bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification and Characterization of an
Acinetobacter baumannii
Biofilm-Associated Protein
Authors: Loehfelm Thomas W. , Luke Nicole R. , Campagnari Anthony A.
Published: November 2007

We have identified a homologue to the staphylococcal biofilm-associated protein (Bap) in a bloodstream isolate of
Acinetobacter baumannii
. The fully sequenced open reading frame is 25,863 bp and encodes a protein with a predicted molecular mass of 854 kDa. Analysis of the nucleotide sequence reveals a repetitive structure consistent with bacterial cell surface adhesins. Bap-specific monoclonal antibody (MAb) 6E3 was generated to an epitope conserved among 41% of
A. baumannii
strains isolated during a recent outbreak in the U.S. military health care system. Flow cytometry confirms that the MAb 6E3 epitope is surface exposed. Random transposon mutagenesis was used to generate
A. baumannii bap1302
::EZ-Tn
5
, a mutant negative for surface reactivity to MAb 6E3 in which the transposon disrupts the coding sequence of
bap
. Time course confocal laser scanning microscopy and three-dimensional image analysis of actively growing biofilms demonstrates that this mutant is unable to sustain biofilm thickness and volume, suggesting a role for Bap in supporting the development of the mature biofilm structure. This is the first identification of a specific cell surface protein directly involved in biofilm formation by
A. baumannii
and suggests that Bap is involved in intercellular adhesion within the mature biofilm.
SmdAB, a Heterodimeric ABC-Type Multidrug Efflux Pump, in
Serratia marcescens
Authors: Matsuo Taira , Chen Jing , Minato Yusuke , Ogawa Wakano , Mizushima Tohru , Kuroda Teruo , Tsuchiya Tomofusa
Published: November 2007

We cloned genes, designated
smdAB
, that encode a multidrug efflux pump from the chromosomal DNA of clinically isolated
Serratia marcescens
NUSM8906. For cells of the drug-hypersensitive strain
Escherichia coli
KAM32 harboring a recombinant plasmid carrying
smdAB
, structurally unrelated antimicrobial agents such as norfloxacin, tetracycline, 4′,6-diamidino-2-phenylindole (DAPI), and Hoechst 33342 showed elevated MICs. The deduced amino acid sequences of both SmdA and SmdB exhibited similarities to the sequences of ATP-binding cassette (ABC)-type multidrug efflux pumps. The efflux of DAPI and Hoechst 33342 from
E. coli
cells expressing SmdAB was observed, and the efflux activities were inhibited by sodium
o
-vanadate, which is a well-known ATPase inhibitor. The introduction of
smdA
or
smdB
alone into
E. coli
KAM32 did not elevate the MIC of DAPI; thus, both SmdA and SmdB were required for function. These results indicate that SmdAB is probably a heterodimeric multidrug efflux pump of the ABC family in
S. marcescens
.
Child wellbeing and income inequality in rich societies: ecological cross sectional study
Authors: Pickett Kate E , Wilkinson Richard G
Published: November 2007

Objectives
To examine associations between child wellbeing and material living standards (average income), the scale of differentiation in social status (income inequality), and social exclusion (children in relative poverty) in rich developed societies.

Design
Ecological, cross sectional studies.

Setting
Cross national comparisons of 23 rich countries; cross state comparisons within the United States.

Population
Children and young people.

Main outcome measures
The Unicef index of child wellbeing and its components for rich countries; eight comparable measures for the US states and District of Columbia (teenage births, juvenile homicides, infant mortality, low birth weight, educational performance, dropping out of high school, overweight, mental health problems).

Results
The overall index of child wellbeing was negatively correlated with income inequality (
r
=−0.64, P=0.001) and percentage of children in relative poverty (
r
=−0.67, P=0.001) but not with average income (
r
=0.15, P=0.50). Many more indicators of child wellbeing were associated with income inequality or children in relative poverty, or both, than with average incomes. Among the US states and District of Columbia all indicators were significantly worse in more unequal states. Only teenage birth rates and the proportion of children dropping out of high school were lower in richer states.

Conclusions
Improvements in child wellbeing in rich societies may depend more on reductions in inequality than on further economic growth.
Problems in the current diagnostic standards of clinical N1 non-small cell lung cancer
Authors: Hishida T , Yoshida J , Nishimura M , Nishiwaki Y , Nagai K
Published: November 2007

Background:

Although clinical N1 (cN1) non-small cell lung cancer (NSCLC) is considered to be locoregional, the postoperative outcome is disappointing, with a 5 year survival of less than 50%. One possible reason may be that cN1disease diagnosed by current standard imaging modalities often contains unexpected N2 disease. This study was conducted to evaluate the surgical and pathological results of patients with cN1 NSCLC.

Methods:

Among 1782 patients with NSCLC who underwent intended curative resection from 1993 to 2003, 143 patients were identified as having cN1 disease and were enrolled in this study. The clinicopathological records and CT films of each patient were retrospectively reviewed to identify predictors for pN2–3 disease.

Results:

The pathological nodal status was pN0 in 23% (n = 33), pN1 in 47% (n = 67) and pN2–3 in 30% (n = 43) of patients. Patients with pN2–3 showed a significantly worse 5 year survival rate of 38% compared with patients with pN0 (68%) and pN1 (60%) (p = 0.017 and 0.007, respectively). Multivariate analysis showed that adenocarcinoma histology was a significant predictor for pN2–3 disease (OR 3.312, 95% CI 1.439 to 7.784; p = 0.005). The presence of N1 node separate from the main tumour on CT scans tended to predict pN2–3 disease although this did not reach statistical significance (OR 2.103, 95% CI 0.955 to 4.693; p = 0.066). Pathological N2–3 disease was found in 53% of patients with adenocarcinoma with a separate N1 pattern and in only 12% of patients with non-adenocarcinoma with a continuous N1 pattern.

