Biomedical subjects

I Ben-Dov

Publications and source records attributed to I Ben-Dov.

At least 19 recordsLinked to original sources

PubMed2002

[Fatal asthma: who, when, why and how to prevent?].

Despite our understanding of the inflammatory nature of asthma, mortality from the disease has been on the rise. Most deaths follow a protracted course, but some occur abruptly. Many of those who die or who have experienced a near fatal episode share common characteristics (giving hope that many deaths are preventable), such as insufficient steroid therapy, reliance on inhaled bronchodilators, marked peak flow fluctuations, psychiatric disorders and attenuated dyspnea in response to stimuli. No genetic marker has been identified for the at-risk group, but the fall in lung function in response to methacholine dose is high and the ventilatory response to hypoxia is blunted. The last 3 characteristics may be causative. The patient at risk needs to be identified and treated with the goal to normalize lung function (as is usually recommended). However, in this group it may be desirable (though not yet proven) to up-titrate therapy further, with the added goal to minimize peak flow fluctuations and bronchial reactivity. Patients (and families) need to be taught to monitor peak flow and as the disease worsens, by clinical and by written peak flow criteria, to increase inhaled steroids, to use oral steroids, to self inject subcutaneous epinephrine or to sick (urgent) medical attention. This mode of therapy depends on tight patient-physician relation, a pattern of behavior that is not easy to achieve with this group.

Asthma↗

PubMed2000

Why is exercise capacity reduced in subjects with pectus excavatum?

BACKGROUND: Exercise capacity is often limited in subjects with pectus excavatum (PE), but the mechanism is unknown. OBJECTIVES: We attempted to quantify exercise capacity and to investigate whether limitation of venous return to the heart contributes to exercise intolerance in PE. METHODS: A total of 13 patients with PE (mean age, 19 +/- 6 years) and 20 control subjects (mean age, 25 +/- 11 years) underwent sitting and supine incremental cycling and exercise Doppler stroke volume (SV) measurements. RESULTS: Supine peak oxygen uptake (V'O(2)max) for the patients (1351 +/- 345 mL/min) and control subjects (1505 +/- 330 mL/min) was not different. In contrast, sitting V'O(2)max was lower in the patients than in the control subjects, 1480 +/- 462 and 1994 +/- 581 mL/min, respectively (P =.02). Supine exercise SV was not different between groups. Moreover, only in the patients with PE was supine exercise SV, 70 +/- 18 mL, higher than sitting exercise SV, 55 +/- 14 mL (P =.015). The corresponding values for the control subjects were 70 +/- 18 mL and 65 +/- 19 mL (P = NS). CONCLUSIONS: Patients with PE exercising in the sitting position have reduced V'O(2)max and SV, whereas during supine exercise they approached the control values. The supine advantage in PE suggests that upright exercise capacity in this disease is affected by reduced filling of the heart in the non-supine position.

Adult↗

PubMed2000

Marked weight reduction lowers resting and exercise blood pressure in morbidly obese subjects.

Obesity and high blood pressure (BP) often coexist. Weight reduction lowers resting BP but its effect on BP during exercise (a predictor of target organ damage) has not been evaluated. Blood pressure was measured at rest and during cycling, before and after weight reduction induced by gastric restriction. Nineteen subjects (4 male), 41 +/-2 (SEM) years of age and body mass index (BMI) of 43 +/- 0.9 kg/m2, were studied. On each occasion BP was measured at rest, at a steady state of 0 and 25 watts, at peak exercise and 1 min into recovery. Body weight was reduced by 28% +/- 6% and BMI decreased from 43.3 +/- 0.9 to 31.5 +/- 0.7 kg/m2 (P < .01). Both BP and heart rate, at rest and at all exercise intensities, were significantly lower after weight reduction. Resting BP decreased from 133 +/-4/87 +/- 3 mm Hg to 115 +/- 4/77 +/- 2 mm Hg (P < .001), and BP at peak exercise decreased from 181 +/- 8/98 +/- 4 to 162 +/- 6/83 +/- 5 mm Hg (P < .001). The change in resting systolic BP did not correlate with the change in body weight or with the change in heart rate, but it correlated with the baseline systolic BP (R = 0.61; P < .005). It is concluded that marked weight reduction reduces BP at rest and at all exercise intensities. Gastroplasty should be considered as an option in morbidly obese hypertensive patients who are not well controlled with conventional treatment, and who fail to lose or to maintain a reduced weight by calorie restriction alone.

