bluuebunny/crossref_metadata_2025 huggingface dataset:
ASYMPTOTIC STABILITY I: COMPLETELY POSITIVE MAPS
Authors: ARVESON WILLIAM
Published: May 2004

We show that for every "locally finite" unit-preserving completely positive map P acting on a C*, there is a corresponding *-automorphism α of another unital C*-algebra such that the two sequences P, P2, P3, … and α, α2, α3, … have the same asymptotic behavior. The automorphism α is uniquely determined by P up to conjugacy. Similar results hold for normal completely positive maps on von Neumann algebras, as well as for one-parameter semigroups.

These results are operator algebraic counterparts of the classical theory of Perron and Frobenius on the structure of square matrices with nonnegative entries.
EINSTEIN–PODOLSKY–ROSEN ENTANGLED STATE REPRESENTATION FOR ANGULAR-MOMENTUM AND RADIUS ENTANGLEMENT
Authors: FAN HONG-YI , CHEN JUN-HUA
Published: May 2004

By comparison with the Einstein–Podolsky–Rosen coordinate-momentum entangled state, which is the common eigenvector of two particles' relative coordinate and total momentum, we construct a new quantum mechanical entangled state representation, namely, the entangled state representation of angular-momentum and radius. A concrete physical system which can embody the new quantum entanglement is analyzed.
DISORDER AND QUANTUM CRITICALITY IN d-WAVE SUPERCONDUCTORS
Authors: MEYER JULIA S. , GORNYI IGOR V. , ALTLAND ALEXANDER
Published: May 2004

To explain experimentally observed quasiparticle relaxation rates in the cuprate superconductors, Sachdev and collaborators recently proposed that the d-wave system may be close to a quantum critical point towards a superconducting state with an additional order parameter component of is- or id-wave symmetry. In the proximity of the transition, dynamical order parameter fluctuations modify the system properties. Here, we explore the influence of disorder on this interacting fluctuation regime. Our main finding is that unlike in the clean system, significant qualitative differences between is and id exist: In the is-case, due to the disorder-enhanced low-energy density of states, a secondary superconducting transition (with a strongly disorder-dependent Tc) takes place. In contrast, in the id-case essential features of the clean scenario are left intact by the disorder.
MODELING OF ARTIFICIALLY ACTIVATED MUSCLE AND APPLICATION TO FES CYCLING
Authors: GFÖHLER MARGIT , ANGELI THOMAS , LUGNER PETER
Published: May 2004

Functional Electrical Stimulation (FES) enables paraplegics to move their paralyzed limbs; the skeletal muscles are artificially activated. The purpose of this study is to establish a mechanical muscle model for an artificially activated muscle, based on a Hill-type muscle model. In comparison to modeling a physiologically activated muscle, for the artificially activated muscle, a number of additional parameters and their influence on the force generation has to be considered. The model was implemented into a forward dynamic simulation of paraplegic cycling. The stimulation patterns were optimized for surface stimulation of gluteus maximus, quadriceps, hamstrings, and peronaeus reflex. A simulation of a startup with 50% of maximum activation in the optimized stimulation intervals analyses drive torques and mean power per cycle and the resulting riding performance of the rider-cycle system. For validation of the simulation, the results were compared to measurements of the forces applied to the crank during steady-state cycling of a paraplegic test person.
INFLUENCE OF FLOW RATE AND AXIAL POSITION ON SHEAR STRESSES
Authors: SAKHAEIMANESH ALI A.
Published: May 2004

To locate the maximum and mean turbulent shear stresses in both time and space, and to determine how shear stresses depend on the flow rate and downstream measuring planes of the artificial heart valves, this study was carried out. Maximum and mean turbulent shear stresses estimated at 0.5D downstream of the valves showed a direct relationship with flow rate both in the Jellyfish and St. Vincent valves. The magnitude of both mean and maximum shear stresses in the Jellyfish valve was found to be higher than that of the St. Vincent valve at 0.5 and 1D downstream of the Jellyfish valve. Maximum shear stresses were found in close vicinity to the valve where highly disturbed flow with steep velocity gradients were observed.
Identification of the β-subunit for nongastric H-K-ATPase in rat anterior prostate
Authors: Pestov Nikolay B. , Korneenko Tatyana V. , Radkov Rossen , Zhao Hao , Shakhparonov Mikhail I. , Modyanov Nikolai N.
Published: May 2004

The structural organization of nongastric H-K-ATPase, unlike that of closely related Na-K-ATPase and gastric H-K-ATPase, is not well characterized. Recently, we demonstrated that nongastric H-K-ATPase α-subunit (αng) is expressed in apical membranes of rodent prostate. Its highest level, as well as relative abundance, with respect to α1-isoform of Na-K-ATPase, was observed in anterior lobe. Here, we aimed to determine the subunit composition of nongastric H-K-ATPase through the detailed analysis of the expression of all known X-K-ATPase β-subunits in rat anterior prostate (AP). RT-PCR detects transcripts of β-subunits of Na-K-ATPase only. Measurement of absolute protein content of these three β-subunit isoforms, with the use of quantitative Western blotting of AP membrane proteins, indicates that the abundance order is β1 > β3 ≫ β2. Immunohistochemical experiments demonstrate that β1 is present predominantly in apical membranes, coinciding with αng, whereas β3 is localized in the basolateral compartment, coinciding with α1. This is the first direct demonstration of the αng-β1 colocalization in situ indicating that, in rat AP, αng associates only with β1. The existence of αng-β1 complex has been confirmed by immunoprecipitation experiments. These results indicate that β1-isoform functions as the authentic subunit of Na-K-ATPase and nongastric H-K-ATPase. Putatively, the intracellular polarization of X-K-ATPase isoforms depends on interaction with other proteins.
Properties of a tonically active, sodium-permeable current in mouse urinary bladder smooth muscle
Authors: Thorneloe Kevin S. , Nelson Mark T.
Published: May 2004

