What theAspergillusgenomes have told us

The sequencing and annotation of the genomes of the first strains of Aspergillus nidulans, Aspergillus oryzae, and Aspergillus fumigatus will be seen in retrospect as a transformational event in Aspergillus biology. With this event the entire genetic composition of A. nidulans, the sexual experimental model organism of the genus Aspergillus, A. oryzae, the food biotechnology organism which is the product of centuries of cultivation, and A. fumigatus, the most common causative agent of invasive aspergillosis is now revealed to the extent that we are at present able to understand. Each genome exhibits a large set of genes common to the three as well as a much smaller set of genes unique to each. Moreover, these sequences serve as resources providing the major tool to expanding our understanding of the biology of each. Transcription profiling of A. fumigatus at high temperatures and comparative genomic hybridization between A. fumigatus and a closely related Aspergillus species provides microarray based examples of the beginning of functional analysis of the genomes of these organisms going forward from the genome sequence.

Apoptosis-stimulating protein of p53-2 (ASPP2/53BP2L) is an E2F target gene

The p53 pathway is a central apoptotic regulator. Deregulation of the Rb/E2F pathway occurs in a majority of tumors, resulting in both unrestrained proliferation and enhanced apoptosis sensitivity via p53-dependent and independent mechanisms. However, the mechanisms coupling the p53 and Rb/E2F pathways remain incompletely understood. We report that ASPP2/53BP2L, a p53/p73-binding protein that promotes p53/p73-dependent apoptosis, is an E2F target gene. The ASPP2/53BP2L promoter was identified and ectopic expression of transcription-competent E2F-1 (E2F-2 and E2F-3) stimulated an ASPP2/53BP2L promoter-luciferase reporter. Mutational analysis of the ASPP2/53BP2L promoter identified E2F-binding sites that cooperate for E2F-1 induction and basal repression of ASPP2/53BP2L. Moreover, endogenous ASPP2/53BP2L levels increased after E2F-1 expression, and E2F-1 bound the endogenous ASPP2/53BP2L promoter after chromatin immunoprecipitation. Typical for an E2F target, ASPP2/53BP2L expression was maximal in early S-phase. Thus, ASPP2/53BP2L is downstream of E2F, suggesting that it functions as a common link between the p53/p73 and Rb/E2F apoptotic pathways.

Effect of high-level natural radiation on chromosomes of residents in southern China

To study the effect of low-dose (rate) radiation on human health, we analyzed chromosomes of peripheral lymphocytes of residents in a high background radiation area (HBRA) and compared the results with those obtained from residents in a control area (CA) in Guangdong Province, China. Unstable types of chromosome aberrations (dicentrics and rings) were studied in 22 members of eight families in HBRA and 17 members of five families in CA. Each family consists of three generations. On average 2,600 cells per subject were analyzed. 27 adults and six children in HBRA and 25 adults and eight children in CA were studied with respect to translocations. On average 4,741 cells per subject were examined. We found an increase of the frequency of dicentrics and rings in HBRA, where the natural radiation level is three to five times higher than in the control area. But the increase of translocations in HBRA was within the range of individual variation in the controls.

A study of HLA-G1 protection of porcine endothelial cells against human NK cell cytotoxicity

Human natural killer (NK) cells, which can directly lyse porcine endothelial cells, play an important role in xenotransplantation. HLA-G is a nonclassical major histocompatibility complex (MHC) class I molecules that has been implicated in protecting susceptible target cells from lysis by NK cells. The objective was to study the effect of protecting porcine endothelial cells transfected with HLA-G1 from human NK cell lysis.

METHODS

The recombinant expression vector pcDNA3-HLA-G1 was transfected into primary cultured porcine aortic endothelial cells (PAECs) by lipofection. Surface expression of HLA-G1 in transected PAECs was confirmed by an immunofluoresence technique. Peripheral blood mononuclear cells (PBMC) and NK cell line (NK92) were used as NK effects cells with pcDNA3-HLA-G1-transfected PAECs as targets in a MTT method using pcDNA3 transfection as a negative control.

