bluuebunny/crossref_metadata_2025 huggingface dataset:
Patients' Knowledge about Risk Factors for Erectile Dysfunction is Poor
Authors: Baumgartner Martin K. , Hermanns Thomas , Cohen Aron , Schmid Daniel M. , Seifert Burkhardt , Sulser Tullio , Strebel Räto T.
Published: May 2008

Introduction

Well informed and educated patients ideally manage to prevent or delay the onset of severe chronic diseases. With respect to erectile dysfunction (ED) this is of importance because ED is considered to herald debilitating cardiovascular diseases like coronary artery disease.

Aim

This survey aimed to assess patient's knowledge about risk factors (RF) for ED and to identify their preferred source of information.

Main Outcome Measures

Knowledge of RF for ED and sources used to gather information about ED as reported by patients with ED.

Methods

Between July 2004 and June 2006, 126 patients who presented at our outpatient clinic for an assessment of their ED were prospectively evaluated. The patients received a questionnaire about their demographic and socioeconomic circumstances, their strategies to gather information about ED, and their knowledge of specific RF for this disease. The questionnaire was completed by 81 patients (64%).

Results

Forty-one patients (51%) could not name one single RF for ED. Three men knew more than three RF. The two most popular sources of information were the Internet and general practitioners. Well-educated patients were significantly better informed than others. Patients using the Internet as source for health information were significantly younger and had a better knowledge about RF for ED compared to those not using the Internet.

Conclusion

Patients' knowledge about RF for ED is poor. The Internet seems to be the most useful information source for patients with ED and is predominantly used by younger and better educated patients. Given that ED is considered to be a precursor lesion of severe cardiovascular diseases, patient information and education deserves more attention.
Putting Rubrics to the Test: The Effect of a Model, Criteria Generation, and Rubric‐Referenced Self‐Assessment on Elementary School Students' Writing
Authors: Andrade Heidi L. , Du Ying , Wang Xiaolei
Published: May 2008

The purpose of this study was to investigate the effect of reading a model written assignment, generating a list of criteria for the assignment, and self‐assessing according to a rubric, as well as gender, time spent writing, prior rubric use, and previous achievement on elementary school students' scores for a written assignment (N = 116). Participants were in grades 3 and 4. The treatment involved using a model paper to scaffold the process of generating a list of criteria for an effective story or essay, receiving a written rubric, and using the rubric to self‐assess first drafts. The comparison condition involved generating a list of criteria for an effective story or essay, and reviewing first drafts. Findings include a main effect of treatment and of previous achievement on total writing scores, as well as main effects on scores for the individual criteria on the rubric. The results suggest that using a model to generate criteria for an assignment and using a rubric for self‐assessment can help elementary school students produce more effective writing.
Instructional Tools in Educational Measurement and Statistics (ITEMS) for School Personnel: Evaluation of Three Web‐Based Training Modules
Authors: Zwick Rebecca , Sklar Jeffrey C. , Wakefield Graham , Hamilton Cris , Norman Alex , Folsom Douglas
Published: May 2008

In the current No Child Left Behind era, K‐12 teachers and principals are expected to have a sophisticated understanding of standardized test results, use them to improve instruction, and communicate them to others. The goal of our project, funded by the National Science Foundation, was to develop and evaluate three Web‐based instructional modules in educational measurement and statistics to help school personnel acquire the “assessment literacy” required for these roles. Our first module, “What's the Score?” was administered in 2005 to 113 educators who also completed an assessment literacy quiz. Viewing the module had a small but statistically significant positive effect on quiz scores. Our second module, “What Test Scores Do and Don't Tell Us,” administered in 2006 to 104 educators, was even more effective, primarily among teacher education students. In evaluating our third module, “What's the Difference?” we were able to recruit only 33 participants. Although those who saw the module before taking the quiz outperformed those who did not, results were not statistically significant. Now that the research phase is complete, all ITEMS instructional materials are freely available on our Website.
Site fidelity and association patterns in a deep‐water dolphin: Rough‐toothed dolphins (Steno bredanensis) in the Hawaiian Archipelago
Authors: Baird Robin W. , Webster Daniel L. , Mahaffy Sabre D. , McSweeney Daniel J. , Schorr Gregory S. , Ligon Allan D.
Published: May 2008

Abstract

In the Pacific, rough‐toothed dolphins (Steno bredanensis) are typically found in the open ocean and in deep waters around oceanic islands. We examined habitat use, site fidelity, movements, and association patterns of this species in the main Hawaiian Islands. Sighting rates were highest in depths >1,500 m. There were frequent within‐ and between‐year resightings off the island of Hawai'i, indicating a small population size with high site fidelity. Resighting rates were lower off Kaua'i/Ni'ihau, indicating a larger population size, but with some site fidelity. Two individuals were documented moving from Kaua'i to Hawai'i, a distance of 480 km, but were not seen to associate with dolphins off Hawai'i. Observed movements were consistent with at most 2% dispersal per year between these two areas. Differences in group sizes, habitat use, and behavior imply that movements among the islands may be limited. Little is known about the diet of rough‐toothed dolphins in Hawai'i, but they are thought to feed primarily on near‐surface species. High fidelity to deep‐water areas off the island of Hawai'i likely reflects an increase in the predictability of prey associated with upwelling due to the island mass effect, wind stress curl and cyclonic eddies that form off the island.
Substantial Archaeocortical Atrophy and Neuronal Loss in Multiple Sclerosis
Authors: Papadopoulos Dimitrios , Dukes Sumayya , Patel Ryan , Nicholas Richard , Vora Abhilash , Reynolds Richard
Published: May 2008

