[Primary lung cancer in Taiwan].
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Female↗
Biomedical subjects
D B Chang
Publications and source records attributed to D B Chang.
Lobar bronchioloalveolar carcinoma: an ultrasound study.
To assess whether chest ultrasound (US) can be useful in the diagnosis of lobar bronchioloalveolar carcinoma, we retrospectively analyzed the US patterns of eight patients with bronchioloalveolar carcinoma presenting with lobar consolidation. For comparison, 15 patients with lobar consolidation of a benign etiology were also analyzed. We found that the US patterns of lobar bronchioloalveolar carcinoma had a characteristic homogeneous, echogenic pattern. The air-bronchograms and air-alveolograms were scarce when compared to benign consolidation. The sensitivity of using these US criteria in discriminating lobar bronchioloalveolar carcinoma was 75%, and the specificity was 93%. We also assessed the yield of US-guided transthoracic cutting biopsies in the diagnosis of lobar bronchioloalveolar carcinoma. The diagnostic rate of the US-guided cutting biopsy was 100%, which was superior to other diagnostic procedures, such as sputum cytology (37%), fiberoptic bronchoscopy with brushing or biopsy (32%) and trans-thoracic needle aspiration cytology (50%). None of the patients developed complications. We conclude that the distinct US pattern for lobar bronchioloalveolar carcinoma is a helpful diagnostic sign, and the US-guided biopsy is a useful approach in the diagnosis of lobar bronchioloalveolar carcinoma.
Adenocarcinoma, Bronchiolo-Alveolar↗
Age trends in lung cancer.
To investigate the relationship between the stages of cancer development and the age trends in histologic type found at the time of disease diagnosis, we studied 1,669 patients with histologically proven lung cancer. These patients were examined at the National Taiwan University Hospital using Mantel-Haenszel Chi-square testing to determine a linear trend. These patients were divided into three age groups: group 1 (< 45 years), 141 patients (8%); group 2 (45-64 years), 946 patients (57%); group 3 (65 years or more), 582 patients (35%). The ratio of men to women was 1.4 in group 1, 2.5 in group 2 and 2.3 in group 3. In men, there was a significant trend for the proportion of squamous cell carcinoma to increase from 26% to 42% and that of adenocarcinoma to decrease from 52% to 34% as age increased. In women, an age trend for histologic type was not observed. There was also a significant trend for local-stage squamous cell carcinoma in men to increase from 18% in group 1 to 35% in group 2 and to 42% in group 3. In men, but not in women, local-stage large cell carcinoma increased from 20% in group 1 to 31% in group 2 and to 64% in group 3. However, the age-stage trend for other cell types was not significant in men.(ABSTRACT TRUNCATED AT 250 WORDS)
Adenocarcinoma↗
Painful tonic spasms: an interesting phenomenon in cerebral ischemia.
We report a case of bilateral cerebral ischemia with frequent painful tonic spasms involving face, both upper and sometimes both lower extremities. The spasms subsided after treatment with diazepam.
Arm↗
Lung abscesses: US examination and US-guided transthoracic aspiration.
Examinations with ultrasound (US) and US-guided transthoracic aspiration were conducted in 35 patients to enable diagnosis of lung abscesses. Thirty-three of the abscesses (94%) were demonstrated at US, while two lesions were not depicted. At US, lung abscesses were depicted as hypoechoic lesions with irregular outer margins and an abscess cavity that was manifested as a hyperechoic ring. Twenty-five abscesses (71%) had local adhesion to parietal pleura (lesion-pleura symphysis). US-guided transthoracic needle aspiration of fluid from the abscess cavity was performed successfully in 31 of 33 patients (94%). A total of 65 pathogens were isolated from 31 aspirates (41 anaerobes and 24 aerobes), not-withstanding the fact that 23 of the patients had been previously treated with antibiotics. Only two of 65 pathogens (3%) could be recovered from blood culture, seven (11%) from sputum culture, and two from bronchoalveolar lavage (3%). Two patients developed minimal pneumothorax. The authors conclude that US examination and US-guided transthoracic aspiration are useful and safe diagnostic methods of collecting specimens to enable accurate diagnosis of lung abscesses.
Adolescent↗
Evaluation of ultrasonically guided biopsies of mediastinal masses.
