bluuebunny/crossref_metadata_2025_split huggingface dataset:
Myocardial CXCR4 Expression Is Required for Mesenchymal Stem Cell Mediated Repair Following Acute Myocardial Infarction
Authors: Dong Feng , Harvey James , Finan Amanda , Weber Kristal , Agarwal Udit , Penn Marc S. 
Published: June 2012

Background—
Overexpression of stromal cell-derived factor-1 in injured tissue leads to improved end-organ function. In this study, we quantify the local trophic effects of mesenchymal stem cell (MSC) stromal cell-derived factor-1 release on the effects of MSC engraftment in the myocardium after acute myocardial infarction.

Methods and Results—

Conditional cardiac myocyte CXCR4 (CM-CXCR4) null mice were generated by use of tamoxifen-inducible cardiac-specific cre by crossing CXCR4 floxed with MCM-cre mouse. Studies were performed in littermates with (CM-CXCR4 null) or without (control) tamoxifen injection 3 weeks before acute myocardial infarction. One day after acute myocardial infarction, mice received 100 000 MSC or saline via tail vein. We show α-myosin heavy chain MerCreMer and the MLC-2v promoters are active in cardiac progenitor cells. MSC engraftment in wild-type mice decreased terminal deoxynucleotidyltransferase–mediated dUTP nick-end labeling positive CM (−44%,
P
<0.01), increased cardiac progenitor cell recruitment (100.9%,
P
<0.01), and increased cardiac myosin-positive area (39%,
P
<0.05) at 4, 7, and 21 days after acute myocardial infarction, respectively. MSC in wild-type mice resulted in 107.4% (
P
<0.05) increase in ejection fraction in comparison with 25.9% (
P
=NS) increase in CM-CXCR4 null mice. These differences occurred despite equivalent increases (16%) in vascular density in response to MSC infusion in wild-type and CM-CXCR4 null mice.

Conclusions—
These data demonstrate that the local trophic effects of MSC require cardiac progenitor cell and CM-CXCR4 expression and are mediated by MSC stromal cell-derived factor-1 secretion. Our results further demonstrate and quantify for the first time a specific paracrine mechanism of MSC engraftment. In the absence of CM-CXCR4 expression, there is a significant loss of functional benefit in MSC-mediated repair despite equal increases in vascular density.
Nitroglycerin Fails to Lower Blood Pressure in Redox-Dead Cys42Ser PKG1α Knock-In Mouse
Authors: Rudyk Olena , Prysyazhna Oleksandra , Burgoyne Joseph R. , Eaton Philip 
Published: June 2012

Background—
Although nitroglycerin has remained in clinical use since 1879, the mechanism by which it relaxes blood vessels to lower blood pressure remains incompletely understood. Nitroglycerin undergoes metabolism that generates several reaction products, including oxidants, and this bioactivation process is essential for vasodilation. Protein kinase G (PKG) mediates classic nitric oxide–dependent vasorelaxation, but the 1α isoform is also independently activated by oxidation that involves interprotein disulfide formation within this homodimeric protein complex. We hypothesized that nitroglycerin-induced vasodilation is mediated by disulfide activation of PKG1α.

Methods and Results—

Treating smooth muscle cells or isolated blood vessels with nitroglycerin caused PKG1α disulfide dimerization. PKG1α disulfide formation was increased in wild-type mouse aortas by in vivo nitroglycerin treatment, but this oxidation was lost as tolerance developed. To establish whether kinase oxidation underlies nitroglycerin-induced vasodilation in vivo, we used a Cys42Ser PKG1α knock-in mouse that cannot transduce oxidant signals because it does not contain the vital redox-sensing thiol. This redox-dead knock-in mouse was substantively deficient in hypotensive response to nitroglycerin compared with wild-type littermates as measured in vivo by radiotelemetry. Resistance blood vessels from knock-ins were markedly less sensitive to nitroglycerin-induced vasodilation (EC
50
=39.2±10.7 μmol/L) than wild-types (EC
50
=12.1±2.9 μmol/L). Furthermore, after ≈24 hours of treatment, wild-type controls stopped vasodilating to nitroglycerin, and the vascular sensitivity to nitroglycerin was decreased, whereas this tolerance phenomenon, which routinely hampers the management of hypertensive patients, was absent in knock-ins.

