bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic resonance imaging of the wrist ligaments
Authors: Connell David , Page Patrick , Wright Warwick , Hoy Greg 
Published: March 2003

SUMMARYThe advent of small arthroscopes has enabled the hand surgeon to visualize the ligaments of the wrist directly with resultant increased accuracy in diagnosing and treating pathology. Orthopaedists are now demanding a preoperative assessment and this, in turn, has necessitated that radiologists have a comprehensive understanding of wrist anatomy. High resolution MR imaging can identify the wrist ligaments reliably and provide information concerning their integrity. Interpretation is not straightforward; there is considerable anatomic variation, and there are perforations, defects and degenerative tears that can be troublesome in diagnosing injury. However, with experience and attention to anatomic detail, the radiologist can provide useful information regarding structural abnormalities. When injured, the ligaments of the wrist behave as other joint ligaments do. Findings following injury include discontinuity of normal striated bands, incomplete disruption, irregularities and alteration in normal signal. Fluid pooling around a ligament and concomitant bone injury are other clues to injury. The identification of such structural abnormalities may help to explain altered biomechanics and improve the management of patients following wrist injury.
Locally advanced cervix cancer: Chemotherapy prior to definitive surgery or radiotherapy. A single institutional experience
Authors: MacLeod Craig , O'Donnell Anne , Tattersall Martin HN , Dalrymple Chris , Firth Ian 
Published: March 2003

SUMMARYPrimary or neoadjuvant chemotherapy prior to definitive local therapy has potential advantages for locally advanced cervix cancer. It can downstage a cancer and allow definitive local therapy to be technically possible (surgery), or potentially more effective (radiotherapy). It can also eradicate subclinical systemic metastases. This report reviews a single institution’s experience of neoadjuvant chemotherapy prior to definitive local therapy for cervix cancer over a 13‐year period. One hundred and six patients were treated with this intent. The patients were analysed for their response to chemotherapy, treatment received, survival, relapse and toxicity. The chemotherapy was feasible and the majority of patients had a complete or partial response (58.5%). Eight patients did not proceed to local treatment. Forty‐six patients had definitive surgery and 52 had definitive radiotherapy. The 5‐year overall survival was 27% and the majority of patients died with disease. The first site of relapse was usually in the pelvis (46.2%). Late complications that required ongoing medical therapy (n = 6) or surgical intervention (n = 2) were recorded in eight patients (7.5%). On univariate analysis stage (P = 0.04), tumour size (P = 0.01), lymph node status (P = 0.003), response to chemotherapy (P = 0.045) and treatment (P = 0.003) were all significant predictors of survival. On multivariate analysis, tumour size (P < 0.0001) and nodal status (P = 0.02) were significant predictors of survival. Despite the impressive responses to chemotherapy of advanced cervix cancer, there is evidence from randomized trials that it does not improve or compromise survival prior to radiotherapy. As its role prior to surgery remains unclear, it should not be used in this setting outside a prospective randomized trial.
Gallium avid breast carcinoma
Authors: Chan Wai‐Ling , Wadhwa Surjit S , Carolan Martin G 
Published: March 2003

SUMMARYPrimary breast carcinomas are generally thallium (Tl‐201) avid but uncommonly accumulate gallium (GA‐67). Therefore, GA‐67 scans are not routinely performed in patients with suspected breast cancer. We report a rare case of a primary breast carcinoma with bone marrow metastases where the primary lesion was GA‐67 avid but did not accumulate Tl‐201. The case also illustrated an unusual presentation of aggressive metastatic breast adenocarcinoma with pancytopenia or bone marrow failure. The extensive bone marrow metastases of the primary breast carcinoma were evident on both the Tl‐201 and GA‐67 scans.
Can virtual simulation of breast tangential portals accurately predict lung and heart volumes?
Authors: Cooke Stacey , Rattray Greg 
Published: March 2003

