First-time donors responding to a national disaster may be an untapped resource for the blood centre

BACKGROUND

On 12 May 2008, a severe earthquake struck Sichuan in China. Many people donated blood for the first time, leading us to question whether these donors might become repeat donors in the future. The return pattern of post-earthquake first-time donors (PEFTD) was compared with that of first-time donors (FTD) in a comparable period.

METHODS

Demographic characteristics, transfusion-transmissible infection rates and 1-year return rates were compared between 5147 PEFTD (5/13-5/19, 2008) and 3176 FTD (5/13-5/19, 2009) from five Chinese blood centres using chi-squared tests. Adjusted logistic regression was used to detect earthquake effect on donor return.

RESULTS

Post-earthquake first-time donors were more frequently between 26 and 45 years, men, and better educated compared with the control group. Slightly higher but not statistically significant increased rates of hepatitis B virus surface antigen (HBsAg) (0·87% vs. 0·50%, P=0·054), hepatitis C virus (HCV) (0·70% vs. 0·63%, P=0·414), syphilis (0·9% vs. 0·7%, P=0·489) and lower rates of human immunodeficiency virus (HIV) (0·31% vs. 0·60%, P=0·078) reactivity were detected for PEFTD. The 1-year return rate for PEFTD was significantly lower than that of the controls (8·0% vs. 13·0%, P<0·001). After adjusting for demographic factors, donation volume and sites, the PEFTD were less likely to return in 1 year than the controls (OR: 0·520; 95% CI: 0·442, 0·611).

CONCLUSION

Post-earthquake first-time donors may be less likely to donate again without continuing motivation strategies. Further studies on PEFTD's lack of motivation to return for donation are needed to design recruitment strategies to convert PEFTD to become repeat donors to continuously replenish the blood supply.

Calpain-mediated regulation of stargazin in adult rat brain

Changes in AMPA receptors have been proposed to underlie changes in synaptic efficacy in hippocampus and other brain structures. Calpain activation has also been discussed as a potential mechanism to produce lasting modifications of synaptic structure and function. Stargazin is a member of the family of transmembrane AMPA receptor associated proteins (TARPs), which participates in trafficking of AMPA receptors and regulates their kinetic properties. We report here that preincubation of thin (20 μm) frozen rat brain sections with calcium changes the immunological properties of stargazin, an effect totally blocked by a calpain inhibitor. Immunocytochemistry indicates that in situ calpain activation produces a decreased immunoreactivity for stargazin in the neuropil throughout the brain, and Western blots confirmed that a similar treatment decreased stargazin levels. Interestingly, the same treatment did not modify the immunoreactivity for another TARP member, γ-8, although it increased immunoreactivity in cell bodies in hippocampus, an effect that was not blocked by calpain inhibition. These results strongly suggest the involvement of calpain in the regulation of AMPA receptor targeting and function through truncation of stargazin.

Simple and inexpensive method of wood pellets macro-porosity measurement

A novel simplified stereometric measurement method for determining the macro-porosity of wood pellets through geometrical approach was successfully developed and tested. The irregular ends of pellets of circular cross-section were sanded flat so that their geometry becomes cylinder and their volumes evaluated using mensuration formula. Such formed cylindrical pellets were loose or tap filled to selected volumes to evaluate the macro-porosity and the constant specific weight. The method was extended to evaluate actual wood pellets properties. Overall macro-porosity of actual wood pellets was determined as 41.0+/-2.5% and 35.5+/-2.7%, mean bulk density as 670+/-29 kg m(-3) and 731+/-31 kg m(-3), and classified as "Class-3:Medium" and "Class-3&4:Medium to Low" for loose and tapped fills, respectively. Hausner ratio and Carr's compressibility index classify wood pellets as "freely flowing." The developed stereometric method can be used as a handy inexpensive laboratory procedure to estimate the macro-porosity of different types and makes of wood pellets and other similar packaged materials.

Permeability of wood pellets in the presence of fines

Broken pellets and fines are produced when pellets are handled. The resistance to air flow was measured for clean pellets and for pellets mixed with 1-20% broken pellets (fines). A pellet diameter was 6mm. The lengths ranged from 6 to 12 mm. Clean pellets were defined as particles that remained on a 4mm screen. A typical sieve analysis showed 30% of the mass of particles that passed through the 4mm screen was smaller than 1mm. The airflow rates used in the experiment ranged from 0.004 to 0.357 ms(-1). The corresponding pressure drop ranged from 1.9 to 271 Pam(-1) for clean pellets, from 4.8 to 1100 Pam(-1) for 10% fines content, and from 7.9 to 1800 Pam(-1) for 20% fines content. Coefficients of Hukill and Ives' equation were estimated for clean pellets and a multiplier was defined to calculate pressure drop for pellets mixed with fines.