Adult↗

PubMed2000

Effect of thoracic sympathectomy on arm and leg exercise capacity and on lung function.

BACKGROUND: Thoracic T(2-4) sympathectomy (TS) relieves palmar hyperhidrosis. These same roots innervate the heart and the lung. Thoracoscopic TS minimizes damage to the chest wall so that the effect of sympathectomy itself on these organs can be studied. We attempted to determine whether attenuated sympathetic output affects arm or leg exercise tolerance and lung function in young adults who underwent this operation. METHODS: Seven subjects, aged 17-30 years, had lung function tests (water spirometer, Godart, Holland), and leg and arm maximal exercise (CPX, MedGraphics, USA), before and 3-6 months after TS. RESULTS: After TS, resting and exercise heart rate and blood pressure were reduced. Baseline leg and arm peak O(2) uptake, 2.08 (0.6) and 1.44 (0.5) liters/min, respectively, were not different from the post-TS values, 2.06 (0.7) and 1.54 (0.5) liters/min (nonsignificant). Post-TS lung functions were not significantly reduced. CONCLUSION: Thoracoscopic T(2-4) sympathectomy does not lead to a clinically important fall in lung function and does not compromise arm or leg exercise capacity. Therefore, TS can be done safely in young subjects with palmar hyperhidrosis.

Adolescent↗

PubMed1999

Drug-resistant pulmonary tuberculosis in Israel, a society of immigrants: 1985-1994.

SETTING AND OBJECTIVES: Drug-resistant tuberculosis was uncommon in Israel until 1985, when the waves of immigration began. We studied the incidence and clinical course of resistant pulmonary tuberculosis nationwide. DESIGN: Isolates of Mycobacterium tuberculosis between 1985 and 1994 were surveyed. Data on 150 patients with resistance and 110 patients with drug-sensitive disease were reviewed. Ethnic origin, type of resistance, radiological findings and outcome were analysed. RESULTS: In total, 16.7% of the isolates showed resistance to at least one drug; 58% had resistance to multiple drugs. In 67% of the patients the resistance was primary. Most patients were immigrants from the former USSR and from Ethiopia; none were Israeli-born Jews. Mortality with resistance was 10%, and was highest (14%) with multiple drug resistance. Mortality among drug-resistant cases was lowest (3%) among Ethiopian Jews. Cavities and extensive disease were more common with drug resistance. CONCLUSION: Drug resistance has become relatively common in Israel due to immigration from the former USSR and Ethiopia. It is more extensive radiologically and carries a poorer outcome.

Drug Resistance, Microbial↗

PubMed1999

Pulmonary alveolar proteinosis in Israel: ethnic clustering.

BACKGROUND: Pulmonary alveolar proteinosis is a rare disease in which a surfactant-like phospholipid-rich protein accumulates in the lungs. The disease is amenable to effective therapy by total lung lavage. OBJECTIVES: To investigate the prevalence, ethnic distribution and course of PAP in Israel. METHODS: A countrywide survey was conducted during which pulmonologists were questioned about patients with PAP. The patients were examined and their charts, radiological images, pathological slides and physiological data were reviewed. RESULTS: The survey yielded 15 patients (8 females) during the period 1976-98 (14 in the last decade), giving a prevalence of 3.7 x 10(6) and an incidence of 0.36 x 10(6)/year. Mean age of the patients was 33 +/- 13 years (range 0.5-46 years). Seven patients were North African (two were siblings), four were from Iraq and two were Arabs; there was only one Ashkenazi Jew (a child). Symptoms at the onset were dyspnea and chest pain. Spontaneous remission occurred in at least 3 patients, and 10 patients required 1-4 bronchoalveolar lavage treatments. The subjective and physiological response was favorable, but there was less consistent radiological improvement. CONCLUSION: The prevalence of PAP in Israel is approximately 3.7 x 10(6). Most cases occurred in Jews who had immigrated from North Africa or Iraq, and two were siblings. The prevalence among the Arab population appears to be similar. This clustering suggests the existence of a genetic predisposition. The course of the disease appears to be similar to that reported elsewhere.

Adolescent↗

PubMed1998

[Recurrent tuberculosis in a psychiatric hospital, recurrent outbreaks during 1987-1996].

