reviewed the medical records of 130 consecutive patients undergoing initial ICD implantation or revision at Parkland Hospital and the Dallas VA Hospital, Dallas, TX, from January 2002 to November 2005. Patient characteristics and DFT data were collected retrospectively.

Results:The study group includes 11 patients (8.46%) who were identified as having a history of prior habitual cocaine use as demonstrated by history and urine toxicology; the rest (119 patients) form the control group. Cocaine‐using patients tended to be younger (48.2 ± 10 vs 60.1 ± 12.3 years; P = 0.0026), were less likely to have coronary disease (36.3% vs 72.2%; P = 0.032), and had less comorbidity. The average DFT was 27.9 ± 7.8 J for all cocaine‐using patients and 14.5 ± 4.1 J for noncocaine‐using patients (P = 0.00018). In the cocaine‐using group, three out of 11 patients required a subcutaneous array compared to none in the control group.

Conclusions:Our results suggest that patients with a history of habitual cocaine use may be at increased risk to have a high DFT during ICD implantation. This is the first study to demonstrate such association. ICD implantation in patients with this history should be planned with these findings in mind, as larger output generators or subcutaneous arrays might be required.
Demonstration of Left Ventricular Outflow Tract Eccentricity by Real Time 3D Echocardiography: Implications for the Determination of Aortic Valve Area
Authors: Doddamani Sanjay , Bello Ricardo , Friedman Mark A. , Banerjee Anita , Bowers James H. , Kim Bette , Vennalaganti Prashant R. , Ostfeld Robert J. , Gordon Garet M. , Malhotra Divya , Spevack Daniel M.
Published: May 2007

Background: Determination of the left ventricular outflow tract cross‐sectional area (ALVOT) is necessary for calculating aortic valve area (AVA) by echocardiography using the continuity equation (CE). In the commonly applied form of CE, πr2 is used to estimate ALVOT utilizing the assumptions that LVOT is round and the parasternal long axis (PLAX) plane bisects LVOT. Imaging LVOT using real time 3D echocardiography (RT3DE) eliminates the need for these assumptions. We tested the hypothesis that LVOT is round based on a formula for eccentricity. Methods and Results: In 53 patients, 2D echocardiography (2DE) and RT3DE were acquired. ALVOT was calculated by 2DE using πr2 (ALVOT‐2D). Using RT3DE, ALVOT planimetry was performed immediately beneath the aortic valve (ALVOT‐3Dplan). Eccentricity Index (EI) was calculated using the shortest and longest LVOT diameters. The long axis was measured to be larger by 0.53 cm ± 0.36 (P < 0.005). The median EI was 0.20 (0.00–0.54), indicating that half the subjects had at least a 20% difference between the major and minor diameters. ALVOT‐3Dplan was larger than ALVOT‐2D (3.73 ± 0.95 cm2 vs. 3.18 ± 0.73 cm2; P < 0.001) by paired analysis. Using the equation of an ellipse (πab), ALVOT‐3Dellip was 3.57 ± 0.95 resulting in improved agreement with ALVOT‐3Dplan. Conclusions: In our small patient sample with normal aortic valves, we showed the LVOT shape is usually not round and frequently, elliptical. Incorrectly assuming a round LVOT underestimated the ALVOT‐3Dplan and consequently the AVA by 15%. Investigating the LVOT in aortic stenosis is warranted to evaluate whether RT3DE may improve measurement of AVA.
Live 3D Echocardiography with the Pediatric Matrix Probe
Authors: Acar Philippe , Abadir Sylvia , Paranon Soizic , Latcu Gabriel , Grosjean Juliette , Dulac Yves
Published: May 2007

