Sites of airway dilatation in asthma following inhaled versus subcutaneous terbutaline. Comparison of physiologic tests with radionuclide lung images.

In 12 asthmatic subjects with mild to severe airways obstruction, we compared the relative magnitude and sites of airway dilatation of a beta-adrenergic stimulant administered by different routes. Specific airway conductance (SGaw), peak expiratory flow, the sum of the absolute volume of isoflow and residual volume as a percentage of total lung capacity (capacity of isoflow) and the ratio of maximal expiratory flow at 50 per cent of vital capacity breathing 80 per cent helium-20 per cent oxygen to that breathing air (ratio Vmax50) were determined before and after the administration of aerosolized terbutaline (0.5 mg), subcutaneous terbutaline (0.5 mg) or placebo. Increases in SGaw and peak expiratory flow of greater than or equal to 25 per cent were considered to indicate significant dilatation of central airways; increases in ratio Vmax50 of greater than or equal to 0.10 and decreases in capacity of isoflow of greater than or equal to 10 per cent were assumed to reflect dilatation of peripheral airways. In addition, radioaerosol and radioxenon lung imaging was performed to determine the relationship between changes in lung imaging patterns and changes in physiologic indices in response to bronchodilator therapy. Placebo caused little change in lung function or lung imaging. After inhaled terbutaline, SGaw and peak expiratory flow increased greater than or equal to 25 per cent in seven subjects, ratio Vmax50 increased greater than or equal to 0.10 in only three subjects, capacity of isoflow decreased greater than or equal to 10 per cent in only one subject, radioaerosol images showed less central deposition in nine subjects and radioxenon images showed improved distribution and/or washout of xenon in five subjects. After the administration of subcutaneous terbutaline, SGaw and peak expiratory flow increased greater than or equal to 25 per cent in 10 subjects, ratio Vmax50 increased greater than or equal to 0.10 in 10 subjects, capacity of isoflow decreased greater than or equal to 10 per cent in 11 subjects, and radioaerosol and xenon images showed improvement in 11 and eight subjects, respectively. These findings are consistent with the action of inhaled terbutaline mainly on large airways and of subcutaneous terbutaline on both large and small airways. Although reduced central radioaerosol deposition correlated well with physiologic evidence of large airway dilatation, improvement in xenon distribution and washout could be attributed to dilatation of either large and/or small airways.

Small airways in progressive systemic sclerosis (PSS).

Obstructive disease involving peripheral airways has been noted in diffuse interstitial pulmonary disease, including sarcoidosis and cryptogenic fibrosing alveolitis. The possibility of obstruction of small airways in progressive systemic sclerosis (PSS) has been suggested by widespread bronchiolectasis and peribronchial fibrosis noted at necropsy. We performed pulmonary function studies in 39 subjects (22 nonsmokers and 17 smokers) with PSS, most of whom had functional evidence of interstitial pulmonary involvement (increased static recoil pressure and reduced diffusing capacity). The 1 second forced expiratory volume to forced vital capacity ratio (FEV1:FVC) was normal in all subjects. Although the severity of the restrictive process was greater in nonsmokers compared with that in smokers, the maximal mid-expiratory flow rate, closing volume, closing capacity, volume of isoflow, change in maximal expiratory flow at 50 per cent of vital capacity during 80 per cent helium--20 per cent oxygen breathing compared with air breathing (delta Vmax50), ratio of dynamic to static lung compliance at different breathing frequencies and upstream airway conductance at static recoil pressures of 5 and 10 cm H2O were nearly always normal in the nonsmokers but were frequently abnormal in the smokers with PSS. These findings suggest that diffuse interstitial pulmonary disease due to PSS generally does not lead to functional evidence of obstruction in peripheral airways and that when the latter is found it can likely be attributed to the effects of concomitant cigarette smoking.

Imaging experimental pulmonary ischemic lesions after inhalation of a diffusible radioaerosol: concise communication.

Regional lung ischemia was imaged with a rapidly diffusible radioaerosol of pertechnetate. The method is compared with similar techniques using 11C and 15O. The principles involved include (A) the rapid alveolar-capillary diffusion of inhaled radioactive gases (11CO, C15O, and C15O2) and the radioaerosol of 99mTcO4-; (B) the patency of the airways to the ischemic regions; and, most importantly; (C) the much slower tracer removal from lung tissue with a stagnant circulation as opposed to the surrounding normal lung. The 11CO and C15O label the hemoglobin in red blood cells, and the C15O2 labels water in the circulation and in the stagnant ischemic region. The TcO4- probably labels the albumin of the plasma in the embolized regions and in the circulating blood. Experiments involving pulmonary embolism in dogs, proved by pre- and post-mortem angiography and gross post-mortem examination, show that positive ischemic lesions (hot spots) are observed, after TcO4- aerosol and C15O2 gas inhalation, in the embolized region on the same day. Clinical trials with aerosol-inhalation method in suspected pulmonary embolism and now under way.

