bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serum acute phase protein concentrations after hysterectomy with and without low‐molecular‐weight heparin thrombosis prophylaxis
Authors: Maciejczyk‐Pencuła Monika , Polak Grzegorz , Kotarski Jan 
Published: July 2005

Background.  Low‐molecular‐weight heparin (LMWH) is recommended for venous thrombosis prophylaxis. There are several lines of evidence that heparins exhibit anti‐inflammatory properties in addition to their anticoagulant activity. Therefore, we decided to estimate the concentrations of C‐reactive protein (CRP) and haptoglobin, as acute‐phase proteins, in the blood serum of patients who underwent total abdominal hysterectomy with and without the LMWH administration.Method.  Forty‐two women were studied, including 26 patients treated with enoxaparin and a group of 16 women without thrombosis prophylaxis. Haptoglobin and CRP concentrations were measured in serum samples obtained before the operation and also 8, 24, 48, 72, 96, and 192 hr after surgery.Results.  Serum CRP level measured 8 hr after the operation was significantly higher in the group without thrombosis prophylaxis, however, no statistically significant differences in the concentration of CRP between studied groups in the other time periods were found. There were no statistically significant differences in serum haptoglobin levels between the groups of patients in all time periods.Conclusion.  Administration of low‐molecular‐weight heparin may affect CRP production, however, further studies are still needed in order to clarify the exact immunosuppressive action of heparins.
Gonadotrophin‐releasing hormone‐antagonist luteolysis during the preceding mid‐luteal phase is a feasible protocol in ovarian hyperstimulation before in vitro fertilization
Authors: Fridén Barbro E. , Nilsson Lars 
Published: July 2005

Background.  The aims of this study were to investigate whether a high dose of gonadotrophin‐releasing hormone antagonist during the preceding luteal phase yields satisfactory luteolysis and downregulation prior to ovarian hyperstimulation in an in vitro fertilization program.Methods.  The treatment protocol was designed as a prospective pilot study in IVF units at two university hospitals. Fifty‐one patients with documented poor or normal response to ovarian stimulation underwent 57 treatment cycles. Treatment consisted of 3 mg gonadotrophin‐releasing hormone antagonist (cetrorelix) given during the preceding mid‐luteal phase as gonadotrophin‐releasing hormone‐receptor inhibition before ovarian stimulation with follicle‐stimulating hormone.Results.  All women experienced menstrual bleeding within 2–3 days after the injection of 3 mg cetrorelix. Follicle hormone stimulation could subsequently commence in all cycles. All but three patients developed growing follicles and underwent oocyte retrieval. Seventy‐five percent of started cycles reached transfer of one or two good‐quality embryos.Conclusions.  A single high‐dose gonadotrophin‐releasing hormone antagonist given during the preceding luteal phase presents a new and feasible protocol to initiate controlled ovarian hyperstimulation in an in vitro fertilization program.
Follicle‐stimulating hormone receptor polymorphisms in a population of infertile women
Authors: Falconer Henrik , Andersson Eva , Aanesen Arthur , Fried Gabriel 
Published: July 2005

Background.  There are two known polymorphisms of clinical relevance in the follicle‐stimulating hormone (FSH) receptor exon 10, alanine or threonine at position 307, and asparagine or serine at position 680, giving rise to two discrete allelic variants: Thr307/Asn680 and Ala307/Ser680. At position 680, three FSH receptor variants are possible: Asn/Asn, Asn/Ser, and Ser/Ser. We hypothesized an association between FSH receptor polymorphisms and ovarian reserve.Methods.  FSH receptor polymorphisms at position 680 were studied in a population of 68 infertile women. We used serum FSH level at cycle day 3 as a screening for ovarian reserve. DNA was extracted from peripheral leukocytes in whole blood by using PCR and DNA sequencing in order to determine the type of FSH receptor.Results.  The distribution of FSH receptor variants was Asn/Asn (AA) 35%, Asn/Ser (AS) 24%, and Ser/Ser (SS) 41%. In women with normal ovarian reserve, FSH levels at cycle day 3 were 5.6 ± 1.9 (AA group), 6.7 ± 1.3 (AS group), and 5.7 ± 1.7 (SS group) (non‐significant). Corresponding FSH levels at cycle day 10 were 6.9 ± 1.9, 6.3 ± 1.7, and 8.3 ± 2.8 (P < 0.01, AA and AS vs. SS group). In the SS group, FSH levels at cycle day 10 were significantly higher than they were at cycle day 3 (P < 0.05).Conclusions.  The results show that Ser/Ser‐680 predominates in the studied infertile population. Furthermore, women with normal ovarian reserve and the Ser/Ser FSH receptor variant had significantly higher FSH levels, compared to women with Asn/Asn and Asn/Ser variants. FSH receptor genotyping may, thus, be interesting as an adjunct indicator of ovarian reserve for infertile women undergoing assisted reproduction, and may be helpful in the determination of the starting dosage of FSH in in vitro fertilization.
Magnetic resonance imaging in 300 cases of placenta accreta: surgical correlation of new findings
Authors: Palacios Jaraquemada José M. , Bruno Claudio H. 
Published: July 2005