Three‐dimensional echocardiography (3DE) enables new views of heart valves and the septa to be imaged. While the previous 3DE system was cumbersome, the recent introduction of live 3DE allowed for routine use of the technique in adult patients. Here, we report our initial experiences in adapting live 3DE and the adult matrix probe to the pediatric population. Thirty‐four 3DE examinations were performed on children, aged 1 day to 12 years (n = 23; median 4 years) and fetuses 20–33 weeks in gestation (n = 11; median 25 weeks), many of whom had various congenital heart diseases. The pediatric matrix probe (2–7 MHz) was used for 2D, Doppler, and 3DE. New modalities of the Vision 2007 (Philips) were applied: live, full volume, thick slice, 3D color Doppler, the QLAB system for navigation, and cropping. The pediatric matrix probe allows for complete 2D and 3D echocardiography, and new acoustic windows are now available to perform live 3DE. The higher frequency of the probe increases the 3D image resolution obtained in neonates and fetuses. This advancement allows new views of the aorta, pulmonary valve, septa and intra cardiac anatomy to be captured. Real time 3DE is a feasible method in addition to conventional 2D echocardiography for evaluating congenital heart disease.
Gender Differences in Chronotropic and Hemodynamic Responses during Dobutamine‐Atropine Stress Echocardiography
Authors: Tsutsui Jeane Mike , Falcão Sandra Nívea Reis Saraiva , Dourado Paulo Magno Martins , Lima Marta Fernandes , Alves Angele Azevedo , Guerra Vitor Coimbra , Ramires José Antônio Franchini , Mathias Wilson
Published: May 2007

Aim: The aim of this study was to determine the influence of gender on chronotropic and hemodynamic response during dobutamine stress echocardiography with early injection of atropine (EA‐DSE).

Methods: From January 2000 to June 2003, we retrospectively evaluated patients who underwent EA‐DSE for known or suspected coronary artery disease. We studied 494 patients, 243 men and 251 women, who were not under beta‐blocker or calcium channel‐blocker therapy (Group A) and 326 patients, 157 men and 169 women, using these medications (Group B). Differences on chronotropic and hemodynamic responses during EA‐DSE were assessed by gender in the two groups. Predictors of need for higher doses of dobutamine were determined by multivariate analysis.
Results: In Group A, higher proportion of women achieved test end points at the stage of 20 mcg/kg per minute. Dobutamine and atropine doses were lower in women than in men (29 ± 5 versus 31 ± 6 mcg/kg per minute; P = 0.001 and 0.61 ± 0.32 versus 0.78 ± 0.43 mg; P = 0.006). Cardiac chronotropism and systolic blood pressure response patterns differed by gender. In Group B, there was no difference in the proportion of patients who achieved test end points at each stage of dobutamine. The independent predictors of the need for higher doses of dobutamine in Group A were gender [Odds Ratio (OR) = 1.99, 95% Confidence Interval (CI) = 1.19–3.32; P = 0.008], age (OR = 0.91,CI = 0.89–0.93; P < 0.001), and baseline heart rate (OR = 0.95,CI = 0.93–0.98; P < 0.001). Independent predictors in the total population were age (OR = 0.92,CI = 0.90–0.94; P < 0.001), baseline heart rate (OR = 0.95,CI = 0.93–0.97; P < 0.001), and beta‐blocker therapy (OR = 0.42,CI = 0.18–1.51; P = 0.04).
Conclusion: Gender has influence on heart rate and blood pressure response to the EA‐DSE in patients without use of drugs with negative chronotropic effects.
Adsorption of human plasma proteins to modified titanium surfaces
Authors: Sela Michael N. , Badihi Liad , Rosen Graciela , Steinberg Doron , Kohavi David
Published: May 2007

Objectives: The aim of this study was to examine the effect of modified titanium (Ti) surfaces on the initial events of plasma proteins adsorption.

Materials and methods: ‘Ti disks’ with three types of surface modifications were compared: machined, acid‐etched and acid‐etched and blasted. Physical and chemical characterizations of the surfaces were performed via scanning electron microscopy (SEM), atomic force microscopy (AFM) used for analysis of surface topography, characterization of the titanium oxide (TiO2) layer was carried out by X‐ray photoelectron spectroscopy (XPS) and characterization of surface energy by the determination of contact angles. Evaluation of plasma proteins' adsorption to the treated Ti surfaces was performed by mass spectrometry, confocal laser scanning microscopy and XPS. Quantitative proteins' assessment was carried out by enzyme‐linked immunosorbent assay.