SummaryA treatment portal or simulator image has traditionally been used to demonstrate the lung and heart coverage of the breast tangential portal. In many cases, these images were acquired as a planning session on the linear accelerator. The patients were also CT scanned to assess the lung/heart volume and to determine the surgical site depth for the electron‐boost energy. A study using 50 consecutive patients was performed comparing the digitally reconstructed radiograph (DRR) from the virtual simulation with treatment portal images. Modification to the patient's arm position is required when performing the planning CT scans due to the aperture size of the CT scanner. Virtual simulation was used to assess the potential variation of lung and heart measurements. The average difference in lung volume between the DRR and portal image was less than 2 mm, with a range of 0−5 mm. Arm position did not have a sig­nificant impact on field deviation; however, great care was taken to minimize any changes in arm position. The modification of the arm position for CT scanning did not lead to significant variations between the DRRs and portal images. The Advantage Sim software has proven capable of producing good quality DRR images, providing a realistic representation of the lung and heart volume included in the treatment portal.
EFFECT OF EXTRACELLULAR pH ON CONTRACTILE RESPONSES OF THE GUINEA‐PIG VAS DEFERENS
Authors: Nakanishi Hironori , Matsuoka Isao , Ono Tomoyuki , Kimura Junko 
Published: March 2003

1. Effects of changing the pH of the bathing solution (7.0, 7.4 and 7.8) on the contractile response of the guinea‐pig isolated vas deferens to ATP, noradrenaline (NA) and ATP in the presence of NA or electrical field stimulation (EFS) were investigated.2. Low pH tended to augment the phasic contractile response to ATP (0.01–1 mmol/L), while high pH significantly reduced the contractile response to ATP. In contrast, low pH depressed the tonic contractile response to NA (0.1–10 μmol/L), while high pH augmented the response to NA. The contractile response to 1 mmol/L ATP was markedly potentiated in the presence of 0.1–10 μmol/L NA. The potentiated contractile response to ATP in the presence of NA was unaffected by changes in pH.3. Electrical field stimulation produced a biphasic contractile response. Low pH enhanced the initial rapid phasic contractile response to EFS, while high pH depressed the response. In contrast, the second slow tonic contractile response to EFS was unaffected by changes in pH.4. These findings may indicate that the phasic contractile response to EFS is mainly caused by ATP while the tonic contractile response is a synergistic response to ATP and NA concomitantly released from sympathetic nerve terminals.
ADENOSINE AND PRECONDITIONING REVISITED
Authors: Miura Tetsuji , Tsuchida Akihito 
Published: March 2003

1. Myocardial tolerance against infarction is substantially increased by exposing myocytes to 3–10 min transient ischaemia. In this phenomenon, termed ‘preconditioning’, the adenosine receptor is one of the redundant triggers and the best characterized factor in the cardioprotective mechanism.2. An increase in interstitial adenosine during preconditioning is thought to be derived primarily from hydrolysis of 5′‐AMP in the myocyte by cytosolic 5′‐nucleotidase, although a contribution of ectosolic 5′‐nucleotidase remains controversial. Adenosine production during ischaemia is substantially suppressed in the preconditioned myocardium, probably due to a decrease in ATP utilization.3. The adenosine receptor needs to be activated not only at the time of preconditioning ischaemia, but also during ischaemic insult for the preconditioning to be cardioprotective. However, the extent of cardioprotection afforded by preconditioning is primarily determined by the interstitial adenosine level achieved during preconditioning ischaemia, not by the level during sustained ischaemia. These data suggest that a post‐receptor mechanism downstream of the adenosine receptor may be up‐regulated after preconditioning.4. Studies in vitro suggest that the subtypes of adenosine receptor relevant to preconditioning against infarction are A1 and A3, the activation of which appears to provide additive protection. The functional interrelationship between these subtypes in vivo remains unknown.5. An important step downstream of adenosine receptor activation is protein kinase C (PKC), which facilitates opening of ATP‐sensitive potassium (KATP) channels, probably leading to enhancement of myocardial tolerance. However, activation of other protein kinases, such as tyrosine kinase, may also be important in preconditioning, depending on the animal species and preconditioning protocols. The PKC isoform and location of KATP channels (i.e. sarcolemmal vs mitochondrial KATP) that induce anti‐infarct tolerance in myocytes remain to be identified.
CO‐OPERATION BETWEEN ENDOTHELIN AND NITRIC OXIDE IN PROMOTING ENDOTHELIAL CELL MIGRATION AND ANGIOGENESIS
Authors: Goligorsky Michael S , Budzikowski Adam S , Tsukahara Hirokazu , Noiri Eisei 
Published: March 2003