Urinary bladder smooth muscle (UBSM) elicits depolarizing action potentials, which underlie contractile events of the urinary bladder. The resting membrane potential of UBSM is approximately −40 mV and is critical for action potential generation, with hyperpolarization reducing action potential frequency. We hypothesized that a tonic, depolarizing conductance was present in UBSM, functioning to maintain the membrane potential significantly positive to the equilibrium potential for K+ ( EK; −85 mV) and thereby facilitate action potentials. Under conditions eliminating the contribution of K+ and voltage-dependent Ca2+ channels, and with a clear separation of cation- and Cl−-selective conductances, we identified a novel background conductance ( Icat) in mouse UBSM cells. Icat was mediated predominantly by the influx of Na+, although a small inward Ca2+ current was detectable with Ca2+ as the sole cation in the bathing solution. Extracellular Ca2+, Mg2+, and Gd3+ blocked Icat in a voltage-dependent manner, with Ki values at −40 mV of 115, 133, and 1.3 μM, respectively. Although UBSM Icat is extensively blocked by physiological extracellular Ca2+ and Mg2+, a tonic, depolarizing Icat was detected at −40 mV. In addition, inhibition of Icat demonstrated a hyperpolarization of the UBSM membrane potential and decreased the amplitude of phasic contractions of isolated UBSM strips. We suggest that Icat contributes tonically to the depolarization of the UBSM resting membrane potential, facilitating action potential generation and thereby a maintenance of urinary bladder tone.
Apolipoprotein E and the Risk of Breast Cancer in African-American and Non-Hispanic White Women
Authors: Moore Rhonda J. , Chamberlain Robert M. , Khuri Fadlo R.
Published: May 2004

The apolipoprotein genetic polymorphism (APO E) is part of a broader paradigm, highlighting the role of gene-environment interactions as risk factors for human diseases such as cardiovascular disease, Alzheimer’s disease, dementia, atherosclerosis, multiple sclerosis, peripheral artery disease, diabetes, stroke, and most recently, cancer. APO E, a normal constituent of very-low-density lipoproteins and high-density lipoproteins, is involved in many functions, including lipid metabolism, cholesterol transport, tissue repair, immune response and regulation, as well as cell growth and differentiation. The location, frequency and functional effects of this gene have been reviewed elsewhere in terms of cardiovascular disease, Alzheimer’s disease, neuromuscular disease, multiple sclerosis, stroke and diabetes. However, while the majority of studies have examined the significance of APO E as a molecular marker for a variety of diseases in multiethnic populations, few evaluate its role as a putative marker of cancer susceptibility. Fewer explore the importance of APO E on the risk of breast cancer, although some report an association. None have been designed to study its relevance as a marker of breast cancer risk in multiethnic populations. The purpose of this review was to evaluate the association between APO E and the risk for breast cancer in non-Hispanic white and African-American women.
Chemotherapy in the Treatment of Advanced Gallbladder Cancer
Authors: Ishii Hiroshi , Furuse Junji , Yonemoto Naohiro , Nagase Michitaka , Yoshino Masahiro , Sato Tosiya
Published: May 2004

Objective: To clarify the role of chemotherapy for advanced gallbladder cancer (GBC). Methods: We reviewed 89 GBC patients: 21 admitted before 1997 were treated with a combination of cisplatin, epirubicin, and 5-fluorouracil (CEF); 25, admitted subsequently, received a combination of 5-fluorouracil, doxorubicin and mitomycin (FAM), and the remaining 43, ineligible for these trials, received supportive care. We investigated the relation between pretreatment clinical variables and long-term survival in these 89 subjects, and analyzed whether chemotherapy could favor longer survival. Results: There were no significant differences in survival time between the chemotherapy groups, whereas the response rate to the CEF regimen was 4-fold higher than to the FAM regimen (32 vs. 8%). Subgroup analysis suggested that chemotherapy favored longer survival in patients with a performance status (PS) of 0 or 1, but not in patients with a PS of 2. Cox regression analysis suggested a significant hazard reduction by chemotherapy in patients with a PS of 0 or 1, but not in patients with a PS of 2. Conclusions: GBC patients with poor PS should not be treated with chemotherapy at present. It is essential to design good clinical trials and develop more effective chemotherapy regimens.
Midkine Promoter Can Mediate Transcriptional Activation of a Fused Suicide Gene in a Broader Range of Human Breast Cancer Compared with c-erbB-2 Promoter
Authors: Yu Ling , Yamamoto Naohito , Kadomatsu Kenji , Muramatsu Takashi , Matsubara Shuichiro , Sakiyama Shigeru , Tagawa Masatoshi
Published: May 2004

