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Brominated flame-retardants (BFRs) are environmental endocrine disruptors, comprising several pollutants, which potentially affect the endocrine system and cause dysfunction and disease. Widespread BFR exposure may cause multisystem toxicity, including cardiovascular toxicity in some individuals. Studies have shown that BFRs not only increase heart rate, induce arrhythmia and cardiac hypertrophy, but also cause glycolipid metabolism disorders, vascular endothelial dysfunction, and inflammatory responses, all of which potentially induce pre-pathological changes in atherosclerosis. Experimental data indicated that BFRs disrupt gene expression or signaling pathways, which cause vascular endothelial dysfunction, lipid metabolism-related disease, inflammation, and possibly atherosclerosis. Considerable evidence now suggests that BFR exposure may be a pro-atherosclerotic risk factor. In this study, we reviewed putative BFR effects underpinning pro-atherosclerosis mechanisms, and focused on vascular endothelial cell dysfunction, abnormal lipid metabolism, pro-inflammatory cytokine production and foam cell formation. Consequently, we proposed a scientific basis for preventing atherosclerosis by BFRs and provided concepts for further research., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background and Objectives: The main target of inspiratory muscle training (IMT) is to improve diaphragm function in patients with COPD who have inspiratory muscle weakness. Ventilatory demand is already increased during quiet breathing in patients with COPD, and whether threshold load imposed by IMT would active more accessory muscle remained to be determined. The purpose of this study was to examine diaphragm and sternocleidomastoid (SCM) activation during IMT with intensities of 30% and 50% maximal inspiratory pressure (P Imax )., Methods: Patients with COPD and a P Imax lower than 60 cmH 2 O were recruited for the study. Surface electromyography (EMG) was used to measure diaphragm and SCM activation, and group-based trajectory modeling (GBTM) was used to identify activation patterns during IMT. The generalized estimating equation (GEE) was then used to detect differences of variables between various breathing tasks. Statistical significance was established at p < 0.05., Results: A total of 30 patients with COPD participated in this study. All patients demonstrated significant increases in diaphragm and SCM activation during 30% and 50% P Imax of IMT than during quiet breathing (all p < 0.001). Diaphragm demonstrated two distinct patterns in response to IMT: low activation (n = 8) and high activation (n = 22) group using GBTM analysis., Conclusion: Diaphragm and SCM were substantially activated during IMT in patients with COPD who had inspiratory muscle weakness. Regardless of whether diaphragm activation was high or low, SCM was activated to a greater extent in response to IMT., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study evaluated the efficacy of slightly acidic electrolyzed water (SAEW) for the inactivation of Salmonella Enteritidis and Escherichia coli on shelled eggs as well as studied the shelf life and internal quality attributes (i.e., weight loss, Haugh unit, yolk index, albumen pH, and yolk pH) of eggs during storage at 25°C. The decontamination test egg samples (freshly laid) were inoculated and immersed for 1, 2, 3, and 4 min in each treatment (i.e., SAEW, acidic electrolyzed water, NaClO solution, and sterile deionized water) at available chlorine concentrations (ACCs) of 10, 18 and 26 mg/L. The storage test eggs (freshly laid) were immersed for 3 min in 4 treatments (i.e., SAEW, acidic electrolyzed water, NaClO solution, and no treatment) and stored for 30 D at 25°C. The effects of the SAEW on microbiological qualities and freshness parameters were investigated. Decontamination of eggs with SAEW showed an equivalent or higher bactericidal effect compared to other treatments. A complete inactivation of S. Enteritidis and E. coli on the surface of shelled egg samples resulted from treatment with SAEW at an ACC of 26 mg/L for 3 and 4 min, respectively. Almost all of the egg quality parameters investigated in the present study were significantly (P < 0.05) affected by the storage time. As storage time increased, the yolk index and Haugh unit value decreased, and weight loss, albumen pH, and yolk pH increased. However, SAEW treatment minimized weight loss (5.52%) and preserved the albumen and yolk quality better than no treatment at 25°C. Relative to acidic electrolyzed water and NaClO solution, the advantages of SAEW are reduced corrosion of egg surfaces and potentially less water and CO2 escaping from eggshell pores. The results highlight the promising use of SAEW to enhance the microbial safety and to extend the shelf life of shelled eggs. Future combined methods with SAEW and other treatments are also needed., (© 2019 Poultry Science Association Inc.)