Results: SEM images revealed major differences in the topography of the examined surfaces. Acid‐etched and blasted Ti surfaces were found to have higher roughness values and a thicker TiO2 layer as compared with acid‐etched and machined surfaces. Moreover, acid‐etched and blasted surfaces showed high surface area differentiation, pointing to a high increase in the three‐dimensional (3D) surface area over the 2D surface area compared with the other surfaces. Adsorption of plasma proteins to the acid‐etched and blasted Ti surfaces was both qualitatively and quantitatively more intense compared with the machined and acid‐etched surfaces. This was shown for each examined protein, total proteins and by the removal degree of the protein coat.

Conclusions: The preferential adsorption of plasma proteins to the acid‐etched and blasted Ti surfaces may be explained by its topographical characteristics and by the increase of the 3D surface area of this modified surface.
Innate immune responses of gingival epithelial cells to nonperiodontopathic and periodontopathic bacteria
Authors: Ji S. , Kim Y. , Min B.‐M. , Han S. H. , Choi Y.
Published: May 2007

Background and Objective:  We have previously reported different susceptibilities of periodontopathic and nonperiodontopathic bacteria to antimicrobial peptides and phagocytosis by neutrophils. Differences between the two groups of bacteria may exist also in their ability to induce immune responses from the host. Therefore, we evaluated the effects of various oral bacteria on innate immune responses by gingival epithelial cells.

Material and Methods:  HOK‐16B cells were cocultured with live or lysed nonperiodontopathic (n = 3) and periodontopathic (n = 5) bacterial species. The levels of human beta defensin‐1, ‐2 and ‐3, and of the cathelicidin, LL‐37, were examined by real‐time reverse transcription‐polymerase chain reaction, and the accumulated interleukin‐8 and interleukin‐1α were measured by enzyme‐linked immunosorbent assay.

Results:  Nonperiodontopathic bacteria up‐regulated some antimicrobial peptides without affecting the levels of cytokines. In the periodontopathic group, the orange‐complex bacteria induced antimicrobial peptides and interleukin‐8 efficiently, but the red‐complex bacteria often demonstrated suppressive effects. In contrast to live bacteria, bacterial lysates had no suppressive effects. In addition, some bacterial lysates demonstrated a reduced ability to induce antimicrobial peptides compared with live bacteria.

Conclusion:  The nonperiodontopathic, the orange‐complex, and the red‐complex bacteria had different effects on the innate immune responses from gingival epithelial cells, which may affect the outcome of their host–microbial interaction in gingival sulcus.
Gingival inflammation, increased periodontal pocket depth and elevated interleukin‐6 in gingival crevicular fluid of depressed women on long‐term sick leave
Authors: Johannsen A. , Rydmark I. , Söder B. , Åsberg M.
Published: May 2007

Background and Objective:  The aim of this work was to investigate periodontal status, in relation to inflammatory markers and cortisol, in the gingival crevicular fluid and saliva of a homogenous group of women on long‐term sick leave for job‐stress related depression in comparison to nondepressed women.

Material and Methods:  The participants comprised 20 women with depression (DSM‐IV) (mean age 48.5 ± 6.9 years) and 29 healthy controls (mean age 54.5 ± 2.9 years). Clinical examination was performed. Gingival crevicular fluid was collected by an intracrevicular washing technique. Interleukin‐1β, interleukin‐6, matrix metalloproteinase (MMP)‐8 and MMP‐9 were determined with enzyme‐linked immunosorbent assay and cortisol was determined by using a radioimmunoassay. One‐way analysis of covariance was used as the statistical method.

Results:  The depressed patients had significantly higher gingival inflammation (p < 0.001), and deeper pockets (p < 0.003), than the healthy controls, after adjusting for age and smoking. The levels of interleukin‐6 in the gingival crevicular fluid were significantly higher in the patients than in the controls: 3.84 ± 1.58 pg per site and 0.79 ± 1.83 pg per site, respectively, p < 0.003. There were no significant differences in the levels of interleukin‐1β, MMP‐8 and MMP‐9. The patients had lower cortisol values in gingival crevicular fluid than the controls, whereas the levels of cortisol in saliva were similar in both groups.