RESULTS

Expression of HLA-G1 on PAECs conferred significant protection against NK-mediated lysis. The rate of NK92 cytotoxicity was reduced to 41.5% +/- 14.0% from 75.3% +/- 10.5% in the control group (P < .01). Similarly the rate of the PBMC cytotoxicity among different donors (n = 7) was reduced to 45.4% +/- 12.1% in contrast to 74.6% +/- 11.2% in the control group (P < .05).

CONCLUSIONS

HLA-G1 molecules can directly protect xenogeneic PAECs against attack by human NK cells. These results indicate that the expression of HLA-G1 on the porcine cell surface may provide a new approach to overcome NK-mediated immunity to xenografts.

Pathogenesis and pathology of delayed xenograft rejection in pig-to-rhesus monkey cardiac transplantation

It has been recognized that delayed xenograft rejection (DXR) is the major barrier to the acceptance of xenotransplantation after overcoming hyperacute rejection.

OBJECTIVES

This study sought to investigate the pathogenesis and pathology of delayed xenograft rejection following pig-to-rhesus monkey heart xenotransplantation.

METHODS

Heterotopic xenogeneic heart transplants in the abdominal cavity were performed using piglet donors to four monkey recipients. Complete complement depletion was achieved in the recipients with repetitive doses of high-activity cobra venom factor (Y-CVF). The recipients were immunosuppressed with a combination of cyclosporine, cyclophosphamide, and steroids. Sera were analyzed for C3 and C4 levels and complement activity and anti-pig endothelial xenoantibody. The grafts were examined histopathologically and immunohistochemically for C3, C4;C5b-9, IgM, IgG, tumor necrosis factor-alpha (TNF-alpha), intercellular adhesion molecule-1(ICAM-1), CD57(NK cells), CD68 (macrophages), CD4, and CD8.

RESULTS

Xenografts survived 8, 10, 13, and 13 days respectively, all developing DXR. Venous thrombosis was the outstanding feature within DXR xenografts, complicated by interstitial edema, local hemorrhage, myocardial necrosis, and mild to moderate cellular infiltration. The serum C3 levels and complement activity decreased to almost 0 from the day of transplantation due to treatment with Y-CVF. The C4 level began to decrease 2 to 4 days before the cardiac xenografts lost their function. Anti-pig endothelial xenoantibody also decreased after transplantation, slightly increasing during DXR. All rejected xenografts showed C3, C4, C5b-9, IgG, and IgM deposits to various degrees. Large numbers of macrophages (50% of total leukocytes) infiltrated the entire xenograft with a few natural killer cells (8% to 10%), as well as some CD4+ T cells (15%) and CD8+ T cells (25%). Upregulation of ICAM-1 on graft endothelial cells and TNF-alpha in the interstitium were also demonstrated in the rejected heart.

CONCLUSION

Both humoral and cell-mediated immunologic reactions may play important roles in the pathogenesis of DXR. Besides C3, C4, C5b-9, IgM, and IgG destroying the xenograft, NK cells, macrophages, and CD4+ and CD8+ T cells may further aggravate the development of DXR.

Increased pulmonary arterial pressure in children with nephrotic syndrome

AIMS

To evaluate the pulmonary arterial pressure in children with nephrotic syndrome (NS).

METHODS

Doppler echocardiography was performed in 40 children with NS (aged 1.5-13 years) at NS onset (n = 28) or relapse (n = 12), and 40 normal controls. Pulmonary pressure was estimated by: (1) measuring the systolic transtricuspid gradient from tricuspid regurgitation; and (2) measuring the time to peak velocity of pulmonary flow.

RESULTS

Thirty five of the 40 patients with NS had measurable tricuspid regurgitation with a pulmonary systolic pressure ranging from 21 to 48 mm Hg. Pulmonary systolic pressure was >40 mm Hg in seven patients. The pulmonary time to peak velocity was shortened and the ratio of time to peak velocity and right ventricular ejection time decreased compared with controls. The patients with increased pulmonary pressure had a longer time since onset of NS. One patient developed thrombus in the inferior vena cava during hospitalisation.

CONCLUSION

Pulmonary arterial pressure was increased in children with NS. Further work is needed to evaluate the aetiology and clinical implications of this abnormality.