Background: The time schedules for response evaluation of epidermal growth factor receptor-tyrosine kinase Inhibitor (EGFR-TKI) in non-small cell lung cancer (NSCLC) patients are still ill-defined., Methods: Stage IIIB/IV patients with histologically proven NSCLC were enrolled in this study if the tumor cells bore EGFR mutations other than T790M. Eligible patients were treated with either 250 mg of gefitinib or 150 mg of erlotinib once daily. The early response rate [computed tomography (CT) scan on Day 14], definitive response rate determined on Day 56, progression-free survival (PFS), overall survival (OS), and toxicity profile were assessed prospectively., Results: Thirty-nine patients were enrolled in this study. A total of 29 patients (29/39, 74.4%) achieved partial response (PR). Twenty-one patients (21/39, 53.8%) had early radiological response on Day 14. The early radiological response rate in patients with PR was 72.4% (21/29). Only eight patients without a PR on early CT still ended with PR. Among the 29 patients with PR, the PFS (8.1 months) and OS (18.3 months) of the 21 patients with early CT response were shorter than those of the 8 patients without early CT response (11.9 and 24.0 months for PFS and OS, respectively). But the survival differences were statistically non-significant., Conclusions: A very high percentage (72.4%, 21/29) of NSCLC patients with EGFR mutations with PR demonstrates early radiological response to EGFR-TKIs, which would advocate early radiological examination for EGFR-TKI therapy in NSCLC patients.

The purpose of this in vivo study was to evaluate the effect of human dental pulp stem cells (hDPSCs) on various resorbable calcium sulfate/calcium phosphate bone grafts in bone regeneration. Granular particles of calcium sulfate dehydrate (CSD), α-calcium sulfate hemihydrate/amorphous calcium phosphate (α-CSH/ACP), and CSD/β-tricalcium phosphates (β-TCP) were prepared for in vitro dissolution and implantation test. The chemical compositions of specimen residues after dissolution test were characterized by XRD. The ratios of new bone formation for implanted grafts/hDPSCs were evaluated using mandible bony defect model of Lanyu pig. All the graft systems exhibited a similar two-stage dissolution behavior and phase transformation of poor crystalline HAp. Eight weeks post-operation, the addition of hDPSCs to various graft systems showed statistically significant increasing in the ratio of new bone formation (p<0.05). Null hypothesis of hDPSCs showing no scaffold dependence in bone regeneration was rejected. The results suggest that the addition of hDPSCs to calcium sulfate based xenografts could enhance the bone regeneration in the bony defect., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Ethnic differences exist in the function and distribution of adipose tissue, which influences whole body metabolism, including pulmonary function. The object of this study was to examine the relationships between serum metabolic parameters and pulmonary function in a morbidly obese Asia-Pacific population., Methods: One-hundred thirty-seven morbidly obese Chinese patients, aged≥18 years with a body mass index (BMI)>32 kg/m(2) who were being evaluated for bariatric surgery between July 2007 and December 2008, were studied. Cross-sectional associations between serum metabolic parameters, including lipids, glucose, insulin, leptin, and adiponectin levels with forced vital capacity (FVC) and forced expiratory volume in the first second (FEV₁) assessed by spirometry, were analyzed. Multiple regression analyses also were conducted, with age, gender, smoking history, and various anthropometric measurements of obesity as confounders., Results: Serum adiponectin and HDL cholesterol had a positive correlation with FVC and FEV1. In addition, insulin resistance, determined by the homeostatic model assessment method (HOMA), was negatively correlated with FVC. In the multiple linear regression analysis, only serum adiponectin was significantly correlated with FVC and FEV₁, independent of obesity level., Conclusions: Serum adiponectin level was positively and independently associated with pulmonary function in morbidly obese Chinese adults., (Copyright © 2014 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Introduction: Recently, two studies revealed that MET amplification was associated with secondary epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) resistance in non-small cell lung cancer (NSCLC) patients. But it remains uncertain whether MET amplification could be related to primary TKI resistance in NSCLC because of limited data., Materials and Methods: MET gene dosage of the tumor tissues from 208 NSCLC patients was investigated by real time quantitative polymerase chain reaction and compared with molecular and clinical features, including EGFR mutations, KRAS mutations, EGFR gene copy numbers, and patient survivals. Three copies were used as the cutoff. Among them, 25 patients were also evaluable for EGFR TKI responsiveness., Results: The proportion of high MET gene dosage was 10.58% (22/208) with higher incidence in squamous cell carcinoma (11.86%) and smokers (16.18%), although the differences with adenocarcinoma and nonsmokers were nonsignificant. Coexisting EGFR mutations were identified, and the incidence (8.54%) was similar to wild type (12.0%). High MET gene dosage was significantly associated with higher tumor stage (stage I + II versus stage III + IV; p = 0.0254) and prior chemotherapy for stage III + IV adenocarcinoma patients (35.71% versus 7.41%; p = 0.0145) but not correlated with primary TKI resistance. Among the 155 surgically resectable patients (stage I to IIIA), high MET gene dosage was significantly associated with shorter median survival (21.0 months versus 47.1 months; p = 0.042) by univariate analysis., Conclusions: High MET gene dosage was not related to primary TKI resistance and the incidence was increased after chemotherapy, suggesting high MET gene dosage may also be related to chemotherapy resistance.