Eighty patients with roentgenographic evidence of mediastinal abnormalities were examined with ultrasonography. Fifty-four lesions were malignant, and 26 lesions were benign. The histologic diagnoses were confirmed by ultrasonically guided fine needle aspiration/cutting needle (Tru-Cut) biopsy, surgical specimens, or transbronchial biopsy. There were no unique ultrasonographic features for diagnosis of specific tumors. Ultrasonically guided aspiration biopsies (UGAB) were performed in 44 of the malignant lesions and in 14 of the benign lesions (nine of the noncystic lesions and five of the cystic lesions). Cytologic diagnosis of malignancies was obtained in 34 (77 percent) of these 44 malignancies; however, accurate histologic classifications of malignancies were achieved in only 24 (55 percent). Accurate diagnoses were achieved in only three (33 percent) of the nine noncystic benign lesions. Ultrasonically guided cutting biopsies (UGCB) were performed in 24 malignant and five benign lesions. All attempts yielded satisfactory specimens for histologic diagnosis. Using UGAB and UGCB together, a positive diagnosis was achieved in 89 percent (39/44) of the malignancies, and accurate histologic diagnosis was achieved in 89 percent and 78 percent (7/9) in malignant and benign noncystic lesions, respectively. Correct histologic diagnosis with UGAB alone is lower in thymoma (55 percent [6/11]) and lymphoma (30 percent [3/10]) but higher in lung cancer (67 percent [8/12]) and metastatic cancer (78 percent [7/9]). There were no complications in this series. We conclude that ultrasonography with UGAB has a high diagnostic yield in diagnosing mediastinal tumors, and UGCB is necessary for thymic tumors, lymphoma, and benign lesions.
Adolescent↗
Ultrasound-guided pleural biopsy with Tru-Cut needle.
We conducted a study of ultrasound (US)-guided pleural biopsy with a Tru-Cut needle and made a comparison with the results of a traditional pleural biopsy with an Abrams needle. A total of 49 patients with unilateral pleural effusion were included in this study. Twenty-four patients underwent a traditional pleural biopsy with an Abrams needle, and 25 patients underwent a US-guided pleural biopsy with a Tru-Cut needle. The age, sex, and underlying diseases in both groups were compatible. The amount of effusion was much less in the Tru-Cut group. In the patients who underwent the US-guided pleural biopsy with a Tru-Cut needle, the diagnostic sensitivity in pleural tuberculosis was 86 percent (6/7) and in pleural neoplasia it was 70 percent (7/10). In the patients who underwent traditional pleural biopsy with an Abrams needle, the diagnostic sensitivity in pleural tuberculosis was 20 percent (2/10) and in pleural neoplasia it was 44 percent (4/9). The result of US-guided pleural biopsy with a Tru-Cut needle was better than that of pleural biopsy with an Abrams needle, especially in pleural tuberculosis. No complication was found in the Tru-Cut group, but breakage and dislodgment of the tip of an Abrams needle occurred in one patient. The higher diagnostic yield in the Tru-Cut group may be attributed to the US guidance that can delineate the focal pleural abnormalities for biopsy. In conclusion, US-guided pleural biopsy by using a Tru-Cut needle was simple, safe, and well tolerated. It was particularly useful for patients with pleural tumor, thickened pleura, small amounts of pleural effusion, or loculated pleural effusion.
Adult↗
Metallic weakness and breakage of Abrams pleural biopsy needle.
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Biopsy, Needle↗
Lung tumors associated with obstructive pneumonitis: US studies.
Eleven patients who had lung tumors associated with obstructive pneumonitis and who failed to yield diagnostic material at conventional bronchoscopic biopsy underwent real-time ultrasonographic (US) studies and US-guided aspiration biopsy. Sonography of the consolidated lung showed a wedge-shaped hypoechoic lesion containing a fluid bronchogram. The presumed obstructing tumor was seen as a hypoechoic nodule near the hilum or as a well-defined hyperechoic mass inside the partially consolidated lung. Computed tomography (CT) was superior to US in demonstrating the bronchial obstruction (P less than .05). However, there were no significant differences between CT and US in demonstrating the obstructing tumor (P greater than .10). In all 11 patients the diagnosis was made by means of US-guided transthoracic aspiration biopsy and in eight patients also by means of Trucut biopsy. No complications were observed in the studies. It is concluded that US and US-guided aspiration biopsy are useful adjunct diagnostic techniques for lung tumor patients with obstructive pneumonitis.
Aged↗
Ultrasonic evaluation of cervical lymphadenopathy.
