bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antioxidant and Oxidative Stress Indices in Dialysis-Dependent Acute Renal Failure
Authors: Balakrishnan Vaidyanathapuram S. , Blumberg Jeffrey , Pereira Brian J.G. , Jaber Bertrand L. 
Published: June 2003

<i>Background:</i> Experimental animal models and in vitro studies have established a role for reactive oxygen species and the therapeutic potential for free radical scavengers in acute renal failure (ARF). Little is known of the effects of hemodialysis and other clinical variables on antioxidant defenses and oxidative stress among patients with ARF. <i>Methods:</i> We examined antioxidant defenses and oxidative stress status in 24 patients with ARF requiring hemodialysis (HD). Blood samples were drawn prior to the first dialysis session (baseline), as well as before and after the third and sixth dialysis sessions. At each time point, the following parameters were measured: plasma α-tocopherol (vitamin E), plasma glutathione peroxidase (GSH-Px), serum total oxygen radical absorbance capacity (ORAC), plasma thiobarbituric acid reactive substances (TBARS), plasma tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10). Multivariate linear regression analyses were performed to examine clinical/laboratory variables associated with antioxidant/oxidative stress indices. The changes in antioxidant/oxidative stress indices over time after initiation of hemodialysis was evaluated in a subgroup of patients (n = 11) who completed six dialysis sessions. Intradialytic changes in antioxidant/oxidative stress indices and the differential impact of cellulose acetate vs. polysulfone dialyzers were also evaluated. <i>Results:</i> Factors associated with α-tocopherol level were serum albumin (301 µg/dl ↑ for each 1 g/dl ↑ in albumin) and ORAC (188 µg/dl ↑ for each 1,000 µmol Trolox Eq/l ↑ in ORAC). Age was independently associated with plasma GSH-Px levels (55 U/l ⇓ for each 10-year age ↑ ). Factors associated with ORAC were α-tocopherol (85 µmol Trolox Eq/l ↑ for each 100 µg/dl ↑ in α-tocopherol) and total bilirubin (30 µmol Trolox Eq/l ⇓ for each 1 mg/dl ↑ in total bilirubin). Total bilirubin was independently associated with TBARS (0.2 µ<i>M </i>↑ for each 1 mg/dl ↑ in total bilirubin). GSH-Px and ORAC levels declined over time between baseline and the sixth dialysis session (p < 0.05 for both). Finally, there was a significant intradialytic decline in ORAC levels, which appeared to be more pronounced with use of cellulose acetate compared with polysulfone dialyzer membranes (p < 0.05). <i>Conclusions:</i> These observations indicate that antioxidant and oxidative stress indices in ARF patients are associated with several clinical and laboratory variables as well as the dialysis procedure. Further studies are needed to investigate the therapeutic role of anti-oxidant therapy in these patients.
Attenuation of Axon Reflexes to Compound 48/80 after Repeated Iontophoresis of Compound 48/80 in Skin of the Human Forearm
Authors: Drummond P.D. 
Published: June 2003

The aim of this study was to determine whether the iontophoretic administration of the mast cell degranulator compound 48/80 influences axon reflex vasodilatation in the skin of the human forearm. In stage 1, compound 48/80 was administered by iontophoresis to a circular site in the forearm of 9 healthy men and 8 healthy women on four occasions spread over 24 h. Two control sites were also prepared by passing the iontophoretic current through 0.9% saline. Large wheals initially developed at the compound 48/80 site in 8 of the males and in 2 of the females, but wheals were minimal in all subjects by the fourth administration. In stage 2, compound 48/80 iontophoresis provoked substantial flaring at the first control site, whereas saline iontophoresis induced only minor flaring at the second control site, indicating that compound 48/80 induced axon reflex vasodilatation. However, prior treatment with compound 48/80 inhibited flaring to compound 48/80 in subjects who initially developed wheals, consistent with mast cell degranulation. In stage 3, flaring after iontophoresis of histamine was investigated at the site of compound 48/80 pretreatment and at the second control site in 12 subjects. Flaring was impaired only slightly in 6 subjects who initially developed wheals to compound 48/80. The persistence of flaring indicates that repeated administrations of compound 48/80 did not abolish neurogenic inflammation. Transcutaneous iontophoresis of compound 48/80 may be an attractive alternative to intradermal injection in studies that aim at clarifying the function of mast cells in healthy and diseased skin.
Morphological Studies of Prolactin-Secreting Cells in Estrogen Receptor α and Estrogen Receptor β Knockout Mice
Authors: Pelletier Georges , Li Songyun , Phaneuf Daniel , Martel Céline , Labrie Fernand 
Published: June 2003

