bluuebunny/crossref_metadata_2025 huggingface dataset:
Antimicrobial activity and tightness of a DCPD–CaO‐based hydraulic calcium phosphate cement for root canal filling
Authors: Michaïlesco Pierre , Kouassi Michel , El Briak Hasna , Armynot Anne , Boudeville Philippe
Published: June 2005

Calcium hydroxide is currently used in dentistry for endodontic treatments where its main advantage is its antibacterial and anti‐inflammatory activity. However, it also has some drawbacks such as pulp necrosis, slight solubility, slow and insufficient hardening, and retraction on drying. In consequence, it is used only as temporary material for root canal disinfection. By mixing calcium hydrogen phosphate dihydrate (CaHPO4 · 2H2O, also called dicalcium phosphate dihydrate, DCPD) and calcium oxide with a sodium phosphate buffer as liquid phase, we obtained a CPC with better mechanical properties than calcium hydroxide pastes. The setting reaction produced either hydroxyapatite (HA) or a mixture of HA and calcium hydroxide depending on the relative masses of DCPD and CaO in the cement powder. The presence of calcium hydroxide a priori confers antimicrobial properties to this cement which were investigated in agar plates (diffusion method) against Streptococcus mutans, Lactobacillus acidophilus, Candida albicans, Enterococcus faecalis, Staphylococcus hominis (clinical isolates), and a preparation of polymicrobial flora isolated from dental plaque. The cement samples tested were prepared at molar calcium‐to‐phosphate ratios (Ca/P) of 1.67 to 2.75. A pure calcium hydroxide paste was used as reference material. Clear and reproducible bacterial growth inhibition was observed for cement samples with Ca/P ≥ 2 against all the microorganisms tested. With Ca/P = 2.5, this cement alkalinizes dentinal tubules and provides a fluid‐tight sealing that well compares with sealing obtained using a zinc oxide–eugenol cement without gutta‐percha point. DCPD–CaO‐based cement is therefore a potential root canal filler. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
The contradictory effects of pores on fatigue cracking of bone cement
Authors: Janssen Dennis , Aquarius René , Stolk Jan , Verdonschot Nico
Published: June 2005

The beneficial effect of porosity reduction on the fatigue life of bone cement has been demonstrated in numerous experimental studies. Clinically, however, it seems that the beneficial effect of porosity reduction of cement around total hip replacement components can only be found in large follow‐up studies. Little is known about the actual mechanical effect of a pore on fatigue crack formation in cement mantles. We studied the effect of pores on the crack formation process in a finite element model of a transverse slice of a total hip reconstruction. We created models with a single large pore and models with multiple pores at levels of 2, 4, and 9%. The models were cyclically torque‐loaded, causing macrocracks to appear in the cement mantle. In all models, we found that pores acted as microcrack initiators. However, pores could have both a detrimental and a beneficial effect on the macrocrack propagation in the cement mantle. Both effects were seen in the models with a single large pore and in the models with multiple pores. Pores would either accelerate, deviate, or decelerate the macrocrack propagation in the cement mantle. The effect of the pores depended on the location of the pores with respect to the stress intensities in the model, but was independent of the pore size or the level of porosity. The results may explain why the beneficial effect of vacuum mixing is difficult to demonstrate clinically. Stress intensities that are present in a cement mantle in an in vivo situation may overshadow the detrimental effect of a pore, while the beneficial effect may become more pronounced. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Three‐dimensional printing of porous ceramic scaffolds for bone tissue engineering
Authors: Seitz Hermann , Rieder Wolfgang , Irsen Stephan , Leukers Barbara , Tille Carsten
Published: June 2005

This article reports a new process chain for custom‐made three‐dimensional (3D) porous ceramic scaffolds for bone replacement with fully interconnected channel network for the repair of osseous defects from trauma or disease. Rapid prototyping and especially 3D printing is well suited to generate complex‐shaped porous ceramic matrices directly from powder materials. Anatomical information obtained from a patient can be used to design the implant for a target defect. In the 3D printing technique, a box filled with ceramic powder is printed with a polymer‐based binder solution layer by layer. Powder is bonded in wetted regions. Unglued powder can be removed and a ceramic green body remains. We use a modified hydroxyapatite (HA) powder for the fabrication of 3D printed scaffolds due to the safety of HA as biocompatible implantable material and efficacy for bone regeneration. The printed ceramic green bodies are consolidated at a temperature of 1250°C in a high temperature furnace in ambient air. The polymeric binder is pyrolysed during sintering. The resulting scaffolds can be used in tissue engineering of bone implants using patient‐derived cells that are seeded onto the scaffolds.This article describes the process chain, beginning from data preparation to 3D printing tests and finally sintering of the scaffold. Prototypes were successfully manufactured and characterized. It was demonstrated that it is possible to manufacture parts with inner channels with a dimension down to 450 μm and wall structures with a thickness down to 330 μm. The mechanical strength of dense test parts is up to 22 MPa. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
The role of graft materials in suture augmentation for tendon repairs and reattachment
Authors: Kummer Frederick J. , Iesaka Kazuho
Published: June 2005

Various biomaterials have been used to augment sutures for the repair and reattachment of tendons. This study examined four different graft materials in a simple and reproducible model using chicken Achilles tendons to determine the strength and mechanism of suture reinforcement of tendon repairs. The graft materials tested were Gore‐Tex® Soft Tissue Patch, Graftjacket™, bovine pericardium, and an experimental graft material from Xylos Corporation. Testing was performed in shear to simulate forces on a torn tendon repair and pull‐off to simulate those on a tendon reattachment to bone. Compared to unaugmented suture, grafts increased suture fixation strength from 10% to 60% in shear and from 0% to 36% in pull‐off with the bovine pericardium graft, providing significant improvement in both tests. In no cases (even unaugmented) did the suture pull directly through the tendon, but instead sliced along it, demonstrating that the interface between the suture and the tendon determines fixation strength. Grafts function by increasing the area, friction, and nature of this interface, not by acting as a barrier for suture pull‐through. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Three‐dimensional tomography of composite fracture surfaces
Authors: Drummond James L. , De Carlo Francesco , Super Boaz J.
Published: June 2005