Conclusions—
PKG1α disulfide formation is a significant mediator of nitroglycerin-induced vasodilation, and tolerance to nitroglycerin is associated with loss of kinase oxidation.
A Population-Based Nationwide Study of Cruciate Ligament Injury in Sweden, 2001-2009
Authors: Nordenvall Richard , Bahmanyar Shahram , Adami Johanna , Stenros Carin , Wredmark Torsten , Felländer-Tsai Li 
Published: June 2012

Background: A few national cruciate ligament (CL) registers have been initiated with operative surveillance and outcome monitoring. No nationwide study describing CL injury has ever been done. Purpose: To study the incidence and characteristics of patients diagnosed with cruciate ligament injury in Sweden. Study Design: Descriptive epidemiology study. Methods: Data for all patients with a diagnosed CL injury between 2001 and 2009 were identified from the National Swedish Patient Register. Risk analysis and specific incidences were calculated according to age, sex, geographic region, and surgery. Results: A total number of 56,659 patients with CL injury were included in the study, and the overall incidence of CL injury in Sweden was 78 per 100,000 persons. Sixty percent of the patients were male. The mean age was 32 years (range, 1-98 years), and 50% of the cohort was younger than 30 years. There was an increased rate of injury among female patients younger than 20 years as compared with male patients in that age group. Among patients with CL injury, 36% underwent reconstructive surgery, with one-third of these performed within 1 year after injury. Among patients who underwent surgery, 59% were male; the mean age was 27 years (range, 5-89 years). Conclusion: This study defines the incidence of CL injury and also demonstrates sex differences in which men were more likely to sustain a CL injury, although female patients were injured at an earlier age. The findings in this study corroborate the results from recent surgical registers. Clinical Relevance: No data have hitherto been published including all patients with CL injury, treated both surgically and nonsurgically. Such baseline epidemiologic data are crucial to be able to validate and judge the generalizability of results from procedure registers and clinical studies.
A Stand-Alone Accelerometer System for Free-Living Individuals to Measure and Promote Physical Activity
Authors: Manohar Chinmay U. , Koepp Gabriel A. , McCrady-Spitzer Shelly K. , Levine James A. 
Published: June 2012

Background. Physical activity is important for multiple aspects of health, for example, cancer prevention, metabolic disease treatment, cardiovascular health, and obesity management. Despite the improved capability of measuring physical activity in the research arena, the options are scarce and less reliable for measurements in free-living people. In this article, the authors tested the validity of a robust stand-alone patient-operated Accelerometer System that can measure physical activity and sedentariness in active people. Methods. Thirty subjects wore the Accelerometer System along with the validated physical activity monitoring system (PAMS) with different body postures and during graded walking at 7 velocities. Energy expenditure was measured using indirect calorimetry. Results. In all the 30 subjects, the Accelerometer System distinguished sedentary and walking activity reliably even with ½ mph increments in walking and was accurate and precise compared with PAMS, with an intraclass correlation coefficient ( r2 > .98). The Accelerometer System showed excellent sequential increases with increase in walking velocity and energy expenditure ( r2 > .9). Conclusion. A stand-alone Accelerometer System was accurate and reliable in measuring and quantifying physical activity in the laboratory setting.
Clay crystal-chemical adaptability and transformation mechanisms
Authors: Cuadros J. 
Published: June 2012