Conclusion:  Women on long‐term sick‐leave for depression had more severe periodontitis and higher concentrations of interleukin‐6 in gingival crevicular fluid than healthy controls. An alteration of the immune system in these patients might be interpreted as reflecting the consequences of long‐term stress exposure and might contribute to worse periodontal conditions in these particular patients.
Strain in the nail at fingertip compression
Authors: Sakai Naotaka , Shimawaki Satoshi
Published: May 2007

Purpose: Distribution of nail strain due to compressive force in the finger pulp was investigated.

Methods: Nail strain of the right index finger of 10 healthy men was measured using three strain gauges with two axes. Each nail strain was measured along the longitudinal and the transverse axis using sensor interface. Three CCD cameras recorded the compressive force and the fingertip deformation. Each subject pressed the right index finger with 30°, 45° and 60° in the contact angle, with the compressive force increased from 0 to 14 N.

Results: When the contact angle was 30°, the strain along the transverse axis increased according to the compressive force increased. The proximal‐radial‐transverse strain at compressive force of 13 N was significantly (P<0.01) larger than the proximal‐ulnar‐transverse strain. At the same compressive force, the distal‐central‐transverse strain was significantly (P<0.05) larger than the proximal‐ulnar‐transverse strain. The proximal‐radial‐transverse strain was significantly (P<0.01) larger than the proximal‐radial‐longitudinal strain. In the contact angle of 45° and 60°, same results were gained.

Conclusion: Nail strain due to compressive force in the finger pulp was different between the rectangular axes, between the distal and the proximal parts of the nail, and between the radial and the ulnar sides.
Does Species Range and Rarity Affect Population Genetics? A Case Study of FourGraptophyllumSpecies from Queensland, Australia
Authors: Shapcott Alison
Published: May 2007

There are four species ofGraptophyllum(Acanthaceae) in Australia which span a gradient in rarity and conservation status from the most endangered,Graptophyllum reticulatum(endangered), toG. ilicifolium(vulnerable), toG. excelsum(rare), to the least endangeredG. spinigerum(widespread).Graptophyllum reticulatumandG. ilicifoliumare each only known from three locations. All species were found to have quite high levels of genetic diversity (He, A, Ap, P) and there was no significant difference among species in genetic diversity (P> 0.05), thus, genetic diversity was unrelated to conservation status or species geographic range. All species had high allelic fixation values (F ), indicating that populations were effectively inbred regardless of conservation status and geographic range. The genetic diversity among populations (FST) was not related to rarity and contrasted among the most restricted species, where diversity among populations was twice as high amongG. reticulatumpopulations (FST, 0.22) compared with amongG. ilicifoliumpopulations (FST, 0.11).
Yeasts Isolated from Neotropical Wood‐Boring Beetles in SE Peru
Authors: Berkov Amy , Feinstein Julie , Small Jacinta , Nkamany Mary , Centeno Pedro
Published: May 2007

Some temperate wood‐boring cerambycid beetles harbor intracellular gut yeasts believed to augment host nutrition, but species belonging to the subfamily Lamiinae are thought to lack endosymbionts. Almost 49 percent of Neotropical cerambycid species are lamiines, therefore, comparatively few rain forest species would be expected to host symbiotic gut yeasts. This study reports the isolation of gut yeasts from closely related Neotropical lamiines. We investigated species that feed on trees in the Brazil nut family (Lecythidaceae), because host plant associations are relatively well known. Our objectives were to determine if gut yeasts were present and, if possible, infer their mode of transmission. We collected and dissected 18 beetle specimens from three tree species, including 17 cerambycids and one curculionid. Every insect specimen yielded a gut yeast. DNA sequence libraries were used for a rapid identification of the yeasts and their larval hosts. The cerambycids included five lamiine species and one cerambycine. Six ascomycete yeasts were isolated from their guts; we found no evidence of strict vertical transmission. Larval gut yeasts were genetically similar to yeasts previously isolated from insects associated with wood or fungi, implying potential habitat specificity. The yeasts have not yet been localized, and potential function is not known, but they may contribute to rapid nutrient cycling or serve as the first line of defense against plant toxins.
Interspecific Variation in the Reproductive Response of Acacia Species to Protection from Large Mammalian Herbivores
Authors: Young Truman P. , Augustine David J.
Published: May 2007