Identification of Interferon Regulatory Factor (IRF)-5 Tumor Suppressor Function in Human Breast Cancer

Background: Transcription factors of the IRF family participate in the early host response to pathogens, hematopoietic differentiation and immunomodulation. IRFs can regulate cell growth and apoptosis thereby affecting the susceptibility to and progression of cancer. IRF-1 was recently identified as a tumor suppressor in breast cancer. Early evidence from our lab and others suggests that IRF-5 may also have tumor suppressor activities. Although loss of IRF-5 expression has recently been shown to enhance transformation by Ha-ras, very little is known of IRF-5 tumor suppressor function(s).Material and Methods: Using paraffin-embedded formalin-fixed human breast tissue specimens from 64 patients with varying stages of ductal carcinoma, we analyzed and compared the expression of IRF-1 and IRF-5 by immunofluorescence (IF). Clinical data, such as histological subtype, stage, and receptor expression (ER, PR Her-2) were available for clinicopathological correlations. Protein levels were also determined in normal human breast epithelial MCF-10A, and -12A cells, and in cancer cell lines MCF-7, MDA-MB-231, -468, and T47D by immunoblot and IF. By retroviral infection, we overexpressed IRF-5 in breast cancer cell lines or knocked-down IRF-5 in normal MCF-10A and -12A cells and examined cell growth, apoptosis, metastasis and sensitivity to cytotoxic stress. In vivo tumor suppressor function was determined in NCr nu/nu mice inoculated with MCF-7 or MDA-MB-231 cells expressing or lacking IRF-5.Results: We confirmed recent data on IRF-1 revealing that it is expressed less frequently in tumor tissue of high-grade ductal carcinoma in situ (DCIS) or invasive DC compared with normal breast tissue. Data from patient samples indicate a significant difference between IRF-1 and IRF-5 expression that was distinctly associated with breast cancer disease stages, including early-to-late stage DCIS, suggesting their utilization as prognostic indicators.Similar findings were made in breast cancer cell lines. We demonstrate that forced expression of IRF-5 in breast cancer cells inhibits colony formation, sensitizes cells to cytotoxic stress-induced apoptosis, inhibits metastasis, and tumor formation in nude mice. Conversely, knockdown of IRF-5 in MCF-10A and -12A cells resulted in resistance to stress-induced cell death.Discussion: Data from this study strongly support a tumor suppressor function for IRF-5 in breast cancer. Ultimately, the study is expected to lead us to the identification of new prognostic indicators and therapeutic approaches for the treatment of breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3160.

Different pathways are involved in arsenic-trioxide-induced cell proliferation and growth inhibition in human keratinocytes

BACKGROUND

Arsenic is a carcinogen that is associated with an increased risk of human skin cancer. On the other hand, arsenic trioxide (As(2)O(3)) has potential anticancer activity against a wide range of carcinomas. The mechanisms involved in these two opposing processes remain unclear.

METHODS

We used normal human keratinocytes (NHK), the human keratinocyte HaCaT cell line and human epidermal carcinoma cells (A431 cell line) to investigate potential pathways involved in the effects on cell proliferation and growth inhibition by different concentrations of As(2)O(3).

RESULTS

At low concentrations (0.5-32 nM), As(2)O(3) enhanced keratinocyte proliferation and regulated the expression of about 172 genes. Among them, cell cycling pathway genes (including CDK4 and E2F1) were significantly upregulated. At high concentrations (0.5-10 microM), As(2)O(3) inhibited cell growth in NHK and HaCaT cells, but not in A431 cells. As(2)O(3) significantly induced NHK and HaCaT apoptosis through the activation of caspase-3, as well as cell cycle arrest at the G2-M phase.

CONCLUSION

Our data suggest that different pathways are involved in As(2)O(3)-mediated proliferation and growth inhibition. In addition, skin carcinoma cells were resistant to As(2)O(3)-induced cell growth inhibition and apoptosis when compared to NHK and HaCaT cells. Therefore, As(2)O(3) may not be appropriate for treatment of skin carcinomas.