During 1987-1996, 39 of 720 patients hospitalized (most for severe schizophrenia) were diagnosed as having active pulmonary tuberculosis (5.4%, 975 per 105 per year). In 1992-1993, after a cluster of 5 cases was found, all patients were screened by PPD skin test and chest X-ray and 16 more cases were identified. Diagnosis was confirmed bacteriologically in only 10 of them but there were typical radiological findings in the others. 39 were treated with a multi-drug regimen. In addition, 333 exposed patients and 21% who had converted their skin tests were given isoniazid preventive therapy. A small increase in levels of liver enzymes was common, but significant abnormality (over 4 times the upper limit of normal) was found in only 7 patients, in whom therapy was therefore stopped or changed. During a follow-up period of 4 years, 2 more developed tuberculosis and 33 converted their PPD reactivity status. We conclude that an outbreak of tuberculosis in a psychiatric hospital can be controlled with a relatively low rate of side-effects by using systematic diagnostic and therapeutic measures. However, single step screening is not sufficient. Routine screening of all new patients, a high index of suspicion and contact investigation are needed.

Antitubercular Agents↗

PubMed1998

Improved breathing capacity during exercise in severe obstructive airway disease.

In severe COPD, ventilation at peak exercise may exceed the resting maximal voluntary ventilation (MVV). We investigated the mechanisms by which the breathing capacity can improve during exercise in COPD. A total of 13 patients with an FEV1 of 32+/-12% (SD) predicted, performed an incremental maximal exercise test and FVC and MVV maneuvers at rest and during constant work rate exercise. Maximal exercise ventilation was 3+/-2 L/min higher than resting MVV. Breathing capacity improved during exercise; resting MVV was 30+/-3 (SE) L/min, while it reached 38+/-3 L/min during exercise (P < 0.002). FEV1 improved from 0.86+/-0.1 L at rest to 1.01+/-0.1 L during exercise (P < 0.004), which is consistent with exercise-induced bronchodilatation. It is concluded that in severe COPD, breathing capacity improves during exercise. Assuming that the change in FEV1 reflects improved airway function, these data suggest that exercise-induced bronchodilatation contributed to that improvement.

Adult↗

PubMed1997

Piezoelectric immunosensors for urine specimens of Chlamydia trachomatis employing quartz crystal microbalance microgravimetric analyses.

The assembly of a biosensor for Chlamydia trachomatis based on the microgravimetric quartz crystal microbalance (QCM) analysis of the bacteria association to an antibody-functionalized electrode is described. The sensing interfaces consist of a primary cystamine monolayer assembled onto Au electrodes associated with the quartz crystal. The monolayer is further modified with sulfosuccinylimidyl 4-(p-maleimidophenyl)butyrate (sulfo-SMPB) and the goat IgG-anti-mouse IgG Fc-specific Ab or the fragmented F(ab')2 anti-mouse IgG Ab that act as sublayers for the association of the sensor-active anti-C. trachomatis LPS-Ab. Bacteria in the concentration range from 260 ng.mL-1 to 7.8 micrograms.mL-1 are sensed by the functionalized crystals. The association of C. trachomatis to the sensing interface can be confirmed and amplified via interaction of the crystal with various anti-C. trachomatis antibodies. Urine-pretreated functionalized quartz crystals are applied in the analysis of C. trachomatis in urine samples. The sensitivity limits of the electrodes for sensing the bacteria in urine samples corresponds to approximately 260 ng.mL-1. The functionalized crystals assembled via association of anti-C. trachomatis LPS-Ab to the fragmented F(ab')2 anti-mouse IgG Ab reveal long-term stability upon storage at 4 degrees C.

Antibodies, Bacterial↗

PubMed1997

Photochemically-activated electrodes: application in design of reversible immunosensors and antibody patterned interfaces.