Imaging small pulmonary ischemic lesions after radioactive carbon monoxide inhalation.

A new method is described for imaging small ischemic regions in the lung immediately after a single breath of radioactive carbon monoxide (11CO). A tungsten-collimated scintillation camera is used to visualize the 0.51-MeV annihilation photons due to the 11C. In normal dogs the entire field is cleared of 11CO within 10 sec. However, in dogs with experimentally occluded 2-mm-diam segmental arteries, the ischemic but well-ventilated segment appears as a region of persistent high radioactivity, due most likely to temporary entrapment of 11CO-labeled red blood cells in the ischemic region. This technique also provides a simple noninvasive means for instantly labeling the systemic circulation without left heart catheterization.

Diagnostic value of fiberoptic bronchoscopy in metastatic pulmonary tumors.

The fiberoptic bronchoscopic procedure (with brushings, washings, and biopsies) was performed and specimens of sputum were obtained before the procedure in 37 patients with cancer metastatic to the lung. Of the 37 patients studied, endobronchial lesions were visualized at bronchoscopic examination in 14 (group 1), and no endobronchial lesion was seen in 23 (group 2). The yield of bronchial brushing and washings was not significantly different in group 1 and 2, whereas examination of sputum obtained before the bronchoscopic procedure and bronchial biopsy in group 1 yielded higher results than the same procedures in group 2. The radiographic findings did not influence the yield with any of the bronchoscopic procedures. The overall positive diagnostic yield from fiberoptic bronchoscopic procedures among these patients was 54 percent (20/37), regardless of their bronchoscopic or radiologic findings.

Measurement of mucociliary transport velocity in the intact mucosa.

A new method for measuring the velocity of the tracheal mucous transport rate in anesthetized dogs is described. The length of the trachea is determined with the bronchoscope as the distance between the larynx and the lower end of the trachea at the level of the carina. A small volume (0.04 to 0.1 ml) of albumin microspheres 5 mgm to 7 mum in diameter labeled with radioactive 99m technetium or 113m indium is deposited on the mucosal surface at the lower end of the trachea via a catheter placed in the inner channel of a fiberoptic bronchoscope. The movement of the microspheres towards the larynx is visualized and recorded using a scintallation camera (Picker Dyna Camera) with a large field of view (30 cm in diameter) for 30 to 60 minutes, depending upon the time required for the spheres to reach the top of the trachea. Polaroid pictures are made immediately and every minute thereafter until the activity reaches the larynx. The data are also recorded and stored on magnetic tape for subsequent analyses by computer. The length in millimeters divided by the time in minutes gives the transport velocity rate. The mean velocity was found to be 19.2 +/- 1.6 mm/min (+/- SE).

Early detection of chronic obstructive pulmonary disease using radionuclide lung-imaging procedures.

One hundred subjects answered a respiratory questionnaire and underwent a physical examination, tests of pulmonary function, and three radionuclide lung-imaging procedures. The results of the radionuclide procedures were compared with each other and with pulmonary function tests and other diagnostic findings to determine their relative sensitivity for detecting evidence of early obstructive airway disease. Perfusion lung imaging was less sensitive than most of the other diagnostic tests evaluated. The aerosol and xenon lung-imaging procedures revealed abnormalities with approximately the same frequency as each other, but more often than any one group of pulmonary function tests, including spirometric data, maximal expiratory flow-volume curves, alveolararterial oxygen gradient, or indices derived from single-breath nitrogen washout. We concluded that xenon and aerosol lung-imaging studies are sensitive and useful screening procedures for detecting evidence of early localized obstructive airway disease and for locating regional abnormalities in the airways of patients with respiratory disease.

NMR imaging investigations of drug delivery devices using a flow-through USP dissolution apparatus.

A system for performing NMR imaging experiments on drug delivery devices within a flow-through dissolution apparatus, USP Apparatus 4, has been developed. The system was used to image the physical changes that occur in solid dosage forms during dissolution in the flow-through apparatus. Simultaneous cumulative drug release measurements were also made. The NMR images obtained under these conditions and the drug release data provide a better understanding of the processes involved in the release of drugs from drug delivery systems based on diffusion, dissolution and osmosis mechanisms.

Use of NMR imaging in the optimization of a compression-coated regulated release system.

Nuclear magnetic resonance (NMR) imaging is routinely used to detect the protons of mobile water molecules within samples. In this investigation, this non-destructive, non-invasive technique was used to determine the cause for faster than predicted drug release from a dissolution-based regulated-release tablet. The NMR images of tablets, from two different formulations, taken at various intervals of time while immersed in static USP dissolution medium showed that the tablet with faster than predicted drug release had a porous coating. The porous coat exposed more of the core surface area to the dissolution medium than desired and this caused an increase in the rate of dissolution of the core. The data presented in this paper demonstrate the usefulness of NMR imaging in solid dosage form development.

Ultrasound biomicroscopy in the diagnosis and management of pars planitis caused by caterpillar hairs.