We quantified the fruit set of four Acacia spp. inside and outside of long‐term experimental exclosures in order to examine the fitness consequences of herbivory by large mammals. We found a considerable interspecific variation in the reproductive fitness costs of herbivory in four African Acacia spp. Acacia nilotica and A. brevispica respond to protection from large mammalian herbivores by greatly increasing their seed set. In contrast, there was little or no increase in seed set in A. mellifera and A. etbaica. The reasons for these differences are not known, but may be related to armament morphologies.
Seed Dispersal of Morus macroura (Moraceae) by Two Frugivorous Bats in Xishuangbanna, SW China
Authors: Tang Zhan‐Hui , Cao Min , Sheng Lian‐Xi , Ma Xun‐Feng , Walsh Allyson , Zhang Shu‐Yi
Published: May 2007

The dispersal of Morus macroura seeds by two species of frugivorous bats (Rousettus leschenaulti and Cynopterus sphinx) was studied in a forest at Xishuangbanna Tropical Botanical Garden in Southwest China from March to May 2005. Feeding roosts were identified within 500 m around parent trees and the types and number of seed loads under each roost were recorded. We found feeding roost density decreased with increasing distance from the parent, but found no correlation between distance and seed deposition. The effect of bat digestion on seed germination was investigated, and we found that germination percentage of all treatments involving ingestion by bats was significantly lower than control seeds and some germination parameters of seeds from different treatments changed.
Controls Over Leaf Litter and Soil Nitrogen Fixation in Two Lowland Tropical Rain Forests
Authors: Reed Sasha C. , Cleveland Cory C. , Townsend Alan R.
Published: May 2007

Global comparisons suggest that rates of N fixation in tropical rain forests may be among the highest on earth. However, data supporting this contention are rare, and the factors that regulate N fixation within the biome remain largely unknown. We conducted a full‐factorial (N × P) fertilization experiment in two lowland tropical rain forests in Costa Rica to explore the effects of nutrient availability on rates of free‐living N fixation in leaf litter and soil. P fertilization significantly increased N fixation rates in both leaf litter and soil, and the effect was dependent on sampling date. Fertilization with N did not affect rates of N fixation at any time. In addition, variation in N fixation rates measured in unfertilized plots at four sampling time points suggested seasonal variability in N fixation: leaf litter N fixation ranged from 0.36 kg/ha/yr in the dry season to 5.48 kg/ha/yr in the wet season. Soil N fixation showed similar patterns ranging from a dry season low of 0.26 kg/ha/yr to a wet season high of 2.71 kg/ha/yr. While the observed temporal variability suggests potential climatic control over free‐living N fixation in these forests, data suggest that neither soil nor leaf litter moisture alone regulate N fixation rates. Instead, we hypothesize that a combination of ample C availability, low leaf litter N:P ratios, and high rainfall coincide during the latter portions of the rainy season and drive the highest free‐living N fixation rates of the year.
Rain Forest Structure at Forest‐Pasture Edges in Northeastern Costa Rica
Authors: Schedlbauer Jessica L. , Finegan Bryan , Kavanagh Kathleen L.
Published: May 2007

Land‐use change in the Sarapiquí region of Costa Rica has resulted in a fragmented forest landscape with abrupt edges between forest and pasture. Forest responses to edge effects vary widely and can significantly affect ecosystem integrity. Our objective was to examine forest structure at 20+ yr old forest‐pasture edges in Sarapiquí. Three transects with 0.095‐ha plots at seven distances from forest edges were established in each of six forest patches. Stem density, basal area, and aboveground biomass in trees and palms ≥ 10‐cm diameter at breast height were measured in all plots. In addition, hemispherical photographs were taken to determine leaf area index, understory light availability, and percent canopy openness. Linear mixed‐effects models showed significantly higher tree stem density at forest edges, relative to interiors, a pattern reflected by increased stem density, basal area, and aboveground biomass in small diameter trees (≤ 20 cm) growing near edges. No differences in total tree basal area, aboveground biomass, or hemispherical photograph‐derived parameters were detected across the forest edge to interior gradient. The recruitment of small diameter trees following edge creation has contributed to the development of dense vegetation at the forest edge and has aided in the maintenance of similar tree basal area and aboveground biomass between edge and interior environments. These data reflect on the robustness of forest edges in Sarapiquí, a characteristic that will likely minimize future detrimental edge effects and promote a number of high‐value environmental services in these forests.
Leaf Decomposition in a Dry Season Irrigation Experiment in Eastern Amazonian Forest Regrowth
Authors: Vasconcelos Steel Silva , Zarin Daniel Jacob , Da Rosa Maria Beatriz Silva , De Assis Oliveira Francisco , De Carvalho Cláudio José Reis
Published: May 2007

