bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating Early Events in Receptor Binding and Translocation of Colicin E9 Using Synchronized Cell Killing and Proteolytic Cleavage
Authors: Zhang Ying , Vankemmelbeke Mireille N. , Holland Lisa E. , Walker David C. , James Richard , Penfold Christopher N.
Published: April 2008

Enzymatic colicins such as colicin E9 (ColE9) bind to BtuB on the cell surface of
Escherichia coli
and rapidly recruit a second coreceptor, either OmpF or OmpC, through which the N-terminal natively disordered region (NDR) of their translocation domain gains entry into the cell periplasm and interacts with TolB. Previously, we constructed an inactive disulfide-locked mutant ColE9 (ColE9
s-s
) that binds to BtuB and can be reduced with dithiothreitol (DTT) to synchronize cell killing. By introducing unique enterokinase (EK) cleavage sites in ColE9
s-s
, we showed that the first 61 residues of the NDR were inaccessible to cleavage when bound to BtuB, whereas an EK cleavage site inserted at residue 82 of the NDR remained accessible. This suggests that most of the NDR is occluded by OmpF shortly after binding to BtuB, whereas the extreme distal region of the NDR is surface exposed before unfolding of the receptor-binding domain occurs. EK cleavage of unique cleavage sites located in the ordered region of the translocation domain or in the distal region of the receptor-binding domain confirmed that these regions of ColE9 remained accessible at the
E. coli
cell surface. Lack of EK cleavage of the DNase domain of the cell-bound, oxidized ColE9/Im9 complex, and the rapid detection of Alexa Fluor 594-labeled Im9 (Im9
AF
) in the cell supernatant following treatment of cells with DTT, suggested that immunity release occurred immediately after unfolding of the colicin and was not driven by binding to BtuB.
Transcriptional Regulation of the Nitrile Hydratase Gene Cluster in
Pseudomonas chlororaphis
B23
Authors: Sakashita Toshihide , Hashimoto Yoshiteru , Oinuma Ken-Ichi , Kobayashi Michihiko
Published: April 2008

An enormous amount of nitrile hydratase (NHase) is inducibly produced by
Pseudomonas chlororaphis
B23 after addition of methacrylamide as the sole nitrogen source to a medium. The expression pattern of the
P. chlororaphis
B23 NHase gene cluster in response to addition of methacrylamide to the medium was investigated. Recently, we reported that the NHase gene cluster comprises seven genes (
oxdA
,
amiA
,
nhpA
,
nhpB
,
nhpC
,
nhpS
, and
acsA
). Sequence analysis of the 1.5-kb region upstream of the
oxdA
gene revealed the presence of a 936-bp open reading frame (designated
nhpR
), which should encode a protein with a molecular mass of 35,098. The deduced amino acid sequence of the
nhpR
product showed similarity to the sequences of transcriptional regulators belonging to the XylS/AraC family. Although the transcription of the eight genes (
nhpR
,
oxdA
,
amiA
,
nhpABC
,
nhpS
, and
acsA
) in the NHase gene cluster was induced significantly in the
P. chlororaphis
B23 wild-type strain after addition of methacrylamide to the medium, transcription of these genes in the
nhpR
disruptant was not induced, demonstrating that
nhpR
codes for a positive transcriptional regulator in the NHase gene cluster. A reverse transcription-PCR experiment revealed that five genes (
oxdA
,
amiA
,
nhpA
,
nhpB
, and
nhpC
) are cotranscribed, as are two other genes (
nhpS
and
acsA
). The transcription start sites for
nhpR
,
oxdA
,
nhpA
, and
nhpS
were mapped by primer extension analysis, and putative −12 and −24 σ
54
-type promoter binding sites were identified. NhpR was found to be the first transcriptional regulator of NHase belonging to the XylS/AraC family.
Genetic and Biochemical Characterization of the Poly(3-Hydroxybutyrate-
co
-3-Hydroxyvalerate) Synthase in
Haloferax mediterranei
Authors: Lu Qiuhe , Han Jing , Zhou Ligang , Zhou Jian , Xiang Hua
Published: April 2008

The haloarchaeon
Haloferax mediterranei
has shown promise for the economical production of poly(3-hydroxybutyrate-
co
-3-hydroxyvalerate) (PHBV), a desirable bioplastic. However, little is known at present about the genes involved in PHBV synthesis in the domain
Archaea
. In this study, we cloned the gene cluster (
phaEC
Hme
) encoding a polyhydroxyalkanoate (PHA) synthase in
H. mediterranei
CGMCC 1.2087 via thermal asymmetric interlaced PCR. Western blotting revealed that the
phaE
Hme
and
phaC
Hme
genes were constitutively expressed, and both the PhaE
Hme
and PhaC
Hme
proteins were strongly bound to the PHBV granules. Interestingly, CGMCC 1.2087 could synthesize PHBV in either nutrient-limited medium (supplemented with 1% starch) or nutrient-rich medium, up to 24 or 18% (wt/wt) in shaking flasks. Knockout of the
phaEC
Hme
genes in CGMCC 1.2087 led to a complete loss of PHBV synthesis, and only complementation with the
phaEC
Hme
genes together (but not either one alone) could restore to this mutant the capability for PHBV accumulation. The known haloarchaeal PhaC subunits are much longer at their C termini than their bacterial counterparts, and the C-terminal extension of PhaC
Hme
was proven to be indispensable for its function in vivo. Moreover, the mixture of purified PhaE
Hme
/PhaC
Hme
(1:1) showed significant activity of PHA synthase in vitro. Taken together, our results indicated that a novel member of the class III PHA synthases, composed of PhaC
Hme
and PhaE
Hme
, accounted for the PHBV synthesis in
H. mediterranei
.
The
Aeromonas hydrophila wb
*
O34
Gene Cluster: Genetics and Temperature Regulation
Authors: Jimenez Natalia , Canals Rocío , Saló María Teresa , Vilches Silvia , Merino Susana , Tomás Juan M.
Published: April 2008