Recent studies have revealed extensive neocortical pathology in multiple sclerosis (MS). The hippocampus is a unique archaeocortical structure understudied in MS. It plays a central role in episodic and anterograde memory—the most frequently impaired cognitive modalities in MS. This histopathological study aimed to investigate inflammatory demyelination and neurodegenerative changes in the MS archaeocortex. A detailed quantitative analysis was performed on hippocampal autopsy tissue from 45 progressive MS cases and seven controls. Forty‐one lesions were identified in 28 of the 45 hippocampal MS‐blocks examined, with percentage area of demyelination averaging 30.4%. The majority of lesions were chronic and subpially or subependymally located. Compared to controls, neuronal numbers were decreased by 27% in CA1 and 29.7% in CA3‐2. Furthermore, the size of neurones was decreased by 17.4% in CA1. There was evidence of gross hippocampal atrophy with a 22.3% reduction in the average cross‐sectional area, which correlated with neuronal loss. Our study provides evidence of substantial archaeocortical pathology largely resembling patterns seen in the neocortex and suggests that hippocampal involvement could contribute to memory impairments often seen in MS.
Involvement of Electron Transfer in the Photoreaction of Zebrafish Cryptochrome‐DASH†
Authors: Zikihara Kazunori , Ishikawa Tomoko , Todo Takeshi , Tokutomi Satoru
Published: May 2008

Photoreaction of a blue‐light photoreceptor Cryptochrome‐DASH (Cry‐DASH), a new member of the Cryptochrome family, from zebrafish was studied by UV–visible absorption spectroscopy in aqueous solutions at 293 K. Zebrafish Cry‐DASH binds two chromophores, a flavin adenine dinucleotide (FAD) and a N5,N10‐methenyl‐5,6,7,8‐tetrahydrofolate (MTHF) noncovalently. The bound FAD exists in the oxidized form (FADox) in the dark. Blue light converts FADox to the neutral radical form (FADH?). Formed FADH? is transformed to the fully reduced form FADH2 (or FADH−) by successive light irradiation, or reverts to FADox. FADH2 (or FADH−) reverts to FADH? or possibly to FADox directly. The effect of dithiothreitol suggests a possible electron transfer between FAD in zebrafish Cry‐DASH and reductants in the external medium. This is the first report on the photoreaction pathway and kinetics of a vertebrate Cry‐DASH family protein.
The Photosensitizing Potential of Compact Fluorescent vs Incandescent Light Bulbs
Authors: Chignell Colin F. , Sik Robert H. , Bilski Piotr J.
Published: May 2008

Recently an article about the new energy‐saving compact fluorescent light (CFL) bulbs appeared in Parade magazine [Rosenfeld, I. (2008) ParadeFeb 3, 22]. Under the heading “Bright Lights, Bad Headache?” the writer states that “new research suggests some dangers” involving these lights because they are fluorescent and “can aggravate skin rashes in people with lups, eczema, dermatitis or porphyria.” We measured the emission spectrum of a 14 W compact fluorescent bulb (with the same luminous flux as a 60 W incandescent bulb) and compared it to 60 W soft white incandescent and cool white fluorescent (CWF) bulbs. Our results clearly show that the spectral irradiance of the compact fluorescent bulb is similar to that of the CWF bulb; both exhibit sharp Hg emission lines at 365 nm (very weak), 404 nm (weak), 435 nm (moderate) and 543 nm (strong). In contrast, the emission of the incandescent bulb begins at 375 nm and then increases monotonically to above 750 nm. From their respective absorption spectra we calculated the potential photosensitization indices of protoporphyrin IX (PPIX; a prototypic porphyria skin photosensitizer) and riboflavin (a putative lens photosensitizer) vs 14 W compact fluorescent, CWF and 60 W incandescent bulbs. A higher photosensitization index would indicate a greater chance that the light/photosensitizer combination would cause photosensitization of the skin or eyes. We found that for PPIX and riboflavin the photosensitization index of the compact fluorescent bulb is less than half that of the 60 W incandescent bulb. These results suggest that substitution of a compact fluorescent bulb for an incandescent bulb of the same luminous flux should not increase the phototoxicity of skin porphyrins or lens riboflavin.
Measurement of Ultraviolet Exposure in Epidemiological Studies of Skin and Skin Cancers
Authors: Worswick Scott Drayton , Cockburn Myles , Peng David
Published: May 2008

As our understanding of the role of UV in causing skin cancer continues to expand, researchers and clinicians must continue to remain up to date on the various means by which UV exposure can be quantified. The purpose of this article was to review the current methods used to measure lifetime exposure to UV and to summarize the strengths and weaknesses of each of these approaches. Thus we include here a review of research articles that deal with questionnaire reliability and physical examination. We also review more technologically advanced techniques used to measure chronic UV exposure; these include microtopography, histology, gene studies and spectroscopy. Both the utility of using a specific measurement technique and the accuracy of particular techniques are explored. Finally, we touch upon the results of articles that link UV exposure to skin cancer and what this means for the future of UV‐induced skin cancer research.
Self‐application of single‐use eyedrop containers in an elderly population: comparisons with standard eyedrop bottle and with younger patients
Authors: Dietlein Thomas S. , Jordan Jens F. , Lüke Christoph , Schild Andrea , Dinslage Sven , Krieglstein Guenter K.
Published: May 2008

Purpose:  To test whether patients aged ≥80 years can safely and successfully apply eyedrops from a single‐use eyedrop container without support, and to compare the results with those of younger patients using single‐use containers and older patients using standard eyedrop bottles.

