bluuebunny/crossref_metadata_2025 huggingface dataset:
Modal Approximation of Distributed Dynamics for a Hydraulic Transmission Line With Pressure Input-Flow Rate Output Causality
Authors: Ayalew Beshahwired , Kulakowski Bohdan T.
Published: August 2005

Based on analytical results obtained in the frequency domain, modal approximation techniques are employed to derive transfer function and state space models applicable to a pressure input-flow rate output causality case of a transmission line. The causality case considered here arises while modeling short connection lines to hydraulic accumulators. However, the modal approximation results presented apply also to other cases where the linear friction model is considered applicable. It is highlighted that the results presented can reduce the overall order of the hydraulic system model containing the transmission line being considered.
Persistence of Zinc-Binding Bacterial Superantigens at the Surface of Antigen-Presenting Cells Contributes to the Extreme Potency of These Superantigens as T-Cell Activators
Authors: Pless Dorothy D. , Ruthel Gordon , Reinke Emily K. , Ulrich Robert G. , Bavari Sina
Published: August 2005

Bacterial superantigen intoxication causes massive overactivation of T cells, which can result in potentially lethal toxic shock. Superantigens fall into two groups: superantigens such as staphylococcal enterotoxin B (SEB) that contain a single generic binding site for major histocompatibility complex class II (MHC-II) and more potent superantigens such as SEA with a second, zinc-dependent MHC-II binding site that enables them to cross-link adjacent MHC-II molecules. We found that although all superantigens bound rapidly to the surface of human B cells, zinc-binding superantigens largely remained at the cell surface for at least 40 h. In contrast, single-binding-site superantigens were greatly depleted from the surface by 4 h. Subcellular fractionation and confocal microscopy revealed that some SEB entered lysosomal compartments, but SEA remained almost undetectable inside cells at 20 h. SEA and SEB mutants that do not bind MHC-II were trafficked rapidly to lysosomal compartments. Our findings suggest that the persistence of SEA and other zinc-dependent, cross-linking superantigens on the surface of antigen-presenting cells contributes to their potency as T-cell activators.
Identification, Cloning, Expression, and Characterization of the Gene for
Plasmodium knowlesi
Surface Protein Containing an Altered Thrombospondin Repeat Domain
Authors: Mahajan Babita , Jani Dewal , Chattopadhyay Rana , Nagarkatti Rana , Zheng Hong , Majam Victoria , Weiss Walter , Kumar Sanjai , Rathore Dharmendar
Published: August 2005

Proteins present on the surface of malaria parasites that participate in the process of invasion and adhesion to host cells are considered attractive vaccine targets. Aided by the availability of the partially completed genome sequence of the simian malaria parasite
Plasmodium knowlesi
, we have identified a 786-bp DNA sequence that encodes a 262-amino-acid-long protein, containing an altered version of the thrombospondin type I repeat domain (SPATR). Thrombospondin type 1 repeat domains participate in biologically diverse functions, such as cell attachment, mobility, proliferation, and extracellular protease activities. The SPATR from
P. knowlesi
(PkSPATR) shares 61% and 58% sequence identity with its
Plasmodium falciparum
and
Plasmodium yoelii
orthologs, respectively. By immunofluorescence analysis, we determined that PkSPATR is a multistage antigen that is expressed on the surface of
P. knowlesi
sporozoite and erythrocytic stage parasites. Recombinant PkSPATR produced in
Escherichia coli
binds to a human hepatoma cell line, HepG2, suggesting that PkSPATR is a parasite ligand that could be involved in sporozoite invasion of liver cells. Furthermore, recombinant PkSPATR reacted with pooled sera from
P. knowlesi
-infected rhesus monkeys, indicating that native PkSPATR is immunogenic during infection. Further efficacy evaluation studies in the
P. knowlesi
-rhesus monkey sporozoite challenge model will help to decide whether the SPATR molecule should be developed as a vaccine against human malarias.
Identification of a New Virulence Factor, BvfA, in
Brucella suis
Authors: Lavigne Jean-Philippe , Patey Gilles , Sangari Felix J. , Bourg Gisèle , Ramuz Michel , O'Callaghan David , Michaux-Charachon Sylvie
Published: August 2005

We report the identification of BvfA (for
Brucella
virulence factor A), a small periplasmic protein unique to the genus
Brucella
, which is essential for the virulence of
Brucella suis
. A BvfA knockout mutant was highly attenuated both in in vitro macrophage infection assays and in vivo in the murine model of brucellosis. Fluorescence-activated cell sorting analysis with green fluorescent protein fusions showed that the expression of
bvfA
is induced within macrophages by phagosome acidification and coregulated with the
B. suis virB
operon, suggesting that it too may play a role in the establishment of the intracellular replication niche.
Optimization of Codon Usage Enhances the Immunogenicity of a DNA Vaccine Encoding Mycobacterial Antigen Ag85B
Authors: Ko Hyun-Jeong , Ko Sung-Youl , Kim Yeon-Jeong , Lee Eun-Gae , Cho Sang-Nae , Kang Chang-Yuil
Published: August 2005