The goal of this project was to image the three‐dimensional fracture interface of a dental composite with the use of X‐ray tomography. With the use of the Advanced Photon Source (APS) at Argonne National Laboratory, three‐dimensional images were obtained of the crack interface of a dental composite material that had been subjected to three different treatments: a control, cycled in air, and cycled in a 50/50 mixture by volume of ethanol and distilled water. The cycle‐loaded treatments were for 100,000 cycles at a load between 80 and 100 N at 5 Hz. The crack interface extended over 28 slices for the control, 96 for the air‐cycled specimen, and 83 slices for the 50/50 solution cycle specimen. It would appear that the fatiguing of the specimens allowed for an increase in the crack interface as demonstrated by the 3D tomographical analysis. This volume increase in the crack interface is attributed to a separation of the filler fiber from the resin matrix. Three‐dimensional tomography provides an excellent method to observe crack interfaces of dental composites subjected to different types of mechanical and environmental conditions. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Histology and ultrastructure of a tissue‐engineered collagen meniscus before and after implantation
Authors: Reguzzoni Marcella , Manelli Alessandro , Ronga Mario , Raspanti Mario , Grassi Federico A.
Published: June 2005

The collagen meniscus implant (CMI) is a tissue‐engineering technique designed to stimulate regeneration of meniscus‐like tissue in cases of irreparable tears or previous meniscectomy. CMI morphology was investigated before and after implantation by light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). In a case series biopsy specimens were harvested from four patients who underwent a second arthroscopic look 6 months after placement of the CMI. CMI sections appeared composed of parallel connective laminae of 10–30 μm, connected by smaller bundles (5–10 μm). This connective network formed lacunae with diameters between 40 and 60 μm. At greater magnification, the walls of the lacunae demonstrated tightly packed and randomly distributed collagen fibrils, with diameters ranging from 73 to 439 nm. In the biopsy specimens, the lacunae were filled with connective tissue that contained newly formed vessels and fibroblast‐like cells, presenting an abundant rough endoplasmic reticulum and several mitochondria. In the extracellular matrix, the collagen fibrils showed uniform diameters (126 nm ± 32 nm). The original structure of CMI was still recognizable, and no inflammatory cells were detected within the implant. The morphological findings of this case series demonstrate that CMI provides a three‐dimensional scaffold suitable for colonization by precursor cells and vessels and leading to the formation of a fully functional tissue. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
The preparation and characteristics of a carbonated hydroxyapatite/collagen composite at room temperature
Authors: Liao Susan , Watari Fumio , Uo Motohiro , Ohkawa Shoji , Tamura Kazuchika , Wang Wei , Cui Fuzhai
Published: June 2005

Nanocarbonated hydroxyapatite/collagen (nCHAC) composite was prepared at room temperature via biomimetic self‐assembly method. X‐ray diffraction (XRD), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) were performed. This composite shows the same inorganic phase of natural bone with nanosized level and low degree of crystallinity, and contains 2.8–14.7 wt % of carbonated content. TEM results confirm that the microstructure of this composite is the mineralized collagen fiber bundle like the hierarchical structure of natural bone. The diameter of a single mineralized collagen fiber is about 4 nm. Slightly different assembly units of the composite with different carbonates and collagen were demonstrated. The carbonated percentage affects the mineral crystal size and collagen fibril assembly. Because of the biomimetic component and microstructure, the use of nCHAC composite is promising for hard tissue therapy. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Energetic and topological analyses of the oxidation reaction between Mon (n = 1, 2) and N2O
Authors: Michelini Maria Del Carmen , Russo Nino , Alikhani Mohammad Esmaïl , Silvi Bernard
Published: June 2005

The interaction between molybdenum, atom, and dimer, with nitrous oxide has been investigated using density functional theory. The analysis of the potential energy surfaces for both reactions has revealed that a single molybdenum atom can activate the NO bond of N2O requiring a small activation energy. However, the presence of several intersystem crossings between three different spin states, namely, septet, quintet and triplet states, seems to be the major constraint to the Mo + N2O reaction. Contrarily, the low‐lying excited states (triplet and quintet) do not participate in the reaction between the molybdenum dimer and N2O. The latter reaction fully evolves on the singlet spin surface. Three different regions have been distinguished along the pathway: formation of an adduct complex, formation of an inserted compound, and the N2 detachment. The connection between the two first regions has been characterized by the formation of a special complex in which the NO bond is so weakened that it could be considered as a first step in the insertion process. It has been shown that the topological changes along the pathways provide a clear explanation for the geometrical changes that occur along the reaction pathway. In summary, the detachment of the N2 molecule is found to be kinetically an effective process for both reactions, owing to the high exothermicity and consequently to the high internal energy of the insertion intermediates. However, in the case of Mo atom, the reaction should be a slow process due to the presence of spin‐forbidden transitions. These results fully agree with previous experimental works. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1284–1293, 2005
Absolute free energies of binding of peptide analogs to the HIV‐1 protease from molecular dynamics simulations
Authors: Bartels Christian , Widmer Armin , Ehrhardt Claus
Published: June 2005