AbstractChemical and mineralogical transformations of phyllosilicates are among the most important in diagenetic environments in all types of rocks because they can exert a large control on the processes taking place in such environments and/or provide constraints for the conditions in which phyllosilicate transformation occurred. Dissolution-precipitation and solid-state transformation are usually the two mechanisms proposed for such reactions depending on the crystal-chemical and morphological similarities between parent and neoformed phases together with knowledge of the environmental conditions. These two mechanisms, however, may be at both ends of the spectrum of those operating and many transformations may take place through a mixture of the two mechanisms, generating observable elements that are characteristic of one or the other. In the present literature, the boundaries between the two mechanisms are not clear, mainly because dissolution-precipitation is sometimes defined at nearly atomic scale. It is proposed here that such small-scale processes are considered as a solid-state transformation, and that dissolution-precipitation requires dissolution of entire mineral particles and their dissolved species to pass into the bulk of the solution. Understanding the reaction mechanisms of diagenetic transformations is an important issue because they impinge on geochemical conditions and variables such as cation mobility, rock volume, fabric changes, rock permeability, stable isotope signature and phyllosilicate crystal-chemistry.I propose that, in the lower range temperatures at which clay mineral transformations take place, energy considerations favour solid-state transformation, or reactions that involve the breaking of a limited number of bonds, over dissolution of entire grains and precipitation of crystals of the new phase. Large morphological changes are frequently invoked as evidence for a dissolution-precipitation mechanism but changes in particle shape and size may be achieved by particle rupture, particle welding or by hybrid processes in which dissolution-precipitation plays a minor role.Past and recent studies of phyllosilicate transformations show chemical and structural intermediates indicating a large crystal-chemical versatility, greater than is commonly recognized. These intermediates include tetrahedral sheets of different composition within TOT units (termed polar layers), dioctahedral and trioctahedral domains in the same layer, and 2:1 and 1:1 domains also within the same layers. The existence of such intermediate structures suggests that the reaction mechanisms that generated them are within the realm of the solid-state transformation processes.
Microwave-activated p-TSA dealuminated montmorillonite – a new material with improved catalytic activity
Authors: Ramesh S. , Bhat Y. S. , Jai Prakash B. S. 
Published: June 2012

AbstractWe report a montmorillonite material with enhanced surface area but with very little alteration in cation exchange capacity (CEC) upon dealumination with para toluene sulphonic acid (p-TSA). The new material shows higher catalytic activity in comparison with mineral-acid-treated clay. Montmorillonite clay was treated with p-TSA for 10 minutes under microwave irradiation. The resulting clay was characterized by CEC, X-ray diffraction (XRD), BET analysis, Fourier transform infrared spectroscopy (FT-IR), temperature programmed desorption (TPD) of ammonia and cyclic voltametry (CV) techniques. XRD patterns show an unchanged structure of pristine matrix after the acid action. BET analysis revealed an increase in the surface area and pore volume on p-TSA treatment, indicating formation of voids in the octahedral layer which suggests dealumination. Nitrogen adsorption-desorption curves showed the creation of new micro porous regions, possibly in the octahedral sheets. In contrast to mineral acid treatment, p-TSA treated clay samples showed similar CEC which shows the absence of dissolution of isomorphously substituted Mg and Fe ions present in the octahedral layer. CV studies confirm the formation of an Al-p-TSA complex, suggesting dissolution of aluminium octahedral sheets. The complex subsequently hydrolyses, replacing interlayer cations with Al3+ ions. Similar treatment with mineral acid resulted in clay with enhanced surface area but with reduced CEC, evidently due to the removal of isomorphously substituted Fe and Mg. Further, the p-TSA treated clays showed relatively higher esterification activity under solvent-free microwave irradiation. The p-TSA treated clay retained its activity even after three subsequent runs and thus can be exploited for practical applications.
Adsorption and stacking behaviour of zwitterionic porphyrin on the clay surface
Authors: Eyama T. , Yogo Y. , Fujimura T. , Tsukamoto T. , Masui D. , Shimada T. , Tachibana H. , Inoue H. , Takagi S. 
Published: June 2012

AbstractZwitterionic porphyrin (tetrakis {4-(2-carboxyethyl)pyridinio}porphyrin (TPyCP)) with four pyridinium and carboxyl groups in the molecule was synthesized. The adsorption behaviour of TPyCP on the montmorillonite clay surface was examined in an aqueous colloidal solution. While the adsorption maximum λmax of TPyCP was 424 nm in water, it shifted to longer wavelengths on complex formation with clay. The λmax on the exfoliated clay surface was 450 nm, and that in the stacked clay sheets was 471 nm, respectively. Under alkaline conditions ([NaOH] = 2 × 10–4 M), the stacking behaviour of the clay was completely suppressed. It emerged that anionic parts in the porphyrin molecule can suppress the stacking of clay sheets. Judging from the quantitative analysis, the maximum adsorption amount of TPyCP was 100% vs. cation exchange capacity (CEC) of the clay. As the adsorption density of TPyCP increased, λmax shifted slightly to longer wavelengths due to the interactions between adjacent porphyrins. When the loading level of TPyCP was 200% vs. CEC, the stacking of TPyCP was indicated. The average stacking layer number was calculated to be 1.48. On the other hand, it is known that tetra cationic porphyrins without anionic parts do not form such stacking structures. Thus, it seems that zwitterionic porphyrin has the potential to form a three dimensional structure through electrostatic interactions between porphyrins on the clay surface.
Comparison of argon plasma coagulation in management of upper gastrointestinal angiodysplasia and gastric antral vascular ectasia hemorrhage
Authors: Chiu Yi-Chun , Lu Lung-Sheng , Wu Keng-Liang , Tam William , Hu Ming-Luen , Tai Wei-Chen , Chiu King-Wah , Chuah Seng-Kee 
Published: June 2012