1. Among the diverse functions of endothelins (ET), their role in the remodelling of blood vessels remains poorly examined. In the present review, we summarize findings obtained in our laboratory and present four independent lines of evidence to support this novel function. We also demonstrate that the motogenic and angiogenic effects of ET are mediated via the ETB receptor and that the functional endothelial nitric oxide synthase (NOS) is requisite for this action.2. We demonstrated that ET stimulates transmigration of endothelial cells in a modified Boyden chamber and accelerates endothelial wound healing acting via ETB receptors.3. In genetically engineered Chinese hamster ovary cells expressing either ETB receptor or endothelial NOS or both, application of ET results in accelerated cell migration only when the receptor and the enzyme are coexpressed. Application of antisense oligonucleotides producing a specific knockdown of the endothelial NOS results in the loss of ET ability to stimulate endothelial cell migration in response to ET.4. Finally, using a novel model of in vivo angiogenesis, we were able to demonstrate that ET enhances formation of new vessels, but this effect requires functional endothelial NOS.5. The described phenomenon of NO production, serving as a prerequisite for endothelial cell locomotion in response to activation of ETB receptor may explain a host of pathophysiological observations on inadequate angiogenesis despite enhanced generation of ET‐1.6. Based on the contribution of endothelial cell migration to angiogenesis, these data may implicate insufficient NO production in pathological states (e.g. atherosclerosis, heart failure and hypertension) in the inappropriate response to angiogenic stimuli.
ADRENOCORTICOTROPHIC HORMONE‐INDUCED HYPERTENSION IN THE RAT: EFFECTS OF THE ENDOTHELIN ANTAGONIST BOSENTAN
Authors: Fraser Tafline B , Mangos George J , Turner Steven W , Whitworth Judith A 
Published: March 2003

1. The effects of the endothelin antagonist bosentan on adrenocorticotrophic hormone (ACTH)‐induced hypertension were examined in the conscious male Sprague‐Dawley rat.2. In order to confirm endothelin antagonism, 18 rats were randomly divided into two groups: receiving either (i) endothelin‐1 (0.125, 0.25, 0.5 and 1 nmol/kg, i.v.); or (ii) endothelin‐1 at these doses following bosentan (100 mg/kg gavage) and mean arterial pressure recorded (study A). Subsequently, 40 male rats (320±5 g) were randomly divided into four groups (n = 10): (i) Sham (0.9% saline, s.c.) + 5% acacia gum gavage; (ii) ACTH (500 μg/kg per day, s.c.) + 5% acacia gum gavage; (iii) Sham injection + bosentan (100 mg/kg per day) gavage; or (iv) ACTH + bosentan. Six control days (C1–C6) were followed by 11 treatment days (T0–T10). Systolic blood pressure, water intake, urine volume, food intake and bodyweight were measured every second day (study B).3. Bosentan significantly attenuated the endothelin‐1‐induced blood pressure rise at 0.125 nmol/kg (P < 0.05), but not at higher doses.4. Bosentan at a dose which attenuated endothelin‐1‐induced blood pressure increase had no effect on either blood pressure or metabolic parameters in ACTH‐treated rats.5. These results suggest that endothelin does not play a major role in ACTH‐induced hypertension.
EXPRESSION AND REGULATION OF THE SODIUM–CALCIUM EXCHANGER IN CARDIAC MICROVASCULAR ENDOTHELIAL CELLS
Authors: Kaye David M , Kelly Ralph A 
Published: March 2003

1. The sodium–calcium exchanger (NCX) plays an important role in Ca2+ homeostasis. In the heart, NCX participates in the control of contraction and relaxation and in large vessel endothelial cells some data suggest that NCX could influence nitric oxide (NO) generation. In this context, the cardiac microvasculature has received considerable attention as a mediator of myocardial performance, via the release of paracrine acting factors such as NO. Therefore, the aim of the current study was to characterize NCX expression and regulation in cardiac microvascular endothelial cells (CMEC). The NCX expression was also examined in neonatal ventricular cardiomyocytes where aspects of its function and regulation have been well characterized.2. The presence of functional NCX in CMEC was confirmed by the presence of a consistent rise in intracellular Ca2+ concentration ([Ca2+]i) in response to removal of extracellular Na+. Furthermore, NCX mRNA expression was readily detectable in CMEC.3. In order to examine the role of possible physiological regulators of NCX expression, the effect of intracellular Ca2+ loading, caused by 24 h exposure to 10 μmol/L ouabain, was investigated. In Ca2+‐loaded CMEC, there was a substantially greater rise in [Ca2+]i during exposure to Na+‐free buffer: 33±6 versus 124±25 nmol/L% (P < 0.05), consistent with increased protein expression. Consistent with these findings, northern blot analysis confirmed the presence of a two‐fold increase in NCX mRNA in these cells.4. These data indicate the presence of functional NCX in CMEC and identify [Ca2+]i as a potential physiological regulator of expression.
REDUCED DIETARY FAT INTAKE INCREASES PARASYMPATHETIC ACTIVITY IN HEALTHY PREMENOPAUSAL WOMEN
Authors: Pellizzer A‐M , Straznicky Ne , Lim S , Kamen Pw , Krum H 
Published: March 2003

