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PubMed2003

On the accuracy of some in vitro models for mechanical studies of maxillary removable partial dentures.

OBJECTIVES: Comparative in vitro/in vivo studies show wide differences in functional strain magnitudes and patterns of functional strain distribution in prosthetic devices. The aim of this study was to evaluate the accuracy of three in vitro models for biomechanical studies of prosthetic devices. METHODS: Strain gages were attached to the test RPDs of six subjects. In vitro maxillary models with simple (model A), intermediate (model B) and advanced (model C) features for the anatomical simulation of supporting structures were manufactured for each subject. The dentures were subjected to two separate series of standardized functional and laboratorial loading tests. The principal maximum strain value (epsilon (1)) obtained for each gage and experiment was used to calculate the intra-experiment variance and inter-experiment variance for the in vivo and in vitro experiments. The integrated strain gage difference value between the in vitro and in vivo data (Sigma(diff)) was calculated for every loading test and compared to the in vivo inter-experiment variance with ANOVA and Scheffés test. RESULTS: The bite forces recorded were similar for each subject and loading position and between the two loading sessions. The inter- and intra-experiment variance was found to be higher for in vivo loadings than for in vitro. Results showed that the (Sigma(diff)) values for model B and model C were significantly different from the in vivo strain inter-experiment variance (p<0.05). SIGNIFICANCE: This study showed that the anatomical simulation of in vitro models is insufficient to allow for accurate mechanical analyses of maxillary RPDs and that only simple verifications of the strain levels in prosthetic appliances can be attained in vitro.

Aged↗
PubMed1993

Electromyography and the study of sports movements: a review.

Within electromyography (EMG), a particular specialty has been developed wherein the aim is to use EMG for the study of muscular function and co-ordination. This area of research is usually called kinesiological EMG. The general aims of kinesiological EMG are to analyse the function and co-ordination of muscles in different movements and postures, in healthy subjects as well as in the disabled, in skilled actions as well as during training, in humans as well as in animals, under laboratory conditions as well as during daily or vocational activities. This is often done by a combination of electromyographical and kinesiological or biomechanical measurement techniques. Because there are over 400 skeletal muscles in the human body and both irregular and complex involvement of the muscles may occur in neuromuscular diseases and in voluntary occupational or sports movements, it is impossible to sample all of the muscles of the entire body during the performance of complex motor skills. In addition, the measurement of kinesiological EMG in sport and specific field circumstances, such as the track and/or soccer field, the alpine ski slope, the swimming pool and the ice rink, demands a specific technological and methodological approach, adaptable to both the field and the sport circumstances. Sport movement techniques and skills, training approaches and methods, ergonomic verification of the human-machine interaction have, amongst others, a highly specialized muscular activity in common. The knowledge of such muscular action in all its aspects, its evaluation and its feedback should allow for the optimization of movement, of sports materials, of training possibilities and, in the end, of sports performance. Drawing conclusions from a review of the EMG research of 32 sports, covering over 100 different complex skills, including methodological approaches, is an impossible task. We have attempted to set standards concerning the EMG methodology at the beginning of this review. Electromyography and sports is a vast area and a complete review is impossible, as information will be found scattered in many different journals, including those on the sports sciences, ergonomics, biomechanics, applied physiology, in different congress proceedings, and so on. Consequently, many important aspects and possibly important publications may have been omitted from this review.

Electromyography↗
PubMed2006

Functional genomics of innate host defense molecules in normal human monocytes in response to Aspergillus fumigatus.

