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1.
J Phys Condens Matter ; 30(4): 045901, 2018 Jan 31.
Article in English | MEDLINE | ID: mdl-29214983

ABSTRACT

The formation of a localized surface plasmon resonance (SPR) spectrum of randomly distributed gold nanoparticles in the surface layer of silicate float glass, generated and implanted by UV ArF-excimer laser irradiation of a thin gold layer sputter-coated on the glass surface, was studied by the T-matrix method, which enables particle agglomeration to be taken into account. The experimental technique used is promising for the production of submicron patterns of plasmonic nanoparticles (given by laser masks or gratings) without damage to the glass surface. Analysis of the applicability of the multi-spheres T-matrix (MSTM) method to the studied material was performed through calculations of SPR characteristics for differently arranged and structured gold nanoparticles (gold nanoparticles in solution, particles pairs, and core-shell silver-gold nanoparticles) for which either experimental data or results of the modeling by other methods are available. For the studied gold nanoparticles in glass, it was revealed that the theoretical description of their SPR spectrum requires consideration of the plasmon coupling between particles, which can be done effectively by MSTM calculations. The obtained statistical distributions over particle sizes and over interparticle distances demonstrated the saturation behavior with respect to the number of particles under consideration, which enabled us to determine the effective aggregate of particles, sufficient to form the SPR spectrum. The suggested technique for the fitting of an experimental SPR spectrum of gold nanoparticles in glass by varying the geometrical parameters of the particles aggregate in the recurring calculations of spectrum by MSTM method enabled us to determine statistical characteristics of the aggregate: the average distance between particles, average size, and size distribution of the particles. The fitting strategy of the SPR spectrum presented here can be applied to nanoparticles of any nature and in various substances, and, in principle, can be extended for particles with non-spherical shapes, like ellipsoids, rod-like and other T-matrix-solvable shapes.

2.
J Hum Hypertens ; 29(10): 583-91, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25631217

ABSTRACT

In a population with high sodium consumption, we assessed relation between brachial and central blood pressures, elastic properties of large arteries, echocardiographic left ventricular diastolic function and sodium reabsorption as fractional urinary lithium excretion in proximal (FELi) and fractional sodium reabsorption in distal tubules assessed using the endogenous lithium clearance. Mean±s.d. age of 131 treated hypertensive patients (66 men and 65 women) was 61.9±7.5 years. We found significant interaction between left ventricular diastolic function and FELi with respect to the values of brachial blood pressure: systolic (SBP), diastolic (DBP) and mean blood pressure (MBP) (all PINT<0.03). In patients with FELi below the median value and impaired left ventricular diastolic function, the values of SBP (149.3 vs 132.5 mm Hg; P=0.005), DBP (85.1 vs 76.1 mm Hg; P=0.001), MBP (106.5 vs 94.9 mm Hg; P=0.001), central SBP (SBPC) (137.4 vs 122.0 mm Hg; P=0.01), central DBP (DBPC) (84.8 vs 76.0 mm Hg; P=0.003), central MBP (MBPC) (106.9 vs 95.9 mm Hg; P=0.007), aortic pulse wave augmentation (18.0 vs 13.5 mm Hg; P=0.03), pulse wave velocity (14.6 vs 12.5 m s(-1); P=0.02) and central aortic pulse wave augmentation index (155.7% vs 140.9%; P=0.01) were significantly higher than in patients with normal left ventricular diastolic function. Such relationships were not observed in the entire group and patients with FELi above the median value. In the hypertensive population with high sodium intake, increased sodium reabsorption in proximal tubules may affect blood pressure parameters and arterial wall damage, thus contributing to the development of left ventricular diastolic function impairment.


Subject(s)
Heart Ventricles/physiopathology , Hypertension/physiopathology , Sodium, Dietary/adverse effects , Sodium/metabolism , Vascular Stiffness/physiology , Ventricular Dysfunction, Left/etiology , Ventricular Function, Left/physiology , Blood Pressure/physiology , Echocardiography, Doppler , Female , Follow-Up Studies , Heart Ventricles/diagnostic imaging , Humans , Hypertension/complications , Hypertension/metabolism , Male , Middle Aged , Pulse Wave Analysis , Retrospective Studies , Sodium, Dietary/administration & dosage , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/physiopathology
3.
Arch Med Sadowej Kryminol ; 64(3): 147-57, 2014.
Article in English | MEDLINE | ID: mdl-25693172

ABSTRACT

The subject matter of this publication is the legal assessment of endogenous infection - the specific type of hospital infections. The main aim of the publication is to answer the question of whether medical and legal grounds exist for civil liability for endogenous infections and for treating those infections as cases of medical malpractice or medical events. The research method adopted is a case study. The authors have analysed a civil lawsuit for compensation instituted by an infected patient against a Polish hospital, adjudicated in 2013. The main conclusion of the publication is to postulate distinguishing medical malpractice from complications resulting from the reactions of the human body to treatment. The authors argue that endogenous infections should be treated as the latter-mentioned of these two cases.