Conclusions:

The diagnosis of N1 status by contrast enhanced CT scans is unsatisfactory with a high rate of unexpected pN2 disease. To avoid infertile lung resection, patients with CT diagnosed N1 adenocarcinoma, especially with a separate N1 pattern on CT, should be considered for additional invasive node biopsy modalities, including mediastinoscopy.
Upper crustal response to Mesozoic tectonism in western Liaoning, North China, and implications for lithospheric delamination
Authors: Cope T. D. , Graham S. A.
Published: November 2007

A widespread and well-documented episode of Late Jurassic–Early Cretaceous rifting followed multiple events of mid- to late Mesozoic crustal contraction in NE China. This extensional deformation was closely associated with widespread Mesozoic magmatism, thought to be related to lithospheric delamination and destabilization of the previously stable North China craton. Early Cretaceous rift-related sedimentary basins in the western Liaoning region of NE China comprise numerous discrete, largely lacustrine half-graben basins bounded by NW-rooting low-angle normal faults that sole into older thrusts or mid-crustal shear zones. These basins characteristically lack post-rift thermal subsidence and significantly postdate most of the Mesozoic volcanism in the region. Instead, magmatism that has been attributed to lower crustal foundering, and hence lithospheric delamination (perhaps as old as 160 Ma) accompanied continuing crustal thickening in eastern North China. Thus, although widespread magmatism plausibly played a role in thermally weakening the crust prior to extension, there is little upper crustal evidence that wholesale removal of the lithosphere and lower crust occurred during Mesozoic time. The expansive Cenozoic rift basins of Eastern China, which do contain thick post-rift sequences, constitute a more viable response to lithospheric delamination.
Phanerozoic evolution of the Inner Mongolia–Daxinganling orogenic belt in North China: constraints from geochronology of ophiolites and associated formations
Authors: Miao L. , Zhang F. , Fan W.-M. , Liu D.
Published: November 2007

The Inner Mongolia–Daxinganling Orogenic Belt (IMDOB), located between the North China and South Mongolia Blocks, consists of several ENE–WSW- to NE–SW-trending zones including dismembered ophiolite blocks, metamorphic rocks and granitoids. Although numerous studies have been carried out on this belt, its tectonic evolution has been a subject of controversy, chiefly because of the lack of reliable geochronological data. Based on a synthesis of newly published geochronological data and our unpublished data for the IMDOB, we define two oceanic basins: Ondor Sum and Hegenshan. The former, probably the main one, was initiated during the Ordovician (>467 Ma) period, whereas the latter, representing a back-arc basin, opened on a pre-Permian basement at, or earlier than, Early Permian times (
c
. 295 Ma). These two oceanic basins were separated by a magmatic arc (Sunid–Baolidao), and were probably closed simultaneously when the final orogenesis of the IMDOB occurred during the Triassic period (240–220 Ma). Importantly, the Triassic timing of the final orogenesis of the IMDOB due north of the North China Craton is essentially coeval with that of the Qinling–Dabie–Su–Lu orogenic belt on the southern margin of the North China Craton. It is inferred that this two-sided subduction–collision scenario in the Triassic may have contributed to the Mesozoic lithospheric thinning event of the North China Craton, although the details are unclear.
Late Mesozoic tectonic transition of the eastern North China Craton: evidence from basin-fill records
Authors: Li Z. , Li Y. , Zheng J.-P. , Han D.
Published: November 2007

To better understand Mesozoic tectonic transition processes in Eastern China, this paper offers a comparison of Mesozoic basin-fill records around the eastern North China Craton. These Mesozoic basins have similar evolutionary features: inception since the Early Jurassic; basin-fills recording a tectonic evolution from compression and lithospheric thickening before Late Jurassic and/or Early Cretaceous time to intracontinental stretching and lithospheric thinning from Early Cretaceous time; tectonic transition during the late Jurassic with a time lag in shallow crust relative to deep lithosphere. However, basin-fill records reflect two distinct basin systems occurring in the southern and northern margins of the eastern North China Craton. First, varied volcanic rocks including mafic, intermediate–mafic and intermediate–felsic assemblages occur in the Yanshan–Liaoxi basins on the northern margin of the eastern North China Craton from the Early Jurassic to Cretaceous; in contrast, limited calc-alkaline volcanic rocks filled the Hefei basin system on the southern margin of the eastern North China Craton during the Late Jurassic–Early Cretaceous. Second, late Mesozoic lithospheric thinning began at about 163 Ma and 149 Ma in the northern and southern margins, respectively, culminating in basin-scale extensional events at about 145 Ma and 132 Ma, respectively. Third, coarse clastic sediments developed in the northern and southern basins during the tectonic transition phase reflect fluvial and alluvial systems, respectively, indicating greater topographic relief in the southern area than in the northern area. Fourth, Mesozoic depocentre migration was complicated in the Yanshan–Liaoxi basin but should a south to north trend in the Hefei basin system. Mesozoic basin-fill depositional and volcanic records in the southern margin of the eastern North China Craton were dominantly controlled by early Mesozoic deep subduction of the Yangtze block and subsequent post-orogenic extension of the Dabie Mountains. On the other hand, basin-fill evolution along the northern margin of the North China Craton was principally controlled by intensive crust–mantle and/or asthenosphere–lithosphere interactions, with regional transition from contractile to extensional strain during Mesozoic time. This study suggests that the late Mesozoic tectonic transition was first induced by crust–mantle interactions in the northern North China Craton and then it extended southwards. Late Mesozoic lithospheric thinning and subsequent tectonic transition are a linked systematic geodynamic process that has no direct relation to the Triassic plate convergence events around the North China Craton.
East Marginal Fault of the Yellow Sea: a part of the conjunction zone between Sino‐Korea and Yangtze Blocks?
Authors: Hao T.-Y. , Xu Y. , Suh M. , Xu Y. , Liu J.-H. , Zhang L.-L. , Dai M.-G.
Published: November 2007

