bluuebunny/crossref_metadata_2025 huggingface dataset:
Decoration ofPasteurella multocidaLipopolysaccharide with Phosphocholine Is Important for Virulence
Authors: Harper Marina , Cox Andrew , St. Michael Frank , Parnas Henrietta , Wilkie Ian , Blackall P. J. , Adler Ben , Boyce John D.
Published: August 2007

Phosphocholine (PCho) is an important substituent of surface structures expressed by a number of bacterial pathogens. Its role in virulence has been investigated in several species, in which it has been shown to play a role in bacterial adhesion to mucosal surfaces, in resistance to antimicrobial peptides, or in sensitivity to complement-mediated killing. The lipopolysaccharide (LPS) structure ofPasteurella multocidastrain Pm70, whose genome sequence is known, has recently been determined and does not contain PCho. However, LPS structures from the closely related, virulentP. multocidastrains VP161 and X-73 were shown to contain PCho on their terminal galactose sugar residues. To determine if PCho was involved in the virulence ofP. multocida, we used subtractive hybridization of the VP161 genome against the Pm70 genome to identify a four-gene locus (designatedpcgDABC) which we show is required for the addition of the PCho residues to LPS. The proteins predicted to be encoded bypcgABCshowed identity to proteins involved in choline uptake, phosphorylation, and nucleotide sugar activation of PCho. We constructed aP. multocidaVP161pcgCmutant and demonstrated that this strain produces LPS that lacks PCho on the terminal galactose residues. ThispcgCmutant displayed reduced in vivo growth in a chicken infection model and was more sensitive to the chicken antimicrobial peptide fowlicidin-1 than the wild-typeP. multocidastrain.
Influence of the Hydrodynamic Environment on Quorum Sensing in
Pseudomonas aeruginosa
Biofilms
Authors: Kirisits Mary Jo , Margolis Jeffrey J. , Purevdorj-Gage Boloroo L. , Vaughan Benjamin , Chopp David L. , Stoodley Paul , Parsek Matthew R.
Published: August 2007

We provide experimental and modeling evidence that the hydrodynamic environment can impact quorum sensing (QS) in a
Pseudomonas aeruginosa
biofilm. The amount of biofilm biomass required for full QS induction of the population increased as the flow rate increased.
Severe Gastroenteritis and Hypovolemic Shock Caused by
Grimontia
(
Vibrio
)
hollisae
Infection
Authors: Hinestrosa Federico , Madeira Robert G. , Bourbeau Paul P.
Published: August 2007

Vibrio hollisae
is a halophilic species that was recently reclassified as
Grimontia hollisae
. This organism is known to cause moderate to severe cases of gastroenteritis. We report a case of an individual who suffered a more severe form of this disease, presenting with profound hypotension and acute renal failure, secondary to hypovolemic shock.
Activation of Phosphatidylinositol 3-Kinase Signaling by the Nonstructural NS1 Protein Is Not Conserved among Type A and B Influenza Viruses
Authors: Ehrhardt Christina , Wolff Thorsten , Ludwig Stephan
Published: August 2007

Recently it has been shown by several laboratories that the influenza A virus nonstructural protein 1 (A/NS1) binds and activates phosphatidylinositol 3-kinase (PI3K). This function of the protein is likely to prevent premature apoptosis induction during viral propagation. Here we show that the B/NS1 protein completely lacks the capacity to induce PI3K signaling. Thus, PI3K activation is another unique function of A/NS1 that is different from the action of its influenza B virus counterpart.
Capsid Protein-Mediated Recruitment of Host DnaJ-Like Proteins Is Required for
Potato Virus Y
Infection in Tobacco Plants
Authors: Hofius Daniel , Maier Annette T. , Dietrich Christof , Jungkunz Isabel , Börnke Frederik , Maiss Edgar , Sonnewald Uwe
Published: August 2007

The capsid protein (CP) of potyviruses is required for various steps during plant infection, such as virion assembly, cell-to-cell movement, and long-distance transport. This suggests a series of compatible interactions with putative host factors which, however, are largely unknown. By using the yeast two-hybrid system the CP from
Potato virus Y
(PVY) was found to interact with a novel subset of DnaJ-like proteins from tobacco, designated NtCPIPs. Mutational analysis identified the CP core region, previously shown to be essential for virion formation and plasmodesmal trafficking, as the interacting domain. The ability of NtCPIP1 and NtCPIP2a to associate with PVY CP could be confirmed in vitro and was additionally verified in planta by bimolecular fluorescence complementation. The biological significance of the interaction was assayed by PVY infection of agroinfiltrated leaves and transgenic tobacco plants that expressed either full-length or J-domain-deficient variants of NtCPIPs. Transient expression of truncated dominant-interfering NtCPIP2a but not of the functional protein resulted in strongly reduced accumulation of PVY in the inoculated leaf. Consistently, stable overexpression of J-domain-deficient variants of NtCPIP1 and NtCPIP2a dramatically increased the virus resistance of various transgenic lines, indicating a critical role of functional NtCPIPs during PVY infection. The negative effect of impaired NtCPIP function on viral pathogenicity seemed to be the consequence of delayed cell-to-cell movement, as visualized by microprojectile bombardment with green fluorescent protein-tagged PVY. Therefore, we propose that NtCPIPs act as important susceptibility factors during PVY infection, possibly by recruiting heat shock protein 70 chaperones for viral assembly and/or cellular spread.
The squamous variant of eccrine porocarcinoma: a clinicopathological study of 21 cases
Authors: Mahomed F , Blok J , Grayson W
Published: August 2007

Aim:

Squamous differentiation in eccrine porocarcinoma (EPC) is an unusual phenomenon that has rarely been reported in the literature. This study describes the clinical and pathological findings in a series of 21 cases of EPC showing extensive squamous differentiation.