Methods:  Patients aged ≥80 years who had no physical or mental conditions hindering self‐application of eyedrops and actually did so because of glaucoma or dry eyes were included consecutively in the study group (n = 44) in order to perform self‐application of eyedrops from single‐use eyedrop containers. Patients were observed meticulously by two investigators, who documented practical problems during the procedure in a checklist. In control group A (n = 22), glaucoma or sicca patients aged between 50 and 65 years applied drops from single‐use eyedrop containers; in control group B (n = 28), glaucoma or sicca patients aged ≥80 years used a traditional eyedrop bottle.

Results:  Successful application of the drops into the conjunctival sac was achieved by 57% in the study group (95% and 89% in control groups A and B, respectively). Scratching of the eyedrop container along the conjunctiva or cornea was observed in 68% of the study group (41% and 61% in control groups A and B, respectively). Frequency of problems during opening and self‐application of single‐use eyedrop containers in the study group showed an inverse correlation to visual acuity in the better eye and previous experience with this kind of eyedrop container.

Conclusion:  Older patients have massive problems in self‐administering eyedrops from single‐use containers. Factors influencing the success of self‐application may include the patient’s previous experience with this kind of eyedrop container and the patient’s visual acuity.
Epidemiology of aniridia in Sweden and Norway
Authors: Edén Ulla , Iggman David , Riise Ruth , Tornqvist Kristina
Published: May 2008

Purpose:  To investigate the epidemiology of aniridia in the populations of Sweden and Norway.

Methods:  A thorough search for aniridia patients has been performed in Sweden and Norway. All participants had a clinical ophthalmological examination documented through photography. Blood samples were taken for mutation analysis and pedigrees were established.

Results:  A total of 181 patients with aniridia were identified in the two countries. This gives an age‐specific prevalence of 1:72 000 in the entire region, 1:70 000 in Sweden and 1:76 000 in Norway. A total of 124 individuals (69%) were examined. Male/female ratio was 0.94 (Sweden 0.85 and Norway 1.2). Mean age of the examined patients was 29 years and median age 25 years. We did not find any significant age difference between the two countries. The mean visual acuity (VA) was 0.19 (Sweden 0.19 and Norway 0.18).The number of families with more than one affected member was 31 and the number of sporadic cases was 40.

Conclusion:  We have done a thorough search of the literature, but we have found no earlier studies describing aniridia in an entire country and only a few reports from larger areas. We assume that most aniridia patients have been found and the aniridia prevalence of 1:72 000 can be regarded as well supported. Further studies on other aspects of aniridia are in progress, and information from these can contribute to guidelines for the care of patients with this rare but serious disease.
First Molecular Characterization of Group B Streptococci with Reduced Penicillin Susceptibility
Authors: Kimura Kouji , Suzuki Satowa , Wachino Jun-ichi , Kurokawa Hiroshi , Yamane Kunikazu , Shibata Naohiro , Nagano Noriyuki , Kato Haru , Shibayama Keigo , Arakawa Yoshichika
Published: May 2008

Group B streptococci (GBS;
Streptococcus agalactiae
) are the leading cause of neonatal invasive diseases and are also important pathogens for adults. Penicillins are the drugs of first choice for the treatment of GBS infections, since GBS have been regarded to be uniformly susceptible to penicillins so far. Here we characterize the first strains of GBS with reduced penicillin susceptibility (PRGBS) identified in Japan. Fourteen PRGBS strains were clinically isolated from the sputa of elderly patients from 1995 to 2005; and the MICs of penicillin, oxacillin, and ceftizoxime ranged from 0.25 to 1 μg/ml, 2 to 8 μg/ml, and 4 to 128 μg/ml, respectively. Moreover, some strains were also insusceptible to ampicillin, cefazolin, cefepime, and cefotaxime. All the PRGBS isolates tested possessed a few amino acid substitutions adjacent to the conserved SSN and KSG motifs (amino acids 402 to 404 and 552 to 554, respectively) of PBP 2X, and the amino acid substitutions could be classified into two types, Q557E and V405A. Western blotting analysis of the 14 clinical isolates with anti-PBP 2X-specific serum suggested that the amount of PBP 2X among the 14 PRGBS isolates was reduced, although the 2 ATCC strains produced a significant amount of PBP 2X. The introduction of PRGBS-derived PBP 2X genes into penicillin-susceptible strains through allelic exchange elevated their penicillin insusceptibility, suggesting that these altered PBP 2X genes are responsible for the penicillin insusceptibility in PRGBS strains. In this study, we characterized for the first time PRGBS strains on a molecular basis, although several reports have so far mentioned the existence of β-lactam-insusceptible GBS from a phenotypic standpoint.
Differential Expression of the Smb Bacteriocin in
Streptococcus mutans
Isolates
Authors: Yonezawa Hideo , Kuramitsu Howard K. , Nakayama Shu-ichi , Mitobe Jiro , Motegi Mizuho , Nakao Ryoma , Watanabe Haruo , Senpuku Hidenobu
Published: May 2008

