bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of hepatitis C virus with peg‐interferon and ribavirin combination therapy significantly affects lipid metabolism
Authors: Tada Shinichiro , Saito Hidetsugu , Ebinuma Hirotoshi , Ojiro Keisuke , Yamagishi Yoshiyuki , Kumagai Naoki , Inagaki Yasutaka , Masuda Tetsuya , Nishida Jiro , Takahashi Masahiko , Nagata Hiroshi , Hibi Toshifumi
Published: November 2008

Aim:  We investigated lipid metabolism in patients with chronic hepatitis C virus (HCV), serotype 1, undergoing combination therapy with PEG‐IFN α‐2b (PEG‐IFN) and ribavirin (RBV).

Methods:  A total of 185 patients with chronic HCV (HCV serotype 1; HCV RNA levels ≥ 100 KIU/mL) who received a combination of PEG‐IFN and RBV were enrolled.

Results:  Sustained virological response (SVR) was obtained in 82 cases (44.3%). The median age, red blood cell and platelet counts differed significantly between the SVR and non‐SVR groups before treatment. However there was no significant difference between total cholesterol (TC), LDL‐cholesterol (LDL‐C) and triglyceride (TG) levels before treatment. TC and LDL‐C levels decreased during the treatment in both groups. In the SVR group, TC and LDL‐C levels increased quickly after the end of the treatment and were higher than those before treatment. On the other hand, TC and LDL‐C levels returned to pretreatment levels in the non‐SVR group and were significantly lower than in the SVR group. TG levels were elevated in both groups after the beginning of treatment. After the end of treatment, this elevation persisted in the SVR group, while TG levels returned to pre‐treatment levels in the non‐SVR group. There was a significant difference in TG levels at 24 weeks after the end of the treatment between the 2 groups. In the non‐SVR group some patients achieved normalization of ALT (alanine aminotransferase) but persistence of normal ALT levels did not contribute to the increase of TC and TG.

Conclusion:  TC, LDL‐C and TG levels increase only in patients with HCV, serotype 1, undergoing combination therapy when a SVR is achieved.
Combination therapy of radiofrequency ablation and transarterial chemoembolization in recurrent hepatocellular carcinoma after hepatectomy compared with single treatment
Authors: Yang Wei , Chen Min Hua , Wang Mao Qiang , Cui Ming , Gao Wen , Wu Wei , Wu Jin Yu , Dai Ying , Yan Kun
Published: November 2008

Aim:  To assess the efficacy and safety of radiofrequency ablation (RFA) combined with transarterial chemoembolization (TACE) in recurrent hepatocellular carcinoma (HCC) after hepatectomy and to compare its outcome with a single modality.

Method:  We retrospectively studied 103 patients with recurrent HCCs after hepatectomy who were excluded from repeat hepatectomy. Of them, 81 patients were male and 22 were female (mean age 55.8 ± 10.7 years; range, 30–80 years). According to treatment modality, these patients were divided into three groups: RFA was used as the sole first‐line anticancer treatment in 37 patients (RFA group); TACE was used as the sole first‐line anticancer treatment in 35 patients (TACE group). RFA followed by TACE was performed in 31 patients (combination group). There was no significant difference in clinical material between the three groups. Indices including treatment success rate, intrahepatic recurrence rate and survival were obtained for analysis and comparison.

Results:  The treatment success rate of the combination group was significantly higher than that of the TACE group (93.5 vs. 68.6%, P = 0.011). The intrahepatic recurrence rate of the combination group was significantly lower than that of the TACE group (20.7 vs 57.1%, P = 0.002) and the RFA group (20.7 vs 43.2%, P = 0.036). The overall 1‐, 3‐ and 5‐year survival rates were 73.9, 51.1 and 28.0% respectively in the RFA group; 65.8, 38.9 and 19.5% respectively in the TACE group; and 88.5, 64.6 and 44.3% respectively in the combination group. There was a significant difference in survival between the combination group and the TACE group (P = 0.028).

Conclusion:  RFA combined with TACE was more effective in treating recurrent HCC after hepatectomy compared to single RFA or TACE treatment. This combination therapy can thus be a valuable choice of treatment for recurrent HCC.
Microsatellite instability in hepatocellular carcinoma in non‐cirrhotic liver in patients older than 60 years
Authors: Togni Roberto , Bagla Nipin , Muiesan Paolo , Miquel Rosa , O'Grady John , Heaton Nigel , Knisely Alex S , Portmann Bernard , Quaglia Alberto
Published: November 2008

Aim:  Hepatocellular carcinoma (HCC) in otherwise normal liver is rare, its pathogenesis remains obscure and the literature on the subject is scarce. We investigated microsatellite instability (MSI) in eight elderly patients (median age 70.7, range 63–76 years) without a clinical history of liver disease and who underwent liver resection for HCC in otherwise normal background liver between 2001 and 2005 at King's College Hospital, London.

Methods:  Immunohistochemistry for mutL homolog 1 (MLH1), mutS homolog 2 (MSH2), mutS homolog 6 (MSH6) and post‐meiotic segregation increased 2 (PMS2) was carried out on formalin‐fixed and paraffin‐embedded sections of tumor and background liver. MSI analysis was performed using a panel of monomorphic microsatellites markers: BAT‐25, BAT‐26, NR21, NR24 and NR27 and pentaplex PCR.