Aspergillus fumigatus induces the release of innate immune-related molecules from phagocytic cells early in the course of infection. Little is known, however, about the complex expression profiles of the multiple genes involved in this response. We therefore investigated the kinetics of early gene expression in human monocytes (HMCs) infected with conidia of A. fumigatus using DNA microarray analysis. Total RNA from HMCs at 0, 2, 4, and 6 h was extracted, linearly amplified, hybridized onto Affymetrix HG133 Plus 2.0 gene chips, and analyzed with an Affymetrix scanner. Changes in gene expression were calculated as a ratio of those expressed by infected versus control HMCs. Aspergillus fumigatus induced differential regulation of expression in 1,827 genes (P < 0.05). Genes encoding cytokines and chemokines involved in host defense against A. fumigatus, including interleukin-1beta (IL-1beta), IL-8, CXCL2, CCL4, CCL3, and CCL20, as well as the opsonin long pentraxin 3, were up-regulated during the first 2 to 6 h, coinciding with an increase in phagocytosis. Simultaneously, genes encoding CD14, ficolin1, and MARCO were down-regulated, and genes encoding IL-10 and matrix metalloproteinase 1 were up-regulated. Up-regulation of the genes encoding heat shock proteins 40 and 110 and connexins 26 and 30 may point to novel molecules whose role in the pathogenesis of aspergillosis has not been previously reported. Verification of the transcriptional profiling was obtained for selected genes by reverse transcription-PCR and enzyme immunoassay. Thus, A. fumigatus conidia induced a coordinated expression of genes important in host defense and immunomodulation.

Aspergillosis↗
PubMedDate not supplied

Continuous peripheral nerve blocks with stimulating catheters.

BACKGROUND AND OBJECTIVES: This study evaluated the efficacy of stimulating catheters used for continuous peripheral nerve blocks as a means of immediate verification and confirmation of correct catheter position. METHODS: This observational study presents our experience with 130 stimulating catheters used in 40 intersternocleidomastoid, 24 axillary, 47 femoral, and 19 lateral midfemoral sciatic nerve blocks. Placement characteristics (amperage, depth of introducer needle or catheter insertion, elicited motor responses), subsequent postoperative analgesia, and catheter position evaluated with the radiopaque dye analysis were all studied. RESULTS: Except in femoral blocks, characteristics of motor responses elicited (1 Hz, 0,1 ms) by the introducer assembly and catheter differed. The amperage required to elicit motor responses typically was higher with the catheter than with the introducer needle (1.6 [0.2 to 4 mA] v 0.5 [0.4 to 1 mA] P <.0001). The ability to elicit a motor response with the stimulating catheter correlated with successful clinical anesthesia in 124 cases. Opacified radiography showed no aberrant position in these cases. Three catheters for upper limb block failed to stimulate, provided poor anesthesia, and had radiologic evidence of aberrant position. Even though they failed to stimulate, 3 catheters for sciatic block functioned well, and the opacified radiography showed correct position. CONCLUSION: The ability to electrostimulate nerves using an in situ catheter increases success rate in catheter placement for continuous peripheral nerve blocks. Further controlled investigations are necessary to compare this technique with more conventional methods in terms of cost and utility for various peripheral nerve blocks.

Adult↗
PubMed2004

Simultaneous optimization of beam orientations, wedge filters and field weights for inverse planning with anatomy-based MLC fields.

As an alternative between manual planning and beamlet-based IMRT, we have developed an optimization system for inverse planning with anatomy-based MLC fields. In this system, named Ballista, the orientation (table and gantry), the wedge filter and the field weights are simultaneously optimized for every beam. An interesting feature is that the system is coupled to Pinnacle3 by means of the PinnComm interface, and uses its convolution dose calculation engine. A fully automatic MLC segmentation algorithm is also included. The plan evaluation is based on a quasi-random sampling and on a quadratic objective function with penalty-like constraints. For efficiency, optimal wedge angles and wedge orientations are determined using the concept of the super-omni wedge. A bound-constrained quasi-Newton algorithm performs field weight optimization, while a fast simulated annealing algorithm selects the optimal beam orientations. Moreover, in order to generate directly deliverable plans, the following practical considerations have been incorporated in the system: collision between the gantry and the table as well as avoidance of the radio-opaque elements of a table top. We illustrate the performance of the new system on two patients. In a rhabdomyosarcoma case, the system generated plans improving both the target coverage and the sparing of the parotide, as compared to a manually designed plan. In the second case presented, the system successfully produced an adequate plan for the treatment of the prostate while avoiding both hip prostheses. For the many cases where full IMRT may not be necessary, the system efficiently generates satisfactory plans meeting the clinical objectives, while keeping the treatment verification much simpler.

Algorithms↗
PubMed1990

Alternate methods for the determination of atrial capture threshold utilizing the telemetered intracardiac electrogram.