The
Aeromonas hydrophila wb
*
O34
gene cluster of strain AH-3 (serotype O34) was cloned and sequenced. This cluster contains genes necessary for the production of O34-antigen lipopolysaccharide (LPS) in
A. hydrophila
. We determined, using either mutation or sequence homology, roles for the majority of genes in the cluster by using the chemical O34-antigen LPS structure obtained for strain AH-3. The O34-antigen LPS export system has been shown to be a Wzy-dependent pathway typical of heteropolysaccharide pathways. Furthermore, the production of
A. hydrophila
O34-antigen LPS in
Escherichia coli
K-12 strains is dependent on incorporation of the Gne enzyme (UDP-
N
-acetylgalactosamine 4-epimerase) necessary for the formation of UDP-galactosamine in these strains. By using rapid amplification of cDNA ends we were able to identify a transcription start site upstream of the terminal
wzz
gene, which showed differential transcription depending on the growth temperature of the strain. The Wzz protein is able to regulate the O34-antigen LPS chain length. The differential expression of this protein at different temperatures, which was substantially greater at 20°C than at 37°C, explains the previously observed differential production of O34-antigen LPS and its correlation with the virulence of
A. hydrophila
serotype O34 strains.
Unusual, Virulence Plasmid-Dependent Growth Behavior of
Yersinia enterocolitica
in Three-Dimensional Collagen Gels
Authors: Freund Sandra , Czech Beate , Trülzsch Konrad , Ackermann Nikolaus , Heesemann Jürgen
Published: April 2008

As a first approach to establishing a three-dimensional culture infection model, we studied the growth behavior of the extracellular pathogen
Yersinia enterocolitica
in three-dimensional collagen gels (3D-CoG). Surprisingly, we observed that plasmidless
Y. enterocolitica
was motile in the 3D-CoG in contrast to its growth in traditional motility agar at 37°C. Motility at 37°C was abrogated in the presence of the virulence plasmid pYV or the exclusive expression of the pYV-located
Yersinia
adhesion gene
yadA
. YadA-producing yersiniae formed densely packed (dp) microcolonies, whereas pYVΔ
yadA
-carrying yersiniae formed loosely packed microcolonies at 37°C in 3D-CoG. Furthermore, we demonstrated that the packing density of the microcolonies was dependent on the head domain of YadA. Moreover, dp microcolony formation did not depend on the capacity of YadA to bind to collagen fibers, as demonstrated by the use of yersiniae producing collagen nonbinding YadA. By using a
yopE-gfp
reporter, we demonstrated Ca
2+
-dependent expression of this pYV-localized virulence gene by yersiniae in 3D-CoG. In conclusion, this study revealed unique plasmid-dependent growth behavior of yersiniae in a three-dimensional matrix environment that resembles the behavior of yersiniae (e.g., formation of microcolonies) in infected mouse tissue. Thus, this 3D-CoG model may be a first step to a more complex level of in vitro infection models that mimic living tissue, enabling us to study the dynamics of pathogen-host cell interactions.
Characterization of
abn2
(
yxiA
), Encoding a
Bacillus subtilis
GH43 Arabinanase, Abn2, and Its Role in Arabino-Polysaccharide Degradation
Authors: Inácio José Manuel , de Sá-Nogueira Isabel
Published: April 2008

The extracellular depolymerization of arabinopolysaccharides by microorganisms is accomplished by arabinanases, xylanases, and galactanases. Here, we characterize a novel endo-α-1,5-
l
-arabinanase (EC 3.2.1.99) from
Bacillus subtilis
, encoded by the
yxiA
gene (herein renamed
abn2
) that contributes to arabinan degradation. Functional studies by mutational analysis showed that Abn2, together with previously characterized AbnA, is responsible for the majority of the extracellular arabinan activity in
B. subtilis
. Abn2 was overproduced in
Escherichia coli
, purified from the periplasmic fraction, and characterized with respect to substrate specificity and biochemical and physical properties. With linear-α-1,5-
l
-arabinan as the preferred substrate, the enzyme exhibited an apparent

K
m

of 2.0 mg ml
−1
and
V
max
of 0.25 mmol min
−1
mg
−1
at pH 7.0 and 50°C. RNA studies revealed the monocistronic nature of
abn2
. Two potential transcriptional start sites were identified by primer extension analysis, and both a σ
A
-dependent and a σ
H
-dependent promoter were located. Transcriptional fusion studies revealed that the expression of
abn2
is stimulated by arabinan and pectin and repressed by glucose; however, arabinose is not the natural inducer. Additionally,
trans
-acting factors and
cis
elements involved in transcription were investigated. Abn2 displayed a control mechanism at a level of gene expression different from that observed with AbnA. These distinct regulatory mechanisms exhibited by two members of extracellular glycoside hydrolase family 43 (GH43) suggest an adaptative strategy of
B. subtilis
for optimal degradation of arabinopolysaccharides.
The Peptidoglycan of Stationary-Phase
Mycobacterium tuberculosis
Predominantly Contains Cross-Links Generated by
l,d
-Transpeptidation
Authors: Lavollay Marie , Arthur Michel , Fourgeaud Martine , Dubost Lionel , Marie Arul , Veziris Nicolas , Blanot Didier , Gutmann Laurent , Mainardi Jean-Luc
Published: April 2008

