Reaction of Macrophages to Cigarette Smoke. II. Immigration of Macrophages to the Lungs

The present study identifies the source of the elevated pulmonary macrophage population in young adult male mice which results when animals are exposed to cigarette smoke. Light microscopic and autoradiographic analysis of pulmonary tissue from smoke-exposed animals revealed that pulmonary macrophages (free, attached, and septal or interstitial) divide only rarely. Further, it was noted that, during the marked progressive increase in the labeled macrophage population in the lungs, the number of silver grains over the nuclei of labeled macrophages did not become significantly diluted. Thus, the markedly elevated macrophage population which results when animals are exposed to cigarette smoke appears, for the most part, to be due to immigration of cells from bone marrow rather than in situ division of resident macrophages.     

The Growth of Radiata Pine On Lateritic Soils at Second Valley,South Australia

Factors involved in the growth of P. radiata (D. Don) on soils of a lateritic landscape have been examined by soil and foliar analysis and the measurement of ring width; this has given an appraisal of factors influencing growth in the past and at the present time.

Perched water tables, which often occurred in winter on the plateau where there were lateritic podzolic soils, did not depress growth. The addition of phosphate was essential, with responses lasting for about 8 years with superphosphate. Regression relationships between the annual growth increment (ΔV in cubic feet) and foliar levels of nitrogen (N) and phosphorus (P) were found for three different foliar sampling positions; these relationships had the form:

ΔV = 4.5%P + 0.28%N—0.47.

Considerable variation was found in the foliar levels of nitrogen, phosphorus, copper, zinc, boron, nickel, molybdenum, chromium and ash for different sample positions within the tree. Preliminary responses to nickel, copper and nitrogen were obtained on 15-year-old trees well supplied with phosphorus. Advisory foliar levels for nitrogen and phosphorus are given.     

Rosiglitazone may reduce thyroid cancer risk in patients with type 2 diabetes

Abstract

Background. Whether rosiglitazone use in patients with type 2 diabetes may affect thyroid cancer risk has not been investigated.

Methods. The reimbursement databases of all diabetic patients under oral anti-diabetic agents or insulin from 1996 to 2009 were retrieved from the National Health Insurance of Taiwan. An entry date was set at 1 January 2006, and 887,665 patients with type 2 diabetes were followed for thyroid cancer incidence until the end of 2009 for ever-users, never-users, and subgroups of rosiglitazone exposure using tertile cut-offs for time since starting rosiglitazone, duration of therapy, and cumulative dose. Hazard ratios were estimated by Cox regression.

Results. There were 103,224 ever-users and 784,441 never-users, with respective numbers of incident thyroid cancer of 84 (0.08%) and 764 (0.10%), and respective incidence of 23.12 and 28.09 per 100,000 person-years. The overall multivariable-adjusted hazard ratio was not significant. However, in dose-response analyses, the adjusted hazard ratios (95% confidence intervals) were significant for the third tertile of duration of therapy (≥ 14 months) and cumulative dose (≥ 1,800 mg) for age ≥ 50 years: 0.53 (0.31–0.89) and 0.50 (0.29–0.87), respectively.

Conclusions. This study suggests that rosiglitazone use in patients with type 2 diabetes may reduce the risk of thyroid cancer.     

The M3S-based electric wheelchair for the people with disabilities in Taiwan

Purpose.?This study aims to establish an electronic wheelchair system in Taiwan that conforms to multiple master–multiple slave (M3S) standards. The proposed system could enhance the safety and convenience of people with disabilities.

Material and method.?The M3S-based head-controlled electric wheelchair consists of three parts: (A) the input device, (B) the output device, and (C) the safety device. Head movement can be used as the input control to cause the tilting device to produce a corresponding level of analog voltage (backward & forward/left & right) which is then transmitted to the analogy/digital conversion module to control the output device (wheelchair's motor). Ten subjects with C5 uncompleted spinal cord injury were recruited in the clinical assessment. They were randomly assigned into groups A and B. In the group A, the subjects were assigned to operate the head-controlled wheelchair system with M3S standard before operating the head-controlled wheelchair system without M3S standard. In the group B, the subjects were assigned to operate the head-controlled wheelchair system without M3S standard before operating the head-controlled wheelchair system with M3S standard. Two subjects in the group B drop off due to their personal reasons.

Results.?The time cost for group A in completing tasks 1, 2, and 3 with the M3S and without the M3S were insignificant (p > 0.05). The time cost for completing in group B was insignificant (p > 0.05). Thus, the wheelchair operating time is depended on the proficiency of the subjects, not the M3S standard added.

Discussions and conclusions.?The time cost for subjects to operate the wheelchair was determined by their proficiency, not the M3S standard control added to the system. However, the M3S-based system did realize the safety mechanism and complex auxiliary tools with and without the plug-in and play function.     

A benchmark dose study of prenatal exposure to di(2-ethylhexyl) phthalate and behavioral problems in children

IntroductionPrenatal exposure to di(2-ethylhexyl) phthalate (DEHP) has been reported to be associated with adverse effects on neurodevelopment that yield behavior syndromes in young children with an estimated median exposure lower than the currently recommended tolerable daily intake (TDI) and reference dose (RfD).ObjectivesOur aim was to derive the benchmark dose for prenatal exposure to DEHP for the neurodevelopmental health in children.MethodsA total of 122 mother-child pairs from the Taiwan Maternal and Infant Cohort Study were analyzed for the dose-response relationship between maternal exposure to DEHP and children's behavioral syndromes evaluated at 8 years (n = 122, 2009), 11 years (n = 96, 2012), and 14 years (n = 78, 2015) of age. We employed a multivariate regression model to assess the statistical associations between the estimated maternal average daily intake of DEHP and child's individual CBCL scores for boys and girls at each separate age, followed by a mixed model for all the children across three ages accounting for individual variations. We then employed structural equation models by combining the children's specific behavioral problem scores at different ages and obtained a simulated overall latent score in relation to maternal exposure. Based on the established dose-response relationship, we derived the benchmark dose (BMD) and the lower limit (BMDL).ResultsAssociations of maternal DEHP exposure (median 4.54$\mu g/kg\_bw/day$) with the Child Behavior Checklist (CBCL) scores were all significant, except for somatic complaints, adjusting for child's age, gender, IQ, and family income. The BMDL, given a benchmark response of 0.10 (0.05) and a background response of 0.05, was 6.01 (2.16) $\mu g/kg\_bw/day$for an integrated CBCL score.ConclusionsThe current TDI (RfD) of 50 (20) $\mu g/kg\_bw/day$ for DEHP might not protect pregnant women for their children from behavioral problems. There remains the lack of comparable toxicological data. Further investigations are needed.