The two-component lantibiotic Smb is produced by
Streptococcus mutans
GS5. In the present study, we identified seven strains of
S. mutans
containing the
smb
gene cluster. These strains could be classified into high- and low-level Smb producers relative to the levels of Smb production by indicator strains in vitro. This classification was dependent upon the transcription levels of the structural
smbA
and
smbB
genes. Sequence analysis upstream of
smbA
in the high- and low-level Smb-producing strains revealed differences at nucleotide position −46 relative to the
smbA
start codon. Interestingly, the transcription start site was present upstream of the point mutation, indicating that both groups of strains have the same promoter constructs and that the differential expression of
smbA
and
smbB
mRNA occurred subsequent to transcription initiation. In addition,
smbA
::
lacZ
fusion expression was higher when it was regulated by the sequences of strains with high-level Smb activity than when it was regulated by the comparable region from strains with low-level Smb activity. Taken together, we conclude that high- or low-level Smb expression is dependent on the presence of a G or a T nucleotide at position −46 relative to the
smbA
translational start site in
S. mutans
Smb producers.
Postantibiotic Effects and Bactericidal Activities of Levofloxacin and Gatifloxacin at Concentrations Simulating Those of Topical Ophthalmic Administration against Fluoroquinolone-Resistant and Fluoroquinolone-Sensitive Methicillin-Resistant
Staphylococcus aureus
Strains
Authors: Hoshi Saichi , Kikuchi Ken , Sasaki Takashi , Sotozono Chie , Kinoshita Shigeru , Hiramatsu Keiichi
Published: May 2008

The bactericidal activities and postantibiotic effects (PAEs) of levofloxacin and gatifloxacin at concentrations corresponding to those in antibiotic eye drops against methicillin-resistant
Staphylococcus aureus
strains were determined. Levofloxacin and gatifloxacin at concentrations simulating those in eye drops showed lower bactericidal activities and shorter PAEs against fluoroquinolone-resistant strains than against fluoroquinolone-sensitive strains.
Evaluation of Antibiotic Therapy for Eradication of “
Candidatus
Helicobacter heilmannii”
Authors: Matsui Hidenori , Aikawa Chihiro , Sekiya Yukie , Takahashi Shinichi , Murayama Somay Yamagata , Nakamura Masahiko
Published: May 2008

Triple-agent therapy with lansoprazole (15 mg/kg)-clarithromycin (50 mg/kg)-amoxicillin (50 mg/kg) twice daily for 7 days fully cleared “
Candidatus
Helicobacter heilmannii” from infected mouse stomachs. Moreover, gastric mucosa-associated lymphoid tissue lymphoma-like lesions in the stomach nearly disappeared in the treated mice 4 months after the therapy.
Differential Activation of Human and Mouse Toll-Like Receptor 4 by the Adjuvant Candidate LpxL1 ofNeisseria meningitidis
Authors: Steeghs Liana , Keestra A. Marijke , van Mourik Andries , Uronen-Hansson Heli , van der Ley Peter , Callard Robin , Klein Nigel , van Putten Jos P. M.
Published: May 2008

Neisseria meningitidisLpxL1 lipopolysaccharide (LPS) bearing penta-acylated lipid A is considered a promising adjuvant candidate for inclusion in futureN. meningitidisvaccines, as it elicits a markedly reduced endotoxic response in human macrophages relative to that in wild-type (hexa-acylated) LPS, while it is an equally effective adjuvant in mice. As dendritic cells (DC) and Toll-like receptors (TLR) are regarded as central mediators in the initiation of an immune response, here we evaluated the ability of LpxL1 LPS to mature and to activate human DC and examined its TLR4-/MD-2-activating properties. Unexpectedly, purified LpxL1 LPS displayed minimal human DC-stimulating properties compared to wild-type LPS. Although whole bacteria induced DC maturation and activation irrespective of their type of LPS, the LpxL1 mutant failed to activate the human recombinant TLR4/MD-2 complex expressed in HeLa cells. Similarly, purified LpxL1 LPS was unable to activate human TLR4/MD-2 and it even acted as an antagonist of wild-type LPS. Both wild-type and LpxL1 LPSs activated the murine TLR4/MD-2 complex, consistent with their abilities to induce maturation and activation of murine DC. Assays with cells transfected with different combinations of human and murine TLR4 and MD-2 indicated that TLR4 was a more-major determinant of the LPS response than MD-2. The species-specific activation of the TLR4/MD-2 complex by LpxL1 LPS may have an impact on the use of LpxL1 LPS as an adjuvant and the use of murine immunization models in human meningococcal vaccine development.
Proteomic Analysis of and Immune Responses toEhrlichia chaffeensisLipoproteins
Authors: Huang Haibin , Lin Mingqun , Wang Xueqi , Kikuchi Takane , Mottaz Heather , Norbeck Angela , Rikihisa Yasuko
Published: May 2008

Ehrlichia chaffeensisis an obligately intracellular gram-negative bacterium and is the etiologic agent of human monocytic ehrlichiosis (HME). AlthoughE. chaffeensisinduces the generation of several cytokines and chemokines by leukocytes,E. chaffeensislacks lipopolysaccharide and peptidoglycan. Bioinfomatic analysis of theE. chaffeensisgenome, however, predicted genes encoding 15 lipoproteins and 3 posttranslational lipoprotein-processing enzymes. The present study showed that by use of multidimensional liquid chromatography followed by tandem mass spectrometry, all predicted lipoproteins as well as lipoprotein-processing enzymes were expressed byE. chaffeensiscultured in the human promyelocytic leukemia cell line HL-60. Consistent with this observation, a signal peptidase II inhibitor, globomycin, was found to inhibitE. chaffeensisinfection and lipoprotein processing in HL-60 cell culture. To study in vivoE. chaffeensislipoprotein expression and host immune responses toE. chaffeensislipoproteins, 13E. chaffeensislipoprotein genes were cloned into a mammalian expression vector. When the DNA constructs were inoculated into naïve dogs, or when dogs were infected withE. chaffeensis, the animals developed delayed-type hypersensitivity reactions at cutaneous sites of the DNA construct deposition and serum antibodies to these lipoproteins. This is the first demonstration of lipoprotein expression and elicitation of immune responses by a member of the orderRickettsiales. Multiple lipoproteins expressed byE. chaffeensisin vitro and in vivo may play key roles in pathogenesis and immune responses in HME.
The Absence of Toll-Like Receptor 4 Signaling in C3H/HeJ Mice Predisposes Them to Overwhelming Rickettsial Infection and Decreased Protective Th1 Responses
Authors: Jordan Jeffrey M. , Woods Michael E. , Olano Juan , Walker David H.
Published: May 2008

