bluuebunny/crossref_metadata_2025 huggingface dataset:
Remodeling of Capillary Network in Left Ventricular Subendocardial Tissues Induced by Intravenous Vasopressin Administration
Authors: Xie Zhonglin , Gao Ming , Batra Sanjay , Koyama Tomiyasu
Published: April 2008

Objective: The question of whether the coronary vasospasm induced by intravenous administration of vasopressin produces any remodeling of the capillary network in the left ventricle was investigated. To this end, cardiac tissues obtained from vasopressin‐injected rats were stained to allow capillary counting and for basic fibroblast growth factor (bFGF).

Methods: Nine male Donryu rats were divided into three groups that received, respectively, 0.25 ml of saline containing 0, 0.5, or 1.0 U/kg vasopressin injected into the tail vein once daily for 4 days. Rats were killed 30 days after the last injection. Two additional rats each received a single intravenous injection of 1.0 U/kg vasopressin and were killed 24 hours later. The left ventricles were removed and 16‐ or 10‐μm frozen sections were cut for differential staining and distribution of bFGF, respectively. Differential staining was used to classify the capillary portions, and bFGF was identified by immunohistological staining.

Results: Compared with the control group, total capillary density was increased in both vasopressin‐treated groups, capillary to myocyte ratio was increased, and the capillary domain areas decreased in the three capillary portions. Arteriolar and intermediate capillary portions increased, while the venular capillary portion decreased. In rats killed 24 hours after vasopressin injection, a considerable amount of bFGF could be demonstrated immunohistochemically in the ventricular tissues, and the punctate distribution of bFGF was still found in rats killed 30 days after treatment.

Conclusions: A remodeling of capillary network which would increase the oxygen transport capacity to cardiac tissues was produced in left ventricular tissues by intravenous injection of vasopressin. bFGF located around capillaries and in the interstitial space may have been involved in the capillary remodeling.
Vascular Endothelial Cadherin (VE‐Cadherin): Cloning and Role in Endothelial Cell‐Cell Adhesion
Authors: Ali Jahanara , Liao Fang , Martens Eric , Muller William A.
Published: April 2008

Objective: To identify proteins responsible for intercellular junction integrity in human umbilical vein endothelial cells (HUVEC), we produced a monoclonal antibody that recognized an endothelial cell‐specific, junctionally restricted protein. We characterized and cloned the antigen to study its functional properties.

Methods: The size and cellular distribution of the antigen were determined by immunofluorescence and immunoprecipitation. The molecule was cloned and transfected into cell lines, and its role in cell‐cell adhesion and growth rate was determined.

Results: Monoclonal antibody heel recognizes VE‐cadherin, an endothelial cell‐restricted cell adhesion molecule. VE‐cadherin is localized to the borders between apposing endothelial cells but is diffusely distributed on subconfluent or migrating cells. Transfection of fibroblasts with VE‐cadherin imparts to them the ability to adhere to each other in a calcium‐dependent homophilic manner. Expression of VE‐cadherin over a several‐log range does not change the growth rate of these cells.

Conclusions: Despite the fact that VE‐cadherin is a “nonclassical” cadherin by structure, it functions as a classic cadherin by imparting to cells the ability to adhere in a calcium‐dependent, homophilic manner. On HUVEC it appears to play a role in maintaining monolayer integrity.
Shear Rate Dependency of Red Cell Sequestration in Skin Capillaries in Sickle Cell Disease and Its Variation with Vasoocclusive Crisis
Authors: Lipowsky Herbert H. , Williams Melanie E.
Published: April 2008

Objective: To develop techniques for assessing the sequestration of red blood cells (RBCs) in skin capillaries of sickle cell disease (SCD) patients due to RBC adhesion to endothelium (EC) and RBC aggregation, and to determine the extent to which these processes correlate with onset of painful vasoocclusive crisis.

Methods: Video recordings of nailfold capillaries in the skin of patients with SCD were made during steady‐state periods and episodes of painful crisis. A transient low‐flow state was induced with a pressure cuff, and reductions in RBC velocity were measured by spatial cross‐correlation of light intensity along arterial and venous capillary limbs. An RBC accumulation index (AI) was calculated from RBC flow to represent the percentage of arterial in‐flow sequestered in a capillary. An index of hematocrit (HI) was derived from axial distributions of light intensity, and a sequestration index (SI) was calculated to represent the relative increase of venous limb HI relative to that in the arterial limb with onset of stasis.

Results: Both AI and SI increased dramatically from zero at steady flow to a maximum as shear rates within the capillary were reduced to zero. The increase was small until shear rates (γ) fell below a transition value (γT), following which both AI and SI increased sharply with onset of stasis. For 20 ≤ γ < γT the transient increase in AI was significantly elevated in the order AICRISIS > AISTEADY STATE > AICONTROL, thus reflecting increasing RBC sequestration in the venous limb due to either adhesion or aggregation. Compaction of RBCs in the venous limb was evidenced by increased SI that was greater than control for both steady‐state and crisis subjects, but insignificantly elevated during crisis compared to steady state, thus supporting a lesser role of RBC aggregation.