Periodic determination of pacemaker capture threshold is important to ensure appropriate pacemaker function. During dual chamber pacing, it is sometimes difficult to identify evidence of atrial depolarization on surface electrocardiography (ECG), and this can interfere with the ability to ascertain atrial capture. We describe new methods for determining atrial capture threshold using a standard telemetered endocardial atrial electrogram (AEGM). For the first method, the atrial output is decremented until loss of atrial capture is demonstrated by the appearance of native P wave activity on the AEGM. The atrial capture threshold can then be accurately determined as the point at which a stepwise increase in atrial output results in extinction of the native P wave activity. The second method uses the direct visualization of the AEGM recorded between the ring electrode and pacemaker generator during unipolar (lead tip electrode) pacing. This requires the presence of a bipolar lead. Using this method of recording, it is possible to identify a signal after the atrial stimulus artifact during atrial capture, which disappears with loss of capture. This signal is consistent with a paced "evoked atrial potential" and allows verification of atrial capture. After validating the methods in two sets of test patients with clearly identifiable atrial depolarization on surface ECG, one method was successfully applied to a patient in whom atrial depolarization could not be reliably ascertained on surface ECG. These methods promise to be useful in selected patients in whom confirmation of atrial capture would otherwise be difficult.

Animals↗
PubMed1998

[The influence of cumulative dexamethasone, promethazine and dextran 70 used as protection against intraperitoneal adhesions on selected parameters of humoral immunity in women operated on for infertility].

One of the most frequent reasons of the intraperitoneal adhesions formation in young women is pelvic inflammatory disease and surgical operations of pelvic organs. The element of more complex activities against adhesion creation is to limit an inflammatory reaction in the area of operation by intraperitoneal and systemic pharmacotherapy. The system of activities put into practice in the Clinic of Gynaecology includes in the field of pharmacological prophylaxis a systemic and intraperitoneal use of dexamethasone and promethazine before, during and after the operation, in total doses respectively: 250 mg and 300 mg, as well as intraperitoneal dosing of 500 ml of dextran 70, just before closing the peritoneal cavity. Verification of the results of these activities during laparoscopy or laparotomy shows its high effectiveness. For many years we did not observe any complications of any wound healing after the operations. Due to existing reports about possible complications in the postoperation period, which are probably caused by the use of the above-mentioned pharmaceutics, I decided to investigate how dexamethasone, promethazine and dextran 70 influence the selected parameters of humoral resistance in women who were operated on due to mechanical infertility. The investigated group consisted of 30 women, while the control group comprised 10 women who had gynaecological operations of similar extent. The venal blood samples were collected before the operation and on the third, fifth and twenty first day after the operation. The levels of selected acute phase proteins were checked and the character as well as the dynamics of value changes were monitored in both groups. Because of great variability between the proteins the fractions were picked out focusing on the differences in dynamics of metabolism, half-life time and biological functions. Following proteins were investigated: C-reactive protein, alfa1-acid glycoprotein, haptoglobin, alfa1-antitripsin, ceruloplazmin, alpha2-macroglobin, hemopexin, immunoglobulins A, G, M, albumins, transferrin, alpha2-HS-glycoprotein. The analysis of the study results has indicated that the application of dexamethasone, promethazine and dextran 70 only exerts modulating influence on the course of acute phase reaction induced by the operations. In the group having been studied earlier (in 3rd postoperative 24-hours) significant changes were revealed concerning the level of particular proteins in accordance with their physiological character (increase or decrease of level) in the control group such changes appeared later (about 5th 24-hours) and were characterized by markedly smaller amplitude and dynamics (Tab. 1-2, Fig. 1-15). The levels of proteins defined prior to operation were reached faster by patients of the study group (up to 21st 24-hours after operation). It has been disclosed that the use of composed antiadhesion therapy with dexamethasone, promethazine and dextran 70 accelerates, intensifies and simultaneously restricts the duration of transformations defined as acute phase reaction, which result in reducing the number of intraperitoneal adhesions. This therapy does not impair the mechanisms of humoral immunity in patients operated on.

Acute-Phase Reaction↗
PubMed1992

Main structural and functional features of the basic cytosolic bovine 21 kDa protein delineated through hydrophobic cluster analysis and molecular modelling.