In spite of its many other benefits, DNA vaccine is limited in its application by its insufficient immunogenicity. One promising approach for enhancing its immunogenicity is to maximize its expression in the immunized host. In the current study, we investigated whether codon optimization of the mycobacterial antigen Ag85B gene could enhance the expression and immunogenicity of the Ag85B DNA vaccine. We generated a synthetic humanized Ag85B (hAg85B) gene in which codon usage was optimized for expression in human cells. DNA plasmids with codon-optimized hAg85B increased the level of protein expression in vitro and in vivo. DNA vaccine with hAg85B induced stronger Th1-like and cytotoxic T-cell immune responses in BALB/c mice and generated higher protective immunity in a BALB/c mouse model ofMycobacterium tuberculosisaerosol infection than did the DNA vaccine with wild-type Ag85B. Therefore, our results suggest that codon optimization of mycobacterial antigens (e.g., Ag85B) could improve protein expression and thereby enhance the immunogenicity of DNA vaccines againstM. tuberculosis.
HLA-A2 Supertype-Restricted Cell-Mediated Immunity by Peripheral Blood Mononuclear Cells Derived from Malian Children with Severe or UncomplicatedPlasmodium falciparumMalaria and Healthy Controls
Authors: Lyke Kirsten E. , Burges Robin B. , Cissoko Yacouba , Sangare Lansana , Kone Abdoulaye , Dao Modibo , Diarra Issa , Fernández-Viňa Marcelo A. , Plowe Christopher V. , Doumbo Ogobara K. , Sztein Marcelo B.
Published: August 2005

Understanding HLA-restricted adaptive host immunity to defined epitopes of malarial antigens may be required for the development of successful malaria vaccines. Fourteen epitopes of preerythrocytic malarial antigens known to mediate cytotoxic T-lymphocyte responses against target cells expressing HLA-A2-restricted epitopes were synthesized and pooled based on antigen: thrombospondin-related anonymous protein (TRAP), circumsporozoite protein (CSP), and export protein 1 (Exp-1) peptides. HLA-A2 supertype (*0201, *0202, *0205, *6802) peripheral blood mononuclear cells collected from 774 Malian children, aged 3 months to 14 years, with severePlasmodium falciparummalaria matched to uncomplicated malaria or healthy controls were stimulated with the HLA-A2-restricted peptide pools. Significant gamma interferon production, determined by enzyme-linked immunospot assay to at least one of the three peptide pools, was observed in 24/58 (41%) of the severe malaria cases, 24/57 (42%) of the uncomplicated malaria cases, and 34/51 (67%) of the healthy controls. Significant lymphoproliferation to these peptides was observed in 12/44 (27%) of the severe malaria cases, 13/55 (24%) of the uncomplicated malaria cases, and 18/50 (36%) of the healthy controls. Responses to individual peptide pools were limited. These studies confirm the presence of adaptive cell-mediated immunity to preerythrocytic malaria antigens in volunteers from Mali and demonstrate that suballeles of the HLA-A2 supertype can effectively present antigenic epitopes. However, whether these immune responses to TRAP, CSP, and Exp-1 malarial proteins play a substantial role in protection remains a matter of controversy.
Placental Malaria Induces Variant-Specific Antibodies of the Cytophilic Subtypes Immunoglobulin G1 (IgG1) and IgG3 That Correlate with Adhesion Inhibitory Activity
Authors: Elliott Salenna R. , Brennan Amy K. , Beeson James G. , Tadesse Eyob , Molyneux Malcolm E. , Brown Graham V. , Rogerson Stephen J.
Published: August 2005

Antibodies targeting variant antigens on the surfaces of chondroitin sulfate A (CSA)-binding malaria-infected erythrocytes have been linked to protection against the complications of malaria in pregnancy. We examined the isotype/subtype profiles of antibodies that bound to variant surface antigens expressed by CSA-adherent
Plasmodium falciparum
in pregnant Malawian women with and without histologically defined placental malaria. Women in their first pregnancy with placental malaria produced significantly greater amounts of immunoglobulin G1 (IgG1) and IgG3 reactive with surface antigens of malaria-infected erythrocytes than uninfected women of the same gravidity. IgG1 and IgG3 levels in infected and control women in later pregnancies were similar to those in infected women in their first pregnancy. Levels of IgG2 and IgG4 were similarly low in infected and uninfected women of all gravidities. IgM that bound to the surface of CSA-adherent
P. falciparum
occurred in all groups of women and malaria-naïve controls. There was a significant correlation between IgG1 and IgG3 levels, indicating that women usually produced both subtypes. Levels of IgG1 and IgG3 correlated with the ability of serum or plasma to inhibit parasite adhesion to CSA. Taken together, these data suggest that IgG1 and IgG3 dominate the IgG response to placental-type variant surface antigens. They may function by blocking parasite adhesion to placental CSA, but given their cytophilic nature, they might also opsonize malaria-infected erythrocytes for interaction with Fc receptors on phagocytic cells.
Transforming Growth Factor β1 Production by CD4+CD25+Regulatory T Cells in Peripheral Blood Mononuclear Cells from Healthy Subjects Stimulated withLeishmania guyanensis
Authors: Kariminia A. , Bourreau E. , Pascalis H. , Couppié P. , Sainte-Marie D. , Tacchini-Cottier F. , Launois P.
Published: August 2005

Transforming growth factor β (TGF-β) has been shown to be a central immunomodulator used by leishmaniae to escape effective mechanisms of protection in human and murine infections with these parasites. However, all the information is derived from studies of established infection, while little is known about TGF-β production in response toLeishmaniastimulation in healthy subjects. In this study, TGF-β1 production was demonstrated in peripheral blood mononuclear cells from healthy subjects never exposed to leishmaniae in response to liveLeishmania guyanensis, and the TGF-β1-producing cells were described as a distinct subpopulation of CD4+CD25+regulatory T cells. The suppressive properties of CD4+CD25+T cells were demonstrated in vitro by their inhibition of production of interleukin 2 (IL-2) and IL-10 by CD4+CD25−T cells in the presence of either anti-CD3 orL. guyanensis. Although neutralization of TGF-β1 did not reverse the suppressive activity of CD4+CD25+T cells activated by anti-CD3, it reversed the suppressive activity of CD4+CD25+T cells activated byL. guyanensis. Altogether our data demonstrated that TGF-β1 is involved in the suppressive activity ofL. guyanensis-stimulated CD4+CD25+T cells from healthy controls.
Quantitative Assessment of Protection in Experimental Syphilis
Authors: Champion Cheryl I. , Blanco David R. , Lovett Michael A.
Published: August 2005