Our understanding of the mechanisms used by
Mycobacterium tuberculosis
to persist in a “dormant” state is essential to the development of therapies effective in sterilizing tissues. Gene expression profiling in model systems has revealed a complex adaptive response thought to endow
M. tuberculosis
with the capacity to survive several months of combinatorial antibiotic treatment. We show here that this adaptive response may involve remodeling of the peptidoglycan network by substitution of 4→3 cross-links generated by the
d
,
d
-transpeptidase activity of penicillin-binding proteins by 3→3 cross-links generated by a transpeptidase of
l,d
specificity. A candidate gene, previously shown to be upregulated upon nutrient starvation, was found to encode an
l,d
-transpeptidase active in the formation of 3→3 cross-links. The enzyme, Ldt
Mt1
, was inactivated by carbapenems, a class of β-lactam antibiotics that are poorly hydrolyzed by the
M. tuberculosis
β-lactamases. Ldt
Mt1
and carbapenems may therefore represent a target and a drug family relevant to the eradication of persistent
M. tuberculosis
.
Complete Genome Sequence of the Soil Actinomycete
Kocuria rhizophila
Authors: Takarada Hiromi , Sekine Mitsuo , Kosugi Hiroki , Matsuo Yasunori , Fujisawa Takatomo , Omata Seiha , Kishi Emi , Shimizu Ai , Tsukatani Naofumi , Tanikawa Satoshi , Fujita Nobuyuki , Harayama Shigeaki
Published: April 2008

The soil actinomycete
Kocuria rhizophila
belongs to the suborder
Micrococcineae
, a divergent bacterial group for which only a limited amount of genomic information is currently available.
K. rhizophila
is also important in industrial applications; e.g., it is commonly used as a standard quality control strain for antimicrobial susceptibility testing. Sequencing and annotation of the genome of
K. rhizophila
DC2201 (NBRC 103217) revealed a single circular chromosome (2,697,540 bp; G+C content of 71.16%) containing 2,357 predicted protein-coding genes. Most of the predicted proteins (87.7%) were orthologous to actinobacterial proteins, and the genome showed fairly good conservation of synteny with taxonomically related actinobacterial genomes. On the other hand, the genome seems to encode much smaller numbers of proteins necessary for secondary metabolism (one each of nonribosomal peptide synthetase and type III polyketide synthase), transcriptional regulation, and lateral gene transfer, reflecting the small genome size. The presence of probable metabolic pathways for the transformation of phenolic compounds generated from the decomposition of plant materials, and the presence of a large number of genes associated with membrane transport, particularly amino acid transporters and drug efflux pumps, may contribute to the organism's utilization of root exudates, as well as the tolerance to various organic compounds.
Negative Regulation of Quorum-Sensing Systems inPseudomonas aeruginosaby ATP-Dependent Lon Protease
Authors: Takaya Akiko , Tabuchi Fumiaki , Tsuchiya Hiroko , Isogai Emiko , Yamamoto Tomoko
Published: April 2008

Lon protease, a member of the ATP-dependent protease family, regulates numerous cellular systems by degrading specific substrates. Here, we demonstrate that Lon is involved in the regulation of quorum-sensing (QS) signaling systems inPseudomonas aeruginosa, an opportunistic human pathogen. The organism has two acyl-homoserine lactone (HSL)-mediated QS systems, LasR/LasI and RhlR/RhlI. Many reports have demonstrated that these two systems are regulated and interconnected by global regulators. We found thatlon-disrupted cells overproduce pyocyanin, the biosynthesis of which depends on the RhlR/RhlI system, and show increased levels of a transcriptional regulator, RhlR. The QS systems are organized hierarchically: the RhlR/RhlI system is subordinate to LasR/LasI. To elucidate the mechanism by which Lon negatively regulates RhlR/RhlI, we examined the effect oflondisruption on the LasR/LasI system. We found that Lon represses the expression of LasR/LasI by degrading LasI, an HSL synthase, leading to negative regulation of the RhlR/RhlI system. RhlR/RhlI was also shown to be regulated by Lon independently of LasR/LasI via regulation of RhlI, an HSL synthase. In view of these findings, it is suggested that Lon protease is a powerful negative regulator of both HSL-mediated QS systems inP. aeruginosa.
Role of Differential Expression of Streptococcal Arginine Deiminase in Inhibition of
fimA
Expression in
Porphyromonas gingivalis
Authors: Lin Xinghua , Lamont Richard J. , Wu Jie , Xie Hua
Published: April 2008

Streptococcus cristatus
ArcA inhibits production of a major adhesin, FimA, in
Porphyromonas gingivalis
, a primary periodontal pathogen. In this study, we demonstrate the differential expression of
arcA
in two streptococcal species. The expression level of
arcA
in streptococci appears to be controlled by both
cis
and
trans
elements.
Angiotensin II receptor antagonism reverts the selective cardiac BNP upregulation and secretion observed in myocarditis
Authors: Ogawa Tsuneo , Veinot John P. , Kuroski de Bold Mercedes L. , Georgalis Tina , de Bold Adolfo J.
Published: April 2008