Background: Obesity is associated with impaired pulmonary function. We evaluated the effect of bariatric surgery on pulmonary function among obese patients and identified potential anthropometric factors of obesity corresponding to the reversal of impaired pulmonary function., Methods: Pulmonary function and anthropometric factors were studied in 94 obese patients aged 18-65 years with a body mass index >32 kg/m(2). Pulmonary function tests were performed preoperatively and 3 months after bariatric surgery. The measurements included forced vital capacity (FVC), forced expiratory volume in the first second (FEV(1)), total lung capacity, expiratory reserve volume, residual volume, and diffusing capacity of the lung for carbon monoxide. The anthropometric factors included the body weight, body mass index, waist circumference (WC), hip circumference, waist/height ratio, and waist/hip ratio. The changes in anthropometric parameters were analyzed in relation to pulmonary function test results. Multiple linear regression models were applied to identify the factors that influenced pulmonary function after bariatric surgery., Results: When measured 3 months after surgery, all anthropometric parameters for the 94 patients studied had significantly decreased, and the pulmonary function test parameters had significantly improved. Of the anthropometric parameters, the reduction in body weight, WC, and waist/height ratio correlated significantly with increases in the FEV(1) and FVC. In the multiple linear regression analysis, only the reduction in WC correlated significantly with the reductions in the FEV(1) and FVC., Conclusion: After bariatric surgery, all anthropometric parameters of obesity decreased significantly and the pulmonary function improved. This improvement correlated best with the reduction in the WC and perhaps a decreased intra-abdominal pressure., (Copyright © 2011 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Introduction: The objective of this study was to investigate the antibacterial, biocompatibility, and mechanical properties of mineral trioxide aggregate (MTA) set using a calcium lactate gluconate (CLG) solution., Methods: ProRoot white MTA (WMTA) (Dentsply Tulsa Dental, Tulsa, OK) was used as the control group; MTA-like cement was prepared by mixing Portland cement/bismuth oxide/calcium sulfate (75/20/5) as the experiment group. A solution of 23.1 wt% CLG was used as a hydration accelerant and was compared with deionized water (DDW). Changes in pH values, antibacterial properties, in vitro cell viability, and diametral tensile strength (DTS) of the hydrated cements were assessed., Results: Like WMTA, pH values for the MTA-like cement set using DDW and the CLG solution showed minor but statistically significant differences (P < .05). The antibacterial effects of hydrated specimens set by DDW and CLG against Streptococcus mutans assessed with an in vitro tube dilution test showed a significant difference in the early hydration time but no significant difference after 60 minutes (P > .05). A mouse osteoblastic cell (MC3T3-E1)-based MTT assay revealed that WMTA set using CLG had significantly higher cell viability than that set using DDW (P < .05). The DTS test for hydrated MTA-like cement with different liquids showed a significant difference on day 1 but no statistical difference on day 21., Conclusions: The results suggest that using a CLG solution as the hydration accelerant may enhance the biocompatibility but not compromise WMTA's antibacterial and mechanical properties., (Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: The present study aimed to investigate the trends in changes in pulmonary function and the risk factors for pulmonary function deterioration in patients with pulmonary tuberculosis after completing treatment., Introduction: Patients usually have pulmonary function abnormalities after completing treatment for pulmonary tuberculosis. The time course for changes in pulmonary function and the risk factors for deterioration have not been well studied., Methods: A total of 115 patients with 162 pulmonary function results were analyzed. We retrieved demographic and clinical data, radiographic scores, bacteriological data, and pulmonary function data. A generalized additive model with a locally weighted scatterplot smoothing technique was used to evaluate the trends in changes in pulmonary function. A generalized estimating equation model was used to determine the risk factors associated with deterioration of pulmonary function., Results: The median interval between the end of anti-tuberculosis treatment and the pulmonary function test was 16 months (range: 0 to 112 months). The nadir of pulmonary function occurred approximately 18 months after the completion of the treatment. The risk factors associated with pulmonary function deterioration included smear-positive disease, extensive pulmonary involvement prior to anti-tuberculosis treatment, prolonged anti-tuberculosis treatment, and reduced radiographic improvement after treatment., Conclusions: After the completion of anti-tuberculosis TB treatment, several risk factors predicted pulmonary function deterioration. For patients with significant respiratory symptoms and multiple risk factors, the pulmonary function test should be followed up to monitor the progression of functional impairment, especially within the first 18 months after the completion of anti-tuberculosis treatment.

Introduction: The prognostic role of epidermal growth factor receptor (EGFR) mutations in patients with surgically resectable non-small cell lung cancer (NSCLC) without EGFR tyrosine kinase inhibitor treatment has not been well established, because the reports are still few., Materials and Methods: We analyzed the survival data of 164 patients with surgically resectable (stages I to IIIA) NSCLC of two year groups (1996-1998 and 2002-2004), and compared with EGFR mutations, KRAS mutations, and EGFR gene copy numbers., Results: Comparing the survival of wild-type patients and patients having L858R mutations or exon 19 deletion, the median survival was much longer for patient with EGFR mutations (54.7 months) than wild type (34.9 months). The difference was not statistically significant by univariate analysis (p = 0.1981) but had borderline significance by multivariate analyses (p = 0.0506). In addition, the 3-year survival rates of patients with EGFR mutations were also significantly higher than wild type (p = 0.0232). After exclusion of 18 patients treated by EGFR-tyrosine kinase inhibitor for tumor recurrence, the trends were still the same. Patients with KRAS mutations had shorter median survival (21 months) than wild type (44.4 months). Patients with EGFR polysomy (>==copies) also had longer median survival (56.2 months) than wild type (53.4 months). But the survival differences of these two genetic markers were all not significant statistically., Conclusion: It is intriguing that patients with NSCLC with EGFR mutations had better survival than wild type. Such a tumor biology may confound the survival data in a study without the stratification by EGFR mutation.