Results:  All HCC were solitary large tumors. Two also had satellite nodules. The background liver was usually unremarkable. There was nuclear expression of MLH1, MSH2, MSH6 and PMS2 in all tumors excluding a DNA mismatch repair defect. The same pattern of staining was noted in the hepatocytes of the background liver of all cases. No differences between microsatellite lengths in the background liver and in the tumor, as assessed in PCR products, were found for any of the five microsatellite markers in any patients. These findings provided no evidence for MSI.

Conclusion:  Our study showed that MSI is not implicated in the pathogenesis of a subset of HCC affecting elderly patients without chronic liver disease. Further studies are needed to clarify the pathogenesis of HCC in this particular setting.
Impact of determination of hepatitis B virus subgenotype and pre‐core/core‐promoter mutation for the prediction of acute exacerbation of asymptomatic carriers
Authors: Ikegami Tadashi , Matsuki Yasuhiko , Tanaka Yasuhito , Mizokami Masashi , Honda Akira , Hirayama Takeshi , Saito Yoshifumi , Matsuzaki Yasushi
Published: November 2008

Aim:  A large cohort study in Japan revealed that the specific viral profile may influence the fulminant outcome in acute hepatitis B virus (HBV) infections, while the genetic influence on outcome has not been clarified in patients with acute exacerbation of chronic liver disease caused by HBV. We experienced a case of fatal liver failure that developed as the result of chronic HBV infection. To determine possible genetic factor involving acute exacerbation, genetic analysis of serum from the patient and his siblings was performed.

Methods:  HBV subgenotype as well as pre‐core/core‐promoter mutations of samples mentioned above were determined.

Results:  Patient had HBV‐Bj with pre‐core (1896/1899) and core‐promoter (1762/1764) mutations, the genomic profile frequently seen in fulminant hepatitis caused by acute HBV infection.

Conclusion:  This result suggests that determination of the HBV subgenotype and pre‐core/core promoter mutations could provide a rationale for development of a treatment strategy in asymptomatic HBV carriers.
Spectroscopic Tracking of Structural Evolution in Ultrafast Stilbene Photoisomerization
Authors: Takeuchi Satoshi , Ruhman Sanford , Tsuneda Takao , Chiba Mahito , Taketsugu Tetsuya , Tahara Tahei
Published: November 2008

Understanding a chemical reaction ultimately requires the knowledge of how each atom in the reactants moves during product formation. Such knowledge is seldom complete and is often limited to an oversimplified reaction coordinate that neglects global motions across the molecular framework. To overcome this limit, we recorded transient impulsive Raman spectra during ultrafast photoisomerization of
cis
-stilbene in solution. The results demonstrate a gradual frequency shift of a low-frequency spectator vibration, reflecting changes in the restoring force along this coordinate throughout the isomerization. A high-level quantum-chemical calculation reproduces this feature and associates it with a continuous structural change leading to the twisted configuration. This combined spectroscopic and computational approach should be amenable to detailed reaction visualization in other photoisomerizing systems as well.
Response to Comment on "Ancient Asteroids Enriched in Refractory Inclusions"
Authors: Sunshine J. M. , Connolly H. C. , McCoy T. J. , Bus S. J. , La Croix L. M.
Published: November 2008

Although the exact abundance of phases in carbonaceous chondrites remains debatable, a potentially lower absolute abundance of calcium- and aluminum-rich inclusions (CAIs) in the Allende meteorite does not change our fundamental conclusion. In a relative comparison, CAI-rich asteroids contain two to three times as many CAIs as the most CAI-rich meteorites. These asteroids are therefore greatly enriched in the earliest solar system materials and remain enticing targets for future exploration.
Globally Distributed Uncultivated Oceanic N
2
-Fixing Cyanobacteria Lack Oxygenic Photosystem II
Authors: Zehr Jonathan P. , Bench Shellie R. , Carter Brandon J. , Hewson Ian , Niazi Faheem , Shi Tuo , Tripp H. James , Affourtit Jason P.
Published: November 2008

Biological nitrogen (N
2
) fixation is important in controlling biological productivity and carbon flux in the oceans. Unicellular N
2
-fixing cyanobacteria have only recently been discovered and are widely distributed in tropical and subtropical seas. Metagenomic analysis of flow cytometry–sorted cells shows that unicellular N
2
-fixing cyanobacteria in “group A” (UCYN-A) lack genes for the oxygen-evolving photosystem II and for carbon fixation, which has implications for oceanic carbon and nitrogen cycling and raises questions regarding the evolution of photosynthesis and N
2
fixation on Earth.
Influence of Common and Specific HLA-DRB1/DQB1 Haplotypes on Genetic Susceptibilities of Three Distinct Arab Populations to Type 1 Diabetes
Authors: Stayoussef Mouna , Benmansour Jihen , Al-Jenaidi Fayza A. , Nemr Rita , Ali Muhallab E. , Mahjoub Touhami , Almawi Wassim Y.
Published: November 2008

The contribution of HLA DRB-DQB to type 1 diabetes (T1D) in Bahrainis, Lebanese, and Tunisians was investigated.
DRB1*030101-DQB1*0201
was a locus that conferred susceptibility in three populations, while
DRB1*040101-DQB1*0302
was a locus that conferred susceptibility only in Tunisians and Bahrainis. The
DRB1*100101-DQB1*050101
(Bahrainis) and
DRB1*150101-DQB1*060101
(Lebanese) loci were largely protective. The contribution of HLA to T1D must be evaluated with regard to ethnic background.
Pediatric Antibody Response to Community-Acquired
Staphylococcus aureus
Infection Is Directed to Panton-Valentine Leukocidin
Authors: Brown Eric L. , Bowden M. Gabriela , Bryson Rebecca S. , Hulten Kristina G. , Bordt Andrea S. , Forbes Andrea , Kaplan Sheldon L.
Published: November 2008