Abstract

Background
Vascular ectasias, including gastric antral vascular ectasia (GAVE) and angiodysplasia, are increasingly recognized as important sources of gastrointestinal bleeding. This study investigated and compared the efficacies and outcomes of treatment of upper gastrointestinal (UGI) angiodysplasia and GAVE hemorrhage by endoscopic argon plasma coagulation (APC).

Methods
From January 2006 to December 2009, 46 patients diagnosed with upper GI bleeding caused by angiodysplasia or GAVE at a tertiary hospital were recruited into this study. They included 26 males and 20 females with an average age of 65.6 years (range, 45–90 years). All patients underwent APC for hemostasis during an endoscopic procedure. Parameters such as underlying co-morbidities, number of endoscopic treatment sessions, recurrent bleeding, and clinical outcomes during follow-up were analyzed.

Results
The 46 patients with UGI vascular ectasia hemorrhage included 27 patients with angiodysplasia and 19 with GAVE. The patients with angiodysplasia were older than those with GAVE (71.6 ± 10.2 years versus 61.8 ± 11.9 years, P = 0.005). More GAVE patients than angiodysplasia patients had co-existing liver cirrhosis (63.2% versus 25.9%, P = 0.012). The patients with GAVE had a higher rate of recurrent bleeding (78.9% versus 7.4%, P < 0.001) and required more treatment sessions to achieve complete hemostasis (2.4 ± 1.4 versus 1.1 ± 0.1, P < 0.001) than those with angiodysplasia. Univariate analysis demonstrated that age greater than 60 years (odds ratio (OR) = 8.929, P = 0.003), GAVE (OR = 0.021, P < 0.001), and previous radiation therapy (OR = 11.667, P = 0.032) were associated with higher rates of recurrent bleeding. Further multivariate analysis revealed that GAVE was the only independent risk factor for recurrent bleeding after APC treatment (OR = 0.027, P < 0.001).

Conclusion
Endoscopic hemostasis with APC is a safe treatment modality for both angiodysplasia and vascular ectasia bleeding. The efficacy of APC treatment is greater for angiodysplasia than for vascular ectasia bleeding. GAVE patients have a higher recurrent bleeding rate and may require multiple treatment sessions for sustained hemostasis.
PA from an H5N1 highly pathogenic avian influenza virus activates viral transcription and replication and induces apoptosis and interferon expression at an early stage of infection
Authors: Wang Qiang , Zhang Shijian , Jiang Hongbing , Wang Jinlan , Weng Leiyun , Mao Yingying , Sekiguchi Satoshi , Yasui Fumihiko , Kohara Michinori , Buchy Philippe , Deubel Vincent , Xu Ke , Sun Bing , Toyoda Tetsuya 
Published: June 2012

AbstractBackgroundAlthough gene exchange is not likely to occur freely, reassortment between the H5N1 highly pathogenic avian influenza virus (HPAIV) and currently circulating human viruses is a serious concern. The PA polymerase subunit of H5N1 HPAIV was recently reported to activate the influenza replicon activity.MethodsThe replicon activities of PR8 and WSN strains (H1N1) of influenza containing PA from HPAIV A/Cambodia/P0322095/2005 (H5N1) and the activity of the chimeric RNA polymerase were analyzed. A reassortant WSN virus containing the H5N1 Cambodia PA (C-PA) was then reconstituted and its growth in cells and pathogenicity in mice examined. The interferon promoter, TUNEL, and caspase 3, 8, and 9 activities of C-PA-infected cells were compared with those of WSN-infected cells.ResultsThe activity of the chimeric RNA polymerase was slightly higher than that of WSN, and C-PA replicated better than WSN in cells. However, the multi-step growth of C-PA and its pathogenicity in mice were lower than those of WSN. The interferon promoter, TUNEL, and caspase 3, 8, and 9 activities were strongly induced in early infection in C-PA-infected cells but not in WSN-infected cells.ConclusionsApoptosis and interferon were strongly induced early in C-PA infection, which protected the uninfected cells from expansion of viral infection. In this case, these classical host-virus interactions contributed to the attenuation of this strongly replicating virus.
A combination extract of ginseng, epimedium, polygala, and tuber curcumae increases synaptophysin expression in APPV717I transgenic mice
Authors: Shi Jing , Tian Jinzhou , Zhang Xuekai , Wei Mingqing , Yin Long , Wang Pengwen , Wang Yongyan 
Published: June 2012