Estrogens play a major role in the regulation of prolactin (PRL) secretion through activation of pituitary and hypothalamic estrogen receptors (ERs). In order to evaluate the relative role of ERα and ERβ in the control of PRL density in the pituitary gland, we performed immunocytochemical localization of PRL and ERs in pituitaries of wild-type (WT), ERα knockout (KO) and ERβKO mice. In WT and ERβKO anterior pituitaries, the vast majority of secretory cells contained ERα immunoreactivity, while no ERα immunostaining could be found in ERαKO pituitaries. No ERβ immunoreactivity could be detected in pituitaries of WT, ERαKO or ERβKO mice. At the light microscopic level, a large number of cells staining for PRL were present in pituitaries of female WT, while in female ERαKO pituitaries, the density of PRL cells was much lower. In WT male pituitaries, the density of PRL cells was lower than observed in female WT, while PRL staining was markedly decreased in male ERαKO as compared to male WT. In ERβKO mice of both sexes, the results were identical to those observed in WT animals. At the electron microscopic level, in WT mice of both sexes, type 1 PRL cells exhibited a well-developed Golgi apparatus and a large number of strongly stained large mature and immature secretory granules. Type 2 PRL cells were also present in the pituitary. Type 2 PRL cells contain small poorly labelled granules. In ERαKO mice of both sexes, type 1 PRL cells were atrophied with poorly developed Golgi apparatus, and no type 2 PRL cells could be observed. In ERαKO pituitaries, typical gonadectomy cells were found. No ultrastructural changes were observed in PRL cells of ERβKO mice. The present data strongly suggest that the positive regulation of PRL expression at the pituitary level by estrogens is mediated by ERα and does not involve ERβ activation.
Systematic Usability Evaluation and Design Issues for Collaborative Virtual Environments
Authors: Tromp Jolanda G. , Steed Anthony , Wilson John R. 
Published: June 2003

This paper presents results of the longitudinal usability and network trials that took place throughout the COVEN (COllaborative Virtual ENvironments) Project. To address the lack of understanding about usability design and evaluation for collaborative virtual environments (CVEs), a deductive analysis was used to systematically identify areas of inquiry. We present a summary of the analysis and the resulting framework through which various complementary methods were utilized during our studies. The objective of these studies was to gain a better understanding about design, usability, and utility for CVEs in a multidisciplinary setting. During the studies, which span four years, we undertook longitudinal studies of user behavior and computational demands during network trials, usability inspections of each iteration of the project demonstrators, consumer evaluations to assess social acceptability and utility of our demonstrators, and continuous preparations of design guidelines for future developers of CVEs. In this paper, we discuss the need for such activities, give an overview of our development of methods and adaptation of existing methods, give a number of explanatory examples, and review the future requirements in this area.
Virtual Reality Serves as a Support Technology in Cardiopulmonary Exercise Testing
Authors: Chuang Tien-Yow , Chen Chih-Hung , Chang Hwa-Ann , Lee Hui-Chen , Chou Cheng-Lian , Doong Ji-Liang 
Published: June 2003