We examined the antibody responses of pediatric patients infected with community-associated
Staphylococcus aureus
isolates. The data show that patients infected with Panton-Valentine leukocidin (PVL)-positive strains developed a dominant immunoglobulin G anti-PVL antibody response that correlates with markers of inflammation.
Confirmation of Rubella within 4 Days of Rash Onset: Comparison of Rubella Virus RNA Detection in Oral Fluid with Immunoglobulin M Detection in Serum or Oral Fluid
Authors: Abernathy Emily , Cabezas Cesar , Sun Hong , Zheng Qi , Chen Min-hsin , Castillo-Solorzano Carlos , Ortiz Ana Cecilia , Osores Fernando , Oliveira Lucia , Whittembury Alvaro , Andrus Jon K. , Helfand Rita F. , Icenogle Joseph
Published: November 2008

Rubella virus infection is typically diagnosed by the identification of rubella virus-specific immunoglobulin M (IgM) antibodies in serum, but approximately 50% of serum samples from rubella cases collected on the day of rash onset are negative for rubella virus-specific IgM. The ability to detect IgM in sera and oral fluids was compared with the ability to detect rubella virus RNA in oral fluids by reverse transcription-PCR (RT-PCR) by using paired samples taken within the first 4 days after rash onset from suspected rubella cases during an outbreak in Perú. Sera were tested for IgM by both indirect and capture enzyme immunoassays (EIAs), and oral fluids were tested for IgM by a capture EIA. Tests for IgM in serum were more sensitive for the confirmation of rubella than the test for IgM in oral fluid during the 4 days after rash onset. RT-PCR confirmed more suspected cases than serum IgM tests on days 1 and 2 after rash onset. The methods confirmed approximately the same number of cases on days 3 and 4 after rash onset. However, a few cases were detected by serum IgM tests but not by RT-PCR even on the day of rash onset. Nine RT-PCR-positive oral fluid specimens were shown to contain rubella virus sequences of genotype 1C. In summary, RT-PCR testing of oral fluid confirmed more rubella cases than IgM testing of either serum or oral fluid samples collected in the first 2 days after rash onset; the maximum number of confirmations of rubella cases was obtained by combining RT-PCR and serology testing.
Cryptosporidium
Genotype and Subtype Distribution in Raw Wastewater in Shanghai, China: Evidence for Possible Unique
Cryptosporidium hominis
Transmission
Authors: Feng Yaoyu , Li Na , Duan Liping , Xiao Lihua
Published: November 2008

To identify the genotype and subtype distributions of
Cryptosporidium
oocysts in domestic wastewater in Shanghai, China, and to facilitate the characterization of the endemic transmission of cryptosporidiosis, raw domestic wastewater samples were collected from four wastewater treatment plants in Shanghai, China, from December 2006 to April 2007. Genotypes of
Cryptosporidium
species were detected based on PCR-restriction fragment length polymorphism and sequence analyses of the small-subunit rRNA gene. Samples that contained
Cryptosporidium hominis
were further subtyped by DNA sequencing of the 60-kDa glycoprotein gene. Among a total of 90 samples analyzed, 63 were PCR positive, 10 of which had mixed genotypes. Fifty-nine (93.7%) of the PCR-positive samples had
C. hominis
, and 7 (11.1%) had
C. meleagridis
. The other seven
Cryptosporidium
species/genotypes identified included
C. baileyi
,
C. parvum
,
C. suis
,
C. muris
, rat genotype, avian genotype III, and a novel genotype. Forty-seven of the 59
C. hominis
-positive samples were successfully subtyped, with 29 having subtype family Ib and the remaining belonging to subtype families Ia, Id, Ie, and If. The three Ib subtypes identified, IbA19G2, IbA20G2, and IbA21G2, were very different from the two common Ib subtypes (IbA9G3 and IbA10G2) found in other areas of the world. Likewise, the Ie subtype IeA12G3T3 was also different from the common IeA11G3T3 subtype. Thus, the presence of multiple subtype families and unique Ib, Ie, and If subtypes indicates that there might be endemic transmission of cryptosporidiosis in the study area and that
C. hominis
populations there might be very different from those in other areas.
Pre-P Is a Secreted Glycoprotein Encoded as an N-Terminal Extension of the Duck Hepatitis B Virus Polymerase Gene
Authors: Cao Feng , Scougall Catherine A. , Jilbert Allison R. , Tavis John E.
Published: November 2008

