bluuebunny/crossref_metadata_2025_split huggingface dataset:
SENSITIVITY ANALYSIS OF THE STOCHASTIC GROWTH RATE: THREE EXTENSIONS†
Authors: Caswell Hal 
Published: February 2005

SummaryThe perturbation analysis of population growth rate plays an important role in population biology. The sensitivity and/or elasticity (proportional sensitivity) of population growth rate to changes in the vital rates are regularly used (i) to predict the effects of environmental perturbations, (ii) to characterize selection gradients on life‐history traits, (iii) to evaluate management tactics, (iv) to analyse life table response experiments, and (v) to calculate the sampling variance in population growth rate. In a stochastic environment, population growth is described by the stochastic growth rate, which gives, with probability 1, the asymptotic time‐averaged growth rate of any realization. Tuljapurkar derived the sensitivity and elasticity of the stochastic growth rate to changes in the entries of the stochastic matrices. This paper extends his result to cover three cases, each of which has arisen recently in applications. The first gives the response of the stochastic growth rate to environment‐specific perturbations, applied only in a specified subset of the possible environments. The second gives the sensitivity and elasticity of the stochastic growth rate to changes in lower‐level parameters. The third applies to stochastic seasonal models, in which the projection matrix for each year is a periodic product of matrices describing seasonal transitions. In this case interest focuses on the sensitivity of the stochastic growth rate to changes in the entries of the seasonal matrices, not entries in the annual matrices. The paper describes examples of problems where each of these extensions is needed, and the algorithms for each of the new calculations.
Correlation between volume fraction and volume‐weighted mean volume, and between total number and total mass of islets in post‐weaning and young Wistar rats
Authors: Inuwa I. M. , El Mardi A. S. 
Published: February 2005

AbstractThe aim of this study was to estimate the number and volume distribution of islets of Langerhans in post‐weaning young Wistar rat pancreas and their variation with age. Four groups of six normal Wistar Kyoto rats, at 3, 6, 9 and 12 weeks of age, were used. The whole pancreas was weighed (W), fixed in buffered formaldehyde and embedded in JB4 resin, and 1.5‐µm serial sections were obtained. A fraction of whole tissue was obtained in accordance with the multistage fractionator principle and used to estimate total number of islets (Nis). Volume fraction (Vf) of islets and volume‐weighted mean volume (Vv) of islets were estimated using point‐counting and point‐sampled intercept methods, respectively. The numbers of islets increased steadily with age (P < 0.001), whereas the volume‐weighted mean volume of individual islets was not significantly different among all age groups of rats (P > 0.05). There was a strong positive correlation between total islet number and islet mass (r = 0.96, P = 0.001), and between volume fraction and islet mass (r = 0.969, P = 0.001). However, there was a weak positive correlation between volume fraction and volume‐weighted mean islet volume (r = 0.6, P = 0.002) in the age window investigated. These findings indicate that there was an increase in the number and volume fraction of islets with age in post‐weaning young rats but that individual islet volume did not change significantly. It appears the mechanism of alteration in islet morphology in the rat is mainly by the formation of new islets while keeping their individual volume distribution unchanged.
β‐Catenin expression during vascular development and degeneration of avian mesonephros
Authors: Nacher Víctor , Carretero Ana , Navarro Marc , Armengol Clara , Llombart Cristina , Blasi Juan , Ruberte Jesús 
Published: February 2005

Abstractβ‐Catenin is a structural component of adherens junctions, a regulator of the Wnt signalling pathway and a transcriptional co‐activator with a key role in vascular patterning. The avian mesonephros is a transitory embryonic kidney that is used in the study of vascular development and degeneration. Here we examine β‐catenin expression in this model during vascular development and degeneration. Quail embryos with developing or degenerating mesonephros were studied, on day 6 (30HH) or day 11 of incubation (40HH), respectively. QH1 whole mounts of developing mesonephros revealed numerous angioblast‐like cells situated in the paramesonephric duct that seem to invade the mesonephros. Although these cells did not express β‐catenin, the surrounding periductal mesenchymal cells translocated high levels of β‐catenin into the nucleus. In contrast, degenerating mesonephros were devoid of angioblast‐like cells and β‐catenin was lower than in the developing mesonephros. β‐Catenin was significantly reduced in the glomerular capillary tuffs, indicating that it was particularly down‐regulated in the vascular system. No sex‐related differences in β‐catenin expression were observed in degenerating mesonephros. Furthermore, two special populations of glomerular and peritubular endothelial cells were observed in degenerating mesonephros: one translocating β‐catenin into the nucleus and the other in apoptosis that did not translocate it. In conclusion, our results indicate that the paramesonephric duct is a potential new vasculogenetic pathway, and suggest that β‐catenin plays a role in the fate of mesonephric endothelial cells.
Obstetric outcomes among rural Aboriginal Victorians
Authors: SIMMONS David , KHAN Munir A. , TEALE Glyn 
Published: February 2005