Methods:

The H&E-stained sections, epithelial membrane antigen and carcinoembryonic antigen immunohistochemical stains were reviewed for each case. The following variables were examined: age, gender, race, site and size of the EPC. The prevalence of other cutaneous lesions and/or underlying systemic disease was also documented.

Results:

There was an almost equal gender distribution. Mean age was 61.5 years and the average tumour size was 46.5 mm. An inordinately large number (10/21, 48%) of EPCs occurred in black patients. The tumours were located at various sites with the extremities predominating (10/19, 53%). Seven patients developed other sun-induced skin tumours, three patients were renal transplant recipients, and two patients were HIV-positive, one of whom also suffered from albinism. Six of the 11 patients in whom follow-up was available had an adverse outcome: local recurrence developed in one patient, one patient developed nodal metastases, and one patient experienced both local recurrence and nodal metastases, and of the three patients who died of disease, two developed distant metastases.

Conclusion:

The findings suggest a possible role for ultraviolet radiation and chronic immunosuppression in the induction of malignant squamous differentiation in a subset of EPCs. Further reports on this histological variant of EPC are required to determine whether a pathogenetic link does indeed exist or whether these tumours simply represent a unique variant of squamous cell carcinoma with divergent acrosyringial differentiation.
p53 protein expression and genetic mutation in two primary cell types in pulmonary sclerosing haemangioma
Authors: Wang Y , Dai S-D , Qi F-J , Xu H-T , Wang E-H
Published: August 2007

Aims:

To investigate the significance of p53 protein expression and genetic mutations in two primary cell types in pulmonary sclerosing haemangioma (PSH).

Methods:

p53 protein expression in polygonal cells and cuboidal cells in 19 patients with PSH was detected using immunohistochemistry. The two major cell types were captured using laser capture microdissection technology. Mutations in the p53 gene (exons 5–8) were examined using single-stranded conformation polymorphism and DNA sequencing analysis.

Results:

p53 protein expression and gene mutations were observed in 15.8% (3/19) of cases. In these cases, p53 protein was expressed in the nucleus of both cell types, with higher expression levels and mutation rates in polygonal cells than in surface cuboidal cells. Two cases showed mutation only in the polygonal cells, while one case showed double (separate) mutations in both the polygonal and cuboidal cells.

Conclusions:

p53 mutation was exhibited in PSH. The mutation rate in polygonal cells was higher than that in surface cuboidal cells.
TWO-MODE ENTANGLEMENT VIA SUPERPOSITIONS OF TWO-MODE COHERENT STATES
Authors: PING YUN-XIA , ZHANG BO , CHENG ZE , XU QINFENG
Published: August 2007

Two-mode entanglement of superposition states from several two-mode coherent states is investigated according to the entanglement criterion.9 The dependence of entanglement on relative phase angle, coherent amplitude of each mode and phase angle is discussed. It is shown that under certain conditions the superposition states can exhibit entanglement properties.
ON THE IDEALITY FACTOR OF THE GaAlAs SEMICONDUCTOR DIODE BELOW KNEE VOLTAGE
Authors: OTA S. B. , OTA SMITA
Published: August 2007

We have studied forward characteristics of a GaAlAs diode for various current values, below the knee voltage, in the temperature range 50–300 K. The ideality factor η in the dynamics of minority carrier have been obtained in this temperature range.
RENEWAL PROCESS FOR FUZZY VARIABLES
Authors: HONG DUG HUN
Published: August 2007

Recently, Zhao and Liu [IJUFKS 11 (2003) 573–586] proposed a "fuzzy elementary renewal theorem" and "fuzzy renewal rewards theorem" for a renewal process in which the inter-arrival times and rewards are characterized as continuous fuzzy variables. The continuity assumption is restrictive. In this note, we prove the same results without the assumption of continuity of the inter-arrival times and rewards.
CLASSICAL NOISE INDUCED DECOHERENCE EFFECTS ON THE ENTANGLEMENT IN A TWO-QUBIT SYSTEM
Authors: LASTRA F. , ROMERO G. , LÓPEZ C. E. , RETAMAL J. C.
Published: August 2007

In this work we study entanglement properties of a two-qubit system being affected by a classical noisy environment and coupled through exchange interaction. We study the dynamical generation of entanglement considering different initial conditions for the two-qubit system. We evaluate the rate at which entanglement is lost by calculating the concurrence as a function of time.
VERIFIER-BASED ALGORITHM FOR UNSORTED DATABASE SEARCH PROBLEM
Authors: WU XIAO DI , LONG GUI LU
Published: August 2007

Unsorted database search problem is an important science and engineering problem. We proposed quantum algorithm to solve the problem by dividing the database binarily and then use a probabilistic verifier algorithm to determine if the item is within one part of the divided database. We analyzed the computational complexity of this algorithm, and found that in general, the number of steps is proportional to that in the standard Grover algorithm. However in some cases, it is less than that of the Grover algorithm.
ADOPTION OF INNOVATIVE PRODUCTION TECHNOLOGIES IN THE ROAD CONSTRUCTION INDUSTRY
Authors: HABETS THIJS , VAN DER SIJDE PETER , VOORDIJK HANS
Published: August 2007