We examined the expression level of the midkine (MK) and c-erbB-2 genes in both tumorous and matched nontumorous specimens from 18 patients with breast cancer. Expression of the MK and c-erbB-2 genes in nontumorous regions was relatively low, and the expression levels of both genes were not markedly different among the nontumorous samples. In contrast, the expression of the MK and c-erbB-2 genes in tumorous specimens was upregulated in 18 and 6 specimens, respectively. Regulatory regions of the MK gene were able to activate a reporter gene to a similar degree as those of the c-erbB-2 gene in the human breast cancer cell lines tested. Transfection of breast cancer cells with either the MK promoter- or the c-erbB-2 promoter-linked herpes simplex virus thymidine kinase gene increased their sensitivity to the prodrug ganciclovir. These data showed that the MK promoter activated a therapeutic gene in a wider range of human breast cancer than the c-erbB-2 promoter and suggest that MK promoter-mediated gene therapy is potentially more favorable in clinical settings.
Treatment of β-Thalassemia Patients with Recombinant Human Erythropoietin: Effect on Transfusion Requirements and Soluble Adhesion Molecules
Authors: Chaidos Aristeidis , Makis Alexandros , Hatzimichael Eleftheria , Tsiara Stavroula , Gouva Maria , Tzouvara Evangelia , Bourantas Konstantinos L.
Published: May 2004

The most common single genetic disorder and a major public health issue in Greece and other Mediterranean countries is β-thalassemia. Current therapeutic approaches for homozygous β-thalassemia entail blood transfusions and iron chelation therapy with deferoxamine or deferiprone for preventing tissue hemosiderosis. Recently, much effort has focused on various inducers of fetal hemoglobin (HbF) such as recombinant human erythropoietin (rHuEPO), especially in β-thalassemia intermedia. Ten adult patients, 5 with β-thalassemia major and 5 with β-thalassemia intermedia, received 150 IU/kg rHuEPO (epoetin-α) subcutaneously three times a week. Seven patients were transfused every 14–30 days and 3 with β-thalassemia intermedia were only occasionally transfused. The minimum duration of treatment was 12 weeks in order to define if there was any response. Transfusion intervals were modified according to the rHuEPO response to maintain stable Hb values. Lower transfusion requirements were observed in 5 patients after rHuEPO treatment (p = 0.028). In the 3 non-transfused patients, Hb values increased, and the patients are still being treated and followed up for a period ranging from 14 weeks to 2 years. Two patients with thalassemia major discontinued treatment after 12 weeks, as they did not achieve any response regarding transfusion requirements or Hb values. Pretreatment serum transferrin receptor levels were higher than in controls (p < 0.001) and significantly increased following rHuEPO treatment (p = 0.027). Patients had higher serum endothelin-3, sICAM-1 and sE-selectin values before rHuEPO treatment compared to controls (p < 0.001, p < 0.001 and p = 0.016, respectively), but these values were not altered during treatment. HbF values presented a slight, non-significant increase. rHuEPO treatment has a beneficial effect in transfusion-dependent β-thalassemia patients. Although a slight increase in HbF levels was observed, other possible mechanisms are probably involved. None of our patients experienced thrombotic complications and a rise in blood pressure.
HLA Antibodies and Neonatal Alloimmune Thrombocytopenia
Authors: Moncharmont P. , Dubois V. , Obegi C. , Vignal M. , Mérieux Y. , Gebuhrer L. , Rigal D.
Published: May 2004

A female baby with a severe thrombocytopenia at 18 × 109/l was born to a 29-year-old (gestation 2/partum 2) mother. Scattered petechiae were present on her legs, arms, chest and face, but there was no bleeding, infection, fever or hepatosplenomegaly. A platelet antibody screening immunocapture test was positive, which was performed on the mother’s serum 3, 12 and 38 days after delivery, but no platelet-specific antibodies were found by the monoclonal-antibody-specific immobilization of platelet antigen assay. The baby’s platelets and lymphocytes and the father’s platelets reacted strongly with the HLA antibodies present in the mother’s serum. The neonate was treated with intravenous human immunoglobulin (Tegeline®, 1 g/kg per day) 1, 2 and 3 days after delivery. The platelet count rose from 18 × 109/l on day 0 to 37 × 109/l on day 3 and to 227 × 109/l on day 12. No platelet transfusion was needed. Several factors which developed hereafter lead us to think that this neonatal alloimmune thrombocytopenia is due to the transplacental passage of maternal HLA antibodies to the baby.
Hemodialysis Using Heparin-Bound Hemophan in Patients at Risk of Bleeding
Authors: Lee Kyu-Beck , Kim Beom , Lee Yoon-Ha , Yoon Soo-Jin , Kang Woo-Hun , Huh Wooseong , Kim Dae-Joong , Oh Ha-Young , Kim Yoon-Goo
Published: May 2004

Background/Aims: Since heparin can bind to Hemophan, hemodialysis using heparin-bound Hemophan (HBH-HD) could be a useful modality in patients at risk of bleeding. We designed a simplified heparin binding technique and assessed the safety and efficiency of HBH-HD. Methods: To bind heparin to Hemophan, heparin solution (1 liter, 20 IU/ml saline) was recirculated through Hemophan (GFS plus 11, Gambro) for 1 h while the saline solution (700 ml/h) was removed. In 28 maintenance dialysis patients at risk of bleeding, we evaluated the heparin concentration (HC) and activated partial thromboplastin time (aPTT) during HBH-HD to assess the increased risk of bleeding. We compared the safety and efficiency of HBH-HD with that of routine hemodialysis with low-dose heparinization (R-HD) in a prospective cross-over study, and then analyzed the outcomes of 1,057 HBH-HD in 159 patients. Results: During HBH-HD, there was a slight increase in both HC (0.15 ± 0.03 IU/ml, p < 0.01) and aPTT (43.7 ± 5.7 s, p < 0.01) at 15 min after the initiation of dialysis compared to predialysis levels (0.11 ± 0.03 IU/ml and 37.5 ± 6.3 s). However, there was no increase in HC and aPTT at 60 min, 120 min and at the end of dialysis. In a cross-over study, aPTT during dialysis was markedly lower in HBH-HD than in R-HD (p < 0.01). The Kt/V (1.22 ± 0.31, p > 0.05) and urea clearance (136 ± 17 ml/min, p > 0.05) of HBH-HD did not significantly differ from those of R-HD (1.29 ± 0.57 and 136 ± 13 ml/min). However, the loss of total blood compartment volume of the dialyzer was greater in HBH-HD (17.5 ± 9.2%, p < 0.01) than in R-HD (2.9 ± 1.2%). Out of 1,057 HBH-HD, 982 HBH-HD (93%) were successfully completed while 75 HBH-HD (7%) resulted in severe clotting. Conclusion: We conclude that the HBH-HD could minimize the bleeding risk and be an efficient HD technique in patients at high risk of bleeding. Careful observation for extracorporeal clotting is, however, required during HBH-HD.
Bone Morphogenetic Protein-7 from Serum of Pregnant Mice Is Available to the Fetus through Placental Transfer during Early Stages of Development
Authors: Borovecki Fran , Jelic Mislav , Grgurevic Lovorka , Sampath Kuber T. , Bosukonda Dattatreyamurty , Vukicevic Slobodan
Published: May 2004