Background.  To establish the usefulness of placental magnetic resonance in patients with a diagnosis of placenta accreta through the correlation of diagnostic images and surgical findings.Methods.  Three hundred patients with ultrasound signs of placenta accreta were studied. In 252 patients, magnetic resonance imaging (MRI) was performed in a closed 1.5 T‐resonator, and in 48 patients, open 0.23 T‐set was used. T1 and T2 slices in the three planes were performed, and placental invasion was classified in depth levels and topographic areas in relation to the posterior vesical wall. The final degree of invasion was established during surgery according to clinical and anatomical criteria. The information obtained with MRI was analyzed, thus establishing its relevance to the change in surgical technique.Results.  In 286 cases, MRI provided topographic information of placental invasion, and in 90 patients, it modified invasion levels. Undiagnosed parametrium extent was determined in 11 cases, and 11 other cases were reclassified as placenta previa. Changes in conduct following MRI study included: recommendation to modify surgery date at week 35, recommendation for prophylactic ureteral catheterization, recommendation for the use of intraoperative blood salvage, possibility of approach through Pfannenstiel incision, probability of segmental myometrial approach, probability of aortic clamping, need to investigate subclinical disseminated intravascular coagulation, need of posterior pelvic dissection, and the possibility of uterine conservation.Conclusions.  Magnetic resonance imaging turned out to be essential to define the topography and area of placental invasion. New findings modified surgical tactic and technique, allowing a reduction in historical morbidity and a significant increase in conservative surgeries.
Sample preparation procedures for biological atomic force microscopy
Authors: EL KIRAT K. , BURTON I. , DUPRES V. , DUFRENE Y. F. 
Published: July 2005

SummarySince the late 1980s, atomic force microscopy (AFM) has been increasingly used in biological sciences and it is now established as a versatile tool to address the structure, properties and functions of biological specimens. AFM is unique in that it provides three‐dimensional images of biological structures, including biomolecules, lipid films, 2D protein crystals and cells, under physiological conditions and with unprecedented resolution. A crucial prerequisite for successful, reliable biological AFM is that the samples need to be well attached to a solid substrate using appropriate, nondestructive methods. In this review, we discuss common techniques for immobilizing biological specimens for AFM studies.
Essential Amino Acids of the Hantaan Virus N Protein in Its Interaction with RNA
Authors: Severson William , Xu Xiaolin , Kuhn Michaela , Senutovitch Nina , Thokala Mercy , Ferron François , Longhi Sonia , Canard Bruno , Jonsson Colleen B. 
Published: July 2005

ABSTRACT
The nucleocapsid (N) protein of hantavirus encapsidates viral genomic and antigenomic RNAs. Previously, deletion mapping identified a central, conserved region (amino acids 175 to 217) within the Hantaan virus (HTNV) N protein that interacts with a high affinity with these viral RNAs (vRNAs). To further define the boundaries of the RNA binding domain (RBD), several peptides were synthesized and examined for the ability to bind full-length S-segment vRNA. Peptide 195-217 retained 94% of the vRNA bound by the HTNV N protein, while peptides 175-186 and 205-217 bound only 1% of the vRNA. To further explore which residues were essential for binding vRNA, we performed a comprehensive mutational analysis of the amino acids in the RBD. Single and double Ala substitutions were constructed for 18 amino acids from amino acids 175 to 217 in the full-length N protein. In addition, Ala substitutions were made for the three R residues in peptide 185-217. An analysis of protein-RNA interactions by electrophoretic mobility shift assays implicated E192, Y206, and S217 as important for binding. Chemical modification experiments showed that lysine residues, but not arginine or cysteine residues, contribute to RNA binding, which agreed with bioinformatic predictions. Overall, these data implicate lysine residues dispersed from amino acids 175 to 429 of the protein and three amino acids located in the RBD as essential for RNA binding.
Impaired Virus Control and Severe CD8+T-Cell-Mediated Immunopathology in Chimeric Mice Deficient in Gamma Interferon Receptor Expression on both Parenchymal and Hematopoietic Cells
Authors: Henrichsen Pernille , Bartholdy Christina , Christensen Jan Pravsgaard , Thomsen Allan Randrup 
Published: July 2005

