bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased soluble CD14 in bronchoalveolar lavage fluid of stable lung transplant recipients
Authors: Ward C. , Walters E.H. , Zheng L. , Whitford H. , Williams T.J. , Snell G.I.
Published: July 2002

Macrophages, neutrophils and infection have been implicated in the genesis of the bronchiolitis obliterans syndrome (BOS) post lung transplantation. sCD14 is a soluble form of a shed-cell surface protein. It is capable of promoting cytokine-induced inflammation and it's presence in clinically stable lung transplant recipients (LTR) might be important as an early marker of BOS.

Bronchalveolar lavage (BAL) and blood samples were taken from 26 stable LTR, at or near their best forced expiratory volume in one second who were free from infection. sCD14 levels were measuredviaenzyme-linked immunosorbent assay. Cell counts were performed on unfiltered BAL.

LTR neutrophil count, BAL sCD14 and serum sCD14 levels were higher than controls (median 3.8%versus1.3%, p<0.05; 11.5 ng·mL−1versus6 ng·mL−1, p<0.001; 6.2 µg·mL−1versus2.4 µg·mL−1, p<0.05, respectively). BAL albumin and sCD14 correlated (regression coefficient: 0.77, p<0.001).

In this hypothesis-generating, cross-sectional study, the authors have described for the first time soluble CD14 levels in the bronchoalveolar lavage and serum of stable lung transplant recipients, and show that these are elevated compared to controls. This is a practicable candidate marker system, which can be tested for a predictive role in bronchiolitis obliterans syndrome following lung transplantation. The origin of this cellular protein and its temporal relationship to the development of the bronchiolitis obliterans syndrome remains to be elucidated in more definitive longitudinal studies, which should include other measurements potentially relevant to the innate immune system, such as bronchoalveolar lavage endotoxin levels.
Mechanisms and markers of airway inflammation in cystic fibrosis: Fig. 1.—
Authors: De Rose V.
Published: July 2002

Airway inflammation is now recognized as a major factor in the pathogenesis of lung disease in cystic fibrosis (CF). Its most characteristic feature is a marked and persistent influx into the airways of neutrophils, which damage the lung by releasing noxious mediators, such as reactive oxygen species and proteolytic enzymes.

Recent studies suggest that inflammation occurs very early and may even happen in the absence of infection. Furthermore, links between CF transmembrane conductance regulator dysfunction and both infection and inflammation are postulated; dysregulation of cytokine production and abnormal epithelial host defences have been regarded as causes of sustained inflammation.

Bronchoalveolar lavage and the evaluation of neutrophils and inflammatory mediators provide the most accurate picture of airway inflammation. Routine bronchoscopy with bronchoalveolar lavage, however, is unpleasant for the patient and usually is of no immediate benefit to the management of individual cases.

Therefore, surrogate markers collected by noninvasive procedures would be of great assistance in the follow-up of cystic fibrosis patients. Several markers have been evaluated in the sputum, serum and urine of cystic fibrosis patients and related to the degree of airway inflammation. Long-term studies are needed to confirm their potential clinical utility and specificity, and to determine which can be used clinically to monitor disease outcome and efficacy of treatment.
Effect of chest wall vibration on the canine diaphragm during breathing
Authors: Leduc D. , De Troyer A.
Published: July 2002

High-frequency mechanical vibration of the ribcage reduces dyspnoea in patients with chronic obstructive pulmonary disease, and the suggestion has been made that this effect might be related to a decrease in central respiratory drive resulting from an increase in afferent inputs from intercostal muscles. In the present studies, the effects of ribcage vibration on central respiratory drive have been assessed without the confounding influence of conscious reactions.

The electromyographic (EMG) activity of the diaphragm and the changes in pleural (Ppl) and abdominal (Pab) pressure were measured in six anaesthetized, spontaneously-breathing dogs while the rostral, the middle, or the caudal portion of the ribcage was vibrated at intervals during inspiration. The EMG activity of the external and parasternal intercostals was also measured.

Ribcage vibration consistently elicited a marked increase in the inspiratory EMG activity recorded from the external intercostals, thus indicating that the procedure did activate intercostal muscle spindles. However, no alteration in diaphragmatic or parasternal intercostal EMG activity was seen in any animal. Transdiaphragmatic pressure and the relationship between ΔPaband ΔPplduring inspiration were also unaltered.

The authors conclude that ribcage vibration and, with it, stimulation of external intercostal muscle spindles has no significant influence on phrenic motoneurones or on medullary inspiratory neurones. It is unlikely, therefore, that the beneficial effect of the procedure on dyspnoea results from a specific reduction in central respiratory drive.
Characterization of pulmonary vascular remodelling in smokers and patients with mild COPD
Authors: Santos S. , Peinado V.I. , Ramírez J. , Melgosa T. , Roca J. , Rodriguez-Roisin R. , Barberà J.A.
Published: July 2002

Intimal enlargement of pulmonary arteries is an early change in chronic obstructive pulmonary disease (COPD). The cellular and extracellular components that are involved in this enlargement are unknown. The present study was designed to characterize the structural changes occurring in pulmonary muscular arteries in the initial disease stages.