Background: Congenital central hypoventilation syndrome (CCHS) is characterized by compromised chemoreflexes resulting in sleep hypoventilation. We report a Chinese family with paired-like homeobox 2B (PHOX2B) mutation-confirmed CCHS, with a clinical spectrum from newborn to adulthood, to increase awareness of its various manifestations., Methods: After identifying central hypoventilation in an adult man (index case), clinical evaluation was performed on the complete family, which consisted of the parents, five siblings, and five offspring. Pulmonary function tests, overnight polysomnography, arterial blood gas measurements, hypercapnia ventilatory response, and PHOX2B gene mutation screening were performed on living family members. Brain MRI, 24-h Holter monitoring, and echocardiography were performed on members with clinically diagnosed central hypoventilation., Results: The index patient and four offspring manifested clinical features of central hypoventilation. The index patients had hypoxia and hypercapnia while awake, polycythemia, and hematocrit levels of 70%. The first and fourth children had frequent cyanotic spells, and both died of respiratory failure. The second and third children remained asymptomatic until adulthood, when they experienced impaired hypercapnic ventilatory response. The third child had nocturnal hypoventilation with nadir pulse oximetric saturation of 59%. Adult-onset CCHS with PHOX2B gene mutation of the + 5 alanine expansions were confirmed in the index patient and the second and third children. The index patient and the third child received ventilator support system bilevel positive airway pressure treatment, which improved the hypoxemia, hypercapnia, and polycythemia without altering their chemosensitivity., Conclusions: Transmission of late-onset CCHS is autosomal-dominant. Genetic screening of family members of CCHS probands allows for early diagnosis and treatment.

To explore the relationship of self-reported exposure to tobacco smoke and the cotinine levels in the urine and blood over the follow-up period for pregnant women. Three hundred ninety-eight pregnant women undergoing prenatal care were interviewed in different trimesters at three hospitals in central Taiwan using a structured questionnaire. Based on their self-reported smoking experience, the participants were classified into three groups (25 smokers, 191 passive smokers, and 182 non-smokers) and were tracked in this study up to the time of delivery. Cotinine levels were tested for the maternal blood and urine at the end of each trimester and for the umbilical cord-blood of the newborns. All specimens were measured using a sensitive high-performance liquid chromatographic (HPLC) technique. In general, urinary cotinine levels were higher in subjects who smoked (including current- and ex-smokers) than those who never smoked. The pattern of distribution of cotinine levels among smoking/ETS exposure group in the urine sample was similar to that in the blood sample. The umbilical cord-blood cotinine levels was found to be highest in the active smoking group, followed by the ETS group exposed to ETS both at home and in the workplace. Over the course of the pregnancies, there was an increase in cotinine levels in urine and maternal blood for each of 3 exposure groups. Exposure to smoking by self-reported information in pregnant women has been found to be directly related to the levels of cotinine in the umbilical cord-blood of the fetus. Cotinine is a sensitive measure of ETS exposure, but if biochemical analysis is not available or convenient for a pregnant woman, then self-reported exposure to ETS can provide a good estimate if the information is gathered by a well-trained interviewer in a structured way.

Purpose: The objective of this study was to differentiate the magnetic resonance (MR) imaging appearance of benign peripheral nerve sheath tumors (PNSTs) from that of malignant PNSTs., Materials and Methods: Twenty-six patients who underwent MR imaging and had a histologic diagnosis of benign (schwannoma, n=16; neurofibroma, n=1) or malignant (n=9) PNST were retrospectively reviewed. The size, location, shape, margin, and signal intensities of the tumors on precontrast and gadolinium-enhanced MR imaging were analyzed. In each patient, the presence or absence of split fat, target, and fascicular signs was determined., Results: The mean size of the benign PNSTs (3.4 cm, S.D.=2.5 cm) was significantly smaller than that of the malignant tumors (8.2 cm, S.D.=3.1 cm) (P<.001). Seventeen (65.4%) of the 26 tumors were spindle shaped or ovoid (12 benign and 5 malignant tumors). Contiguity with specific nerves was identified in 15 (88.2%) of the 17 benign PNSTs but in none of the malignant tumors (P<.05). Well-defined margins were noted in all 17 benign PNSTs but in only 3 (33.3%) of the 9 malignant tumors (P<.001). Five (55.6%) of the 9 malignant PNSTs but none of the benign tumors showed signal intensity change in adjacent soft tissue (P<.05). There was no significant difference in signal intensity between the benign and malignant tumors on T(1)-weighted, T(2)-weighted, and contrast-enhanced MR images. The split fat and target signs were present more frequently in the benign PNSTs than in the malignant PNSTs (P<.05)., Conclusions: Benign and malignant PNSTs are often spindle shaped. Recognition of contiguity with adjacent nerves, a well-defined margin, and the presence of the split fat sign may suggest benignity. Imaging features suggestive of malignancy can be a larger size and an infiltrative margin.

