bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serum Levels of Vascular Endothelial Growth Factor in Patients with Acute Myocardial Infarction Undergoing Reperfusion Therapy
Authors: Seko Yoshinori , Imai Yasushi , Suzuki Shin , Kamijukkoku Shuichi , Hayasaki Kazuya , Sakomura Yasuinari , Tobe Kazuyuki , Kadowaki Takashi , Maekawa Hiromitsu , Takahashi Naoyuki , Yazaki Yoshio 
Published: August 2015

1. Vascular endothelial growth factor, a potent angiogenic mitogen, is known to be induced in response to ischaemia as well as being secreted from tumour cells. However, the precise mechanism of vascular endothelial growth factor release in acute myocardial infarction and the effects of coronary reperfusion on the circulating levels of vascular endothelial growth factor are still unknown.
2. Nineteen patients with acute myocardial infarction who underwent early reperfusion therapy were studied. Serum levels of vascular endothelial growth factor before reperfusion were markedly increased as compared with those in 19 healthy control subjects [252.4 ± 158.1 pg/ml (mean ± SD) compared with undetectable]. After reperfusion, the serum vascular endothelial growth factor levels rapidly returned almost completely to the normal control range.
4. These data strongly suggest that the serum level of vascular endothelial growth factor is one of the most sensitive indicators of myocardial ischaemia.
Renal Afferents Responsive to Chemical and Mechanical Pelvic Stimuli in the Rabbit
Authors: Genovesi Simonetta , Pieruzzi Federico , Camisasca Paola , Golin Raffaello , Zanchetti Alberto , Stella Andrea 
Published: August 2015

1. Afferent nerve fibres sensitive to changes in the renal chemical environment have been found in the rat. To verify the existence of these fibres in the rabbit and their response pattern, afferent renal nerve activity was recorded during pelvic perfusions with NaCl solutions at different concentrations.
2. The experiments were carried out in 13 anaesthetized rabbits. Arterial pressure from a femoral catheter and afferent renal nerve activity from the distal stump of a cut renal nerve bundle were recorded. Three catheters were inserted into the renal pelvis to measure pelvic pressure, to allow pelvic perfusions at constant rates and to drain pelvic fluids.
3. After a control period, the pelvis was perfused with physiological saline (0.14 mol/l for 2 min), followed by one of a series of solutions containing increasing concentrations of NaCl (0.5, 0.75, 1.0 and 1.5 mol/l for 2 min). Pelvic perfusion was performed both at a low (0.2 ml/min) and a high (0.8 ml/min) flow rate for each solution tested.
4. In all animals arterial pressure was not modified during pelvic perfusions. Physiological saline did not change afferent renal nerve activity at the low perfusion rate, but it significantly increased afferent renal nerve activity and pelvic pressure at the high rate. Hypertonic NaCl solutions caused progressive increases in afferent renal nerve activity at both perfusion rates, and these effects were larger at the high perfusion rate.
5. These data demonstrate, in the rabbit, the existence of renal afferent nerves sensitive to discrete changes in pelvic ionic or osmotic concentration. The neural response is enhanced when renal mechano- and chemo-receptors are simultaneously activated.
Blood Pressure Parameters as Determinants of Small Artery Structure in Human Essential Hypertension
Authors: Cooper Anne , Heagerty Anthony M. 
Published: August 2015

1. Adaptive changes in small arteries may be more closely correlated with pulse pressure than with systolic, diastolic or mean blood pressures in human essential hypertension.
2. An analysis was performed on the structure of small arteries, age and blood pressure measurements obtained from 56 patients with untreated essential hypertension and 56 matched normotensive volunteers to examine the association between age, blood pressure and small artery structural parameters.
3. Essential hypertension was associated with an increase in media thickness and a decrease in lumen diameter, resulting in an increase in media/lumen ratio.
4. There was a significant correlation between age and media/lumen ratio in normotensive volunteers but not in patients with essential hypertension.
5. There was no correlation between any blood pressure and structural parameter in normotensive volunteers.
6. Both diastolic and mean blood pressures in essential hypertension correlated with media/lumen ratio (P &lt; 0.01); systolic blood pressure correlated less well (P &lt; 0.02). However, pulse pressure did not correlate with media/lumen ratio, suggesting that it is not a significant determinant of small artery structure in untreated essential hypertension.
Epithelial Migration in the Colon: Filling in the Gaps
Authors: Wilson Andrew J. , Gibson Peter R. 
Published: August 2015