Lung specimens from patients with moderate COPD (n=8; forced expiratory volume in one second (FEV1), 66±10% predicted) and smokers without airflow obstruction (n=7; FEV1, 86±6% pred), were investigated by histochemistry to characterize extracellular matrix proteins and by immunohistochemistry to identify intrinsic cells of the vascular wall.

In both COPD patients and smokers, the majority of cells present in the enlarged intimas were stained by specific smooth muscle cell (SMC) markers. No staining with endothelial or fibroblast markers was shown. A proportion of SMCs did not stain with desmin, suggesting cellular heterogeneity in this population. Elastin was the most abundant extracellular matrix protein and collagen was seen in a lower proportion. The amount of collagen was related to the intimal thickness (p<0.001).

The findings demonstrated smooth muscle cell proliferation, as well as elastin and collagen deposition, in the thickened intimas of pulmonary arteries in moderate chronic obstructive pulmonary disease patients and smokers, suggesting that these abnormalities may originate at an early stage in cigarette smoke-induced respiratory disease.
Free, soluble interleukin-17 protein during severe inflammation in human airways
Authors: Laan M. , Palmberg L. , Larsson K. , Lindén A.
Published: July 2002

Studies in rodents indicate that the cytokine, interleukin (IL)-17, links the activation of T-lymphocytes to neutrophilic inflammation. The aim of the current study was to determine whether free, soluble IL-17 protein can be released during severe inflammation in human airways.

Fifteen healthy subjects were exposed to a swine confinement in order to induce severe inflammation characterized by high neutrophil numbers in the airways. Bronchoalveolar lavage (BAL) fluid was harvested 2 weeks prior to and 24 h after this exposure and the concentration of IL-17 protein was measured using an enzyme-linked immunosorbent assay. Total and cell differential counts were also performed in BAL fluid.

Prior to exposure to the swine confinement, the concentration of IL-17 in BAL fluid was low (<7.8 pg·mL−1) in 14 out of 15 subjects. However, exposure to the swine confinement caused an increase in IL-17 in 13 out of 15 subjects (median IL-17 concentration of 26.9 pg·mL−1). This exposure also caused a 51-fold increase in the concentration of neutrophils in BAL fluid.

To conclude, free, soluble interleukin-17 protein can be released during severe inflammation characterized by high neutrophil numbers in human airways. The significance of interleukin-17 in inflammatory airway diseases therefore deserves further evaluation.
Effects of lung volume reduction surgery in hamsters with elastase-induced emphysema
Authors: Marchand E. , De Leyn P. , Gayan-Ramirez G. , Palecek F. , Verbeken E. , Decramer M.
Published: July 2002

Lung volume reduction surgery (LVRS) has been shown to improve respiratory mechanics in selected patients with severe emphysema. This is thought to be due to an improvement in lung elastic recoil. This study was aimed at gaining further understanding about the effects of LVRS on respiratory mechanics and airway function.

Control hamsters instilled with saline (Ctrl; n=8) were compared with emphysematous animals that underwent either a sham operation (Sham; n=7) or an LVRS (LVRS; n=7).

As expected, there was a significant increase in the static lung volumes in the Sham as compared to the Ctrl group and a significant decrease of these volumes in LVRS as compared to the Sham group. Surprisingly, emphysema was associated with a significant increase and LVRS with a significant decrease in vital capacity. Despite a tendency toward an increase in lung compliance as compared to Sham, indices of maximal expiratory flows tended to decrease with LVRS. As opposed to humans, there was no change in the distribution of airway diameters in Sham compared to Ctrl.

These findings appear to be largely explained by the high compliance of the hamster chest wall. This allows for better matching between the emphysematous lung and the chest-wall sizes than in humans.
Airway inflammation and bronchial microbial patterns in patients with stable chronic obstructive pulmonary disease
Authors: Soler N , Ewig S , Torres A , Filella X , Gonzalez J , Zaubet A
Published: July 2002

The effect of bacterial colonization of the bronchi on the progress of airflow limitation is not well known. Therefore, the pattern of airway inflammation in smokers and patients with stable chronic obstructive pulmonary disease (COPD) and its relation to bronchial microbial colonization was assessed. Eight nonsmoking and 18 smoking controls as well as 52 patients with COPD (28 mild, 11 moderate and 13 severe) were studied. All subjects were investigated by means of flexible bronchoscopy including protected specimen brush and bronchoalveolar lavage (BAL) sampling. Differential cell counts, cytokine (interleukin (IL)-1beta, IL-6, IL-8, IL-10 and tumour necrosis factor-alpha(TNF-alpha) concentrations and microbial patterns were determined in BAL fluid. Forced expiratory volume in one second (FEV1) % of the predicted value was inversely correlated with pack-yrs of cigarette smoking (r=-0.47, p<0.0001), the percentage of neutrophil (p=-0.56, p<0.0001) and IL-6 (p=-0.37, p=0.01) and IL-8 concentration (p=-0.43, p=0.004) in BAL fluid. Accordingly, pk-yrs of cigarette smoking (p=0.39, p=0.01) and IL-8 (p=0.69, p<0.0001) and TNFalpha (p=0.4, p<0.005) were positively correlated with the percentage of neutrophils in BAL fluid. Smoking controls and COPD patients were mainly colonized in the bronchial tree (33%) by community endogenous potentially pathogenic micro-organisms (PPMs). Colonization rates and patterns of PPMs were not affected by severity of airflow obstruction. The presence of PPMs was significantly associated with higher percentages of neutrophils (33.2+/-10.4% versus 10.1+/-3.5%, p=0.02) and TNF-alpha concentration (29.9+/-10.8 versus 6.3+/-2.1 pg x mL(-1), p=0.01) in BAL fluid. In conclusion, bronchial neutrophilia is a key inflammatory pattern in chronic obstructive pulmonary disease patients. Bronchial colonization with potentially pathogenic micro-organisms may represent an independent stimulus for additional airway inflammation.
Asthma quality of life during 1 year of treatment with budesonide with or without formoterol
Authors: Juniper EF , Svensson K , O'Byrne PM , Barnes PJ , Bauer CA , Lofdahl CG , Postma DS , Pauwels RA , Tattersfield AE , Ullman A
Published: July 2002

