bluuebunny/crossref_metadata_2025_split huggingface dataset:
Possible Role of Dimerization in Human Immunodeficiency Virus Type 1 Genome RNA Packaging
Authors: Sakuragi Jun-Ichi , Ueda Shigeharu , Iwamoto Aikichi , Shioda Tatsuo 
Published: March 2003

ABSTRACT
The dimer initiation site/dimer linkage sequence (DIS/DLS) region in the human immunodeficiency virus type 1 (HIV-1) RNA genome is suggested to play important roles in various steps of the virus life cycle. However, due to the presence of a putative DIS/DLS region located within the encapsidation signal region (E/psi), it is difficult to perform a mutational analysis of DIS/DLS without affecting the packaging of RNA into virions. Recently, we demonstrated that duplication of the DIS/DLS region in viral RNA caused the production of partially monomeric RNAs in virions, indicating that the region indeed mediated RNA-RNA interaction. We utilized this system to assess the precise location of DIS/DLS in the 5′ region of the HIV-1 genome with minimum effect on RNA packaging. We found that the entire lower stem of the U5/L stem-loop was required for packaging, whereas the region important for dimer formation was only 10 bases long within the lower stem of the U5/L stem-loop. The R/U5 stem-loop was required for RNA packaging but was completely dispensable for dimer formation. The SL1 lower stem was important for both dimerization and packaging, but surprisingly, deletion of the palindromic sequence at the top of the loop only partially affected dimerization. These results clearly indicated that the E/psi of HIV-1 is much larger than the DIS/DLS and that the primary DIS/DLS is completely included in the E/psi. Therefore, it is suggested that RNA dimerization is a part of RNA packaging, which requires multiple steps.
nef
Gene Is Required for Robust Productive Infection by Simian Immunodeficiency Virus of T-Cell-Rich Paracortex in Lymph Nodes
Authors: Sugimoto Chie , Tadakuma Kei , Otani Isao , Moritoyo Takashi , Akari Hirofumi , Ono Fumiko , Yoshikawa Yasuhiro , Sata Tetsutaro , Izumo Shuji , Mori Kazuyasu 
Published: March 2003

ABSTRACT

The pathogenesis of AIDS virus infection in a nonhuman primate AIDS model was studied by comparing plasma viral loads, CD4
+
T-cell subpopulations in peripheral blood mononuclear cells, and simian immunodeficiency virus (SIV) infection in lymph nodes for rhesus macaques infected with a pathogenic molecularly cloned SIVmac239 strain and those infected with its
nef
deletion mutant (Δnef). In agreement with many reports, whereas SIVmac239 infection induced AIDS and depletion of memory CD4
+
T cells in 2 to 3 years postinfection (p.i.), Δnef infection did not induce any manifestation associated with AIDS up to 6.5 years p.i. To explore the difference in SIV infection in lymphoid tissues, we biopsied lymph nodes at 2, 8, 72, and 82 weeks p.i. and analyzed them by pathological techniques. Maximal numbers of SIV-infected cells (SIV Gag
+
, Env
+
, and RNA
+
) were detected at 2 weeks p.i. in both the SIVmac239-infected animals and the Δnef-infected animals. In the SIVmac239-infected animals, most of the infected cells were localized in the T-cell-rich paracortex, whereas in the Δnef-infected animals, most were localized in B-cell-rich follicles and in the border region between the paracortex and the follicles. Analyses by double staining of CD68
+
macrophages and SIV Gag
+
cells and by double staining of CD3
+
T cells and SIV Env
+
cells revealed that SIV-infected cells were identified as CD4
+
T cells in either the SIVmac239 or the Δnef infection. Whereas the many functions of Nef protein were reported from in vitro studies, our finding of SIVmac239 replication in the T-cell-rich paracortex in the lymph nodes supports the reported roles of Nef protein in T-cell activation and enhancement of viral infectivity. Furthermore, the abundance of SIVmac239 infection and the paucity of Δnef infection in the T-cell-rich paracortex accounted for the differences in viral replication and pathogenicity between SIVmac239 and the Δnef mutant. Thus, our in vivo study indicated that the
nef
gene enhances SIV replication by robust productive infection in memory CD4
+
T cells in the T-cell-rich region in lymphoid tissues.
Latency of Viral Expression In Vivo Is Not Related to CpG Methylation in the U3 Region and Part of the R Region of the Long Terminal Repeat of Bovine Leukemia Virus
Authors: Tajima Shigeru , Tsukamoto Masako , Aida Yoko 
Published: March 2003