The constants of binding of five peptide analogs to the active site of the HIV‐1 aspartic‐protease are calculated based on a novel sampling scheme that is efficient and does not introduce any approximations in addition to the energy function used to describe the system. The results agree with experiments. The squared correlation coefficient of the calculated vs. the measured values is 0.79. The sampling scheme consists of a series of molecular dynamics integrations with biases. The biases are selected based on an estimate of the probability density function of the system in a way to explore the conformational space and to reduce the statistical error in the calculated binding constants. The molecular dynamics integrations are done with a vacuum potential using a short cutoff scheme. To estimate the probability density of the simulated system, the results of the molecular dynamics integrations are combined using an extension of the weighted histogram analysis method (C. Bartels, Chem. Phys. Letters 331 (2000) 446–454). The probability density of the solvated ligand–protein system is obtained by applying a correction for the use of the short cutoffs in the simulations and by taking into account solvation with an electrostatic term and a hydrophobic term. The electrostatic part of the solvation is determined by finite difference Poisson–Boltzmann calculations; the hydrophobic part of the solvation is set proportional to the solvent accessible surface area. Setting the hydrophobic surface tension parameter equal to 8 mol−1 K−1 A−2, absolute binding constants are in the μM to nM range. This is in agreement with experiments. The standard errors determined from eight repeated binding constant determinations are a factor of 14 to 411. A single determination of a binding constant is done with 499700 steps of molecular dynamics integration and 4500 finite difference Poisson–Boltzmann calculations. The simulations can be analyzed with respect to conformational changes of the active site of the HIV‐1 protease or the ligands upon binding and provide information that complements experiments and can be used in the drug development process. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1294–1305, 2005
Coloring 4‐cycle systems
Authors: Burgess Andrea C. , Pike David A.
Published: June 2005

An m‐cycle system of order n is a partition of the edges of the complete graph Kn into m‐cycles. We investigate k‐colorings of 4‐cycle systems in which no 4‐cycle is monochromatic. For any k ≥ 3, we construct a k‐chromatic 4‐cycle system. We also show that for any k ge; 2, there exists an integer wk such that for all admissible n ≥ wk, there is a k‐chromatic 4‐cycle system of order n. © 2005 Wiley Periodicals, Inc. J Combin Designs
Products of mixed covering arrays of strength two
Authors: Colbourn Charles J. , Martirosyan Sosina S. , Mullen Gary L. , Shasha Dennis , Sherwood George B. , Yucas Joseph L.
Published: June 2005

Acovering arrayCA(N;t,k,vis anN × karray such that everyN × tsubarray contains allt‐tuples fromvsymbolsat leastonce, wheretis thestrengthof the array. Covering arrays are used to generate software test suites to cover allt‐sets of component interactions. The particular case whent = 2 (pairwise coverage) has been extensively studied, both to develop combinatorial constructions and to provide effective algorithmic search techniques. In this paper, a simple “cut‐and‐paste” construction is extended to covering arrays in which different columns (factors) admit different numbers of symbols (values); in the process an improved recursive construction for covering arrays witht = 2 is derived. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 124–138, 2006
Decomposition of complete graphs into 5‐cubes
Authors: Bryant D. , El‐Zanati S. I. , Maenhaut B. , Vanden Eynden C.
Published: June 2005

Necessary conditions for the complete graph on n vertices to have a decomposition into 5‐cubes are that 5 divides n − 1 and 80 divides n(n − 1)/2. These are known to be sufficient when n is odd. We prove them also sufficient for n even, thus completing the spectrum problem for the 5‐cube and lending further weight to a long‐standing conjecture of Kotzig. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 159–166, 2006
Irreducible 2‐fold cycle systems
Authors: Jenkins Peter
Published: June 2005

In this paper, it is shown that for any pair of integers (m,n) with 4 ≤ m ≤ n, if there exists an m‐cycle system of order n, then there exists an irreducible 2‐fold m‐cycle system of order n, except when (m,n) = (5,5). A similar result has already been established for the case of 3‐cycles. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 324–332, 2006
Recurrent mutations associated with isolation and passage of SARS coronavirus in cells from non‐human primates
Authors: Poon Leo L.M. , Leung Cynthia S.W. , Chan Kwok H. , Yuen Kwok Y. , Guan Yi , Peiris Joseph S.M.
Published: June 2005

Four clinical isolates of SARS coronavirus were serially passaged in two primate cell lines (FRhK4 and Vero E6). Viral genetic sequences encoding for structural proteins and open reading frames 6–8 were determined in the original clinical specimen, the initial virus isolate (passage 0) and at passages 5, 10, and 15. After 15 passages, a total of 15 different mutations were identified and 12 of them were non‐synonymous mutations. Seven of these mutations were recurrent mutation and all located at the spike, membrane, and Orf 8a protein encoding sequences. Mutations in the membrane protein and a deletion in ORF 6–8 were already observed in passage 0, suggesting these amino acid substitutions are important in the adaptation of the virus isolate in primate cell culture. A mutation in the spike gene (residue 24079) appeared to be unique to adaptation in FRhK4 cells. It is important to be aware of cell culture associated mutations when interpreting data on molecular evolution of SARS coronavirus. J. Med. Virol. 76:435–440, 2005. © 2005 Wiley‐Liss, Inc.
Prevalence of complete resistance to at least two classes of antiretroviral drugs in treated HIV‐1‐infected patients: A French nationwide study
Authors: Masquelier Bernard , Costagliola Dominique , Schmuck Anne , Cottalorda Jacqueline , Schneider Véronique , Izopet Jacques , Calvez Vincent , Descamps Diane , Poggi Cécile , Brun‐Vézinet Françoise ,   the ANRS resistance study group
Published: June 2005