1. The efficient repair of gastrointestinal mucosal injuries is essential in the preservation of the epithelial barrier to luminal antigens. Accumulated evidence suggests that epithelial migration plays a major part in this repair by rapidly resealing defects induced by both physiological and pathological insults, a process termed restitution.
2. This migration has been modelled in various ways, most commonly in mechanically wounded monolayers of cell lines or cells in primary culture, and in wounded human or animal tissue. Evidence from these models indicates that migration is a highly complex process, which is likely to involve the tightly controlled spatial and temporal interaction of multiple factors: (i) extracellular molecules such as soluble factors (e.g. growth factors, trefoil peptides, cytokines) and matrix components (e.g. collagen, laminin, fibronectin); (ii) signalling molecules activated by the interaction of these factors with cell surface receptors (e.g. protein kinases, phospholipases, low-molecular-weight GTPases); (iii) factors which regulate adhesion to other cells (e.g. E-cadherin) and to matrix components (e.g. integrins, hyaluronic acid receptors); (iv) factors which regulate detachment from the extracellular matrix (e.g. urokinase-type plasminogen activator, matrix metalloproteinases); and (iv) molecules which regulate cytoskeletal function (e.g. Rac), which allows the formation of specialized cellular processes termed lamellipodia.
3. The identification of physiologically relevant factors that stimulate epithelial cell migration, and a better understanding of their mechanism of action, may be beneficial in the development of novel therapeutic approaches in diseases such as inflammatory bowel disease through the pharmacological or dietary enhancement of this migration.
Dose-Related Effect of Intravenous l-Arginine on Muscular Blood Flow of the Calf in Patients with Peripheral Vascular Disease: A H215O Positron Emission Tomography Study
Authors: Schellong Sebastian M. , Böger Rainer H. , Burchert Wolfgang , Bode-Böger Stefanie M. , Galland Andrea , Frölich Jürgen C. , Hundeshagen Heinz , Alexander Klaus 
Published: August 2015

1. Endothelium-derived nitric oxide (NO) contributes to the regulation of vascular tone and blood pressure. Infusion of l-arginine produces systemic vasodilatation via stimulation of endogenous NO formation. Vasodilatation is accompanied by an increase in peripheral arterial blood flow. However, it is not known whether capillary nutritive blood flow increases as well. The time course and dose-response pattern of this effect remain to be elucidated.
2. Two groups of ten patients with peripheral vascular disease (PVD) received an intravenous infusion of 8 g or 30 g of l-arginine over a period of 40 min. Blood pressure and heart rate were monitored non-invasively. Muscular blood flow (MBF) of the calf was determined at 0, 20, 40, 60, 80 min by positron emission tomography with H215O as flow tracer. Plasma l-arginine and cyclic GMP (cGMP) levels were determined at the same time points.
3. l-arginine induced a dose-related decrease in blood pressure during the infusion period. MBF and plasma cGMP levels during and after the infusion of 8 g of l-arginine did not change significantly. In the patients receiving 30 g of l-arginine, MBF was enhanced significantly from 1.56 ± 0.14 to 2.09 ± 0.21 ml min−1 100 ml−1 at 40 min and 2.23 ± 0.15 ml min−1 100 ml−1 after 80 min (+43.0%). The increase in MBF was paralleled by an increase in plasma cGMP from 4789.8 ± 392.2 nmol/l at baseline to 9223.2 ± 1233.6 nmol/l at 40 min.
4. We conclude that intravenous l-arginine enhances nutritive capillary MBF in patients with PVD via the NO—cGMP pathway in a dose-related manner. This effect might be therapeutically beneficial in patients with PVD.
Functional Analysis of Histamine Release from Basophils and Mast Cells in Subjects with the Ile-181→Leu Variant of FcεRI-β
Authors: Airong LI , MacKay Graham A. , Hopkin Julian M. 
Published: August 2015