AbstractTwenty‐eight Aboriginal women and 112 age‐matched controls were identified from a retrospective chart review of deliveries over a 1‐year period in northern Victoria. Significantly more Aboriginal women were screened for gestational diabetes and met criteria for the diagnosis of gestational diabetes. Overall mode of delivery was similar amongst the two groups. Babies born to Aboriginal mothers were significantly smaller and less likely to be breast fed than those from the non‐Aboriginal group.
Dental Caries, Periodontal Disease, and Cardiac Arrhythmias in Community‐Dwelling Older Persons Aged 80 and Older: Is There a Link?
Authors: Holm‐Pedersen Poul , Avlund Kirsten , Morse Douglas E. , Stoltze Kaj , Katz Ralph V. , Viitanen Matti , Winblad Bengt 
Published: February 2005

Objectives: To examine whether caries or periodontitis is associated with cardiac arrhythmias in community‐dwelling people aged 80 and older.Setting: Urban, community‐based population in Stockholm, Sweden.Design: Cross‐sectional.Participants: Eligible persons were identified through the Kungsholmen Project, which is an ongoing, longitudinal, population‐based study of the oldest old. The present study included 125 dentate individuals.Measurements: Data from interviews, a medical examination, and an oral examination. The assessment of cardiac arrhythmia was based on a clinical examination by a physician or the Stockholm Inpatient Register. Active root caries, active coronal caries, and periodontitis were assessed using previously defined National Institute of Dental and Craniofacial Research diagnostic criteria.Results: The primary finding of the multivariate logistic regression analysis was that persons with three or more active root caries lesions had more than twice the odds of cardiac arrhythmias than persons without active root caries. The results did not notably change after adjusting for age, medications that reduce saliva, and number of teeth. Persons with one to two active coronal caries lesions had 2.8 times higher odds (95% confidence interval=1.1–7.0) of arrhythmia than persons without active coronal caries, but there was no greater risk for persons with three or more coronal caries lesions. There was no association between periodontal disease and arrhythmia.Conclusion: The findings indicate that there may be a link between active root caries and cardiac arrhythmias in the oldest old. Nevertheless, although a biological pathway is not obvious, it is plausible that both are simply markers of declining general health. The results suggest the need for further study of these relationships.
Pneumonia in Nursing Home Residents: Factors Associated with In‐Home Care of EverCare Enrollees
Authors: Rector Thomas S. , Spector William D. , Shaffer Thomas J. , Finch Michael D. 
Published: February 2005

Objectives: To identify determinants of whether nursing home (NH) residents enrolled in EverCare were admitted to in‐home intensive service days (ISDs) rather than a hospital when they were thought to have pneumonia.Design: Retrospective cross‐sectional.Setting: EverCare operations in five metropolitan areas.participants: EverCare enrollees admitted to ISDs or a hospital for suspected pneumonia in 2002.Measurements: Member, nurse practitioner, physician, and NH characteristics extracted from EverCare's administrative data and Online Survey Certification and Reporting NH data.Results: Multivariable logistic regression indicated that admission to ISDs (65% of cases) was positively associated with age (odds ratio (OR)=1.04. 95% confidence interval (CI) 1.03–1.04), advance directives not to hospitalize (OR=2.88, 95% CI=1.76–4.72), or perform cardiopulmonary resuscitation, 3.09 (2.44–3.91), and hours worked by the NH's registered nurses (OR=4.34, 95% CI=1.74–10.8). Admission to ISD was less likely on weekends (OR=0.30, 95% CI=0.21–0.43), when residents had renal insufficiency (OR=0.61, 95% CI=0.49–0.76), and when the resident was covered by Medicaid (OR 0.87, 95% CI=0.82–0.93).Conclusion: Exploration of ways to extend services to weekends, increased availability of registered nurse staff, attention to advance directives, and a better understanding of the role of Medicaid might increase the likelihood of caring for EverCare enrollees with suspected pneumonia in their NH.
Sampling Issues in the Administration of Justice
Authors: Aitken Colin 
Published: February 2005