The Formoterol and Corticosteroids Establishing Therapy (FACET) study has provided the first opportunity to examine the long-term effects of inhaled steroids and long-acting beta2-agonists on asthma-specific quality of life. The objectives of the present study were to: evaluate the effects of long-term (1 yr) formoterol and increasing doses of budesonide on asthma quality of life; 2) to determine whether initial improvements in quality of life are sustained when improvements in clinical indices persist; and 3) to evaluate the long-term relationship between changes in clinical indices and changes in quality of life. Of the 852 asthmatic adults enrolled, 470 from five countries participated in this quality of life evaluation. After a 4-week run-in on 1,600 microg budesonide, patients were randomized to either 200 microg (Bud200) or 800 microg budesonide (Bud800) in combination with either 24 microg formoterol (F) or placebo daily for 1 yr. The Asthma Quality of Life Questionnaire (AQLQ) was completed and conventional clinical indices measured at enrolment and randomization and on seven occasions during the following 12 months. During the run-in, there was an improvement in AQLQ score (changes (delta) in overall score approximately 0.50; p<0.0001). After randomization, there was a further improvement in the Bud800+F group (delta=0.21; p=0.028). One month post-randomization, improvements in all groups stabilized and were sustained throughout the 12 months in a pattern very similar to that observed for the conventional clinical indices. The correlation of individual patient changes in clinical indices and changes in AQLQ score during the 12-month randomized period were weak to moderate (maximum r=0.51). Improvements in quality of life, which were greatest in the 800 microg budesonide plus 24 microg formoterol group, were sustained throughout the 12 months in a similar manner to the clinical indices. Long-term changes in conventional clinical indices cannot be used to predict the effect of treatment on individual patient experience.
A new questionnaire for the repeat of the first stage of the European Community Respiratory Health Survey: a pilot study
Authors: de Marco R , Zanolin ME , Accordini S , Signorelli D , Marinoni A , Bugiani M , Lo Cascio V , Woods R , Burney P
Published: July 2002

In the early 1990s a multicentre survey on asthma was performed on the young adult population (European Community Respiratory Health Survey - ECRHS). This study is to be repeated in order to estimate changes in the prevalence of asthma-like symptoms during the last decade and to assess the social and economic costs of the disease and their variations among countries. The self-administered questionnaire devised for this purpose is a two-page questionnaire. The first page contains the same items as those used in the first survey with four additional questions related to: 1) the frequency and severity of asthma attacks; 2) the presence of chronic bronchitis; 3) smoking habits; and 4) a visual analogue scale assessing perception of outdoor pollution. The second page aims to collect information regarding the direct and indirect costs of asthma. The influence of the length of the questionnaire on the response rate was assessed in a pilot study in Italy. Two random samples of 150 subjects received either the one-page questionnaire (first page) or the two-page questionnaire. The response rate was compared with that obtained from the first postal wave in the 1991-1992 survey. Although the response rate was unchanged when using the one-page questionnaire (45% versus 45%), it decreased by 7% when the two-page questionnaire was used (38% versus 45%). On the basis of these results, no problem should arise if four more questions are added to the one-page questionnaire. The slight reduction in the response rate of the two-page questionnaire is worrying but could be corrected by the use of telephone interviews.
Reduction in bronchodilation following a deep inhalation is poorly related to airway inflammation in asthma
Authors: Pacini F , Filippelli M , Duranti R , Rosi E , Romagnoli I , Grazzini M , Stendardi L , Misuri G , Scano G
Published: July 2002