This study determined the effects of environmental tobacco smoke (ETS) on fetal growth by measuring neonatal birth outcomes and the extent of maternal DNA damage, and investigating the relationships among gene polymorphisms, genotoxicity, and pregnancy outcomes of expectant mothers who had exposed to tobacco smoke. This prospective study enrolled 685 pregnant women who completed an initial questionnaire at three central Taiwan hospitals between 2003 and 2004. Genotype analyses of CYP1A1, GSTT1, GSTM1, and NAT2 were performed from 421 women. A total of 398 women completed the follow-up analysis and successfully delivered a live single baby (n=384). Comet assay was performed for 18 smokers, 143 ETS-exposed subjects and 130 non-smokers to measure DNA damage. Analytical findings indicated that the levels of DNA damage among smokers and ETS-exposed subjects were significantly higher than that of non-smokers. DNA damage score in the ETS-exposed group was 84.3+/-44.3 and 63.5+/35.0 [corrected] for the nonsmoking group (p<0.001). Risk of DNA damage (DNA strand breakage, sister chromatid exchange, cell transformation and escalation of cytotoxicity) for subjects exposed to ETS was 7.49 times (adjusted odds ratio; 95% CI, 1.27-44.20) [corrected] greater than that of non-exposed to tobacco smoke at home. Average birth weight of neonates born to subjects with extremely serious DNA damage (within the 90th percentile, DNA damage score >or =129.5) was 141 g lighter than that of those with DNA damage score <129.5 (p=0.068) [corrected] The degree of DNA lesion was not related to metabolic polymorphic genes. The results of this study suggest that comet assay are reliable biomarkers for monitoring pregnant women exposed to tobacco smoke and indicate fetal growth effects from environmental exposure to tobacco smoke.

Introduction: The diaphragm plays a pivotal role in weaning and successful extubation. We hypothesized that ultrasonographic evaluation of the movements of the diaphragm by measuring liver/spleen displacement during spontaneous breathing trials is a good predictor for extubation outcome., Patients and Methods: The studied subjects were intubated patients receiving mechanical ventilation who were scheduled to be extubated. The displacement of liver/spleen was measured by ultrasonography before extubation. The patients were classified into a success group (SG) or failure group according to the extubation outcome. The baseline data and organ displacements in these two groups were analyzed. The sensitivity and specificity for the mean organ displacements and weaning parameters to predict successful extubation were calculated., Results: We included 55 patients, 32 of whom (58%) were in the SG. The baseline data are similar for these two groups, but the mean values of liver and spleen displacements were higher in the SG. Using a cutoff value of 1.1 cm, the sensitivity and specificity to predict successful extubation were 84.4% and 82.6%, respectively, better than traditional weaning parameters in this study., Conclusion: The displacement of the liver/spleen, measured by ultrasonography, is a good predictor for extubation outcome.

Study Objectives: To examine the value of negative expiratory pressure (NEP) in the assessment of methacholine bronchoprovocation testing (BPT)., Design: Prospective, observational study., Setting: Pulmonary function laboratory in a university hospital., Participants: Fifty-nine patients with chronic cough referred from outpatient clinics for methacholine BPT., Methods: Each subject inhaled successive doubling concentrations of methacholine (from 0.049 to 25 mg/mL) until the FEV(1) decreased for > 20% or the maximum concentration of methacholine was inhaled. NEP was measured in the sitting position during tidal breathing before and after methacholine BPT. The FEV(1) and forced oscillation airway resistance (Rrs) and interrupter airway resistance (Rint) were also obtained simultaneously. A positive BPT result was defined as a fall in FEV(1) > or = 20%., Result: At baseline, only five patients had expiratory flow limitation as demonstrated by NEP (EFL-N). There were 39 patients with positive BPT results, and the other 20 patients had negative results. Among the BPT-positive patients, only 13 patients (33.3%) had EFL-N after methacholine challenge. The sensitivity indexes (absolute change/SD) of FEV(1), NEP, Rrs, and Rint were 16.0 +/- 9.6%, 1.1 +/- 1.6%, 3.8 +/- 4.5%, and 5.89 +/- 4.4% (mean +/- SD), respectively. The percentage changes in FEV(1) in BPT-positive patients correlated with the percentage changes in Rrs (r = 0.419, p = 0.008) and only marginally with the percentage changes in Rint (r = 0.307, p = 0.058), but not with the changes in EFL-N (r = 0.048, p = 0.77)., Conclusion: These data suggest that NEP at sitting position is not sensitive in the assessment of methacholine bronchoprovocation as compared to FEV(1) and airway resistance measurements.