ABSTRACTBone marrow chimeras were used to determine the cellular target(s) for the antiviral activity of gamma interferon (IFN-γ). By transfusing such mice with high numbers of naive virus-specific CD8+T cells, a system was created in which the majority of virus-specific CD8+T cells would be capable of responding to IFN-γ, but expression of the relevant receptor on non-T cells could be experimentally controlled. Only when the IFN-γ receptor is absent on both radioresistant parenchymal and bone marrow-derived cells will chimeric mice challenged with a highly invasive, noncytolytic virus completely lack the ability to control the infection and develop severe wasting disease. Further, the study shows that IFN-γ receptor expression on parenchymal cells in the viscera is more important for virus control than IFN-γ receptor expression on bone marrow-derived cells.
The Severe Acute Respiratory Syndrome Coronavirus 3a Protein Up-Regulates Expression of Fibrinogen in Lung Epithelial Cells
Authors: Tan Yee-Joo , Tham Puay-Yoke , Chan Daphne Z. L. , Chou Chih-Fong , Shen Shuo , Fielding Burtram C. , Tan Timothy H. P. , Lim Seng Gee , Hong Wanjin 
Published: July 2005

ABSTRACTHere we analyzed the gene expression profile of cells that stably express the severe acute respiratory syndrome coronavirus (SARS-CoV) 3a protein to determine its effects on host functions. A lung epithelial cell-line, A549, was chosen for this study because the lung is the primary organ infected by SARS-CoV and fatalities resulted mainly from pulmonary complications. Our results showed that the expression of 3a up-regulates the mRNA levels of all three subunits, Aα, Bβ, and γ, of fibrinogen. Consequently, the intracellular levels as well as the secretion of fibrinogen were increased. We also observed increased fibrinogen levels in SARS-CoV-infected Vero E6 cells.
Inhibition of Transcription and Translation in Sindbis Virus-Infected Cells
Authors: Gorchakov Rodion , Frolova Elena , Frolov Ilya 
Published: July 2005

ABSTRACT
Alphaviruses are arthropod-borne viruses (arboviruses) that include a number of important human and animal pathogens. The natural transmission cycle of alphaviruses requires their presence at high concentrations in the blood of amplification hosts for efficient infection of mosquito vectors. The high-titer viremia development implies multiple rounds of infection that proceed in the background of the developing antiviral cell response aimed at blocking virus spread on an organismal level. Therefore, as for many viruses, if not most of them, alphaviruses have evolved mechanisms directed toward downregulating different components of the antiviral cell reaction and increasing viremia to a level sufficient for the next round of transmission. Using Sindbis virus (SIN) as a model, we demonstrated that (i) the replication of wild-type SIN strongly affects major cellular processes, e.g., transcription and translation of mRNAs; (ii) transcriptional and translational shutoffs are distinctly independent events, and their development can be differentially manipulated by creating different mutations in SIN nonstructural protein nsP2; and (iii) inhibition of transcription, but not translation, is a critical mechanism that SIN employs to suppress the expression of cellular viral stress-inducible genes in cells of vertebrate origin. Downregulation of transcription of all of the cellular mRNAs appears to be a very efficient means of reducing the development of an antiviral response. The ability to cause transcriptional shutoff may partially determine SIN host range and replication in particular tissues.
An Envelope-Determined, pH-Independent Endocytic Route of Viral Entry Determines the Susceptibility of Human Immunodeficiency Virus Type 1 (HIV-1) and HIV-2 to Lv2 Restriction
Authors: Marchant David , Neil Stuart J. D. , Aubin Keith , Schmitz Christian , McKnight Áine 
Published: July 2005