In patients with bronchial asthma, forced expiratory flows are differently sensitive to a previous volume history. A reduced ability of a deep inhalation (DI) to dilate obstructed airways has been hypothesized to be a physiological marker for the degree of airway responsiveness and to relate to the presence and magnitude of inflammation in the lung, even in mild stable asthma. However, there are at present doubts as to whether functional changes could be used as a substitute for airway inflammation studies. In order to investigate the interrelations among airway inflammation, bronchial hyperresponsiveness and effects of volume history, 58 consecutive asthmatics with mild to moderate asthma were studied. The effects of DI were assessed as the isovolumic ratio of flows from forced expiratory manoeuvres started from maximal (M) or partial (P) lung inflation. Airway inflammation was assessed by using induced sputum. Sputum was analysed for total and differential cell counts, and levels of eosinophil cationic protein (ECP) which reflects eosinophil activation. Airway responsiveness was assessed as the provocative concentration of histamine which caused a 20% fall in forced expiratory volume in one second (FEV1) from control (PC20). The M/P ratio was significantly related to ECP (r=-0.31, p<0.03) and eosinophils (r=-0.29, p<0.03), FEV1/vital capacity (VC) (r=0.32; p<0.01), clinical score (r=-0.33; p<0.03) and age (r=-0.41; p<0.0001). In a stepwise multiple regression analysis including age, score, baseline lung function, ECP, number of eosinophils and the response to beta2-agonist, age (p<0.037) predicted a small amount of the variance in M/P ratio (r2=0.12). It is concluded that volume history response is substantially independent of both sputum outcomes (inflammatory cell number and eosinophil cationic protein) and bronchial hyperresponsiveness; rather it seems to be associated with anthropometric characteristics. Functional aspects do not provide information on eosinophilic, probably central, airway inflammation.
Treatment of chronic sarcoidosis with an azathioprine/prednisolone regimen
Authors: Muller-Quernheim J , Kienast K , Held M , Pfeifer S , Costabel U
Published: July 2002

In a few patients with chronic sarcoidosis, prolonged, unacceptably high doses of corticosteroids are required to achieve symptomatic relief. In these cases, a corticosteroid-sparing drug might be administered to allow long-term treatment without the adverse effects of corticosteroids. This study examines azathioprine as a prednisolone-sparing treatment. In an open study, the course of 11 patients with chronic sarcoidosis was analysed. In an induction phase, 2 mg azathioprine x kg body weight (BW)(-1) x day(-1) in combination with 0.6-0.8 mg prednisolone x kg BW(-1) x day(-1) were administered with prednisolone being reduced to 0.1 mg x kg BW(-1) x day(-1) within 2-3 months. This was followed by a 21-22-month maintenance phase with 2 mg azathioprine x kg BW(-1) x day(-1) and 0.1 mg prednisolone x kg BW(-1) day(-1). Clinical parameters and immunological findings of bronchoalveolar lavage (BAL) were analysed. All patients had significant symptomatic relief and improvements or resolutions of physiological, serological and radiographic findings without suffering from serious adverse effects. Nine of 11 patients completed therapy after 19-26 months, and 2/11 patients terminated therapy after 8 and 12 months, respectively. Eight patients had remissions lasting 4-73 months. Three relapses occurred after 8, 18, and 22 months. During the induction phase, BAL cell composition changed and their activity in terms of cytokine release was suppressed. This preliminary study suggests that azathioprine may be effective as a corticosteroid-sparing agent in long-term therapy of sarcoidosis, but a much larger study is necessary to give the definitive answer.
In vitro investigations of jet-pulses for the measurement of respiratory impedance in newborns
Authors: Schmidt M , Foitzik B , Hochmuth O , Schmalisch G
Published: July 2002

The aim of this in vitro study was to investigate the measuring range and accuracy of a miniaturized equipment for respiratory impedance (Zrs) measurements in newborns using jet-pulses. Brief flow pulses (peak flow=16 L x min(-1), width=10 ms) were generated by a jet-generator consisting of a solenoid valve and an injector, situated between pneumotachograph and outflow resistance. Serially arranged resistance-inertance-compliance (R-I-C) lung models (RM=1.3-6.4 kPa x L(-1) x s, CM=7.4-36.9 mL x kPa(-1), IM=1.5 Pa x L(-1) x s2) were used to measure the real and imaginary part of Zrs between 4 and 50 Hz and to determine R, C and I by means of the method of least squares. The median errors for R, C and I were -0.1 kPa x L(-1) x s (-2%), 2.4 mL x kPa(-1)(13%) and -0.2 Pa x L(-1) x s2 (-13%) for measurements without breathing signals and 0.11 kPa x L(-1) -s (3%), 3 mL x kPa(-1) (16%) and 0.28 Pa x L (-1) x s2 (19%) in mechanically ventilated models. During spontaneous breathing the influence of the breathing flow on Zrs was negligible. The equipment did not show any nonlinearity when different pulse amplitudes were used (Vmax=13-22 L x min(-1)). The investigations have shown that jet-pulses allow reliable measurements of respiratory impedance and have the potential to provide valuable information about lung mechanics in spontaneously breathing and mechanically ventilated newborns. The developed measuring head has a low apparatus dead space, is easy to disinfect, has standard connections and can be used as the T-piece in a ventilator circuit.
A simple new technique to measure the effective dead space of the face mask with a water volumeter in infants
Authors: Morris MG
Published: July 2002

Measuring the effective dead space (EDS) of a face mask has been difficult in infants and the appropriate volume being deducted from lung volume measurements has varied between laboratories. This study measured EDS in 16 infants (age range, 5-36 months) who have cystic fibrosis, undergoing lung volume measurement by N2 washout. A thin plastic bladder, whose neck resided in the mask port, was shaped to fill a size 1 clear face mask. A water volumeter was made by inserting the body of a 20 mL plastic syringe into the neck of the bladder forming a tight seal with a snug fit against the inner surface of the mask port. The mask was placed on a horizontal surface and water was added until a level appeared in the syringe body (V1). At end-inspiration, the mask was briefly placed on the mouth and nose of the sleeping infant, causing the water level to rise in the syringe body (V2). The actual total dead space (V) of the mask when connected to the mouth port of the slide valve was 23 mL. EDS = V- (V2 - V1). Mean (95% confidence interval (95%CI)) EDS was 12.4 (95% CI 11.2, 13.6) mL. The smallest EDS was 8 mL since the connected ports (dead space, 8 mL) were unlikely to be penetrated by the infant's nose or lips. EDS decreased with increasing body weight and height, but seemed to be influenced by individual facial features too. In conclusion, a reliable noninvasive volumetric technique for the routine measurement of the effective dead space in infants has been developed.
Assessment of a simple scoring system applied to a screening questionnaire of asthma in children aged 5-15 yrs
Authors: Frank TL , Frank PI , McNamee R , Wright T , Hannaford P , Morrison J , Hirsch S , Pickering CA
Published: July 2002