Polyamine-based analogues as biochemical probes and potential therapeutics

The polyamines putrescine, spermidine and spermine are ubiquitous polycationic compounds that are found in nearly every cell type, and are required to support a wide variety of cellular functions. The existence of multiple cellular effector sites for naturally occurring polyamines implies that there are numerous targets for polyamine-based therapeutic agents. Through a programme aimed at the synthesis and evaluation of biologically active polyamine analogues, our laboratory has identified three distinct structural classes of polyamine derivatives that exhibit promising biological activity in vitro. We have synthesized more than 200 symmetrically and unsymmetrically substituted alkylpolyamines that possess potent antitumour or antiparasitic activity, depending on their backbone architecture and terminal alkyl substituents. Along similar lines, we have developed novel polyamino(bis)guanidines and polyaminobiguanides that are promising antitrypanosomal agents and that interfere with biofilm formation in the pathogenic bacterium Yersinia pestis. Finally, we recently reported a series of PAHAs (polyaminohydroxamic acids) and PABAs (polyaminobenzamides) that inhibit HDACs (histone deacetylases), and in some cases are selective for individual HDAC isoforms. These studies support the hypothesis that polyamine-based small molecules can be developed for use as biochemical probes and as potential therapies for multiple diseases.

The use of Medpor coated tear drainage tube in conjunctivodacryocystorhinostomy

PURPOSE

To analyse outcomes of lacrimal bypass surgery with the Medpor coated tear drainage tube.

METHODS

A total of 26 eyes in 26 patients with persistent epiphora who failed canaliculoanastomosis and dacryocystorhinostomy were treated by the lacrimal bypass surgery with the Medpor coated tear drainage tubes. Ten cases of severe obstruction of punctum and canaliculi and 16 cases with both upper system and lacrimal sac obstruction comprised this cohort of patients.

RESULTS

No tube extrusion or displacement was observed after 6-28 months of follow-up. Complete or significant resolution of epiphora was achieved in 23/26 cases (88.5%). Luminal obstruction by debris was noted in nine eyes, ocular discomfort in four, improper tube size selection in two, malposition in one, infection in one, diplopia in one, corneal abrasion in one, and reflux of intranasal secretion into fornix in another.

CONCLUSION

Medpor coated tear drainage tube offers tube stabilization in minimizing tube extrusion and displacement.

A novel method for determination of collagen orientation in cartilage by Fourier transform infrared imaging spectroscopy (FT-IRIS)

OBJECTIVE

The orientation of collagen molecules is an important determinant of their functionality in connective tissues. The objective of the current study is to establish a method to determine the alignment of collagen molecules in histological sections of cartilage by polarized Fourier transform infrared imaging spectroscopy (FT-IRIS), a method based on molecular vibrations.

METHODS

Polarized FT-IRIS data obtained from highly oriented tendon collagen were utilized to calibrate the derived spectral parameters. The ratio of the integrated areas of the collagen amide I/II absorbances was used as an indicator of collagen orientation. These data were then applied to FT-IRIS analysis of the orientation of collagen molecules in equine articular cartilage, in equine repair cartilage after microfracture treatment, and in human osteoarthritic cartilage. Polarized light microscopy (PLM), the most frequently utilized technique to evaluate collagen fibril orientation in histological sections, was performed on picrosirius red-stained sections for comparison.

RESULTS AND CONCLUSION

Thicknesses of each zone of normal equine cartilage (calculated based on differences in collagen orientation) were equivalent as determined by PLM and FT-IRIS. Comparable outcomes were obtained from the PLM and FT-IRIS analyses of repair and osteoarthritis tissues, whereby similar zonal variations in collagen orientation were apparent for the two methods. However, the PLM images of human osteoarthritic cartilage showed less obvious zonal discrimination and orientation compared to the FT-IRIS images, possibly attributable to the FT-IRIS method detecting molecular orientation changes prior to their manifestation at the microscopic level.

Uptake and pathogenic effects of amyloid beta peptide 1-42 are enhanced by integrin antagonists and blocked by NMDA receptor antagonists

Many synapses contain two types of receptors - integrins and N-methyl-D-aspartate (NMDA) receptors - that have been implicated in peptide internalization. The present studies tested if either class is involved in the uptake of the 42-residue form of amyloid beta peptide (Abeta1-42), an event hypothesized to be of importance in the development of Alzheimer's disease. Cultured hippocampal slices were exposed to Abeta1-42 for 6 days in the presence or absence of soluble Gly-Arg-Gly-Asp-Ser-Pro, a peptide antagonist of Arg-Gly-Asp (RGD)-binding integrins, or the disintegrin echistatin. Abeta uptake, as assessed with immunocytochemistry, occurred in 42% of the slices incubated with Abeta peptide alone but in more than 80% of the slices co-treated with integrin antagonists. Uptake was also found in a broader range of hippocampal subfields in RGD-treated slices. Increased sequestration was accompanied by two characteristics of early stage Alzheimer's disease: elevated concentrations of cathepsin D immunoreactivity and activation of microglia. The selective NMDA receptor antagonist D-(-)-2-amino-5-phosphonovalerate completely blocked internalization of Abeta, up-regulation of cathepsin D, and activation of microglia. Our results identify two classes of receptors that cooperatively regulate the internalization of Abeta1-42 and support the hypothesis that characteristic pathologies of Alzheimer's disease occur once critical intraneuronal Abeta concentrations are reached.