New procurement methods encourage the adoption of innovative production technologies. This triggers the need for entrepreneurship in the construction industry. The purpose of this study is to provide insights into the adoption processes of a particular set of new production technologies in the Dutch road construction industry and the factors affecting these processes. An entrepreneurship in networks (EiN) model and the perceived benefits of Rogers are incorporated into one framework. From the total population 55% participated in this study. The results show that 83% of the respondents preferred innovation over no innovation. From the companies that chose to innovate, typically, the smaller companies preferred an architectural — more challenging — innovation.
Short Range Correlation and H-Quantum
Authors: Suzuki Haruo
Published: August 2007

Accelerator data of short range correlation in multiple particle production are investigated through an H-quantum model. The average decay charge multiplicity of an H-quantum is consistently given to be 3∼4 with semi-inclusive correlation data. These values are shown to be compatible with three particle correlation data. Antiproton production is studied and the branching ratio of H-quantum emitting an antiproton is given to be 0.045 ∼0.06. It is pointed out that prominent resonances cannot be candidates for clusters in independent emission models in connection with correlation data of like charge pairs.
EGFR Tyrosine Kinase Inhibitors in Lung Cancer: An Evolving Story
Authors: Sequist Lecia V. , Lynch Thomas J.
Published: August 2007

Drugs that target the epidermal growth factor receptor (EGFR) have had a major impact on the treatment of non–small cell lung cancer (NSCLC). The use of these drugs has also motivated pivotal advances in the understanding of the molecular biology of NSCLC, including the discovery that mutations in EGFR are associated with dramatic and sustained responses to anti-EGFR treatments. This review summarizes the clinical development of EGFR tyrosine kinase inhibitors, the discovery of molecular predictors of response, and the future directions for research in the field.
Monophasic action potentials generated by bidomain modeling as a tool for detecting cardiac repolarization times
Authors: Colli Franzone P. , Pavarino L. F. , Scacchi S. , Taccardi B.
Published: August 2007

Unipolar electrograms (EGs) and hybrid (or unorthodox or unipolar) monophasic action potentials (HMAPs) are currently the only proposed extracellular electrical recording techniques for obtaining cardiac recovery maps with high spatial resolution in exposed and isolated hearts. Estimates of the repolarization times from the HMAP downstroke phase have been the subject of recent controversies. The goal of this paper is to computationally address the controversies concerning the HMAP information content, in particular the reliability of estimating the repolarization time from the HMAP downstroke phase. Three-dimensional numerical simulations were performed by using the anisotropic bidomain model with a region of short action potential durations. EGs, transmembrane action potentials (TAPs), and HMAPs elicited by an epicardial stimulation close or away from a permanently depolarized site were computed. The repolarization time was computed as the moment of EG fastest upstroke (RTeg) during the T wave, of HMAP fastest downstroke (RTHMAP), and of TAP fastest downstroke (RTtap). The latter was taken as the gold standard for repolarization time. We also compared the times (RT90HMAP, RT90tap) when the HMAP and TAP first reach 90% of their resting value during the downstroke. For all explored sites, the HMAP downstroke closely followed the TAP downstroke, which is the expression of local repolarization activity. Results show that HMAP and TAP markers are highly correlated, and both markers RTHMAP and RTeg (RT90HMAP) are reliable estimates of the TAP reference marker RTtap (RT90tap). Therefore, the downstroke phase of the HMAP contains valuable information for assessing repolarization times.
A role for ICAM-1 in maintenance of leukocyte-endothelial cell rolling interactions in inflamed arterioles
Authors: Sumagin Ronen , Sarelius Ingrid H.
Published: August 2007

A key endothelial receptor in leukocyte-endothelial cell (EC) interactions is ICAM-1. ICAM-1 is constitutively expressed at low levels on vascular ECs, and its levels significantly increase following stimulation with many proinflammatory agents. This study provides evidence that in inflamed arterioles of anesthetized mice (65 mg/kg ip Nembutal), ICAM-1 mediates leukocyte rolling, in contrast to its expected role of mediating firm adhesion in venules. The number of leukocytes rolling on arteriolar ECs is decreased in ICAM-1 knockout (KO) compared with wild-type (WT) mice (KO, 6.0 ± 0.9; WT, 12.0 ± 1.0 leukocytes/40 s; P < 0.05), whereas the leukocyte-rolling number in venules remains unaffected (KO, 5.6 ± 0.9; WT, 7.0 ± 0.7 leukocytes/40 s; n = 13–15 sites). We also show that the fraction of leukocytes that is rolling on arteriolar ECs does so with a higher characteristic velocity (>70 μm/s), and, furthermore, that the distance over which rolling contacts with the arteriolar wall are maintained is ICAM-1 dependent. In ICAM-1 KO animals or in WT mice in the presence of ICAM-1-blocking antibody, leukocytes rolled significantly shorter distances over the sampled 200-μm vessel length compared with WT (68 ± 6.7 and 55 ± 9.4 vs. 85 ± 12.9% total, respectively, n = 4 sites, P < 0.05). We also found evidence that in ICAM-1 KO mice, a significant fraction of leukocyte rolling and adhesive interactions with arteriolar ECs could be accounted for by upregulation of another adhesion molecule, VCAM-1, providing an important illustration of how expression of related proteins can be altered following genetic ablatement of a target molecule (in this case ICAM-1).
Mechanisms of action of the congenital diaphragmatic hernia-inducing teratogen nitrofen
Authors: Noble B. Rhiannon , Babiuk Randal P. , Clugston Robin D. , Underhill T. Michael , Sun Hui , Kawaguchi Riki , Walfish Paul G. , Blomhoff Rune , Gundersen Thomas E. , Greer John J.
Published: August 2007

