Urinary antimony in infancy

OBJECTIVE: To determine whether antimony may be detected in the urine during infancy and early childhood and its association with passive exposure to tobacco smoke, as assessed by urinary cotinine. DESIGN: Analysis of spare aliquots of urine collected from infants participating in studies of respiratory function and passive smoking. Urinary antimony was assayed using inductively coupled plasma mass spectroscopy in 201 urine specimens collected at different ages throughout the first two years of life from 122 term and 26 preterm infants. Urinary cotinine was measured using gas liquid chromatography. MAIN OUTCOME MEASURE: Urinary antimony concentrations. RESULTS: Absolute antimony concentrations varied widely between infants, being below the laboratory detection limit of 0.02 microgram/l in 7% of samples, below 0.5 microgram/l in 90.5%, and above the reference value of 1 microgram/l reported for non-occupationally exposed UK populations in 4%. Creatinine standardised antimony values were unrelated to postnatal age or urinary cotinine concentrations and were highest in urine collected from preterm infants within 24 hours of birth (geometric mean (95% confidence interval): 2.3 ng/mg (1.5 to 3.4)). CONCLUSIONS: Although antimony is present at very low concentrations in urine during infancy and early childhood, the relevance to health is uncertain. The higher levels found in preterm infants may reflect prematurity or fetal assimilation of antimony. Tobacco is unlikely to be an important source of environmental exposure to antimony during infancy and early childhood.     

Regional Variation in Wound Contraction of Mohs Surgery Defects Allowed to Heal by Second Intention

BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome.     

Innovative Laboratory Techniques to Facilitate Processing of Large Mohs Cases

Background Processing multiple tissue sections in large Mohs cases is time consuming and labor intensive.
Objective To present innovative laboratory techniques to facilitate processing of large Mohs cases.
Methods A method for processing a large dermatofibrosarcoma protuberans Mohs case is outlined.
Results Modifications in tissue processing and equipment employed in a large Mohs case are presented.
Conclusion Innovative modifications to the standard Mohs laboratory technique can facilitate processing of large Mohs cases, resulting in high-quality, rapid frozen sections while optimizing efficiency.     

激光生物效应及医学应用研究

激光作用于生物体会产生物理、化学或生物学的效应,激光正是通过这些效应达到医学基础研究、诊断和治疗疾病的目的.本文简介了激光与生物组织相互作用所产生的生物效应,概述了激光生物效应在生物学和医学研究中的应用.     

Reduced parenchymal cerebral blood flow is associated with greater progression of brain atrophy: The SMART-MR study

Global cerebral hypoperfusion may be involved in the aetiology of brain atrophy; however, long-term longitudinal studies on this relationship are lacking. We examined whether reduced cerebral blood flow was associated with greater progression of brain atrophy. Data of 1165 patients (61 ± 10 years) from the SMART-MR study, a prospective cohort study of patients with arterial disease, were used of whom 689 participated after 4 years and 297 again after 12 years. Attrition was substantial. Total brain volume and total cerebral blood flow were obtained from magnetic resonance imaging scans and expressed as brain parenchymal fraction (BPF) and parenchymal cerebral blood flow (pCBF). Mean decrease in BPF per year was 0.22% total intracranial volume (95% CI: –0.23 to –0.21). Mean decrease in pCBF per year was 0.24 ml/min per 100 ml brain volume (95% CI: –0.29 to –0.20). Using linear mixed models, lower pCBF at baseline was associated with a greater decrease in BPF over time (p = 0.01). Lower baseline BPF, however, was not associated with a greater decrease in pCBF (p = 0.43). These findings indicate that reduced cerebral blood flow is associated with greater progression of brain atrophy and provide further support for a role of cerebral blood flow in the process of neurodegeneration.     

红葡萄柚对冠状动脉粥样硬化患者血清甘油三酯水平的影响

研究了红葡萄柚和金黄色葡萄柚的生物活性化合物含量及其对高甘油三酯血症患者的影响。结果发现,与金黄色葡萄柚相比,红葡萄柚生物活性化合物含量和抗氧化能力均较高,该发现决定于氧自由基清除能力、1,1-二苯基-2-苦味基月井(1,1-diphenyl-2-picrylhydrazyl,DPH)、类胡萝卜素漂     

红细胞输注前的质量标准

现行红细胞输注规则主要规定红细胞采集量和输注时存活红细胞的比例,即450ml的采集量,输注时24h平均体内的存活率至少75%。其他还限制了游离血红蛋白的含量,通常不超过红细胞总量的1．0%。特殊需求的红细胞产品又有额外的要求。每单位少白细胞的红细胞的残余白细胞不超过1×10~6。