Study Objectives: Despite the recognition that ventilator weaning is associated with a change in autonomic nervous system activity, there has not been any report concerning the change of heart rate variability (HRV), a reliable method to detect autonomic nervous system activity, in patients during weaning. The aim of this study was to investigate the change of autonomic nervous system activity during ventilator weaning by HRV analysis., Design: Prospective study., Setting: A 16-bed medical ICU of a tertiary university hospital., Patients: Twenty-four patients receiving mechanical ventilation were included. Twelve patients with successful extubation after a spontaneous breathing trial (SBT) [T-piece trial] were classified as the success group; otherwise, the patients were placed in the failure group., Interventions: None., Measurements and Results: Variables, including the total power (TP), and the high-frequency (HF) and low-frequency (LF) components of HRV, were measured in three phases: assist/control mandatory ventilation, pressure support ventilation (PSV), and SBT. While shifting from PSV to SBT, the HRV components decreased significantly in the failure group (TP, p = 0.025; LF, p = 0.007; HF, p = 0.031), but not in the success group., Conclusions: By HRV analysis, reduced HRV and vagal withdrawal of the autonomic nervous system activity are the main changes in patients with weaning failure.

We report the successful application of high-frequency oscillatory ventilation in a patient with tension pneumatocele (TP). The proposed check-valve mechanism for the development of pneumatoceles predicts that positive-pressure ventilation could lead to distension of these airspaces and formation of TPs. Therefore, high-frequency ventilation could be more applicable in conditions, such as massive air leak due to bronchopleural fistula, that are difficult to manage by conventional ventilator modes.

Ultrasound (US) and magnetic resonance imaging (MRI) of 422 cases were evaluated to compare the feasibility in diagnosing full-thickness rotator cuff tears (FTRCTs). On the basis of different US performers, they were divided into two groups: Group 1 performed by a 5-year experience technician and Group 2 performed by a 10-year experience radiologist. Sensitivity, negative predictive value (NPV), accuracy of US, and correlation between the two modalities were better in Group 2. When an expert is available, US can be used for diagnosing FTRCTs; otherwise, MRI should be performed.

The objective of this study was to assess the relationship between blood-lead levels (BLL), hematological, liver and renal indicators among workers in a lead battery factory in Taiwan over a 10-year period. Blood samples were taken periodically from 30 workers and BLL, HGB (hemoglobin), RBC (red blood cells), WBC (white blood cells) and HCT (hematocrit) were measured. Levels of GPT (alanine aminotransferase) and Crea (creatinine) in the blood were assessed to indicate liver and renal function, respectively. The results showed that there was a general decrease in BLL over the 10-year period (except for 1993). There was a similar trend for HCT, RBC and Crea. There was no significant trend for the other health indicators. Four generalized estimating equation (GEE) models [correlation model (A), threshold correlation model (B), instant change model (C) and lag change model (D)] were set up to demonstrate the causal relationship between BLL and the other health indicators. Models A and C showed that BLL correlated positively with RBC, but negatively with Crea. Model B showed that BLL correlated positively with GPT. There were no significant correlations of BLL with the other indicators. Models C and D, (GEE with logit link function to analyze the association between changes BLL and the other health indicators) showed that when BLL increased, RBC and HCT increased, both longitudinally and cross-sectionally. The authors conclude that long-term exposure to lead stimulates production of RBC and HCT, but the effect on liver and renal function was unclear.

The arterial grafts currently in use are classified into five basic categories; 10 different commercially available prostheses were chosen to represent these categories. The Vascutek and Bionit are made from knitted Dacron and have medium porosity, requiring preclotting by the surgeon. The DeBakey Soft Woven and Plasma TFE grafts are made from woven Dacron and have low porosity, not requiring preclotting under most circumstances. Also studied were woven and knitted grafts with leakage resistance referred to as "impervious" Dacron grafts: the Vascutek Gelseal, the Bard Albumin Coated DeBakey Vasculour II, the Microvel with Hemashield, and the albumin saturated, autoclaved DeBakey Soft Woven graft. Gore-Tex and Impra are expanded polytetrafluoroethylene grafts which do not require preclotting. For each type, five grafts 6 cm long and 8 mm in diameter were implanted in the descending thoracic aorta of healthy adult dogs for 16 weeks. The physical characteristics, biocompatibility, and healing patterns varied according to the structure and treatment of the grafts. Pretreatment with biomaterials during manufacture is quite effective in preventing transinterstices blood loss during implantation, but results in altered physical qualities, increased thrombogenicity and delayed healing in comparison to the effects of preclotting with autogenous blood at the time of implantation.

Longitudinal elasticities of whole human blood clot, whole canine blood clot, Factor XIII cross-linked fibrin, glutaraldehyde-fixed human albumin, and formaldehyde-fixed collagen, gelatin and collagen/gelatin were determined and normalized to human whole blood clot. Matrices of a knitted Dacron graft were then impregnated with albumin, collagen, and collagen/gelatin and their longitudinal elasticities were determined and normalized to a preclotted graft. Comparisons were also made for the longitudinal elasticities of a virgin graft, a manipulated control for a preclotted graft, and a manipulated control for the matrix-impregnated grafts. Flexibilities were then calculated based on the weights and elasticities of these grafts and normalized to the flexibility of the preclotted graft. Fibrin had twice and 39 times more longitudinal elasticity than human blood clot and collagen, respectively. The preclotted graft has longitudinal elastic properties similar to a virgin graft, and is 2.8, 2, and 1.4 times more elastic than the albumin, collagen and collagen/gelatin grafts, respectively. The preclotted graft was 2.5, 2, and 1.4 times more flexible than the albumin, collagen and collagen/gelatin grafts, respectively.