Protection in experimental rabbit syphilis has been previously assessed by lesion development following intradermal challenge withTreponema pallidum. We have recently reported that passive immunization using monoclonal antibody M131 conveys partial protection as evidenced by significant lesion delays following intradermal challenge (D. R. Blanco et al., Infect. Immun.73:3083-3095, 2005). To determine whether such delays in time to lesion appearance corresponded to decreases in the numbers of spirochetes, we used real-time PCR to quantitateT. pallidumgenomic DNA copy numbers in lesion biopsies taken throughout the course of lesion development. Three groups of animals were given one prechallenge passive immunization with immune rabbit serum (IRS), M131, or control monoclonal antibody (CMAb) and then challenged with treponemal admixtures of IRS or monoclonal antibody in normal rabbit serum (NRS). As compared to the CMAb NRS controls, delays in the mean time to lesion appearance of 5.8 days for IRS and 8.8 days for M131 were observed. At the earliest time point (10 days postchallenge), real-time PCR showed a meanT. pallidumDNA copy number per μg of rabbit DNA in the CMAb NRS group of 7.65 × 103copies, while noT. pallidumDNA could be detected in the M131 group. At approximately the mean time to lesion appearance in the IRS and M131 groups (17 and 20 days, respectively), the numbers ofT. pallidumDNA copies were still 5- and 30-fold less, respectively, than those in the control group at these times. By 30 days postchallenge, theT. pallidumDNA copy numbers were similar in all three groups. These findings indicate that the delays in appearance of syphilitic lesions conferred by IRS and M131 corresponded to a marked decrease in treponemal numbers during the course of lesion development.
Extensive Antigenic Polymorphism within the Repeat Sequence of thePlasmodium falciparumMerozoite Surface Protein 1 Block 2 Is Incorporated in a Minimal Polyvalent Immunogen
Authors: Tetteh Kevin K. A. , Cavanagh David R. , Corran Patrick , Musonda Rosemary , McBride Jana S. , Conway David J.
Published: August 2005

Polymorphism in pathogen antigens presents a complex challenge for vaccine design. A prime example is the N-terminal block 2 region of thePlasmodium falciparummerozoite surface protein 1 (MSP1), to which allele-specific antibodies have been associated with protection from malaria. In a Zambian population studied here, 49 of 91 alleles sampled were of the K1-like type (the most common of three block 2 types in all African populations), and most of these had unique sequences due to variation in tri- and hexapeptide repetitive motifs. There were significant negative correlations between allelic sequence lengths of different regions of the repeats, so the complete repeat sequence had less length variation than its component parts, suggesting a constraint on overall length. Diverse epitopes recognized by three murine monoclonal antibodies and 24 individual human sera were then mapped by using a comprehensive panel of synthetic peptides, revealing epitopes in all regions of the repeats. To incorporate these different epitopes in a single molecule, a composite sequence of minimal overall length (78 amino acids) was then designed and expressed as a recombinant antigen. More human immune sera reacted with this “K1-like Super Repeat” antigen than with proteins consisting of single natural allelic sequences, and immunization of mice elicited antibodies that recognized a range of five cultured parasite lines with diverse K1-like MSP1 block 2 repeat sequences. Thus, complex allelic polymorphism was deconstructed and a minimal composite polyvalent antigen was engineered, delivering a designed candidate sequence for inclusion in a malaria vaccine.
Synergy in Polymicrobial Infections in a Mouse Model of Type 2 Diabetes
Authors: Mastropaolo Matthew D. , Evans Nicholas P. , Byrnes Meghan K. , Stevens Ann M. , Robertson John L. , Melville Stephen B.
Published: August 2005

Human diabetics frequently suffer delayed wound healing, increased susceptibility to localized and systemic infections, and limb amputations as a consequence of the disease. Lower-limb infections in diabetic patients are most often polymicrobial, involving mixtures of aerobic, facultative anaerobic, and anaerobic bacteria. The purpose of this study is to determine if these organisms contribute to synergy in polymicrobial infections by using diabetic mice as an in vivo model. The model was the obese diabetic mouse strain BKS.Cg-m+/+Leprdb/J, a model of human type 2 diabetes. Young (5- to 6-week-old) prediabetic mice and aged (23- to 24-week-old) diabetic mice were compared. The mice were injected subcutaneously with mixed cultures containingEscherichia coli,Bacteroides fragilis, andClostridium perfringens. Progression of the infection (usually abscess formation) was monitored by examining mice for bacterial populations and numbers of white blood cells at 1, 8, and 22 days postinfection. Synergy in the mixed infections was defined as a statistically significant increase in the number of bacteria at the site of injection when coinfected with a second bacterium, compared to when the bacterium was inoculated alone.E. coliprovided strong synergy toB. fragilisbut not toC. perfringens. C. perfringensandB. fragilisprovided moderate synergy to each other but only in young mice.B. fragiliswas anergistic (antagonistic) toE. coliin coinfections in young mice at 22 days postinfection. When age-matched nondiabetic mice (C57BLKS/J) were used as controls, the diabetic mice exhibited 5 to 35 times the number of CFU as did the nondiabetic mice, indicating that diabetes was a significant factor in the severity of the polymicrobial infections.
FEMTOSCOPY IN RELATIVISTIC HEAVY ION COLLISIONS: Two Decades of Progress
Authors: Lisa Michael Annan , Pratt Scott , Soltz Ron , Wiedemann Urs
Published: August 2005