The objective of the study was to estimate the prevalence of HIV‐1 resistance to all drugs belonging to two or more antiretroviral drug (ARV) classes in treated patients in France. All genotyping assays performed in June 2001 and in November 2002 by the ANRS resistance laboratory network were analyzed by the ANRS algorithm. The 17 and 21 centers of the ANRS network participating in the study in 2001 and 2002, respectively, genotyped the viruses in plasma of 456 and 529 patients, respectively. In 2002, the proportions of patients harboring viruses fully resistant to one, two, and three ARV classes were 5.1%, 8.1%, and 2.5%, respectively. These results were similar to those obtained in 2001. In 2002, among the 56 patients with viruses completely resistant to at least two ARV classes, 98%, 96%, and 29% of patients had viruses with complete class resistance to NRTIs, NNRTIs, and PIs, respectively. Complete resistance to PIs was less frequent than full resistance to the other two ARV classes, and ritonavir‐boosted amprenavir and lopinavir/r remained potentially active in respectively 71.4% and 42.9% of these 56 patients. In 2001 and 2002, respectively 30% of the 65 patients and 24% of the 56 patients with viruses completely resistant to at least two ARV classes were at an advanced stage of HIV disease, with CD4+ cell counts below 200/μl and viral loads above 30 000 copies/ml. In France, the prevalence of HIV‐1 viruses completely resistant to two or more ARV classes remained stable between 2001 and 2002. Resistance to RT inhibitors was more frequent than resistance to PIs in patients with viruses completely resistant to two or three classes of ARV. J. Med. Virol. 76:441–446, 2005. © 2005 Wiley‐Liss, Inc.
Diverse pattern of protease inhibitor resistance mutations in HIV‐1 infected patients failing nelfinavir
Authors: Svedhem Veronica , Lindkvist A. , Bergroth T. , Knut Lidman , Sönnerborg A.
Published: June 2005

The aim of the study was to describe the pattern of resistance mutations in human immunodeficiency virus type 1 (HIV‐1) infected patients experiencing their first protease inhibitor (PI) failure on nelfinavir (NFV)‐containing therapy. Earlier PI‐naïve patients (n = 172) with NFV‐containing therapy were therefore retrospectively studied. Plasma HIV RNA from 43 failing patients was sequenced. In addition, virus from the baseline was sequenced in 29 patients. Failure was defined as two consecutive measurements of viral load of >50 copies/ml after 6 months treatment. Subtyping was done in most patients (n = 118). At baseline, the V82A mutation was found in four PI‐naïve patients of whom two failed therapy exhibiting this mutation. At therapy failure, 17 of the 43 (40%) patients had primary PI mutations. In nine subjects, RTI‐mutations only were found and 17 patients had a wild‐type virus. Patients with primary PI and/or RTI mutations had a higher viral load at failure than those who failed with wild‐type virus. A surprisingly diverse pattern of primary PI mutations was seen: M46I (n = 7), D30N (n = 6), L90M (n = 5), and V82A (n = 4). Four patients exhibited more than one primary PI mutation. PI‐naïve patients in Sweden may harbor PI‐resistant virus and resistance testing should be considered before treatment. Patients who fail NFV may develop the M46I mutation, which has been related earlier to mainly other PI. The diverse pattern of the evolved PI‐mutations and the relative low occurrence of the D30N mutation in the material was unexpected and did not seem to be related to the viral subtype. J. Med. Virol. 76:447–451, 2005. © 2005 Wiley‐Liss, Inc.
Subtype analysis and mutations to antiviral drugs in HIV‐1‐infected patients from Mozambique before initiation of antiretroviral therapy: Results from the DREAM programme
Authors: Bellocchi Maria Concetta , Forbici Federica , Palombi Leonardo , Gori Caterina , Coelho Elisabeth , Svicher Valentina , D'Arrigo Roberta , Emberti‐Gialloreti Leonardo , Ceffa Susanna , Erba Fulvio , Marazzi Maria Cristina , Silberstein Francesca Ceccherini , Perno Carlo‐Federico
Published: June 2005

Phylogenetic analysis and evaluation of drug‐resistance were carried out upon 59 plasma samples from 58 treatment‐naïve HIV‐1 infected patients from Mozambique, enrolled in a free antiviral‐therapy protocol in the frame of Drug‐Resource‐Enhancement against AIDS and Malnutrition (DREAM) programme. Sequencing of the first 1,300 bases of the pol‐gene shows that all virus strains cluster within clade C, with the exception of a single patient carrying a G‐subtype virus. Relevant mutations in the reverse transcriptase (RT) are rare: 118A/I/L/G (four patients), 179E/D/I (three patients), 333E/D (two patients), 101R, and 210F (one patient each). In Protease (PR), V82I (10.3%) is the only relevant mutation, while natural polymorphisms/secondary mutations are found, some at very high frequency: 20R (25.9%), 36I (91.4%), 36L (8.6%), 60E (31.0%), 63P (29.3%), and 93L (96.6%). Among them, mutations with a frequency >25% were further investigated to assess their covariation pattern with PI resistance associated mutations. The pattern of covariation observed for K20R and D60E (but not L63P and M36I) was different between C and B subtype isolates from PR‐inhibitor‐treated patients. The sequences were also analyzed to calculate the ratio of non‐synonymous to synonymous substitution. The ratio for PR and RT was 0.116 and 0.093, respectively, suggesting a greater conservation in RT than PR in both subtypes B and C HIV strains. Taken together, the results demonstrate a consistent clade‐homogeneity of viral strains circulating in Mozambique, and the very limited presence, in drug‐naïve patients, of mutations associated with resistance to RT‐inhibitors. The high frequency of secondary mutations/polymorphisms in HIV‐PR deserves further studies to evaluate its relevance in clinical settings. J. Med. Virol. 76:452–458, 2005. © 2005 Wiley‐Liss, Inc.
Purification and partial characterization of R5, R5X4, and X4 HIV‐1 subtype C envelope glycoproteins expressed in insect cells
Authors: Nkosi Sibusiso P. , Huismans Henk , Papathanasopoulos Maria A.
Published: June 2005