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.

This study was designed to determine if the adventitial vasa vasorum contribute to re-endothelialization of the canine carotid artery after removal of the endothelial flow surface. Casting studies demonstrated that vasa vasorum are present only in the adventitia of the canine carotid artery. Ninety autograft segments of the carotid artery from which the endothelium had been removed were implanted in both carotid arteries of 45 dogs. Glutaraldehyde-processed canine carotid allografts were positioned at each end to prevent pannus ingrowth and a Gore-Tex wrap to prevent periarterial tissue growth was placed into the outer wall. Three methods were used, with observations at 4 and 8 weeks. In method 1 the test segment was treated with superficial endarterectomy. In method 2 a balloon catheter was used to remove the endothelium. In method 3 balloon catheter denudation of the flow surface was also employed and, in addition, the adventitia was removed surgically as completely as possible, although a few vasa vasorum were shown to remain in some grafts. In method 1 all the patent endarterectomized arteries were partially re-endothelialized at both the 4- and 8-week intervals. In method 2, 72% of the balloon-denuded patent arteries with intact adventitial vasa vasorum were partially re-endothelialized at 4 weeks and 84% at 8 weeks. However, in method 3 the flow surfaces had no endothelium at 4 weeks and 83% still had none at 8 weeks. These findings suggest that, in the absence of pannus ingrowth, re-endothelialization of the canine carotid artery depends on not only the presence but also the number of adventitial vasa vasorum.

This paper compares the healing of supported knitted Dacron prostheses implanted in the descending thoracic aorta and in the subcutaneous carotid-femoral positions in each of 10 dogs. The descending thoracic aorta prostheses were 6 cm long and the carotid-femoral prostheses averaged 76 cm in length. The healing of four porous clinical axillofemoral grafts is compared to that of the experimental carotid-femoral grafts. There was little similarity between the healing observed in the descending thoracic aortic and subcutaneous positions; the descending thoracic aorta grafts healed rapidly and completely by eight weeks, with thrombus-free flow surfaces covered with confluent endothelial cells. However, the inner wall of the carotid-femoral grafts remained largely unhealed at one year, with endothelialization largely confined to a limited pannus ingrowth across the anastomoses. This indicates that the implant site in the dog is a primary determinant of the rapidity and completeness of healing. The clinical axillofemoral grafts explanted after 20 months to six and one-half years exhibited healing characteristics that were similar to those seen in the carotid-femoral position in the dog. These findings suggest that valid comparisons of interspecies healing require data obtained from similar implant locations. They present a challenge to the previously held concepts of major interspecies differences in speed and extent of tissue ingrowth based on data obtained from noncomparable implant sites.

A new carotid-femoral experimental model has been developed which has significant clinical relevance to human limb salvage bypass grafting in the areas of graft length, hemodynamics and tissue environment. More significantly, the graft healing pattern observed with this model is similar to what is seen in humans. Therefore, this experimental model provides a challenging and critical site for dynamic healing studies and comparisons of different types of vascular prostheses.

To study the therapeutic effects of 3 mg/kg aspirin given at the time of surgery and postoperatively, Dacron carotid grafts with an internal diameter of 4 mm and a length of 6 cm were implanted bilaterally in mongrel dogs. Sixteen control grafts in eight subjects and 20 grafts in 10 subjects treated with aspirin were followed by serial angiograms until consecutive studies showed stable patency rates in both groups. Platelet aggregations, malondialdehyde production, serum salicylate levels, and thromboxane A2 and prostacyclin secretion (measured as thromboxane B2 and 6-keto-prostaglandin F1 alpha) were monitored prior to and throughout the experiment. Surface mapping, indium-111 uptake, factor VIII-related antigen staining, and scanning and transmission electron microscopy were performed on the grafts at sacrifice. This study demonstrates a protective effect on the early patency of small-caliber prostheses in the canine model with daily oral aspirin administration. The degree and duration of this effect depends on the preoperative baseline ratio of thromboxane to prostacyclin in each subject.

Long-term follow-up data from several leading centers concerning patients undergoing coronary artery bypass clearly demonstrate the superiority of the internal mammary artery (IMA) with patency rates of 83 to 94% at 7 to 12 years compared with the saphenous vein and its patency rates of 41 to 53%. Our experimental studies provide a biological basis for understanding this difference. Thin-walled arterial autografts undergo no histological change after being implanted in the arterial system, while venous autografts undergo major changes with an initial scattered loss of endothelium and marked thickening due to a proliferative reaction. The challenge to the cardiac surgeon is to revascularize the entire left ventricle with the IMAs. We have found this possible in most patients with advanced three-vessel disease by using both IMAs either as in situ grafts or free grafts with as many sequential anastomoses as necessary to achieve full revascularization. Our use of the term in situ refers to the graft's origin from the subclavian artery as opposed to a free IMA graft arising from another site.