▪ Abstract  Analyses of two-particle correlations have provided the chief means for determining spatio-temporal characteristics of relativistic heavy ion collisions. We discuss the theoretical formalism behind these studies and the experimental methods used in carrying them out. Recent results from RHIC are put into context in a systematic review of correlation measurements performed over the past two decades. The current understanding of these results is discussed in terms of model comparisons and overall trends.
Helicobacter pyloriand cholesterol gallstone formation in C57L/J mice: a prospective study
Authors: Maurer Kirk J. , Rogers Arlin B. , Ge Zhongming , Wiese Ashley J. , Carey Martin C. , Fox James G.
Published: August 2005

Recently, we demonstrated that cholesterol gallstone-prone C57L/J mice rarely develop gallstones unless they are infected with certain cholelithogenic enterohepatic Helicobacter species. Because the common gastric pathogen H. pylori has been identified in the hepatobiliary tree of cholesterol gallstone patients, we wanted to ascertain if H. pylori is cholelithogenic, by prospectively studying C57L infected mice fed a lithogenic diet. Weanling, Helicobacter spp.-free male C57L mice were either infected with H. pylori SS1 or sham dosed. Mice were then fed a lithogenic diet (1.0% cholesterol, 0.5% cholic acid, and 15% dairy triglycerides) for 8 wk. At 16 wk of age, mice were euthanatized, the biliary phenotype was analyzed microscopically, and tissues were analyzed histopathologically. H. pylori infection did not promote cholesterol monohydrate crystal formation (20% vs. 10%), sandy stone formation (0% for both), or true gallstone formation (20%) compared with uninfected mice fed the lithogenic diet (10%). Additionally, H. pylori failed to stimulate mucin gel accumulation in the gallbladder or alter gallbladder size compared with uninfected animals. H. pylori-infected C57L mice developed moderate to severe gastritis by 12 wk, and the lithogenic diet itself produced lesions in the forestomach, which were exacerbated by the infection. We conclude that H. pylori infection does not play any role in murine cholesterol gallstone formation. Nonetheless, the C57L mouse develops severe lesions of both the glandular and nonglandular stomach in response to H. pylori infection and the lithogenic diet, respectively.
Regulation of hydraulic conductivity in response to sustained changes in pressure
Authors: Kim Min-ho , Harris Norman R. , Tarbell John M.
Published: August 2005

The present study addresses the effect of a sustained change in pressure on microvascular permeability assessed by hydraulic conductivity ( Lp) measurements from microvessels of the rat mesentery. With a microperfusion technique, transvascular filtration (normalized to surface area; Jv/ S) and Lp were measured in small arterioles (baseline Lp = 0.26 × 10−7 cm·s−1·cmH2O−1) and venules (baseline Lp = 2.88 × 10−7 cm·s−1·cmH2O−1). The main finding of this study is that step increases in microvascular pressure led to time-dependent alterations of Lp. Immediately after a twofold step increase in pressure, Jv/ S increased in proportion to the pressure change. This observation is consistent with Starling's law that predicts filtration proportional to the overall pressure gradient when Lp is constant. However, when Jv/ S measurements continued for 60–90 min past the step in pressure, there was an initial decrease in Jv/ S for 30 min (“sealing effect”) followed by a substantial increase in Jv/ S out to 90 min. The sustained increase in Jv/ S suggests an increase in Lp of 36 ± 7% for small arterioles and 42 ± 5% for small venules ( P < 0.05 for both). In addition, the increase in Lp in response to an increase in pressure was attenuated significantly by nitric oxide synthase inhibition. These results indicate that a pressure-induced mechanical stimulus (possibly Jv) activates a NO-dependent biochemical response that leads to an increase in hydraulic conductivity.
Intronic ANG II type 2 receptor gene polymorphism 1675 G/A modulates receptor protein expression but not mRNA splicing
Authors: Warnecke Christina , Mugrauer Peter , Sürder Daniel , Erdmann Jeanette , Schubert Carola , Regitz-Zagrosek Vera
Published: August 2005

The X-linked ANG II type 2 receptor (AT2) is supposed to be involved in cardiovascular disorders. Two studies associated the A allele of the AT2 gene polymorphism (PM) 1675 G/A with left ventricular hypertrophy in men and coronary ischemia in women. Because the PM is located in the short intron 1 of the AT2 gene within a sequence motif similar to the splice branch site consensus, we tested whether it might affect pre-mRNA splicing and/or modulate AT2 receptor expression. We first analyzed the AT2 mRNA splice pattern by RT-PCR in myocardial samples from 12 explanted human hearts and compared it with the respective genotypes. All 12 patients, 10 hemizygous males (7 A, 3 G allele carriers) and 2 homozygous females (2 G/G allele carriers), exhibited the same myocardial AT2 splice pattern with a relative abundance of transcript exon 1/2/3 compared with exon 1/3. Next, AT2 minigene constructs were cloned from both alleles, comprising the core promoter and the complete transcribed region up to the translation start codon, upstream of a luciferase reporter gene. These constructs were transfected into human (HT1080) and rat (PC12W) cell lines and rat vascular smooth muscle cells, and luciferase activities were assessed, as well as the splice patterns of the chimeric AT2/luciferase mRNAs. In all transfected cell types, the mRNA expressed from the AT2 constructs was spliced like the endogenous myocardial AT2 mRNA. However, luciferase activities driven by the G allele construct were significantly higher than those expressed from the A allele. Taken together, these data indicate that individuals carrying the G allele may express higher levels of AT2 receptor protein, which may be protective during the development of ventricular hypertrophy and coronary ischemia.
Time course of lung parenchyma remodeling in pulmonary and extrapulmonary acute lung injury
Authors: Santos Flavia B. , Nagato Lilian K. S. , Boechem Nicolau M. , Negri Elnara M. , Guimarães Alberto , Capelozzi Vera L. , Faffe Debora S. , Zin Walter A. , Rocco Patricia R. M.
Published: August 2005