Leaf‐litter decomposition is a major component of carbon and nutrient dynamics in tropical forest ecosystems, and moisture availability is widely considered to be a major influence on decomposition rates. Here, we report the results of a study of leaf‐litter decomposition of five tree species in response to dry‐season irrigation in a tropical forest regrowth stand in the Brazilian Amazon; three experiments differing in the timing of installation and duration allowed for an improved resolution of irrigation effects on decomposition. We hypothesized that decomposition rates would be faster under higher moisture availability in the wet season and during dry‐season irrigation periods in the treatment plots, and that decomposition rates would be faster for species with higher quality leaves, independent of treatment. The rates of decomposition (k) were up to 2.4 times higher in irrigated plots than in control plots. The highestkvalues were shown byAnnona paludosa(0.97 to 1.26/yr) whileOcotea guianensis(0.73 to 0.85/yr) had the lowest values; intermediate rates were found forLacistema pubescens(0.91 to 1.02/yr) andVismia guianensis(0.91 to 1.08/yr). These four tree species differed significantly in leaf‐litter quality parameters (nitrogen, phosphorus, lignin, and cellulose concentrations, as well as lignin:nitrogen and carbon:nitrogen ratios), but differences in decomposition rates among tree species were not strictly correlated with leaf‐litter quality. Overall, our results show that dry‐season moisture deficits limit decomposition in Amazonian forest regrowth.
Distinguishing Sources of Ground Water Recharge by Using δ2H and δ18O
Authors: Blasch Kyle W. , Bryson Jeannie R.
Published: May 2007

Stable isotope values of hydrogen and oxygen from precipitation and ground water samples were compared by using a volumetrically based mixing equation and stable isotope gradient to estimate the season and location of recharge in four basins. Stable isotopes were sampled at 11 precipitation sites of differing elevation during a 2‐year period to quantify seasonal stable isotope contributions as a function of elevation. Supplemental stable isotope data collected by the International Atomic Energy Association during a 14‐year period were used to reduce annual variability of the mean seasonal stable isotope data. The stable isotope elevation relationships and local precipitation elevation relationships were combined by using a digital elevation model to calculate the total volumetric contribution of water and stable isotope values as a function of elevation within the basins. The results of these precipitation calculations were compared to measured ground water stable isotope values at the major discharge points near the terminus of the basins. Volumetric precipitation contributions to recharge were adjusted to isolate contributing elevations. This procedure provides an improved representation of recharge contributions within the basins over conventional stable isotope methods. Stable isotope values from wells and springs at the terminus of each basin were used to infer the elevations of precipitation important for recharge of the regional ground water flow system. Ancillary climatic, geologic, and stable isotope values were used to further constrain the location where precipitation is entering the ground water flow system.
Quantitative Interpretation of Specific Conductance Frequency Distributions in Karst
Authors: Massei N , Mahler B.J. , Bakalowicz M. , Fournier M. , Dupont J.P.
Published: May 2007