The process of reendothelialization was studied in a deendothelialized 3 cm segment of the canine descending thoracic aorta from which peripheral endothelial cell ingrowth had been prevented by impervious prosthetic graft sleeves. Three preparations were studied: (1) removal of only the endothelial cells, accomplished by flow surface drying and balloon catheter denudation, (2) removal of the superficial portion of the nonvasal media, accomplished by endarterectomy to a depth of 200 to 300 micron, and (3) removal of the entire inner (nonvasal) media, accomplished by endarterectomy to a depth of 500 to 600 micron to reach the outer (vasal) media. A total of 44 specimens were studied after implantation periods of 7, 14, 28, and 56 days. In all cases endothelial cell ingrowth from the host aorta into the test specimen was prevented by the impervious graft sleeves. In the deep endarterectomy group there were scattered areas of reendothelialization at 1 week, extensive reendothelialization at 2 weeks, almost complete reendothelialization at 4 weeks, and confluence by 8 weeks. However, in the superficial endarterectomy group scanning electron microscopy showed scattered areas of factor VIII/von Willebrand factor (FVIII/vWF)-negative, endothelial-like cells at 4 weeks, whereas at 8 weeks most of the surface was covered by endothelial cells identified by FVIII/vWF. In those specimens subjected to balloon catheter removal of endothelial cells only, reendothelialization was not seen, even at 8 weeks.

This study was designed to establish the influence of the recipient's thrombotic potential on the patency of small-caliber prostheses and to evaluate the subsequent improvement of graft performance by medicinally altering the prostaglandin balance in subjects predisposed to graft occlusion. Mongrel dogs were pretested and classified as low and high responders according to their thrombotic potential, measured as prostaglandin metabolite balance and platelet aggregability. High responders were randomly divided into two groups. Those assigned to serve as the medicated subjects were pretreated 1 week before surgery with a single oral daily administration of combined dazmegrel (UK-38,485) and aspirin in equal dosages of 3 mg/kg. Medication was continued throughout the experiment. Dacron grafts were implanted bilaterally in the carotid artery site in all subjects. Following a 3-week implantation period, the patency rate for the group with low thrombotic potential was 100%. In the animals with high thrombotic potential the patency rate was 10% for nonmedicated subjects and 100% for medicated subjects. These data support the concept that the thrombotic potential largely determines the capacity of the recipient's blood to thrombose small-caliber prostheses. Effective medicinal alteration of prostaglandin balance results in exceptionally increased patency of synthetic grafts.

The effects of tissue ingrowth on the compliance of porous Dacron grafts were studied in 8 mm external-velour warp-knit Dacron grafts implanted in the canine descending thoracic aorta. The compliance of these grafts was measured before implantation and after implant periods of two weeks and one, two, four, and six months. Compliance, which initially was 0.043 +/- 0.008% mm Hg, decreased less than 10% after implantation (no statistical difference at p less than 0.05). No anastomotic neointimal hyperplasia was observed. Although the total thickness of the graft wall increased two- to three-fold after implantation, the benign healing process observed in this study had very little influence on graft compliance followed to six months.

Dacron prostheses with differing degrees of inner wall filamentousness were implanted in the canine descending thoracic aorta for 56 days (n = 14) and the carotid arteries for 21 days (n = 40). In the thoracic aorta the healed inner capsule of 8 mm internal velour grafts was approximately three times as thick as the inner capsule of external velour knitted prostheses. However, the early patency and rapidity of healing of these two types of prostheses were essentially the same. In the carotid arteries the patency of the 4 mm external velour prostheses was greater than that of the internal velour prostheses and the mean thrombus-free surface area of the external velour grafts was significantly greater than that of the internal velour grafts. These observations suggest that an internal velour surface is not deleterious to early patency in a large-caliber, high-flow artery but that it may be in a small-caliber, low-flow artery.

Eight currently used arterial prostheses with differing constructions and materials were implanted in the descending thoracic aorta of mongrel dogs. The prostheses were Gore-Tex (polytetrafluoroethylene), DeBakey Woven, Cooley Woven, Meadox Woven Double Velour, Cooley Knitted Double Velour, Microvel, Vasculour II, and Bionit II. Five series of these eight prostheses were serially implanted in heparinized subjects. During the 40 implantations, attention was focused on three major characteristics: preclotting efficiency, surgical handling characteristics, and healing. Gore-Tex is impervious to blood. The DeBakey and Cooley woven grafts are nearly so. The remaining prostheses required preclotting. The Meadox Woven Double Velour became impervious after two preclotting steps, the Cooley Knitted Double Velour and the Bionit II required three, and the Vasculour II and the Microvel required four. The surgical handling characteristics of the knitted prostheses clearly surpassed those of the DeBakey and Cooley woven and Gore-Tex prostheses. Although the Meadox Woven Double Velour prosthesis had better conformability than the nonveloured woven, the tendency of its cut edge to fray was more pronounced. Healing was much more advanced in the knitted and woven prostheses than in the Gore-Tex.