ABSTRACT
We identified a postentry restriction, termed Lv2, which determines the cellular tropism of two related human immunodeficiency virus type 2 (HIV-2) isolates and is dependent on the sequence of the capsid (CA) and envelope (Env) proteins. To explain the reliance on both CA and Env, we proposed that restrictive Envs deliver susceptible capsids to a compartment where Lv2 is active whereas nonrestrictive Envs deliver capsids into a compartment where Lv2 is either absent or less active. To test this model, we used compounds that affect endocytic pathways (ammonium chloride, bafilomycin A1, hypertonic sucrose) or lipid rafts (methyl-β-cyclodextrin) to treat restrictive cells and show that restricted virus can be rescued from Lv2 if a lipid-raft-dependent, pH-independent endocytic pathway is inhibited. Furthermore, viral entry into HeLa/CD4 cells containing a tailless CD4 receptor, located outside lipid rafts, was fully permissive. Finally, we show that a variety of primary HIV-1 and HIV-2 viruses are susceptible to Lv2. Thus, we show that the route of entry, determined by the viral envelope, can influence cellular tropism by avoiding intracellular blocks to infection.
Role of B-Cell Proliferation in the Establishment of Gammaherpesvirus Latency
Authors: Moser Janice M. , Upton Jason W. , Allen Robert D. , Wilson Christopher B. , Speck Samuel H. 
Published: July 2005

ABSTRACT

Murine gammaherpesvirus 68 (γHV68) provides a tractable small animal model with which to study the mechanisms involved in the establishment and maintenance of latency by gammaherpesviruses. Similar to the human gammaherpesvirus Epstein-Barr virus (EBV), γHV68 establishes and maintains latency in the memory B-cell compartment following intranasal infection. Here we have sought to determine whether, like EBV infection, γHV68 infection in vivo is associated with B-cell proliferation during the establishment of chronic infection. We show that γHV68 infection leads to significant splenic B-cell proliferation as late as day 42 postinfection. Notably, γHV68 latency was found predominantly in the proliferating B-cell population in the spleen on both days 16 and 42 postinfection. Furthermore, virus reactivation upon ex vivo culture was heavily biased toward the proliferating B-cell population. DNA methyltransferase 1 (Dnmt1) is a critical maintenance methyltransferase which, during DNA replication, maintains the DNA methylation patterns of the cellular genome, a process that is essential for the survival of proliferating cells. To assess whether the establishment of γHV68 latency requires B-cell proliferation, we characterized infections of conditional Dnmt1 knockout mice by utilizing a recombinant γHV68 that expresses Cre-recombinase (γHV68-Cre). In C57BL/6 mice, the γHV68-Cre virus exhibited normal acute virus replication in the lungs as well as normal establishment and reactivation from latency. Furthermore, the γHV68-Cre virus also replicated normally during the acute phase of infection in the lungs of Dnmt1 conditional mice. However, deletion of the
Dnmt1
alleles from γHV68-infected cells in vivo led to a severe ablation of viral latency, as assessed on both days 16 and 42 postinfection. Thus, the studies provide direct evidence that the proliferation of latently infected B cells is critical for the establishment of chronic γHV68 infection.
Frequent Coinfection of Cells Explains Functional In Vivo Complementation between Cytomegalovirus Variants in the Multiply Infected Host
Authors: Čičin-Šain Luka , Podlech Jürgen , Messerle Martin , Reddehase Matthias J. , Koszinowski Ulrich H. 
Published: July 2005

ABSTRACT

In contrast to many other virus infections, primary cytomegalovirus (CMV) infection does not fully protect against reinfection. Accordingly, clinical data have revealed a coexistence of multiple human CMV variants/strains in individual patients. Notably, the phenomenon of multiple infection was found to correlate with increased virus load and severity of CMV disease. Although of obvious medical relevance, the mechanism underlying this correlation is unknown. A weak immune response in an individual could be responsible for a more severe disease and for multiple infections. Alternatively, synergistic contributions of variants that differ in their biological properties can lead to qualitative changes in viral fitness by direct interactions such as genetic recombination or functional complementation within coinfected host cells. We have addressed this important question paradigmatically with the murine model by differently designed combinations of two viruses employed for experimental coinfection of mice. Specifically, a murine cytomegalovirus (MCMV) mutant expressing Cre recombinase was combined for coinfection with a mutant carrying Cre-inducible green fluorescent protein gene, and attenuated mutants were combined for coinfection with wild-type virus followed by two-color in situ hybridization studies visualizing the replication of the two viruses in infected host organs. These different approaches concurred in the conclusion that coinfection of host cells is more frequent than statistically predicted and that this coinfection alters virus fitness by functional
trans
-complementation rather than by genetic recombination. The reported findings make a major contribution to our molecular understanding of enhanced CMV pathogenicity in the multiply infected host.
The Long Terminal Repeat-Containing Retrotransposon Tf1 Possesses Amino Acids in Gag That Regulate Nuclear Localization and Particle Formation
Authors: Kim Min-Kyung , Claiborn Kathryn C. , Levin Henry L. 
Published: July 2005