Congenital diaphragmatic hernia (CDH) is a developmental anomaly that results in significant mortality and morbidity. The underlying etiology is poorly understood. Insights will arise from an understanding of the mechanisms by which the teratogen nitrofen induces CDH in rodent models. In this study, we use in vitro cell assays in conjunction with whole animal rodent studies to test hypotheses regarding nitrofen's mechanism of action. The first component examined the interaction of nitrofen with various aspects of the retinoid signaling pathway including uptake proteins, binding proteins, receptors, conversion, and degradation enzymes. The second component examined the interactions of nitrofen and vitamins A, C, and E to test the hypothesis that nitrofen was functioning as an antioxidant to interfere with retinoid signaling. Third, we performed a series of experiments examining the interaction of nitrofen and thyroid signaling. Collectively, the data suggest that the primary aspect of retinoid signaling affected by nitrofen is via inhibition of the rate-limiting enzymes controlling retinoic acid synthesis. Retinoid signaling perturbations do not appear to involve oxidative effects of nitrofen. Any substantial roles of nitrofen-induced perturbations of thyroid hormone signaling or receptor function are not supported.
Right ventricular TNF resistance during endotoxemia: the differential effects on ventricular function
Authors: Markel Troy A. , Crisostomo Paul R. , Wang Meijing , Herrmann Jeremy L. , Abarbanell Aaron M. , Meldrum Daniel R.
Published: August 2007

Right and left ventricular myocytes originate from different cellular progenitors; however, it is unknown whether these cells differ in their response to endotoxemia. We hypothesized that 1) the percentage of endotoxemic functional depression within the right ventricle (RV) would be smaller than that of the left ventricle; and 2) that better RV function would correlate with lower levels of right ventricular TNF production. Adult Sprague-Dawley rats were divided into right and left control and endotoxin groups. Controls received vehicle, while endotoxin groups received LPS at 20 mg/kg ip. Hearts were excised either 2 or 6 h after injection. Hearts excised at 2 h were assayed for TNF, IL-6, TNF receptor 1 (TNFR1), TNFR2, and via ELISA, while hearts excised at 6 h were assayed via the Langendorff model. The percentage of cardiac functional depression, exhibited as developed pressure, contractility, and rate of relaxation (expressed as a percentage of control) was significantly smaller in right ventricles compared with left ventricles following endotoxin exposure. Tissue levels of TNF were significantly elevated in both right and left ventricles 2 h after endotoxin exposure, and right ventricular endotoxin groups expressed higher levels of TNF compared with their left ventricular counterparts. No significant differences in IL-6, TNFR1, or TNFR2 levels were noted between endotoxin-exposed ventricles. This is the first study to demonstrate that right and left ventricular function differs after endotoxin exposure.
Autonomic nervous nonlinear interactions lead to frequency modulation between low- and high-frequency bands of the heart rate variability spectrum
Authors: Zhong Yuru , Bai Yan , Yang Bufan , Ju Kihwan , Shin Kunsoo , Lee Myoungho , Jan Kung-Ming , Chon Ki H.
Published: August 2007

Cardiac sympathetic and parasympathetic neural activities have been found to interact with each other to efficiently regulate the heart rate and maintain homeostasis. Quantitative and noninvasive methods used to detect the presence of interactions have been lacking, however. This may be because interactions among autonomic nervous systems are nonlinear and nonstationary. The goal of this work was to identify nonlinear interactions between the sympathetic and parasympathetic nervous systems in the form of frequency and amplitude modulations in human heart rate data. To this end, wavelet analysis was performed, followed by frequency analysis of the resultant wavelet decomposed signals in several frequency brackets defined as very low frequency ( f < 0.04 Hz), low frequency (LF; 0.04–0.15 Hz), and high frequency (HF; 0.15–0.4 Hz). Our analysis suggests that the HF band is significantly modulated by the LF band in the heart rate data obtained in both supine and upright body positions. The strength of modulations is stronger in the upright than supine position, which is consistent with elevated sympathetic nervous activities in the upright position. Furthermore, significantly stronger frequency modulation than in the control condition was also observed with the cold pressor test. The results with the cold pressor test, as well as the body position experiments, further demonstrate that the frequency modulation between LF and HF is most likely due to sympathetic and parasympathetic nervous interactions during sympathetic activations. The modulation phenomenon suggests that the parasympathetic nervous system is frequency modulated by the sympathetic nervous system. In this study, there was no evidence of amplitude modulation among these frequencies.
Elevated phosphorus modulates vitamin D receptor-mediated gene expression in human vascular smooth muscle cells
Authors: Wu-Wong J. Ruth , Nakane Masaki , Ma Junli , Ruan Xiaoan , Kroeger Paul E.
Published: August 2007