Conclusions: Transient sequestration of sickle RBCs in the low‐flow state appears to be dominated by RBC‐EC adhesion, which becomes enhanced during crisis. Although aggregation may enhance adhesive contact of RBCs with EC, it does not increase to the same extent as the rate of sequestration, thus reflecting a greater role of RBC‐EC adhesion.
The Cutaneous Microcirculation: Ultrastructure and Microanatomical Organization
Authors: Braverman Irwin M.
Published: April 2008

The cutaneous microcirculation is organized as two horizontal plexuses. One is situated 1–1.5 mm below the skin surface, and the other is at the dermal‐subcutaneous junction. Ascending arterioles and descending venules are paired as they connect the two plexuses. From the upper layer, arterial capillaries arise to form the dermal papillary loops that represent the nutritive component of the skin circulation. There are sphincter‐like smooth muscle cells at the point where the ascending arterioles divide to form the arteriolar component of the upper horizontal plexus. At the dermal subcutaneous junction, there are collecting veins with 2‐cusped valves that are oriented to prevent the retrograde flow of blood. Laser Doppler flowmetry (LDF) has demonstrated vasomotion of red cell flux localized to the sites of ascending arterioles. The simultaneous recording by LDF of red cell flux and the concentration of moving red blood cells from individual sites allows one to construct by computer topographic maps of these two valves. The two maps, based on initial studies using correlative skin biopsy specimens, can define 1‐mm3 volumes of skin that are predominantly arteriolar in composition, predominantly venular in composition, or essentially devoid of all microvascular elements. The electron and light microscopic features that define the microvascular segments, when coupled with the ability of LDF to define the predominant microvascular segments under the probe, will allow one to study both the mechanisms of normal physiological states and the pathogenetic mechanisms underlying pathological skin disorders in which the microvasculature plays a predominant role.
Redox Control of Ion Channel Activity in Vascular Endothelial Cells by Glutathione
Authors: Elliott Stephen J. , Koliwad Suneil K.
Published: April 2008

Oxidized glutathione (GSSG) is endogenously formed within vascular endothelial cells. The bioactivity of GSSG results in the oxidation of protein thiol groups, leading to changes in protein structure‐function relationships. When ion channel protein thiols are the target of oxidation by GSSG, important changes in channel conductance, activity, and gating occur. In this review, we focus on two endothelial cell ion channels, the activities of which influence vascular cell signaling and the nitric oxide signaling pathway. The first channel is the GSSG‐operated cation channel that depolarizes the endothelial cell, leading to inhibition of capacitative Ca2+ entry. The second channel is the inositol 1,4,5‐triphosphate (IP3)‐operated Ca2+ channel that is responsible for the agonist‐stimulated release of Ca2+ from IP3‐sensitive endoplasmic reticulum. GSSG acts to deplete IP3‐sensitive Ca2+ stores, thereby attenuating the intracellular Ca2+ response to agonist stimulation. Together, these effects indicate that glutathione, which is formed endogenously within the cell, is a key physiological modulator of endothelial cell signaling.
Lung Neutrophil Retention and Injury After Intestinal Ischemia/Reperfusion
Authors: Xiao Feng , Eppihimer Michael J. , Young Jay A. , Nguyen Khoa , Carden Donna L.
Published: April 2008

Objective: To define the mechanisms responsible for the lung leukosequestration and injury elicited by intestinal ischemia/reperfusion (I/R).

Methods: The effect of 120 minutes of superior mesenteric artery occlusion and 90 minutes of reperfusion on neutrophil deformability, lung neutrophil retention, and pulmonary microvascular permeability was determined.

Results: Compared with control surgery, intestinal I/R resulted in a significant increase in neutrophil stiffness (mean yield pressure [Pyieid], 1–533 ± 0.075 and 2.302 ± 0.288 cm H2O, respectively) and lung neutrophil content (6.3 ± 1.4 and 31.5 ± 6.4 U/g wet weight, respectively). These changes were not affected by inhibition of neutrophil adherence before gut reperfusion. However, the increased lung microvascular permeability elicited by gut I/R (0.111 ± 0.020 [control surgery] and 0.255 ± 0.041 [I/R] mL/min/cm H2O/100 g lung tissue) was significantly attenuated by administration of antibodies directed against neutrophil or endothelial determinants of leukocyte adhesion.

Conclusions: The results of this study suggest that intestinal I/R is a potent inflammatory stimulus that elicits an increase in neutrophil stiffness and lung neutrophil retention independent of neutrophil‐endothelial cell adhesion. In contrast, the increased lung microvascular permeability elicited by gut I/R is attenuated by strategies that interfere with neutrophil‐endothelial cell adhesion.
Myogenic Responses of Isolated Lymphatics: Modulation by Endothelium
Authors: Mizuno Risuke , Dörnyei Gabriella , Koller Akos , Kaley Gabor
Published: April 2008

Objective: To characterize the effect of increases of intraluminal pressure on the spontaneous diameter oscillations of isolated lymphatics and on the maximum and minimum diameter, in the presence and absence of endothelium.