The importance of toll-like receptor 4 (TLR4) in immunity to rickettsiae remains elusive. To investigate the role of TLR4 in protection against rickettsioses, we utilized C3H/HeJ mice, which are naturally defective in TLR4 signaling, and compared the responses of C3H/HeN and C3H/HeJ mice following intravenous inoculation withRickettsia conorii. Mice genetically defective in TLR4 signaling developed overwhelming, fatal rickettsial infections when given an inoculum that was nonfatal for TLR4-competent mice. In addition, mice lacking the ability to signal through TLR4 had significantly greater rickettsial burdens in vivo. Moreover, we observed greater concentrations of the cytokines interleukin 6 (IL-6), tumor necrosis factor alpha, IL-12p40, IL-12p70, and IL-17 in the sera of mice with intact TLR4 function as well as significantly greater quantities of activated CD4+and CD8+T lymphocytes. Additionally, we also observed that Th17 cells were present only in TLR4-competent mice, suggesting an important role for TLR4 ligation in the activation of this subset. In agreement with these data, we also observed significantly greater percentages of immunosuppressive regulatory T cells in the spleen during infection in TLR4-defective mice. Together, these data demonstrate that, while rickettsiae do not contain endotoxic lipopolysaccharide, they nevertheless initiate TLR4-specific immune responses, and these responses are important in protection.
CcpA-Mediated Repression of Streptolysin S Expression and Virulence in the Group A Streptococcus
Authors: Kinkel Traci L. , McIver Kevin S.
Published: May 2008

CcpA is the global mediator of carbon catabolite repression (CCR) in gram-positive bacteria, and growing evidence from several pathogens, including the group A streptococcus (GAS), suggests that CcpA plays an important role in virulence gene regulation. In this study, a deletion of
ccpA
in an invasive M1 GAS strain was used to test the contribution of CcpA to pathogenesis in mice. Surprisingly, the Δ
ccpA
mutant exhibited a dramatic “hypervirulent” phenotype compared to the parental MGAS5005 strain, reflected as increased lethality in a model of systemic infection (intraperitoneal administration) and larger lesion size in a model of skin infection (subcutaneous administration). Expression of
ccpA
in
trans
from its native promoter was able to complement both phenotypes, suggesting that CcpA acts to repress virulence in GAS. To identify the CcpA-regulated gene(s) involved, a transcriptome analysis was performed on mid-logarithmic-phase cells grown in rich medium. CcpA was found to primarily repress 6% of the GAS genome (124 genes), including genes involved in sugar metabolism, transcriptional regulation, and virulence. Notably, the entire
sag
operon necessary for streptolysin S (SLS) production was under CcpA-mediated CCR, as was SLS hemolytic activity. Purified CcpA-His bound specifically to a
cre
within
sagAp
, demonstrating direct repression of the operon. Finally, SLS activity is required for the increased virulence of a Δ
ccpA
mutant during systemic infection but did not affect virulence in a wild-type background. Thus, CcpA acts to repress SLS activity and virulence during systemic infection in mice, revealing an important link between carbon metabolism and GAS pathogenesis.
Cathelicidin LL-37 in Severe
Streptococcus pyogenes
Soft Tissue Infections in Humans
Authors: Johansson Linda , Thulin Pontus , Sendi Parham , Hertzén Erika , Linder Adam , Åkesson Per , Low Donald E. , Agerberth Birgitta , Norrby-Teglund Anna
Published: May 2008

Severe soft tissue infections, such as necrotizing fasciitis and severe cellulitis, caused by group A streptococci (GAS) are rapidly progressing life-threatening infections characterized by massive bacterial loads in the tissue even late after the onset of infection. Antimicrobial peptides are important components of the innate host defense, and cathelicidins have been shown to protect against murine necrotic skin infections caused by GAS. However, it has been demonstrated that the streptococcal cysteine protease SpeB proteolytically inactivates the human cathelicidin LL-37 in vitro. Here we have investigated the expression of LL-37 and its interaction with GAS and SpeB during acute severe soft tissue infections by analyses of patient tissue biopsy specimens. The results showed large amounts of LL-37, both the proform (hCAP18) and the mature peptide, in the tissue. Confocal microscopy identified neutrophils as the main source of the peptide. A distinct colocalization between the bacteria and LL-37 could be noted, and bacterial loads showed positive correlation to the LL-37 levels. Areas with high LL-37 levels coincided with areas with large amounts of SpeB. Confocal microscopy confirmed strong colocalization of GAS, SpeB, and LL-37 at the bacterial surface. Taken together, the findings of this study provide in vivo support of the hypothesis that SpeB-mediated inactivation of LL-37 at the streptococcal surface represents a bacterial resistance mechanism at the infected tissue site in patients with severe GAS tissue infections.
Aspergillus fumigatus
Stimulates Leukocyte Adhesion Molecules and Cytokine Production by Endothelial Cells In Vitro and during Invasive Pulmonary Disease
Authors: Chiang Lisa Y. , Sheppard Donald C. , Gravelat Fabrice N. , Patterson Thomas F. , Filler Scott G.
Published: May 2008