The aim of this study is to test the hypothesis that the early changes in lung mechanics and the amount of type III collagen fiber do not predict the evolution of lung parenchyma remodeling in pulmonary and extrapulmonary acute lung injury (ALI). For this purpose, we analyzed the time course of lung parenchyma remodeling in murine models of pulmonary and extrapulmonary ALI with similar degrees of mechanical compromise at the early phase of ALI. Lung histology (light and electron microscopy), the amount of elastic and collagen fibers in the alveolar septa, the expression of matrix metalloproteinase-9, and mechanical parameters (lung-resistive and viscoelastic pressures, and static elastance) were analyzed 24 h, 1, 3, and 8 wk after the induction of lung injury. In control (C) pulmonary (p) and extrapulmonary (exp) groups, saline was intratracheally (it; 0.05 ml) instilled and intraperitoneally (ip; 0.5 ml) injected, respectively. In ALIp and ALIexp groups, mice received Escherichia coli lipopolysaccharide (10 μg it and 125 μg ip, respectively). At 24 h, all mechanical and morphometrical parameters, as well as type III collagen fiber content, increased similarly in ALIp and ALIexp groups. In ALIexp, all mechanical and histological data returned to control values at 1 wk. However, in ALIp, static elastance returned to control values at 3 wk, whereas resistive and viscoelastic pressures, as well as type III collagen fibers and elastin, remained elevated until week 8. ALIp showed higher expression of matrix metalloproteinase-9 than ALIexp. In conclusion, insult in pulmonary epithelium yielded fibroelastogenesis, whereas mice with ALI induced by endothelial lesion developed only fibrosis that was repaired early in the course of lung injury. Furthermore, early functional and morphological changes did not predict lung parenchyma remodeling.
Identification of Myosin Heavy Chain I, IIa and IIx in Canine Skeletal Muscles by an Electrophoretic and Immunoblotting Study
Authors: Smerdu V. , Štrbenc M. , Meznarič-Petruša M. , Fazarinc G.
Published: August 2005

To determine which myosin heavy chain (MHC) isoforms are expressed in canine skeletal muscles, different muscle samples of five mixed-breed dogs were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The separated MHC isoforms were identified by immunoblotting technique using a set of specific monoclonal antibodies. To compare the results of the electrophoretic and immunoblotting study, the pattern of MHC isoform expression and histochemical profiles of canine fibres were additionally demonstrated on serial muscle sections by immunohistochemistry and myofibrillar adenosine triphosphatase (mATPase) histochemistry. Not more than three MHC isoforms were demonstrated by SDS-PAGE in the analysed canine muscles. By the immunoblotting technique, the fastest migrating MHC band was identified as slow or MHC-I, the intermediate one as MHC-IIx and the slowest migrating band as MHC-IIa isoform. Since none of the three MHC bands and none of the analysed fibres were recognized by the antibody specific to MHC-IIb of rats, we concluded that MHC-IIb is not expressed in large skeletal muscles of dogs. Similarly, only three major fibre types, i.e. I, IIA and IIX, were revealed according to the pattern of MHC immunohistochemistry and mATPase reaction. Type IIA fibres were more alkali- and acid-stable than type IIX fibres after mATPase histochemistry; hence, the latter corresponded to type IIDog fibres. However, beside the three major fibre types, scarce hybrid fibres co-expressing two MHC isoforms (I/IIA and IIA/IIX) were demonstrated by immunohistochemistry.
Attitudes and Misconceptions about Predictive Genetic Testing for Cancer Risk
Authors: Rose Abigail L. , Peters Nikki , Shea Judy A. , Armstrong Katrina
Published: August 2005

Objective: To describe awareness, knowledge, and attitudes about genetic testing for cancer risk among the general public. Results: Thirty-eight adults participated in focus groups in West Philadelphia, Pennsylvania. Participants’ beliefs about what genetic testing is ranged from ‘dianetics’ to an accurate description of DNA analysis. Themes included misconceptions about genetic tests, the ability to gain control of one’s life through genetic testing, anxiety that might be caused by testing, risk of insurance and employment discrimination, use of genetic information for racial or ethnic discrimination, concerns about medical information confidentiality and lack of informed consent. Conclusions: Although there was some accurate understanding of what genetic testing is and how the results could be used, there also exist significant misconceptions. In many cases, misconceptions may be barriers to uptake of genetic testing. Dispelling these misconceptions is an important step in the translation of advances in human genomics into improvements in health.
Prevalence of Three Hereditary Hemochromatosis Mutant Alleles in the Michigan Caucasian Population
Authors: Barry Elizabeth , Derhammer Teresa , Elsea Sarah H.
Published: August 2005