Methods: Afferent lymphatics were isolated from rat iliac lymph nodes. After cannulation of both ends, lymphatics were equilibrated for 60 minutes at a pressure of 6 cm H2O, and then changes in diameter oscillations to increases in perfusion pressure (from 2–10 cm H2O) were measured. The endothelium was removed by intraluminal infusion of air. Changes in diameter were expressed as a percentage of the corresponding passive diameter obtained in Ca2+‐free solution.

Results: Isolated lymphatics showed phasic spontaneous constriction and dilation (∼50 to ∼150 μm). Removal of extracellular Ca2+ abolished spontaneous diameter oscillations, and the passive diameter increased from 183.0 ± 5.3 to 205.1 ± 8.8 μm as pressure increased from 2 to 10 cm H2O. In response to increases in pressure, the normalized minimum diameter (Dmin) increased (from 30.1% ± 1.1% to 54.8% ± 1.9%) while the normalized maximum diameter (Dmax) of lymphatics did not change. With increasing pressure the amplitude of vasomotion (Dmax‐Dmin) decreased, whereas the oscillation frequency increased. Removal of endothelium significantly reduced Dmax; hence, the oscillation amplitude decreased while the frequency increased. Also, endothelium removal elicited a significant change in the slope of the pressure‐Dmax curve (from 0.01 ± 0.4 to −1.43 ± 0.34).

Conclusions: Increases in intraluminal pressure greatly affect the spontaneous vasomotion of lymphatics and activate the myogenic mechanism intrinsic to the smooth muscle. In addition, endothelial factors are important to maintain adequate lymphatic vasomotion. These findings suggest that intraluminal pressure and endothelial factors can be important contributors to the tone and pumping activity of lymphatics in vivo.
Mechanical Remodeling of the Endothelial Surface and Actin Cytoskeleton Induced by Fluid Flow
Authors: Satcher Robert , Dewey C. Forbes , Hartwig John H.
Published: April 2008

Objective: The mechanism by which cultured endothelial cells respond to shear stress is controversial. The cell surface and cytoskeleton are involved, but their roles are undefined. In this study, previously unknown changes in the surface detail and actin cytoskeleton of bovine aortic endothelial cells were identified.

Methods: Actin filament content and filament number in resting and flow‐oriented cells were determined by biochemical assays. The three‐dimensional organization of the actin cytoskeleton in cells was defined in the confocal microscope and in the electron microscope after rapid‐freezing, freeze‐drying, and metal coating of detergent‐permeabilized cells.

Results: Endothelial cells have smooth apical membranes in situ. However, cultured cells exhibit surface microvilli which increase the apical surface area, exposing the ruffled surface to forces from fluid flow and potentially enhancing cell interactions with blood‐borne white cells. Stereoscopic micrographs show that stress fibers are integrated into a complex distributed cytoplasmic structural actin network (DCSA). This lattice is formed by actin filaments that frequently cross and connect to each other, stress fibers, and microfilaments and microtubules. The cytoskeletons of cells cultured in static media lack apparent order when compared to cytoskeletons from cells which have been exposed to 24 hours of laminar flow.

Conclusions: The DCSA physically connects the apical and basal cell membranes and fills the volume between nucleus and membrane, providing a mechanism for transmitting mechanical forces across cells and a signaling pathway from membrane to nucleus. Stress fibers increase the mechanical modulus of the DCSA, although this increase is probably unnecessary to withstand the increase in shear stress caused by blood flow in vivo. This implies that actin rearrangements are not required for mechanical integrity, but serve an alternate function.
A Semiautomatic Procedure for Edge Detection of In Vivo Pulmonary Microvessels and Interstitial Space
Authors: Crisafulli Beatrice , Boschetti Federica , Venturoli Daniele , Del Fabbro Massimo , Miserocchi Giuseppe
Published: April 2008

Objective: To develop an algorithm to detect the edges between lung tissue, perivascular interstitium. and microvessel using digital processing of in vivo microscopic images of lung surface.

Methods: A numerical technique was developed to identify three different regions (namely, pulmonary microvessel, perivascular interstitium, and lung tissue) based on their corresponding gray level distributions. We present a theoretical demonstration of the method and a semiautomatic procedure that, once the edges are detected, determines microvascular diameters and perivascular interstitium thickness.

Results: Microvessel diameters and perivascular interstitium thickness were calculated for precapillary arteriolar branching (40 to 140 μm) and saved in an ASCII file.

