Nitrogen dioxide exposures inside ice skating rinks.

OBJECTIVES. The common operation of fuel-powered resurfacing equipment in enclosed ice skating rinks has the potential for producing high concentrations of carbon monoxide and nitrogen dioxide. Exposures to these gaseous combustion products may adversely affect the health of those inside the rink. Little information is available on pollutant concentrations under normal operating conditions. METHODS. One-week average nitrogen dioxide concentrations in 70 northeastern US rinks were measured with passive samplers during normal winter season conditions. RESULTS. The median nitrogen dioxide level inside rinks was 180 ppb, more than 10 times higher than the median outdoor concentration. One-week average nitrogen dioxide concentrations above 1000 ppb were measured in 10% of the rinks. CONCLUSIONS. Considering that short-term peak concentrations were likely to have reached two to five times the measured 1-week averages, our results suggest that nitrogen dioxide levels were well above short-term air quality guidelines and constitute a public health concern of considerable magnitude.     

硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用

研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。     

105Changes in Nitric Oxide Levels After Deep Dermal injury in the Female,Red Duroc Pig (FRDP)

Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model.     

Effects of gastrointestinal candidiasis, antibiotics, dietary arabinitol, and cortisone acetate on levels of the Candida metabolite D-arabinitol in rat serum and urine.

We studied the effects of gastrointestinal (GI) colonization by Candida albicans, dietary arabinitol, intragastric antibiotics, and cortisone on levels of the Candida metabolite D-arabinitol in rat serum and urine. Rats given conventional laboratory chow, intragastric gentamicin and chloramphenicol, and 6.0 x 10(8) live C. albicans B311 blastoconidia by gavage had minimal invasive GI disease and no more DL-arabinitol in the urine than controls given killed C. albicans. However, colonized and uncolonized rats given intragastric antibiotics had transiently higher urine arabinitol levels than the corresponding controls given saline. Rats given conventional laboratory chow (which contained 50 micrograms of arabinitol per g) had higher serum and urine arabinitol levels than rats given no dietary arabinitol, but the differences were less than expected. Moreover, intragastric antibiotics did not cause increased arabinitol excretion in rats given no dietary arabinitol. Rats given intragastric antibiotics and live C. albicans but no dietary arabinitol had no more arabinitol in their serum or urine than controls given antibiotics and killed C. albicans or saline and live or killed C. albicans. Lastly, cortisone acetate (10 mg/kg of body weight per day intramuscularly for 10 days) did not cause increased serum or urine arabinitol levels. We conclude that neither GI colonization by C. albicans nor cortisone should interfere with the usefulness of arabinitol as a marker for invasive candidiasis; antibiotics appear to increase arabinitol excretion by suppressing GI bacteria capable of consuming dietary arabinitol.     

The major dog allergens, Can f 1 and Can f 2, are salivary lipocalin proteins: cloning and immunological characterization of the recombinant forms.

Canis familiaris allergen 1 (Can f 1) and Canis familiaris allergen 2 (Can f 2) are the two major allergens present in dog dander extracts. We now report the isolation of cDNAs encoding both proteins and present their nucleotide and deduced amino acid sequences. Can f 1, produced by tongue epithelial tissue, has homology with the von Ebner's gland (VEG) protein, a salivary protein not previously thought to have allergenic properties. Can f 2, produced by tongue and parotid gland, has homology with mouse urinary protein (MUP), a known allergen. Both VEG protein and MUP are members of the lipocalin family of small ligand-binding proteins. Recombinant forms of Can f 1 and Can f 2 were produced and tested for immunoglobulin E (IgE) reactivity. Among dog-allergic subjects, 45% had IgE directed exclusively to rCan f 1, and 25% had IgE to both rCan f 1 and rCan f 2. In addition, both recombinant proteins were able to cross-link IgE and elicit histamine release from peripheral blood leucocytes in vitro. These findings confirm that Can f 1 and Can f 2 are major and minor dog allergens, respectively, and demonstrate that recombinant forms of dog allergens retain at least some IgE-binding epitopes.     

乳腺管状小叶癌

乳腺管状小叶癌（Tubulolobular carcinoma，TLC）最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征，并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁（中位年龄60岁）。1例双侧乳腺受累，5例病变为多灶性。肿瘤直径0．5-2．5cm，色灰褐，质硬。组织学观察：TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂，且两者比例相当（统称为管状小叶模式）。     

Isolation of Aeromonas hydrophila in diarrhea. Characterization of enterotoxinogenic strains and clinical relations

Aeromonas hydrophila is isolated from diarrhoea specimens with increasing frequency. The interest in this organism at the present time is related to the fact that it can produce a number of toxins, in particular alpha and beta cytotoxic haemolysins, an enterotoxin and various enzymes. The authors determined the frequency of isolation of this organism and tested the haemolytic, cytotoxic and enterotoxic effects of culture filtrates in all of the stool specimens received in their laboratory over a period of 9 months. At the same time, the clinical context was defined in order to demonstrate a relation between the aptitude of the strains to produce toxins and the presence of diarrhoea. The frequency of isolation of A. hydrophila was 0.88 per cent, which corresponds to 67 strains. 38 strains presented a haemolytic and/or enterotoxic activity, i.e. 57 per cent of the strains isolated. In diarrhoeal stools, 67 per cent of the A. hydrophila isolated produced at least one of the toxins, while in the group of patients without diarrhoea, only 38 per cent of the strains isolated produced toxins. The results obtained reveal a statistically significant correlation between the production of cytotoxic haemolysin and the presence of diarrhoea. In contrast, there was no correlation between the production of enterotoxin and the presence of diarrhoea. Twenty of the 67 strains ware isolated from children under the age of 2 years. In 40 per cent of cases, no other aetiology could be found for the diarrhoea, apart from the isolation of A. hydrophila.(ABSTRACT TRUNCATED AT 250 WORDS)