The cardiac natriuretic peptides atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) are discoordinately regulated in myocardial inflammation associated with acute allograft rejection in humans and during in vitro exposure of cardiocyte cultures to some proinflammatory cytokines. We used experimental autoimmune myocarditis (EAM) to determine whether the discoordinate regulation of ANF and BNP was specific to the situations above or was generally associated with other types of myocardial inflammation. The dependency of this process to angiotensin signaling was also determined, given that previous work demonstrated beneficial effects of the angiotensin receptor blocker olmesartan in myocarditis. Histopathological changes, plasma and cardiac ANF, BNP, and selected cytokines gene expression as well as plasma cytokine levels using a cytokine array were determined in EAM, angiotensin receptor blocker-treated, and control rats. It was found that EAM specifically increases BNP but not ANF circulating levels, thus mimicking the findings in acute cardiac allograft rejection and the effect of some proinflammatory cytokines on cardiocyte cultures in vitro. Plasma cytokine array and real-time PCR revealed that lipopolysaccharide-induced CXC chemokine, monocyte chemotactic protein-1, and tissue inhibitor of metalloproteinase-1 were increased in plasma and in the myocardium of EAM rats. Olmesartan treatment reversed virtually all neuroendocrine and histopathological cardiac changes induced by EAM, thus providing a mechanistic insight into this phenomenon. It is concluded that the inflammatory process contributes specific cytokines, leading to the disregulation of cardiac ANF and BNP production observed during myocardial inflammation, and that this process is angiotensin receptor 1 dependent.
VEGF promotes vascular sympathetic innervation
Authors: Marko Stephen B. , Damon Deborah H.
Published: April 2008

The sympathetic nervous system, via postganglionic innervation of blood vessels and the heart, is an important determinant of cardiovascular function. The mechanisms underlying sympathetic innervation of targets are not fully understood. This study tests the hypothesis that target-derived vascular endothelial growth factor (VEGF) promotes sympathetic innervation of blood vessels. Western blot and immunohistochemical analyses indicate that VEGF is produced by vascular cells in arteries and that VEGF receptors are expressed on sympathetic nerve fibers innervating arteries. In vitro, exogenously added VEGF and VEGF produced by vascular smooth muscle cells (VSMCs) in sympathetic neurovascular cocultures inhibited semaphorin 3A (Sema3A)-induced collapse of sympathetic growth cones. In the absence of Sema3A, VEGF and VSMCs also increased growth cone area. These effects were mediated via VEGF receptor 1. In vivo, the neutralization of VEGF inhibited the reinnervation of denervated femoral arteries. These data demonstrate that target-derived VEGF plays a previously unrecognized role in promoting the growth of sympathetic axons.
Chronic β2-adrenoceptor stimulation impairs cardiac relaxation via reduced SR Ca2+-ATPase protein and activity
Authors: Ryall James G. , Schertzer Jonathan D. , Murphy Kate T. , Allen Andrew M. , Lynch Gordon S.
Published: April 2008

We determined the cardiovascular effects of chronic β2-adrenoceptor (β2-AR) stimulation in vivo and examined the mechanism for the previously observed prolonged diastolic relaxation. Rats (3 mo old; n = 6), instrumented with implantable radiotelemeters, received the selective β2-AR agonist formoterol (25 μg·kg−1·day−1ip) for 4 wk, with selected cardiovascular parameters measured daily throughout this period, and for a further 7 days after cessation of treatment. Chronic β2-AR stimulation was associated with an increase in heart rate (HR) of 17% ( days 1– 14) and 5% ( days 15–28); a 11% ( days 1– 14) and 6% ( days 15– 28) decrease in mean arterial blood pressure; and a 24% ( days 1– 14) increase in the rate of cardiac relaxation (−dP/d t) compared with initial values ( P < 0.05). Cessation of β2-AR stimulation resulted in an 8% decrease in HR and a 7% decrease in −dP/d t, compared with initial values ( P < 0.05). The prolonged cardiac relaxation with chronic β2-AR stimulation was associated with a 30% decrease in the maximal rate ( Vmax) of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) activity, likely attributed to a 50% decrease in SERCA2a protein ( P < 0.05). glycogen synthase kinase-3β (GSK-3β) has been implicated as a negative regulator of SERCA2 gene transcription, and we observed a ∼60% decrease ( P < 0.05) in phosphorylated GSK-3β protein after chronic β2-AR stimulation. Finally, we found a 40% decrease ( P < 0.05) in the mRNA expression of the novel A kinase anchoring protein AKAP18, also implicated in β2-AR-mediated cardiac relaxation. These findings highlight some detrimental cardiovascular effects of chronic β2-AR agonist administration and identify concerns for their current and future use for treating asthma or for conditions where muscle wasting and weakness are indicated.
Incidence of protein on actin bridges between endothelium and smooth muscle in arterioles demonstrates heterogeneous connexin expression and phosphorylation
Authors: Isakson Brant E. , Best Angela K. , Duling Brian R.
Published: April 2008