Clinical observations show that an increase in serum inorganic phosphorus (Pi) is linked to higher cardiovascular (CV) mortality, while vitamin D receptor (VDR) agonist therapy is associated with survival benefit in stage 5 chronic kidney disease. Smooth muscle cells (SMCs) play an important role in CV pathophysiology, but the interaction between Pi and the VDR signaling pathway in SMCs is not known. Real-time RT-PCR studies revealed that elevated Pi (2.06 mM) modulated VDR-mediated regulation of a panel of genes including thrombomodulin and osteopontin in SMCs. DNA microarray results demonstrated that increasing Pi from 0.9 to 2.06 mM exerted a widespread modulating effect on VDR-mediated gene expression. A total of 325 target genes were affected by paricalcitol at 0.9 mM Pi, with 195 up- and 130 downregulated. The number of target genes affected by paricalcitol at 2.06 mM Pi decreased to 86, with 55 up- and 31 downregulated. VDR-mediated gene expression in As4.1 cells (a juxtaglomerular cell-like cell line derived from kidney tumors in SV40 T-antigen transgenic mice) and peroxisome proliferator-activated receptor (PPAR)γ-mediated gene expression in SMCs were also altered by elevated Pi, suggesting that the observation is not unique to VDR in SMCs. Mechanism analysis showed that elevated Pi had no significant effect on VDR or PPARγ protein level but altered the cytosolic vs. nuclear distribution of NF-κB or nuclear receptor corepressor 1 (NCoR1). Our results demonstrate for the first time that elevated Pi affects VDR-mediated gene expression in human coronary artery SMCs and the effect is not limited to VDR in SMCs.
Regional Specification of Threshold Sensitivity and Response Time in CBA/CaJ Mouse Spiral Ganglion Neurons
Authors: Liu Qing , Davis Robin L.
Published: August 2007

Previous studies of spiral ganglion neuron electrophysiology have shown that specific parameters differ according to cochlear location, with apical neurons being distinctly different from basal neurons. To align these features more precisely along the tonotopic axis of the cochlea, we developed a novel spiral ganglion culture system in which positional information is retained. Patch-clamp recordings made from neurons of known gangliotopic location revealed two basic firing pattern distributions. Membrane characteristics related to spike timing, such as accommodation, latency and onset tau, were distinctly heterogeneous, yet when averaged, they were distributed in a graded manner along the length of the cochlea. Action potential threshold levels also displayed a wide range, the averages of which were distributed nonmonotonically such that neurons with the greatest sensitivity were localized to the mid-regions of the ganglion. These studies shed new light on the complexity and sophistication of the intrinsic firing features of spiral ganglion neurons. Because timing-related elements are organized in an overall tonotopic manner, it is hypothesized that they contribute to aspects of frequency-dependent acoustic processing. On the other hand, the different distribution of threshold levels, with the greatest sensitivity in the middle region of the tonotopic map, suggests that this neuronal parameter is regulated differently and thus may contribute a distinct realm of auditory sensory processing.
A Cluster Randomised Controlled Trial to Evaluate the Effectiveness of Fluoride Varnish as a Public Health Measure to Reduce Caries in Children
Authors: Hardman M.C. , Davies G.M. , Duxbury J.T. , Davies R.M.
Published: August 2007

This cluster randomised controlled study assessed the effectiveness of twice-yearly applications of fluoride varnish as a public health measure to reduce dental caries in children living in relatively deprived communities. The test (n = 334) and control (n = 330) children in 2 school years (unit of randomisation) attended 24 state primary schools and were 6–8 years of age at the start. Good baseline balance was found. Duraphat varnish was applied at school on 5 occasions over 26 months, by dental therapists. A combined visual and fibre-optic transillumination examination included all surfaces of primary and first permanent molars at baseline and after 26 months for small and large enamel and dentine lesions. At the final examination the only statistically significant difference was in the caries increment for small enamel lesions in the primary dentition, with the test children having fewer lesions. This study failed to demonstrate that the twice-yearly application of fluoride varnish provided at school reduced dental caries in children living in this community. The low level of response and a lower than expected caries increment had a major impact on the effectiveness of the intervention, since the children who participated were least likely to have benefited from the programme, whereas those who might have benefited did not consent.
Loss of the α7 Integrin Promotes Extracellular Signal-Regulated Kinase Activation and Altered Vascular Remodeling
Authors: Welser Jennifer V. , Lange Naomi , Singer Cherie A. , Elorza Margaret , Scowen Paul , Keef Kathleen D. , Gerthoffer William T. , Burkin Dean J.
Published: August 2007

Vascular smooth muscle cell (VSMC) proliferation and migration are underlying factors in the development and progression of cardiovascular disease. Studies have shown that altered expression of vascular integrins and extracellular matrix proteins may contribute to the vascular remodeling observed after arterial injury and during disease. We have recently shown that loss of the α7β1 integrin results in VSMC hyperplasia. To investigate the cellular mechanisms underlying this phenotype, we have examined changes in cell signaling pathways associated with VSMC proliferation. Several studies have demonstrated the mitogen-activated protein kinase signaling pathway is activated in response to vascular injury and disease. In this study, we show that loss of the α7 integrin in VSMCs results in activation of the extracellular signal-regulated kinase and translocation of the activated kinase to the nucleus. Forced expression of the α7 integrin or use of the mitogen-activated protein kinase kinase 1 inhibitor U0126 in α7 integrin–deficient VSMCs suppressed extracellular signal-regulated kinase activation and restored the differentiated phenotype to α7 integrin–null cells in a manner dependent on Ras signaling. α7 Integrin–null mice displayed profound vascular remodeling in response to injury with pronounced neointimal formation and reduced vascular compliance. These findings demonstrate that the α7β1 integrin negatively regulates extracellular signal-regulated kinase activation and suggests an important role for this integrin as part of a signaling complex regulating VSMC phenotype switching.
Intra–Sarcoplasmic Reticulum Free [Ca
2+
] and Buffering in Arrhythmogenic Failing Rabbit Heart
Authors: Guo Tao , Ai Xun , Shannon Thomas R. , Pogwizd Steven M. , Bers Donald M.
Published: August 2007