Biological properties of four recombinant HIV‐1 subtype C envelope glycoproteins from viruses with different phenotypic characteristics (CCR5 and/or CXCR4‐utilizing) were investigated. The gp160 genes were cloned, expressed in Spodoptera frugiperda insect cells, purified, and their biological characteristics were examined. The conformational and functional integrity of the HIV‐1 subtype C rgp160 was intact since they reacted with the A32, C11, IgG1b12, 7B2, and 17b conformational dependant monoclonal antibodies (MAb), sCD4, and patient sera. Baculovirus derived rgp160 can be used for further structural, functional, antigenic, and immunological studies. J. Med. Virol. 76:459–463, 2005. © 2005 Wiley‐Liss, Inc.
Development of a sensitive assay for the measurement of antibodies against heat shock protein binding protein 1 (HspBP1): Increased levels of anti‐HspBP1 IgG are prevalent in HIV infected subjects
Authors: Papp Diana , Prohászka Zoltán , Kocsis Judit , Füst George , Bánhegyi Dénes , Raynes Deborah A. , Guerriero Vince
Published: June 2005

The 70 kDa heat shock protein (Hsp70) is generally considered to be an intracellular protein, however, there is evidence that Hsp70 can be found in the extracellular environment. Hsp70 and antibodies against Hsp70 have been reported in human serum. Recent evidence has shown that Hsp70 antibodies are elevated in HIV infected individuals. This study reports on the antibody levels against a co‐chaperone, HspBP1, that regulates Hsp70 activity. We have developed a solid‐phase enzyme linked assay for the determination of anti‐HspBP1 IgG antibodies. We report here that HspBP1 antibodies are present in human serum and the levels are elevated approximately twofold in HIV infected patients. There was no correlation between HspBP1 antibody levels and clinical parameters nor was there a relation between anti‐Hsp70 levels and anti‐HspBP1 levels. The presence of HspBP1 antibodies in human serum suggests that the protein may also be present in the serum. The increased level of HspBP1 antibodies in HIV infected individuals suggests a relationship directly to the virus or indirectly to secondary consequences of HIV infection. J. Med. Virol. 76:464–469, 2005. © 2005 Wiley‐Liss, Inc.
Cervical squamous intra‐epithelial changes and human papillomavirus infection in women infected with human immunodeficiency virus in Pune, India
Authors: Joshi Smita N. , Gopalkrishna V. , Kumar B. Kishore , Dutta Soma , Nyaynirgune Pratima , Thakar Madhuri , Tripathy Srikanth , Mehendale Sanjay , Paranjape Ramesh
Published: June 2005

In view of the dual burden of HIV infection and cervical cancers in India, this study was undertaken to estimate the prevalence of Pap smear abnormalities and human papillomavirus infection among HIV‐infected women. Consecutive HIV‐infected women attending voluntary counseling testing clinics were enrolled. Written informed consent, demographic information, Pap smears, cervical swabs for HPV typing and a blood sample for CD4+ cell count were collected. Treatment for opportunistic and sexually transmitted infections and reproductive tract infections was provided. Women with Pap smear abnormality were referred for further intervention. Between January 2003 and May 2004, 287 HIV‐infected women were enrolled. Pap smear abnormalities were seen in 6.3% women and were more common among women aged 30 and above (P = 0.042) and those who had suffered from opportunistic infections (P = 0.004). In multivariate analysis, Pap smear abnormalities were associated independently with opportunistic infections (P = 0.02, AOR 3.8, 95% CI 1.2–11.5). Of the 100 random cervical specimens screened for HPV 16 and 18 genotypes, 33% (95 CI 23.9–43.1) were positive for HPV 16/18. Of the 122 patients who returned for a follow‐up visit, 5 patients (4.1%) who did not have Pap smear abnormality at baseline, had developed Pap smear abnormality. The incidence of Pap smear abnormalities was 5.5 per 100 person year of follow‐up. In order to prevent thousands of deaths due to cervical cancer in India, there is a need for strengthening the Pap smear screening program and HPV vaccine development. J. Med. Virol. 76:470–475, 2005. © 2005 Wiley‐Liss, Inc.
Complete genome sequence and phylogenetic analysis of hepatitis B virus isolated from turkish patients with chronic HBV infection
Authors: Bozdayi Gülendam , Türkyilmaz A. Resat , Idilman Ramazan , Karatayli Ersin , Rota Seyyal , Yurdaydin Cihan , Bozdayi A. Mithat
Published: June 2005