Background: BMP-7 is an important mediator of metanephric mesenchyme differentiation during kidney development. Gene knockout studies have shown that BMP-7 null mutation mice die shortly after birth due to renal failure, although the induction of metanephric structures has initially occurred (E11–E13). Materials and Methods: Iodinated BMP-7 was injected into the tail vein of pregnant mice and its availability to tissues and fetuses was further analyzed by tissue uptake, LM autoradiography and SDS-PAGE electrophoresis. Results: Studies on the distribution of 125I-BMP-7 injected through the tail vein of pregnant mice indicated that 125I-BMP-7 passed across the placenta and localized in developing fetal organs, in particular kidneys, up to day 14 of gestation. At later stages of pregnancy 125I-BMP-7 did not pass the trophoblasts of the placental barrier and did not enter the fetal blood vessels. Conclusion: The analysis of the distribution of 125I-BMP-7 from pregnant mice to fetal organs, in particular the kidney, suggests a cross-over of maternal circulating BMP-7 to the fetus through the placental barrier.
Renin-Angiotensin System Gene Polymorphisms: Its Impact on IgAN and Its Progression to End-Stage Renal Failure among Chinese in Singapore
Authors: Lau Yeow-Kok , Woo Keng-Thye , Choong Hui-Lin , Zhao Yi , Tan Hui-Boon , Chong Stephanie Mun-Chung Fook , Tan Eng-King , Yap Hui-Kim , Wong Kok-Seng
Published: May 2004

Background: Gene polymorphisms in angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin II type 1 receptor (ATR) had been associated with IgA nephropathy (IgAN) and its progression. Several studies on Caucasian and Japanese had reported contradicting results. We determined these polymorphisms in 118 Chinese patients with IgAN and 94 healthy Chinese to assess their clinical impact. Methods: Genotyping was performed with DNA from peripheral leukocytes, PCR amplification of the polymorphic sequence, restriction enzymes digestion, separation and identification of DNA fragments. Clinical data at renal biopsy and final status on renal function were determined from patients’ records. Results: Among controls, genotype distributions were in Hardy-Weinberg equilibrium. Comparing all IgAN patients with controls, AGT and ATR genotype distributions were similar whereas there was significant increase in the ACE DD genotype (p < 0.05). Comparing patients with end-stage renal failure (IgAN-ESRF) and without (IgAN-nonESRF), there was no difference in any of the three gene polymorphisms. But in contrast, there were significant differences in higher male prevalence (p < 0.05), increased serum creatinine at presentation (p < 0.05), more sclerosis (p < 0.01) and higher tubulointerstitial lesion score (p < 0.001) in the IgAN-ESRF group. Conclusion: Among the ACE, AGT and ATR gene polymorphisms, only the DD genotype may predispose the individual to IgAN in our Chinese population. In contrast to clinical and histological risk factors, these genetic variations showed no impact on disease progression to ESRF. It is unlikely that genotyping more patients will prove these genes useful. Nevertheless, preclinically determined genetic markers are very useful as risk factors for disease occurrence and as prognostic indices for disease progression. Therefore, continuing efforts should be made to look at other genes to find those with significance.
Urinary Excretion Rate of Tamm-Horsfall Protein Is Related to Salt Intake in Humans
Authors: Torffvit Ole , Melander Olle , Hultén U. Lennart
Published: May 2004

Background/Aims: Increased salt intake and enhanced salt sensitivity are implicated in the pathogenesis of hypertension. The aim of the present study was to investigate whether the urinary excretion rate of Tamm-Horsfall protein (THP) is dependent on salt intake in healthy, genetically hypertension-prone individuals. Methods: Thirty unrelated subjects (13 men and 17 women, mean age 48.1 ± 6.7 years) with at least one first-degree relative with primary hypertension were studied. After a baseline investigation, the study subjects were put on a low-salt diet (10 mmol of sodium and 70 mmol of potassium per day) for 1 week. During the second week, sodium chloride capsules (230 mmol/day) were added to the diet to achieve a high-salt intake of 240 mmol/day. Urine samples (24-hour and overnight collections) were collected before the baseline investigation and at the end of the high- and low-salt diet weeks. The salt sensitivity was calculated as the difference between the blood pressure during high salt intake and the blood pressure during low salt intake. Results: A low salt intake induced a decrease in the urinary excretion rate of THP during the night (11.7 µg/min) compared with baseline (19.5 µg/min; p < 0.05) and high salt intake (23.1 µg/min; p < 0.01). Furthermore, a greater response in blood pressure to a high salt intake, i.e. high salt sensitivity, was associated with increased excretion of THP in urine during the change to high salt intake (r = 0.38, p < 0.05). Conclusion: We were able to confirm that urinary excretion of THP is dependent on sodium intake. Patients with a high salt sensitivity, i.e. an exaggerated blood pressure response to high salt intake, responded to the high salt intake with an even greater increase in the urinary excretion rate of THP. The mechanism underlying this response is still unknown, but it might indicate that distal nephron function in healthy, genetically hypertension-prone individuals is altered.
Urethral Reconstruction after Total Penectomy for Urethral Cancer
Authors: de Jesus Carlos M.N. , Kawano P.R. , Yamamoto H.A. , Trindade Filho J.C.S. , Agostinho A.D. , Correa L.A.
Published: May 2004