The conclusions of most previous studies on the eastward extension of the collision zone between the Sino-Korean and Yangtze Blocks can generally be divided into two categories: (1) the collision zone is connected to the Imjingang belt and crosses the Korean Peninsula; (2) the eastward extension of the collision zone does not enter the Korean Peninsula, nor is connected to the Imjingang belt. Recent geophysical studies on gravity and velocity tomography in the Yellow Sea and adjacent regions, respectively, have provided geophysical evidence for a nearly north–south-trading dextral strike-slip fault in the eastern margin of the Yellow Sea, which we have named the East Marginal Fault of the Yellow Sea (EMFYS). The geophysical evidence indicates that the EMFYS extends to great depth. It dips westward, and within 100 km depth the dip angle is very steep. The geophysical characteristics on its two sides show that they belong to different tectonic units. This fault is connected to the Wulian–Qingdao Fault in the north, and to the South Marginal Fault of Jeju Island (SMFJI) in the south (the SMFJI is a part of the collision zone). Therefore the EMFYS is considered as a part of the junction zone between the Sino-Korea and Yangtze Blocks, with the Korean Peninsula being part of the Sino-Korea Block. In the Late Triassic, it is inferred that dextral strike-slip movement took place on the EMFYS, and in the same geological period sinistral strike-slip took place on the Tan-Lu Fault Zone. Under north–south tectonic stress the Yangtze Block was translated northward and inserted into the Sino-Korea Block. Therefore the junction zone between the two blocks formed a gigantic Z-shaped tectonic belt. According to the gravity data and seismic tomography it is also inferred in this paper that the junction zone between the Yangtze and Cathaysia Blocks extends from the Jiangshao Fault eastward to the southern edge of the Hida Block, Japan.
Crustal P-wave velocity distributions and metallotectonics around the North China Craton
Authors: Chang X. , Liu Y. , Zhai M.-G. , Wang Y.
Published: November 2007

We have collected seismic data, performed high-resolution seismic tomography in the North China Craton and analysed the relationships between crustal seismic velocity distributions and regional tectonics and metallogenesis. In the upper and middle crust velocity anomalies are distributed along east–west- and NNE–SSW-trending structures. Most belts of Cenozoic mineral deposits including gold in the North China Craton coincide with high-velocity anomalies, and the North China basin coincides with a low-velocity zone. Compared with the upper crust, the low-velocity anomalies in the lower crust are diffuse and extensive, which suggests that high-temperature material has upwelled from the mantle. High-temperature material in the lower crust provided buoyant, hot, mineralizing fluids that uplifted and formed the Cretaceous mineral deposits in the upper crust.
Lithospheric thinning in eastern Asia; constraints, evolution, and tests of models
Authors: Kusky T. M. , Windley B. F. , Zhai M.-G.
Published: November 2007

The North China Craton (NCC) is the only place currently recognized where an Archaean craton developed a continental root in the Archaean, and subsequently lost half of that root in younger tectonism. In this volume, various authors have advanced different models of root loss, and provided geological, geophysical and geochemical data that help constrain the geometry and timing of root loss. Understanding why and how roots are lost may help us understand how often this process may have occurred in the geological past, and how much lithospheric material has been recycled to the convecting mantle through this mechanism, potentially drastically changing our current understanding of crustal growth rates and processes. With current data, there are several equally plausible possibilities that require further data collection for testing. There are several possible tectonic triggers that may have caused half the root to be lost, acting either separately or together. These include collisional, extensional, plume-related, fluid-weakening, spontaneous, and more complex hybrid mechanisms. We also do not know why only the eastern half of the root was lost, and not the root from beneath the whole craton. One tantalizing idea is that the root grew independently, by tectonic underplating of subducted buoyant oceanic lithosphere, beneath the previously separate eastern and western halves of the craton by 2.5 Ga, with modification at 1.8 Ga. If so, perhaps only the eastern half of the root was lost in younger tectonism because there was some physical or geometric difference between the two halves. Alternatively, collisional or subduction-related tectonic processes acting only on the Eastern Block may have caused the disruption of the tectosphere there in the Mesozoic. The timing of and mechanism for loss of the root is not uniquely resolvable with current data, but a solution to the problem is in reach. Possible triggering mechanisms include, but are not limited to, collision of the South China (Yangtze) and North China Cratons in the Triassic, the India–Asia collision, closure of the Solonker and Mongol–Okhotsk oceans, Mesozoic subduction of the Pacific plate beneath Eastern China, impingement of mantle plumes, mantle hydration from long-term subduction, and several rifting events. In this concluding review, we link studies of crustal tectonics with investigations aimed at determining the nature and timing of the formation and loss of the root, to better understand mechanisms of continental root formation, evolution and recycling–removal.
Temporal and spatial distribution of Mesozoic mafic magmatism in the North China Craton and implications for secular lithospheric evolution
Authors: Zhang H.-F.
Published: November 2007