The aim of the present study was to validate a simple scoring system using a parent-completed screening questionnaire to identify children aged 5-15 yrs who may have asthma. A stratified random sample of 157 children of 1,808 whose parents had answered a postal respiratory questionnaire underwent detailed clinical evaluation. The results were reviewed by three independent paediatricians whose opinions were combined to reach, for each child, decisions regarding three standards: 1) "possible asthma" defined as >50% likelihood of having asthma; 2) "possible asthma" defined as meriting a clinical trial of asthma medication; and 3) "probable asthma" defined as >90% likelihood of having asthma. The combined decisions were compared to three sets of questionnaire scores, in order to determine the positive predictive value, sensitivity and specificity of each set in identifying children with probable/possible asthma. The three sets of chosen questionnaire scores all had positive predictive values of 79-96% for predicting possible asthma, using either the combined expert opinion ">50% likelihood of asthma" or that of "warrants a trial of treatment" as the definition. This suggests that a low proportion of false positives would be obtained were this scoring system to be used for a screening programme. The combined decision >90% chance of asthma could be used as a means of estimating prevalence of asthma in the survey. When used for this, the prevalence of asthma in the surveyed population was 18.8% (95% confidence interval 13.1-26.3). In conclusion, the present scoring system, based on a simple respiratory questionnaire, provides a valid method of identifying children likely to have asthma, and who, if unknown to the medical services, would benefit from clinical review.
A comparative study on the efficacy of levofloxacin and ceftazidime in acute exacerbation of bronchiectasis
Authors: Tsang KW , Chan WM , Ho PL , Chan K , Lam WK , Ip MS
Published: July 2002

A prospective randomized study was performed in order to compare the efficacy of oral levofloxacin, a new S- isomer of ofloxacin, with intravenous ceftazidime in the empirical treatment of acute exacerbations of bronchiectasis. Consecutive patients with acute exacerbation of bronchiectasis were recruited at a tertiary referral centre and were randomized to receive 10 days' treatment with either oral levofloxacin (300 mg b..d.) or ceftazidime (1 g i.v.t.d.). Body temperature, cough score, dyspnoea score, sputum purulence and volume and white blood cell and neutrophil count were assessed on day 1 and day 10. Thirty-five patients (mean age 61 yrs, 15 males) completed the study; 17 of these were in the levofloxacin group. There was no significant difference in the distribution of sputum pathogens or clinical parameters between the two groups at entry to and completion of the study. Both groups of patients showed significant improvement in 24-h sputum volume, sputum purulence score, cough score and dyspnoea score (p<0.001) but there was no significant difference between these two groups at entry to or on completion of the study (p>0.05). The results of this study suggest that oral administration of levofloxacin is as effective as parenteral ceftazidime in the empirical treatment of exacerbations in bronchiectasis.
Development of irreversible airflow obstruction in a patient with eosinophilic bronchitis without asthma
Authors: Brightling CE , Woltmann G , Wardlaw AJ , Pavord ID
Published: July 2002

Eosinophilic bronchitis is a recently described condition presenting with chronic cough and sputum eosinophilia without the abnormalities of airway function seen in asthma. The patient, a 48-yr-old male who had never smoked, presented with an isolated chronic cough. He had normal spirometric values, peak flow variability and airway responsiveness, but an induced sputum eosinophil count of 33% (normal <1%). Although his cough improved with inhaled corticosteroids the sputum eosinophilia persisted. Over 2 yrs he developed airflow obstruction, which did not improve following nebulized bronchodilators and a 2-week course of prednisolone 30 mg once daily sufficient to return the sputum eosinophilia to normal (0.5%). It is suggested that the progressive irreversible airflow obstruction was due to persistent structural change to the airway secondary to eosinophilic airway inflammation, and it is further speculated that eosinophilic bronchitis may be a prelude to chronic obstructive pulmonary disease in some patients.
Multicomponent AVO analysis, Vacuum field, New Mexico
Authors: DeVault Bryan , Davis Thomas L. , Tsvankin Ilya , Verm Richard , Hilterman Fred
Published: July 2002

Shear‐wave amplitude variation with offset (AVO) analysis can be used to map changes in density, shear‐wave velocity, and fracturing at reservoir scale by allowing the influence of each factor to be separately extracted from the observed seismic response. Weighted least‐squares inversion of the anisotropic reflection coefficients was implemented to find the shear‐wave splitting coefficient and velocity‐contrast parameters. A time‐lapse nine‐component, 4‐D seismic survey acquired over Vacuum field in Lea County, New Mexico, was used to test our methodology of shear‐wave AVO analysis and to compare the results with well production and azimuthal P‐wave AVO analysis.