Smaller Ca
2+
transients and systolic dysfunction in heart failure (HF) can be largely explained by reduced total sarcoplasmic reticulum (SR) Ca
2+
content ([Ca]
SRT
). However, it is unknown whether low [Ca]
SRT
is manifest as reduced: (1) intra-SR free [Ca
2+
] ([Ca
2+
]
SR
), (2) intra-SR Ca
2+
buffering, or (3) SR volume (as percentage of cell volume). Here we assess these possibilities in a well-characterized rabbit model of nonischemic HF. In HF versus control myocytes, diastolic [Ca
2+
]
SR
is similar at 0.1-Hz stimulation, but the increase in both [Ca
2+
]
SR
and [Ca]
SRT
as frequency increases to 1 Hz is blunted in HF. Direct measurement of intra-SR Ca
2+
buffering (by simultaneous [Ca
2+
]
SR
and [Ca]
SRT
measurement) showed no change in HF. Diastolic [Ca]
SRT
changes paralleled [Ca
2+
]
SR
, suggesting that SR volume is not appreciably altered in HF. Thus, reduced [Ca]
SRT
in HF is associated with comparably reduced [Ca
2+
]
SR
. Fractional [Ca
2+
]
SR
depletion increased progressively with stimulation frequency in control but was blunted in HF (consistent with the blunted force–frequency relationship in HF). By studying a range of [Ca
2+
]
SR
, analysis showed that for a given [Ca]
SR
, fractional SR Ca
2+
release was actually higher in HF. For both control and HF myocytes, SR Ca
2+
release terminated when [Ca
2+
]
SR
dropped to 0.3 to 0.5 mmol/L during systole, consistent with a role for declining [Ca
2+
]
SR
in the dynamic shutoff of SR Ca
2+
release. We conclude that low total SR Ca
2+
content in HF, and reduced SR Ca
2+
release, is attributable to reduced [Ca
2+
]
SR
, not to alterations in SR volume or Ca
2+
buffering capacity.
Regulation of Tetrahydrobiopterin Biosynthesis by Shear Stress
Authors: Widder Julian D. , Chen Wei , Li Li , Dikalov Sergey , Thöny Beat , Hatakeyama Kazuyuki , Harrison David G.
Published: August 2007

An essential cofactor for the endothelial NO synthase is tetrahydrobiopterin (H
4
B). In the present study, we show that in human endothelial cells, laminar shear stress dramatically increases H
4
B levels and enzymatic activity of GTP cyclohydrolase (GTPCH)-1, the first step of H
4
B biosynthesis. In contrast, protein levels of GTPCH-1 were not affected by shear. Shear did not change protein expression or activity of the downstream enzymes 6-pyruvoyl-tetrahydropterin synthase and sepiapterin reductase and decreased protein levels of the salvage enzyme dihydrofolate reductase. Oscillatory shear only modestly affected H
4
B levels and GPTCH-1 activity. We also demonstrate that laminar, but not oscillatory shear stress, stimulates phosphorylation of GTPCH-1 on serine 81 and that this is mediated by the α prime (α′) subunit of casein kinase 2. The increase in H
4
B caused by shear is essential in allowing proper function of endothelial NO synthase because GPTCH-1 blockade with 2,4-diamino-6-hydroxypyrimidine during shear inhibited dimer formation of endothelial NO synthase, increased endothelial cell superoxide production, and prevented the increase in NO production caused by shear. Thus, shear stress not only increases endothelial NO synthase levels but also stimulates production of H
4
B by markedly enhancing GTPCH-1 activity via casein kinase 2–dependent phosphorylation on serine 81. These findings illustrate a new function of casein kinase 2 in the endothelium and provide insight into regulation of GTPCH-1 activity.
Inducible NO Synthase–DependentS-Nitrosylation and Activation of Arginase1 Contribute to Age-Related Endothelial Dysfunction
Authors: Santhanam Lakshmi , Lim Hyun Kyo , Lim Hyun Kyoung , Miriel Victor , Brown Tashalee , Patel Meet , Balanson Sarit , Ryoo Sungwoo , Anderson Mirinda , Irani Kaikobad , Khanday Firdous , Di Costanzo Luigi , Nyhan Daniel , Hare Joshua M. , Christianson David W. , Rivers Richard , Shoukas Artin , Berkowitz Dan E.
Published: August 2007

Endothelial function is impaired in aging because of a decrease in NO bioavailability. This may be, in part, attributable to increased arginase activity, which reciprocally regulates NO synthase (NOS) by competing for the common substrate,l-arginine. However, the highKmof arginase (>1 mmol/L) compared with NOS (2 to 20 μmol/L) seemingly makes direct competition for substrate unlikely. One of the mechanisms by which NO exerts its effects is by posttranslational modification throughS-nitrosylation of protein cysteines. We tested the hypothesis that arginase1 activity is modulated by this mechanism, which serves to alter its substrate affinity, allowing competition with NOS forl-arginine. We demonstrate that arginase1 activity is altered byS-nitrosylation, both in vitro and ex vivo. Furthermore, using site-directed mutagenesis we demonstrate that 2 cysteine residues (C168 and C303) are able to undergo nitrosylation.S-Nitrosylation of C303 stabilizes the arginase1 trimer and reduces itsKmvalue 6-fold. Finally, arginase1 nitrosylation is increased (and thus itsKmdecreased) in blood vessels from aging rats, likely contributing to impaired NO bioavailability and endothelial dysfunction. This is mediated by inducible NOS, which is expressed in the aging endothelium. These findings suggest thatS-nitrosylated arginase1 can compete with NOS forl-arginine and contribute to endothelial dysfunction in the aging cardiovascular system.
The Self-Construction and -Repair of a Foraging Organism by Explicitly Specified Development from a Single Cell
Authors: Roth Fabian , Siegelmann Hava , Douglas Rodney J.
Published: August 2007