Mesozoic mafic magmatism in the North China Craton shows a clear temporal and spatial distribution. Mesozoic mafic volcanism occurred dominantly in the northern and southern margins of the craton, with episodic eruptions from Early Jurassic to Late Cretaceous time. In contrast, Mesozoic mafic magmatism, which produced gabbroic to dioritic intrusive complexes, occurred in the centre of the craton in areas such as the Taihang Mountains and the Luzhong region, and all the complexes were intruded at almost the same time in the Early Cretaceous. This temporal and spatial distribution of Mesozoic mafic magmatism shows a strong heterogeneity of the Late Mesozoic lithospheric mantle beneath the North China Craton and a secular evolution of the lithospheric mantle beneath it. The lithospheric mantle beneath the Luzhong region is slightly isotopically enriched; that beneath the Taihang Mountains has an EM1 character in Sr and Nd isotopic features (
87
Sr/
86
Sr)
i
=0.7050–0.7066; ε
Nd(t)
=−17 to −10); and it possesses EM2-like characteristics (
87
Sr/
86
Sr)
i
up to 0.7114) beneath the Luxi–Jiaodong region. The general enrichment suggests that the Mesozoic lithospheric mantle was distinctive compared with Palaeozoic and Cenozoic counterparts. The secular evolution of this variably enriched Mesozoic lithospheric mantle requires a considerable modification, transformation and reconstruction of the lithospheric mantle beneath the craton in Late Mesozoic time. The elemental and isotopic compositions and the coherence of the lithospheric changes with the formation of circum-craton orogenic mobile belts indicate that these rapid lithospheric changes and corresponding lithospheric thinning were tectonically related to the multiple subduction and subsequent collisions of circum-craton blocks. Dehydration melting of subducted oceanic and continental crustal materials produced silicic melts that migrated up and reacted with lithospheric peridotites to generate more fertile lithospheric mantle (‘wet’ low-Mg peridotites plus pyroxenite veins). This is demonstrated by the fact that beneath the southern and northern margins the mantle was strongly modified, but beneath the central craton the effects were less marked. Compositional mapping of olivine from mantle peridotitic xenoliths and xenocrysts entrained in Mesozoic and Cenozoic basalts and mafic rocks throughout the craton suggests a similar framework. The North China Craton provides convincing evidence that the nature of the refractory lithospheric mantle was considerably changed in chemical composition through time, and that the lithospheric destruction was triggered by multiple circum-craton subductions and collisions.
Geochemistry of Mesozoic mafic volcanic rocks from the Yanshan belt in the northern margin of the North China Block: relations with post-collisional lithospheric extension
Authors: Guo F. , Fan W.-M. , Li X.-Y. , Li C.-W.
Published: November 2007

Major element, trace element and Sr–Nd isotope data for three suites of mafic volcanic rocks that erupted at
c
. 180 Ma (Group 1),
c
. 163–140 Ma (Group 2) and 136–110 Ma (Group 3) in the Yanshan belt in the northern margin of the North China Block (NCB) are presented in this paper. All the rocks show significant enrichment in large ion lithophile elements and light REE (LREE) but depletion in Nb–Ta and Th–U, and moderately radiogenic Sr (
87
Sr/
86
Sr(i)= 0.7052–0.7068) and unradiogenic Nd (ε
Nd
(
t
)=−15.1 to −7.2) isotopic compositions. Sr–Nd isotopic modelling suggests an insignificant role of crustal contamination or assimilation fractional crystallization, and the geochemical variations in these rocks were mainly attributed to source heterogeneity and variable degrees of ferromagnesian, plagioclase and accessory mineral fractionation. The low Th/La (0.039-0.10) points to recycling of low-Th/La (e.g. Th/La <0.2) ancient crustal materials into the source region, probably related to the palaeo-Asian Ocean subduction. Compared with the late Mesozoic mafic rocks from the NCB interior, the Yanshan belt mafic lavas generally have higher Al
2
O
3
, TiO
2
, P
2
O
5
, LREE, high field strength elements, Sr and
87
Sr/
86
Sr(i) but lower MgO and compatible elements. Major element extrapolation (MgO=8% normalization) reveals that the Yanshan belt mafic volcanic rocks have higher Ti
8
and Fe
8
, and lower Si
8
than those from the NCB interior, suggesting that they were probably derived from a relatively fertile mantle source, different from the Mesozoic chemically refractory lithospheric mantle beneath the NCB interior. Combining the geochemical features of the mafic rocks with Mesozoic deformation events in the northern NCB, we suggest that the three stages of mafic volcanism were caused by episodic lithospheric extension. The Group 1 rocks, which occur locally along major faults, were generated during a post-compressional extension related to the collision between the NCB and Mongolian Block; the Group 2 rocks formed as a result of post-collisional lithospheric extension related to the collision between the North China–Mongolian Block and the Siberian plate; and the Group 3 rocks were extruded in an extensional regime in response to lateral escape related to surrounding plate interactions.
Origin of the Mesozoic magmatism in the North China Craton: constraints from petrological and geochemical data
Authors: Chen B. , Zhai M.-G. , Tian W.
Published: November 2007