Abstract
Colin Aitken first became interested in sampling in the context of the administration of justice when the case of US versus Shonubi was brought to his attention. Shonubi was a Nigerian working in New York. He was arrested at Kennedy Airport when seen behaving in a suspicious manner in the baggage hall, having returned on a flight from Nigeria. He was found to have 103 bags of a white substance inside him, four of which were examined. The white substance was identified as heroin. Shonubi was arrested, tried and found guilty of drug smuggling. The question then arose as to the length of sentence he should be given.
EFFECTS OF COLLAGEN ADDITION ON THE FUNCTIONALITY OF PSE‐LIKE AND NORMAL BROILER BREAST MEAT IN A CHUNKED AND FORMED DELI ROLL
Authors: SCHILLING M.W. , DAIGLE S.P. , ALVARADO C.Z. , MARRIOTT N.G. , WANG H. 
Published: February 2005

ABSTRACT A Randomized Complete Block Design with six replications was utilized to test the treatment effects of raw material and the inclusion of chicken collagen on the protein functionality of chunked and formed chicken breast manufactured from 100% pale, soft, and exudative like (PSE‐like) and 100% normal broiler breast with either 0 or 1.5% collagen. Inclusion of collagen was effective in decreasing cooking loss and increasing protein–protein bind. Differences (P < 0.05) revealed that collagen inclusion caused PSE‐like meat to have lower cooking loss. Collagen addition also increased (P < 0.05) bind so that the PSE‐like treatment was not different from the normal treatment with collagen added. However, PSE‐like with no collagen had lower (P < 0.05) protein–protein bind (kg) than normal meat with collagen. These results reveal that addition of chicken collagen has the potential to improve quality characteristics of chunked and formed deli rolls formulated from both PSE‐like and normal raw material.
Susceptibility of Germfree Phagocyte Oxidase- and Nitric Oxide Synthase 2-Deficient Mice, Defective in the Production of Reactive Metabolites of Both Oxygen and Nitrogen, to Mucosal and Systemic Candidiasis of Endogenous Origin
Authors: Balish Edward , Warner Thomas F. , Nicholas Peter J. , Paulling Emily E. , Westwater Caroline , Schofield David A. 
Published: February 2005

ABSTRACT

Mice deficient for phagocyte oxidase (Phox) and nitric oxide synthase 2 (NOS2) (gp91
phox−/−
/NOS2
−/−
), defective in the production of both reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI), were used to investigate the role of phagocytic cells during mucosal and systemic candidiasis of endogenous origin. The alimentary tracts of germfree mice were colonized with
Candida albicans
wild type or each of two hyphal signaling-defective mutants (
efg1/efg1
and
efg1/efg1 cph1/cph1
). All
Candida
-colonized gp91
phox−/−
/NOS2
−/−
mice were moribund within 12 to 15 days after oral inoculation.
C. albicans
wild-type and mutant strains colonized the alimentary tracts equally well and were able to translocate, most likely via Peyer's patches and mesenteric lymph nodes, to the internal organs and trigger the formation of abscesses; however, the wild-type and mutant strains did not survive in the abscessed murine tissues. Surprisingly, there was no significant difference in the ability of peritoneal exudate cells from gp91
phox−/−
/NOS2
−/−
, NOS2
−/−
, gp91
phox−/−
, or immunocompetent C57BL/6 mice to kill
C. albicans
in vitro. This suggests that anti
-Candida
factors other than ROI and RNI can control the growth of
C. albicans
and that gp91
phox−/−
/NOS2
−/−
mice die due to the inability of the host to control its inflammatory response to
Candida
. Correspondingly, reverse transcription-PCR analysis showed increased expression of the cytokines gamma interferon, tumor necrosis factor alpha, and the chemokines MIP-2 and KC at the site of infection, while interleukin-15 expression remained relatively unchanged between germfree and infected tissues. These studies indicate that defects in ROI and RNI enabled
C. albicans
to translocate and disseminate to the internal organs, resulting in an uncontrolled immune response, severe pathology, and death; however, ROI and RNI were not required for the killing of phagocytized
C. albicans
, indicating that other anti-
Candida
factors either compensate or are sufficient for the killing of phagocytized
Candida
.
Toll-Like Receptor 2 Mediates Cellular Activation by the B Subunits of Type II Heat-Labile Enterotoxins
Authors: Hajishengallis George , Tapping Richard I. , Martin Michael H. , Nawar Hesham , Lyle Elizabeth A. , Russell Michael W. , Connell Terry D. 
Published: February 2005