Invasive aspergillosis is characterized by hyphal invasion of the blood vessels, which contributes to the pathogenesis of this disease. During this angioinvasion,
Aspergillus fumigatus
interacts with the endothelial cell lining of the blood vessels. We investigated the response of vascular endothelial cells to
A. fumigatus
infection in vitro and in mouse models of invasive pulmonary aspergillosis. Infection with hyphae, but not with conidia, stimulated endothelial cells to synthesize E-selectin, vascular cell adhesion molecule 1 (VCAM-1), interleukin 8, and tumor necrosis factor alpha (TNF-α) in vitro. Killed hyphae induced approximately 40% less stimulation than did live hyphae. Endothelial cell stimulation required contact between the hyphae and endothelial cells but not endocytosis of the organisms. Studies with Δ
gliP
and Δ
stuA
null mutants of
A. fumigatus
indicated that the extent of endothelial cell stimulation was not influenced by gliotoxin or other StuA-dependent factors synthesized by
A. fumigatus
. In neutropenic mice infected with wild-type
A. fumigatus
, increased pulmonary expression of E-selectin, cytokine-induced neutrophil chemoattractant (KC), and TNF-α occurred only when neutropenia had resolved. In nonneutropenic mice immunosuppressed with corticosteroids,
A. fumigatus
stimulated earlier pulmonary expression of E-selectin, VCAM-1, and KC, while expression of intercellular adhesion molecule 1 and TNF-α was suppressed. In both mouse models, expression of E-selectin and KC was associated with high pulmonary fungal burden, angioinvasion, and neutrophil adherence to endothelial cells. Therefore, the expression of leukocyte adhesion molecules and secretion of proinflammatory cytokines by endothelial cells in response to
A. fumigatus
could enhance the host defense against this organism by contributing to the recruitment of activated leukocytes to sites of angioinvasion.
Epidermal Growth Factor Inhibits
Campylobacter jejuni
-Induced Claudin-4 Disruption, Loss of Epithelial Barrier Function, and
Escherichia coli
Translocation
Authors: Lamb-Rosteski Jennifer M. , Kalischuk Lisa D. , Inglis G. Douglas , Buret Andre G.
Published: May 2008

Campylobacter jejuni
is a leading cause of acute bacterial enteritis in humans. Poultry serves as a major reservoir of
C. jejuni
and is thought to act as a principal vehicle of transmission to humans. Epidermal growth factor (EGF) is a small amino acid peptide that exerts a broad range of activities on the intestinal epithelium. The aims of this study were to determine the effect of EGF on
C. jejuni
intestinal colonization in newly hatched chicks and to characterize its effects on
C. jejuni
-induced intestinal epithelial barrier disruption. White Leghorn chicks were treated with EGF daily, starting 1 day prior to
C. jejuni
infection, and were compared to control and
C. jejuni
-infected, EGF-treated chicks. Infected chicks shed
C. jejuni
in their feces throughout the study period.
C. jejuni
colonized the small intestine and cecum, disseminated to extraintestinal organs, and caused jejunal villus atrophy. EGF reduced jejunal colonization and dissemination of
C. jejuni
to the liver and spleen. In EGF-treated
C. jejuni
-infected chicks, villus height was not significantly different from that in untreated
C. jejuni
-infected chicks or controls. In vitro,
C. jejuni
attached to and invaded intestinal epithelial cells, disrupted tight junctional claudin-4, and increased transepithelial permeability.
C. jejuni
also promoted the translocation of noninvasive
Escherichia coli
C25. These
C. jejuni
-induced epithelial abnormalities were abolished by pretreatment with EGF, and the effect was dependent upon activation of the EGF receptor. These findings highlight EGF's ability to alter colonization of
C. jejuni
in the intestinal tract and to protect against pathogen-induced barrier defects.
Assessment of the Importance of Nutrient Recycling by Seabirds in the St. Lawrence Estuary
Authors: Bédard J. , Therriault J. C. , Bérubé J.
Published: May 2008

Feeding and excretion rates of the herring, great black-backed, and ring-billed gulls (Larus argentatus, L. marinus, and L. delawarensis), and of the common eider (Somateria mollissima) were measured in captive individuals and the concentration of soluble nutrients in their excreta was established.The bird population in a 30.6-km2 coastal study area varied between 2500 and 12 500 individuals between early May and mid-November. These birds excreted a seasonal total of 5.8, 4.2, and 48.1 kg-at. of soluble silicate, phosphate, and nitrogenous compounds, respectively. Such quantities, when introduced in the nutrient budget of the coastal area studied, are found to be negligible, considering the levels of nutrients generally recorded in these waters on the one hand, and the relative importance of alternate sources such as land drainage and vertical mixing on the other. Thus, the seabirds can hardly be viewed, except perhaps under the most special circumstances, as important agents in the dynamic nutrient regeneration processes of marine coastal waters of the St. Lawrence Estuary.Key words: nutrient recycling, seabirds, St. Lawrence Estuary
Nutrient Distributions in the Canadian Archipelago: Indicators of Summer Water Mass and Flow Characteristics
Authors: Jones E. P. , Coote A. R.
Published: May 2008

Concentrations of the nutrients, phosphate, nitrate, and silicate, were measured at several locations in Lancaster Sound, Jones Sound, and Smith Sound. Arctic Ocean surface layer water flowing out through Lancaster Sound and Jones Sound have higher phosphate and silicate concentrations than that flowing out through Smith Sound. Phosphate and silicate concentrations can be useful to indicate flow patterns within some regions of the Canadian Archipelago and to delineate partially the gyre in the Canadian Basin of the Arctic Ocean.Key words: nutrients: phosphate, nitrate, silicate; distribution: Arctic, Canadian Archipelago; water mass, identification, mixing
Influence of Size, Growth Rate, and Photoperiod on Cyclic Changes in Gill (Na + K)–ATPase Activity in Chinook Salmon (Oncorhynchus tshawytscha)
Authors: Ewing R. D. , Pribble H. J. , Johnson S. L. , Fustish C. A. , Diamond J. , Lichatowich J. A.
Published: May 2008