Global gene expression of fission yeast in response to cisplatin

The cellular response to the antitumor drug cisplatin is complex, and resistance is widespread. To gain insights into the global transcriptional response and mechanisms of resistance, we used microarrays to examine the fission yeast cell response to cisplatin. In two isogenic strains with differing drug sensitivity, cisplatin activated a stress response involving glutathione-S-transferase, heat shock, and recombinational repair genes. Genes required for proteasome-mediated protein degradation were up-regulated in the sensitive strain, whereas genes for DNA damage recognition/repair and for mitotic progression were induced in the resistant strain. The response to cisplatin overlaps in part with the responses to cadmium and the DNA-damaging agent methylmethane sulfonate. The different gene groups involved in the cellular response to cisplatin help the cells to tolerate and repair DNA damage and to overcome cell cycle blocks. These findings are discussed with respect to known cisplatin response pathways in human cells.

Does nitric oxide synthase contribute to the pathogenesis of Alzheimer's disease?: effects of beta-amyloid deposition on NOS in transgenic mouse brain with AD pathology

Oxidative stress is a risk factor for Alzheimer's disease (AD) whose major hallmark includes brain depositions of the amyloid beta peptide (Abeta) derived from the beta-amyloid precursor protein (APP). Our aim was to determine whether or not excessive Abeta deposition would alter nitric oxide synthase (NOS) activity, and thereby affect NOS-mediated superoxide formation. We compared NOS activity in brain extracts between Tg mice (expressing APP Swedish double mutation plus presenilin [PS-1] and nontransgenic [nTg] mice. Five brain regions, including cerebral cortex, hippocampus, cerebellum, and striatum from both nTg and Tg mice showed a detectable level of neuronal (n) NOS activity. Cerebellar extracts from both nTg and Tg mice displayed the highest level of nNOS activity, which was fourfold higher than cortical extracts. Although there was an increase in nNOS activity in Tg brain extracts, this did not attain statistical significance. A similar result was obtained for inducible NOS levels. Our results suggest that excess levels of Abeta failed to both trigger NOS activity and change NOS levels.

Rainbow: a toolbox for phylogenetic supertree construction and analysis

Rainbow is a program that provides a graphic user interface to construct supertrees using different methods. It also provides tools to analyze the quality of the supertrees produced. Rainbow is available for Mac OS X, Windows and Linux.

AVAILABILITY

Rainbow is a free open-source software. Its binary files, source code, and manual can be downloaded from the Rainbow web page: http://genome.cs.iastate.edu/Rainbow/

Interleukin-1 gene cluster polymorphisms and risk of Alzheimer?s disease in Chinese Han population

Interleukin-1 (IL-1) has been implicated as a key cytokine in Alzheimer's disease (AD) pathogenesis. IL-1 gene polymorphisms, especially IL-1A C((-)889)T polymorphism, have been suggested to be associated with AD risk and onset age. To determine if IL-1 polymorphisms are genetic risk factors for developing AD in Chinese Mainland population, we analyzed IL-1A ((-)889), IL-1B ((-)511) and IL-1RN variable number of tandem repeat (VNTR) polymorphisms in a sample of 145 sporadic AD patients and 181 healthy controls. Our data revealed that the three polymorphisms in IL-1 gene cluster might not play a key role in AD pathogenesis in Chinese Mainland Han population.

Histamine and histidine decarboxylase are hallmark features of ECL cells but not G cells in rat stomach

The oxyntic mucosa of the rat stomach is rich in ECL cells which produce and secrete histamine in response to gastrin. Histamine and the histamine-forming enzyme histidine decarboxylase (HDC) have been claimed to occur also in the gastrin-secreting G cells in the antrum. In the present study, we used a panel of five HDC antisera and one histamine antiserum to investigate whether histamine and HDC are exclusive to the ECL cells. By immunocytochemistry, we could show that the ECL cells were stained with the histamine antiserum and all five HDC antisera. The G cells, however, were not stained with the histamine antiserum, but with three of the five HDC antisera. Thus, histamine and HDC coexist in the ECL cells (oxyntic mucosa) but not in G cells (antral mucosa). Western blot analysis revealed a typical pattern of HDC-immunoreactive bands (74, 63 and 54 kDa) in oxyntic mucosa extracts with all five antisera. In antral extracts, immunoreactive bands were detected with three of the five HDC antisera (same as above); the pattern of immunoreactivity differed from that in oxyntic mucosa. Food intake of fasted rats or treatment with the proton pump inhibitor omeprazole raised the HDC activity and the HDC protein content of the oxyntic mucosa but not of the antral mucosa; the HDC activity in the antrum was barely detectable. We suggest that the HDC-like immunoreactivity in the antrum represents a cross-reaction with non-HDC proteins and conclude that histamine and HDC are hallmark features of ECL cells but not of G cells.