A 21 kDa protein purified from bovine brain cytosol was previously described as a hydrophobic ligand binding protein; however, its accurate biological function remained still uncertain. In order to get further information about its potential biological role, an extended prediction of its secondary and three dimensional structures was undertaken. We describe here a process which permitted us to discover a structural homology between the 21 kDa protein and the N-domain of yeast phosphoglycerate kinase (PGK). This process is based on comparing the 21 kDa protein with all the proteins presenting a slight homology, by using the Hydrophobic Cluster Analysis (HCA) method. According to the observed similarity between the N-domain of yeast PGK and the 21 kDa protein, we built a model which was shown to possess a potential binding site for nucleotides. Moreover, the model obtained presents three-dimensional (3D) structure similarity with adenylate kinase. These results suggest two main hypotheses: (i) the 21 kDa protein may belong to the kinase family; (ii) the binding of a nucleotide could imply a modification of the 3D structure of the 21 kDa protein that can promote the transfer of hydrophobic ligands to the plasma membrane. Meanwhile, verification of these hypotheses has been in part performed experimentally: the 21 kDa protein binds MgATP as well as, to a lesser extent, phosphoglycerate.

Amino Acid Sequence↗
PubMed1994

Disposable adult breathing circuits for use with critical care ventilators.

In this issue, we evaluate seven models of disposable breathing circuits from seven manufacturers; the evaluated circuits are intended to be used for adult patients on critical care ventilators. This study is a follow-up to our earlier Evaluation of disposable breathing circuits for use with portable ventilators, published in Health Devices 22(7), July 1993. We based our ratings on the breathing circuits' ability to function properly with minimal intervention from the healthcare provider. We rated only one of the evaluated units Acceptable; this circuit was not likely to interrupt ventilation during normal use (provided that its operation was verified before use). Three of the evaluated breathing circuits were rated Unacceptable because they had disadvantages that were likely to interrupt ventilation during normal use (e.g., a component could accidentally disconnect, the tubing could become kinked or crushed). When such a disadvantage could be compensated for by the healthcare provider, we rated the circuit Conditionally Acceptable: one circuit was rated Conditionally Acceptable; two circuits that had other significant disadvantages were rated Conditionally Acceptable--Not Recommended. We caution readers not to base purchasing decisions on our ratings alone, but on a thorough understanding of the issues surrounding our conclusions, which can be gained by reading this study in its entirety. We offer additional guidance and discuss important selection factors and usage issues in the Selection and Use Guide for Disposable Breathing Circuits included at the end of the Evaluation. Also see "Pre-use Verification of Breathing Circuits" in this issue for step-by-step guidelines to help healthcare providers and caregivers verify proper performance and identify the defective circuits that inevitably reach the clinical setting.

Adult↗
PubMed2001

The accuracy of physical diagnostic tests for assessing meniscal lesions of the knee: a meta-analysis.

OBJECTIVE: Our systematic review summarizes the evidence about the accuracy of those tests. SEARCH STRATEGY: We performed a literature search of MEDLINE (1966-1999) and EMBASE (1988-1999) with additional reference tracking. SELECTION CRITERIA: Articles written in English, French, German, or Dutch, that addressed the accuracy of at least one physical diagnostic test for meniscus injury with arthrotomy, arthroscopy, or magnetic resonance imaging as the gold standard were included. We excluded studies if no reference group or only test-positives had been included, if the study pertained to cadavers only, or if only physical examination under anesthesia was considered. DATA COLLECTION/ANALYSIS: Two reviewers independently selected studies, assessed the methodologic quality, and abstracted data using a standardized protocol. We calculated sensitivity, specificity, and likelihood ratios for each test, and summary estimates when appropriate and possible. MAIN RESULTS: Of 402 identified studies, 13 met the inclusion criteria. The results of the index and reference tests were assessed independently (blindly) of each other in only 2 studies, and in all studies verification bias seemed to be present. The study results were highly heterogeneous The summary receiver operating characteristic curves of the assessment of joint effusion, the McMurray test and joint line tenderness indicated little discriminative power for these tests. Only the predictive value of a positive McMurray test was favorable. CONCLUSIONS: The methodologic quality of studies addressing the diagnostic accuracy of meniscal tests was poor, and the results were highly heterogeneous. The poor characteristics indicate that these tests are of little value for clinical practice.