Weighted least‐squares shear‐wave AVO stacks of the splitting parameter were found to be excellent predictors of well fluid‐production performance, implying a strong link between seismically inferred fracturing and reservoir‐scale permeability of the San Andres dolomites at Vacuum field. Analysis of the shear‐wave velocity contrast indicated the presence of a second set of open fractures to the south of a carbon dioxide injector well where a 4‐D anomaly associated with injection had been observed.
Practical applications of uniqueness theorems in gravimetry: Part I—Constructing sound interpretation methods
Authors: Silva João B. C. , Medeiros Walter E. , Barbosa Valéria C. F.
Published: July 2002

To obtain a unique and stable solution to the gravity inverse problem, a priori information reflecting geological attributes of the gravity source must be used. Mathematical conditions to obtain stable solutions are established in Tikhonov's regularization method, where the a priori information is introduced via a stabilizing functional, which may be suitably designed to incorporate some relevant geological information. However, there is no unifying approach establishing general uniqueness conditions for a gravity inverse problem. Rather, there are many theorems, usually establishing just abstract mathematical conditions and making it difficult to devise the type of geological information needed to guarantee a unique solution.

In Part I of these companion papers, we show that translating the mathematical uniqueness conditions into geological constraints is an important step not only in establishing the type of geological setting where a particular method may be applied but also in designing new gravity inversion methods. As an example, we analyze three uniqueness theorems in gravimetry restricted to the class of homogeneous bodies with known density and show that the uniqueness conditions established by them are more probably met if the solution is constrained to be a compact body without curled protrusions at their borders. These conditions, together with stabilizing conditions (assuming a simple shape for the source), form a guideline to construct sound gravity inversion methods. A historical review of the gravity interpretation methods shows that several methods implicitly follow this guideline.

In Part II we use synthetic examples to illustrate the theoretical results derived in Part I. We also illustrate that the presented guideline is not the only way to design sound inversion methods for the class of homogeneous bodies. We present an alternative approach which produces good results but whose design requires a good dose of the interpreter's art.
Identification of subsonicP‐waves
Authors: Michaels Paul
Published: July 2002

A field trial was conducted to test the existence of subsonic (Vp< 331 m/s) P‐waves previously reported in the literature. A 1‐m‐long reverse profile was acquired with three‐component (3C) geophones on a sandy silt (unified classification ML). The silt had a porosity of 54%, a degree of water saturation of 63%, and a plasticity index of 10. No subsonic P‐waves were observed, although high‐frequency (up to 1200 Hz) Rayleigh waves were identified by hodogram analysis. These surface waves were observed with horizontal velocities that varied from 40 to 200 m/s. Hodogram observations and theory suggest that a portion of the data were also in the near‐field.
Metalliferous mining geophysics—State of the art in the last decade of the 20th century and the beginning of the new millennium
Authors: Nabighian Misac N. , Asten Michael W.
Published: July 2002

The downturn in mining activity experienced during the 1990s did not preclude significant new developments in various areas of mining geophysics. The methodology for acquiring and compiling data has kept pace with the latest technological developments, from Global Positioning System navigation to raster displays and parallel computing. Wavelet transforms, principal component analysis, and fractals have begun to find successful applications in both processing and interpretation of geophysical data. Methods of quantitatively interpreting/inverting anomalies in terms of 2‐D and 3‐D models of causative bodies are becoming common.

For the first time it is possible to make airborne gravity gradient measurements suitable for use in mineral exploration. Lower transmitter frequencies for airborne time‐domain electromagnetic (EM) systems have enabled surveys in areas where conductive cover previously screened basement conductors. The use of approximation algorithms has allowed the transformation of either time‐domain or frequency‐domain data into conductivity‐depth images (CDIs) which expedite interpretation. Full‐waveform recording and the use of multiple receivers are becoming common for ground EM techniques.

In radiometrics it is now common practice to record 256 channels of spectral data which, by using statistical methods, has led to a dramatic reduction of noise in aerial gamma‐ray surveys. Finally, advances in 3‐D oil‐field seismic reflection methods have been introduced into the search for mineral deposits, thereby providing new tools for studying the environment of orebody emplacement as well as detailed geometrical information of value for both exploration and mine‐planning applications.

Thus, at the beginning of the 21st century, we find the geophysical techniques used by the mining industry to be at the forefront of the latest technological developments.
Hemocompatibility of a coaxial pump catheter for less invasive heart surgery
Authors: Mueller Xavier M , Augstburger Monique , Boone Yves , von Segesser Ludwig K
Published: July 2002