Objective: To investigate the prevalence in the Michigan non-Hispanic Caucasian population of the C282Y, H63D and S65C mutations in the HFE gene associated with hereditary hemochromatosis. Methods: Polymerase chain reaction and restriction fragment length polymorphism analysis were performed on 3,532 blood samples from newborn screening cards provided by the state of Michigan. Results: More than 30% of Michigan Caucasians carry one HFE mutation, while 6% have two mutations. The allele frequency of the C282Y mutation is 5.7%, significantly higher than expected (p < 0.05), while the frequency of the H63D mutation is 14%, significantly lower than expected (p < 0.01). Conclusions: This is the first publication to examine HFE allele frequencies in an unbiased sample of the Caucasian population. Results indicate that the C282Y mutation may be more common in the non-Hispanic Caucasian population than previously reported, and medical problems related to iron overload may be a health concern for Michigan non-Hispanic Caucasians. Additional studies of penetrance for the C282Y allele are required to fully understand the impact of this information.
In vivo Evaluation of Limonene-Based Transdermal Therapeutic System of Nicorandil in Healthy Human Volunteers
Authors: Krishnaiah Y.S.R. , Chandrasekhar D.V. , Rama B. , Jayaram B. , Satyanarayana V. , Al-Saidan S.M.
Published: August 2005

Hydroxypropyl methylcellulose (HPMC) gel drug reservoir system prepared with 70:30 v/v ethanol-water solvent system containing 6% w/w of limonene was effective in promoting the in vitro transdermal delivery of nicorandil. The objective of the present study was to fabricate and evaluate a limonene-based transdermal therapeutic system (TTS) for its ability to provide the desired steady-state plasma concentration of nicorandil in human volunteers. The in vitro permeation of nicorandil from a limonene-based HPMC gel drug reservoir was studied across excised rat skin (control), EVA2825 membrane, adhesive-coated EVA2825 membrane and adhesive-coated EVA2825 membrane-excised rat skin composite to account for their effect on the desired flux of nicorandil. The flux of nicorandil from the limonene-based HMPC drug reservoir across EVA2825 membrane decreased to 215.8 ± 9.7µg/cm2·h when compared to that obtained from control, indicating that EVA2825 was effective as a rate-controlling membrane. The further decrease in nicorandil flux across adhesive-coated EVA2825 membrane and adhesive-coated EVA2825 membrane-excised rat skin composite showed that the adhesive coat and skin also controlled the in vitro transdermal delivery. The limonene-based drug reservoir was sandwiched between adhesive-coated EVA2825-release liner composite and a backing membrane. The resultant sandwich was heat-sealed as circle-shaped patch (20 cm2), trimmed and subjected to in vivo evaluation in human volunteers against immediate-release tablets of nicorandil (reference formulation). The fabricated limonene-based TTS of nicorandil provided a steady-state plasma concentration of 21.3 ng/ml up to 24 h in healthy human volunteers. It was concluded that the limonene-based TTS of nicorandil provided the desired plasma concentration of the drug for the predetermined period of time with minimal fluctuations and improved bioavailability.
Heterotaxy Syndrome – Asplenia and Polysplenia as Indicators of Visceral Malposition and Complex Congenital Heart Disease
Authors: Bartram Ulrike , Wirbelauer Johannes , Speer Christian P.
Published: August 2005

Heterotaxy results from failure of the developing embryo to establish normal left-right asymmetry. Typical manifestations include abnormal symmetry and malposition of the thoraco-abdominal organs and vessels, complex congenital heart disease and extracardiac defects involving midline-associated structures. The spleen is almost always affected, and there is syndromic clustering of the malformations corresponding to the type of splenic abnormality present. This review outlines the embryologic and genetic background of the heterotaxy syndrome as well as the characteristic anatomic features, clinical manifestations, and diagnostic clues of its two main presentations with asplenia or polysplenia.
Neuroprotective Effect of L-Arginine in a Newborn Rat Model of Acute Severe Asphyxia
Authors: Martínez-Orgado J. , Fernández-Frutos B. , González R. , Fernández-López D. , Urigüen L. , Romero E. , Moro M. , Bonet B. , Viveros M.P.
Published: August 2005

The left common carotid artery was ligated in anaesthetized 7-day-old Wistar rats (P7), prior to asphyxia by inhaling 100% nitrogen for 9 min. Pups recovered from asphyxia received i.p. saline (n = 16), or L-Arg 300 mg/kg (n = 14). Pups undergoing sham operation remained as controls (n = 12). At day 14, the amount of surviving or degenerating neurons was quantified under optical microscopy by Nissl technique or by Fluoro-Jade B (FJB) in CA1 area of hippocampus and in parietal cortex. In these areas, asphyxia reduced the neuronal density by 23.6 and 30%, and increased the proportion of degenerating neurons two and four times, respectively. L-Arg administration to asphyxiated pups reduced the neuronal loss and the proportion of degenerating neurons by 50% (p < 0.05). We conclude that L-Arg administration after acute severe asphyxia in newborn rats is neuroprotective, reducing early and delayed neuronal loss.
Is Lactobacillus rhamnosus GG Effective in Preventing the Onset of Antibiotic-Associated Diarrhoea: A Systematic Review
Authors: Hawrelak Jason A. , Whitten Dawn L. , Myers Stephen P.
Published: August 2005