PURPOSE: To report the use of ultrasound biomicroscopy in the detection of caterpillar hairs in the pars plana in a patient with unilateral pars planitis. METHOD: Ultrasound biomicroscopic imaging of the anterior segment of the eye. RESULTS: Ultrasound biomicroscopy located a hair in the posterior chamber at the first visit and five more in the pars plana 1 month later. This finding was confirmed intraoperatively. CONCLUSION: Ultrasound biomicroscopy is useful in the diagnosis and management of unilateral pars planitis of uncertain cause.

Tack behavior of coating solutions I.

The tackiness of various tablet coating solutions was determined using a parallel plate technique with a tensile testing machine in conjunction with an oscilloscope where the separation force was displayed as a function of time. Measurements were made at various rates of separation on liquid films of constant thickness. Results showed that the force required to split a liquid film increases with an increase in rate of separation, and that tackiness increases with an increase in viscosity. The relation between tack and viscosity was not linear, and a modified Stefan equation was proposed.

Tack behavior of coating solutions III.

The effect of finely divided solids on the tackiness of coating solutions was determined using a parallel-plate technique. Results demonstrated that the tackiness of coating solutions containing relatively low concentration of polymers augments with the increase in concentration and diminishes with the increasing particle size of finely divided solids. In contrast, the tackiness of coating solutions containing high concentrations of polymers is suppressed upon increasing the concentration and decreasing the size of finely divided solids.

Tack behavior of coating solutions II.

The tackiness of coating solutions containing high concentrations of polymers was determined using a parallel plate technique. Kinematics of the film-splitting process was also investigated using a high-speed movie camera. The results showed that the impulse required to split a liquid film of highly concentrated polymer solution (semisolid), in contrast to a dilute solution is related not to viscosity, but to the internal structures of the system. Evidence has been found that the materials that are considered to be tacky in practice, display "delayed elastic effects" and require far larger impulses than nontacky materials.

Fiberoptic bronchoscopy in the diagnosis of lung cancer comparison of pre-and post-bronchoscopy sputa, washings, bruchings and biopsies.

Fiberoptic bronchoscopy (brushings, washings and biopsies) was performed and pre- and post-bronchoscopy sputum cytologies obtained on 70 patients with histopathologically proven lung cancer. Bronchoscopy, with its associated procedures performed in 52 patients with primary bronchogenic carcinoma, was diagnostic in 41 (79%). Of all the various methods of obtaining specimens, bronchial brushing and bronchial biopsy gave the highest percentage yield (67%). However, since brush specimens could be obtained from peripheral lesions under fluoroscopic guidance, a greater number of positive specimens were obtained by this procedure (34) than by forceps biopsy (25), making brushing more useful. Pre- and post-bronchoscopy sputa were positive and thus of value in two cases when brushing and biopsy were both negative. Bronchial washing did not add significantly to the yield of positives and could therefore be eliminated as an unnecessary cost-and time-consuming procedure. Fiberoptic bronchoscopy was not helpful in diagnosing mediastinal tumors (5), lung metastases (7) and bronchial adenomas (6).

A review of childhood admission with perforating ocular injuries in a hospital in north-west India.

A retrospective study of perforating ocular injuries in children below the age of fifteen years was conducted. Eighty patients (eighty-nine eyes) were included in this study. Male children were more susceptible to ocular injury as compared to females (p = < 0.01). Children of the school-going age were the most affected (73.8%). Majority of the injuries occurred in the sports field (p = < 0.01). Playing with bow and arrow, and gillidanda* accounted for majority of the sport injuries (47.2%). Sixty-eight percent of the perforated eyes had no light perception at the end of treatment. Health education on the preventive aspects of ocular injuries in schools as well as through mass media should reduce the incidence of visual loss due to ocular injuries.

Association of AFLP and SSR markers with agronomic and fibre quality traits in Gossypium hirsutum L.

Molecular markers linked to QTL contributing to agronomic and fibre quality traits would be useful for cotton improvement. We have attempted to tag yield and fibre quality traits with AFLP and SSR markers using F(2) and F(3) populations of a cross between two Gossypium hirsutum varieties, PS56-4 and RS2013. Out of 50 AFLP primer combinations and 177 SSR primer pairs tested, 32 AFLP and four SSR primers were chosen for genotyping F(2) individuals. Marker-trait associations were studied for eight agronomic and five fibre quality traits through simple and multiple regression analysis (MRA) using a set of 92 AFLP polymorphic loci and four SSR markers. Simple linear regression analysis (SLRA) identified 23 markers for eight different traits whereas multiple regression analysis identified 30 markers for at least one of the 13 traits. SSR marker BNL 3502 was consistently identified to be associated with fibre strength. While all the markers identified in SLRA were also detected in MRA, as many as 16 of the 30 markers were identified to be associated with respective traits in both F2 and F3 generations. The markers explained up to 41 per cent of phenotypic variation for individual traits. A number of markers were found to be associated with multiple traits suggesting clustering of QTLs for fibre quality traits in cotton.