The duck hepatitis B virus (DHBV) pregenomic RNA is a bicistronic mRNA encoding the core and polymerase proteins. Thirteen AUGs (C2 to C14) and 10 stop codons (S1 to S10) are located between the C1 AUG for the core protein and the P1 AUG that initiates polymerase translation. We previously found that the translation of the DHBV polymerase is initiated by ribosomal shunting. Here, we assessed the biosynthetic events after shunting. Translation of the polymerase open reading frame was found to initiate at the C13, C14, and P1 AUGs. Initiation at the C13 AUG occurred through ribosomal shunting because translation from this codon was cap dependent but was insensitive to blocking ribosomal scanning internally in the message. C13 and C14 are in frame with P1, and translation from these upstream start codons led to the production of larger isoforms of P. We named these isoforms “pre-P” by analogy to the pre-C and pre-S regions of the core and surface antigen open reading frames. Pre-P was produced in DHBV16 and AusDHBV-infected duck liver and was predicted to exist in 80% of avian hepadnavirus strains. Pre-P was not encapsidated into DHBV core particles, and the viable strain DHBV3 cannot make pre-P, so it is not essential for viral replication. Surprisingly, we found that pre-P is an N-linked glycoprotein that is secreted into the medium of cultured cells. These data indicate that DHBV produces an additional protein that has not been previously reported. Identifying the role of pre-P may improve our understanding of the biology of DHBV infection.
Analysis of the Differential Host Cell Nuclear Proteome Induced by Attenuated and Virulent Hemorrhagic Arenavirus Infection
Authors: Bowick Gavin C. , Spratt Heidi M. , Hogg Alison E. , Endsley Janice J. , Wiktorowicz John E. , Kurosky Alexander , Luxon Bruce A. , Gorenstein David G. , Herzog Norbert K.
Published: November 2008

Arenaviruses are important emerging pathogens and include a number of hemorrhagic fever viruses classified as NIAID category A priority pathogens and CDC potential biothreat agents. Infection of guinea pigs with the New World arenavirusPichindé virus(PICV) has been used as a biosafety level 2 model for theLassa virus. Despite continuing research, little is known about the molecular basis of pathogenesis, and this has hindered the design of novel antiviral therapeutics. Modulation of the host response is a potential strategy for the treatment of infectious diseases. We have previously investigated the global host response to attenuated and lethal arenavirus infections by using high-throughput immunoblotting and kinomics approaches. In this report, we describe the differential nuclear proteomes of a murine cell line induced by mock infection and infection with attenuated and lethal variants of PICV, investigated by using two-dimensional gel electrophoresis. Spot identification using tandem mass spectrometry revealed the involvement of a number of proteins that regulate inflammation via potential modulation of NF-κB activity and of several heterogeneous nuclear ribonuclear proteins. Pathway analysis revealed a potential role for transcription factor XBP-1, a transcription factor involved in major histocompatibility complex II (MHC-II) expression; differential DNA-binding activity was revealed by electrophoretic mobility shift assay, and differences in surface MHC-II expression were seen following PICV infection. These data are consistent with the results of several previous studies and highlight potential differences between transcriptional and translational regulation. This study provides a number of differentially expressed targets for further research and suggests that key events in pathogenesis may be established early in infection.
Overexpression of Interleukin-15 Compromises CD4-Dependent Adaptive Immune Responses against Herpes Simplex Virus 2
Authors: Gill Navkiran , Ashkar Ali A.
Published: November 2008

Interleukin-15 (IL-15) is necessary for the development and function of NK/NKT cells and the maintenance of naive and memory CD8
+
T cells. In the absence of IL-15, protective innate immunity is not available; however, a functional adaptive immune response against vaginal herpes simplex virus 2 (HSV-2) is generated. Mice overexpressing IL-15 (IL-15tg mice) have higher numbers of NK cells, greater NK-derived gamma interferon, and more CD8
+
T cells. Here we examined the consequences of IL-15 overexpression for innate and adaptive immunity against genital HSV-2. Surprisingly, IL-15tg mice immunized against HSV-2 were not protected against genital HSV-2 challenge compared to control immunized mice. IL-15tg mice had a higher frequency of NK cells in the genital mucosa than control mice. However, immunized IL-15tg mice had significantly lower numbers of HSV-2-specific CD4
+
T cells than B6 mice. We then confirmed that CD4
+
T cells, but not CD8
+
T cells, are essential for protection against intravaginal HSV-2 challenge. Since we observed less protection in immunized IL-15tg mice, we then examined if the adaptive immune responses generated in an environment with overexpression of IL-15 could provide protection against HSV-2 in an environment with normal levels of IL-15 expression. We adoptively transferred immunized cells from IL-15tg and B6 mice into naive RAG-1
−/−
mice and found that the cells from immunized IL-15tg mice were able to provide protection in this IL-15-normal environment. Our data suggest that overexpression of IL-15 results in a reduced CD4
+
T cell-mediated adaptive immune response against genital HSV-2.
Differential Sensitivity of “Old” versus “New” APOBEC3G to Human Immunodeficiency Virus Type 1 Vif
Authors: Goila-Gaur Ritu , Khan Mohammad A. , Miyagi Eri , Strebel Klaus
Published: November 2008

HIV-1 Vif counteracts the antiviral activity of APOBEC3G by inhibiting its encapsidation into virions. Here, we compared the relative sensitivity to Vif of APOBEC3G in stable HeLa cells containing APOBEC3G (HeLa-A3G cells) versus that of newly synthesized APOBEC3G. We observed that newly synthesized APOBEC3G was more sensitive to degradation than preexisting APOBEC3G. Nevertheless, preexisting and transiently expressed APOBEC3G were packaged with similar efficiencies into
vif
-deficient human immunodeficiency virus type 1 (HIV-1) virions, and Vif inhibited the encapsidation of both forms of APOBEC3G into HIV particles equally well. Our results suggest that HIV-1 Vif preferentially induces degradation of newly synthesized APOBEC3G but indiscriminately inhibits encapsidation of “old” and “new” APOBEC3G.
The rotated-lamina syndrome. II. The seedling of Ulmus glabra
Authors: Charlton W. A.
Published: November 2008