Hepatitis viruses are the leading causes of chronic liver disease resulting in chronic hepatitis, cirrhosis, and hepatocellular carcinoma in the world and also in Turkey. Although Turkey has an intermediate rate of hepatitis B virus (HBV) infection with a prevalence reported as 5%, a complete HBV genome sequence has not been published. In this study, the molecular characterization and phylogenetic analysis are described of 11 complete HBV genomes isolated from 11 naïve patients (5 male, 6 female; ages: 18–54 years old, median 35 years old) with chronic HBV infection. Of 11 patients, 7 and 4 were HBeAg positive/anti‐HBe negative and HBeAg negative/anti‐HBe positive, respectively. All patients had no co‐infection with HCV, HDV, or HIV. HBV DNA was extracted from the sera of the patients. The complete genome was amplified by PCR and cloned into a TA vector. The PCR products were sequenced directly and the complete HBV genome sequences were determined. Ten HBV genomes were 3182 base pairs in length. There was a 183 bp deletion (between nucleotides 2987–3169) in pre‐S region in one HBeAg positive patient. There were two pre‐core stop codons (G1896A) in two HBeAg negative and three core promoter dual mutations (T1762/A1764) in one HBeAg positive and two HBeAg negative patients' HBV genomes. Phylogenetic analysis of all complete genomes yielded that all Turkish sequences were clustered in genotype D branch (ten in subgenotype D1 and one in subgenotype D2). The analysis of S gene amino acid sequences revealed that surface gene subtypes of one and ten HBV strains were subtype ayw3 and ayw2, respectively. This study indicates that Turkish patients with chronic hepatitis B infection show very little genotypic heterogeneity. Genotype D of HBV DNA and subtype ayw2 of surface gene represent almost the whole Turkish patient population infected with HBV. J. Med. Virol. 76:476–481, 2005. © 2005 Wiley‐Liss, Inc.
Intrahepatic cytokine profile in renal‐transplant patients infected by hepatitis C virus
Authors: Kamar Nassim , Rostaing Lionel , Sandres‐Saune Karine , Selves Janick , Barthe Carole , Dubois Martine , Alric Laurent , Durand Dominique , Izopet Jacques
Published: June 2005

In order to examine the immunopathogenesis of hepatitis C virus (HCV)‐related liver injury in renal‐transplant patients, intra‐hepatic cytokine profiles were examined in 38 liver biopsies from 38 patients by measuring messenger RNA (mRNA) concentrations by a real‐time PCR method of a Th1 cytokine (i.e., interferon (IFN)‐γ), a Th2 cytokines (i.e., interleukine (IL)‐10), a proinflammatory cytokine (i.e., IL‐8), and a potent fibrogenic factor (transforming growth factor [TGF]‐β). There was no significant difference in TGF‐β, IFN‐γ, IL‐10, or IL‐8 levels of expression according to liver‐activity grade, liver‐fibrosis stage, the concentration of HCV RNA at liver biopsies, or the HCV genotype. However, IFN‐γ/β‐actin mRNA concentration was higher than the IL‐10/β‐actin mRNA concentration in patients with F3 Metavir score. Median IFN‐γ/β‐actin mRNA concentration tended to be higher in patients with A3 and A4 Metavir activity grades compared with those with A0 and A1 activity grades. There was a significant correlation between the duration of HCV infection and both TGF‐β/β‐actin (r2 = 0.19, P = 0.04) and IL‐8/β‐actin mRNA concentrations (r2 = 0.19, P = 0.03). IFN‐γ/β‐actin mRNA concentration also increased according to the duration of HCV (r2 = 0.19, P = 0.07). Finally, there was a significant correlation between the duration of HCV infection and liver fibrosis stage (r2 = 0.17, P = 0.045). Intrahepatic Th1 cytokine profile seems to be predominant in patients with extensive fibrosis and activity scores, suggesting that it might be responsible for liver injury in renal transplant patients. J. Med. Virol. 76:482–488, 2005. © 2005 Wiley‐Liss, Inc.
Hepatitis C virus‐core and non structural proteins lead to different effects on cellular antioxidant defenses
Authors: Abdalla Maher Y. , Ahmad Iman M. , Spitz Douglas R. , Schmidt Warren N. , Britigan Bradley E.
Published: June 2005

Chronic hepatitis C virus (HCV) infection leads to increased oxidative stress in the liver. Hepatic antioxidant enzymes provide an important line of defense against oxidative injury. To understand the antioxidant responses of hepatocytes to different HCV proteins, we compared changes in antioxidative enzymes in HCV‐core and HCV‐nonstructural protein expressing hepatocyte cell lines. We found that expression of HCV‐core protein in hepatocyte cell lines leads to increased oxidative stress as determined by increased in the oxidant‐sensitive probe 5‐(and‐6)‐chloromethyl‐2′,7′‐dichlorodihydrofluorescein diacetate (CM‐DCFH2) fluorescence, decreased reduced glutathione (GSH), and increased oxidation of thioredoxin (Trx). Although the expression of HCV‐nonstructural (HCV‐NS) proteins led to increased oxidative stress as well, the antioxidant enzymatic responses were different. Over‐expression of HCV‐NS proteins increased antioxidant enzymes (MnSOD and catalase), heme oxygenase‐1 (HO‐1), and GSH, indicating different mechanism(s) of prooxidative activity than HCV‐core protein. Our findings show that different HCV proteins induce different antioxidant defense responses in hepatocytes. These findings may facilitate understanding the interaction of different HCV proteins with infected liver cells and help identify possible factors contributing to hepatocyte damage during HCV infection. J. Med. Virol. 76:489–497, 2005. © 2005 Wiley‐Liss, Inc.
Evolution over a 10 year period of the epidemiological profile of 1,726 newly diagnosed HCV patients in Belgium
Authors: Gérard Christiane , Delwaide Jean , Vaira Dolores , Bastens Boris , Servais Benoît , Wain Etienne , Bataille Christian , Daenen Guy , Belaïche Jacques ,   the GLEVHE
Published: June 2005