1. Hypercholesterolaemia has been associated with decreased heart rate variability, a measure of cardiac parasympathetic activity. However, the effect of perturbation of the lipid profile on autonomic function has not been examined systematically.2. The effects of short‐term dietary lipid modification on autonomic function are studied in 25 normotensive, non‐smoking, premenopausal women with normal bodyweight. Subjects consumed either a low (L, 25%) or high fat (H, 40%) diet for 2 weeks in an open, randomized, cross‐over manner with a 2 week washout.3. Baroreflex sensitivity was determined by gating beat‐to‐beat heart period (RR) interval and continuous non‐invasive blood pressure recordings. Heart rate variability measures of cardiac parasympathetic nervous system activity were obtained in the time (standard deviation of RR intervals, root mean square of successive differences (rMSSD)) and frequency (high frequency power) domains. All assessments were made at the same timepoint in the menstrual cycle.4. Both low‐density lipoprotein–cholesterol and high‐density lipoprotein–cholesterol decreased significantly (P < 0.05) with increased dietary fat intake (H, 2.7±0.1 vs L, 2.2±0.1; H, 1.3±0.1 vs L, 1.1±0.1 mmol/L, respectively) as did mean arterial pressure (H, 78.1±1.5 vs L, 74.3±1.5 mmHg). Weight was unchanged by dietary lipid intake (H, 62.6±8.5 vs L, 62.3±8.3 kg, P = NS).5. There was a significant increase in rMSSD (H, 29.6±3.4 vs L, 38.8±6.4 msec, P < 0.05) and natural logarithm of high frequency power following low fat diet (H, 4.4±0.2 vs L, 4.8±0.3 msec2, P = 0.01). Baroreflex sensitivity also increased following the low fat diet (H, 13.91±2.2 vs L, 16.9±3.2 msec/mmHg, P = 0.23).6. Short‐term dietary lipid modification can significantly increase cardiac parasympathetic nervous system activity in healthy premenopausal women. These changes in autonomic status appear to be independent of changes in bodyweight and may be of clinical relevance considering the prognostic implications of heart rate variability in cardiovascular disease.
Brain Atrial Natriuretic Peptide Family Abolishes Cardiovascular Haemodynamic Alterations Caused By Hypertonic Saline In Rats
Authors: Sakamoto Masatoshi , Nishimura Masato , Takahashi Hakuo 
Published: March 2003

SUMMARY1. Regional haemodynamic alterations caused by hypertonic NaCl solution (Hi‐Salt; 10%, 10 μL) injected intracerebroventricularly (i.c.v.) were investigated by using radioactive microspheres in anaesthetized rats.2. Intracerebroventricular injections of Hi‐Salt increased regional vascular resistance of visceral organs, including the kidney, and elevated plasma levels of vasopressin.3. Intracerebroventricular pretreatment with TCV‐11974 (50 μg/10 μL/nat), an angiotensin AT1 receptor antagonist, attenuated the pressor response and vasopressin release to subsequently injected Hi‐Salt, but did not affect regional haemodynamic effects of i.c.v. Hi‐Salt on vascular resistance.4. In contrast, i.c.v. pretreatment with atrial natriuretic polypeptide (ANP) or type‐C natriuretic polypeptide (CNP) almost completely abolished the haemodynamic changes and vasopressin release caused by i.c.v. Hi‐Salt.5. The present findings indicate that a natriuretic family in the brain may be involved to a great degree in the central regulation of salt‐induced hypertension in rats, while brain angiotensin II is likely to participate only in vasopressin release.
Elevation Of Striatal Interleukin‐6 and Serum Corticosterone Contents In Mptp‐Treated Mice
Authors: Kaku Koichi , Shikimi Todahiro , Kamisaki Yoshinori , Shinozuka Kazumasa , Ishino Hiroshi , Okunishi Hideki , Takaori Shuji 
Published: March 2003