Voluminous plutonic and volcanic rocks were emplaced in the eastern part of the North China Craton (NCC) in the Mesozoic. The Mesozoic igneous rocks include a variety of rock types ranging from monzogabbroic, through monzonitic to monzogranitic, and locally to syenitic. Monzonitic rocks are dominant, and frequently contain mafic enclaves (dioritic in composition). The principal geochemical signatures of these Mesozoic rocks include high-K calc-alkaline to shoshonitic affinity, high Sr–Ba abundances and high Sr/Y, La/Yb, and highly enriched Sr–Nd isotopic compositions with ε
Nd
(
t
) ranging from −8 to −20 and
I
Sr
from 0.7053 to 0.710. Zircon sensitive high-resolution ion microprobe dating reveals that these Mesozoic rocks formed between 180 Ma and 120 Ma, but are predominantly confined to a narrow range of 135–127 Ma. The sudden surge of Mesozoic magmatism was genetically linked to the upwelling of asthenosphere in a back-arc extensional regime that was caused by subduction of the palaeo-pacific plate beneath the eastern NCC. Upwelling of hot asthenospheric mantle material triggered partial melting of enriched subcontinental lithosperic mantle, generating voluminous mafic magmas. The mafic magmas underplated in the lower crust and sparked melting of the latter, producting granitic melts. We suggest that the Mesozoic rocks in the NCC probably originated from mixing between the coeval mafic and granitic melts, followed by fractionation of ferromagnesian phases and subordinate plagioclase, rather than from melting of mafic lower crust as previously suggested by many others.
Renal mitochondrial impairment is attenuated by AT1blockade in experimental Type I diabetes
Authors: de Cavanagh Elena M. V. , Ferder León , Toblli Jorge E. , Piotrkowski Bárbara , Stella Inés , Fraga Cesar G. , Inserra Felipe
Published: November 2007

To investigate whether ANG II type 1 (AT1) receptor blockade could protect kidney mitochondria in streptozotocin-induced Type 1 diabetes, we treated 8-wk-old male Sprague-Dawley rats with a single streptozotocin injection (65 mg/kg ip; STZ group), streptozotocin and drinking water containing either losartan (30 mg·kg−1·day−1; STZ+Los group) or amlodipine (3 mg·kg−1·day−1; STZ+Amlo group), or saline (intraperitoneally) and pure water (control group). Four-month-long losartan or amlodipine treatments started 30 days before streptozotocin injection to improve the antioxidant defenses. The number of renal lesions, plasma glucose and lipid levels, and proteinuria were higher and creatinine clearance was lower in STZ and STZ+Amlo compared with STZ+Los and control groups. Glycemia was higher in STZ+Los compared with control. Blood pressure, basal mitochondrial membrane potential and mitochondrial pyruvate content, and renal oxidized glutathione levels were higher and NADH/cytochrome c oxidoreductase activity was lower in STZ compared with the other groups. In STZ and STZ+Amlo groups, mitochondrial H2O2production rate was higher and uncoupling protein-2 content, cytochrome c oxidase activity, and renal glutathione level were lower than in STZ+Los and control groups. Mitochondrial nitric oxide synthase activity was higher in STZ+Amlo compared with the other groups. Mitochondrial pyruvate content and H2O2production rate negatively contributed to electron transfer capacity and positively contributed to renal lesions. Uncoupling protein-2 content negatively contributed to mitochondrial H2O2production rate and renal lesions. Renal glutathione reduction potential positively contributed to mitochondria electron transfer capacity. In conclusion, AT1blockade protects kidney mitochondria and kidney structure in streptozotocin-induced diabetes independently of blood pressure and glycemia.
Aortic wave intensity analysis of ventricular-vascular interaction during incremental dobutamine infusion in adult sheep
Authors: Penny Daniel J. , Mynard Jonathan P. , Smolich Joseph J.
Published: November 2007

This study undertook a detailed examination of the ventricular-vascular interaction of the predominant β-adrenergic agonist dobutamine using wave intensity analysis. Eight anesthetized open-chest ewes were instrumented with an aortic micromanometer to measure central aortic blood pressure (P) and an ultrasonic flow probe to obtain ascending aortic blood velocity ( U). Hemodynamics were recorded during incremental dobutamine infusion (0.5, 1, 2.5, 5, 7.5, and 10 μg·kg−1·min−1). Wave intensity (d IW) was calculated as the product of the rates of change of P and U with customized software using ensemble-averaged signals. Forward and backward components of d IW, P, and U were determined after calculation of wave speed. As well as the typical initial forward compression wave (FCW), midsystolic backward compression wave (BCW), and late-systolic forward expansion wave (FEWes), two minor and previously unheralded waves were also detectable in the wave intensity profile at baseline. The first was an early systolic backward expansion wave (BEW), which reduced P but increased peak U. The second was a mid-systolic forward expansion wave (FEWms), which reduced P and U. During dobutamine infusion FCW d IW increased 18-fold ( P < 0.001), but BCW d IW rose 12-fold ( P < 0.001) while FEWes d IW fell by 70% ( P < 0.001). However, the latter changes were accompanied by a 44-fold increase in BEW d IW ( P = 0.005) that augmented the initial aortic forward flow and a >100-fold rise in FEWms d IW ( P < 0.001) that produced earlier and enhanced aortic blood deceleration. These findings provide new insights into the ventricular-vascular interaction of dobutamine.
Cardiac alternans in embryonic mouse ventricles
Authors: de Diego Carlos , Chen Fuhua , Xie Lai-Hua , Dave Amish S. , Thu Mya , Rongey Christine , Weiss James N. , Valderrábano Miguel
Published: November 2007