Seedlings of Ulmus glabra show heteroblastic development of the plumular axis, involving a change from an initial radial symmetry with leaves in decussate pairs to dorsiventral symmetry with distichously arranged foliage leaves displaying the rotated-lamina syndrome. The change is very variable in detail. The change to distichy usually precedes the appearance of the rotated-lamina syndrome and is usually accompanied by the formation of one or more bud scales. Contrary to an earlier suggestion, there is no anisophyllous phase of development. Axillary buds in the radially symmetrical region of the seedling also show heteroblastic development but have distichous phyllotaxis from the beginning. During the first growing season they initiate a small number of bud scales and then a series of foliage leaves showing progressively accentuated development of the rotated-lamina syndrome. Some early foliage leaves show evidence of rotation of the lamina region by torsion. This is not detectable in later leaves in the seedling or in adult shoots, and it is suggested that the rotated-lamina syndrome may have arisen by heterochronic shift of the rotation process into progressively earlier stages of leaf development. Key words: Ulmus glabra, seedling, leaf, development, dorsiventrality.
Taxonomic studies of marine Ascomycotina: ultrastructure of the asci, ascospores, and appendages of Savoryella species
Authors: Read Susan J. , Jones E. B. Gareth , Moss Stephen T.
Published: November 2008

The asci, ascospores, and appendages of Savoryella longispora, Savoryella paucispora, and Savoryella appendiculata were examined at the transmission electron microscope level. Asci of S. longispora and S. appendiculata have a well-developed apical apparatus that consists of a thickened electron-dense ring with a central pore. In S. appendiculata the pore is occluded by a plug of electron-lucent material. The ascus wall comprises an outer narrow electron-opaque layer and an inner electron-lucent layer that are continuous over the apical apparatus. Ascospore walls possess an inner electron-lucent mesosporium and an outer electron-opaque episporium. The episporium of the central cells of all three species is covered with a layer of fibrillar mucilage. Granular strand-like outgrowths of the ascospore wall are present on the polar cells of S. appendiculata and S. paucispora. In all three species the hyaline polar cells of the ascospore contain organelles and in S. appendiculata the polar cells are verrucose. Ascospore appendages are only found in S. appendiculata and these arise endogenously by outgrowth of the endosporium of the polar cell. The differences between the three species are not considered significant at the generic level and therefore all are assigned to the genus Savoryella. Key words: appendages, Ascomycotina, ascospores, marine, taxonomy, ultrastructure.
X-ray microanalysis of frozen-hydrated, freeze-dried, and critical point dried leaf specimens: determination of soluble and insoluble chemical elements at Erysiphe graminis epidermal cell papilla sites in barley isolines containing Ml-o and ml-o alleles
Authors: Zeyen R. J. , Ahlstrand G. G. , Carver T. L. W.
Published: November 2008

Three specimen preparation procedures were used in conjunction with scanning electron microscopy and energy dispersive X-ray microanalysis to determine, by comparison among preparation methods, both soluble and insoluble elements at Erysiphe graminis – barley leaf epidermal cell encounter site areas where attempted fungal penetration by appressoria failed. Near isogenic lines (RISO 5678-R and RISO 5678-S) of barley differing by mutation at the Ml-o locus were used. The recessive ml-o allele conditions barley epidermal cells to respond with papilla-associated resistance to E. graminis, while the dominant Ml-o allele allows for successful penetration of the majority of E. graminis germlings. Frozen-hydrated and freeze-dried specimens maintained soluble and insoluble elements, while specimens fixed by formalin – acetic acid – alcohol and critical point dried lost soluble elements. The effects of specimen preparation on electron-beam penetration and depth of X-ray excitation were calculated and are illustrated. Mean elemental intensity values were corrected for X-ray absorption by nickel coating of specimens (used for electrical conductivity) and for X-ray detector efficiency. The elements Cl, K, Mn, Ca, and Mg were highly soluble both at recently deposited (16 h) and at matured (24 h) papilla deposition sites. Elemental Si levels were elevated and in a partially soluble state in recently deposited papilla sites (16 h), but Si became bound or insoluble in matured (24 h) papilla sites. Elemental P and S are insoluble. The physiological role of each element is briefly discussed relative to its known function in healthy and diseased plants, with emphasis on E. graminis – barley epidermal cell encounter site penetration failure. Key words: Erysiphe graminis, Hordeum vulgare, X-ray microanalysis, scanning electron microscopy.
Heat stress during reproduction in summer rape
Authors: Morrison M. J.
Published: November 2008

Summer rape (Brassica napus cvs. Delta and Westar) plants were grown from seed to maturity in controlled environment cabinets set to hot (27:17 °C, light:dark) and cold (22:15 °C) temperatures. Plants were transferred from the cabinet of origin to the opposite cabinet at different phenological stages. Cross pollination between plants in hot and cold cabinets served to isolate the reproductive organ most sensitive to heat stress. Brassica napus was sterile in controlled environment cabinets with maximum temperatures exceeding 27 °C. In flowers grown in the cold cabinet, the gynoecium extended through the ring of anthers at anthesis, while in heat stressed flowers, the gynoecium was always longer than the anthers. Plants were most sensitive to heat stress from late bud development through to early seed formation. Preanthesis hot temperatures reduced pollen fertility and caused a reduction in female fertility. Postanthesis hot temperatures decreased the female fertility. Key words: temperature stress, male and female sterility, Brassica napus.
The seed rain and seed bank of an adjacent native tallgrass prairie and old field
Authors: Schott Gary W. , Hamburg Steven P.
Published: November 2008