ABSTRACT

Bovine leukemia virus (BLV) is silent in most cells detectable in vivo, and the repression of its expression allows BLV to evade the host's immune response. In this study, we examined whether CpG methylation of DNA might be involved in the regulation of the expression of BLV in vivo. To investigate the effects of CpG methylation on the activity of the long terminal repeat (LTR) of BLV, we measured the transactivation activity of this region after treatment with the CpG methyltransferase
Sss
I by using a luciferase reporter system. The activity of methylated LTR was significantly lower than that of nonmethylated LTR. Therefore, we examined the extent of CpG methylation of the U3 region and part of the R region of the LTR in BLV-infected cattle and in experimentally BLV-infected sheep at various clinical stages by the bisulfite genomic sequencing method. We detected no or minimal CpG methylation at all stages examined in cattle and sheep, and our results indicate that CpG methylation probably does not participate in the silencing of BLV in vivo.
Polyprotein Processing Protease of African Swine Fever Virus: Purification and Biochemical Characterization
Authors: Rubio Daniel , Alejo Alí , Rodríguez Irene , Salas María L. 
Published: March 2003

ABSTRACT
The purified recombinant African swine fever virus polyprotein processing protease cleaves the two GG-X sites in polyprotein pp62 with the same efficiency. Cleavage at the site that is first recognized in vivo is not a requisite for cleavage at the second site, suggesting the existence of mechanisms that control the ordered processing of the polyprotein during infection.
Fabrication of electroluminescent devices using Sr as an electron injection layer
Authors: Tanaka Kuniaki , Miyagawa Eijiro , Usui Hiroaki 
Published: March 2003

AbstractStrontium (Sr) was evaporated on tris (8‐quinolinolato) aluminum (Alq) to form an electron injection layer for organic electroluminescence (EL) device. Chemical status of Sr was examined by x‐ray photoelectron spectroscopy (XPS). EL devices having the structure of ITO/PVCz:p‐TPD/Alq/Sr/Al were prepared and their luminance and lifetime were measured. It was found that EL characteristics could be improved by depositing metallic Sr layer at a deposition rate higher than 0.7 nm/s. XPS analysis showed that Sr interdiffuses into Alq when the Sr thickness exceeds 40 nm, which caused red shift of luminescence spectra by 10 nm. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(4): 36–41, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.1121
The second derivative of the dose–time–response surface as a measure of DNA repair kinetics in the comet assay
Authors: Kim Byung‐Soo , Park Jin Joo , Edler Lutz , Fournier Dietrich von , Haase Wulf , Sautter‐Bihl Marie‐Luise , Gotzes Florian , Thielmann Heinz Walter 
Published: March 2003

AbstractThe comet assay is a sensitive and rapid method for detecting DNA damage and repair of damage in individual cells. It has been widely used in genetic toxicology, environmental biomonitoring, molecular and human epidemiology and clinical investigations, since it was first introduced by Östling and Johanson in 1984 and independently modified by Singh et al. and Olive et al. There are still several issues that have to be resolved before the comet assay is accepted as a standard assay for detecting DNA damage/repair in a single cell. One of the major issues is the proper quantification of DNA repair kinetics. This article develops a new quantitative measure of the DNA repair kinetics which is represented in the dose–time–response surface. For measuring the DNA repair kinetics, we propose to use the second derivative, 2D, of the dose–time–response surface. This approach enables us to represent with a single number the DNA repair activity of cells exposed to ionizing radiation, by combining all the information in the experiment. The computation procedure includes the application of linear regression. In our application to the assessment of radiation sensitivity of patients we considered for the response four DNA damage parameters, i.e. the tail moment, the tail length, the tail DNA and the tail inertia for constructing the dose–time–response surface. Based on the data from 25 patients we observed that the second derivatives based on the tail moment and the tail DNA showed high correlation and that the tail inertia might express a somewhat different aspect of the DNA damage/repair. Copyright © 2003 John Wiley & Sons, Ltd.
Metabolic abnormalities (hypertension, hyperglycemia and overweight), lifestyle (high energy intake and physical inactivity) and endometrial cancer risk in a Norwegian cohort
Authors: Furberg Anne‐Sofie , Thune Inger 
Published: March 2003

