Evaluation of the completeness of cancer case ascertainment in the Seoul male cohort study: application of the capture-recapture method.

Since the completeness of case ascertainment is directly related to the validity of a study, the evaluation of completeness is an essential feature of a cohort study. To estimate the completeness of cancer case ascertainment during a three year period (Jan. 1, 1993, to Dec. 31, 1995) in which the Seoul Male Cohort was followed up, we applied capture-recapture method. Data were obtained from the cancer registries, medical records and death certificates, with cases identified from each source numbering 103, 105, and 38, respectively. After eliminating duplicate cases, the total number was 141, and by using a log-linear model, the number of cases not detected by any of the three data sources was estimated to be 16. For all cancers, the estimated completeness of follow-up was 89.9%.     

Classification of metaphyseal change with magnetic resonance imaging in Legg-Calvé-Perthes disease

Seventy-eight patients (85 affected hips and 71 unaffected hips) with Legg-Calvé-Perthes disease were included in this study to evaluate the metaphyseal change in radiographs and magnetic resonance imaging (MRI) and to define the type of the metaphyseal cyst according to presence or absence of the epiphyseal involvement. The content of the metaphyseal cyst was evaluated by using T1,T2, proton, and gadolinium-enhanced T1-weighted MRI scans. Among 85 hips, there were no changes in 32 hips, marrow edema in 13 hips, false cyst with epiphyseal involvement in 28 hips, and true cyst without epiphyseal involvement in 12 hips. Granulation tissue was found in the false cysts and water-rich fibrotic tissue was found in the true cysts based on the MRI scans. The metaphyseal change in MRI scans was shown in 71% of groups 3 and 4 and in 35% of groups 1 and 2 according to the Catterall classification, and 52% of group A, 56% of group B, and 86% of group C according to the Herring classification. Of the 30 hips at the avascular stage, 33% showed metaphyseal cyst in MRI scans. Of the 53 hips at the fragmentation stage, 60% showed the metaphyseal cyst.     

Outcome of children with respiratory symptoms without objective evidence of asthma: a two-year, prospective, follow-up study

This study evaluated the outcome of 33 children with asthma-like symptoms without objective evidence of asthma, and the role of certain factors in predicting the development of clinical asthma in these children. Data on symptom histories, lung functions (flow-volume spirometry, free running test and methacholine inhalation challenge test) and atopic sensitization (skin prick tests and markers of eosinophilic inflammation) were collected twice with an interval of 2 y, and the diagnoses were re-evaluated after the follow-up period. Based on the results, it was concluded that one-third of the children with prolonged or recurrent lower airway symptoms, such as cough or wheeze, either have mild asthma or will develop asthma in the near future. Children who had a significant response [≥ 10% fall in forced expiratory volume in 1 s (FEV1)] in the free running test formed a risk group for active asthma, whereas other baseline characteristics seemed not to predict the outcome.     

Randomized trial examining cerebral haemodynamics following artificial or animal surfactant

To determine the effects of animal and artificial surfactants on cerebral haemodynamics, 20 premature babies receiving mechanical ventilation were randomized to receive Curosurf or Exosurf surfactant. Anterior cerebral artery blood flow velocity (CABFV) was measured using Doppler ultrasound before and up to 2 h after treatment. Following animal surfactant there was a rapid reduction in CABFV (median -36%, range -43% to +8%, p < 0:01), whereas artificial surfactant resulted in a slower rise which was less marked (median +20%, range -7% to +62%, p < 0:05). There were no significant changes in blood pressure. Two hours after administration, the oxygenation index (OI) improved significantly only in babies receiving animal surfactant. In this group there was a significant association between the change in CABFV at 1 min and the change in OI at 2 h ( r = 0:66, p < 0:05). Animal surfactant produces rapid improvements in ventilation which are associated with marked alterations in cerebral haemodynamics.     

Airway Reactivity to Bronchoconstrictor and Bronchodilator: Assessment Using Thin-Section and Volumetric Three-Dimensional CT

Objective

To determine the extent to which thin-section and volumetric three-dimensional CT can depict airway reactivity to bronchostimulator, and to assess the effect of different airway sizes on the degree of reactivity.