The ability of a grassland to regenerate following disturbance depends on the presence of seeds of native plants and the ability of the seeds to germinate. To examine whether the presence or absence of plant propagules influences reestablishment of tallgrass prairie on abandoned agricultural lands, we sampled the seed rain and soil seed bank across a transition from native tallgrass prairie to unmanaged successional grassland (old field). The native prairie seed rain was seven times greater than that of the old field, richer in species (33 vs. 27), and more diverse (diversity index 0.96 vs. 0.73). In addition, the native tallgrass prairie seed bank was three times as dense as the old-field seed bank and contained the seeds of more species (23 vs. 19), but had a lower index than did the old field (0.81 vs. 1.08). One species, Sphenopholis obtusata, present in the prairie, was observed dispersing to the old-field plot, but was absent in the old-field plot; this observation suggests that at least some species are unable to establish on the old-field plot. Thus, the ability of a native grassland to reestablish may be limited by the dispersal ability of native species and the ability to establish once dispersed. Key words: seed rain, seed bank, native tallgrass prairie, old-field succession.
Pollen limitation in an experimental population of the wild radish Raphanus raphanistrum
Authors: Pfennig Karin S. , Conner Jeffrey K.
Published: November 2008

Experimental hand-pollinations were performed on a sample of wild radish, Raphanus raphanistrum, to determine whether female reproductive success was pollen limited. Fruit set was found to increase with receipt of supplemental pollen, but seed set did not. These results contradict findings in another Raphanus species but are expected if seeds are aborted or matured in packages. Key words: pollen limitation, Raphanus raphanistrum, female fitness.
Responses of the Norwegian alpine Betula nana community to nitrogen fertilization
Authors: Paal Jaanus , Fremstad Eli , Möls Tõnu
Published: November 2008

The effect of nitrogen fertilization on species cover, increment of shrubs, tissue nitrogen, and soil parameters was tested during a 3-year experiment in a low alpine plant community dominated by Betula nana in the Dovre mountains, south-central Norway. The doses used were 1.2 and 6.1 g N/m2, corresponding to 0.72 and 3.6 times, respectively, the annual deposition of nitrogen in southwest Norway. Statistical analysis using SAS ANOVA and GLM procedures were applied to different types of models. The cover of species and growth forms showed no significant response to additional nitrogen supply. The increment of shrubs was not significantly affected by the fertilization, except for the year factor. Incorporation of nitrogen into plant tissue was not evident. No effects were found on soil parameters. Key words: fertilization, alpine tundra, shrubs, nitrogen.
The soil propagule bank in a boreal old-growth spruce forest: changes with depth and relationship to aboveground vegetation
Authors: Rydgren Knut , Hestmark Geir
Published: November 2008

The species composition and the depth distribution of the soil propagule banks of bryophytes and vascular plants from three different soil layers in a boreal old-growth spruce forest in SE Norway were studied using the emergence method. A total of 34 taxa germinated with a predominance of ferns and mosses. The frequency of the different species exhibits a common community pattern with a few common and a large number of low frequency species. The tree Betula pubescens, the ferns Athyrium filix-femina, Gymnocarpium dryopteris, and Phegopteris connectilis, and the mosses Plagiothecium laetum agg. and Polytrichum spp. were the most frequent. There is only a moderate correspondence, decreasing with soil depth, between the propagule bank and the aboveground vegetation in the sampled plots. In the soil profile, the litter layer on average had more taxa than the peaty mor and bleached layer (7.7, 6.0, and 5.5 taxa, respectively). Five of the 17 taxa occurring in more than 10% of the soil samples from the different soil layers were significantly more frequent in the upper soil layer, while two taxa were more frequent in either peaty mor and (or) the bleached layer than in the uppermost layer. The propagule bank in the different soil layers represents an in situ potential for regeneration of the vegetation after different degrees of disturbance in the forest floor. Key words: disturbance, soil propagule bank, boreal forest, bryophytes, vascular plants.
Modifications of host cells and tissues by the biotrophic endophyteEpichloë amarillans(Clavicipitaceae; Ascomycotina)
Authors: White Jr. James F. , Bacon Charles W. , Hinton Dorothy M.
Published: November 2008

The Clavicipitaceae (Ascomycotina) are unique among biotrophs in that they do not produce haustoria to extract nutrients from hosts. Stromata are usually formed on developing parts of the host and are composed of a mixture of host and fungal tissues. An ultrastructural examination of stromata of Epichloë amarillans was conducted to assess changes in host tissues associated with development of stromata on grasses. Notable changes were observed in the epidermal layers of leaves and inflorescence primordia embedded within stromata. Epidermal cells within stromata showed progressive disintegration of the cuticle and wall layers. These alterations effectively broke down the epidermal barrier to the flow of nutrients and water to fungal tissues that develop outside the plant tissues. Mycelium was observed to associate closely with host cells. No penetrations of cells of the mesophyll, phloem, or xylem were observed; however, some alteration of the host cell walls was detected. Host cell walls proximal to hyphae were often seen to be slightly thicker than walls adjacent to other plant cells. Unseen alterations to host cell membranes are hypothesized. A mechanism of nutrient flow from host to stromal mycelium is discussed. The modification of host cells and tissues to enhance nutrient flow to fungal reproductive structures, without the development of haustoria, is suggested to be a basic mechanism of nutrient acquisition among biotrophic fungi. Key words: Clavicipitaceae, endophyte, Epichloë, nutrient acquisition, ultrastructure.
Regulation of sweetpotato growth and differentiation by glutamate dehydrogenase
Authors: Osuji G. O. , Madu W. C.
Published: November 2008