AbstractSince high energy intake, inactivity, hypertension and diabetes are linked to obesity and an unfavorable hormonal profile, we wanted to test whether energy intake, physical activity, blood pressure and serum glucose are related to the risk of endometrial cancer independent of the body mass index (BMI). A cohort of 24,460 women, aged 20–49 years, attended a Norwegian health screening twice during 1974–1981; they answered questions about diet, physical activity and chronic diseases, and their height, weight, blood pressure and non‐fasting serum glucose were measured. By the end of 1996, during 15.7 years of follow‐up, 130 cases of endometrial carcinomas were identified. The relative risks (RRs) for endometrial cancer were estimated in proportional hazards models including potentially confounding factors. Obese women (BMI ≥ 30 kg/m2) were at 2.6 times increased risk of endometrial cancer compared to normal weight women (BMI < 25 kg/m2) (RR = 2.57, 95%CI = 1.61–4.10). Among overweight women (BMI ≥ 25 kg/m2), non‐fasting serum glucose in the upper quartile vs. in the lower quartile was associated with a 2.4 times increase in risk (RR = 2.41, 95%CI = 1.08–5.37), whereas among obese women, blood pressure above 140/90 mmHg vs. below 140/90 mmHg in both surveys was associated with a 3.5 times increase in risk (RR = 3.47, 95%CI = 1.24–9.70). Especially in women younger than 50 years, high energy intake (5,044–6,401 kJ/day) conferred higher risk compared to low energy intake (< 4266 kJ/day) (RR = 3.40, 95%CI = 1.52–7.60). Increasing recreational activity tended to be protective. Among obese women with non‐sedentary jobs at both screenings, RR declined to 0.18 (95%CI = 0.05–0.62) as the level of sustained occupational activity increased (ptrend = 0.03). Our results suggest that inactivity and high energy intake are major risk factors for endometrial cancer independent of BMI, and that hypertension and relative hyperglycemia are significant markers of risk, especially among the heaviest women. © 2003 Wiley‐Liss, Inc.
A special report: histocompatibility testing guidelines for hematopoietic stem cell transplantation using volunteer donors *
Authors: Hurley C.K. , Wade J.A. , Oudshoorn M. , Middleton D. , Kukuruga D. , Navarrete C. , Christiansen F. , Hegland J. , Ren E.‐C. , Andersen I. , Cleaver S.A. , Brautbar C. , Raffoux C. 
Published: March 2003

Abstract:The World Marrow Donor Association has formulated guidelines for establishing the extent and quality of histocompatibility testing for unrelated donor registries, umbilical cord blood banks, and transplant centers involved in international exchange of hematopoietic stem cells for allogeneic transplantation. Registry and cord blood bank guidelines suggest that, at a minimum, initial HLA typing should be performed for three HLA loci, HLA‐A, ‐B, and ‐DR, at low resolution/split antigen level. DNA‐based testing methods should be utilized for HLA‐DR typing. DNA‐based testing for HLA‐A and ‐B should replace serologic testing of new volunteer donors and cord blood units as robust protocols and reagents become available to the laboratories. Transplant center guidelines for typing of patient, family and to confirm the HLA types of potential unrelated donors should include, at the minimum, typing HLA‐A, B, and ‐DR loci using primarily DNA‐based testing methods at allele level resolution for DRB1 and low resolution/split antigen level for HLA‐A and ‐B. It is strongly recommended that the typing of a patient and the selected donor be performed using the same set of reagents, methodology, and interpretation criteria with fresh tissue samples to ensure HLA identity. Guidelines for laboratory accreditation, approaches to quality assurance and quality control for HLA testing, and suggestions for the format of the HLA database of donor types are also outlined.
The CC‐chemokine receptor 5 (CCR5) is a marker of, but not essential for the development of human Th1 cells
Authors: Ødum N. , Bregenholt S. , Eriksen K.W. , Skov S. , Ryder L.P. , Bendtzen K. , Van Neerven R.J.J. , Svejgaard A. , Garred P. 
Published: March 2003

Abstract:The CC‐chemokine receptor 5 (CCR5) has recently been described as a surface marker of human T cells producing type 1 (Th1) cytokines. Here we confirm that CCR5 is expressed on human Th1 but not on Th2 T‐cell clones. Using intracellular cytokine staining, we show that allo‐antigen specific CD4+ T‐cell lines derived from a CCR5‐deficient individual (Δ32 allele homozygote) contain high numbers of both interferon γ (IFN‐γ) and interleukin (IL)‐2 producing cells, low numbers of IL‐10 producing cells and no IL‐4 or IL‐5 producing cells when stimulated with phorbol ester and ionomycin in vitro. These results were similar to those obtained from allo‐antigen specific CD4+ T‐cell lines derived from CCR5 expressing individuals. An enzyme‐linked immunoabsorbent assay (ELISA) confirmed that the Th1 cytokine‐positive cells from the CCR5‐deficient individual were able to produce equal amounts of cytokines when compared to T‐cell lines from CCR5‐expressing individuals. These results demonstrate that CCR5‐negative T cells display the same capacity of Th1 T‐cell differentiation as T cells derived from CCR5‐expressing individuals. Thus, CCR5 expression is not essential for differentiation of human Th1 T cells.
Identification of the null HLA‐A2 allele, A*0232N
Authors: Bunce M. , Procter J. , Dunn P.P.J. , Day S. , Ross J. , Welsh K.I. 
Published: March 2003