As man-made systems become more complex and autonomous, there is a growing need for novel engineering methods that offer self-construction, adaptation to the environment, and self-repair. In a step towards developing such methods, we demonstrate how a simple model multicellular organism can assemble itself by replication from a single cell and finally express a fundamental behavior: foraging. Previous studies have employed evolutionary approaches to this problem. Instead, we aim at explicit design of self-constructing and -repairing systems by hierarchical specification of elementary intracellular mechanisms via a kind of genetic code. The interplay between individual cells and the gradually increasing self-created complexity of the local structure that surrounds them causes the serial unfolding of the final functional organism. The developed structure continuously feeds back to the development process, and so the system is also capable of self-repair.
Computational Realizations of Living Systems
Authors: Chu Dominique , Ho Weng Kin
Published: August 2007

Robert Rosen's central theorem states that organisms are fundamentally different from machines, mainly because they are “closed with respect to effcient causation.” The proof for this theorem rests on two crucial assumptions. The first is that for a certain class of systems (“mechanisms”) analytic modeling is the inverse of synthetic modeling. The second is that aspects of machines can be modeled using relational models and that these relational models are themselves refined by at least one analytic model. We show that both assumptions are unjustified. We conclude that these results cast serious doubts on the validity of Rosen's proof.
Belanda Hitam: the Indo-African Communities on Java
Authors: van Kessel Ineke
Published: August 2007

Most of the successive groups of African immigrants to the Indonesian archipelago have disappeared without trace, or at least without leaving recognisable descendants. The Belanda Hitam or Black Dutchmen are the one exception. Belanda Hitam was the Malay name given to some 3,000 soldiers from West Africa who were recruited for the Dutch colonial army between 1831 and 1872, and to the Indo-African descendants of these African soldiers and their Indonesian wives. From the 1830s until Indonesian independence, the African soldiers, their Indonesian wives and their Indo-African off spring formed small but vibrant communities in the garrison towns of Java, mainly in Batavia, Semarang, Salatiga, Solo and Purworejo. This article, largely based on interviews with descendants now living in the Netherlands, explores life in these Indo-African communities, with a particular focus on Purworejo.1
Sidis in Mumbai: Negotiating Identities between Mumbai and Gujarat
Authors: Shroff Beheroze
Published: August 2007

In this essay, I discuss issues of identity within the context of social and economic circumstances of the Sidi1 community in Mumbai. I argue that the Sidis who work as caretakers of shrines in Mumbai are accorded dignity and status from the community of devotees who are often from the Muslim, Hindu and Parsi Zoroastrian communities. Those Sidis who are dispersed in different parts of the city and who work as domestics in the homes of middle class Muslim or Hindu families, on the other hand, merge into the nameless toiling masses of the city of Mumbai. Most of these Sidis work in low-income jobs and live in one or two room shanty dwellings. Part of my enquiry also raises the question of home and belonging for the Sidi community. Where do Sidis locate home and how do they construct belonging in India? Finally, I conclude my essay by examining a very different Sidi presence in Mumbai, that of the descendants of the royal family of the Sidis of Janjira (an island off the coast of Mumbai) who live in the upper middle class area of Mumbai. I discuss how the descendants of the Sidis of Janjira construct identity in terms of class and privilege.
Transatlantic Dialogue: Roger Bastide and the African American Religions
Authors: Capone Stefania
Published: August 2007

This article considers the role played by Roger Bastide in the development of studies of religions and cultures of African origin in Brazil. Bastide's interpretation of syncretism in religious phenomena has left its imprint on Afro-Brazilian studies. I will analyze two paradigms used by this author in his treatment of the logic of syncretism: the 'principle of compartmentalization' and the opposition between material acculturation and formal acculturation. I will show how, within the Afro-American religious universe, one finds two types of differentially defined syncretism: an Afro-African syncretism, prior to slavery, that lays the foundation for the idea of a basic unity of African culture, and an Afro-western syncretism that one must fight today. The notion of 'ritual panafricanism', which accounts for this 'positive' syncretism between religions with a similar ancestry, revives the Afro-Brazilian vision of 'unity in diversity' that is largely inspired by Bastidian theories.
Peasants, Migrants and the Discovery of African Traditions: Ritual and Social Change In Lowland Haiti
Authors: Richman Karen
Published: August 2007

Observers of Haitian popular religion have defined Vodou as the authentic African religion of Haitian peasants. In fact, Vodou's congregational forms and practices evolved in and around Port-au-Prince during the twentieth century as the local peasantry was being coerced into wage labor. This paper deals with the incorporation of these ritual innovations in a particular hamlet in Léogane. The agents of ritual diffusion appear to have been not only redundant peasants and neophyte proletarians circulating between the capital city and the nearby plain, but also ethnologists who moved between privileged sites of the Vodou laboratory. The scientific valorization of the heroic slave religion was a centerpiece of the Haitian ethnologists' counter-narrative to European cultural hegemony and North American colonialism. Though their approach to Vodou was part of counter-hegemonic, nationalist discourse, it nonetheless recapitulated a modern view of tradition-bound primitives.
Free to Be a Slave: Slavery as Metaphor in the Afro-Atlantic Religions
Authors: Matory J. Lorand
Published: August 2007