Off-pump coronary artery bypass (OPCAB) requires heart manipulation during exposure of the lateral and posterior walls of the heart, which may cause hemodynamic instability, mainly through right ventricular dysfunction. A coaxial atrial cannula connected to a minicentrifugal pump was developed to bypass the right heart. This study was designed to test the hemocompatibility of this pump ongoing for 6 h. In five calves (bodyweight, 70.3± 4.2 kg), the pump was inserted and set to its maximal motor speed of 7000 rpm. Blood samples were taken for blood gas analyses, hematology and chemistry on an hourly basis. ANOVA was used for statistical analysis. During the 6-h run, hematocrit and red blood cell count were stable ( p= 0.77 and 0.87, respectively). Platelet count was not significantly altered ( p= 0.55). LDH was stable ( p= 0.61) and plasma free hemoglobin remained below 100 mg/l throughout the experiment. Adequate tissue perfusion was maintained as reflected by the stable mixed venous oxygen saturation (baseline, 72.5± 2%, and 6 h, 65.6± 3.4%) and no defect of any pump system was detected during this 6-h testing. This right heart minipump appears to have a minimal impact on red cells and platelets when set at its maximal speed for 6 h, underlining the hematological safety of the system.
Radiation-induced brachial plexopathy in women treated for carcinoma of the breast
Authors: Fathers Edward , Thrush David , Huson Susan M , Norman Andrew
Published: July 2002

Objectives: To study the clinical presentation and natural history of radiationinduced brachial plexopathy in 33 women treated for carcinoma of the breast.

Methods: All of the patients were referred to a single consultant neurologist. Details of surgical procedures, radiotherapy, symptoms at presentation and follow-up and neurological ”ndings were recorded. Patients were reviewed at six or 12 monthly intervals for 2–19 years (median 9.5 years). Investigations included blood tests, chest X-ray, bone scan, neurophysiological studies, computerized tomography (CT) or magnetic resonance imaging (MRI) of the cervical spine and cerebrospinal ‘uid examination.

Results: Symptoms began from six months to 20 years after radiotherapy (median time 1.5 years). Progressive weakness was universal and resulted in loss of any useful hand function in all but three patients. The time taken to loss of useful hand function ranged from six weeks to ”ve years (median 1.25 years). Three patterns of upper limb weakness were identi”ed, distal limb weakness only (13 patients), global limb weakness that was more marked distally (11 patients), and completely ‘accid arm (10 patients). Seventeen patients required long-term morphine to palliate pain. A chemical sympathectomy beneted three patients.

Conclusions: Most patients developed symptoms within three years, but late presentations 8–20 years later were encountered. Symptoms were progressive in all patients, though the rate did vary. Pain was common and persisted inde”nitely in all but one patient. Morphine was effective and should be used early and in adequate doses. Chemical sympathectomy provided sustained relief in three of six patients.
Functional gain of hip fracture patients in different cognitive and functional groups
Authors: Beloosesky Yichayaou , Grinblat Josef , Epelboym Boris , Weiss Avraham , Grosman Boris , Hendel David
Published: July 2002

Objective: To follow up six months post hip fracture and to compare functional gain of patients in different cognitive and functional groups.

Design: Prospective longitudinal study of hip fracture patients with functional evaluation pre-fracture, prior to discharge from orthopaedic department and one, three and six months post fracture.

Setting: Department of Orthopaedics, Rabin Medical Center, Golda Campus with follow-up at Beit-Rivka Geriatric Rehabilitation Hospital, both in Petach Tikvah, Israel, with a minority of patients followed at home or nursing home.

Measurement: Cognition evaluated by Mini-Mental State Examination, prefracture functioning by Functional Independence Measure and Katz Index of ADL. Functional outcome assessed by Functional Independence Measure gain defined as the difference between Functional Independence Measure scores at six months and just prior to discharge from the Department of Orthopaedics.

Results: Moderately cognitively impaired and normal patients had the same Functional Independence Measure – A (self-care) and Functional Independence Measure – B (motor) gains. Pre-fracture independent patients had significantly higher Functional Independence Measure – A and Functional Independence Measure – B gains. A multiple regression analysis examining age, sex, Mini-Mental State Examination score, Katz score, type of fracture, surgery versus conservative treatment and the pre-fracture Functional Independence Measure score showed that only the pre-fracture Functional Independence Measure – B scores and Katz scores are the independent variables for motor and self-care gains, respectively.

Conclusions: Pre-fracture motor and not cognitive level has been the most important predictive factor for motor gain after hip fracture. Cognitively impaired hip fracture patients can achieve and maintain the same motor functional gain as normal patients, if they were mobile pre-fracture.
Nutritional status of patients with advanced cancer: the value of using the subjective global assessment of nutritional status as a screening tool
Authors: Thoresen Lene , Fjeldstad Irene , Krogstad Knut , Kaasa Stein , Falkmer Ursula G.
Published: July 2002

In patients suffering from advanced neoplastic disease, malnutrition is a common complication affecting both the survival and quality of life. In order to monitor early dietary interventions, an assessment of patients' nutritional status is essential. We assessed the nutritional status of 46 patients using two different methods: 1) an objective method of nutritional assessment and 2) the subjective global assessment (SGA) technique. It was found that 28 patients were characterized as malnourished by means of the objective method and 30 patients according to the SGA. The correlation of the results of the assessments between the two methods was high and a validation test of the SGA gave a sensitivity of 96% and specificity of 83%. The most frequent symptoms affecting food intake were anorexia, early satiety, dry mouth, pain and nausea. The results show that the SGA represents an easy method for assessment of the nutritional status in such cancer patients and that it can therefore be used as a screening tool. The high incidence of malnutrition in this group of patients, and their rare use of nutrient supplements, both indicate the importance of early nutritional assessment, and nutritional intervention when appropriate.
Response of the Porcupine and Old Crow rivers in northern Yukon, Canada, to Holocene climatic change
Authors: Lauriol B. , Duguay C. R. , Riel A.
Published: July 2002