A comparative study of quantitative structure-activity relationship methods based on gallic acid derivatives

By using hologram quantitative structure-activity relationship (HQSAR) and comparative molecular field analysis (CoMFA) methods, the relationships between the structures of 49 gallic acid derivatives and their analgesic activity have been investigated to yield statistically reliable models with considerable predictive power. The best HQSAR model was generated using atoms, bond and connectivity as fragment distinction parameters and fragment size 5-7 from a hologram length of 307 with 3 components. High conventional r2 (r2 = 0.825) and cross-validation r2 (r2(cv) = 0.726) values were obtained. CoMFA analyses varying lattice size and location, grid spacing, probe charges and using, Tripos standard and Indicator force field were performed. The best model was developed with 4 components using sp3-hybridized carbon atom with +1.0 charge as probe, grid spacing (2 A), lattice offset (1.0, 3.0, -2.5). The CoMFA model showed a conventional correlation coefficient r2 of 0.889 and across-validation r2(cv) equals to 0.633. The robustness and predictive ability of the HQSAR and CoMFA models have been validated by means of an external test set. The results indicate that both models possess high statistical quality in the prediction of analgesic potency of novel gallic acid analogs.

Development of Co-Dominant Amplified Polymorphic Sequence Markers in Rice that Flank the Magnaporthe grisea Resistance Gene Pi7(t) in Recombinant Inbred Line 29

ABSTRACT Pi7(t), a dominant blast resistance gene derived from the rice cultivar Moroberekan, confers complete resistance against the fungal pathogen Magnaporthe grisea. Pi7(t) previously was positioned on chromosome 11 by restriction fragment length polymorphism (RFLP) mapping of a recombinant inbred line population. One derivative of this population, recombinant inbred line (RIL)29, was designated as the representative line for Pi7(t). A segregating F2 population was created from RIL29 in order to determine the location of Pi7(t). The new mapping data indicate a position for Pi7(t) 30 centimorgans distal to the original location. Pi7(t) shares a common position with the previously mapped Pi1 M. grisea resistance gene. RIL29 carries DNA not derived from either parent used to create the RIL population at the newly assigned Pi7(t) locus. RFLP analysis has identified a possible donor source.

Peptide deformylase inhibitors as antibacterial agents: identification of VRC3375, a proline-3-alkylsuccinyl hydroxamate derivative, by using an integrated combinatorial and medicinal chemistry approach

Peptide deformylase (PDF), a metallohydrolase essential for bacterial growth, is an attractive target for use in the discovery of novel antibiotics. Focused chelator-based chemical libraries were constructed and screened for inhibition of enzymatic activity, inhibition of Staphylococcus aureus growth, and cytotoxicity. Positive compounds were selected based on the results of all three assays. VRC3375 [N-hydroxy-3-R-butyl-3-(2-S-(tert-butoxycarbonyl)-pyrrolidin-1-ylcarbonyl)propionamide] was identified as having the most favorable properties through an integrated combinatorial and medicinal chemistry effort. This compound is a potent PDF inhibitor with a K(i) of 0.24 nM against the Escherichia coli Ni(2+) enzyme, possesses activity against gram-positive and gram-negative bacterial pathogens, and has a low cytotoxicity. Mechanistic experiments demonstrate that the compound inhibits bacterial growth through PDF inhibition. Pharmacokinetic studies of this drug in mice indicate that VRC3375 is orally bioavailable and rapidly distributed among various tissues. VRC3375 has in vivo activity against S. aureus in a murine septicemia model, with 50% effective doses of 32, 17, and 21 mg/kg of body weight after dosing by intravenous (i.v.), subcutaneous (s.c.), and oral (p.o.) administration, respectively. In murine single-dose toxicity studies, no adverse effects were observed after dosing with more than 400 mg of VRC3375 per kg by i.v., p.o., or s.c. administration. The in vivo efficacy and low toxicity of VRC3375 suggest the potential for developing this class of compounds to be used in future antibacterial drugs.