A 59-year-old white man developed a ventral ulcer with irregular limits in the middle portion of the penis. The result of the pathologic analysis was compatible with invasive squamous cell urethral carcinoma. A total penectomy was performed. In these cases, the usually recommended urinary diversion is perineal urethrostomy. However, due to the specifications of the case, perineal urethrostomy could not be performed. The literature did not offer any other alternative for patients with this same condition. Therefore, a urethral reconstruction using a groin skin flap had to be performed.
Relationship between Complications due to Prostate Biopsy and the Scores of Pain and Discomfort
Authors: Celebi Ilhan , Irer Bora , Kefi Aykut , Kurtulan Erkan , Goktay Yigit , Ergin Tufan
Published: May 2004

Introduction: Transrectal ultrasound (TRUS)-guided prostate biopsy is routinely performed in the prostate-specific antigen era. In this study, we evaluated morbidity and complications observed in patients undergoing TRUS-guided prostate biopsy following intrarectal lidocaine application and the relation of these complications to pain and discomfort. Patients and Methods: Between January 2000 and August 2002, a total of 128 patients underwent TRUS-guided prostate biopsy. The procedure was carried out following an intrarectal application of 10 cm3 2% lidocaine gel. Immediately after the biopsy, pain and discomfort scores were determined using a 10-point linear visual analog scale. The patients were seen 10 days later and questioned for complications. Results: At least one complication was observed in 107 patients (84%). Most frequent complications were macroscopic hematuria (90%), hematochezia (36%), and hematospermia (13%). The mean pain and discomfort scores of the patients were found to be correlated to each other (p < 0.01). The complication-negative group had significantly lower pain and discomfort scores (p < 0.01). The scores of the patients with hematochezia were significantly higher than the scores of the patients with other complications (p < 0.01). Conclusions: Minor complications like hematuria, hematochezia, and hematospermia are frequently seen in patients undergoing TRUS-guided prostate biopsies. The pain and discomfort scores may be predictors of minor complications, particularly of rectal bleeding.
Periprostatic Lidocaine Infiltration and/or Synthetic Opioid (Meperidine or Tramadol) Administration Have No Analgesic Benefit during Prostate Biopsy
Authors: Bozlu Murat , Atıcı Şebnem , Ulusoy Ercüment , Canpolat Bülent , Çayan Selahittin , Akbay Erdem , Schellhammer Paul F. , Oral Uğur
Published: May 2004

Objectives: To examine in a prospective, randomized, double-blind, placebo-controlled study the analgesic effect of periprostatic nerve block and/or intravenous synthetic opioid administration during a 12-core prostate biopsy. Patients and Methods: Patients were prospectively randomized to receive unilateral periprostatic lidocaine administration and/or intravenous synthetic opioid (meperidine or tramadol) administration. Placebo groups received sterile normal saline. Unilateral infiltration was performed and biopsy was begun on this side. The degree of pain was recorded using the visual analog scale/numeric analog scale (VAS/NAS) score before the procedure, during probe introduction into the rectum, during unilateral periprostatic nerve blockade, during the first 6-core biopsy and during the second 6-core biopsy, and 30 min after biopsy completion. Results: Most of the patients had mild or moderate pain (VAS/NAS <6) during the actual biopsy procedure. However, no significant differences existed between the groups with regard to the pain scores at any time (p > 0.05). Compared with pain scores, no significant differences existed between the first 6-core (blocked side) and second 6-core biopsies (p > 0.05). Conclusion: Periprostatic lidocaine infiltration and/or intravenous synthetic opioid analgesics are not beneficial in significantly reducing pain during biopsy. We think that most of the patients do have pain during biopsy, however the intensity of pain is tolerable and does not require analgesics.
The Same-Pedicle Concept for Continent Urinary Diversion Using a Yang-Monti Reconfigured Tube
Authors: Kato Haruaki , Igawa Yasuhiko , Nishizawa Osamu
Published: May 2004

Objective: To facilitate the anastomosis of a continent valve to the umbilicus or a suitable skin area, we used a reconfigured tube made from the same segment of the intestinal reservoir as that used to construct the urinary pouch. Materials and Methods: Seven patients underwent continent ileal-pouch formation using a reconfigured ileal tube following cystectomy for bladder cancer. Two irradiated patients and 1 patient with neurogenic bladder underwent continent colon-pouch construction with a reconfigured colon tube. Results: The average length of the reconfigured ileal tube was 5 cm, while the colon tube was maximally 10 cm long. All procedures were technically straightforward. All the continent pouches functioned well, without catheterization difficulties. Conclusions: Since the Yang-Monti tube and the pouch are easily mobilized, being based on the same vascular pedicle, and can therefore bridge the gap, making the umbilical anastomosis was greatly facilitated. Sufficient support for the tube is provided by the pouch.
Tension-Free Vaginal Tape and Female Stress Incontinence: Further Evidence of Effectiveness
Authors: Fiori M. , Gunelli R. , Mercuriali M. , Bercovich E.
Published: May 2004