T-wave alternans, an important arrhythmogenic factor, has recently been described in human fetuses. Here we sought to determine whether alternans can be induced in the embryonic mouse hearts, despite its underdeveloped sarcoplasmic reticulum (SR) and, if so, to analyze the response to pharmacological and autonomic interventions. Immunohistochemistry confirmed minimal sarcoplasmic-endoplasmic reticulum Ca-ATPase 2a expression in embryonic mouse hearts at embryonic day (E) 10.5 to E12.5, compared with neonatal or adult mouse hearts. We optically mapped voltage and/or intracellular Ca (Cai) in 99 embryonic mouse hearts (dual mapping in 64 hearts) at these ages. Under control conditions, ventricular action potential duration (APD) and Cai transient alternans occurred during rapid pacing at an average cycle length of 212 ± 34 ms in 57% ( n = 15/26) of E10.5-E12.5 hearts. Maximum APD restitution slope was steeper in hearts developing alternans than those that did not (2.2 ± 0.6 vs. 0.8 ± 0.4; P < 0.001). Disabling SR Cai cycling with thapsigargin plus ryanodine did not significantly reduce alternans incidence (44%, n = 8/18, P = 0.5), whereas isoproterenol ( n = 14) increased the incidence to 100% ( P < 0.05), coincident with steepening APD restitution slope. Verapamil abolished Cai transients ( n = 9). Thapsigargin plus ryanodine had no major effects on Cai-transient amplitude or its half time of recovery in E10.5 hearts, but significantly depressed Cai-transient amplitude (by 47 ± 8%) and prolonged its half time of recovery (by 18 ± 3%) in E11.5 and older hearts. Embryonic mouse ventricles can develop cardiac alternans, which generally is well correlated with APD restitution slope and does not depend on fully functional SR Cai cycling.
The Angolan Churches from the Bicesse to the Luena Peace Agreements (1991-2002): The Building of a Peace Agenda and the Road to Ecumenical Dialogue
Authors: Comerford Michael
Published: November 2007

This article examines how the major Angolan churches engaged with the search for peace from 1991 to 2002, the crucial period from the Bicesse Accords to the Luena Memorandum following the death of Jonas Savimbi, which ended the years of cyclical military conflict and broken peace agreements. It sets out how the churches analysed the causes of the conflict between the MPLA-led government and the UNITA rebel movement, as well as what they believed was required to bring about peace. This analysis is unique in Angola as no other national civic voice consistently engaged with the peace agenda over this period. The article also examines ecumenical initiatives to restore peace through the formation of COIEPA, the inter-ecclesial peace committee, following the return to war in 1998, initiatives that were strongly resisted by the government as it pursued its military strategy of bringing peace to Angola by fighting a final and decisive war.
'Broken Calabashes and Covenants of Fruitfulness': Cursing Barrenness in Contemporary African Christianity
Authors: Asamoah-Gyadu J. Kwabena
Published: November 2007

Childlessness is an issue of deep religious concern in Africa. Men, women and couples with problems of sexuality and childlessness make use not only of the resources of traditional African religions but also of the many Pentecostal/charismatic churches and movements that have burgeoned throughout sub-Saharan Africa in the last three decades. Initially this was the domain of the older African independent churches, as far as the Christian response to childlessness is concerned; the new Pentecostals have taken on the challenge too. Based on the same biblical and traditional worldviews that events have causes, these churches have mounted ritual contexts that wrestle with the issues of sexuality and childlessness. In pursuing this salvific endeavor, however, the needs of those who may never have children seem to have been neglected by the churches considered here and represented by the Pure Fire Miracle Ministries, a Ghana/Nigeria charismatic church located in Ghana. is partial approach to 'healing' childlessness has led to one-sided interpretations of what it means to be fruitful and prosperous and deepened the troubles of the childless.
Comparison of Different Regression Analyses for Identifying Risk Factors in Obese and Nonobese Patients With Coronary Artery Disease
Authors: Yologlu Saim , Sezgin Alpay Turan , Sezgin Nurzen , Yetkin Ertan , Olmez Ercument
Published: November 2007

This study was designed to assess conventional and novel risk factors in obese and nonobese patients with coronary artery disease (CAD) by using multivariate forward and univariate logistic regression analysis and to find the best model of analysis for identifying these risk factors. The study group consisted of 398 patients who consecutively underwent coronary angiography for the investigation of chest pain, except overweight patients. In univariate logistic regression analysis, high C-reactive protein and cigarette smoking were found to be the strongest variables in obese and nonobese patients with CAD, respectively. In multivariate forward logistic regression analysis, some risk factors were not found as predictors of CAD. Multivariate forward logistic regression analysis with the advantage of a high predictable ratio may be more useful for the analysis of risk factors in patients with CAD.
The Thicker the Skin Fold, the Less Hematoma Development: A Novel Parameter Other Than Body Mass Index Associated With Transradial Vascular Complication
Authors: Li Ai-Hsien , Yeih Dong-Feng , Chen Kuo-Ching , Chu Shu-Hsun , Weng Ching-Sung
Published: November 2007