In order to evaluate the future burden of hepatitis C, there is a need to quantify the evolution with time of some crucial parameters such as disease frequency and age, modes of infection and infecting genotypes of patients presenting for the first time at consultation. The yearly evolution of these parameters was analyzed retrospectively in a cohort of 1,726 patients living in Belgium, who were diagnosed as hepatitis C virus (HCV) carriers by polymerase chain reaction (PCR) between 1992 and 2002. The epidemiological profile of HCV patients showed significant changes during this period. The number of new patients increased with time. The proportion of patients under 50 increased linearly at a rate of 3% per year. The rate of newly presenting patients infected by transfusion before 1990 decreased, but only by 2.7% per year. The proportion of intravenous (IV) drug users increased by 2.5% per year. Patients presenting “undefined” risk factors increased by 2.1% per year. Nosocomial acquisition of HCV infection exhibited a disturbing relative stability in time whereas dialysis tended to disappear as a cause of infection. There was a significant linear annual decrease of 2.3% in the frequency of genotype 1b, which was counterbalanced by a significant increase of 0.7% for genotype 1a and 1.1% for genotype 4. Genotypes 2 and 3 did not vary significantly with time. Such figures are useful for evaluating the epidemiological changes of C virus infection and for anticipating the future economical cost of hepatitis C treatment in the next few years. J. Med. Virol. 76:503–510, 2005. © 2005 Wiley‐Liss, Inc.
RETRACTED: Small interfering RNA effectively inhibits protein expression and negative strand RNA synthesis from a full‐length hepatitis C virus clone
Authors: Prabhu Ramesh , Vittal Padmaja , Yin Qinyan , Flemington Erik , Garry Robert , Robichaux William H. , Dash Srikanta
Published: June 2005

Hepatitis C virus (HCV) infection is usually treated with the combination of interferon and ribavirin, but only a small fraction of patients develop a sustained remission. There is need for the development of specific molecular approaches for the treatment of chronic HCV infection. We propose that RNA interference is highly effective antiviral strategy that offers great potential for the treatment of HCV infection. Three plasmid constructs expressing small interfering RNAs (siRNAs) targeted to sequences encoding the structural gene (E2) and non‐structural genes (NS3, NS5B) of HCV1a genome were prepared. Antiviral properties of siRNAs against the HCV1a strain were studied in a transient replication model that involved the use of a transcription plasmid containing the full‐length HCV genome and an adenovirus expressing T7 RNA polymerase. We found that siRNAs targeted to the E2, NS3 and NS5B regions of the HCV genome efficiently inhibited expression of the HCV core and NS5A protein measured by Western blot analysis and immunocytochemical staining. Intracytoplasmic immunization of siRNAs in HCV‐transfected cells efficiently degraded genomic positive strand HCV RNA, as shown by ribonuclease protection assay (RPA). All three siRNAs efficiently inhibited synthesis of replicative negative strand HCV RNA in the transfected cells. A control siRNA plasmid against a Epstein–Barr virus latency gene did not inhibit protein expression and negative strand HCV RNA. These results suggest that RNAi is an effective and alternative approach that can be used to inhibit HCV expression and replication. J. Med. Virol. 76:511–519, 2005. © 2005 Wiley‐Liss, Inc.
Surveillance of acute hepatitis C in Cairo, Egypt
Authors: El Gaafary Maha M. , Rekacewicz Claire , Abdel‐Rahman Amira Gamal , Allam Mohamed Farouk , El Hosseiny Mostafa , Hamid Mohamed Abdel , Colombani Françoise , Sultan Yehia , El‐Aidy Saeed , Fontanet Arnaud , Mohamed Mostafa Kamal
Published: June 2005

Surveillance of acute hepatitis has been set up in two fever hospitals in Cairo to diagnose acute hepatitis C. Patients were categorized as definite acute hepatitis C with positive hepatitis C virus (HCV) RNA and without anti‐HCV antibody, or probable acute hepatitis C with positive HCV RNA, positive anti‐HCV antibody, alanine aminotransferase ≥4 times the upper limit of normal (ULN), and high risk parenteral exposure in the 1–3 months prior to the beginning of symptoms. From May to November 2002, 315 patients were recruited in the study. Of these, 115 (36.5%) had acute hepatitis A, 89 (28.3%) had acute hepatitis B, and 111 (35.2%) had non‐A non‐B acute hepatitis. Of the total with complete data (n = 309), 12 (3.9%, 95% CI = 2.0%–6.7%) had definite acute hepatitis C, and 11 (3.6%, 95% CI = 1.8%–6.3%) had probable acute hepatitis C. In patients with definite acute hepatitis C, dental exposure (n = 5) and intravenous drug use (n = 2), were the only high risk procedures found in the 6 months prior to diagnosis. Five patients had no identifiable parenteral exposure. In conclusion, results from this study suggest that acute hepatitis C can be diagnosed by surveillance of acute hepatitis in hospital settings in Cairo and that minor community exposures contribute substantially to local HCV transmission. J. Med. Virol. 76:520–525, 2005. © 2005 Wiley‐Liss, Inc.
Serological and molecular studies on subclinical hepatitis E virus infection using periodic serum samples obtained from healthy individuals
Authors: Mitsui Takehiro , Tsukamoto Yukie , Suzuki Shigeru , Yamazaki Chikao , Masuko Kazuo , Tsuda Fumio , Takahashi Masaharu , Tsatsralt‐Od Bira , Nishizawa Tsutomu , Okamoto Hiroaki
Published: June 2005