Although much physiology in resistance vessels has been attributed to the cytoplasmic connection between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), little is known of the protein expression between the two cell types. In an attempt to identify the proteins between ECs and VSMCs, mouse cremaster arterioles were stained with phalloidin-Alexa 594 and viewed on a confocal microscope that resolved “actin bridges” within the internal elastic lamina between ECs and VSMCs. To determine the incidence of protein, the pixel intensity from the antibodies on actin bridges were compared with the pixel intensity from antibodies within ECs or VSMCs. N-cadherin, desmin, connexin (Cx)40, and Cx43 and phosphorylated Cx43 at serine-368 were identified on actin bridges, but NG2, CD31, and Cx45 were not evident. Cx37 expression was more variable than the other connexins examined. Using this method on rat mesentery, we confirm the previously published predominance of Cx37 and Cx40 at the myoendothelial junction that was determined using electron microscopy. We conclude that this new method represents an important screening mechanism in which to rapidly test for protein expression between ECs and VSMCs and possibly a first-step in quantifying protein expression at the myoendothelial junction.
Impaired relaxation is the main manifestation in transgenic mice expressing a restrictive cardiomyopathy mutation, R193H, in cardiac TnI
Authors: Du Jianfeng , Liu Jing , Feng Han-Zhong , Hossain M. M. , Gobara Nariman , Zhang Chi , Li Yuejin , Jean-Charles Pierre-Yves , Jin Jian-Ping , Huang Xu-Pei
Published: April 2008

Transgenic mice were generated to express a restrictive cardiomyopathy (RCM) human cardiac troponin I (cTnI) R192H mutation in the heart (cTnI193Hismice). The objective of this study was to assess cardiac function during the development of diastolic dysfunction and to gain insight into the pathophysiological impact of the RCM cTnI mutation. Cardiac function and pathophysiological changes were monitored in cTnI193Hismice and wild-type littermates for a period of 12 mo. It progressed gradually from abnormal relaxation to diastolic dysfunction characterized with high-resolution echocardiography by a reversed E-to-A ratio, increased deceleration time, and prolonged isovolumetric relaxation time. At the age of 12 mo, cardiac output in cTnI193Hismice was significantly declined, and some transgenic mice showed congestive heart failure. The negative impact of cTnI193Hison ventricular contraction and relaxation was further demonstrated in isolated mouse working heart preparations. The main morphological change in cTnI193Hismyocytes was shortened cell length. Dobutamine stimulation increased heart rate in cTnI193Hismice but did not improve CO. The cTnI193Hismice had a phenotype similar to that in human RCM patients carrying the cTnI mutation characterized morphologically by enlarged atria and restricted ventricles and functionally by diastolic dysfunction and diastolic heart failure. The results demonstrate a critical role of the COOH-terminal domain of cTnI in the diastolic function of cardiac muscle.
Transgenic expression of matrix metalloproteinase-9 causes adult-onset emphysema in mice associated with the loss of alveolar elastin
Authors: Foronjy Robert , Nkyimbeng Takwi , Wallace Alison , Thankachen Jincy , Okada Yasunori , Lemaitre Vincent , D'Armiento Jeanine
Published: April 2008

Matrix metalloproteinase (MMP)-9 has been consistently identified in the lungs of patients with chronic obstructive pulmonary disease (COPD). However, its role in the development of the disease remains undefined. Mice that specifically express human MMP-9 in their macrophages were generated, and morphometric, biochemical, and histological analyses were conducted on the transgenic and littermate control mice over 1 yr to determine the effect of macrophage MMP-9 expression on emphysema formation and lung matrix content. Lung morphometry was normal in transgenic mice at 2 mo of age (mean linear intercept = 50 ± 3 littermate mice vs. 51 ± 2 transgenic mice). However, after 12 mo of age, the MMP-9 transgenic mice developed significant air space enlargement (mean linear intercept = 53 ± 3 littermate mice vs. 61 ± 2 MMP-9 transgenic mice; P < 0.04). Lung hydroxyproline content was not significantly different between wild-type and transgenic mice, but MMP-9 did significantly decrease alveolar wall elastin at 1 yr of age (4.9 ± 0.3% area of alveolar wall in the littermate mice vs. 3.3 ± 0.3% area of alveolar wall in the MMP-9 mice; P < 0.004). Thus these results establish a central role for MMP-9 in the pathogenesis of this disease by demonstrating that expression of this protease in macrophages can alter the extracellular matrix and induce progressive air space enlargement in mice.
Evidence for Connections Between Prosecutor-Reported Marijuana Case Dispositions and Community Youth Marijuana-Related Attitudes and Behaviors
Authors: Terry-McElrath Yvonne M. , McBride Duane C. , Chriqui Jamie F. , O'Malley Patrick M. , VanderWaal Curtis J. , Chaloupka Frank J. , Johnston Lloyd D.
Published: April 2008

This article examines relationships between local drug policy (as represented by prosecutor-reported case outcomes for first-offender juvenile marijuana possession cases) and youth self-reported marijuana use, perceived risk, and disapproval. Interviews with prosecutors and surveys of 8th-, 10th-, and 12th-grade students in the United States were conducted in 2000. Analyses include data from 97 prosecutors and students from 127 schools in 40 states. Results indicate significant relationships between local drug policy and youth marijuana use and attitudes. In general, more-severe dispositions are associated with less marijuana use, higher disapproval rates, and increased perceptions of great risk. Associations primarily appear to be specific to marijuana-related outcomes. Results are discussed within the framework of both deterrence and broader social norms regarding substance use.
Depressive Symptoms in Four Racial and Ethnic Groups
Authors: Yuri Jang  , Chiriboga David A. , Kim Giyeon , Phillips Karon
Published: April 2008

Responding to the need for research on the mental health of minority elders, the present study explored determinants of depressive symptoms using a statewide sample of African Americans, Cubans, non-Cuban Hispanics, and Whites from the Survey of Older Floridians. The investigators focused on direct and interactive effects of demographic variables and stressful life conditions (chronic health conditions, functional disability, and negative life events) on depressive symptoms. A hierarchical regression model showed that lower income, more chronic health conditions, greater disability, and more life events were common risk factors for depressive symptoms across all groups. The impacts of age and education were found to be group specific. Significant interactions were also obtained among predictor variables in each group, identifying risk-reducing and risk-enhancing factors within each group. The findings on race-specific risk factors and within-group variability should be taken into consideration when developing and implementing services for diverse older populations.
Planning for End-of-Life Care
Authors: Gerst Kerstin , Burr Jeffrey A.
Published: April 2008

