Particulate matter adheres to human hair exposed to severe aerial pollution: consequences for certain hair surface properties

BACKGROUND

The deposit and adherence of particulate matter (PM) from aerial pollution onto the surface of human hair is a poorly studied phenomenon.

OBJECTIVES

(i) To reproduce in vitro the deposit of known PM on standardized hair swatches in a closed box, (ii) to compare in vitro data with those obtained under 'real-life' conditions of severe aerial pollution and (iii) to assess the changes of the hair surface properties, potentially caused by the adherence of airborne PM onto the hair.

METHODS

In vitro: a PM was sprayed onto untreated or sebum-coated hair swatches. Real-life conditions: other swatches were exposed to a severely polluted environment, for 24 to 72 h, in Baoding (PR China). In both cases, swatches were examined using scanning electron microscopy. The shine, the frictional properties and the level of metals were measured and compared to those same properties for the unexposed swatches.

RESULTS

This work clearly indicates that, under real-life conditions, a large number of PM of various sizes are deposited onto the hair surface. This phenomenon is increased by the presence of sebum and longer exposure times. The in vitro level of PM deposited onto the hair surface is comparable to the in vivo level. The presence of sebum seems to favour the deposit of larger PM. The shine of the exposed swatches is significantly decreased, whereas their respective friction coefficients are significantly increased. Both the presence of sebum and length of exposure time increased the amount of analysed metals present on the exposed hair surface (Al, Fe, Cu, Ba and Zn).

CONCLUSION

This work indicates that a very high amount (e.g. billions) of PM can be deposited on a full head of hair for subjects living in a severely aerially polluted environment. This process can be reproduced in vitro. In real-life, pollution has a strong impact on hair surface properties, leading to a modification of the visual aspect (loss of shine) and the alteration of hair surface (increase in friction force). This work may be used to pave the way for prevention and cleansing studies in the field of hair care.

Fibroblast growth factor protects nitric oxide-induced apoptosis in neuronal SHSY-5Y cells

Fibroblast growth factor (FGF) has been shown to protect tissue damage in animal models of cerebral and myocardial ischemia. The cellular and molecular mechanisms of FGF effects have not been fully defined. In the present study, we have investigated the effect of FGF homologs on nitric oxide (NO)-mediated neuronal cell death. Addition of NO donor S-nitroso-N-acetylpenicillamine (SNAP) to cultures of human neuroblastoma SHSY-5Y cells resulted in a concentration-dependent cell death. TdT-mediated dUTP-X nick end labeling and oligonucleosome assays confirmed that NO-mediated cell death occurred through the apoptotic pathway. In the presence of 150 microM SNAP, about 40% of the cells in culture underwent apoptosis. Treatment with FGF-2 resulted in greater than 80% reduction in NO-induced cell death. FGF addition to cell cultures also enhanced cell survival without affecting cell proliferation. FGF-2 effectively inhibited NO-mediated apoptosis even when added 6 h after treatment with SNAP. Examination of other homologs of FGF on NO-mediated cell death showed that in SHSY-5Y cells, FGF-2 and FGF-4, but not other FGF homologs, inhibited NO-mediated apoptosis. These results show that FGF-2 was a potent cell survival factor and protected SHSY-5Y cells from NO-mediated apoptosis. These effects were limited to FGF-2 and FGF-4 homologs.

Brachial plexus nerve block with CT guidance for regional pain management: initial results

Brachial plexus nerve blocks are performed to treat patients with chronic pain referable to the brachial plexus. The needle insertion and trajectory are based on palpation of surface landmarks. Occasionally, the surface landmarks are difficult to identify owing to body habitus or anatomic alterations secondary to surgery or radiation therapy. The intent of this manuscript is to describe a technique for brachial plexus block guided with computed tomography and to report our initial results for regional pain management.

Acute epiglottitis despite vaccination with haemophilus influenzae type B vaccine

We present the case of a 20-month-old child who required admission to the intensive care with a presumptive diagnosis of acute laryngo-tracheo-bronchitis, for the management of acute upper airway obstruction. This child had received a complete course of Haemophilus influenzae type B (Hib) vaccine. Subsequent events showed that the diagnosis was not laryngo-tracheo-bronchitis but acute epiglottitis. We propose that a full course of vaccination is no guarantee against a subsequent illness with Hib and may actually lead to the wrong diagnosis and possibly life-threatening consequences.