4.
Nanotechnology ; 20(50): 505705, 2009 Dec 16.
Article in English | MEDLINE | ID: mdl-19923657

ABSTRACT

Nanosized metal particles of various configurations embedded in surface regions of glass have great potential as nonlinear optical materials for photonic devices. We have prepared Ag/Au nanoparticles in core-shell configuration in soda-lime silicate glass by double-ion implantation and investigated their structural characteristics by anomalous small-angle x-ray scattering (ASAXS) and transmission electron microscopy. Measurements at x-ray energies slightly below the Au L(3) edge indicate the formation of bimetallic Ag/Au shells in some of the nanoparticles for high-dose ion implantation. An element-specific analysis of the ASAXS results allowed us not only to validate and quantify the core-shell structure, but simultaneously also the composition of the shells. Hollow nanoparticles were found for an Au-Ag implantation sequence, whereas an Ag-Au sequence generates a diluted core composition. The shift of the maximum position of optical absorption of the samples due to surface plasmon resonance of bimetallic nanoparticles, as monitored by optical spectroscopy, revealed the considerable influence of the respective particle configuration.

5.
J Nanosci Nanotechnol ; 9(2): 1659-62, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19441594

ABSTRACT

X-ray absorption fine structure (XAFS) technique was used to analyze structural geometry of Ag atoms introduced into soda-lime silicate glass and soda aluminosilicate glass by ion-exchange method. The results show that Ag+ ion in soda aluminosilicate glass takes a coordination number of 1.6 with a Ag-O distance of 2.20 A when the ion-exchange ratio x is smaller than 0.47 and of 2.28 A when x is larger than 0.47. The introduced Ag+ ions are stabilized at the non-bridge oxygen (NBO) sites when x is lower than 0.47. The Na+ ions in AlO4 (O4 represents the bridging oxygen) sites are exchanged by Ag+ ions after all Na+ in NBO sites are replaced. The disorder of Ag-O coordination increases gradually with increasing x from 0.24 to 0.47 in soda aluminosilicate glass and increases dramatically when x is larger than 0.47. Ag+ ions takes a coordination number of 1.6 in the ion-exchanged soda-lime silicate glass and of 1.3 after subsequently thermal treatment with the same Ag-O distance of 2.14 A. Debye-Waller factor (DWF) of Ag-O coordination in soda aluminosilicate glass is higher than that in soda-lime silicate glass. Small Ag cluster has a reduced interatomic distance and a larger DWF. Ag nanoparticle in sample Ag-7 is in a state of tensile stress.

6.
Nanoscale Res Lett ; 4(11): 1380-3, 2009 Aug 11.
Article in English | MEDLINE | ID: mdl-20628450

ABSTRACT

Bimetallic, initially spherical Ag/Au nanoparticles in glass prepared by ion implantation have been irradiated with intense femtosecond laser pulses at intensities still below the damage threshold of the material surface. This high-intensity laser processing produces dichroism in the irradiated region, which can be assigned to the observed anisotropic nanoparticle shapes with preferential orientation of the longer particle axis along the direction of laser polarization. In addition, the particle sizes have considerably been increased upon processing.