The authors examined Black-White differences in the likelihood of completing written advance directives for end-of-life health care and engaging in informal verbal communication about advanced wishes. Data from the 1998 Health and Retirement Study (HRS) were combined with data from the 2000 HRS exit interview to analyze Black and White participants' completion rates. Whites were more likely than Blacks to grant durable power of attorney for health care, to complete a written will, and to informally communicate their wishes; group differences remained after controlling for personal characteristics. Also, Blacks were less likely than Whites to engage in more than one form of end-of-life planning. The authors speculate that sociocultural differences in trust in the medical system and knowledge about advance directives may partially account for these findings. The findings may aid policy makers and practitioners in increasing the level of participation in advance directives.
The Familial Relationships of Former Prisoners
Authors: Martinez Damian J. , Christian Johnna
Published: April 2008

Former prisoners face tremendous challenges on release from prison— particularly in their reintegration into family relationships. The research evidence indicates that family support is essential to avoid reincarceration. Little is known, however, about what occurs in these relationships, specifically how support is exchanged, why it facilitates success, and which types of support are meaningful. This article examines how former prisoners and their family members exchange supports within two contexts—residence with a family member and residence in a halfway house—and how those supports affect the family relationship. Data were gathered through in-depth interviews with six dyads of former prisoners and family members. The findings indicate that former prisoners' and family members' perceptions and actual exchanges of informal support differ according to the former prisoner's residence, suggesting that residential context is an important aspect in identifying support mechanisms and facilitating former prisoners' resettlement into, and renegotiation of, family relationships.
Intrahospital Correlation of the International Normalized Ratio
Authors: Lazo-Langner Alejandro , Villa-Márquez Rosario , Hernández-Hernández Darinel , Rojas-Maya Sonia , Piedras Josefa
Published: April 2008

Background. Monitoring of oral anticoagulant therapy (OAT) is usually accomplished by measuring prothrombin time and the international normalized ratio (INR). However, thromboplastins have different responsiveness and sensitivity to vitamin K—dependent coagulation factors depletion. Several studies have shown INR variation when low sensitive thromboplastins are used. This study compared INR variability between two laboratories using highly sensitive thromboplastins. Methods. A total of 237 plasmas were tested, half of them from patients under OAT. Samples were tested simultaneously in two laboratories: in laboratory A, a Behring Coagulation Timer instrument and a human recombinant thromboplastin (Innovin, Dade Behring) (ISI 1.01) were used. In laboratory B, a Thrombolyzer Compact (Behnk Elektronik) and a rabbit brain thromboplastin (Simplastin Excel S, Organon Teknika) with an ISI of 1.30 were used. Statistical analysis was carried out according to the method of Bland and Altman. Results. Even though high correlation coefficients were obtained when comparing both laboratories, Bland—Altman analysis showed a variation of INR between laboratories ranging from −0.77 to +1.07. After logarithmic transformation of data, these values yielded a variation of the INR either 25% below or 44% above. Conclusions. These results are clearly inadequate for clinical use because such a variation would most probably induce the clinician to make a change in warfarin dose. Standardization of instruments, reagents, and controls is warranted to decrease this variation.
Treatment Outcome and Criminal Offending by Youth With Sexual Behavior Problems
Authors: Letourneau Elizabeth J. , Chapman Jason E. , Schoenwald Sonja K.
Published: April 2008

Children and adolescents treated for general delinquency problems and rated by caregivers as having sexual behavior problems (SBP; N = 696) were compared with youth from the same sample with no sexual behavior problems (NSBP; N = 1,185). Treatment outcome through 12-months posttreatment and criminal offending through an average 48-month posttreatment were compared for both groups. It was hypothesized that both groups would improve over time; however, the SBP group would evidence greater psychopathology at follow-up, and these hypotheses were supported. It was further hypothesized that youth with SBP would not differ from youth with NSBP in rates of future sexual or nonsexual offenses. These hypotheses were also supported. SBP group membership was not a significant predictive factor in analyses modeling future offending (any) or future person offenses. Few youth in either group had sexual offenses. The importance of these findings for clinical and policy decision making is discussed.
Meta-Analysis of Treatment for Child Sexual Behavior Problems: Practice Elements and Outcomes
Authors: St. Amand Annick , Bard David E. , Silovsky Jane F.
Published: April 2008

This meta-analysis of 11 treatment outcome studies evaluated 18 specific treatments of sexual behavior problems (SBP) as a primary or secondary target. Specifically, it examines relations among child characteristics, treatment characteristics (including practice elements), and short-term outcome (including sexual and general behavior problems). Utilizing pre- and postintervention results, the overall degree of change over the course of treatment was estimated at a 0.46 and 0.49 standard deviation decline in SBP and general behavior problems, respectively. As hypothesized, the caregiver practice element Parenting/Behavior Management Skills (BPT) predicted the Child Sexual Behavior Inventory (and the Child Behavior Checklist when BPT was combined with caregiver Rules about Sexual Behaviors). In contrast, practice elements that evolved from Adult Sex Offender (ASO) treatments were not significant predictors. BPT and preschool age group provided the best model fit and more strongly predicted outcome than broad treatment type classifications (e.g., Play Therapy or Cognitive Behavior Therapy). Results question current treatments for children with SBP that are based on ASO models of treatment without caregiver involvement.
Predictors of Problematic Sexual Behavior Among Children With Complex Maltreatment Histories
Authors: Tarren-Sweeney Michael
Published: April 2008