Arthroscopy↗
PubMed1982

[The relationship between pre-operative emotional states and stress-linked parameters in surgical patients (author's transl)].

The relationship between the pre-operative emotional state and stress-linked endocrine, respiratory, metabolic and cardiovascular parameters was investigated. It could be demonstrated that the patients' affective state, especially anxiety, depression, feeling of debility, affected endocrine and metabolic function (concentration of serum cortisone and of serum free fatty acids respectively) as well as cardiovascular function, viz.: heart rate, systolic blood pressure and tension-time index. Subjects in a poor pre-operative state of mind showed statistically significant increases in serum cortisone levels and heart rate and also a higher tension-time index. Patients in a depressed state also had markedly higher heart rates immediately before the operation than had those who were in a cheerful confident mood. On the other hand the serum levels of free fatty acids, determined immediately before the operation, were higher in the latter than they were in patients who felt weak and debilitated. The observations are interpreted as the result of increased tone of the sympathetic nervous system in the presence of sthenic affects. The fact that these observations were made in patients undergoing the usual preparatory procedure prior to anaesthesia and surgery indicates that the routine preoperative preparations do not take sufficient account of the psychic and psychophysiological condition of the patient. Both the somatic and the emotional and psychophysiological responses should be considered in the preparation of the patient for surgery. Verification of the therapeutic success should include psychometric methods and measurement of stress-linked parameters.

Adult↗
PubMed2001

Identification of two estrogen regulated genes associated with growth regulation of human breast cancer.

We have identified two estrogen regulated gene products in the E(2) growth inhibited human breast cancer xenograft, T61; one showing 100% homology to the human BAC clone RP11-112E16, the other 100% homology to the human CPR3/DNJ3 gene. Verification by Northern blot analyses showed an up-regulation of the BAC clone RP11-112E16 and the CPR3/DNJ3 mRNAs upon E(2) treatment. Treatment of T61 tumors with tamoxifen, leading to static tumor growth, also increased the expression of the BAC clone RP11-112E16 and the CPR3/DNJ3 mRNAs. A similar association between growth inhibition and BAC clone RP11-112E16 and CPR3/DNJ3 mRNA induction was observed in MCF-7 cells treated with ICI 182.780. In MCF-7 cells, treatment with E(2) resulted in growth stimulation concomitant with a decrease in the BAC clone RP11-112E16 and CPR3/DNJ3 mRNA expression. Treatment with a combination of E(2) and ICI 182.780 abolished the anti-estrogen induced increase in BAC clone RP11-112E16 and CPR3/DNJ3 mRNA expression, indicating that regulation of the gene products is mediated through the ER. The association between growth inhibition and BAC clone RP11-112E16 or CPR3/DNJ3 mRNA expression was supported by high expression of both gene products in brain tissue. Further investigations are ongoing to clarify the biological function of these two gene products.

Animals↗
PubMed2005

Initiator tRNA binding by e/aIF5B, the eukaryotic/archaeal homologue of bacterial initiation factor IF2.

To carry initiator Met-tRNA(i)(Met) to the small ribosomal subunit, eukaryal and archaeal cells use a heterotrimeric factor called e/aIF2. These cells also possess a homologue of bacterial IF2 called e/aIF5B. Several results indicate that the mode of action of e/aIF5B resembles some function of bacterial IF2. The e/aIF5B factor promotes the joining of ribosomal subunits. Moreover, there is genetic evidence that the factor participates in the binding of initiator tRNA to the small ribosomal subunit. However, up to now, an interaction between e/aIF5B and initiator tRNA was not evidenced. In this study, we use an assay based on protection of aminoacyl-tRNA against spontaneous deacylation to demonstrate that archaeal aIF5B indeed can interact with initiator tRNA. In complex formation, aIF5B shows specificity toward the methionyl moiety of the ligand. The complex between Saccharomyces cerevisiae eIF5B and methionylated initiator tRNA is less stable than that formed with aIF5B. In addition, this complex is almost indifferent to the side chain of the esterified amino acid. These results support the idea that, beyond the channeling of Met-tRNA(i)(Met) to the 40S subunit by e/aIF2, e/aIF5B comes to interact with initiator tRNA on the ribosome. Recognition of an aminoacylated tRNA species at this site would then allow translation to begin. In the case of archaea, this checkpoint would also include the verification of the presence of a methionine at the P site.