7.
Neuroscience ; 146(4): 1758-71, 2007 Jun 08.
Article in English | MEDLINE | ID: mdl-17478054

ABSTRACT

Antioxidative properties of alpha-lipoic acid (LA) are widely investigated in different in vivo and in vitro models. The aim of this study was to examine whether LA attenuates oxidative stress induced in rats by reserpine, a model substance frequently used to produce Parkinsonism in animals. Male Wistar rats were treated with reserpine (5 mg/kg) and LA (50 mg/kg) separately or in combination. The levels of reduced glutathione (GSH), glutathione disulfide (GSSG), nitric oxide (NO) and S-nitrosothiols as well as activities of glutathione peroxidase (GPx), glutathione-S-transferase (GST) and L-gamma-glutamyl transpeptidase (gamma-GT) were determined in the striatum and prefrontal cortex homogenates. In the striatum and prefrontal cortex a single dose of reserpine significantly enhanced levels of GSSG and NO but not that of S-nitrosothiols when compared with control. In the striatum, LA administered jointly with reserpine markedly increased the concentration of GSH and decreased GSSG level. In the prefrontal cortex, such treatment produced only an increasing tendency in GSH level but caused no changes in GSSG content. In both structures LA injected jointly with reserpine markedly decreased NO concentrations but did not cause significant changes in S-nitrosothiol levels when compared with control. Enzymatic activities of GPx and GST were intensified by LA in the striatum. In the prefrontal cortex, GPx activity was not altered, while that of GST was decreased. Gamma-GT activity was attenuated by reserpine in the striatum while LA reversed this effect. Such changes were not observed in the prefrontal cortex. The mode of LA action in the striatum during the reserpine-evoked oxidative stress strongly suggests that this compound may be of therapeutic value in the treatment of Parkinson's disease.


Subject(s)
Antioxidants/pharmacology , Antipsychotic Agents/pharmacology , Corpus Striatum/drug effects , Oxidative Stress/drug effects , Prefrontal Cortex/drug effects , Reserpine/pharmacology , Thioctic Acid/pharmacology , Animals , Brain Chemistry/drug effects , Drug Interactions , Glutathione/metabolism , Glutathione Peroxidase/metabolism , Male , Nitric Oxide/metabolism , Rats , Rats, Wistar
8.
J Matern Fetal Neonatal Med ; 19(9): 551-5, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16966123

ABSTRACT

OBJECTIVE: Uterine artery Doppler is becoming a routine part of pregnancy surveillance in high-risk pregnancies. Which blood flow velocity waveform index to measure is debated and the 'notch' in early diastole is not widely accepted, as it is a subjective measure. The aim of the present study was to evaluate the different indices in the prediction of adverse outcome of pregnancies suspected for intrauterine fetal growth restriction (IUGR). METHODS: Uterine artery blood flow was recorded in 217 pregnancies admitted for Doppler ultrasound surveillance due to suspected IUGR. The median gestational age at examination was 38 weeks (range 25-42 weeks). Only cases having bilateral uterine artery notching were included in the evaluation. The uterine artery Doppler spectrum was analyzed for different indices, including evaluation of notch and end-diastolic velocities. Umbilical artery Doppler velocimetry was also performed. The outcome variables chosen were: a small-for-gestational-age (SGA) newborn, preterm birth, and abdominal delivery. ROC-curve calculations were used to compare the different indices. RESULTS: The uterine artery blood velocity pulsatility index (PI) and resistance indices (RI) were the best predictors of adverse outcome of pregnancy. Apart from premature birth, the systolic/end-diastolic ratio was less predictive of adverse outcome. The indices including only diastolic blood velocities were the least predictive of adverse outcome. The group with notch velocity above end-diastolic velocity was compared with those having notch velocity below the end-diastolic velocity. No difference in outcome was seen between the two groups. CONCLUSIONS: RI and PI as measures of third trimester utero-placental vascular impedance are the best predictors of adverse outcome of IUGR-suspected pregnancies.


Subject(s)
Blood Flow Velocity , Fetal Growth Retardation/diagnostic imaging , Ultrasonography, Doppler, Color , Ultrasonography, Prenatal , Uterus/blood supply , Arteries/diagnostic imaging , Female , Fetal Growth Retardation/physiopathology , Humans , Placental Circulation , Predictive Value of Tests , Pregnancy , Pregnancy Trimester, Third , Pregnancy, High-Risk , Uterus/diagnostic imaging , Vascular Resistance
9.
Ultrasound Obstet Gynecol ; 25(5): 459-63, 2005 May.
Article in English | MEDLINE | ID: mdl-15846767