Exploratory analyses of sexual behavior problems (SBP) were conducted within a larger epidemiological study of 347 preadolescent children in foster and kinship care. SBP was estimated from carergiver-reported scores on the Assessment Checklist for Children. The study simultaneously examined a large number of discrete and cumulative influences on the development of children at high risk for SBP. Most children with SBP had corresponding psychopathology, most notably conduct problems, inattention, and interpersonal behavior problems suggestive of attachment disturbances. Several correlates identified in previous studies were not associated with SBP. High concordance of SBP was found among 52 sibling dyads. Independent predictors of SBP were older age at entry into care, female gender, placement instability, and contact sexual abuse. The findings emphasize the significance of cumulative risk among children exposed to multiple adversities. The findings generated several hypothesized mechanisms involving attachment disturbances.
Gentrification and the Racialized Geography of Home Equity
Authors: Glick Jonathan
Published: April 2008

This article presents an exploration of how gentrification is restructuring racial disparity in home equity building across several U.S. metropolitan areas. I reveal some ways in which gentrification is affecting the relative wealth levels of Black and Latino homeowners, a historically marginalized segment of the housing market. The most common trajectory involves a relatively high concentration of Black and Latino homeowners at the onset of gentrification, increased median levels of home equity for these homeowners as gentrification proceeds, and a relatively high attrition to other parts of the metropolitan area over time. The results suggest that although Black and Latino homeowners can reap financial benefit from gentrification, gentrification encourages net migration toward other parts of the metropolitan area where home equity gains are lower.
Gene expression analysis of interferon-β treatment in multiple sclerosis
Authors: Sellebjerg F , Datta P , Larsen J , Rieneck K , Alsing I , Oturai A , Svejgaard A , Soelberg Sørensen P , Ryder LP
Published: April 2008

Treatment with interferon-β (IFN-β) induces the expression of hundreds of genes in blood mononuclear cells, and the expression of several genes has been proposed as a marker of the effect of treatment with IFN-β. However, to date no molecules have been identified that are stably induced by treatment with IFN-β. We use DNA microarrays to study gene expression in 10 multiple sclerosis (MS) patients who began de novo treatment with IFN-β. After the first injection of IFN-β, the expression of 74 out of 3428 genes changed at least two-fold and statistically significantly (after Bonferroni correction). In contrast, we observed no persisting effects of IFN-β on gene expression. Among the most strongly induced genes was MXA, which has been used in previous biomarker studies in MS. In addition, the study identified the induction of LGALS9 and TCIR1G, involved in negative regulation of T helper type I immunity and T-cell activation, as novel effects of IFN-β therapy in MS.
Process and Impact Evaluation of a Legal Assistance and Health Care Community Partnership
Authors: Teufel James A. , Brown Stephen L. , Thorne Woody , Goffinet Diane M. , Clemons Latesha
Published: April 2008

Community health partnerships have increased in popularity, but their effectiveness is often not evaluated. Through secondary data analysis, this study evaluates a program that offered access to legal services to address health-related issues, such as Medicaid reimbursement, Social Security benefits, medication coverage, and divorce. Based on the analysis reimbursements to expenditures, the health and law program appears to be cost-effective and thereby economically sustainable. The cost-effectiveness of this program increases the likelihood that it will be institutionalized and/or expanded. This program evaluation is used to exemplify how community stakeholders could partner to leverage resources to establish a sustainable community health and law program to address the needs of people living in medically underserved areas.
An essential role for SRC-activated STAT-3 in 14,15-EET–induced VEGF expression and angiogenesis
Authors: Cheranov Sergey Y. , Karpurapu Manjula , Wang Dong , Zhang Baolin , Venema Richard C. , Rao Gadiparthi N.
Published: April 2008

To understand the molecular mechanisms underlying 14,15-epoxyeicosatrienoic acid (14,15-EET)–induced angiogenesis, here we have studied the role of signal transducer and activator of transcription-3 (STAT-3). 14,15-EET stimulated the tyrosine phosphorylation of STAT-3 and its translocation from the cytoplasm to the nucleus in human dermal microvascular endothelial cells (HDMVECs). Adenovirus-mediated delivery of dominant negative STAT-3 substantially inhibited 14,15-EET–induced HDMVEC migration, and tube formation and Matrigel plug angiogenesis. 14,15-EET activated Src, as measured by its tyrosine phosphorylation and blockade of its activation by adenovirus-mediated expression of its dominant negative mutant, significantly attenuated 14,15-EET–induced STAT-3 phosphorylation in HDMVECs and the migration and tube formation of these cells and Matrigel plug angiogenesis. 14,15-EET induced the expression of vascular endothelial cell growth factor (VEGF) in a time- and Src-STAT-3–dependent manner in HDMVECs. Transfac analysis of VEGF promoter revealed the presence of STAT-binding elements and 14,15-EET induced STAT-3 binding to this promoter in vivo, and this interaction was inhibited by suppression of Src-STAT-3 signaling. Neutralizing anti-VEGF antibodies completely blocked 14,15-EET–induced HDMVEC migration and tube formation and Matrigel plug angiogenesis. These results reveal that Src-dependent STAT-3–mediated VEGF expression is a major mechanism of 14,15-EET–induced angiogenesis.
Activation-induced NKT cell hyporesponsiveness protects from α-galactosylceramide hepatitis and is independent of active transregulatory factors
Authors: Biburger Markus , Tiegs Gisa
Published: April 2008