Conclusions: We proved that the maximum value of the moving variance is useful to detect the edge between two adjacent regions whose gray level distributions satisfy the condition: ∥σY2‐σX2∥ ≤ (μX‐μY)2, where μX, μY, σX2, σY2 are the statistical moments of the two regions X and Y. Moreover, when the regions have similar means, the above condition is not met, but the edge between them can be detected by the maximum of the moving variance error.
Geometric Resistance and Microvascular Network Architecture of Human Colorectal Carcinoma
Authors: Less Joanne R. , Posner Mitchel C. , Skalak Thomas C. , Wolmark Norman , Jain Rakesh K.
Published: April 2008

Objective: To measure the geometric resistance to blood flow in human colorectal carcinoma. Although tumor blood flow is of central importance in both the detection and the treatment of cancer, the determinants of blood flow through the neoplastic circulation are poorly understood.

Methods: Human colorectal carcinomas (tissue weight = 272 g ± 43 g (SD), n = 6) were perfused ex vivo with a buffered physiological salt solution of known viscosity at flow rates ranging from 2.5 to 40 ml/min and perfusion pressures from 8 to 100 mm Hg. The geometric resistance was determined from the slope of the pressure‐flow curve. For examination of the principal determinant of geometric resistance, the vascular architecture, one of the tumors was perfused with Batson's No. 17 polymer and macerated in KOH to produce a positive vascular cast that was used for measurement of vascular branching patterns and dimensions.

Results: The pressure‐flow relationship was linear at perfusion pressures above 40 mm Hg, and the geometric resistance, z0, was constant at approximately 6.5 ± 109g/cm3. Below 40 mm Hg, z0 increased rapidly. The architecture of the arteriolar and capillary networks of human colorectal carcinoma is similar to those of experimental rodent tumors. Capillaries in planar and nonplanar mesh‐works had mean segment diameters of 11 ± 2 and 9.6 ± 2 μm, lengths of 46 ± 24 and 107 ± 40 μm, and intercapillary distances of 46 ± 13 and 74 ± 24 μm, respectively.

Conclusions: The geometric flow resistance in neoplastic tissue is 1–2 orders of magnitude higher than that observed in normal tissues. A decrease in functional vascular cross‐sectional area may explain the additional increase in resistance at small perfusion pressures. The observed flow resistance may be due to the specialized arteriolar and capillary network architecture, pressures exerted by proliferating cancer cells, and/or coupling between vascular and extravascular flow. These observations demonstrate that tumor vascularity alone may not be indicative of flow resistance or tumor susceptibility to blood‐borne therapeutic agents.
Enzymatic Isolation and Characterization of Single Vascular Smooth Muscle Cells from Cremasteric Arterioles
Authors: Jackson William F. , Huebner James M. , Rusch Nancy J.
Published: April 2008

Objective: The goal of the present study was to develop a method to isolate viable arteriolar muscle cells from single cremasteric arterioles, which retain the contractile and electrophysiological phenotype of the donor microvessels.

Methods: Arterioles were hand‐dissected from rat and hamster cremaster muscles and dissociated by incubation in papain and dithioerythritol for 35 min followed by incubation in collagenase, elastase, and soybean trypsin inhibitor for 10 to 25 min in solutions containing 100 μM Ca2+, 10 μM sodium nitroprusside, and 1 mg/ml albumin at 37°C.

Results: Populations of single smooth muscle cells enzymatically isolated from cremasteric arterioles showed elongated fusiform morphology and intact plasmalemmal membranes as indicated by retention of calcein, by exclusion of ethidium ho‐modimer‐1, and by high membrane resistances (11 ± 0.8 Cω, n = 36 for rat cells: 8 ± 0.6 Cω, n = 21 for hamster cells: p < 0.05). Muscle cells contracted in a concentration‐dependent fashion in response to pipette application of norepinephrine (10 nM‐100 μ). Cell shortening in response to 1 μM norepinephrine was inhibited by 10 μM phentolamine, 1 μM sodium nitroprusside, and 1 μM nifedipine or nominally Ca2+‐free media. Resting membrane potential recorded in patch‐clamped cells by perforated patch methods was −48 ± 1 mV (n = 47) for rat cells and −44 ± 2.8 mV (n = 14) for hamster cells (p > 0.05). Families of voltage‐dependent K+ currents were observed during stepwise depolarizing pulses from −60 mV to more positive potentials. Blockers of voltage‐gated and ATP‐sensitive K+ channels (4‐aminopyridine [3 mM] and glibenclamide [1 μM], respectively) inhibited membrane K+ conductance, increased membrane resistance, and depolarized cells by 20 ± 4 mV (n = 8) and 14 ± 3 mV (n − 6), respectively.