ABSTRACT

OBJECTIVE: Signs of increased uterine artery vascular impedance in mid-gestation are strongly related to pre-eclampsia later in pregnancy. Whether this is true for the late third trimester is, however, unclear. The aim of the present study was to analyze the frequency of increased uterine artery vascular impedance in the third trimester, and its relationship to abnormal umbilical artery Doppler and adverse outcome of pregnancy. METHODS: This was a retrospective study of uterine and umbilical artery Doppler velocimetry in 570 pregnancies complicated by pre-eclampsia. The managing clinician was informed only about the umbilical artery flow. The Doppler recordings were related to severity of pre-eclampsia, prematurity, fetal growth restriction, and rates of Cesarean section and admission to neonatal intensive care. RESULTS: Increased umbilical artery vascular impedance was seen in 59 cases (10.4%), seven having absent or reversed end-diastolic flow. Uterine artery notching was seen in 145 cases (25%), 88 (15%) having bilateral notches. Either increased uterine artery pulsatility index (PI) or notching, or both, were seen in 207 women (36.3%). In 108 women with severe pre-eclampsia, 38 (35.2%) had uterine artery notching. Signs of increased uteroplacental vascular impedance were more common in severe than in mild pre-eclampsia (57.4% vs. 31.4%), in premature than in term pregnancies (70.9% vs. 28.4%), and were more prevalent than abnormality in the umbilical artery (36.3% vs. 10.4%). CONCLUSION: Only one-third of pre-eclamptic cases showed signs of increased uterine artery vascular impedance in the third trimester. However, signs of increased vascular impedance were much more frequent in the uterine than in the umbilical arteries and were strongly related to adverse outcome of pregnancy.


Subject(s)
Pre-Eclampsia/diagnostic imaging , Ultrasonography, Doppler/methods , Ultrasonography, Prenatal/methods , Uterus/blood supply , Vascular Resistance , Adolescent , Adult , Arteries/diagnostic imaging , Cesarean Section , Female , Fetal Growth Retardation/diagnostic imaging , Humans , Infant, Newborn , Intensive Care, Neonatal , Middle Aged , Pre-Eclampsia/physiopathology , Pregnancy , Pregnancy Outcome , Pregnancy Trimester, Third , ROC Curve , Regional Blood Flow , Retrospective Studies , Umbilical Arteries/diagnostic imaging , Uterus/diagnostic imaging , Vascular Resistance/physiology
10.
Ultrasound Obstet Gynecol ; 24(2): 147-53, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15287051

ABSTRACT

OBJECTIVE: In previous pilot studies, fetal vein of Galen (GV) blood velocity has been shown to be non-pulsatile in normal pregnancies. A pulsating pattern in high-risk pregnancies has been related to adverse outcome of pregnancy. The aim of this study was to establish reference ranges for fetal cerebral venous blood flow and compare them to the recordings in high-risk pregnancies in terms of predicting adverse perinatal outcome. METHODS: The GV, straight sinus (SS) and transverse sinus (TS) were located by color Doppler ultrasound in 189 normal pregnancies between 23 and 43 weeks of gestation. Recordings were also made in 102 pregnancies complicated by pregnancy-induced hypertension and/or intrauterine growth restriction. The following parameters were measured: peak systolic velocity, minimum diastolic velocity, time-averaged maximum velocity, pulsatility index for veins (PIV) and preload index (PLI). GV pulsations were noted. In high-risk pregnancies, Doppler measurements were correlated to pregnancy outcome, including emergency operative intervention and/or neonatal distress. Umbilical vein and umbilical, uterine and middle cerebral artery blood velocities were also recorded at the same time. RESULTS: In normal pregnancy, pulsating venous blood velocity was observed in GV in 8% of cases, in SS in 79% of cases and in TS in 100% of cases. GV and SS maximum velocity increased with gestational age and TS-PIV showed linear decreasing values and TS-PLI showed increasing values with gestational age. In high-risk pregnancies, pulsating blood velocity in the GV was found in 59 (58%) cases and was related to adverse outcome of pregnancy including mortality. Abnormal values for TS-PIV and PLI and SS maximum velocity were found in nine, six and five cases, respectively and were only related to perinatal mortality. GV pulsations were more frequent than umbilical venous pulsations. CONCLUSIONS: Of the fetal cerebral veins studied, the presence of pulsations in the GV seems to be the best predictor of adverse outcome of high-risk pregnancy. Pulsations in the GV are more frequent than in the umbilical vein and might therefore appear earlier during worsening fetal condition, and thus be of potential value for fetal surveillance in high-risk pregnancies.