Abstract:We have identified a null HLA‐A*02 allele, HLA‐A*0232N, by using a combination of serology, flow cytometry, polymerase chain reaction using sequence‐specific primers (PCR‐SSP) and full‐length sequencing. The null HLA‐A2 allele was identified in an Asian individual originally typed by serology as an apparently homozygous HLA‐A3, B51. Subsequent genotyping by PCR‐SSP identified the genotype as HLA‐A*0201, *0301, B*51, Cw*1402. The serological type and lack of detectable HLA‐A2 was confirmed using monoclonal antibody typing reagents. Flow cytometry studies failed to identify any cell surface HLA‐A2 expression on the patient’s peripheral blood lymphocytes. Genotyping using a PCR‐SSP set designed to detect null alleles revealed the mutation had not been previously described. Full‐length sequencing of the allele identified an allele which was subsequently named HLA‐A*0232N. This allele is identical to HLA‐A*0201 except for a novel point mutation (T for C) at position 493 which creates a premature stop codon. The sequencing enabled the development of a monospecific A*0232N PCR‐SSP reaction which was used to screen 973 DNA samples: no further examples of A*0232N were identified.
HLA‐B*4413 identified in a UK Caucasoid potential bone marrow donor
Authors: Cox S.T. , McWhinnie A. , Prokupek B. , Madrigal J.A. , Little A.‐M. 
Published: March 2003

Abstract:We describe a novel allele belonging to the B*44 allele group. HLA‐B*4413 was identified in a Caucasoid potential bone marrow donor from the Anthony Nolan Bone Marrow Trust register. Initial HLA typing of this donor revealed unusual serological reactivity. Further investigation was carried out by reference strand conformation analysis (RSCA) and sequence‐based typing (SBT) using DNA extracted from an Epstein‐Barr virus (EBV)‐transformed B‐cell line made from this donor (AMI005AN). In this individual, two B*44 alleles were revealed upon initial investigation: B*4409 and a previously unseen allele which has been named B*4413. B*4413 is identical to B*44031 except for a unique nucleotide substitution resulting in an amino acid difference at residue 61 in the α1 helix ( Note).
The relationship between HLA‐B45 and B*5002 in the five major U.S. population groups
Authors: Kosman C. , Steiner N. , Pulyaeva H. , Mitton W. , Slack R. , Hartzman R.J. , Ng J. , Hurley C.K. 
Published: March 2003

Abstract:The antigen encoded by B*5002 differs in sequence from that encoded by B*5001 only at amino acid residue 167 (consensus tryptophan vs. serine) which results in B45 serologic reactivity. To search for B*5002, the frequencies of alleles encoding the serologically defined B45 antigen were determined by sequence‐based typing in 5 major U.S. populations: Caucasians, African Americans, Asians/Pacific Islanders, Hispanics, and Native Americans. The percent of serologically defined B45‐positive individuals in the 5 populations ranged from 0.7–9.0%. Thirty‐two B45‐positive individuals were randomly chosen, when available, for sequence‐based typing from each ethnic group from a database of 82,979 consecutively typed unrelated individuals. The B*5002 allele was most prevalent in Hispanic (22%) and Caucasian (9%) individuals, while conspicuously absent in African Americans. In addition, a new allele associated with the B45 antigenic specificity, B*4502, has been identified from an African American individual of Middle Eastern descent. In light of the continuing need to reconcile differences between relationships determined by the sequence homologies among alleles and relationships based on the serologic determinants carried by allelic products when determining the level of HLA match for hematopoietic stem cell transplantation, it is suggested that B*5002 be recognized individually from other B*50 alleles when reporting HLA‐B typings for clinical purposes.
Definition of peptide binding motifs amongst the HLA‐A*30 allelic group
Authors: Krausa P. , Münz C. , Keilholz W. , Stevanovic S. , Jones E.Y. , Browning M. , Bunce M. , Rammensee H.‐G. , McMichael A. 
Published: March 2003