Conclusions: The present method permits isolation of smooth muscle cells from a single cremasteric arteriole. These cells seem to retain the contractile phenotype, α‐adrenergic signaling cascade, membrane potential, and K+ conductances described for the donor arteriole. Correlating the functional and electrophysiological properties of these smooth muscle cells to in situ and in vitro studies of their donor arterioles should provide a useful extension for understanding the physiology, patho‐physiology, biophysics, and cell biology of the microcirculation in skeletal muscle.
Changes in Subcutaneous Interstitial Fluid Pressure, Tissue Oxygenation, and Skin Red Cell Flux during Venous Congestion Plethysmography in Men
Authors: Christ F. , Dellian M. , Goetz A. E. , Gamble J. , Messmer K.
Published: April 2008

Objective: Venous congestion plethysmography enables noninvasive assessment of microvascular filtration capacity (Kf) in limbs. However, increases in fluid filtration might alter the balance of Starling forces; for example, progressive increases in interstitial fluid pressure (Pi) would reduce net fluid flux, thus underestimating Kf. Furthermore, elevation of cuff pressure to values close to diastolic blood pressure, as used in the protocol, may by itself impair tissue perfusion with unknown effects on the microvascular parameters investigated.

Methods: Pi was measured in healthy volunteers (n = 14) with a modified “Wick in needle” technique during small (8 mm Hg) cumulative increases in venous pressure (0–95 mm Hg). Changes in the hemoglobin (Hb) concentration, oxygenated hemoglobin (HbO2) concentration, and oxidized cytochrome aa3 concentration were assessed in the calf using noninvasive near‐infrared spectroscopy. Skin red blood cell flux close to the strain gauge was evaluated by laser Doppler fluxmetry.

Results: Pi at control was −0.89 ± 0.8 mm Hg and during elevation of venous pressure remained constant until a cuff pressure of 30 mm Hg was reached. It rose thereafter to 1.57 ± 1.3 mm Hg (mean SD). Skin red cell flux was significantly reduced when cuff pressure exceeded 30 mm Hg and, following cuff deflation, evidence of reactive hyperemia was obtained. Hb concentration increased significandy as a result of venous pressure elevation. No change in either HbO2 or cytochrome aa3 concentration was observed as long as cuff pressure remained under diastolic blood pressure.

Conclusions: The small increase in Pi together with an absence of impaired tissue oxygenation during the venous congestion plethysmography protocol described by Gamble et al. supports the contention mat this protocol enables accurate assessment of filtration capacity.
Preoperative localization of parathyroid lesions
Authors: Mirallié E. , Carlier T. , Abbey-Huguenin H. , Aubron F. , Kraeber-Bodéré F. , Ansquer C.
Published: April 2008

The aim of our study was to assess retrospectively the value of 99mTc-MIBI SPECT in the localization of parathyroid lesions in primary hyperparathyroidism and to determine the impact of PTH level, age, sex, characteristics of the lesions and thyroid nodules on the sensitivity of imaging. Patients, methods: Fifty nine patients who were cured after the resection of 60 lesions (50 adenomas, 9 hyperplasias and 1 carcinoma, 9 of them in ectopy) were selected. 99mTcO4-, early and late 99mTc-MIBI planar images (n = 59), 99mTc-MIBI SPECT (n = 58) and ultrasound (n = 50) performed preoperatively were analyzed. The imaging results were compared to surgical and histological findings and correlated to different factors suspected of influencing the imaging's sensitivity. Results: Sensitivity of double phase 99mTc-MIBI/99mTcO4- scintigraphy was higher than that of early or late scintigraphy alone. SPECT increased the sensitivity of scintigraphy from 85% to 92% and was useful to confirm doubtful foci and to localize ectopic lesions. Ultrasound (US) had the lowest sensitivity (56%) and the highest rate of false-positive results (n = 10), but identified 2 adenomas which were not detected by scintigraphy. Combining all imaging modalities, sensitivity reached 96%. Better sensitivities were observed when age < 69 years, preoperative PTH level ≥155 pg/ml, weight of the gland ≥0.80 g and in the absence of thyroid nodules. US was more influenced by these factors than scintigraphy. Conclusion: Combination of US, double-phase 99mTc- MIBI/99mTcO4- planar scintigraphy and SPECT is the most accurate method for the detection of parathyroid lesions and should be performed before minimally invasive surgery, especially when PTH level is low, in older patients and in cases of multinodular goiter.
Long-term follow-up of metabolic activity in human alveolar echinococcosis using FDG-PET
Authors: Reuter S. , Grüner B. , Buck A. K. , Blumstein N. , Reske S. N. , Kern P.
Published: April 2008

Aim: [18F]fluoro-deoxyglucose positron-emission-tomography (FDG-PET) detects metabolic activity in alveolar echinococcosis (AE). The slow changes in metabolic and morphological characteristics require long-term follow-up of patients. This is the first study to evaluate metabolic activity over may years, hereby assessing the utility of FDGPET for the evaluation of disease progression and response to treatment. Patients, methods: 15 patients received a follow-up FDG-PET combined with computed tomography (integrated PET/CT) with a median of 6.5 years after the first PET in 1999. Number and location of enhanced metabolic activity in the area of AE lesions was determined. Quantification of intensity of metabolic activity was assessed by calculation of mean standardized uptake values. Results: AE lesions in 11/15 patients had been metabolically inactive initially, but only two showed permanent inactivity over the course of 81 months. Interestingly, in two patients metabolic activity was newly detected after 80 and 82 months. Benzimidazole treatment was intermittently discontinued in seven cases. Persisting activity at FDG-PET demanded continued benzimidazole treatment in four patients. Neither treatment duration, lesional size, calcifications nor regressive changes correlated with metabolic activity. Conclusion: Treatment responses are heterogeneous and vary from progressive disease despite treatment to long-term inactive disease with discontinued treatment. Lack of metabolic activity indicates suppressed parasite activity and is not equivalent to parasite death. However, metabolic activity may remain suppressed for years, allowing for temporary treatment discontinuation. Relapses are reliably detected with PET and restarting benzimidazole treatment prevents parasite expansion.
Graves' disease and radioiodine therapy
Authors: Weber I. , Eschner W. , Sudbrock F. , Schmidt M. , Dietlein M. , Schicha H. , Kobe C.
Published: April 2008