Subject(s)
Cerebral Veins/diagnostic imaging , Pregnancy, High-Risk/physiology , Ultrasonography, Prenatal/methods , Blood Flow Velocity , Cerebral Veins/physiology , Female , Humans , Pregnancy , Pregnancy Outcome , Pulsatile Flow , Reference Values , Ultrasonography, Doppler, Color
11.
Bone Marrow Transplant ; 30(3): 157-60, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12189533

ABSTRACT

Between October 1989 and February 1997, 13 patients with refractory or relapsed seminomas were treated with high-dose chemotherapy (HDCT) as part of consecutive phase I/II studies. Six patients had failed prior cisplatin-based first-line treatments and seven patients had also failed cisplatin-based salvage treatments. After HDCT 4/12 (33%) patients became disease-free, 4/12 (33%) patients achieved partial remissions and 4/12 (33%) patients suffered progressive disease despite HDCT. One patient developed multiorgan failure and died. With a median follow-up of 4.5 years (range 3.4 to 8 years) five patients (38%) are alive and eight patients (62%) have died. Patients with non-pulmonary visceral metastases, with short relapse-free intervals and with cisplatin-refractory tumors were more likely to fail. HDCT can be curative in seminoma patients even if offered as second salvage treatment.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Seminoma/therapy , Adult , Antineoplastic Combined Chemotherapy Protocols/toxicity , Bone Marrow Transplantation , Cisplatin/administration & dosage , Digestive System Neoplasms/secondary , Hematopoietic Stem Cell Transplantation , Humans , Male , Middle Aged , Peripheral Blood Stem Cell Transplantation , Remission Induction , Retrospective Studies , Salvage Therapy , Seminoma/mortality , Seminoma/pathology , Survival Analysis , Transplantation, Autologous , Treatment Failure
12.
Ultrasound Obstet Gynecol ; 20(2): 117-21, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12153660

ABSTRACT

BACKGROUND: Studies on blood flow velocity in the fetal middle cerebral artery have revealed signs of brain sparing in chronic hypoxia. These signs of brain sparing can disappear in the terminal case, but whether this applies to the whole brain or only parts of it is unknown. METHODS: Velocity waveforms of the middle cerebral, anterior cerebral and posterior cerebral arteries were recorded in 221 pregnancies complicated by pregnancy-induced hypertension. The presence of brain sparing (pulsatility index < 2 standard deviations) was noted and correlated to outcome of pregnancy, including emergency operative intervention and/or neonatal distress. RESULTS: Signs of brain sparing in the anterior cerebral artery were found in 90 fetuses, and in the middle cerebral and posterior cerebral arteries in 52 and 65, respectively. Signs of brain sparing in the anterior cerebral artery showed the strongest relationship to adverse perinatal outcome. The anterior cerebral artery was the only vessel in which signs of brain sparing were predictive of perinatal mortality. CONCLUSIONS: Velocimetry of the anterior cerebral artery appears to be superior to that of the middle cerebral and posterior cerebral arteries as a means to predict adverse perinatal outcome. Anterior cerebral artery brain sparing may therefore be less transitory than sparing in the middle cerebral and posterior cerebral arteries, possibly suggesting that the frontal lobes are spared longer than the lateral and occipital regions of the fetal brain.


Subject(s)
Brain/embryology , Cerebral Arteries/physiopathology , Fetal Diseases/physiopathology , Hypertension/physiopathology , Hypoxia, Brain/physiopathology , Pregnancy Complications, Cardiovascular/physiopathology , Ultrasonography, Doppler , Ultrasonography, Prenatal , Adult , Anterior Cerebral Artery/diagnostic imaging , Anterior Cerebral Artery/physiopathology , Blood Flow Velocity , Brain/blood supply , Cerebral Arteries/diagnostic imaging , Chronic Disease , Echoencephalography , Female , Fetal Diseases/diagnostic imaging , Humans , Hypertension/diagnostic imaging , Middle Cerebral Artery/diagnostic imaging , Middle Cerebral Artery/physiopathology , Posterior Cerebral Artery/diagnostic imaging , Posterior Cerebral Artery/physiopathology , Pregnancy , Pregnancy Complications, Cardiovascular/diagnostic imaging , Pulsatile Flow , Regional Blood Flow
13.
Ultrasound Obstet Gynecol ; 19(3): 229-34, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11936080