NK T (NKT) cells, unique lymphocytes expressing features of NK and T lymphocytes, can specifically be activated with the glycolipid antigen α-galactosylceramide (α-GalCer). In humans and mice, this activation provokes pronounced cytokine responses. In C57BL/6 mice, α-GalCer injection additionally induces NKT-mediated liver injury, representing a model for immune-mediated hepatitis in humans. However, a single α-GalCer pretreatment of mice prevented NKT-mediated liver injury, cytokine responses (systemically and locally in the liver), and up-regulation of hepatocellular Fas upon α-GalCer rechallenge. As α-GalCer is used as a NKT cell-activating agent in clinical trials, an investigation of tolerance induction appears crucial. We demonstrate that α-GalCer tolerance does not depend on Kupffer cells, IL-10, Caspase-3-mediated apoptosis, or CD4+CD25+ T regulatory cells (Tregs), which are crucial in other models of immunological tolerance. Amending relevant, earlier approaches of others, we cocultivated highly purified, nontolerized and tolerized liver NKT cells ex vivo and could convincingly exclude the relevance of transdominant NKT Tregs. These results strongly suggest α-GalCer-induced tolerance to be exclusively caused by NKT cell intrinsic hyporesponsiveness. Tolerized mice showed specific diminishment of the intrahepatic CD4+ NKT cell subpopulation, with the CD4− population largely unaffected, and revealed down-modulation of α-GalCer-specific TCR and the NKT costimulator glucocorticoid-induced TNFR-related protein on liver NKT cells, whereas inhibitory Ly49I was increased. In conclusion, α-GalCer tolerance could serve as a model for the frequently observed NKT cell hyporesponsiveness in tumor patients and might help to develop strategies for their reactivation. Conversely, approaches to render NKT cells hyporesponsive may constitute new therapeutic strategies for diseases, where aberrant NKT cell activation is causally involved.
Feline vaccine-associated fibrosarcoma induced by aluminium compound in two cats: Short communication
Authors: Deim Zoltán , Pálmai Nimród , Cserni Gábor
Published: April 2008

Two cases of feline vaccine-associated fibrosarcoma (FVAF) are reported. The excised tumours were both characterised as well circumscribed, subcutaneous, firm and white with central necrosis. Histopathologically, they consisted of well-differentiated and variably sized and shaped anaplastic cells, characterised by marked nuclear and cellular pleomorphism including giant cells. The mitotic activity was low. Aluminium was demonstrated in the central necrosis and giant cells. Neoplastic cells were positive for vimentin and negative for desmin and cytokeratin. The presence of feline sarcoma virus and feline immunodeficiency virus could not be detected by PCR in either case.
Immunohistochemical distribution of alpha B-crystallin in the cerebellum of dogs infected with canine distemper virus
Authors: Guvenc Tolga , Yarim Murat , Gulbahar Mustafa , Kabak Yonca
Published: April 2008

The cerebella of 12 dogs infected with canine distemper virus (CDV) and those of three normal dogs were examined. The avidin-biotin-peroxidase complex technique was used to detect αB-crystallin (αB-c) immunoreactivity and immunolocalisation of the CDV antigen. CDV antigens, immunopositive astrocytes, oligodendrocytes and granular neurons were seen in both the white and grey matter of the infected dogs. In the controls, αB-c immunopositive glial cells were seen in the white matter and around the Purkinje cells. In dogs with distemper, αB-c immunoreactivity was not observed in some of the glial cells around the Purkinje cells. A significant negative correlation of P < 0.01 level was found between areas of severe demyelination and the number of αB-c immunopositive cells in dogs infected with CDV. Such correlation was not observed between mild and moderate demyelinating areas and αB-c immunostaining. The αB-crystallin/total number of cells ratio was found to be significant in severely affected demyelinating areas (P < 0.05). These data indicate that there was a relationship between the degrees of CDV associated with demyelination and the level of αB-c expression in the glial cells.
Melengestrol acetate as a tool for inducing early ovulation in transitional mares
Authors: López-Bayghen Consuelo , Zozaya Heidy , Ocampo Luis , Brumbaugh Gordon , Sumano Héctor
Published: April 2008

The efficacy of melengestrol acetate (MGA) to shorten the vernal transition of mares by synchronising and accelerating the first ovulation of the year after 60 days of phototherapy was determined by ultrasonographic monitoring. Sixteen mares in late transition were fed two doses of MGA (150 mg/mare/day and 100 mg/mare/day, respectively) for 10 days. A luteolytic dose of prostaglandin was administered to each mare one day after the end of MGA treatment. The presence and duration of oestrus, follicular growth, uterine oedema and presence of ovulation were monitored by ultrasonography and the cervical tone was evaluated by rectal palpation. Ovulation was detected in 87.5% of the mares treated with 150 mg MGA/mare/day for 10 days, and in 62.5% of the mares receiving 100 mg MGA/mare/day for 10 days. This was statistically different (P = 0.03) from the untreated control mares having an ovulation rate of 20%. Mares that received 150 mg MGA/day for 10 days had a mean treatment to ovulation interval of 13.1 ± 5.97 days after the end of treatment, while mares that received 100 mg MGA/day for 10 days had a mean of 25.6 ± 10.50 days (P = 0.01) to ovulation. These results suggest that MGA can be used for synchronising and hastening the first ovulation of the year in mares.