ABSTRACT

Tf1 is a long terminal repeat-containing retrotransposon of
Schizosaccharomyces pombe
that is studied to further our understanding of retrovirus propagation. One important application is to examine Tf1 as a model for how human immunodeficiency virus type 1 proteins enter the nucleus. The accumulation of Tf1 Gag in the nucleus requires an N-terminal nuclear localization signal (NLS) and the nuclear pore factor Nup124p. Here, we report that NLS activity is regulated by adjacent residues. Five mutant transposons were made, each with sequential tracts of four amino acids in Gag replaced by alanines. All five versions of Tf1 transposed with frequencies that were significantly lower than that of the wild type. Although all five made normal amounts of Gag, two of the mutations did not make cDNA, indicating that Gag contributed to reverse transcription. The localization of the Gag in the nucleus was significantly reduced by mutations A1, A2, and A3. These results identified residues in Gag that contribute to the function of the NLS. The Gags of A4 and A5 localized within the nucleus but exhibited severe defects in the formation of virus-like particles. Of particular interest was that the mutations in Gag-A4 and Gag-A5 caused their nuclear localization to become independent of Nup124p. These results suggested that Nup124p was only required for import of Tf1 Gag because of its extensive multimerization.
Utilization of Homotypic and Heterotypic Proteins of Vesicular Stomatitis Virus by Defective Interfering Particle Genomes for RNA Replication and Virion Assembly: Implications for the Mechanism of Homologous Viral Interference
Authors: Kim Gyoung Nyoun , Kang C. Yong 
Published: July 2005

ABSTRACT

Defective interfering (DI) particles of Indiana serotype of vesicular stomatitis virus (VSV
Ind
) are capable of interfering with the replication of both homotypic VSV
Ind
and heterotypic New Jersey serotype (VSV
NJ
) standard virus. In contrast, DI particles from VSV
NJ
do not interfere with the replication of VSV
Ind
standard virus but do interfere with VSV
NJ
replication. The differences in the interfering activities of VSV
Ind
DI particles and VSV
NJ
DI particles against heterotypic standard virus were investigated. We examined the utilization of homotypic and heterotypic VSV proteins by DI particle genomic RNAs for replication and maturation into infectious DI particles. Here we show that the RNA-nucleocapsid protein (N) complex of one serotype does not utilize the polymerase complex (P and L) of the other serotype for RNA synthesis, while DI particle genomic RNAs of both serotypes can utilize the N, P, and L proteins of either serotype without serotypic restriction but with differing efficiencies as long as all three proteins are derived from the same serotype. The genomic RNAs of VSV
Ind
DI particles assembled and matured into DI particles by using either homotypic or heterotypic viral proteins. In contrast, VSV
NJ
DI particles could assemble only with homotypic VSV
NJ
viral proteins, although the genomic RNAs of VSV
NJ
DI particles could be replicated by using heterotypic VSV
Ind
N, P, and L proteins. Thus, we concluded that both efficient RNA replication and assembly of DI particles are required for the heterotypic interference by VSV DI particles.
Two Sp1/Sp3 Binding Sites in the Major Immediate-Early Proximal Enhancer of Human Cytomegalovirus Have a Significant Role in Viral Replication
Authors: Isomura Hiroki , Stinski Mark F. , Kudoh Ayumi , Daikoku Tohru , Shirata Noriko , Tsurumi Tatsuya 
Published: July 2005

ABSTRACT

We previously demonstrated that the major immediate early (MIE) proximal enhancer containing one GC box and the TATA box containing promoter are minimal elements required for transcription and viral replication in human fibroblast cells (H. Isomura, T. Tsurumi, M. F. Stinski, J. Virol.
78:
12788-12799, 2004). After infection, the level of Sp1 increased while Sp3 remained constant. Here we report that either Sp1 or Sp3 transcription factors bind to the GC boxes located at approximately positions −55 and −75 relative to the transcription start site (+1). Both the Sp1 and Sp3 binding sites have a positive and synergistic effect on the human cytomegalovirus (HCMV) major immediate-early (MIE) promoter. There was little to no change in MIE transcription or viral replication for recombinant viruses with one or the other Sp1 or Sp3 binding site mutated. In contrast, mutation of both the Sp1 and Sp3 binding sites caused inefficient MIE transcription and viral replication. These data indicate that the Sp1 and Sp3 binding sites have a significant role in HCMV replication in human fibroblast cells.