Insulin regulation of glucose-6-phosphate dehydrogenase gene expression is rapamycin-sensitive and requires phosphatidylinositol 3-kinase

Glucose-6-phosphate dehydrogenase (G6PDH) controls the flow of carbon through the pentose phosphate pathway and also produces NADPH needed for maintenance of reduced glutathione and reductive biosynthesis. Hepatic expression of G6PDH is known to respond to several dietary and hormonal factors, but the mechanism behind regulation of this expression has not been characterized. We show that insulin similarly induces expression of endogenous hepatic G6PDH and a reporter construct containing 935 base pairs of the G6PDH promoter linked to luciferase in transient transfection assays. Using well tested and structurally distinct inhibitors of Ras farnesylation, lovastatin and B581, and a specific inhibitor of mitogen-activated protein kinase kinase activation, PD 98059, we show that the Ras/Raf/mitogen-activated protein kinase pathway is not utilized for the insulin-induced stimulation of G6PDH gene expression in primary rat hepatocytes. Similarly, using well characterized inhibitors of phosphatidylinositol 3-kinase, wortmannin and LY 294002, we show that PI 3-kinase activity is necessary for the induction of G6PDH expression by insulin. Rapamycin, an inhibitor of FRAP protein, which is involved in the activation of pp70 S6 kinase, blocks the insulin induction of G6PDH, suggesting that S6 kinase is also necessary for the insulin induction of G6PDH expression.

Social support and breast self-examination

Declining practice of breast self-examination (BSE) among women over the age of 55 years dramatically decreases the probability of early detection of breast cancer. About two-thirds of women who die of breast cancer are over the age of 55 years. Social support has been found to be associated with health behaviors. Although a woman's health may benefit from supportive relationships, the effect of diminished social networks on practices of BSE among older women has not been examined. Thus, the purpose of this study was to determine the relationship between social support and the frequency and accuracy of BSE practice. The sample consisted of 22 women, 55 years of age and older, who were having routine examinations at a small Midwestern gynecologic clinic. Social support was assessed by the Norbeck Social Support Questionnaire, and two tools assessed the accuracy and frequency of BSE. Social support was found to be significantly related to the frequency of BSE (r = 0.45, p < 0.05), but not to the accuracy of BSE (r = 0.28). The results also indicated that these women had lower social support scores compared with younger women. Planners of nursing intervention for BSE should consider health care providers as important resources in social support networks for the reinforcement of frequency and accuracy of BSE for older women.

Purification of the enhancing factor from mouse intestines

A unique polypeptide, called enhancing factor (EF), which enhances the binding of labeled epidermal growth factor (EGF) to cells, has been isolated. It has been purified to homogeneity from the acid-soluble proteins of mouse intestines. Earlier, EF was partially purified by two cycles of gel-permeation chromatography on Bio-Gel columns. We now report the final purification of EF on high-performance liquid chromatography (HPLC), using a reverse-phase column (mu Bondapak C18). The purity of the protein was confirmed when a single peak was obtained in HPLC. Also, a single protein band was obtained in SDS-PAGE. Purified EF has the same properties in vitro as those reported earlier for partially purified EF.

Production of vitamin B 12 analogues in patients with small-bowel bacterial overgrowth

We investigated the presence of vitamin B 12 analogues (cobamides) and the bacterial conversion of 57Co-B12 (vitamin B12 cyanocobalamin, [57Co]-CN-Cbl) into cobamides in the intestinal contents of four patients with bacterial overgrowth. The (57Co)-CN-Cbl bound to intrinsic factor was given orally. Jejunal contents were aspirated for 24 h and cultured aerobically and anaerobically. The CN-Cbl and cobamides were separated by electrophoresis and chromatography and identified by bioautography. Radioactivity of cobamide zones from duplicate chromatograms showed bacterial conversion of (57Co)-cn-cbl into cobamides. Cobamides ([Ade]CNCBA, [2-Me Ade] CNCba, [CN]2Cbi and factor E) were found in the intestinal contents in three of the four patients, and in two of three patients cobamides represented more than 25% of the administered CN-Cbl. Thus bacterial production of cobamides, both de novo and from ingested CN-Cbl bound to intrinsic factor, occurs in humans with bacterial overgrowth states and results in a significant loss of vitamin B12 to the host.