Objectives: Female stress incontinence is a frequent and distressing event with subsequent impact on quality of life. The tension-free vaginal tape (TVT) technique is considered to fulfill the criteria for an ideal surgical procedure and we therefore reviewed our cases to further analyze its effectiveness. Materials and Methods: 57 patients suffering from stress incontinence with grade 1–2 cystocele underwent the TVT operation. During follow-up (mean 22.2 months), the short- and long-term results were investigated. Results: 91.3% of patients achieved complete resolution of previous stress incontinence in the early postoperative period. Early complications occurred in 8.7% of patients. Follow-up (mean 22.2 months) highlighted the stabilization of positive outcomes in 87.7% of cases. No postoperative modification of sexual habits and a significant improvement in quality of life were reported by all patients. Conclusion: The results of our study confirm that the TVT technique for stress incontinence is an easy to perform procedure which is safe, effective and long-lasting.
Use of Buccal Mucosa Patch Graft for Recurrent Large Urethrocutaneous Fistula after Hypospadias Repair
Authors: Kiss András , Pirót László , Karsza Levente , Merksz Miklós
Published: May 2004

Introduction: To assess the effectiveness of buccal mucosa patch graft in the treatment of recurrent large urethrocutaneous fistula after hypospadias repair. Materials and Methods: A free graft of buccal mucosa was used for closure in 7 boys (mean age 4.8 years) with large (>4 mm) urethocutaneous fistula. Four fistulas were in the midshaft, 2 of them penoscrotal and 1 coronal type. All patients had undergone at least two previous unsuccessful fistula repairs, and 3 of them had undergone three attempts for closure. Fistula repairs were similar in all cases. Results: The repair was successful in 6 out of 7 cases, and in these cases the urinary stream was good after the removal of the catheter. The unsuccessful case was the coronal one. Conclusion:Based on our experience it seems that in cases with recurrent large fistula after hypospadias reconstruction, the use of buccal mucosa patch graft for closure is a good treatment choice.
Changing Paradigms in Concepts on Dental Caries: Consequences for Oral Health Care
Authors: Fejerskov O.
Published: May 2004

Kuhn proposed in his Structure of Scientific Revolutions (1962) that the theoretical framework of a science (paradigm) determines how each generation of researchers construes a causal sequence. Paradigm change is infrequent and revolutionary; thereafter previous knowledge and ideas become partially redundant. This paper discusses two paradigms central to cariology. The first concerns the most successful caries-preventive agent: fluoride. When it was thought that fluoride had to be present during tooth mineralisation to ‘improve’ the biological apatite and the ‘caries resistance’ of the teeth, systemic fluoride administration was necessary for maximum benefit. Caries reduction therefore had to be balanced against increasing dental fluorosis. The ‘caries resistance’ concept was shown to be erroneous 25 years ago, but the new paradigm is not yet fully adopted in public health dentistry, so we still await real breakthroughs in more effective use of fluorides for caries prevention. The second paradigm is that caries is a transmittable, infectious disease: even one caused by specific microorganisms. This paradigm would require caries prevention by vaccination, but there is evidence that caries is not a classical infectious disease. Rather it results from an ecological shift in the tooth-surface biofilm, leading to a mineral imbalance between plaque fluid and tooth and hence net loss of tooth mineral. Therefore, caries belongs to common ‘complex’ or ‘multifactorial’ diseases, such as cancer, cardiovascular diseases, diabetes, in which many genetic, environmental and behavioural risk factors interact. The paper emphasises how these paradigm changes raise new research questions which need to be addressed to make caries prevention and treatment more cost-effective.
Dental Plaque as a Microbial Biofilm
Authors: Marsh P.D.
Published: May 2004

New technologies have provided novel insights into how dental plaque functions as a biofilm. Confocal microscopy has confirmed that plaque has an open architecture similar to other biofilms, with channels and voids. Gradients develop in areas of dense biomass over short distances in key parameters that influence microbial growth and distribution. Bacteria exhibit an altered pattern of gene expression either as a direct result of being on a surface or indirectly as a response to the local environmental heterogeneity within the biofilm. Bacteria communicate via small diffusible signalling molecules (e.g. competence-stimulating peptide, CSP; autoinducer 2); CSP induces both genetic competence and acid tolerance in recipient sessile cells. Thus, rates of gene transfer increase in biofilm communities, and this is one of several mechanisms (others include: diffusion-reaction, neutralization/inactivation, slow growth rates, novel phenotype) that contribute to the increased antimicrobial resistance exhibited by bacteria in biofilms. Oral bacteria in plaque do not exist as independent entities but function as a co-ordinated, spatially organized and fully metabolically integrated microbial community, the properties of which are greater than the sum of the component species. A greater understanding of the significance of dental plaque as a mixed culture biofilm will lead to novel control strategies.
Salivary Proteins: Protective and Diagnostic Value in Cariology?
Authors: van Nieuw Amerongen A. , Bolscher J.G.M. , Veerman E.C.I.
Published: May 2004