The function of glutamate dehydrogenase was studied in cultured sweetpotato (Ipomoea batatas) nodal explants. The glutamate dehydrogenase was fractionated to charge isomers. Supplementation of the growth medium with either naphthaleneacetic acid or benzyladenine in the presence of 20 mM NH4NO3induced normal growth (type 1 sweetpotato). The basic and acidic charge isomers of glutamate dehydrogenase were not suppressed. Combined supplementation with 70 mM NH4+and either 1 mg ∙ L−1benzyladenine or 0.1 mg ∙ L−1naphthaleneacetic acid caused growth retardation (type 2 sweetpotato) and the suppression of the basic charge isomers. Combined supplementation with 45 mM NH4+and either 1 mg ∙ L−1benzyladenine or 0.1 mg ∙ L−1naphthaleneacetic acid induced normal growth (type 3 sweetpotato), but the acidic charge isomers were suppressed. Combined supplementation with benzyladenine and naphthaleneacetic acid suppressed all the charge isomers and abolished amination by the enzyme, thereby causing severe growth retardation. The type 1 and type 3 sweetpotato glutamate dehydrogenases were more aminating (Michaelis constant Km = 12.5 and 14.8 mM NH4Cl, respectively) than type 2 sweetpotato glutamate dehydrogenase (Km = 82.6 mM NH4Cl). The differential growth retardations which accompanied the three phases of the suppression of the aminating charge isomers are evidence that the enzyme is aminating in vivo and that it employed that activity in the regulation of sweetpotato growth and differentiation. Key words: glutamate dehydrogenase, amination depression, sweetpotato retardation.
Apparition de l'asymétrie foliaire chez les plantules du Begonia subvillosa et du B. fagifolia (Begoniaceae)
Authors: Thibeault Geneviève , Barabé Denis , Brouillet Luc
Published: November 2008

The leaves of the majority of Begonia species are asymmetrical. To shed some light on the nature of this asymmetry, the authors followed the development of the first forming leaves in two species with very different adult shapes: Begonia subvillosa, which has strongly asymmetrical leaves and palmate venation, and B. fagifolia, which has pinnate venation and symmetrical leaves. Key stages of the development were identified. First, there is no asymmetry within the embryo. In both species, the leaves of the first two nodes are asymmetrical in the early stages. However, they lose this asymmetry during development and show a palmate venation. From the third node on, the two species show some differences. The leaf of B. subvillosa keeps its initial asymmetry and part of its blade develops into an auricle, unlike the leaf of B. fagifolia. From the fourth node on, the leaf of B. fagifolia is pinnately veined. The central area of the leaf blade of both species settles to its adult shape much earlier in development than other areas of the leaf. The different parts of the blade acquire their adult characteristics successively according to different timing sequences. Key words: Begoniaceae, development, leaf, morphogenesis, symmetry.
Restoration techniques for Sphagnum-dominated peatlands
Authors: Ferland Chantale , Rochefort Line
Published: November 2008

Ombrotrophic peatlands in North America are harvested mainly for horticultural purposes. Following intense exploitation, these peatlands are generally abandoned to natural regeneration. The abandoned sites usually remain barren or poorly revegetated by a few vascular plants for several years. The post-harvested sites are not usually recolonized by Sphagnum species (peat mosses), which are the key species to restore peatland functions. The objective of this study was to develop restoration techniques for post-harvested peatlands. The experiments centred on Sphagnum reintroduction, since peat mosses are responsible for peat accumulation. Vegetative Sphagnum fragments were used as diaspores. Various methods of Sphagnum reintroduction were tested to ensure reliable colonization. A microrelief formed of ridges and depressions provided humid conditions in depressions which favored Sphagnum establishment. Reintroducing Sphagnum diaspores in combination with such companion plant species as Eriophorum angustifolium also had a positive effect on the survival of peat mosses. A phosphorus amendment led to improved establishment of Sphagna and companion plant species. Key words: Sphagnum, microtopography, companion species, phosphorus, fertilization.
Light and electron microscopic and energy dispersive X-ray microanalysis studies of globoids in protein bodies of embryo tissues and the aleurone layer of rice (Otyza sativa L.) grains
Authors: Wada Tomikichi , Lott John N. A.
Published: November 2008