It was reported recently that body mass index (BMI) is a prognostic factor of vascular complications after radial puncture, and that extremely thin patients are at higher risk than obese subjects. However, the underlining mechanism of this phenomenon has rarely been studied. Therefore, we conducted a survey measuring a novel parameter, the skin fold thickness, and other potential risk factors in our patients developing postprocedure hematoma. In 1176 consecutive patients undergoing percutaneous radial catheterization, 18 (1.53%) developed hematoma afterward. When a patient with hematoma had been identified, the next patient having no hematoma after radial puncture was enrolled into the control group, which thus turned out to have 18 patients. In addition, we also compared the BMI, skin fold thickness, and other potential risk factors, including heparin dosage and antiplatelet medication, between these 2 groups. We found hematoma patients to be older (69.5 ± 10.3 years vs 61.50 ± 11.7 years, P = .037), to have more cases of coronary intervention (10/18 vs 4/18, P = .04), to have lower BMI (23.63 ± 4.03 vs 27.25 ± 4.38, P = .014), and to have thinner skin folds of forearm (5.94 ± 4.56 vs 9.27 ± 3.06 mm, P = .015), deltoid area (14.61 ± 9.00 vs 19.73 ± 7.15 mm, P = .042), and waist (21.94 ± 9.90 vs 29.00 ± 8.46 mm, P = .028) than the nonhematoma group. On the contrary, no statistical difference in heparin dosage or other factors was noted between the 2 groups. We conclude that the vascular complication rate after radial catheterization is higher in elderly patients with lower BMI, body weight, or thinner skin folds.
Alterations in Nitric Oxide Synthase Isoforms in Acute Lower Limb Ischemia and Reperfusion
Authors: Tsui Janice C. S. , Baker Daryll M. , Shaw Sidney G. , Dashwood Michael R.
Published: November 2007

Alterations in nitric oxide synthase (NOS) are implicated in ischemia and ischemia-reperfusion injury. Changes in the 3 NOS isoforms in human skeletal muscle subjected to acute ischemia and reperfusion were studied. Muscle biopsies were taken from patients undergoing total knee replacement. Distribution of the specific NOS isoforms within muscle sections was studied using immunohistochemistry. NOS mRNA levels were measured using real-time reverse transcription-polymerase chain reaction and protein levels studied using Western blotting. NOS activity was also assessed using the citrulline assay. All 3 NOS isoforms were found in muscle sections associated with muscle fibers and microvessels. In muscle subjected to acute ischemia and reperfusion, NOS I/neuronal NOS mRNA and protein were elevated during reperfusion. NOS III/endothelial NOS was also upregulated at the protein level during reperfusion. No changes in NOS II/inducible NOS expression or NOS activity occurred. In conclusion, alterations in NOS I and III (neuronal NOS and endothelial NOS) at different levels occurred after acute ischemia and reperfusion in human skeletal muscle; however, this did not result in increased NOS activity. In the development of therapeutic agents based on manipulation of the NO pathway, targeting the appropriate NOS isoenzymes may be important.
Silent Myocardial Ischemia in Middle-Aged Asymptomatic Patients With Type 2 Diabetes in Turkish Population
Authors: Ugur-Altun Betul , Altun Armagan , Guldiken Sibel , Tatli Ersan , Kara Mujdat , Tugrul Armagan
Published: November 2007

The authors investigated silent myocardial ischemia in unselected consecutive middle-aged asymptomatic patients with type 2 diabetes without any evidence of coronary heart disease documented by treadmill exercise test. Ninety asymptomatic patients with type 2 diabetes (48 men; mean age: 49 ±6 years) were included in the study. Mean duration of diabetes in the study group was 4 ±4.2 years (range 1 to 21 years); 38% of the study population, diabetes duration was only 1 year). All patients were subjected to treadmill exercise test with Bruce protocol. A positive test was noted in 4 of 90 (4%) study patients. Two male patients (4%) and 2 (4%) women patients developed exercise-induced ST-segment depression, but none had concomitant chest pain. Diabetics with silent myocardial ischemia were older (55 ±3 years vs 49 ±6 years, p = 0.04) than those without silent myocardial ischemia. Also, diabetics with silent myocardial ischemia had higher fibrinogen level (372 ±51 vs 307 ±71 mg/dL, p = 0.04) than diabetics without silent myocardial ischemia. In treadmill exercise test, diabetics with silent myocardial ischemia had lower total exercise time and peak workload (375 ±30 vs 474 ±115 seconds, p = 0.04; 7.3 ±0.5 vs 8.9 ±1.9, p = 0.04, respectively) than without silent myocardial ischemia. Insulin resistance is associated with a variety of atherosclerosis risk factors. Exercise test findings show increased cardiac sympathetic activity and parasympathetic withdrawal in increased insulin resistance.
Good Collaterals Predict Viable Myocardium
Authors: Kumbasar Deniz , Akyürek Ömer , Dincer Irem , Atmaca Yusuf , Kılıçkap Mustafa , Erol Çetin , Oral Derviş
Published: November 2007

The authors undertook this study to see whether highly developed coronary collaterals at an area shed by a totally occluded coronary artery predicts myocardial viability. Percutaneous coronary intervention (PCI) of a totally occluded coronary artery has been debated since its introduction. It is recommended to search for viable myocardium before opening a totally occluded coronary artery; however, there is no practical yet sensitive method of assessing myocardial viability in the catheterization laboratory. Forty-seven consecutive patients (12 women, 25.5%; 35 men, 74.5%), each with 1 totally occluded coronary artery, were prospectively enrolled to the study. After the diagnostic coronary angiography, all patients underwent dobutamine stress echocardiography to determine viable myocardium at the territory of the totally occluded coronary artery, and the status of angiographic coronary collaterals was assessed. Patients were then divided into 2 groups according to the presence (Group A) or absence (Group B) of viable myocardium by stress echocardiography. Eighteen patients (38.3%) had viable myocardium (Group A) in the area shed by the totally occluded coronary artery and 29 patients (61.7%) had nonviable myocardium (Group B). The incidences of significant coronary collateral circulation to the viable (Group A) and nonviable (Group B) areas were 66.7% (12 patients) and 20.7% (6 patients), respectively (p = 0.002). Logistic regression analysis was used to evaluate the independent factors for viable myocardium, and only significant coronary collateral circulation was found to be an independent factor for the detection of viable myocardium (p = 0.006, OR 16.7, 95% CI 2.25 to 124.4). The sensitivity and specificity of good collateral circulation for the detection of viable myocardium were 75% and 65.7%, respectively. The positive predictive and negative predictive values of the good coronary collateral circulation in detecting viable myocardium were 75% and 79%, respectively. The authors conclude that good coronary collaterals have a high sensitivity and positive predictive value for the prediction of viability as shown by dobutamine echocardiography, and only by assessing the coronary collateral circulation can one decide for percutaneous coronary revascularization, if not for coronary artery bypass surgery.
Intraobserver and Interobserver Agreements of Leg Circumference Measurements by Tape Measure Based on 3 Reference Points
Authors: Tunc Recep , Caglayan-Tunc Aygul , Kisakol Gurcan , Unler Gulhan Kanat , Hidayetoglu Taha , Yazici Hasan
Published: November 2007