Aim: This study was performed to analyse the impact of the choice of antithyroid drugs (ATD) on the outcome of ablative radioiodine therapy (RIT) in patients with Graves' disease. Patients, material, methods: A total of 571 consecutive patients were observed for 12 months after RIT between July 2001 and June 2004. Inclusion criteria were the confirmed diagnosis of Graves' disease, compensation of hyperthyroidism and withdrawal of ATD two days before preliminary radioiodine-testing and RIT. The intended dose of 250 Gy was calculated from the results of the radioiodine test and the therapeutically achieved dose was measured by serial uptake measurements. The end-point measure was thyroid function 12 months after RIT; success was defined as elimination of hyperthyroidism. The pretreatment ATD was retrospectively correlated with the results achieved. Results: Relief from hyperthyroidism was achieved in 96 % of patients. 472 patients were treated with carbimazole or methimazole (CMI) and 61 with propylthiouracil (PTU). 38 patients had no thyrostatic drugs (ND) prior to RIT. The success rate was equal in all groups (CMI 451/472; PTU 61/61; ND 37/38; p=0.22). Conclusion: Thyrostatic treatment with PTU achieves excellent results in ablative RIT, using an accurate dosimetric approach with an achieved post-therapeutic dose of more than 200 Gy.
The simplified reference tissue model for SPECT/PET brain receptor studies
Authors: Thiele F. , Buchert R.
Published: April 2008

Aim: The SRTM (simplified reference tissue model) of brain receptor imaging assumes that the time activity curve in the receptor-rich region of interest can be fitted satisfactorily by the 1-tissue compartment model. This assumption has been formulated by a rather restrictive constraint on the rate constants. Empirically, the SRTM might well describe also tracers which do not fulfil this constraint, such as [11C]raclopride, for example. However, this has not been justified rigorously. Methods: The requirements for the SRTM to be applicable are analyzed in detail. Results: The SRTM is applicable under a less restrictive constraint than described previously. The interpretation of the SRTM parameters R1 and K2 in physiological terms depends on the constraint, while the interpretation of BPND does not. Conclusion: Correct interpretation of the results of the SRTM is tracer specific. In particular, the parameter R1, which in case of compliance with the original constraint might be used to detect perfusion and/or extraction effects, might not be appropriate for this purpose in case of raclopride-like tracers.
Differentiation of Human Erythroid Cells in Culture
Authors: Fibach E. , Prus E.
Published: April 2008

A culture procedure for growing erythroid progenitors in liquid medium is described. The procedure is divided into two phases. The first is an erythropoietin (EPO)–independent phase in which peripheral blood mononuclear cells are isolated and cultured in the presence of a combination of growth factors, but in the absence of EPO. During this phase, early erythroid‐committed progenitors proliferate and differentiate into more mature progenitors. In the second phase, the latter cells, cultured in an EPO‐supplemented medium, continue to proliferate and mature into hemoglobin‐containing nucleated erythroid cells. The culture procedure yields populations that are large, relatively pure, and synchronized (in terms of differentiation), and which recapitulate in vivo erythropoiesis. Since the cells are grown in suspension, samples of cells can be withdrawn at any time, without disturbing the cultures, and assayed for various parameters, e.g., morphology, size, number, viability, apoptosis, cell cycle, surface antigens, or gene expression. Several procedures for analyzing the cultured cells with respect to their hemoglobin content during their differentiation are included.
Hybrid composite based on poly(vinyl alcohol) and fillers from renewable resources
Authors: Cinelli Patrizia , Chiellini Emo , Imam Syed H.
Published: April 2008

Hybrid composite laminates consisting of polyvinyl alcohol (PVA) as continuous phase (33% by weight) and lignocellulosic fillers, derived from sugarcane bagasse, apple and orange waste (22% by weight) were molded in a carver press in the presence of water and glycerol such as platicizers agents. Corn starch was introduced as a biodegradation promoter and gluing component of the natural filler and synthetic polymeric matrix in the composite (22% by weight). The prepared laminates were characterized for their mechanical properties and degradative behavior in simulated soil burial experiments. The fibers type and content in composite impacted mechanical properties. Materials based on PVA and starch with apple wastes and sugarcane bagasse fillers were much harder (Young's Modulus respectively, 57, 171 MPa) than materials prepared with orange wastes (17 Mpa). Respirometric test revealed that soil microbes preferentially used natural polymers and low molecular weight additive as a carbon source compared to biodegradable synthetic polymer. The presence of PVA in formulations had no negative effect on the degradation of lignocellulosic fibers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Teaching image processing: A two‐step process
Authors: Yapp Clarence Han‐Wei , See Alex Kok Bin
Published: April 2008