MEPE has the properties of an osteoblastic phosphatonin and minhibin

Matrix extracellular phosphoglycoprotein (MEPE) is expressed exclusively in osteoblasts, osteocytes and odontoblasts with markedly elevated expression found in X-linked hypophosphatemic rickets (Hyp) osteoblasts and in oncogenic hypophosphatemic osteomalacia (OHO) tumors. Because these syndromes are associated with abnormalities in mineralization and renal phosphate excretion, we examined the effects of insect-expressed full-length human-MEPE (Hu-MEPE) on serum and urinary phosphate in vivo, (33)PO(4) uptake in renal proximal tubule cultures and mineralization of osteoblast cultures. Dose-dependent hypophosphatemia and hyperphosphaturia occurred in mice following intraperitoneal (IP) administration of Hu-MEPE (up to 400 microg kg(-1) 31 h(-1)), similar to mice given the phosphaturic hormone PTH (80 microg kg(-1) 31 h(-1)). Also the fractional excretion of phosphate (FEP) was stimulated by MEPE [65.0% (P < 0.001)] and PTH groups [53.3% (P < 0.001)] relative to the vehicle group [28.7% (SEM 3.97)]. In addition, Hu-MEPE significantly inhibited (33)PO(4) uptake in primary human proximal tubule renal cells (RPTEC) and a human renal cell line (Hu-CL8) in vitro (V(max) 53.4% inhibition; K(m) 27.4 ng/ml, and V(max) 9.1% inhibition; K(m) 23.8 ng/ml, respectively). Moreover, Hu-MEPE dose dependently (50-800 ng/ml) inhibited BMP2-mediated mineralization of a murine osteoblast cell line (2T3) in vitro. Inhibition of mineralization was localized to a small (2 kDa) cathepsin B released carboxy-terminal MEPE peptide (protease-resistant) containing the acidic serine-aspartate-rich motif (ASARM peptide). We conclude that MEPE promotes renal phosphate excretion and modulates mineralization.

Unrecordable pulsatile ocular blood flow may signify severe stenosis of the ipsilateral internal carotid artery

AIM

To examine the relation between stenosis of the internal carotid artery (ICA) and pulsatile ocular blood flow (POBF).

METHODS

In 57 eyes of 30 patients who were referred for Doppler ultrasound examination of the ICA we measured POBF and analysed the correlation with degree of ipsilateral ICA stenosis.

RESULTS

There was a significant negative correlation between POBF and ipsilateral ICA stenosis (Pearson correlation coefficient, r=-0.516, p<0.0001). In 14 eyes POBF could not be measured by the OBF tonometer, and in 11 of these cases (79%) severe stenosis (>75%) of the ipsilateral ICA was present. When these eyes were excluded from analysis, there was no correlation between POBF and ICA stenosis (r=-0.02, p=0.91). Among these 43 eyes in which POBF could be measured it ranged 667-2095 microl/min with a mean of 970.72 microl/min.

CONCLUSION

Low or unrecordable POBF may signify severe stenosis of the internal carotid artery. POBF is not a direct reflection of ipsilateral ICA blood flow.

Radiation fields in gynecologic oncology: correlation of soft tissue (surgical) to radiologic landmarks

OBJECTIVES

(1). To determine if radiation fields defined by bony structure landmarks correlate to anatomic boundaries of lymph node dissection marked intraoperatively; and (2). to determine if a patient's body mass index (BMI) correlates with these anatomic or radiographic boundaries.

METHODS

One hundred patients undergoing exploratory laparotomy with pelvic and paraaortic lymph node dissection had three medium hemoclips placed at vascular junctions considered of clinical significance to lymph node dissection: insertion of the left ovarian vein into the renal vein, insertion of the right ovarian vein into the vena cava, inferior mesenteric artery (IMA), bifurcation of the aorta, bifurcation of the common iliacs (bilateral), and the insertion of the deep circumflex vein (DCV) in to the external iliac vein (bilateral). Postoperatively, an abdominal X-ray was obtained. Comparisons were made between these eight major vascular landmarks and radiographic bony landmarks that are used to define radiation field boundaries. The percentage of vascular landmarks that were encompassed or fell outside of traditional radiation fields was determined with a 1-cm margin considered an adequate boundary for radiation. These measurements were also compared to patient BMIs.