1. Atopy is a genetically heterogeneous disorder, but there is now strong evidence that one important locus is on chromosome 11q13. FcεRI-β at that location has been identified as a candidate gene and variants have been associated with atopy in population studies.
2. No information is available on the functional consequences of any of these variants, and defining this may prove difficult because of the complexity of the atopy phenotype and because FcεRIβ is expressed on a range of cells with different functions, including basophils, mast cells, eosinophils and antigen-presenting Langerhan's cells.
3. We have conducted a qualitative study of mast cell and basophil histamine release in nine atopic individuals with Ile-181→Leu mutation of FcεRIβ, and ten unrelated similarly atopic individuals without Ile-181→Leu mutation. There were non-significant trends for Ile-181→Leu-positive atopic subjects to produce wheal responses at lower allergen challenge in skin prick tests, and to release more histamine from basophils following in vitro allergen challenge.
4. The data do not provide decisive evidence of functional differences between atopic subjects with Ile-181→Leu and other atopic individuals; more discriminating functional experiments are required.
Age- and Gender-Related Changes in Endothelin and Catecholamine Release, and in Autonomic Balance in Response to Head-Up Tilt
Authors: White Michel , Courtemanche Marc , Stewart Duncan J. , Talajic Mario , Mikes Ethel , Cernacek Peter , Vantrimpont Pascal , Leclerc Diane , Bussières Lizanne , Rouleau Jean L. 
Published: August 2015

1. There is an increase in circulating levels of vasoconstrictive hormones and an alteration in baroreceptor responsiveness with aging. The role of changes in endothelium-dependent and -independent vasoconstrictive hormones in relation to age and gender, with simultaneous assessment of autonomic balance in response to head-up tilt, has been incompletely studied.
2. Sixteen young [25 ± 3 years (mean ± SEM)] and 16 older normal volunteers (68 ± 7 years) underwent a 30 min head-up tilt test at 60°. Haemodynamics were measured every 5 min and blood samples for neurohormone measurement were drawn at baseline, 5, 10, 15 and 30 min into the test. Heart rate variability was analysed in 5 min segments at the baseline, and during the test. The younger subjects exhibited a greater increase in heart rate and diastolic blood pressure, despite lower absolute levels of noradrenaline (norepinephrine) and endothelin-1. Analysis of heart rate variability yielded a decrease in both high- and low-frequency bands in the aged; power at low-frequency decreased only in the young subjects. The age-related differences in blood pressure and noradrenaline levels were markedly attenuated in the female subjects. In addition, endothelin-1 levels and power spectral measurements at low frequency were the lowest in younger females throughout the tilt.
3. Despite attenuated cardiovascular response to tilt, both systemic adrenergic ‘drive’ and endothelin-1 levels increase in parallel with aging. Thus, endothelium-dependent and -independent vasoconstrictive hormone levels increase with age in the resting state and in response to neurohumoral stimulation in humans.
Spontaneous and Induced Minisatellite Instability in the Human Genome
Authors: Jeffreys Alec J. 
Published: August 2015

1. Minisatellites, originally developed for forensic DNA fingerprinting and profiling, have also provided extremely informative systems for analysing processes of tandem repeat DNA turnover in the human genome.
2. Minisatellite instability involves distinct mutation processes in somatic and germline cells. In sperm, tandem repeat instability most likely arises at meiosis as a by-product of high-frequency meiotic recombination events occurring in and near minisatellites. Instability is not an intrinsic property of minisatellite repeat DNA, but instead appears to be controlled by flanking recombination initiation elements.
3. Minisatellites not only show high-frequency spontaneous mutation in the germline, but also appear to be very sensitive to mutation induction by ionizing radiation, both in experimentally irradiated mice and in human populations exposed following the Chernobyl disaster; the mechanisms of mutation induction by radiation remain enigmatic.
Activity of Erythrocyte Sodium-Hydrogen Exchange in Normal Pregnancy
Authors: Matteucci Elena , Giampietro Ottavio 
Published: August 2015

1. Pregnancy is associated with a 30–50% rise in cardiac output and a 50% increase in blood volume. The contribution of changes in the activity of primary and secondary active transporters to these haemodynamic adaptations remains unknown. For the first time, we measured sodium—hydrogen exchange activity over the course of normal pregnancy.
2. Eighteen healthy pregnant women were studied at 14, 24 and 33 weeks of gestation and compared with 18 non-pregnant healthy women. None of the pregnancies was complicated by hypertension. At each antenatal visit, body weight and blood pressure were recorded, blood and 24 h-urine samples were taken to control renal function and metabolic equilibrium, maternal glucose tolerance was evaluated by oral glucose test and glycated haemoglobin testing, and erythrocyte sodium-hydrogen antiport was also measured.
3. Erythrocyte antiport activity values were 10.0 ± 3.0, 9.6 ± 2.9 and 8.4 ± 3.5 mmol h−1 (litre of cells)−1 in the three gestational trimesters respectively, significantly higher at each trimester than in control women [6.8 ± 2.5 mmol h−1 (litre of cells)−1]. The clearances of urea and creatinine were constantly elevated in pregnant women; at each trimester their serum concentrations were lower than in non-pregnant women. Serum potassium significantly decreased during pregnancy. Serum total cholesterol and triacylglycerol levels, already above the normal range from the first trimester, further increased until the third trimester. The area under the glycaemic curve became larger during pregnancy, and the area under the insulinaemic curve increased to a lesser extent. There was a significant association between antiport activity and serum triacylglycerol levels.
4. The observed hyperactivity of the transporter, peaking at the fourteenth week of gestation, may be a contributing factor to the haemodynamic adjustments attending upon normal pregnancy.
Time-Course of Iron Overload and Biochemical, Histopathological and Ultrastructural Evidence of Pancreatic Damage in Hypotransferrinaemic Mice
Authors: Simpson Robert J. , Deenmamode Jean , McKie Andrew T. , Raja Kishor B. , Salisbury Jonathan R. , Iancu Theodore C. , Peters Timothy J. 
Published: August 2015