An interactive program for teaching digital image processing techniques is presented in this article. Instead of heavy programming tasks and mathematical functions, students are led step by step through the exercises and then allowed to experiment. This article evaluates the proposed program and compares it with existing techniques. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 211–222, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20149
Cellular Dynamics of Ku: Characterization and Purification of Ku‐eGFP
Authors: Merkle Dennis , Zheng Dan , Ohrt Thomas , Crell Karin , Schwille Petra
Published: April 2008

Ku is a predominantly nuclear protein that functions as a DNA double‐strand‐break (DSB) binding protein and regulatory subunit of the DNA‐dependent protein kinase (DNA‐PK). DNA‐PK is involved in synapsis and remodeling of broken DNA ends during nonhomologous end‐joining (NHEJ) of DNA DSBs. It has also recently been demonstrated that Ku plays roles in cytoplasmic and membrane processes, namely: interaction with matrix metalloproteinase 9, acting as a co‐receptor for parvoviral infection, and also interacting with cell polarity protein, Par3. We present a method for creating stable expression of Ku‐eGFP in CHO cells and extend the procedure to purify Ku‐eGFP for in vitro assaying. We demonstrated that Ku‐eGFP localizes to the nucleus of HeLa cells upon microinjection into the cytoplasm as well as localizing to laser induced DNA damage. We also characterized the diffusional dynamics of Ku in the nucleus and in the cytoplasm using fluorescence correlation spectroscopy (FCS). The FCS data suggest that whereas the majority of Ku (70 %) in the nucleus is mobile and freely diffusing, in a cellular context, there also exists a significant slow process fraction (30 %). Strikingly, in the cytoplasm, this immobile/slow moving fraction is even more pronounced (45 %).
On the Mechanisms of Degenerate Ligand Exchange in [M(CH3)]+/CH4 Couples (M=Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt) as Explored by Mass Spectrometric and Computational Studies: Oxidative Addition/Reductive Elimination versus σ‐Complex‐Assisted Metathesis
Authors: Armélin Marc , Schlangen Maria , Schwarz Helmut
Published: April 2008