Saliva is essential for a lifelong conservation of the dentition. Various functions of saliva are implicated in the maintenance of oral health and the protection of our teeth: (i) The tooth surface is continuously protected against wear by a film of salivary mucins and proline-rich glycoprotein. (ii) The early pellicle proteins, proline-rich proteins and statherin, promote remineralization of the enamel by attracting calcium ions. (iii) Demineralization is retarded by the pellicle proteins, in concert with calcium and phosphate ions in saliva and in the plaque fluid. (iv) Several salivary (glyco)proteins prevent the adherence of oral microorganisms to the enamel pellicle and inhibit their growth. (v) The salivary bicarbonate/carbonate buffer system is responsible for rapid neutralization of acids. An overview is presented on the major antimicrobial systems in human saliva. Not only the well-known major salivary glycoproteins, including mucins, proline-rich glycoprotein and immunoglobulins, but also a number of minor salivary (glyco)proteins, including agglutinin, lactoferrin, cystatins and lysozyme, are involved in the first line of defense in the oral cavity. Besides, small cationic antimicrobial peptides, e.g. defensins, cathelicidin and the histatins, have come into focus. These are potentially suited as templates for the design of a new generation of antibiotics, since they kill a broad spectrum of microorganisms, while hardly evoking resistance, in contrast to the classical antibiotics.
Systemic versus Topical Fluoride
Authors: Hellwig E. , Lennon Á.M.
Published: May 2004

The actual mechanism of fluoride action is still a subject of debate. A dogma has existed for many decades, that fluoride has to be ingested and acts mainly pre-eruptively. However, recent studies concerning the systemic effect of fluoride supplementation concluded that the caries-preventive effect of fluoride is almost exclusively posteruptive. Moreover, epidemiologists have cast doubt on the validity of the ‘old’ studies dealing with fluoride use. The concept of the posteruptive fluoride effect is supported by in vitro and in situ investigations demonstrating that the mode of action of fluoride can be attributed mainly to its influence on de- and remineralization kinetics of dental hard tissues. Therefore, topical fluoride application (e.g. in the form of fluoridated dentifrices) should be encouraged. There are still important questions open that need to be answered despite existing knowledge about the caries-preventive effect of fluoride.
The Future Role of a Molecular Approach to Pulp-Dentinal Regeneration
Authors: Tziafas D.
Published: May 2004

The ultimate goal of a regenerative pulp treatment strategy is to reconstitute normal tissue continuum at the pulp-dentin border, regulating tissue-specific processes of tertiary dentinogenesis. Experimental investigations in mature teeth have shown that a network of extracellular matrix molecules and growth factors signal tertiary dentinogenesis. Application of dentin matrix components or growth factors in deep dentinal cavities stimulated up-regulation of biosynthetic activity of primary odontoblasts (reactionary dentin formation). Pulp-capping studies with a broad spectrum of biological agents, including growth factors and extracellular matrix molecules, showed formation of osteodentin and/or tertiary dentinogenesis (reparative dentin formation). Promising biologically active substances should be subjected to careful evaluation in well-designed preclinical investigations as well as in long-term clinical trials before their introduction in clinical practice.
Perinatal Food Deprivation Induces Marked Alterations of the Hypothalamo-Pituitary-Adrenal Axis in 8-Month-Old Male Rats both under Basal Conditions and after a Dehydration Period
Authors: Sebaai Naima , Lesage Jean , Breton Christophe , Vieau Didier , Deloof Sylvie
Published: May 2004

Dehydration is a classic homeostatic stressor in rats that leads to a series of endocrine responses including stimulation of the hypothalamo-pituitary-adrenal (HPA) axis. During the last decade, it has been well established that perinatal food restriction is associated with the onset of diseases in adults. Our previous demonstration of long-term alterations in HPA axis activity in both basal conditions and after a 72-hour dehydration period in 4-month-old rats exposed to a 50% maternal food restriction (FR50) in late gestation and lactation prompted us to investigate whether such perinatal undernutrition further affects HPA axis activity in mature animals. As previously described in 4-month-old rats under basal conditions, 8-month-old FR50 rats showed reduced body weight and an enhanced ratio between mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) mRNA levels in the hippocampus, as well as increased pro-opiomelanocortin (POMC) mRNA levels in the adenohypophysis. In addition, numerous additional alterations appeared in mature rats. In the hypothalamus, levels of vasopressin (VP) mRNAs were increased both in the paraventricular nucleus (PVN) and in the supraoptic nucleus (SON). In the adenohypophysis, GR and prohormone-convertase 2 (PC2) mRNA levels were significantly increased, whereas prohormone-convertase 1 (PC1) mRNA was not affected by maternal undernutrition. Interestingly, undernourished animals exhibited high plasma levels of total and free corticosterone in spite of normal corticotropin (ACTH) levels, an indication that HPA basal activity is enhanced by maternal undernutrition in 8-month-old animals. Dehydration for 72 h induced a rise in ACTH plasma levels, but did not modify total and free corticosterone plasma levels in 8-month-old FR50 animals. In the adenopituitary, POMC mRNA levels were decreased after dehydration but PC1 mRNA levels were unaffected. The present study indicates that maternal food restriction during the perinatal period dramatically affects the activity of the HPA axis until the age of 8 months. We speculate that higher basal HPA activity and an inadequate HPA response after dehydration in mature animals may contribute to diseases such as hypertension, known to develop with aging in perinatally growth-restricted rats.
Cloning of Prodynorphin cDNAs from the Brain of Australian and African Lungfish: Implications for the Evolution of the Prodynorphin Gene
Authors: Dores Robert M. , Sollars Cristina , Lecaude Stephanie , Lee Jenny , Danielson Phillip , Alrubaian Jasem , Lihrman Isabelle , Joss Jean M.P. , Vaudry Hubert
Published: May 2004