Objective: To evaluate the efficacy of Lactobacillus rhamnosus GG in the prevention of antibiotic-associated diarrhoea. Data Sources: A computer-based search of MEDLINE, CINAHL, AMED, the Cochrane Controlled Trials Register and the Cochrane Database of Systematic Reviews was conducted. A hand-search of the bibliographies of relevant papers and previous meta-analyses was undertaken. Review Methods: Trials were included in the review if they compared the effects of L. rhamnosus GG and placebo and listed diarrhoea as a primary end-point. Studies were excluded if they were not placebo-controlled or utilised other probiotic strains. Results: Six trials were found that met all eligibility requirements. Significant statistical heterogeneity of the trials precluded meta-analysis. Four of the six trials found a significant reduction in the risk of antibiotic-associated diarrhoea with co-administration of Lactobacillus GG. One of the trials found a reduced number of days with antibiotic-induced diarrhoea with Lactobacillus GG administration, whilst the final trial found no benefit of Lactobacillus GG supplementation. Conclusion: Additional research is needed to further clarify the effectiveness of Lactobacillus GG in the prevention of antibiotic-associated diarrhoea.
Outcomes of Adults with Cystic Fibrosis Infected with Antibiotic-Resistant Pseudomonas aeruginosa
Authors: Lechtzin Noah , John Majnu , Irizarry Rafael , Merlo Christian , Diette Gregory B. , Boyle Michael P.
Published: August 2005

Background: Although Pseudomonas aeruginosa is the most common bacterial infection in adults with cystic fibrosis and frequently develops resistance to multiple classes of antibiotics, it has not been determined whether patients with multiple antibiotic-resistant Pseudomonas aeruginosa have worse clinical outcomes than patients with more susceptible strains. Objectives: This study assessed the impact of multiply-resistant P. aeruginosa on lung function, hospitalizations, antibiotic use, lung transplantation and survival in adults with cystic fibrosis. Methods: In a cohort study at a university-based adult cystic fibrosis program, 75 consecutive adult cystic fibrosis patients who had P. aeruginosa isolated from sputum cultures were studied over a 4-year period. Outcomes included decline in FEV1, clinic visits, hospitalizations, courses and days of intravenous antibiotics, and lung transplantation. Multiple linear and Poisson regression for repeated measures were used to assess the outcomes. Results: In comparison to patients with susceptible strains, patients with resistant P. aeruginosa had more severe baseline lung disease, more rapid decline in FEV1 (160 ml/year, p = 0.003) and were significantly more likely to undergo lung transplantation (17.6 vs. 0%, p = 0.005). Conclusions: Infection with multiple-antibiotic-resistant P. aeruginosa is associated with accelerated progression of cystic fibrosis, and has important implications for infection control strategies, antibiotic use and lung transplantation.
High Prevalence of Mycobacterium tuberculosis DNA in Biopsies from Sarcoidosis Patients from Catalonia, Spain
Authors: Fité E. , Fernández-Figueras M.T. , Prats R. , Vaquero M. , Morera J.
Published: August 2005

Background: Sarcoidosis is a systemic granulomatous disease of unknown etiology. The presence of mycobacterial nucleic acid components in patients with sarcoidosis has been demonstrated with varying degrees of success. Objectives: The aim of this study was to estimate the presence of Mycobacterium tuberculosis DNA in tissues from sarcoidosis patients, in Catalonia, Spain, as well as to assess the long-term clinical course in these patients. Methods: Fifty-eight paraffin-embedded tissue biopsies corresponding to cases of sarcoidosis (n = 23), lung neoplasm (n = 23), and lung tuberculosis (n = 12) available in 1996 were analyzed in a retrospective study by means of a nested polymerase chain reaction using primers corresponding to the insertion element IS6110 of M. tuberculosis complex. For greater sensitivity, Southern blot hybridization was performed. Clinical data were recorded prior to and after PCR analysis (follow-up reported until 2002). Results:M. tuberculosis DNA was present in 9 out of 23 sarcoidosis biopsies (39%), in 1 out of 23 control patients (4%) (p < 0.01), and in all tissue samples from the 12 control patients with tuberculosis. To date, none of these sarcoidosis patients has developed tuberculosis over a mean (±SD) follow-up period of 11 (±3.4) years. Conclusion: In our setting, M. tuberculosis DNA is present in tissue biopsies of significantly more sarcoidosis patients than controls. However, these results do not demonstrate causality, although they may suggest a link between M. tuberculosis infection and sarcoidosis in some cases. Follow-up of these patients suggests that M. tuberculosis-DNA-positive sarcoidosis patients are not at greater risk of developing tuberculosis than M. tuberculosis-DNA-negative patients.
Stability-Dependent Exchange Coefficients for Air–Sea Fluxes*
Authors: Kara A. Birol , Hurlburt Harley E. , Wallcraft Alan J.
Published: August 2005