1. The time course of iron overload of the pancreas in hypotransferrinaemic mice maintained on a standard rodent diet was compared with biochemical and histological markers of tissue damage.
2. Pancreatic iron levels increased linearly from weaning till 9 months of age [73.3 nmol/mg of tissue (SEM 9.9; n = 5) compared with 0.9 nmol/mg of tissue (SEM 0.1; n = 4) in age-matched controls] then decreased linearly till at least 18 months of age.
3. Investigation of tissue distribution of newly absorbed radioiron suggested that significant redistribution of iron from liver to pancreas (rather than direct dietary iron sources) must be invoked to explain the rate of pancreatic iron loading in hypotransferrinaemic mice.
4. Pancreatic epithelial cells first showed altered morphology at 9 months of age. At 12 months of age, the pancreatic epithelium had developed a micronodular appearance, with large numbers of acini replaced by atrophic, degenerated acinar cells. Increased collagen fibre deposition was evident by trichrome staining and by electron microscopy. Biochemical markers of pancreatitis (serum lipase, tissue pancreatitis-associated protein mRNA) were elevated before 9 months of age, whereas the levels of pancreatic amylase mRNA declined from 9 months of age.
5. The data suggest that iron loading of hypotransferrinaemic mouse pancreas proceeds up to a threshold level at 9 months of age followed by a progressive atrophy of secretory epithelium. The hypotransferrinaemic mouse pancreas is a useful model system for investigation of parenchymal cell damage by iron.
Xenotransplantation: Immune Barriers beyond Hyperacute Rejection
Authors: Dorling Anthony , Lechler Robert I. 
Published: August 2015

1. The use of organs from animal donors (xenotransplantation) is a potential solution to the chronic shortage of allogeneic organs and currently the pig is thought to be the most suitable donor for man. However, porcine organs are rejected rapidly by a vascular process called hyperacute rejection which has so far prevented clinical xenotransplantation. Although it is likely that this barrier will be overcome in the near future by the application of novel strategies, probably involving the use of organs from transgenic pigs, data from animal models indicate that multiple other immune mechanisms will contribute to the rejection of xenografts.
2. We have described two aspects of these immune mechanisms. First, the phenomenon of ‘accommodation’, whereby xenografts acquire in vivo resistance to vascular rejection, has been explored in an in vitro model utilizing immortalized porcine endothelial cells. The results indicate that human anti-pig antibodies induce a concentration-dependent and time-dependent change in porcine endothelial cells compatible with the development of accommodation.
3. Secondly, the in vitro human anti-porcine T-cell response has been documented in detail, with particular emphasis on quantitative and qualitative comparisons with the in vitro T-cell alloresponse. The results of this work, which indicate that the response to porcine xenografts is likely to be significantly stronger than that against allografts, have important implications for the level of conventional immunosuppression that may be necessary to prevent xenograft rejection, and provide an important basis for the development of strategies to promote xenograft-specific immunosuppression and tolerance.
Vasoconstrictor Sensitivity to Noradrenaline and NG-monomethyl-l-arginine in Men and Women
Authors: Kneale Barry J. , Chowienczyk Philip J. , Cockcroft John R. , Coltart D. John , Ritter James M. 
Published: August 2015