In mammals the opioids Met-enkephalin and Leu-enkephalin are derived from a common precursor, proenkephalin, and as a result these neuropeptides are co-localized in enkephalinergic neurons. The mammalian scheme for enkephalinergic networks is not universal for all classes of sarcopterygian vertebrates. In an earlier study, distinct Met- and Leu-enkephalin-positive neurons were detected in the central nervous system (CNS) of the African lungfish, Protopterus annectens. More recently, characterization of proenkephalin cDNAs separately cloned from the CNS of P. annectens and the Australian lungfish, Neoceratodus forsteri, revealed that the proenkephalin gene in these species encodes only Met-enkephalin-related opioids. In the current study a full-length prodynorphin cDNA (accession No. AY 445637) was cloned and sequenced from the CNS of N. forsteri. In addition to encoding α-neoendorphin, dynorphin A and dynorphin B sequences unique to the lungfish, two Leu-enkephalin sequences, flanked by paired basic amino acid proteolytic cleavage sites, were detected in this precursor. The partial sequence of a P. annectens prodynorphin cDNA (accession No. AY445638) also encoded a Leu-enkephalin sequence and a novel YGGFF sequence. The presence of the Leu-enkephalin sequence in the lungfish prodynorphin precursors would explain the origin of the distinct Leu-enkephalin-positive neurons found in the African lungfish CNS. The realization that Met-enkephalin and Leu-enkephalin can be derived from distinct opioid-coding precursor genes calls into question the interpretation of comparative immunohistochemical studies that have mapped ‘enkephalinergic’ networks in non-mammalian vertebrates.
Mu Opioid Modulation of Oxytocin Secretion in Late Pregnant and Parturient Rats
Authors: Kutlu Selim , Yilmaz Bayram , Canpolat Sinan , Sandal Suleyman , Ozcan Mete , Kumru Selahattin , Kelestimur Haluk
Published: May 2004

We have investigated effects of µ- and ĸ-opioid agonists and antagonists on plasma oxytocin levels and noradrenaline content in the supraoptic nucleus (SON) and paraventricular nucleus (PVN) of 20-day pregnant rats. β-Endorphin, oxytocin, estrogen and progesterone profiles in late pregnant and parturient rats were also sought. Stage of estrous cycle was monitored by vaginal smear, and pro-estrous animals were left overnight with male. In the first set of experiments, pregnant rats were monitored and decapitated on days 20 and 21 and after the delivery of second pup. In the second set, 20-day pregnant rats were intracerebroventricularly infused with morphine (50 µg/10 µl), U50,488H (ĸ-agonist; 50 µg/10 µl), clocinnamox (µ-antagonist; 50 µg/10 µl) and norbinaltorphimine (ĸ-antagonist; 50 µg/10 µl). Controls received saline alone. Serum estrogen and progesterone levels were measured by enzyme immunoassay, and plasma oxytocin and β-endorphin by radioimmunoassay. Noradrenaline and its metabolite (3,4-dihydroxyphenylglycol) were determined in micropunched hypothalamic nuclei by HPLC-ECD. In parturient rats, oxytocin levels were increased (p < 0.05) and β-endorphin decreased (p < 0.01) compared to 20-day pregnant animals. Serum progesterone concentrations progressively declined towards parturition (p < 0.001). Clocinnamox raised oxytocin levels (p < 0.01) while U50,488H caused decreases (p < 0.05). Noradrenaline content was elevated by clocinnamox in the SON (p < 0.01) and PVN (p < 0.05) compared to control values. Other agonists and antagonists had no significant effect on the noradrenergic neurotransmission or oxytocin secretion. We suggest that noradrenaline may mediate the inhibitory effects of µ-opioids on oxytocin release. Our findings have also shown that ĸ-opioid receptors are not involved in modulation of oxytocin neurons in late pregnant rats.
Neutrophil Gelatinase-Associated Lipocalin: A Novel Early Urinary Biomarker for Cisplatin Nephrotoxicity
Authors: Mishra Jaya , Mori Kiyoshi , Ma Qing , Kelly Caitlin , Barasch Jonathan , Devarajan Prasad
Published: May 2004

Background: Cisplatin is one of the most widely used chemotherapeutic agents, but the risk of nephrotoxicity frequently hinders the use of higher doses to maximize its antineoplastic effects. The lack of early biomarkers has impaired our ability to initiate potential therapeutic or preventive interventions in cisplatin nephrotoxicity in a timely manner. In this study, we have explored the expression and urinary excretion of neutrophil gelatinase-associated lipocalin (NGAL) in a mouse model of cisplatin-induced nephrotoxic injury. Methods: Mice were subjected to intraperitoneal injections of 20 mg/kg (high dose) or 5 mg/kg (low dose) cisplatin. The expression of NGAL was measured in the kidney and urine by Western analysis and immunofluorescence, and compared to changes in serum creatinine and urinary N-acetyl-β-D-glucosaminidase (NAG). Results: Cisplatin resulted in tubule cell necrosis and apoptosis following the high dose, but not the low dose. By Western analysis, NGAL protein was rapidly induced in the kidney within 3 h of high-dose cisplatin. By immunofluorescence, NGAL was induced predominantly in proximal tubule cells in a punctate cytoplasmic distribution, reminiscent of a secreted protein. NGAL was easily detected in the urine by Western analysis within 3 h of cisplatin administration in a dose- and duration-dependent manner. By comparison, changes in urinary NAG or serum creatinine were not evident until 96 h after cisplatin. Using defined concentrations of purified recombinant NGAL, urinary NGAL excretion following cisplatin administration was quantified to be in the 20–80 ng/ml range. Conclusion: The results indicate that NGAL represents an early and quantitative urinary biomarker for cisplatin nephrotoxicity.