ABSTRACT

OBJECTIVE: Reverse end-diastolic flow is the most pathological type of the umbilical artery flow velocity waveform. We aimed to investigate whether additional prognostic information can be obtained from umbilical artery waveforms in cases with reverse end-diastolic flow. SUBJECTS AND METHODS: Umbilical artery Doppler velocity waveforms from 44 fetuses with reverse end-diastolic flow were analyzed and the following parameters measured: the highest amplitude and the area below the maximum velocity curve of forward and reverse flow (A, B and C, D, respectively) and the duration of forward and reverse flow (Tc and Td, respectively). Ratios A/B, C/D and Tc/Td were calculated. The cut-off values for A/B, C/D and Tc/Td with the best predictive values for perinatal death were established with the help of receiver operating characteristics curves. The three curves were compared with each other. RESULTS: Of the three ratios, A/B and C/D had the best capacity to predict perinatal death. Both ratios had acceptable sensitivities, specificities and positive predictive values. In this regard, A/B and C/D were comparable. The cut-off values for A/B and C/D were 4.3 and 4.52, respectively. Survivors had I significantly higher A/B and C/D ratios than non-survivors (P = 0.0001 and 0.0003, respectively). Significantly more fetuses with A/B or C/D below the established cut-off values had pulsations in the venous system (P < 0.05). In fetuses with a gestational age < =210 gestational days the survival rate was significantly higher in those with A/B or C/D above the cut-off values (P = 0.03 and 0.003, respectively). CONCLUSIONS: The A/B or C/D ratio can be used for quantification of the reverse end-diastolic flow waveforms in the umbilical artery and may offer additional information to the evaluation of fetal condition.


Subject(s)
Fetal Growth Retardation/physiopathology , Fetal Monitoring/methods , Pregnancy Outcome , Ultrasonography, Prenatal , Umbilical Arteries/diagnostic imaging , Blood Flow Velocity , Diastole/physiology , Female , Fetal Death , Fetal Growth Retardation/diagnostic imaging , Fetal Growth Retardation/mortality , Humans , Pregnancy , Probability , Prospective Studies , Sampling Studies , Sensitivity and Specificity , Statistics, Nonparametric , Survival Rate , Ultrasonography, Doppler/methods , Umbilical Arteries/physiopathology
14.
Appl Environ Microbiol ; 68(3): 1440-5, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11872499

ABSTRACT

Microbiologically influenced corrosion (MC) of steel has been attributed to the activity of biofilms that include anaerobic microorganisms such as iron-respiring bacteria, yet the mechanisms by which these organisms influence corrosion have been unclear. To study this process, we generated mutants of the iron-respiring bacterium Shewanella oneidensis strain MR-1 that were defective in biofilm formation and/or iron reduction. Electrochemical impedance spectroscopy was used to determine changes in the corrosion rate and corrosion potential as a function of time for these mutants in comparison to the wild type. Counter to prevailing theories of MC, our results indicate that biofilms comprising iron-respiring bacteria may reduce rather than accelerate the corrosion rate of steel. Corrosion inhibition appears to be due to reduction of ferric ions to ferrous ions and increased consumption of oxygen, both of which are direct consequences of microbial respiration.


Subject(s)
Biofilms/growth & development , Iron/metabolism , Shewanella/metabolism , Steel/chemistry , Corrosion , DNA Transposable Elements , Mutagenesis, Insertional , Oxidation-Reduction , Oxygen Consumption , Shewanella/genetics , Shewanella/growth & development
15.
J Perinat Med ; 29(5): 399-407, 2001.
Article in English | MEDLINE | ID: mdl-11723841

ABSTRACT

Knowledge of fetal hemodynamic physiology has developed enormously during the last two decades due to Doppler ultrasound. Some of this knowledge has been utilized for routine surveillance of high-risk pregnancies. The prediction of fetal hypoxia before the development of life lasting sequel is of major importance, especially in the very premature case with absent end-diastolic blood flow in the umbilical artery before lung maturity. This review gives an overview of the present knowledge in this field.


Subject(s)
Blood Flow Velocity/physiology , Fetal Diseases/diagnostic imaging , Hypoxia/embryology , Ultrasonography, Doppler , Ultrasonography, Prenatal , Adrenal Glands/blood supply , Brain/blood supply , Coronary Vessels , Female , Humans , Hypoxia/diagnostic imaging , Placenta/blood supply , Pregnancy , Umbilical Arteries/diagnostic imaging , Umbilical Arteries/physiology
16.
Eur J Obstet Gynecol Reprod Biol ; 99(1): 14-8, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11604180