RESULTS

Radiation fields defined by traditional bony landmarks would adequately encompass the paraaortic lymph nodes in the majority of patients (91%). For pelvic radiation fields, there was a significant "miss" (39%) of common iliac lymph nodes. Approximately one quarter (26%) of patients would receive inadequate coverage of one or both of the lateral boundaries of pelvic radiation. There was no apparent correlation of BMI to vascular or bony landmarks.

CONCLUSIONS

Radiation fields determined by traditional bony landmarks do not adequately reflect the anatomic (surgical) landmarks associated with the lymphatic drainage of the female reproductive organs. Although the majority of tertiary care centers now use advanced imaging techniques (e.g. computed tomography) to plan their radiation treatments, the historical guidelines of radiographic landmarks are still used in smaller institutions and continue to be referenced in Gynecologic Oncology Group protocols. For centers still using radiographic landmarks, the application of hemoclips with X-ray identification is a low-cost modality that is easily reproducible and may be clinically useful in guiding treatment.

α-Substituted hydroxamic acids as novel bacterial deformylase inhibitor-based antibacterial agents

We report the synthesis and biological activity of analogues of VRC3375 (N-hydroxy-3-R-butyl-3-[(2-S-(tert-butoxycarbonyl)-pyrrolidin-1-ylcarbonyl]propionamide), an orally active peptide deformylase inhibitor. This study explores the structure-activity relationship of various chelator groups, alpha substituents, P(2)' and P(3)' substituents in order to achieve optimal antibacterial activity with minimal toxicity liability.

[Prognosis of severe trauma outcome using noninvasive monitoring]

The purpose of the case study was, firstly, to evaluate (starting from the time the patients are admitted to the intensive care unit--ICU) a type of cardiac, pulmonary and peripheral microcirculation in patients with severe traumas by using a multi-component and invasion-free monitoring; the second purpose was to measure quantitatively the changes in the cardiac, pulmonary and peripheral hemodynamics leading to recovery or death; and finally, it was to investigate the effectiveness of applying the discriminative analysis for the sake of assessing the biological value of the controllable changes and of forecast outcome. The invasion-free monitoring system comprising the below tools was in use: an improved bio-impedance method (evaluation of the cardiac output), pulsometry (examination of the pulmonary function), transcutaneous oxygen pressure (tissue perfusion function) and arterial blood pressure (ABP--general circulation status). The results of continuously controllable invasion-free measurements were used for a prospective evaluation at the emergency unit of the county hospital, which was supervised by the university. The accumulated integral values of the deficit or excess of each controllable parameter were calculated by using the differences between the normal values and the values obtained for each patient and for the groups of survivors and dead. A probable outcome and a degree of the deficit of the pulmonary and cardiac functions as well as of the tissue-perfusion function were analyzed by using the discriminant function. The values of pure aggregate deficits (-) or excesses (+) were for the survivors and dead, respectively, as follows: cardiac index--(+)93 +/- 49.8 l/m2 versus -232 +/- 138 l/m2 (p < 0.07); mean ABD(-)-12 +/- 12.4 mm Hg versus -57 +/- 23.5 mm Hg (p < 0.066); arterial saturation(-)-1 +/- 0.09% h versus -9 +/- 2.6% h (p < 0.001): and tissue perfusion--(+)311 +/- 87 tor/h versus 793 +/- 175 tor/h (p < 0.0001). The pure aggregate value of reduced circulation, tissue perfusion and of hypoxemia degree was found to be higher in the dead versus the survivors. The invasion-free monitoring systems secure a constant real-time control over the data, which makes the circulatory malfunction revealed as soon as possible in emergency settings. The mentioned systems can be used to describe, for each patients, a temporal hemodynamic model and to evaluate quantitatively a functional-deficit severity; they also provide for composing a clear-cut and successive treatment scheme from the emergency stage to the intensive care unit.