To understand the differences in mineral nutrient storage within tissues and organs of rice (Oryza sativa L.) grains, the distribution of globoids in rice embryo and endosperm tissues was examined using light and transmission electron microscopy and energy dispersive X-ray microanalysis was used to study globoid composition. Globoids were found in most embryo tissues, including provascular cells, and their location and size in sections of protein bodies is described. While P, Mg, and K were commonly detected in all globoids, other elements such as Ca, Mn, Fe, and Zn were sometimes detected in globoids of specific tissues and (or) regions. High peak-to-background ratios for P were obtained in globoids of scutellar and aleurone cells, and moderately high values were detected in ground meristem regions of the mesocotyl and coleoptile. Relatively high K levels were found in globoids in parenchyma cells of the scutellum and coleorhiza; in provascular cells of the radicle; and in ground meristem cells from the mesocotyl, coleoptile, and plumule. Calcium was mainly detected in globoids of the aleurone layer. Iron was mostly found in radicle tissue globoids. Zinc was commonly found in globoids of the scutellar epithelium and in provascular tissues of the mesocotyl, coleoptile, and radicle. Manganese was distributed throughout most of the tissues examined, but the highest levels of Mn were detected in globoids from the coleoptile tip regions and the plumule. A novel finding was that, in the provascular tissues of the coleoptile tip, distinctive differences were found in Mn, Fe, and Zn storage between globoids in the future xylem and the future phloem. Key words: EDX analysis, embryos, globoids, mineral storage, phytate, Oryza sativa, rice.
Suberin deposition and band plasmolysis in the corn (Zea maysL.) root exodermis
Authors: Enstone Daryl E. , Peterson Carol A.
Published: November 2008

The exodermal Casparian band in corn (Zea mays L.) was first seen 10 mm distal to the kernel 4 days after planting. From its inception, the band usually occupied most of the radial wall (as seen in a cross section of the root). Subsequent maturation of the band around the root was asynchronous into the region of emerging lateral roots. Thus, a continuous apoplastic barrier would have been absent over much of the young root surface. Suberin lamellae development was also asynchronous, as these structures formed in those cells which had Casparian bands. Frequently, a lamella was initially deposited in patches, progressing centripetally until a continuous lipid layer was formed around the cell protoplast. Many instances of band plasmolysis (typical of the endodermis) were observed in the developing uniform exodermis. It could occur in cells with no detectable Casparian bands, suggesting that the tight connection between the plasmalemma and the wall that causes this phenomenon is not due to hydrophobic attractions. The results are consistent with the idea that there are strong attractions between proteins of the membrane and wall in the region of the Casparian band. The tight connection between the plasmalemma and the wall was broken during the later stages of suberin lamella development. Key words: Zea mays L., Poaceae, band plasmolysis, exodermis, Casparian band, suberin lamella.
ABSORPTION CROSS-SECTION AND EMISSION SPECTRA OF SCHWARZSCHILD BLACK HOLE IN DIRAC FIELD
Authors: SINI R. , KURIAKOSE V. C.
Published: November 2008

The behavior of a Dirac field in a Schwarzschild black hole spacetime is studied. In this work the Hawking temperature and the absorption cross-section for Schwarzschild black hole placed in Dirac field are calculated, taking into consideration the matter waves reflected from the event horizon. The absorption cross-section σ abs in Dirac field is found to be ⅛ of absorption cross-section in scalar field. The emission spectra of Schwarzschild black hole placed in an environment of Dirac field is also obtained.
QUANTUM INFORMATION SPLITTING OF TWO-QUBIT STATE WITH MINIMAL CLASSICAL COMMUNICATION AND MEASUREMENT COMPLEXITY
Authors: PAN GUI-XIA , LIU YI-MIN , ZUO XUE-QIN , ZHANG WEN , ZHANG ZHAN-JUN
Published: November 2008

We present a quantum information splitting scheme of a two-qubit state by using two Greenberger–Horne–Zeilinger (GHZ) states as quantum channels. In this scheme, since the sender Alice knows the quantum information in priori, she only needs to perform a two-qubit measurement and publish two classical bits for her two agents Bob and Charlie to reconstruct the quantum information via their mutual assistance. We calculate the success probability and classical communication cost within the scheme. In the general case, Alice can successfully split the state with probability 25% (probabilistic) and the classical communication cost is 4 classical bits. However, in some special cases, the secret states are chosen from a special ensemble, the success probability of our scheme can be increased to 50% or even to 100% (deterministic) after consuming some extra classical bits.
Epigenetic Regulation of Transposable Elements in Plants
Authors: Lisch Damon
Published: November 2008

Transposable elements make up a substantial proportion of most plant genomes. Because they are potentially highly mutagenic, transposons are controlled by a set of mechanisms whose function is to recognize and epigenetically silence them. Under most circumstances this process is highly efficient, and the vast majority of transposons are inactive. Nevertheless, transposons are activated by a variety of conditions likely to be encountered by natural populations, and even closely related species can have dramatic differences in transposon copy number. Transposon silencing has proved to be closely related to other epigenetic phenomena, and transposons are known to contribute directly and indirectly to regulation of host genes. Together, these observations suggest that naturally occurring changes in transposon activity may have had an important impact on the causes and consequences of epigenetic silencing in plants.
Immune Therapy for Cancer
Authors: Dougan Michael , Dranoff Glenn
Published: November 2008

Over the past decade, immune therapy has become a standard treatment for a variety of cancers. Monoclonal antibodies, immune adjuvants, and vaccines against oncogenic viruses are now well-established cancer therapies. Immune modulation is a principal element of supportive care for many high-dose chemotherapy regimens. In addition, immune activation is now appreciated as central to the therapeutic mechanism of bone marrow transplantation for hematologic malignancies. Advances in our understanding of the molecular interactions between tumors and the immune system have led to many novel investigational therapies and continue to inform efforts for devising more potent therapeutics. Novel approaches to immune-based cancer treatment strive to augment antitumor immune responses by expanding tumor-reactive T cells, providing exogenous immune-activating stimuli, and antagonizing regulatory pathways that induce immune tolerance. The future of immune therapy for cancer is likely to combine many of these approaches to generate more effective treatments.