Archaeal Proteins↗
PubMed1985

A model of proximal tubular bicarbonate absorption.

A model is presented that utilizes determinants of acidification defined from microperfusion studies in the rat to stimulate the effect on absolute bicarbonate absorption along the entire proximal convoluted tubule. Net bicarbonate absorption is considered to consist of active transcellular proton secretion in parallel with passive paracellular bicarbonate diffusion. The rate of proton secretion is calculated as a function of luminal bicarbonate concentration using Michaelis-Menten kinetics. The K1/2 is modified by luminal flow rate and the Vmax by peritubular bicarbonate concentration. Solute-solvent interactions and axial heterogeneity are also included as determinants of proton secretion rate. The model demonstrates that a given percentage stimulation or inhibition of active proton secretion leads to a much smaller effect on absolute proximal bicarbonate absorption along the entire tubular length. This blunting of the stimulation or inhibition is greatest when filtered bicarbonate load is limited by decreases in glomerular filtration rate or plasma bicarbonate concentration. In addition, the model shows that flow dependence is greater at low plasma bicarbonate concentrations, whereas the effect of extracellular fluid volume expansion is greater at high plasma bicarbonate concentrations. Agreement between the model predictions and the results of free-flow micropuncture studies from our laboratory is good with the exception of the effect of raising plasma bicarbonate concentration. This discrepancy is resolvable by allowing the effect of peritubular pH to increase along the length of the tubule, a hypothesis that requires verification.

Absorption↗
PubMed1999

Low yield of polymorphisms from EST blast searching: analysis of genes related to oxidative stress and verification of the P197L polymorphism in GPX1.

To determine new polymorphisms in the antioxidant enzymes superoxide dismutase, glutathione peroxidases, catalase, and microsomal glutathione transferase 1, a search of the human expressed sequence tags (EST) database was performed (with BLAST 2.0). When any mutation, indicated by the BLAST search, gave rise to a nonconservative amino acid change we performed polymerase chain reaction (PCR) restriction analysis and/or sequence analysis of genomic DNA from human subjects in order to verify these potential polymorphisms. Of nine indicated polymorphisms from the EST analysis found in four different antioxidant enzymes, we could verify one, an amino acid substitution Pro-Leu at amino acid position 197 (P197L), in the glutathione peroxidase 1 gene. The corresponding allele frequencies were approximately 70/30%. In addition, a silent mutation (1167T/C) in the catalase gene indicated by the BLAST search could also be verified. Six to nine individuals were analyzed per indicated polymorphism, so that only common polymorphisms would be found. The indicated mutations not verified by direct analysis thus cannot be excluded as allelic variation in the human population. These results show that the EST database can be used to search for polymorphisms in genes with high abundance in the human EST database. In addition to the EST analysis, PCR/single-strand conformation polymorphism (SSCP) was employed for the analysis of the microsomal glutathione transferase 1 gene. No polymorphism in the coding sequence could be detected in the gene by either method. The high degree of conservation of the microsomal glutathione transferase 1 gene indicates an important physiological function for this enzyme.

DNA Primers↗
PubMed2004

Controlling the effects of pulse transients and RF inhomogeneity in phase-modulated multiple-pulse sequences for homonuclear decoupling in solid-state proton NMR.

The effects of pulse imperfections and RF inhomogeneity on NMR spectra obtained with phase-modulated multiple-pulse NMR sequences are analyzed. The emphasis is on the combined effects of frequency offset, RF inhomogeneity, and pulse phase transients. To enable a theoretical description of the transients associated with phase changes under continuous RF irradiation, the nature of the transients is investigated in depth. As monitored in our 300 MHz spectrometer, they are found to be caused by linear elements of the RF circuitry. The validity of their representation as delta-function pulses and the significance of their decomposition into antisymmetric and symmetric components are discussed. A practical method for quantitative control of the antisymmetric phase transients is proposed. The linearity property allows the development of a theoretical description of the spin dynamics caused by the transients. This leads to a vector-Hamiltonian model for phase-modulated Lee-Goldburg experiments. It quantitatively predicts both the frequency shift and the line broadening caused by antisymmetric phase transients and their coupling with RF inhomogeneity. The model is shown to be equally applicable to frequency-switched Lee-Goldburg experiments. A noteworthy discovery is that for a given magnitude of the antisymmetric phase transients a frequency offset exists at which the inhomogeneity broadening is essentially canceled. This explains the common observation that for best resolution one side of resonance is preferred over the other. It also suggests a strategy for enhancing resolution without having to resort to severe sample volume restriction. Numerical calculations verified the theoretical predictions and allowed extension of the model to BLEW-12 and DUMBO-1. Experimental verification is presented. The deviations from theoretical predictions are discussed.