SUMMARY1. Changes in the content of striatal interleukins (IL‐1β and IL‐6) and serum corticosterone in relation to deterioration of the dopaminergic system induced by 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP; a dopaminergic neurotoxin; 20 mg/kg i.p., four administrations/12 h) in C57BL/6J mice were investigated.2. Striatal dopamine, IL‐1β, IL‐6 and serum corticosterone were measured on days 1 and 7 post‐MPTP.3. Dopamine depletion was more severe on day 7 than on day 1 post‐treatment.4. Increases in IL‐6 were observed on days 1 and 7 post‐MPTP. The increase in striatal IL‐6 content varied with the extent of dopamine depletion, although the IL‐1β concentration remained unchanged compared with control values on days 1 and 7 post‐treatment.5. Serum corticosterone was not different from control on day 1 post‐MPTP. However, marked increases in the serum corticosterone were observed on day 7 post‐treatment.6. These results suggest that changes in striatal IL‐6 and serum corticosterone are closely associated with the severity of MPTP‐induced dopaminergic degeneration.
EFFECTS OF CHELATION WITH EDTA AND VITAMIN B THERAPY ON NITRIC OXIDE‐RELATED ENDOTHELIAL VASODILATOR FUNCTION
Authors: Green Daniel J , O’Driscoll J Gerard , Maiorana Andrew , Scrimgeour Neil B , Weerasooriya Rukshen , Taylor Roger R 
Published: March 2003

SUMMARY1. ‘Chelation therapy’ with EDTA is being frequently used in patients with cardiovascular disease, despite limited objective evidence of effectiveness. Depressed nitric oxide (•NO)‐related endothelial function accompanies atherosclerosis, and even the vascular risk factors alone, and is improved by numerous interventions that also improve prognosis in vascular disease.2. The aim of the present study was to determine the influence of chelation therapy with EDTA alone and EDTA in combination with B vitamins on endothelial function.3. After a control series of saline infusions, we examined the effects of a series of EDTA infusions (1.5 g, 10 times over 6 weeks) in eight subjects with coronary artery disease. In addition, because EDTA is commonly supplemented by other components, particularly B group vitamins, we subsequently examined the effect of a similar series of vitamin‐supplemented EDTA infusions.4. Forearm blood flow (FBF) was assessed by plethysmography and graded intrabrachial infusions of the endothelium‐dependent vasodilator acetylcholine (ACh) and the endothelium‐ independent dilator sodium nitroprusside (SNP).5. There was no difference in vasodilation to either drug after EDTA alone compared with the control periods, but the response to ACh was augmented after combined therapy (P < 0.03,
ANOVA). The latter was accompanied by a small but consistent mean (±SEM) fall in plasma homocysteine of 1.6±0.5 μmol/L (P < 0.05).6. The selective increase in the vasodilator response to ACh after therapy with EDTA and several B group vitamins indicates that NO‐related endothelial function was improved. The absence of response to EDTA alone suggests that the supplementary vitamins were necessary for this benefit, which may have been related to the accompanying decrease in plasma homocysteine. These results, along with the current interest in the possible cardioprotective effects of vitamins and the increasing administration of ‘chelation therapy’, call for more definitive studies on these aspects of ‘alternative medicine’.
ENDOTHELIN REGULATION OF ADRENAL FUNCTION
Authors: Hinojosa‐Laborde Carmen , Lange Darrell L 
Published: March 2003

SUMMARY1. The goal of the present review is to recount the evidence that endothelin (ET) has a significant influence on the peripheral sympathetic nervous system by regulating the function of the adrenal medulla.2. The presence of an active ET system in the adrenal medulla has been clearly demonstrated. Endothelin protein, mRNA, binding sites and ET‐converting enzyme have been identified in adrenal tissue and medullary chromaffin cells, suggesting that this peptide may contribute to the regulation of adrenal medullary function.3. Studies investigating the function of ET in the adrenal gland have demonstrated that ET has a stimulatory effect on the adrenal medulla. Endothelin elicits an increase in catecholamine release from perfused intact adrenal glands as well as from cultured chromaffin cells. This effect has been shown to be mediated by ETA and ETB receptors.4. The mechanism by which ET causes an increase in catecholamine release from the adrenal medulla appears to be independent of cholinergic activation of chromaffin cells. Endothelin has been shown to act directly at chromaffin cells to increase intracellular calcium, which results in catecholamine release.5. Endothelin can indirectly affect catecholamine release by its effect on adrenal blood flow. Studies indicate that ET has both vasoconstrictor and vasodilator effects in the adrenal gland, which suggests a role for ET in the regulation of adrenal blood flow. Endothelin has also been proposed to participate in the selective contraction of the adrenomedullary veins, which enhances the discharge of catecholamines from the adrenal gland during activation.