Juvenile spring chinook salmon (Oncorhynchus tshawytscha) (Rogue River stock) were reared in constant 8 °C well water under artificial lighting with photoperiods adjusted to Medford, Oregon. Juveniles were divided into six groups according to the amount of food provided. Growth (change in fork length per day) was linear from July through December for all six groups. Three distinct patterns of gill (Na + K)–ATPase activity were observed in these groups. In the two groups fed the largest rations, a peak in activity in October was observed with a smaller peak in July. Fish fed the smallest rations showed no increase in gill (Na + K)–ATPase activity throughout the year. At intermediate rations, there was a small peak in July but no peak in October. A growth rate of less than 0.027 cm/d appeared to suppress the October peak in gill (Na + K)–ATPase activity. Fish with higher growth rates showed peaks in activity in either October or NovemberKey words: chinook salmon, (Na + K)–ATPase, growth, photoperiod, Oncorhynchus tshawytscha
Insect Community Structure as an Index of Heavy-Metal Pollution in Lotic Ecosystems
Authors: Winner R. W. , Boesel M. W. , Farrell M. P.
Published: May 2008

Data from two streams suggest that macroinvertebrate community structure exhibits a predictable, graded response to heavy-metal pollution. In the more heavily stressed sections of both streams, macroinvertebrates, other than tubificid worms and chironomids, were virtually eliminated from rock-rubble, riffle habitats. Midge larvae comprised 75 to 86% of all insects collected from the most grossly polluted stations and less than 10% of the insect communities at the least polluted stations. The correlation coefficient for percentage of chironomids in relation to copper concentration was +0.93 (P ≤ 0.01). Changes in the coefficient of variation (CV) of percentage of chironomids per sample exhibited a consistent pattern. The lowest CV was at the most polluted stations and the CV increased along a gradient of decreasing metal concentrations, reaching maximum values at the least polluted stations. The number of species of chironomids was inversely related to the proportional density of the family in samples. In Elam's Run, the number of species of chironomids identified in samples increased from 15 at the most polluted station to 39 at the least polluted stations. Fifty-seven species of midges were collected along the 3-km stretch of this grossly polluted stream. Caddisflies were numerically important at the intermediately polluted stations in both streams. Mayflies occurred only at the least polluted stations. We hypothesize that heavily polluted habitats are dominated by midges, moderately polluted habitats by midges and caddisflies, and minimally polluted or unpolluted habitats by caddisflies and mayflies. Since there appears to be a direct relationship between the fraction of a community composed of chironomids and the degree of pollution, we suggest that the percentage of chironomids in samples may be a useful index of heavy-metal pollution.Key words: heavy metals, stream pollution, chironomids, aquatic insects
Seasonal Factors Affecting Buoyancy Attained in Still Water and Current by Fathead Minnows, Pimephales promelas
Authors: Luoma Maire E. , Gee John H.
Published: May 2008

This study investigated effects of various seasonal factors on buoyancy attained by fathead minnows, Pimephales promelas. Fish were taken from the field to the laboratory at regular intervals (when possible) over 2 yr, and buoyancy attained in either still water or current was measured. Buoyancy attained in still water and in current (maximum tolerable velocity) varied seasonally when fish were held and tested at a natural photoperiod and temperature of capture. Seasonal variation still occurred when fish were held and tested at a natural photoperiod but at 15 °C, and for those in current, at a velocity of 35 cm∙s−1. There was no seasonal variation in buoyancy attained by fish held in the laboratory under constant environmental conditions. Effects of photoperiod, sex, gonad development, estimated fat content, and condition of the fish on buoyancy were determined. Fish exposed to a photoperiod of 12 h illumination were less buoyant in still water and current than those held under longer or shorter photoperiods. There was no significant difference in buoyancy attained between females and males. However, buoyancy decreased significantly, especially in current, as gonad development increased. Buoyancy increased significantly in still water and in current with days of starvation. As coefficient of condition decreased, buoyancy increased significantly in current but not in still water. Estimated fat content, determined by a densitometric method, had no significant effect on buoyancy. Seasonal variation occurs in the ability to attain a particular buoyancy and this is influenced by a number of potentially interacting factors that include water temperature and velocity, photoperiod, gonad development, age, and condition of the fish.Key words: fathead minnow, Pimephales promelas, buoyancy, seasonal variation, photoperiod, condition of fish, gonad development
BIONESS, a New Design in Multiple Net Zooplankton Samplers
Authors: Sameoto D. D. , Jaroszynski L. O. , Fraser W. B.
Published: May 2008

BIONESS (Bedford Institute of Oceanography Net and Environmental Sampling System), a new multiple-net zooplankton and micronekton sampler, uses a new design concept with the nets arranged horizontally rather than vertically as in earlier multiple-net samplers. Ten 1.0-m2 nets open sequentially and are towed at 3 knots on a conductor cable that transmits and receives information between the ship and sampler. On the sampler are sensors for temperature, conductivity, depth, illumination, pitch, roll and yaw, and net closure together with internal and external flowmeters and a 35-mm camera equipped with a strobe light. This system can collect biological samples and environmental data simultaneously and photograph animals in front of the sampler.Key words: samplers, zooplankton, micronekton, instrumentation, photography, data collection, design
Multivariate Analysis of Meristic Characters of Capelin (Mallotus villosus) in the Northwest Atlantic
Authors: Carscadden J. E. , Misra R. K.
Published: May 2008