This study introduces exchange coefficients for wind stress (CD), latent heat flux (CL), and sensible heat flux (CS) over the global ocean. They are obtained from the state-of-the-art Coupled Ocean–Atmosphere Response Experiment (COARE) bulk algorithm (version 3.0). Using the exchange coefficients from this bulk scheme, CD, CL, and CS are then expressed as simple polynomial functions of air–sea temperature difference (Ta − Ts)—where air temperature (Ta) is at 10 m, wind speed (Va) is at 10 m, and relative humidity (RH) is at the air–sea interface—to parameterize stability. The advantage of using polynomial-based exchange coefficients is that they do not require any iterations for stability. In addition, they agree with results from the COARE algorithm but at ≈5 times lower computation cost, an advantage that is particularly needed for ocean general circulation models (OGCMs) and climate models running at high horizontal resolution and short time steps. The effects of any water vapor flux in calculating the exchange coefficients are taken into account in the polynomial functions, a feature that is especially important at low wind speeds (e.g., Va < 5 m s−1) because air–sea mixing ratio difference can have a major effect on the stability, particularly in tropical regions. Analyses of exchange coefficients demonstrate the fact that water vapor can have substantial impact on air–sea exchange coefficients at low wind speeds. An example application of the exchange coefficients from the polynomial approach is the recalculation of climatological mean wind stress magnitude from 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) data in the North Pacific Ocean over 1979–2002. Using ECMWF 10-m winds and the authors’ methodology provides accurate surface stresses while largely eliminating the orographically induced Gibb’s waves found in the original ERA-40 surface wind stresses. These can have a large amplitude near mountainous regions and can extend far into the ocean interior. This study introduces exchange coefficients of air–sea fluxes, which are applicable to the wide range of conditions occurring over the global ocean, including the air–sea stability differences across the Gulf Stream and Kuroshio, regions which have been the subject of many climate model studies. This versatility results because CD, CL, and CS are determined for Va values of 1 to 40 m s−1, (Ta − Ts), intervals of −8° to 7°C, and RH values of 0% to 100%. Exchange coefficients presented here are called the Naval Research Laboratory (NRL) Air–Sea Exchange Coefficients (NASEC) and they are suitable for a wide range of air–sea interaction studies and model applications.
Monitoring the Reflectivity Calibration of a Scanning Radar Using a Profiling Radar and a Disdrometer
Authors: Williams Christopher R. , Gage Kenneth S. , Clark Wallace , Kucera Paul
Published: August 2005

This paper describes a method of absolutely calibrating and routinely monitoring the reflectivity calibration from a scanning weather radar using a vertically profiling radar that has been absolutely calibrated using a collocated surface disdrometer. The three instruments have different temporal and spatial resolutions, and the concept of upscaling is used to relate the small resolution volume disdrometer observations with the large resolution volume scanning radar observations. This study uses observations collected from a surface disdrometer, two profiling radars, and the National Weather Service (NWS) Weather Surveillance Radar-1988 Doppler (WSR-88D) scanning weather radar during the Texas–Florida Underflight-phase B (TEFLUN-B) ground validation field campaign held in central Florida during August and September 1998.

The statistics from the 2062 matched profiling and scanning radar observations during this 2-month period indicate that the WSR-88D radar had a reflectivity 0.7 dBZ higher than the disdrometer-calibrated profiler, the standard deviation was 2.4 dBZ, and the 95% confidence interval was 0.1 dBZ. This study implies that although there is large variability between individual matched observations, the precision of a series of observations is good, allowing meaningful comparisons useful for calibration and monitoring.
Damaging Surface Wind Mechanisms within the 10 June 2003 Saint Louis Bow Echo during BAMEX
Authors: Atkins Nolan T. , Bouchard Christopher S. , Przybylinski Ron W. , Trapp Robert J. , Schmocker Gary
Published: August 2005

Detailed radar and damage survey analyses of a severe bow echo event that occurred on 10 June 2003 during the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment are presented. A bow echo formed just east of Saint Louis, Missouri, and produced a continuous straight-line wind damage swath approximately 8 km in width and 50 km in length along with five F0–F1 tornadoes. Careful superposition of the damage survey analysis and Weather Surveillance Radar-1988 Doppler (WSR-88D) data from Saint Charles, Missouri (KLSX), showed that the primary straight-line wind damage swath was not collocated with the bow echo apex as has been suggested in previous studies. Rather, the primary damage swath was found north of the bow apex, collocated with a low-level vortex that formed on the leading edge of the bow echo. Much of the primary damage swath appeared to have been created by the low-level vortex. Moreover, most of the surface straight-line wind damage was generated during the early stages of bow echo morphology prior to when the radar-detected bow echo attributes were best defined.

Detailed analysis of the KLSX radar data revealed the genesis of 11 low-level meso-γ-scale vortices within the convective system. Superposition of the damage survey data showed that five of the vortices were tornadic. Careful analysis of the radar data suggests that it may be possible to distinguish between the tornadic and nontornadic vortices. Consistently, the tornadic vortices were longer-lived and stronger at low levels [0–3 km above ground level (AGL)] and rapidly deepened and intensified just prior to tornadogenesis. Similar evolution was not observed with the nontornadic vortices. All of the tornadic vortices formed coincident with or after the genesis time of the rear-inflow jet. These results suggest that the rear-inflow jet may be important for creating tornadic vortices within bow echoes. The detection and warning implications of these results are discussed.
Evaluation of Heavy Precipitation Forecasts Using Composite-Based Methods: A Distributions-Oriented Approach
Authors: Nachamkin Jason E. , Chen Sue , Schmidt Jerome
Published: August 2005

Numerical forecasts of heavy warm-season precipitation events are verified using simple composite collection techniques. Various sampling methods and statistical measures are employed to evaluate the general characteristics of the precipitation forecasts. High natural variability is investigated in terms of its effects on the relevance of the resultant statistics. Natural variability decreases the ability of a verification scheme to discriminate between systematic and random error. The effects of natural variability can be mitigated by compositing multiple events with similar properties. However, considerable sample variance is inevitable because of the extreme diversity of mesoscale precipitation structures.

The results indicate that forecasts of heavy precipitation were often correct in that heavy precipitation was observed relatively close to the predicted area. However, many heavy events were missed due in part to the poor prediction of convection. Targeted composites of the missed events indicate that a large percentage of the poor forecasts were dominated by convectively parameterized precipitation. Further results indicate that a systematic northward bias in the predicted precipitation maxima is related to the deficits in the prediction of subsynoptically forced convection.