Seventy-seven patients with various underlying diseases underwent real-time ultrasonographic study of the neck. The sonography of lymph nodes can be round or ovoid shaped, discrete hypoechoic nodules, or multiple confluent lobulated heterogeneous or homogeneous hypoechoic masses. Venous invasion by a malignant lymph node can also be demonstrated by ultrasonography as a loss of echogenicity in the vessel wall. Twenty-five patients with malignant cervical lymph nodes showed homogeneous discrete hypoechoic nodules. Eleven patients with malignant lymph nodes showed a multiple confluent lobulated hypoechoic picture, among them, 2 patients also had discrete hypoechoic nodules. Eight patients with multiple confluent lymph nodes showed evidence of venous invasion. Among 42 patients with a clinically palpable neck mass, 1 showed venous thrombosis in the internal jugular vein, 2 had abscesses, and 3 had normal musculo-skeletal tissues. Among 35 patients with clinically impalpable cervical lymph nodes, 5 patients had cervical lymphadenopathy. All 41 patients with sonographically detectable lymph nodes underwent aspiration cytology or biopsy, and 36 of these showed malignancy, 4 TB lymphadenitis and 1 nonspecific inflammation. No complication was observed in this series. We conclude that ultrasonography is a valuable tool to evaluate cervical lymphadenopathy and to clarify the histopathological features of the affected lymph nodes with the aid of aspiration cytology.
Adolescent↗
The nature of phonons and solitary waves in alpha-helical proteins.
A parametric study of the Davydov model of energy transduction in alpha-helical proteins is described. Previous investigations have shown that the Davydov model predicts that nonlinear interactions between phonons and amide-I excitations can stabilize the latter and produce a long-lived combined excitation (the so-called Davydov soliton), which propagates along the helix. The dynamics of this solitary wave are approximately those of solitons described using the nonlinear Schrödinger equation. The present study extends these previous investigations by analyzing the effect of helix length and nonlinear coupling efficiency on the phonon spectrum in short and medium length alpha-helical segments. The phonon energy accompanying amide-I excitation shows periodic variation in time with fluctuations that follow three different time scales. The phonon spectrum is highly dependent upon chain length but a majority of the energy remains localized in normal mode vibrations even in the long chain alpha-helices. Variation of the phonon-exciton coupling coefficient changes the amplitudes but not the frequencies of the phonon spectrum. The computed spectra contain frequencies ranging from 200 GHz to 6 THz, and as the chain length is increased, the long period oscillations increase in amplitude. The most important prediction of this study, however, is that the dynamics predicted by the numerical calculations have more in common with dynamics described by using the Frohlich polaron model than by using the Davydov soliton. Accordingly, the relevance of the Davydov soliton model was applied to energy transduction in alpha-helical proteins is questionable. We conclude that the Raman lines that have been assigned to solitons in E. coli are either associated with low frequency normal modes or are instrumental- or fluorescence-induced artifacts.
Mathematics↗
Temperature-sensitive aspects of evoked and spontaneous transmitter release at the frog neuromuscular junction.
1. The temperature dependence of presynaptic processes involved in neuromuscular transmission was studied by rapidly increasing the temperature of cooled frog neuromuscular junctions by 4--10 degrees C using pulses from a neodymium laser. The temperature elevation was complete within 0.5 msec, and decayed back to control levels with a time constant of about 7--8 sec. 2. Temperature jumps completed before nerve stimulation increased the quantal content and decreased the latency of the end-plate potential (e.p.p.). The Q10 for e.p.p. quantal content in low [Ca2+] Ringer averaged about 3.9 over the range 1--18 degrees C. 3. Temperature jumps occurring during the synaptic delay (the interval between the presynaptic action potential and the onset of the e.p.p.) also increased the quantal content and decreased the latency of the e.p.p. These effects diminished as the onset of the temperature jump was moved closer to the expected onset of the e.p.p. Temperature jumps applied after the onset of the e.p.p. immediately accelerated the time course of the e.p.p. but did not significantly alter quantal content. These results demonstrate that the magnitude and timing of evoked release are influenced by temperature-sensitive processes that operate both during and shortly after the presynaptic nerve action potential, but are largely complete before the onset of release. 4. Temperature jumps were applied at various times during the interval between two nerve stimuli. The amplitude of the second e.p.p. decreased as the temperature jump was moved earlier in the interstimulus interval, suggesting that the rise in temperature following the first nerve stimulus accelerates the decay of facilitation. When the temperature jump was moved from 10 msec after to 10 msec before the onset of the first e.p.p., the amplitude of the second e.p.p. either decreased or showed no change. The fact that the second e.p.p. did not increase suggests that the temperature-sensitive processes that increase the quantal content of the conditioning e.p.p. do not greatly increase the facilitation following that e.p.p. 5. Temperature jumps immediately accelerated the time course of spontaneous miniature end-plate potentials (m.e.p.p.s) and increased their frequency. Experiments using slow temperature changes revealed that the Q10 for m.e.p.p. frequency in normal Ringer is about 10 over the range 10--20 degrees C. M.e.p.p. frequency was much less sensitive to temperature changes below about 10 degrees C. When the nerve terminal was depolarized by 20 mM-K+ in the presence of Ca2+, the Q10 for the rate of spontaneous release over the range 10--20 degrees C decreased to about 4, similar to the Q10 for e.p.p. quantal content. In the absence of extracellular Ca2+ the Q10 for m.e.p.p. frequency in 20 mM-K+ remained near 10. 6. The marked difference in Q10S for spontaneous transmitter release under different experimental conditions suggests that not all transmitter release uses identical mechanisms...