Evidence that integrins contribute to multiple stages in the consolidation of long term potentiation in rat hippocampus

Three structurally distinct groups of antagonists were used to test the hypothesis that integrin adhesion receptors play an essential role in consolidating (stabilizing) long term potentiation of the Schaffer collaterals in rat hippocampus. Comparisons were made of percent potentiation at antagonist-treated versus control sites within CA1 stratum radiatum of the same hippocampal slice. Function blocking antibodies against the alpha5 subunit of the fibronectin receptor had no effect on baseline responses or initial potentiation but resulted in a >30% reduction, relative to within-slice control long term potentiation, 45 min later. Larger reductions were recorded in separate experiments continued for 4 h after the induction of potentiation. Alpha(v) and alpha2 subunit antibodies did not reliably affect the stabilization of potentiation. An antagonist peptide with preference for beta1 integrins produced a slowly developing decline of the type seen with alpha5 antibodies. A cyclic peptide antagonist reduced potentiation within 10 min of induction and caused an almost 40% decrease over 45 min. Two disintegrins (snake toxins that potently block integrins) were very effective in preventing the consolidation of long term potentiation: echistatin reduced potentiation by >70%, while triflavin caused approximately 50% decrease. The suppressing effects of echistatin were concentration-dependent, obtained with treatment after induction, and much more rapid than the effects of antibodies. Rapid declines in potentiation were particularly evident when the two disintegrins were applied together. These results indicate that hippocampal fibronectin receptors (alpha5/beta1 integrin) contribute importantly to a slowly developing phase of long term potentiation consolidation. They also suggest that other integrins are critical to aspects of consolidation occurring in the first few minutes after induction.

Thermal stability and DPPC/Ca2+ interactions of pulmonary surfactant SP-A from bulk-phase and monolayer IR spectroscopy

Surfactant protein A (SP-A), the most abundant pulmonary surfactant protein, is implicated in multiple biological functions including surfactant homeostasis, biophysical activity, and host defense. SP-A forms ternary complexes with lipids and Ca2+ which are important for protein function. The current study uses infrared (IR) transmission spectroscopy to investigate the bulk-phase interaction between SP-A, 1,2-dipalmitoylphosphatidylcholine (DPPC), and Ca2+ ions along with IR reflection-absorption spectroscopy (IRRAS) to examine protein secondary structure and lipid orientational order in monolayer films in situ at the air/water interface. The amide I contour of SP-A reveals two features at 1653 and 1636 cm(-1) arising from the collagen-like domain and a broad feature at 1645 cm(-1) suggested to arise from the carbohydrate recognition domain (CRD). SP-A secondary structure is unchanged in lipid monolayers. Thermal denaturation of SP-A in the presence of either DPPC or Ca2+ ion reveals a sequence of events involving the initial melting of the collagen-like region, followed by formation of intermolecular extended forms. Interestingly, these spectral changes were inhibited in the ternary system, showing that the combined presence of both DPPC and Ca2+ confers a remarkable thermal stability upon SP-A. The ternary interaction was revealed by the enhanced intensity of the asymmetric carboxylate stretching vibration. The IRRAS measurements indicated that incorporation of SP-A into preformed DPPC monolayers at a surface pressure of 10 mN/m induced a decrease in the average acyl chain tilt angle from 35 degrees to 28 degrees. In contrast, little change in chain tilt was observed at surface pressures of 25 or 40 mN/m. These results are consistent with and extend the fluorescence microscopy studies of Keough and co-workers [Ruano, M. L. F., et al. (1998) Biophys. J. 74, 1101-1109] in which SP-A was suggested to accumulate at the liquid-expanded/liquid-condensed boundary. Overall these experiments reveal the remarkable stability of SP-A in diverse, biologically relevant environments.

[Studies on separation, purification and chemical structure of polysaccharide from Atractylodes macrocephala]

Separation and purification were done by column chromatographic fractionation; HPLC and 13C-NMR were used to determine the chemical structure of polysaccharide from Atractylodes macrocephala Koidz;, The molecular weight of the polysaccharide was estimated to be 1.36 x 10(5) (PSAM-1) and 1.04 x 10(5) (PSAM-2).