ABSTRACTThe type II heat-labile enterotoxins (LT-IIa and LT-IIb) ofEscherichia colihave an AB5subunit structure similar to that of cholera toxin (CT) and other type I enterotoxins, despite significant differences in the amino acid sequences of their B subunits and different ganglioside receptor specificities. LT-II holotoxins and their nontoxic B subunits display unique properties as immunological adjuvants distinct from those of CT and its B subunits. In contrast to type II holotoxins, the corresponding pentameric B subunits, LT-IIaB and LT-IIbB, stimulated cytokine release in both human and mouse cells dependent upon Toll-like receptor 2 (TLR2). Induction of interleukin-1β (IL-1β), IL-6, IL-8, or tumor necrosis factor alpha in human THP-1 cells by LT-IIaB or LT-IIbB was inhibited by anti-TLR2 but not by anti-TLR4 antibody. Furthermore, transient expression of TLR1 and TLR2 in human embryonic kidney 293 cells resulted in activation of a nuclear factor-κB-dependent luciferase gene in response to LT-IIaB or LT-IIbB. Moreover, peritoneal macrophages from TLR2-deficient mice failed to respond to LT-IIaB or LT-IIbB, in contrast to wild-type or TLR4-deficient cells. These results demonstrate that besides their established binding to gangliosides, the B subunits of type II enterotoxins also interact with TLR2. Although a ganglioside-nonbinding mutant (T34I) of LT-IIaB effectively induced cytokine release, a phenotypically similar point mutation (T13I) in LT-IIbB abrogated cytokine induction, suggesting a variable requirement for gangliosides as coreceptors in TLR2 agonist activity. TLR2-dependent activation of mononuclear cells by type II enterotoxin B subunits appears to be a novel mechanism whereby these molecules may exert their immunomodulatory and adjuvant activities.
Citrobacter rodentium lifA
/
efa1
Is Essential for Colonic Colonization and Crypt Cell Hyperplasia In Vivo
Authors: Klapproth Jan-Michael A. , Sasaki Maiko , Sherman Melanie , Babbin Brian , Donnenberg Michael S. , Fernandes Paula J. , Scaletsky Isabel C. A. , Kalman Daniel , Nusrat Asma , Williams Ifor R. 
Published: February 2005

ABSTRACT

Previously, we have identified a large gene (
lifA
, for lymphocyte inhibitory factor A) in enteropathogenic
Escherichia coli
(EPEC) encoding a protein termed lymphostatin that suppresses cytokine expression in vitro. This protein also functions as an adhesion factor for enterohemorrhagic
E. coli
(EHEC) and Shiga toxin-producing
E. coli
and is alternatively known as
efa1
(EHEC factor for adherence 1). The
lifA
/
efa1
gene is also present in
Citrobacter rodentium
, an enteric pathogen that causes a disease termed transmissible murine colonic hyperplasia (TMCH), which induces colitis and massive crypt cell proliferation, in mice. To determine if
lifA
/
efa1
is required for
C. rodentium
-induced colonic pathology in vivo, three in-frame mutations were generated, disrupting the glycosyltransferase (GlM12) and protease (PrMC31) motifs and a domain in between that does not encode any known activity (EID3). In contrast to infection with wild-type
C. rodentium
, that with any of the
lifA
/
efa1
mutant strains did not induce weight loss or TMCH. Enteric infection with motif mutants GlM12 and PrM31 resulted in significantly reduced colonization counts during the entire 20-day course of infection. In contrast, EID3 was indistinguishable from the wild type during the initial colonic colonization, but cleared rapidly after day 8 of the infection. The colonic epithelium of all infected mice displayed increased epithelial regeneration. However, significantly increased regeneration was observed by day 20 only in mice infected with the wild-type in comparison to those infected with
lifA
/
efa1
mutant EID3. In summary,
lifA
/
efa1
is a critical gene outside the locus for enterocyte effacement that regulates bacterial colonization, crypt cell proliferation, and epithelial cell regeneration.
Natural Killer Cells andHelicobacter pyloriInfection: Bacterial Antigens and Interleukin-12 Act Synergistically To Induce Gamma Interferon Production
Authors: Yun Cheol H. , Lundgren Anna , Azem Josef , Sjöling Åsa , Holmgren Jan , Svennerholm Ann-Mari , Lundin B. Samuel 
Published: February 2005