Abstract

Background
The density of presynaptic markers of synaptic communication and plasticity, especially synaptophysin (SYP), is significantly correlated with cognitive decline and the progression of Alzheimer’s disease (AD), indicating that synaptic protection is an important therapeutic strategy for AD. This study aims to investigate the synaptic protective effects of a combination of several active components extracted from the Chinese herbs ginseng, epimedium, polygala and tuber curcumae (GEPT), in the brains of APPV717I transgenic mice.

Methods
Three-month-old APPV717I mice were arbitrarily divided into 10 groups (n = 12 per group): APP groups receiving vehicle treatment for four or eight months (model groups), three dose groups of GEPT-treated mice for each treatment period, and donepezil-treated mice for each treatment period. Three-month-old C57BL/6 J mice (n = 12) were also given vehicle for four or eight months (control groups). Vehicle, donepezil or GEPT were intragastrically administered. Immunohistochemistry (IHC) and Western blot analysis were used to assess protein expression in the hippocampal CA1 region and ratios of SYP to β-actin levels in hippocampal tissue homogenate, respectively.

Results
Both IHC and Western blot revealed a decrease in SYP levels in the CA1 region of 7- and 11-month-old APPV717I transgenic mice compared with the control groups, whereas SYP levels were increased in donepezil- and GEPT-treated transgenic mice compared with the APP group. There was a significant difference in the levels of SYP detected by IHC between the GEPT high-dose group and the APP group after 4 months of treatment, and there were significant differences between all three GEPT groups and the APP group after 8 months of treatment. Western blotting showed that the SYP protein–β-actin ratio was decreased in APP mice, while donepezil- and GEPT-treated transgenic mice showed increased trends in the SYP protein–β-actin ratios.

Conclusion
GEPT increases SYP expression and protects synapses before and after the formation of amyloid plaques in the brains of APPV717I transgenic mice.
Pharmacokinetics of an injectable long-acting formulation of doxycycline hyclate in dogs
Authors: Gutiérrez Lilia , Velasco Zazil-Ha , Vázquez Carlos , Vargas Dinorah , Sumano Héctor 
Published: June 2012

Abstract
Based on its PK/PD ratios, doxycycline hyclate (DOX-h), a time-dependant antibacterial, is ideally expected to achieve both sustained plasma drug concentrations at or slightly above the MIC level for as long as possible between dosing intervals. Pursuing this end, a poloxamer-based matrix was used to produce a long-acting injectable preparation (DOX-h-LA) and its serum concentrations vs. time profile investigated after its SC injection to dogs (≤ 0.3 mL per injection site), and results compared with the oral (PO) and IV pharmacokinetics of DOX-h, prepared as tablet or as freshly made solution. A crossover (4 x 4 x 4) study design was employed with 12 Mongrel dogs, with washout periods of 21 days, and at dose of 10 mg/kg in all cases. DOX-h-LA showed the greatest values for bioavailability (199.48%); maximum serum concentration (Cmax) value was 2.8 ± 0.3 with a time to reach Cmax (Tmax) of 2.11 ± 0.12 h and an elimination half-life of 133.61 ± 6.32 h. Considering minimum effective serum concentration of 0.5 μg/mL, a dose-interval of at least 1 week h can be achieved for DOX-h-LA, and only 48 h and 24 h after the IV or PO administration of DOX-h as a solution or as tablets, respectively. A non-painful small bulge, apparently non-inflammatory could be distinguished at injection sites. These lumps dissipated completely in 30 days in all cases.