Abstract:HLA class I molecules present endogenously processed peptide ligands for surveillance by the T‐cell receptor. This potentially immunogenic surface of HLA and peptide is a consequence of the polymorphism found within the HLA molecule and its preference for ligand binding together with peptide conformation within the binding groove. To investigate the relation between the polymorphic differences between some closely related HLA alleles and their effect on peptide preference, transfectants were established, each containing one of four allelic variants of HLA‐A*30. Peptides from all four transfectants were eluted, and both individual ligands and peptide pools were sequenced. The data shows two distinct peptide motifs which distinguish A*3001 from the other three known A*30 variants. Differences in preferences at minor positions within the peptide sequence were noted between A*3002, A*3003 and A*3004, providing additional evidence of the implications of sequence polymorphism to HLA function.
Molecular, serological and genetic studies on two new HLA‐DRB1 alleles – HLA‐DRB1*0704 and HLA‐DRB1*1507
Authors: Darke C. , Guttridge M.G. , Street J. , Thompson J. , Thomas M. 
Published: March 2003

Acknowledgments:We thank ROS and LJM for their help and interest in this work and Dr Helen Bass, from our laboratory, for the production of EBV‐transformed B‐cell lines. The financial support of the British Bone Marrow Donor Appeal is gratefully acknowledged.Abstract:Two new HLA‐DRB1 alleles (DRB1*0704 and DRB1*1507) were detected during routine polymerase chain reaction (PCR)‐based typing of two Caucasoid bone marrow panel donors due to apparent DRB1*“blanks” being associated with unexpected DRB4, DRB5 and DQB1 alleles. HLA‐DRB1*0704 differed from DRB1*0701 by five consecutive nucleotides at positions 217 to 221 of exon 2 encoding two amino acids substitutions of tyrosine to asparagine at codons 77 and valine to tyrosine at codon 78. DRB1*1507 differed from DRB1*1501 by a single nucleotide at position 127 encoding an amino acid substitution of phenylalanine to tyrosine at codon 47. Their specificities were unequivocally assigned by serology as HLA‐DR7 and DR15, respectively, and family and population studies allowed their likely HLA‐A,B,C,DR,DQ and complement (Bf, C4A, C4B) bearing haplotypes to be identified. No further examples were found in 19,113 HLA‐DR,DQ typed donors from the Welsh Bone Marrow Donor Registry indicating that both these alleles have a phenotype frequency of <0.01% and a gene frequency of <0.00003 (Note).
Two new HLA DPB1 alleles identified by sequence‐based typing: DPB1*8201 and DPB1*8301
Authors: Voorter C.E.M. , Tilanus M.G.J. , Van Den Berg‐Loonen E.M. 
Published: March 2003

Abstract:Two new HLA DPB1 alleles were identified by sequence‐based typing and are reported. Both alleles differ from DPB1*0402 by a single nucleotide: DPB1*8201 has a difference at position 359 (codon 91) leading to an amino acid change from arg to his, making this position a new polymorphic site; DPB1*8301 has a difference at position 280 (codon 65) changing the amino acid from ile to phe ( 1).
What are the candidate groups for pharmacotherapeutic intervention to prevent asthma?
Authors: De Longueville M. 
Published: March 2003

Despite the development of many new therapies for the treatment of asthma, the prevalence of this disease is still increasing in many areas of the world. Today no intervention is able to completely cure asthma but chronic therapies could decrease its severity. Moreover, asthma is one of the most common chronic diseases of childhood and its pharmacoeconomic burden is huge. Epidemiologic studies have identified some of the major factors involved in the pathogenesis and evolution of asthma. Several prevention programs have been developed in different countries with various success rates. Most of those interventions were based on allergen avoidance. From studies aimed at controlling early asthma and from epidemiologic data, we have learned to identify high‐risk groups, e.g, the atopic child with allergic asthma, with a family history of asthma or allergy‐related disease and early sensitization to aeroallergens. Only a few prospective studies aimed at preventing the onset of asthma have been published. With ketotifen, Iikura et al. could prevent the onset of asthma after a 1‐year period in patients suffering from atopic dermatitis. Another study has been published by Bustos et al. concerning children with a family history of allergy and high total IgE levels. Those studies involved about 100 patients. No follow‐up data has been published for either of them. Recently, the first results from the ETAC® (Early Treatment of the Atopic Child) trial have been reported. This study involved 817 atopic children with atopic dermatitis and a family history of atopy: cetirizine halved the number of patients developing asthma in the subgroups (200 children) sensitized to house dust mite (51.5% versus 28.6%) or pollen (58.8% versus 27.8%). The optimal target for pharmaceutical intervention to prevent asthma would seem to be high risk patients: children with atopic dermatitis, a family history of asthma or atopic disease and early sensitization to aeroallergens. Primary prevention in whole populations (e.g. starting even before the onset of atopic dermatitis or allergen sensitization) does not at present appear to be a realistic approach.