The degenerate ligand exchange in [M(CH3)]+/CH4 couples occurs in the gas phase at room temperature for M=Ni, Ru, Rh, Pd, and Pt, whereas the complexes containing Fe and Co are unreactive. Details of hydrogen‐atom scrambling versus direct ligand switch have been uncovered by labeling experiments with CD4 and 13CH4, respectively. The reactivity scale ranges from unreactive (M=Fe, Co) or inefficient (M=Ni, Pd) to moderately (M=Ru) and rather reactive (M=Rh, Pt). Quite extensive, but not complete, H/D exchange between the hydrogen atoms of the incoming and outgoing methyl groups is observed for M=Pt, whereas for M=Ni and Pd a predominantly direct ligand switch prevails. DFT calculations performed at the B3LYP level of theory account well for the thermal nonreactivity of the Fe and Co couples. For [Ni[CH3)]+/CH4, a σ‐complex‐assisted metathesis (σ‐CAM) is operative such that, in a two‐state reactivity (TSR) scenario, two spin flips between the 3A ground and 1A excited states take place at the entrance and exit channels of the encounter complexes. For M=Ru and Rh, only oxidative addition/reductive elimination (OA/RE) is favored energetically, and the reaction is confined to the electronic ground states 3A and 2A. In contrast, for the [Pd(CH3)]+/CH4 system, on the 1A ground‐state potential‐energy surface both the OA/RE and σ‐CAM variants are energetically comparable, and the small reaction efficiency for the ligand switch is reflected in transition states located energetically close to the reactants. For the [M(CH3)]+/CH4 complexes of the 5d elements, the σ‐CAM mechanism does not play a role. For M=Pt, the energetically most favored path proceeds in a spin‐conserving manner on the 1A potential‐energy surface, which accounts for the extensive single and double hydrogen‐atom exchange preceding ligand exchange. Although for M=Os and Ir the [M(CH3)]+ complexes could not be generated experimentally, computational studies predict that both systems may undergo thermal reaction with CH4, and an OA/RE mechanism will commence on the respective high‐spin ground states; however, the bond‐activation and ligand‐exchange steps will occur on the excited low‐spin surfaces in a TSR scenario.
ChemInform Abstract: Photoelectron Spectroscopy and ab initio Study of the Structure and Bonding of Al7N‐ and Al7N.
Authors: Averkiev Boris B. , Call Seth , Boldyrev Alexander I. , Wang Lei‐Ming , Huang Wei , Wang Lai‐Sheng
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sonochemical Synthesis and Luminescence Properties of Single‐Crystalline BaF2:Eu3+ Nanospheres.
Authors: Zhu Ling , Meng Jian , Cao Xueqiang
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reaction of α,β‐Unsaturated Ketones Using Cerium(IV) Sulfate Tetrahydrate in Acetic Acid.
Authors: Horiuchi C. Akira , et al. et al.
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: New Triazole and Triazolothiadiazine Derivatives as Possible Antimicrobial Agents.
Authors: Kaplancikli Zafer Asim , Turan‐Zitouni Guelhan , Oezdemir Ahmet , Revial Gilbert
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Thiol‐Catalyzed Stereoselective Transfer Hydroamination of Olefins with N‐Aminated Dihydropyridines.
Authors: Guin Joyram , Froehlich Roland , Studer Armido
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Nickel/BPh3‐Catalyzed Alkynylcyanation of Alkynes and 1,2‐Dienes: An Efficient Route to Highly Functionalized Conjugated Enynes.
Authors: Nakao Yoshiaki , Hirata Yasuhiro , Tanaka Masaaki , Hiyama Tamejiro
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Lewis Acid Promoted Tandem Intermolecular Diels—Alder/Intramolecular Allylation Reactions of Silyl‐Substituted 1,3‐Butadienes Leading to Multisubstituted 7‐Norbornenones and Related Polycyclic Compounds.
Authors: Li Dongzhen , Liu Guangzhen , Hu Qiaoshu , Wang Chao , Xi Zhenfeng
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Mild Electrochemical Deprotection of N‐Phenylsulfonyl N‐Substituted Amines Derived from (R)‐Phenylglycinol.
Authors: Coeffard Vincent , Thobie‐Gautier Christine , Beaudet Isabelle , Le Grognec Erwan , Quintard Jean‐Paul
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Lewis Acid Mediated Unprecedented Ring‐Opening Rearrangement of 2‐Aryl‐N‐tosylazetidines to Enantiopure (E)‐Allylamines.
Authors: Ghorai Manas K. , Kumar Amit , Das Kalpataru
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Facile Synthesis of Highly Functionalized Stable Ketenimines via a Three‐Component Reaction.
Authors: Alizadeh Abdolali , Rostamnia Sadegh
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Highly Chemoselective Metal‐Free Reduction of Tertiary Amides.
Authors: Barbe Guillaume , Charette Andre B.
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Lewis Acid Catalyzed Formation of Ugi Four‐Component Reaction Product from Passerini Three‐Component Reaction System Without an Added Amine.
Authors: Dai Wei‐Min , Li Huoming
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Substituted Allylic Sulfonamides from β‐Alkoxy Aziridines and Organolithium Reagents.
Authors: Moore Stephen P. , O'Brien Peter , Whitwood Adrian C. , Gilday John
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of S‐Aryl/Alkyl Thiolcarbonates from Disulfides and Chloroformates in the Presence of the Zn/AlCl3 System.
Authors: Movassagh Barahman , Tavoosi Maryam
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Rhodium‐Catalyzed Enantioselective [2 + 2 + 2] Cycloaddition of Diynes with Unfunctionalized Alkenes.
Authors: Shibata Takanori , Kawachi Ai , Ogawa Mika , Kuwata Yusuke , Tsuchikama Kyoji , Endo Kohei
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Pd on Surface‐Modified NiFe2O4 Nanoparticles: A Magnetically Recoverable Catalyst for Suzuki and Heck Reactions.
Authors: Baruwati Babita , Guin Debanjan , Manorama Sunkara V.
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Novel Synthesis of Highly Substituted But‐2‐enoic Acid Esters by the Reaction of DMAP—Methyl Phenylpropiolate Zwitterion and Diaryl 1,2‐Diones.
Authors: Pillai Abhilash N. , Suresh Eringathodi , Nair Vijay
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reactivity of Several Deactivated 3‐Aminobenzo[b]thiophenes in the Buchwald—Hartwig C—N Coupling. Scope and Limitations.
Authors: Queiroz Maria‐Joao R. P. , Calhelha Ricardo C. , Kirsch Gilbert
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Facile Synthesis of a “Ready to Use” Precursor of Porphobilinogen and Its Amino Acid Derivatives.
Authors: Soldermann‐Pissot Carole , Vallinayagam Ramakrishnan , Tzouros Manuel , Neier Reinhard
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Platinum‐Catalyzed Formation of Cyclic‐Ketone‐Fused Indoles from N‐(2‐Alkynylphenyl)lactams.
Authors: Li Guotao , Huang Xiaogen , Zhang Liming
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A One‐Pot, Ugi Four‐Component Synthesis of 2(3H)‐Oxazolone 4‐Carboxamides.
Authors: Garcia‐Valverde M. , Macho S. , Marcaccini S. , Rodriguez T. , Rojo J. , Torroba T.
Published: April 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.