Journal Article↗
PubMed2007

Improved spontaneous erectile function in men with mild-to-moderate arteriogenic erectile dysfunction treated with a nightly dose of sildenafil for one year: a randomized trial.

AIM: To test the hypothesis that sildenafil (50 mg nightly for one year) can improve spontaneous erectile function (EF) in men with mild-to-moderate arteriogenic erectile dysfunction (ED) responsive to erectogenic treatment. METHODS: In a prospective open-label trial, 112 men with ED were randomized to sildenafil 50 mg nightly or sildenafil 50 or 100 mg as needed for 12 months, followed by one-month and 6-month non-medicated periods. Non-randomized, non-medicated men with ED were also assessed. The EF domain of the International Index of Erectile Function (IIEF EF) and the peak systolic velocity (PSV) of penile cavernous arteries were used to measure the efficacy. RESULTS: After sildenafil treatment and a subsequent non-medicated month, IIEF EF was normal in 29 of 48 (60.4%, 95% confidence interval [CI]: 45.3-74.2%) of the nightly group vs. 4 of 49 (8.2%, 95% CI: 2.3-19.6%) of the as-needed group. PSV improved by 11.2 cm/s (95% CI: 4.7-21.4; P=0.012) in the nightly group but only by 3.4 cm/s (-5.1-14.7; P=0.435) in the as-needed group. IIEF EF normalized in 1 of 18 (5.6%, 95% CI: 0.1-27.3%) non-medicated men and the PSV declined slightly. Six months after treatment, the IIEF EF remained normal and PSV was stabilized in most (28/29, 97%) nightly group men who had initially normalized. CONCLUSION: Sildenafil nightly for one year resulted in ED regression that persisted well beyond the end of treatment, so that spontaneous EF was characterized as normal on the IIEF in most men. The results from this open-label, randomized trial warrant verification under double-blind, placebo-controlled conditions.

Adult↗
PubMed2000

[Diagnosis of acute pyelonephritis in childhood: comparison of ultrasonographic examination and renal scintigraphy using 99mTc DMSA].

THE CURRENT STATE: Infections of the urinary tract are a frequent paediatric problem. Their treatment requires to assess the localisation of infection within the uropoetic tract. Especially the acute pyelonephritis (AP) can lead to irreversible changes within the renal parenchyma and alteration of renal functions. Some imaging examinations can help in the assessment of the diagnosis of AP and contribute to appropriate therapy. SUBJECTIVE: The analysis of results gained from imaging examinations in children with AP was based on the comparison of used techniques and the assessment of their exploitation for the diagnosis of AP. METHODS AND MATERIAL: 38 children (17 girls and 21 boys at average age of 11.6 years) with clinical criteria of AP were subdued to ultrasonographic examination with B record (US-B) and ultrasonographic examination with energetic Doppler (US-D). Both methods were compared with the findings gained by use of renal scintigraphy 99mTc DMSA. RESULTS: The positive finding of AP was proved in 36 children (94.7%). The results of US-B proved AP in 14 children (36.8%) of the whole group of patients, i.e. in 38.8% with positive DMSA finding. US-D changes indicated AP in 15 children (39.4%) of the whole group, i.e. in 41.6% with positive DMSA finding. The sensitivity of both methods US-B and US-D appear to be low for the verification of changes in renal parenchyma in AP. CONCLUSION: Despite its advantages and availability, the gain from ultrasonographic examination in children suffering from AP is small. Clinical and laboratory criteria are fully sufficient for AP verification in common clinical practice. DMSA scintigraphy is a method of choice in complicated cases of AP. (Tab. 1, Ref. 17.)

Acute Disease↗