A major aggradation took place from 8000 BP to 4000 BP in the Porcupine and Old Crow rivers, northern Yukon. The aggradation was a consequence of an increase in flow and the result of a perturbation of the permafrost active layer following the early-Holocene climatic warming of northwestern Canada. These findings are useful for improving our understanding of how natural landscapes and river systems evolved in regions that experienced a permafrost history and, more particurlarly, an increase in climatic warming. This article also contributes to an improved understanding of natural landscape evolution along the Porcupine and Old Crow rivers in eastern Beringia, where there has been much interest in questions related to animal and human migration and adaptation.
Holocene glacier fluctuations of Grovabreen and Holocene snow-avalanche activity reconstructed from lake sediments in Grningstlsvatnet, western Norway
Authors: Seierstad Jorun , Nesje Atle , Dahl Svein Olaf , Simonsen Joachim Riis
Published: July 2002

On the southern side of Grovabreen, a plateau glacier in inner Sunnfjord, western Norway, sedimentological analyses of two lake-sediment cores from Groningstolsvatnet have been made in order to reconstruct the Holocene history of Grovabreen and of local snow-avalanche activity. The lake catchment was deglaciated about 9470 cal. BP and glaciers were absent from the catchment between 9470 and 4700 cal. BP, except for a glacier episode, correlated with the 8200 cal. BP Finse event, between 8420 and 7880 cal. BP. The glacier has existed continuously from 4700 cal. BP to the present, reaching its maximum extension around AD 1840 according to lichenometric dates. Single minerogenic particles >1 mm in the sediments retrieved from Groningstolsvatnet are interpreted as dropstones from dirty snow-avalanches eroding the valley sides and deposited on the frozen lake. A local snow-avalanche chronology has been constructed for the last 10000 calendar years, based on the distribution of dropstones in the cores, with pronounced snow-avalanche activity peaking around 10 100 and 8600 cal. BP. This was at a minimum during the period when there were no glaciers in the lake catchment between-7800 and 4700 cal. BP, but increased somewhat around 7100 and 7400 cal. BP. Other marked snow-avalanche episodes occurred around 4000, 3000, 1900 and 1300 cal. BP, and during the recent decades. The snow-avalanche record is largely in accordance with similar records from western Norway and also with a winter-precipitation curve reconstructed from the Jostedalsbreen region.
Late-Holocene sand invasion and North Atlantic storminess along the Aquitaine Coast, southwest France
Authors: Clarke Michele , Rendell Helen , Tastet Jean-Pierre , Clave Berengere , Masse Laurent
Published: July 2002

Holocene forested coastal dunes of different morphology fringe the Atlantic coast of southwest Aquitaine. Infra-red stimulated luminescence (IRSL) dating has been applied to sands from these dunes in the Aquitaine region in order to test the validity of dune-classification theories. The ages obtained from the dunes show three phases of sand invasion and dune development during the late Holocene: 3000-4000 years ago; 900-1300 years ago; 250-550 years ago. The timing of the most recent phase of sand mobilization. as dated by IRSL, is supported by historical maps and records from the fifteenth to the eighteenth centuries AD, showing problems for human settlement in the region and village abandonment due to dune drift. Sand invasion is driven by an increase in frequency of severe storms in the North Atlantic associated with the cooler periods of the ‘Little Ice Age’ and early 'Mediaeval Warm Period'. The dunes emplaced 900-1300 years ago were naturally fixed by a mixed deciduous and maritime pine forest during the latter part of the 'Mediaeval Warm Period'.
Reactive oxygen species in cell responses to toxic agents
Authors: Feinendegen L E
Published: July 2002

This review first summarizes experimental data on biological effects of different concentrations of ROS in mammalian cells and on their potential role in modifying cell responses to toxic agents. It then attempts to link the role of steadily produced metabolic ROS at various concentrations in mammalian cells to that of environmentally derived ROS bursts from exposure to ionizing radiation. The ROS from both sources are known to both cause biological damage and change cellular signaling, depending on their concentration at a given time. At low concentrations signaling effects of ROS appear to protect cellular survival and dominate over damage, and the reverse occurs at high ROS concentrations. Background radiation generates suprabasal ROS bursts along charged particle tracks several times a year in each nanogram of tissue, i.e., average mass of a mammalian cell. For instance, a burst of about 200 ROS occurs within less than a microsecond from low-LET irradiation such as X-rays along the track of a Compton electron (about 6 keV, ranging about 1 μm). One such track per nanogram tissue gives about 1 mGy to this mass. The number of instantaneous ROS per burst along the track of a 4-meV ¬-particle in 1 ng tissue reaches some 70000. The sizes, types and sites of these bursts, and the time intervals between them directly in and around cells appear essential for understanding low-dose and low dose-rate effects on top of effects from endogenous ROS. At background and low-dose radiation exposure, a major role of ROS bursts along particle tracks focuses on ROS-induced apoptosis of damage-carrying cells, and also on prevention and removal of DNA damage from endogenous sources by way of temporarily protective, i.e., adaptive, cellular responses. A conclusion is to consider low-dose radiation exposure as a provider of physiological mechanisms for tissue homoeostasis.