Antigen monolayers assembled onto Au electrodes associated with a quartz crystal act as electrochemical or microgravimetric quartz-crystal-microbalance (QCM) sensing interfaces for the complementary antibody. Electrochemical analysis of the antibody (Ab) is based on the insulation of the antigen monolayer electrode by the associated Ab towards a redox probe in the electrolyte solution. Ferrocene-modified glucose oxidase (Fc-GOx) and glucose are employed as redox probes for the amperometric transduction of the Ab association to the electrode. Bioelectrocatalyzed oxidation of glucose provides an electrochemical route to amplify the antigen-Ab complex formation. Electrochemical analysis of the dinitrophenyl antibody, DNP-Ab, by a dinitrophenyl-lysine monolayer electrode is presented. QCM analysis of the Ab is based on the frequency changes of the quartz crystal resulting from the association of the Ab to the crystal assembly. This method is discussed with the analysis of the fluorescein antibody, Flc-Ab, using a fluorescein monolayer-modified quartz crystal. A novel method to tailor reversible immunosensor devices by the application of photoisomerizable antigen monolayers on electrodes is presented. The antigen is modified by photoactive units exhibiting reversible photoisomerizable properties. In one photoisomer state, the antigen exhibits affinity for the Ab and enables its electrochemical or QCM analysis. Photoisomerization to the complementary state perturbs the antigen structure and the monolayer lacks affinity for the Ab. This enables the washing-off of the Ab and the regeneration of the actively sensing interface by a second illumination process that restores the antigen monolayer-modified surface. This method is exemplified by the development of a reversible DNP-Ab sensing electrode. N-Mercaptobutyl dinitrospiropyran was assembled as a photoisomerizable monolayer on a Au electrode. The dinitrospiropyran monolayer, SP-state, exhibits affinity for the DNP-Ab and enables the amperometric detection of the Ab using Fc-GOx and glucose as redox probe. The complementary photoisomerized protonated dinitromerocyanine monolayer, MRH(+)-state, lacks affinity for the DNP-Ab. By photoisomerization of the DNP-Ab associated with the SP-monolayer electrode to the MRH(+)-monolayer state, the DNP-Ab is washed-off, and by a second illumination process, the MRH(+)-monolayer is re-isomerized to the SP-monolayer assembly, which is the active interface for further analysis of the DNP-Ab. Cyclic amperometric detection of the DNP-Ab by the photoisomerizable dinitrospiropyran monolayer is demonstrated. The association of the DNP-Ab to the SP-monolayer electrode and the dissociation of the Ab from the MRH(+)-monolayer electrode are confirmed by QCM experiments using a dinitrospiropyran monolayer-modified quartz crystal. The insulating features of an antigen-Ab complex on a conductive surface and the photochemically controlled association of an antibody to a photoisomerizable monolayer assembled onto the surface were used to develop means for micropatterning of surfaces by the antibody. A dinitrospiropyran antigen monolayer was assembled onto conductive ITO glass. A DNP-Ab solution was used as 'ink solution' to pattern the surface. The Ab-pattern was imaged by electrochemical copper deposition onto the Ab-lacking surface domains. The dinitrospiropyran monolayer assembled onto ITO or Pyrex glass surfaces was employed as an active interface for the photolithographic patterning of the surface with the DNP-Ab. (ABSTRACT TRUNCATED)

Antigen-Antibody Reactions↗

PubMed1997

Effect of venous obstruction of lower extremities on exercise tolerance.

The effect of venous obstruction on effort tolerance is not well appreciated. We studied a patient with severe lower body venous obstruction (with near normal heart and lung function) who had marked exercise intolerance. Peak O2 uptake for leg exercise was reduced, but peak O2 uptake for upper extremities was normal. This difference indicates that severe venous obstruction can lead to exercise limitation.

Arm↗

PubMed1994

Dynamics of oxygen uptake for submaximal exercise and recovery in patients with chronic heart failure.

STUDY DESIGN AND OBJECTIVES: Attainment of a steady state for oxygen uptake (VO2) during constant work rate exercise has been reported to take longer for patients with chronic heart failure (CHF) compared with normal. The steady state is also delayed in normal subjects during high-intensity exercise compared with moderate exercise, however, and the delay correlates with the degree of associated lactic acidosis. To determine whether prolonged kinetics of VO2 are attributable solely to the reduction of exercise capacity in CHF, VO2 kinetics were compared for patients with CHF and normal subjects, both for exercise of matched absolute work rate and for matched relative work intensity. SUBJECTS: Eighteen men with CHF and 10 normal men. METHODS AND RESULTS: Subjects performed 6 min of constant work rate cycle ergometry with breath-by-breath measurement of VO2. Patients were studied using 25 W, and a work rate midway between the lactic acidosis threshold and maximal capacity (50 percent delta). Normal subjects were tested similarly, and also at a work rate matched to the patients' average 50 percent delta work rate. The VO2 kinetics were characterized by the mean response time (MRT) to attain the 6 min VO2 value. Rates of recovery of VO2 were analyzed for 2 min following exercise. For the same absolute work rate, VO2 MRTs were significantly longer for patients than controls (25 W, 67 +/- 26 vs 37 +/- 25 s; approximately 60 W, 87 +/- 20 vs 54 +/- 27 s), but there was no significant difference in VO2 MRT between the two groups at a matched intensity of 50 percent delta (87 +/- 20 vs 81 +/- 18 s). However, the decrease in VO2 during 2 min of recovery was slower for the patients on all comparisons, even for matched exercise intensity. CONCLUSION: The VO2 dynamics for submaximal exercise are slowed in CHF. The slower dynamics are not entirely accounted for by the relatively higher intensity of a given work rate, since delayed recovery is evident even at a matched relative work intensity. Exercise intolerance in CHF is characterized not only by decreased maximal exercise capacity, but also by slower adaptations to and from submaximal levels of exercise.