1. Nitric oxide has potential anti-atherogenic actions as well as regulating vascular tone. Animal studies suggest that there are sex differences in basal nitric oxide biosynthesis, but it is not known whether such differences exist between men and women.
2. We have investigated this question by measuring forearm blood flow responses, using venous occlusion plethysmography, to brachial artery infusion of NG-monomethyl-l-arginine (an inhibitor of NO biosynthesis) and noradrenaline in 40 healthy subjects (20 men and 20 premenopausal women). Mean arterial blood pressure was 89 ± 10 mmHg (mean ± SD) in men and 87 ± 9 mmHg in women, and mean total cholesterol was 4.25 ± 0.99 mmol/l (mean ± SD) and 4.26 ± 0.80 mmol/l respectively.
3. In men, vasoconstrictor responses to NG-monomethyl-l-arginine, 1–4 μmol/min (15–28% mean reduction in blood flow), were consistently less than responses to noradrenaline, 60–240 pmol/min (26–37%), whereas in women, vasoconstrictor responses to NG-monomethyl-l-arginine (19–30%) were consistently greater than those to noradrenaline(11–17%). The sex difference in relative sensitivity to vasoconstrictors was significant (P &lt; 0.001).
4. Our findings are consistent with either greater sensitivity to noradrenaline in men compared with premenopausal women, or a greater basal nitric oxide biosynthesis in premenopausal women compared with men.
Effect of Acute Hyperglycaemia on Basal and Fat-Induced Exocrine Pancreatic Secretion in Humans
Authors: Lam W. F. , Muller E. S. M. , Souverijn J. H. M. , Lamers C. B. H. W. , Masclee A. A. M. 
Published: August 2015

1. We have investigated the effect of acute hyperglycaemia on pancreatico-biliary secretion in healthy subjects. Duodenal outputs of trypsin, lipase, amylase, bicarbonate and bilirubin were measured for 90 min under basal conditions and for 90 min in response to intrajejunal fat administration (1 g/h) on 2 separate days: during normoglycaemia (blood glucose 5 mmol/l) and during acute hyperglycaemia aimed at 15 mmol/l. Plasma cholecystokinin levels, as the major hormonal stimulus of pancreatic and biliary secretion, and plasma pancreatic polypeptide levels, as an indirect measure of vagal-cholinergic tone, were determined at regular intervals.
2. In the basal period pancreatico-biliary secretion was significantly (P &lt; 0.05) reduced during hyperglycaemia compared with normoglycaemia. During normoglycaemia and hyperglycaemia intrajejunal fat significantly (P &lt; 0.05) stimulated pancreaticobiliary secretion. However, during hyperglycaemia, fat-stimulated 90 min pancreatico-biliary secretion was significantly (P &lt; 0.05) reduced compared with normoglycaemia: trypsin (23 ± 7 units versus 66 ± 20 units), lipase (36 ± 8 k-units versus 74 ± 18 k-units), amylase (8 ± 2 k-units versus 18 ± 5 k-units) and bilirubin (32 ± 8 μmol versus 71 ± 14 μmol). Plasma cholecystokinin levels increased significantly (P &lt; 0.05) during fat administration and were not different between the two experiments. Plasma pancreatic polypeptide levels were significantly (P &lt; 0.05) reduced during hyperglycaemia both in the basal period and during intrajejunal fat administration.
3. It is concluded that basal and fat-stimulated pancreatico-biliary secretion are significantly reduced during acute hyperglycaemia. Acute hyperglycaemia does not affect intrajejunal fat-stimulated cholecystokinin secretion. Acute hyperglycaemia inhibits basal and stimulated pancreatic polypeptide secretion suggesting vagal-cholinergic inhibition of pancreatico-biliary secretion during hyperglycaemia.
Pcr Detection of the Human Papillomavirus: Improved DNA Recovery from Frozen Biopsies
Authors: Mota Fernando F. , Kanan Joao H. 
Published: August 2015

1. One of the main obstacles to the reliable detection of human papillomavirus in cervical intraepithelial neoplasia is that a minute quantity of infected tissue is often all that is available.
2. In this work, proteinase K-phenol-chloroform-treated sections of frozen cervical biopsies were split in two. Half of the material was precipitated by ethanol in the presence of glycogen, and in the remaining half glycogen was absent.
3. On average a 15-fold increase in total DNA yield was obtained with glycogen. As a result, in 63 cases analysed by PCR for human papillomavirus type 16, we were able to detect nearly 20% more positive samples when glycogen was used.
4. The implications of the improved accuracy of diagnosis are that women requiring a closer follow-up can be identified, and conversely rescreening intervals can be extended for those testing negative for oncogenic human papillomavirus types with more confidence than in the past.