Counts were made on 11 meristic characters of mature male capelin. The Bonferroni method identified three characters that exhibited significant annual differences. Interpopulation differences were compared using the remaining eight characters, and three capelin stocks were identified. Other studies have tentatively identified at least four stocks, and based on this analysis, meristic characters show only limited promise in separating capelin stocks in the Northwest Atlantic. However, the sequence of statistical procedures used in this study offers potential in other stock discrimination studies.Key words: capelin, Mallotus villosus; meristics, multivariate analyses, Bonferroni method, discriminant function
Modified Dimethyl Sulfoxide (DMSO) Extraction for Chlorophyll Analysis of Phytoplankton
Authors: Burnison B. K.
Published: May 2008

This new extraction procedure eliminates the need for grinding glass fiber filters by heating the filter in DMSO (4 mL) for 10 min at 65 °C and subsequently filtering or centrifuging the sample after dilution with 90% acetone (6 mL). Scenedesmus and Selenastrum species gave about 20% higher concentrations of chlorophyll a using this method as compared to the standard 90% acetone procedure or grinding in DMSO only. The difference between heated DMSO and 90% acetone was reduced when natural phytoplankton were analyzed.Key words: chlorophyll, Chlorophyta, dimethyl sulfoxide, acetone, extraction
Accumulation of 14C Labeled Benzene and Related Compounds in the Rotifer Brachionus plicatilis from Seawater
Authors: Echeverria Tina
Published: May 2008

Rotifers were exposed to (1) a single dose of 14C labeled benzene on day 1 with initial concentrations of benzene at 0.1 and 1.0 μL/L declining over time and (2) a chronic exposure of 0.1 and 1.0 μL/L daily for 9 d. Both conditions resulted in rotifers accumulating 1000 to 10 000 times the 14C activity detected in the seawater. These concentrations were maintained in the rotifers for 8 and 11 d, respectively, and remained high even after exposure was terminated. Analysis of 14C activity from 14C labeled benzene detected in the water revealed its source to be phenolic compounds, compounds with a potentially higher toxicity than benzene. The water maintained a low level of 14C compounds throughout the experiments. Rotifers accumulated high quantities and retained most of the acquired 14C compounds after 2 d in clean water.Key words: benzene, rotifer, zooplankton, biomagnification
A Standardized Model of Experimental Furunculosis in Rainbow Trout (Salmo gairdneri)
Authors: Michel C.
Published: May 2008

With the aid of published information, we have developed a standardized and reproducible experimental model of furunculosis in rainbow trout (Salmo gairdneri). The infective doses (LD50 = 200 to 2000 germs, i.m.) employed strains of Aeromonas salmonicida, the virulence of which was maintained by passage in 15-g fingerlings. The number of viable cells in the dose was conveniently determined using the drop-plate enumeration technique; however, meaningful cell counts could only be obtained if broth cultures used for infecting the fish were harvested early in the exponential growth phase (OD < 1.000 at 525 nm). Better results were obtained with intramuscular injection than with intraperitoneal injection. The infection procedure involved injecting a dose of 10 LD50, intramuscularly, into each of 30 fish held at 15 °C and recording the mortalities for 10 d. Protection tests in which Tribrissen (28 mg sulfadiazine and 5.6 mg trimethoprim/kg fish for 8 d) was fed or tetracycline (1 mg per fish) i.m. injected into the infected fish served to demonstrate the value of the model. Results were in agreement with field observations with no death for treated fish and a mortality of 96%, for untreated fish. Key wordss rainbow trout, Salmo gairdneri; Aeromonas salmonicida, furunculosis, experimental infection
The Conundrum of the Stock Concept—Are Nature and Nurture Definable in Fishery Science?
Authors: Booke Henry E.
Published: May 2008

The definition of the word stock, as applied in fishery science, is presented in general and in precise forms. The general definition is a species group, or population, of fish that maintains and sustains itself over time in a definable area. In a more precise manner, stock (genotypic) is defined as a population of fish maintaining and sustaining Castle–Hardy–Weinberg equilibrium. If a genetic basis is not available for stock characterization, then a phenotypic stock definition has to be recognized as a population of fish maintaining characteristics which are expressed in one or more ways, depending on the type or nature of environment of domicile.Key words: fish stocks, definition
Use of Allelic Frequencies to Describe Population Structure
Authors: Allendorf Fred W. , Phelps Stevan R.
Published: May 2008

Development of electrophoretic techniques has allowed the estimation of allelic frequencies at many isozyme loci in populations of fish. The pattern of allelic frequency divergence in salmonid populations has been used to describe the pattern of genetic exchange and degree of isolation among local geographic units. Our goal is to determine how much genetic exchange among subpopulations will yield observed patterns of allelic divergence. We approach this goal using population genetics theory and a series of computer simulations.The amount of allelic divergence between subpopulations is a function of the absolute number of migrant individuals exchanged, and not the proportion of individuals exchanged. Therefore, some knowledge of population sizes is needed to estimate degree of reproductive isolation from allelic frequency data. Second, statistically significant allelic divergence will often be present even when there is substantial exchange among subpopulations. For example, significant allelic divergence was present in our simulations over 50% of the time with 20 subpopulations exchanging 50 individuals per generation. Third, allelic frequencies estimated from fry should be used with caution when drawing conclusions about the significance of allelic divergence in the reproducing adults.Key words: allelic divergence, reproductive isolation, gene flow, genetic drift, computer simulations