The objective of this study was to evaluate the intraobserver and interobserver agreements in tape measurements of the ankle and calf circumference with due emphasis on the 3 main reference points, the patella, the tibial tuberosity, and the medial malleolus. The leg circumference at 2 locations was measured in 66 patients in the mornings of 2 consecutive days by 6 observers. Finally, a blinded couple measured leg circumferences at a line created on calves with a ballpoint pen of 68 outpatients to calculate interobserver agreement for lined regions. Leg circumference measurement was accepted as correct when the difference was less than 0.6 cm in 2 occasions. Intraobserver and interobserver agreements were calculated as the percentage of correct measurements. Chi-square test was used to compare intraobserver and interobserver agreements for each reference point. At the calf region, intraobserver and interobserver agreements based on the tibial tuberosity (88% and 81%) were better than those of the patella (65% and 57%) and the medial malleolus (73% and 65%). On the other hand, at above the ankle region, the agreements (79% and 62%) were also better than those of the patella (60% and 43%) and nearly the same as those of the medial malleolus (86% and 65%). Finally, interobserver agreement of the measurements at the created line with ballpoint pen (96%) was better when compared to those of the tibial tuberosity (81%), the patella (57%), and medial malleolus (65%) (p = 0.005, p < 0.001, and p < 0.001, respectively). The results of this study suggest that the tibial tuberosity as a reference point for leg circumference measurement has better intraobserver and interobserver agreements than those of the patella and the medial malleoli.
Poststroke Neurogenesis: Emerging Principles of Migration and Localization of Immature Neurons
Authors: Ohab J. J. , Carmichael S. T.
Published: November 2007

Stroke induces proliferation of newly born neurons in the subventricular zone, migration of these immature neurons away from the SVZ, and localization within peri-infarct tissues. These 3 processes of proliferation, migration, and localization constitute distinct spatial and temporal zones within poststroke neurogenesis with distinct molecular and cell-cell signaling environments. Immature neurons migrate after stroke in close association with blood vessels and astrocytic processes, in a process that involves matrix metalloproteinases. This poststroke migration shares similar features with normal neuroblast migration in the rostral migratory stream. Immature neurons localize in the peri-infarct cortex in a neurovascular niche where neurogenesis is causally linked to angiogenesis through the vascular factors SDF-1 and angiopoietin-1. Other vascular and neuronal growth factors have also been linked to poststroke neuroblast localization in peri-infarct tissue, including erythropoietin. Most data on poststroke neurogenesis derive from laboratory rodents, which may have an abnormal or blunted degree of neurogenesis and neuroplasticity compared to normal, wild rodents. This will likely affect translational application of the principles of poststroke neurogenesis from mouse to man. NEUROSCIENTIST 14(4):369–380, 2008. DOI: 10.1177/1073858407309545
Transcription MRI: A New View of the Living Brain
Authors: Liu Philip K. , Mandeville Joseph B. , Guangping Dai  , Jenkins Bruce G. , Kim Young R. , Liu Christina H.
Published: November 2007

Altered gene activities are underlying causes of many neurological disorders. The ability to detect, image, and report endogenous gene transcription using magnetic resonance (MR) holds great potential for providing significant clinical benefits. In this review, we present the development of conjugates consisting of gene-targeting short nucleic acids (oligodeoxynucleotides, or sODN) and superparamagnetic iron oxide nanoparticles (SPION, an MR susceptibility T2 agent) for reporting gene activity using transcription MRI (tMRI). We will discuss 1) the target specificity of sODN, 2) selection of contrast agents for tMRI, 3) the distribution and uptake, 4) sequence specificity, 5) histology of SPION and sODN, 6) data acquisition and quantitative analysis for tMRI, and 7) application of gene transcript—targeting nanoparticles in biology and medicine. We will also discuss methods of validating the correlation between results from conventional assays (in situ hybridization, PCR, histology Prussian blue stain and immunohistochemistry) in postmortem samples and retention of SPION-sODN using tMRI. The application of our novel contrast probe to report and target gene transcripts in the mesolimbic pathways of living mouse brains after amphetamine exposure will be discussed. Because of the targeting ability in the nucleic acid sequence, the concept of tMRI probes with complementary nucleic acid (antisense DNA or short interfering RNA) allows not only tracking, targeting, binding to intracellular mRNA, and manipulating gene action but also tracing cells with specific gene action in living brains. Transcription MRI will lend itself to myriad applications in living organs. NEUROSCIENTIST 14(5):503—520, 2008. DOI: 10.1177/1073858407309746