Anaerobic Threshold↗

PubMed1994

Physiological and neuropsychological effects of theophylline in chronic obstructive pulmonary disease.

The effect of oral theophylline on clinical course, exercise, neuropsychological performance and bronchial reactivity was studied in chronic airflow obstruction. Twelve patients with chronic obstructive pulmonary disease (COPD) [mean age 62.4 +/- 1.6 years (SE), and forced expiratory volume in 1 sec of 1.15 +/- 0.1 l] were randomized to 4 weeks treatment with oral theophylline followed by 4 weeks of placebo, in a double-blind fashion. During each period, patients underwent clinical evaluation, incremental exercise, a battery of neuropsychological tests measuring a wide range of cognitive functions, and an inhaled methacholine provocation. On the active drug (levels 9.5 +/- 1 mg/l), vital capacity and maximal breathing capacity were 16 +/- 7% and 20 +/- 7% respectively, higher relative to placebo (P < 0.04). Exercise capacity, as reflected by peak O2 uptake and the anaerobic threshold, improved 14 +/- 5% and 18 +/- 5% (P < 0.04). In contrast, bronchial responsiveness to inhaled methacholine and the mean scores on the neuropsychological tests were not significantly altered by the drug. Clinical symptoms were unaltered, but mild side effects were more common on theophylline. We concluded that in moderate to severe COPD, theophylline treatment, at the low range of the therapeutic dose, improves lung function and exercise capacity. This improvement is achieved with no detectable alteration of bronchial reactivity to methacholine and with no deleterious effect on cognitive functions.

Aged↗

PubMed1993

O2 uptake kinetics in response to exercise. A measure of tissue anaerobiosis in heart failure.

Oxygen uptake (VO2) reflects the rate of aerobic regeneration of high-energy phosphate compounds (primarily adenosine triphosphate [ATP]). Since lactate increase is thought to result from an inadequate rate of aerobic ATP regeneration, it might be expected that lactate increase would be associated with a delayed attainment of steady state for VO2 in response to constant load exercise. Similarly if mitochondrial ATP regeneration during exercise is inadequately supported by O2 transport mechanisms, adenosine diphosphate (ADP) and purine nucleotide by-products, such as hypoxanthine, should increase. This study investigated the relationship between VO2 kinetics during exercise and accompanying changes in blood lactate and hypoxanthine values in heart failure patients, as a model of compromised O2 transport. Twenty-five patients with chronic heart failure performed cycle ergometry for 6 min at 25 W and at a work rate midway (50 percent delta) between their lactic acidosis threshold (LAT) and peak VO2. Ventilation and gas exchange were measured breath by breath, and venous lactate, hypoxanthine, norepinephrine, and epinephrine were determined at rest and 2 min after each test. The slow component of VO2 kinetics was quantified as the rise in VO2 from the third to the sixth minute of exercise (delta VO2 [6-3]). Ten age- and size-matched normal subjects served as control subjects. delta VO2 (6-3) was correlated with the increase in lactate (r = 0.71, p < 0.001), hypoxanthine (r = 0.61, p < 0.001), and norepinephrine (r = 0.41, p < 0.01) but not epinephrine in response to exercise in the heart failure patients. The delta VO2 (6-3) and delta lactate were both greater in the patients than in the control subjects at similar absolute work rates (54 +/- 20 and 60 W, respectively). However, the slope of the relationship between delta La and delta VO2 (6-3) for the patient and normal groups was indistinguishable. The lactate increase was correlated with hypoxanthine increase (r = 0.66, p < 0.001), but not norepinephrine or epinephrine. In summary, VO2 kinetics in response to exercise reflects delayed attainment of the steady state in heart failure patients, which is correlated with increases in lactate and hypoxanthine, markers of increased anaerobic metabolism.

Acidosis, Lactic↗

PubMed1992

Evidence that circulatory oscillations accompany ventilatory oscillations during exercise in patients with heart failure.