ABSTRACTHelicobacter pyloriis known to induce a local immune response, which is characterized by activation of lymphocytes and the production of IFN-γ in the stomach mucosa. Since not only T cells, but also natural killer (NK) cells, are potent producers of gamma interferon (IFN-γ), we investigated whether NK cells play a role in the immune response toH. pyloriinfection. Our results showed that NK cells were present in both the gastric and duodenal mucosae but thatH. pyloriinfection did not affect the infiltration of NK cells into the gastrointestinal area. Furthermore, we could show that NK cells could be activated directly byH. pyloriantigens, asH. pyloribacteria, as well as lysate fromH. pylori, induced the secretion of IFN-γ by NK cells. NK cells were also activated without direct contact when separated from the bacteria by an epithelial cell layer, indicating that the activation of NK cells byH. pylorican also occur in vivo, in the infected stomach mucosa. Moreover, the production of IFN-γ by NK cells was greatly enhanced when a small amount of interleukin-12 (IL-12) was added, and this synergistic effect was associated with increased expression of the IL-12 receptor β2. It was further evident that bacterial lysate alone was sufficient to induce the activation of cytotoxicity-related molecules. In conclusion, we demonstrated that NK cells are present in the gastroduodenal mucosa of humans and that NK cells produce high levels of IFN-γ when stimulated with a combination ofH. pyloriantigen and IL-12. We propose that NK cells play an active role in the local immune response toH. pyloriinfection.
Innate Immunity to the Pathogenic Fungus
Coccidioides posadasii
Is Dependent on Toll-Like Receptor 2 and Dectin-1
Authors: Viriyakosol Suganya , Fierer Joshua , Brown Gordon D. , Kirkland Theo N. 
Published: February 2005

ABSTRACT

Coccidioides posadasii
is a pathogenic fungus that causes endemic and epidemic coccidioidomycosis in the deserts of North, Central, and South America. How the innate immune system responds to the organism is not well understood. Here we show that elicited mouse peritoneal macrophages respond to spherules (the tissue form of the fungus) by producing proinflammatory cytokines as measured by quantitative PCR of cellular transcripts and by enzyme-linked immunosorbent assay (ELISA) assays for secreted protein. We examined the contribution of Toll-like receptors (TLR) and MyD88 in macrophage responses to formalin-killed spherules (FKS) by comparing cytokine responses of elicited macrophages from different knockout mice. FKS were added to elicited mouse peritoneal macrophages from wild-type, TLR2
−/−
, and MyD88
−/−
cells, and wild-type cells made more tumor necrosis factor alpha, MIP-2, and interleukin 6 than did the mutant macrophages. In contrast, the C3H/HeJ mice, which have a point mutation in TLR4, and TLR4
−/−
B6 mice exhibited no defect in cytokine production compared to the control mice. We also investigated the role of the macrophage β-glucan receptor, Dectin-1. RAW 264.7 macrophages overexpressing Dectin-1 produced more cytokines in respond to FKS, live spherules, and purified β-glucan than did control RAW cells. Blockage of Dectin-1 with antibodies inhibited cytokine production in elicited mouse peritoneal macrophages. Taken together, these results show that cytokine responses in mouse peritoneal macrophages to
C. posadasii
spherules are dependent on TLR2, MyD88, and Dectin-1.