ABSTRACT

BACKGROUND: Pulsation in the flow velocity waveform in the umbilical vein is related to perinatal mortality but the flow velocity waveform in the fetal vein of Galen is normally even and without fluctuation. OBJECTIVES: To establish whether blood flow velocity pulsations in the vein of Galen in high-risk pregnancies are related to outcome. STUDY DESIGN: The vein of Galen was located by colour Doppler ultrasound in 102 pregnancies complicated by severe pregnancy-induced hypertension. The blood velocity waveform was recorded by pulsed Doppler within 2 days of delivery and the presence pulsations related to pregnancy outcome, including emergency operative intervention and neonatal distress. Umbilical artery and vein and uterine artery blood flow velocity waveform were also recorded at the same time. The clinicians managing the women were unaware of the venous flow results. RESULTS: Pulsation were present in the vein of Galen in 68 cases and in the umbilical vein in 21. Both were significantly related to adverse outcome. Pulsations in the vein of Galen were seen in all seven perinatal deaths. CONCLUSIONS: Since umbilical venous pulsation are a late sign of fetal compromise, and pulsations in the vein of Galen seem to appear earlier, thus being an intermediate sign of fetal compromise that might be of great value for fetal surveillance.


Subject(s)
Blood Flow Velocity , Cerebral Veins/embryology , Infant Mortality , Pregnancy Outcome , Asphyxia/diagnostic imaging , Birth Weight , Cerebral Veins/diagnostic imaging , Female , Gestational Age , Humans , Infant, Newborn , Predictive Value of Tests , Pregnancy , Pregnancy Complications/diagnostic imaging , Ultrasonography, Doppler, Color , Umbilical Veins/diagnostic imaging
17.
J Synchrotron Radiat ; 8(Pt 2): 539-41, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11512843

ABSTRACT

The thermal expansion behaviour of silver fcc has been described by an anharmonic Einstein model using EXAFS data in the temperature range between 10 and 300 K. The linear expansion coefficient of a bulk silver foil agrees well with X-ray diffraction data. In the case of silver particles embedded in a silicate glass matrix, this parameter shows an increase for particles of 3.2 nm in size by 70% whereas samples with an average size of particles of 5.1 nm show no changes compared with bulk fcc. The increase for small particles reflects the size effect as well as the influence of the surrounding matrix of glass. The results reveal a substantial influence of the distribution of particle sizes on the expansion coefficient.

18.
Transfusion ; 41(8): 1008-13, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11493732

ABSTRACT

BACKGROUND: The purpose of this study was to analyze the CD34 cell collection efficiency (CE) of automated leukapheresis protocols of two blood cell separators (Spectra, COBE [AutoPBSC protocol] and AS104, Fresenius [PBSC-Lym, protocol]) for peripheral blood progenitor cell (PBPC) harvest in patients with malignant diseases. STUDY DESIGN AND METHODS: PBPCs were collected by the Spectra AutoPBSC protocol in 95 patients (123 collections) and the AS104 PBSC-Lym protocol in 87 patients (115 harvests). Patients underwent a median of one (range, 1-4) conventional-volume apheresis procedure of 10.8 L (9.0-13.9) to obtain a target cell dose of > or =2.5 x 10(6) CD34+ cells per kg. RESULTS: The median overall CD34 CE was significantly better on the AS104 than on the Spectra: 55.8 percent versus 42.4 percent (p = 0.000). This was also true below (59.2% vs. 50.1%; p = 0.022) and above (51.2% vs. 41.3%; p = 0.001) the preleukapheresis threshold of 40 CD34+ cells per microL needed to collect a single-apheresis autograft. However, at > or =40 circulating CD34+ cells per microL, both cell separators achieved the target of > or =2.5 x 10(6) CD34+ cells per kg. The CD34 CE dropped significantly, from 59.2 percent at <40 cells per microL to 51.2 percent at > or =40 cells per microL on the AS104 (p = 0.017) and from 50.1 percent to 41.3 percent on the Spectra (p = 0.033). CONCLUSION: Whereas the CD34 CE was significantly different with the AS104 and the Spectra, the CD34 CE of both machines correlated inversely with peripheral blood CD34+ cell counts, showing a significant decline with increasing numbers of circulating CD34+ cells. Nevertheless, at > or 40 preapheresis CD34+ cells per microL, sufficient hematopoietic autografts of > or =2.5 x 10(6) CD34+ cells per kg were harvested by a single conventional-volume (11 L) leukapheresis on both cell separators.