Use of the coefficient of variation (CV) of specific conductance has been a simple and popular approach to classifying karst aquifers; however, problems with this approach arise because specific conductance frequency distributions (CFDs) are usually multimodal and the use of the CV sometimes erroneously classifies aquifers in terms of their dominant flow type or recharge type. Here, we demonstrate a more rigorous analysis of the CFD, which gives insight into the water types contributing to spring flow. The CFD for a water year is separated into an additive series of normal distributions, each related to a hydrogeochemical population. For each water type, its mean, variance, and contribution to the overall CFD can be quantified and compared between water types and water years. We applied this method to 4 years of data collected at Barton Springs, Austin, Texas. Although the overall shape of the CFD changed from year to year, it could consistently be separated into the same set of normally distributed populations. We suggest that each population represents a water type resulting from a particular mode of aquifer functioning. Changes in the parameters describing the curves reflect aquifer response to climatic variations. The results suggest that no single parameter of specific conductance can be used to describe the degree of karst behavior of an aquifer but that the degree of karst behavior itself varies from year to year depending on hydrologic conditions.
Analyzing Bank Filtration by Deconvoluting Time Series of Electric Conductivity
Authors: Cirpka Olaf A. , Fienen Michael N. , Hofer Markus , Hoehn Eduard , Tessarini Aronne , Kipfer Rolf , Kitanidis Peter K.
Published: May 2007

Knowing the travel‐time distributions from infiltrating rivers to pumping wells is important in the management of alluvial aquifers. Commonly, travel‐time distributions are determined by releasing a tracer pulse into the river and measuring the breakthrough curve in the wells. As an alternative, one may measure signals of a time‐varying natural tracer in the river and in adjacent wells and infer the travel‐time distributions by deconvolution. Traditionally this is done by fitting a parametric function such as the solution of the one‐dimensional advection‐dispersion equation to the data. By choosing a certain parameterization, it is impossible to determine features of the travel‐time distribution that do not follow the general shape of the parameterization, i.e., multiple peaks. We present a method to determine travel‐time distributions by nonparametric deconvolution of electric‐conductivity time series. Smoothness of the inferred transfer function is achieved by a geostatistical approach, in which the transfer function is assumed as a second‐order intrinsic random time variable. Nonnegativity is enforced by the method of Lagrange multipliers. We present an approach to directly compute the best nonnegative estimate and to generate sets of plausible solutions. We show how the smoothness of the transfer function can be estimated from the data. The approach is applied to electric‐conductivity measurements taken at River Thur, Switzerland, and five wells in the adjacent aquifer, but the method can also be applied to other time‐varying natural tracers such as temperature. At our field site, electric‐conductivity fluctuations appear to be an excellent natural tracer.
Utilization of Decadal Tritium Variation for Assessing the Residence Time of Base Flow
Authors: Rose S.
Published: May 2007

An iterative algorithm is presented that allows the user to model the subsurface residence time of shallow ground water comprising stream base flow based on decadal scale variation of tritium concentrations. The algorithm accounts for the effects of radioactive decay, the shallow subsurface mixing of ground water with precipitation, and ground water flux. The inverse of the best‐fitting modeled flux through the saturated zone is equivalent to the residence time. The data required for this model include at least two measurements of tritium in base flow for a given stream location made at least a decade apart and the long‐term tritium input in precipitation for the region of interest. The model is sensitive to relatively small changes in tritium concentrations and is limited by analytic uncertainties to an accuracy of approximately ±5 years. The algorithm was applied to stream base flow for several basins in the Piedmont Province of Georgia in which tritium concentrations were measured during the early 1990s and again in the 2000s. The model results produced highly concordant residence times for three hydrogeologically similar basins in the Upper Ocmulgee Basin in North Central Georgia. The best estimate of the average residence time for ground water comprising base flow in this Piedmont basin using this new method is between approximately 14 and 18 years. These results are generally consistent with calculations made in previous studies, and these relatively long residence times can be attributed to the storage of water in the clay soils that dominate Piedmont Province watersheds.
A New Method for Laboratory Estimation of the Transverse Dispersion Coefficient
Authors: Massabò Marco , Catania Federico , Paladino Ombretta
Published: May 2007

We introduce a method for identifying the transverse dispersion coefficient in laboratory experiments based on the analytical solution of a pulse injection of a nonreactive solute in a soil column (cylindrical geometry) packed with a homogeneous porous medium. This method takes into account the effect of boundary conditions such as no flux on the column perimeter, and it does not need a priori knowledge of the longitudinal dispersion coefficient. Numerical applications of the method show that it is stable and robust and that the results are reasonably in accordance with those found using the classical maximum likelihood method.