Subclinical hepatitis E virus (HEV) infection among healthy individuals was studied serologically and molecularly. Serum samples collected at screening between March and April 2004 (or just before retirement) from 266 medical staff members (35 males, 231 females) who had been working for 8.8 ± 8.5 (mean ± standard deviation, range, 0.3–35.1) years in a city hospital in Japan and serum samples that had been collected from these staff members at the start of employment were tested for IgA, IgM, and IgG antibodies to HEV (anti‐HEV) by in‐house enzyme‐linked immunosorbent assays. Overall, six subjects (2.3%) tested positive for anti‐HEV IgG at the screening; among them, four subjects (1.5%) had already been positive for anti‐HEV IgG at the start of employment and two subjects (0.8%) seroconverted after initiation of employment. Periodic serum samples that had been collected from the two seroconverted subjects were tested for HEV antibodies and HEV RNA. The two subjects became positive for anti‐HEV IgG in 1978 or 2003, respectively, with no discernible elevation in alanine aminotransferase (ALT) level, and continued to be seropositive up through the screening date. Although anti‐HEV IgM was not detectable in the two subjects, one was infected transiently with Japan‐indigenous HEV strain of genotype 3 and the other was positive transiently for anti‐HEV IgA. The present study indicates that even an individual with subclinical HEV infection had evidence of transient viremia in the absence of ALT elevation and that anti‐HEV IgA detection may be useful for serological diagnosis of recent subclinical HEV infection. J. Med. Virol. 76:526–533, 2005. © 2005 Wiley‐Liss, Inc.
Cytomegalovirus and human herpesvirus 8 DNA detection in peripheral blood monocytic cells of AIDS patients: Correlations with the presence of Kaposi's sarcoma and CMV disease
Authors: van der Kuyl Antoinette C. , Polstra Abeltje M. , van den Burg Remco , Jan Weverling Gerrit , Goudsmit Jaap , Cornelissen Marion
Published: June 2005

To establish the effect of the presence in blood cells of cytomegalovirus (CMV) and human herpesvirus 8 (HHV8) DNA, two herpesviruses that are activated frequently in AIDS patients, were selected from the Amsterdam Cohort Studies on HIV/AIDS 181 PBMC samples from patients with and without Kaposi's sarcoma (KS), and with and without CMV‐related disease. The viral loads of both HHV8 and CMV were determined by real‐time PCR at the time of diagnosis of AIDS. There was no significant difference in prevalence and load for CMV between the KS and non‐KS patients. The variable related most strongly to KS was the presence of HHV8 DNA in PBMCs, whilst CMV DNA was related to the development of CMV disease and shortened survival. The frequency of detection of HHV8 increased when the patient presented with more severe KS symptoms at diagnosis, but detection of HHV8 DNA did not influence survival. Therefore, HHV8 and CMV DNA measured in the blood of AIDS patients, are each related mainly to the associated disease, and have no additional predictive value in these patients. J. Med. Virol. 76:541–546, 2005. © 2005 Wiley‐Liss, Inc.
Elevated plasma levels of the long pentraxin, pentraxin 3, in severe dengue virus infections
Authors: Mairuhu Albert T.A. , Peri Giuseppe , Setiati Tatty E. , Hack C. Erik , Koraka Penelopie , Soemantri Augustinus , Osterhaus Albert D.M.E. , Brandjes Dees P.M. , van der Meer Jos W.M. , Mantovani Alberto , van Gorp Eric C.M.
Published: June 2005

C‐reactive protein is one of the most widely used indicators of the response of acute‐phase proteins. The measurement of C‐reactive protein in dengue, however, is clinically not useful, because of marginally elevated levels and absent association with disease severity. The prototypic long pentraxin, pentraxin 3, is an acute phase protein that is structurally related but distinct from C‐reactive protein which has proven to correlate with the severity of bacterial infection in critically ill patients. The potential involvement of pentraxin 3 in dengue and its aptitude to predict more severe disease or poor clinical outcome has not been studied previously. We therefore measured pentraxin 3 plasma levels in 44 dengue virus infected patients. Pentraxin 3 levels were strikingly higher when compared to C‐reactive protein levels, with highest pentraxin 3 values observed in the first 7 days after the onset of symptoms. Median pentraxin 3 levels at admission and peak levels during follow up were higher in patients suffering from dengue shock syndrome (at admission: 119.3 ng/ml [interquartile range 61.8–188.7], peak values during follow up: 147.9 ng/ml [interquartile range 85.7–204.3]) compared to levels found in patients with dengue fever and dengue hemorrhagic fever (at admission: 59.0 ng/ml [interquartile range 28.6–100.3], P = 0.040; peak values during follow up: 80.8 ng/ml [interquartile range 36.1–168.1], P = 0.020). Our results indicate that pentraxin 3 seems to be a marker of infection better than C‐reactive protein in dengue. The role of pentraxin 3 in the pathogenesis of dengue and its potential as an early prognostic indicator of disease severity needs further assessment. J. Med. Virol. 76:547–552, 2005. © 2005 Wiley‐Liss, Inc.
Hantaviruses in Central South America: Phylogenetic analysis of the S segment from HPS cases in Paraná, Brazil
Authors: Raboni Sonia M. , Probst Christian M. , Bordignon Juliano , Zeferino Aurélio , dos Santos Claudia N. Duarte
Published: June 2005

We sequenced the complete S segments of hantaviruses detected from 12 HPS patients living in southern of Brazil. Samples were obtained from patients diagnosed in different years, in distinct areas, and with a broad spectrum of clinical signs. Despite these differences, all the S proteins of hantavirus from Paraná were identical, except for one amino acid substitution. Phylogenetic analyses of the complete S segment nucleotide and amino acid sequences indicated that hantaviruses from Paraná form a distinct clade from those circulating in South and North America. Other hantaviruses from Brazil were not placed in the same clade. The Oligoryzomys nigripes‐associated strains ITA37 and ITA38 from Paraguay were found to belong to the same clade as the hantaviruses from Paraná. Paraguay and Paraná state are located at the same latitude and some ecosystems are similar in both places. The geographic position and common rodent hosts could explain this phylogenetic relationship. J. Med. Virol. 76:553–562, 2005. © 2005 Wiley‐Liss, Inc.