Action Potentials↗
A comparative study of the mechanical properties in aging alveolar wall.
Alveolar wall from the lung of aging humans shows a progressive decrease in maximal extensibility, which should follow an increase in resting tissue length rather than a reduction in maximal length. An increase in resting tissue length is compatible with the change in lung volumes and reduction in elastic recoil that occurs with time. A model of the lung was used to compare the effects of a change in resting tissue length in diminishing elastic recoil with that of a reduction in the volume density of the elastic elements (emphysema). Such differentiation is important in selecting an animal that may model the aging or emphysematous lung. In the rat, rabbit, and horse, alveolar walls show no decrease in maximal extensibility with age. In the male monkey (M. nemestrina and M. mulatta) between birth and 2.4 years there is a decrease in maximal extensibility that lacks significance for the limited age span examined. On the other hand, the energy loss in length-tension cycling (hysteresis) of alveolar wall increases in aging humans, diminishes in rats and rabbits, and shows little change in horses and monkeys. The breaking force of alveolar wall increases with age in rats and rabbits but does not change significantly in the other species. Of these species, the monkey promises a better model of the age-related changes in maximal extensibility of alveolar wall. A measure of maximal extensibility can distinguish the effects of dilatation of air spaces from those of destruction of alveolar wall in causing loss of lung elastic recoil.
Adolescent↗
Restricted diffusion in biophysical systems: theory.
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Cell Membrane Permeability↗
Restricted diffusion in biophysical systems. Experiment.
The pulsed-gradient spin echo nuclear magnetic resonance (PGSENMR) technique was used to measure restricted diffusion of water in three types of animal tissue: human blood plasma and red cells; rat and rabbit heart; rat and rabbit liver. Characteristic lengths (L) for restriction of diffusion are estimated from dependence on the measuring time. Limitations on the range of observable restrictive lengths (1.5-15 mum) are discussed.The decrease in diffusivity due to 1 mum alumina powder (volume fraction = 0.18) in glycerin/water mixtures agrees with the Wang theory assuming spherical particles and no hydration. The characteristic length (L approximately 4 mum) is larger than the particle size (1 mum) or separation (1.8 mum). Comparison of the diffusivities in tissues at short diffusion times with the Wang theory indicates some bound or trapped water.For packed red blood cells, a restriction (L approximately 2.3 mum) was attributed tothe red cell membrane. A permeability p approximately 0.014 cm/s may be estimated from the decrease in diffusivity. Average values of diffusivity ratio in heart were: 0.36 +/- 0.02 for rat; and 0.26 +/- 0.03 for rabbit; and in liver: 0.25 +/- 0.01 for rat; 0.25 +/- .04 for 10-day old rabbit; and 0.195 +/- 0.03 for 2-yr old rabbit. A restriction (L approximately 2.7 mum) in rat liver probably results from the mitochondria.
Aluminum↗
Fine needle aspiration cytology of thymic carcinoid tumor.
Carcinoid tumors of the thymus are very rare, and their cytologic findings have not been reported previously in English. Retrospective study of fine needle aspiration (FNA) cytologic features in four histopathologically verified thymic carcinoid tumors are described here in detail. The FNA cytology of thymic carcinoids is characterized by predominantly single and some loose clusters of small, round to oval cells with scanty cytoplasm, interspersed with some larger cells with moderate to abundant, granular cytoplasm. The differential diagnosis of the cytologic features between carcinoid tumor and other mediastinal tumors is also discussed.
Adenocarcinoma↗