Subject(s)
Antigens, CD34/blood , Leukapheresis/instrumentation , Adolescent , Adult , Blood Cell Count , Blood Specimen Collection/standards , Female , Humans , Leukapheresis/standards , Male , Middle Aged , Statistics, Nonparametric
19.
Eur J Ultrasound ; 12(3): 197-202, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11423243

ABSTRACT

OBJECTIVE: Prospectively evaluate semi-quantitative computer analysis of power Doppler (PD) signals in the placenta, tetal brain, lung, liver, kidney and spleen in high-risk pregnancies in relationship to perinatal outcome and also to compare tissue blood flow in the fetal brain and placenta with Doppler velocimetry. METHODS: PD signals were recorded in 180 high-risk pregnancies between 27 and 41 weeks of gestation. Images from PD angiographic scans were transmitted for computer analysis of pixel intensity. Mean flow signal intensity was recorded for each organ. The PD brain/lung ratio was calculated. The PD results were plotted on reference values and related to perinatal outcome. Middle cerebral (MCA), umbilical (UA) and uterine artery (Ut. A) velocimetry was also performed. RESULTS: High-risk pregnancies displayed lower PD signal intensity from the placenta, fetal lung, liver and kidney as compared to normals. However, the brain and spleen signals showed higher intensities suggesting increased tissue perfusion. PD signals from the fetal brain, lung, placenta and PD brain/lung ratio were correlated with perinatal outcome. The PD signal intensity from the fetal liver, kidney and spleen showed poor correlation with perinatal outcome. Fetal brain tissue blood flow showed better correlation with the outcome than MCA velocimetry. Placental tissue blood flow results were similar in predicting outcome to those obtained by means of UA and Ut. A velocimetry. CONCLUSION: In comparison with conventional Doppler velocimetry, computer analysis of PD signals, give similar results in the prediction of adverse perinatal outcome.


Subject(s)
Pregnancy Outcome , Pregnancy, High-Risk , Rheology , Ultrasonography, Doppler , Ultrasonography, Prenatal , Blood Flow Velocity , Female , Fetus/physiology , Humans , Middle Cerebral Artery/diagnostic imaging , Placenta/blood supply , Pregnancy , Pulsatile Flow , Regional Blood Flow , Umbilical Arteries/diagnostic imaging , Uterus/blood supply
20.
Transfusion ; 41(2): 196-200, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11239222

ABSTRACT

BACKGROUND: The impact of amifostine on PBPC mobilization with paclitaxel and ifosfamide plus G-CSF was assessed. STUDY DESIGN AND METHODS: Forty patients with a median age of 34 years (range, 19-53) who had germ cell tumor were evaluated for high-dose chemotherapy. Patients were randomly assigned to receive either a single 500-mg dose of amifostine (Group A, n = 20) or no amifostine (Group B, n = 20) before mobilization chemotherapy with paclitaxel (175 mg/m(2)) given over 3 hours and ifosfamide (5 g/m(2)) given over 24 hours (TI) on Day 1. G-CSF at 10 microg per kg per day was given subsequent to TI with or without amifostine from Day 3 until the end of leukapheresis procedures. RESULTS: In 2 (10%) of 20 patients receiving amifostine and 3 (15%) of 20 patients not receiving it, no PBPC separation was performed because of mobilization failure. No significant differences were observed in the study arms with regard to the time from chemotherapy until first PBPC collection or the number of apheresis procedures needed to harvest more than 2.5 x 10(6) CD34+ cells per kg. Furthermore, leukapheresis procedures yielded comparable doses of CD34+ cells per kg (3.4 x 10(6) vs. 3.6 x 10(6); p = 0.82), MNCs per kg (2.7 x 10(8) vs. 2.6 x 10(8); p = 0.18), and CFU-GM per kg (15.9 x 10(4) vs. 19.3 x 10(4); p = 0.20). Patients in Group A had higher numbers of circulating CD34+ cells on Day 10 (103.0/microL vs. 46.8/microL; p = 0.10) and on Day 11 (63.0/microL vs.14.3/microL; p = 0.04) than did patients in Group B. CONCLUSION: Administration of a single dose of amifostine before chemotherapy with TI mobilized higher numbers of CD34 cells in the circulation, but did not enhance the overall collection efficiency in the present trial.


Subject(s)
Amifostine/pharmacology , Granulocyte Colony-Stimulating Factor/pharmacology , Hematopoietic Stem Cell Mobilization , Ifosfamide/pharmacology , Paclitaxel/pharmacology , Adult , Amifostine/administration & dosage , Antigens, CD34/blood , Blood Specimen Collection , Dose-Response Relationship, Drug , Hematopoietic Stem Cells/immunology , Humans , Middle Aged , Neoplasms, Germ Cell and Embryonal/drug therapy , Pilot Projects , Prospective Studies
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