Scholars tend to regard enslavement as a form of disability inflicted upon the enslaved. This paper confronts the irony that not all black Atlantic peoples and religions conceive of slavery as an equally deficient condition or as the opposite of freedom and other rights that are due to respected human beings. Indeed, the religions of enslaved Afro-Latin Americans and their descendants—including Brazilian Candomblé, Cuban and Cuban-diaspora Ocha (or Santería) and Haitian Vodou—are far more ambivalent about slavery than most scholars and most Black North Americans might expect. In these religions, the slave is often understood to be the most effective spiritual actor, either as the most empowering servant of the supplicant's goals or as the most effective model for supplicants' own action upon the world. These ironies are employed to illuminate the unofficial realities of both the Abrahamic faiths and the North American practices of 'freedom'.
The Decline of Uroscopy in Early Modern Learned Medicine (1500-1650)
Authors: Stolberg Michael
Published: August 2007

From the early sixteenth century, uroscopy lost much of the great appeal it had possessed among medieval physicians. Once valued as an outstanding diagnostic tool which ensured authority and fame, it became an object of massive criticism if not derision. As this paper shows, growing awareness of theoretical inconsistencies, the new medical empiricism and humanistic opposition against Arabic and medieval predecessors can explain this drastic revaluation only in part. Uroscopy, it is argued here, came to be perceived above all as a threat to the physicians' professional authority. Faced with persistent demands that they diagnose diseases primarily if not exclusively from urine, they were left with an awkward choice. They risked making fools of themselves by blatant misdiagnosis, but if they rejected the patients' demands people would deem them incapable of a task which many of their less educated competitors were perfectly happy to perform. In the end, in spite of the physicians' massive campaign against it, uroscopy remained very much alive. On the highly competitive early modern medical market patient power had once more prevailed.
Neonatal Abstinence Syndrome and Cerebral Infarction Following Maternal Codeine Use During Pregnancy
Authors: Reynolds Eric W. , Riel-Romero Rosario Maria S. , Bada Henrietta S.
Published: August 2007

Neonatal withdrawal from maternal drugs and medications is common in some NICUs. Codeine-containing cough preparations given to pregnant mothers have been identified as a cause of neonatal abstinence syndrome. However, many women do not consider prescription cough syrups when asked about drug use. Maternal medication or illicit drug use has been identified as a cause of perinatal arterial stroke. Since codeine is an opiate with similar pharmacodynamic effects to morphine, it is reasonable to investigate if maternal codeine use has effects on the fetus that are similar to other opiates. The authors present 2 cases of newborn infants with perinatal arterial stroke that may have been associated with in utero exposure to codeine. Physicians should ask about maternal medication use, including codeine-containing cough preparations, when evaluating newborn infants with evidence of cerebral infarction.
Ethnic Differences in Perceptual Testing
Authors: Adevai Greta , Silverman Albert J. , McGough W. Edward
Published: August 2007

Two large random samples of male college freshmen were measured on a ten-test visual-tactile perceptual battery and on the College Boards Scholastic Aptitude Test. Ethnic group membership was found to be related to performance on the perceptual tests but not to scholastic aptitude. Implications of the findings and tentative directions for future research are discussed.
Mental Health Patients in a Barrio Health Center
Authors: Heiman Elliott M. , Kahn Martin W.
Published: August 2007

U TILIZATION by Mexican Americans of Mental Facilities of a Barrio area neighborhood health center, and demographic and symptom characteristicts of this population were investigated. The findings suggest that contrary to other studies this program was able to reach a high risk Mexican American population frequently missed by mental health programs. The barrio location, the relationship to a neighborhood health clinic and a large proportion of Spanish speaking and local personnel, seemed to be factors in this result. The patients tended to be young adult women with marital problems, somatic complaints and depressive symptoms.

Significant under-utilization of mental health facilities by Mexican Americans has been reported in several studies (12,7). Since Mexican Americans are predo minantly in the lower socio-economic groups which have a greater incidence of psychopathology than higher socio-econimic groups (5, 8, 17), the explanation would not seem to be that Mexican Americans have fewer emotional problems. Rather, it would appear that Mexican Americans do not utilize available services and have psychological problems that go untreated. While there may be several other explanations for this under-utilization, this study attempted to demonstrate that in an appropriate helping facility, such as a mental health program integrated into a Barrio neighborhood health center, this under-utilization would not occur. In addition, the study examined the demographic and symptom characteristics of the Mexican American mental health population of the center, and compared these dimensions with those of outpatient mental health clinics dealing with more general populations. While there was no compelling reason to consider that the Mexican American population would be significantly different from other groups of similar socio-economic status, this comparison has not been as yet adequately assessed.

Data for comparison of the characteristics of our sample with persons receiving outpatient mental health services have been reported in several studies. Bahn, Chandler, and Eisenberg (1) have summarized characteristics for all outpatients in the State of Maryland; and, in a somewhat later paper, Rosen, Bahn and Kramer (14) presented the same data for the entire United States. Thus, national and state level characteristics of individuals receiving outpatient mental health services are available. In addition, characteristics of populations of certain local clinics have been compared with other geographically diverse clinics. In this connection, McKnight, Reznikoff, and Mulligan (10) compared demographic characteristics of patients in their outpatient clinic to that of the entire area of Hartford, Con necticut. Ginott and Lebow (4) have compared characteristics of a local northern region outpatient clinic with those of a local southern region clinic.