Materials and Methods

In eight dogs, thin-section CT scans were obtained before and after the administration of methacholine and ventolin. Cross-sectional areas of bronchi at multiple levels, as shown by axial CT, proximal airway volume as revealed by three-dimensional imaging, and peak airway pressure were measured. The significance of airway change induced by methacholine and ventolin, expressed by percentage changes in cross-sectional area, proximal airway volume, and peak airway pressure was statistically evaluated, as was correlation between the degree of airway reactivity and the area of airways.

Results

Cross-sectional areas of the bronchi decreased significantly after the administration of methacholine, and scans obtained after a delay of 5 minutes showed that normalization was insufficient. Ventolin induced a significant increase in cross-sectional areas and an increase in proximal airway volume, while the effect of methacholine on the latter was the opposite. Peak airway pressure increased after the administration of methacholine, and after a 5-minute delay its level was near that of the control state. Ventolin, however, induced no significant decrease. The degree of airway reactivity did not correlate with airway size.

Conclusion

Thin-section and volumetric spiral CT with three-dimensional reconstruction can demonstrate airway reactivity to bronchostimulator. The degree of reactivity did not correlate with airway size.     

Mechanism of the beneficial effects of pentoxifylline during sepsis: maintenance of adrenomedullin responsiveness and downregulation of proinflammatory cytokines

BACKGROUND: Although it is known that pentoxifylline (PTX) produces various beneficial effects during sepsis, it remains unknown whether this agent has any salutary effects on the depressed vascular responsiveness to adrenomedullin (ADM), a novel potent vasodilatory peptide, under such conditions. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP). One hour after CLP, PTX (50 mg/kg body wt) or vehicle (normal saline) was infused intravenously over 90 min. Twenty hours after CLP (i.e., the late, hypodynamic stage of sepsis), the thoracic aorta and small intestine were isolated and preconstricted by norepinephrine. Rat ADM (10(-7) M) was applied, and the percentage of ADM-induced relaxation in the aortic rings and resistance vessels in the small intestine was determined. In addition, plasma ADM was determined by radioimmunoassay and tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1beta, and IL-6 levels were measured by enzyme-linked immunosorbent assay. RESULTS: The percentage of ADM-induced vascular relaxation in the aortic rings and resistance vessels of the isolated gut was significantly reduced 20 h after CLP. Administration of PTX early after the onset of sepsis, however, prevented the decrease in vascular ADM responsiveness at the macro- and microcirculatory levels. Plasma ADM levels increased after CLP, irrespective of PTX infusion, indicating that the effect of PTX was not mediated by altering ADM release. The upregulated TNF-alpha, IL-1beta, and IL-6 during late sepsis were, however, attenuated by PTX administration, suggesting that maintenance of ADM responsiveness by this agent appears to be due to downregulation of these cytokines. CONCLUSIONS: Since early administration of PTX maintains vascular ADM responsiveness even during the late stage of sepsis, this agent appears to be a useful adjunct in preventing the deterioration in hemodynamics and cardiovascular function during the progression of polymicrobial sepsis.     

The important role of the gut in initiating the hyperdynamic response during early sepsis

BACKGROUND: Although the initial response to sepsis includes a hyperdynamic phase and although the increased hepatic perfusion in early sepsis is due solely to the increased portal blood flow, it remains unknown whether the gut plays an important role in producing such a response. MATERIALS AND METHODS: Adult male Sprague-Dawley rats underwent a complete enterectomy (ER) before being subjected to sepsis by cecal ligation and puncture (CLP; the cecum was excised from the removed gut and stitched to the posterior peritoneum in ER groups) or sham operation. At 2 h after CLP (i.e., the early, hyperdynamic phase of sepsis), cardiac output and heart performance (+/-dP/dt(max)), as well as hepatic and renal blood flow, were measured. Systemic and regional oxygen delivery (DO(2)) and oxygen consumption (VO(2)) were also determined. RESULTS: Cardiac output, heart performance, organ blood flow, as well as DO(2) and VO(2), increased significantly 2 h after CLP. ER prior to the onset of sepsis, however, prevented the elevation of those parameters. ER in sham animals did not alter the measured parameters with the exception that portal blood flow decreased by 85% and hepatic arterial blood flow increased by 368%, resulting in no significant reduction in hepatic DO(2) and VO(2). There were no changes in circulating blood volume among groups, indicating that the effect of ER on hemodynamics after CLP was not due to alterations in blood volume. CONCLUSION: Since ER immediately before the onset of sepsis prevents the increase in cardiac output and regional hemodynamics, the gut appears to play an important role in producing the hyperdynamic response during the early stage of polymicrobial sepsis.