Periodic breathing (PB) during exercise in patients with congestive heart failure (CHF) is associated with prominent oscillations (OSC) of O2 uptake (VO2). We hypothesized that the VO2 OSC represent OSC in true O2 exchange, resulting from concomitant cardiac output fluctuations and are not merely due to OSC of lung O2 stores. We compared the amplitude of the OSC of VO2, ventilation (VE), and end-expiratory lung volume (EELV) in 17 patients with CHF and PB and in seven healthy control subjects who volitionally simulated PB. Subjects underwent an incremental and/or a constant work-rate exercise test. VE and VO2 were measured breath by breath. EELV change was estimated by summing the difference between inspiratory and expiratory tidal volumes for each breath. The amplitude of the OSC, delta, is expressed as the ratio of the difference between the peak and nadir of the oscillating variable divided by its mean [delta = (peak - nadir)/mean]. In CHF, during incremental testing, the amplitude of the VE OSC was smaller than that of the VO2 OSC (delta VE = 49 +/- 15% [SD], delta VO2 = 63 +/- 25%, p less than 0.01). In contrast, during volitional PB in the control subjects, VE OSC were larger than VO2 OSC (delta VE = 48 +/- 12%, delta VO2 = 25 +/- 11%, p less than 0.01). This suggests that changing VE itself cannot account for the marked VO2 OSC seen in CHF. In the patients, EELV showed no systematic OSC, did not correlate with delta VO2, and was not significantly different from zero.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1991

O2 uptake in hyperthyroidism during constant work rate and incremental exercise.

To investigate the effect of hyperthyroidism on the pattern and time course of O2 uptake (VO2) following the transition from rest to exercise, six patients and six healthy subjects performed cycle exercise at an average work rate (WR) of 18 and 20 W respectively. Cardiorespiratory variables were measured breath-by-breath. The patients also performed a progressively increasing WR test (1-min increments) to the limit of tolerance. Two patients repeated the studies when euthyroid. Resting and exercise steady-state (SS) VO2 (ml.kg-1.min-1) were higher in the patients than control (5.8, SD 0.9 vs 4.0, SD 0.3 and 12.1, SD 1.5 vs 10.2, SD 1.0 respectively). The increase in VO2 during the first 20 s exercise (phase I) was lower in the patients (mean 89 ml.min-1, SD 30) compared to the control (265 ml.min-1, SD 90), while the difference in half time of the subsequent (phase II) increase to the SS VO2 (patient 26 s, SD 8; controls 17 s, SD 8) were not significant (P = 0.06). The O2 cost per WR increment (delta VO2/delta WR) in ml.min-1.w-1, measured during the incremental period (mean 10.9; range 8.3-12.2), was always within two standard deviations of the normal value (10.3, SD 1). In the two patients who repeated the tests, both the increment of VO2 from rest to SS during constant WR exercise and the delta VO2/delta WRs during the progressive exercise were higher in the hyperthyroid state than during the euthyroid state.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

Effect of hyperoxia on bronchial response to inhaled methacholine.

Bronchial reactivity to methacholine (MCH) under normoxic and hyperoxic conditions was studied in a double-blind controlled study in 10 normal subjects and nine asthmatic patients. The normal volunteers were challenged while breathing dry, 21% and 100% O2, and the maximal percent falls in forced expired volume in is (FEV1) following inhalation of the highest concentration of MCH (64 mg/ml) were 8 +/- 5% and 9 +/- 8%, respectively; P = NS. The asthmatic patients had their MCH challenge breathing the same gas composition and the provocative concentrations that caused a 20% fall in FEV1 (PC20) were 0.18 mg/ml (range 0.06-5.73) and 0.25 mg/ml (range 0.07-8.49), respectively, which were statistically not significantly different. We conclude that in humans, 100% O2 does not affect bronchial reactivity to MCH.

Administration, Inhalation↗

PubMed1991

Endobronchial actinomycosis simulating bronchogenic carcinoma. Diagnosis by bronchial biopsy.

Five cases of actinomycosis of the main bronchi or trachea which were suggestive clinically of bronchogenic carcinoma are described. In four patients the correct diagnosis was made by a bronchial biopsy or wash, or both. Three of them recovered following antibiotic treatment, and one died a few days after bronchoscopy. In one case the Actinomyces were found in the bronchial wash retrospectively following diagnosis of pulmonary actinomycosis in the lobectomy specimen. A concomitant endobronchial lipoma was found in one of the patients. The diagnosis of pulmonary actinomycosis by bronchial biopsy may save the patient major surgical intervention.

Actinomycosis↗