The purpose of this study was to develop a virtual cycling system and examine the influence of virtual reality (VR) on test performance during clinical exercise testing. We aimed to compare the physiological responses of the cardiovascular and ventilatory systems during incremental exercise testing with or without VR, and to measure VR effects on the ratings of perceived exertion (RPE) and cycling duration throughout the test. Twelve healthy senior citizens (ten men and two women) with a mean age of 74.5-4.7 years participated in the study. The codes of behavior for this study included a maximum graded exercise tolerance test, a submaximal endurance VR exercise, and a submaximal endurance non-VR exercise. A friction-braked cycle ergometer was used to conduct the exercise tests. For the subject's movement speed to create an appropriate environment flow on the display screen, the bike was connected to a personal computer. The cardiorespiratory and hemodynamic parameters were evaluated at both peak and submaximal exertion. The results show that the VR versus non-VR programs did not differ on submaximal and peak exercise responses during the cycling test. However, significant differences were observed between the mean values for cycling duration, distance, and energy consumption. The difference between RPE curves for VR and non-VR protocols revealed promising results within 45 min. of cycling (Breslow test, p = .06); however, no statistical significance was achieved at the test termination (log rank test, p =.17). In conclusion, this study found that the maintenance of endurance, the increase in target intensity, and total energy consumption in exercise programs may be assisted by introducing VR technology. In addition, the activities taking place in virtual environments can be performed in complete safety.
Expression of cVg1 mRNA during chicken embryonic development
Authors: Somi Semir , Houweling Arjan C. , Buffing Anita A.M. , Moorman Antoon F.M. , Van Den Hoff Maurice J.B. 
Published: June 2003

AbstractUsing degenerated PCR‐primers to identify known and novel BMPs that are expressed in the developing chicken heart, we identified not only BMP2, ‐4, and ‐7 mRNA, but also the TGFβ superfamily member cVg1. The expression pattern of cVg1 mRNA was determined during chicken development from HH4 to HH44. In early developmental stages, cVg1 mRNA is expressed in the primitive streak, paraxial mesoderm, developing somites, and developing neural tube. Subsequently, cVg1 mRNA is expressed in the developing central and peripheral nervous system, retina, auditory vesicle, notochord, lung alveoli, and olfactory mucosa. In the heart, cVg1 is initially expressed through the linear heart tube, but becomes restricted to the forming chamber myocardium, in an expression domain similar to that of atrial natriuretic factor (ANF) mRNA. Anat Rec Part A 273A:603–608, 2003. © 2003 Wiley‐Liss, Inc.
Ontogenetic and regional morphologic variations in the turkey ulna diaphysis: Implications for functional adaptation of cortical bone
Authors: Skedros John G. , Hunt Kenneth J. , Hughes Paul E. , Winet Howard 
Published: June 2003

AbstractThis study examines relationships between bone morphology and mechanically mediated strain/fluid‐flow patterns in an avian species. Using mid‐diaphyseal transverse sections of domestic turkey ulnae (from 11 subadults and 11 adults), we quantified developmental changes in predominant collagen fiber orientation (CFO), mineral content (%ash), and microstructure in cortical octants or quadrants (i.e., %ash). Geometric parameters were examined using whole mid‐diaphyseal cross‐sections. The ulna undergoes habitual bending and torsion, and demonstrates nonuniform matrix fluid‐flow patterns, and high circumferential strain gradients along the neutral axis (cranial‐caudal) region at mid‐diaphysis. The current results showed significant porosity differences: 1) greater osteocyte lacuna densities (N.Lac/Ar) (i.e., “non‐vascular porosity”) in the caudal and cranial cortices in both groups, 2) greater N.Lac/Ar in the pericortex vs. endocortex in mature bones, and 3) greater nonlacunar porosity (i.e., “vascular porosity”) in the endocortex vs. pericortex in mature bones. Vascular and nonvascular porosities were not correlated. There were no secondary osteons in subadults. In adults, the highest secondary osteon population densities and lowest %ash occurred in the ventral‐caudal, caudal, and cranial cortices, where shear strains, circumferential strain gradients, and fluid displacements are highest. Changes in thickness of the caudal cortex explained the largest proportion of the age‐related increase in cranial‐caudal breadth; the thickness of other cortices (dorsal, ventral, and cranial) exhibited smaller changes. Only subadult bones exhibited CFO patterns corresponding to habitual tension (ventral) and compression (dorsal). These CFO variations may be adaptations for differential mechanical requirements in “strain‐mode‐specific” loading. The more uniform oblique‐to‐transverse CFO patterns in adult bones may represent adaptations for shear strains produced by torsional loading, which is presumably more prevalent in adults. The micro‐ and ultrastructural heterogeneities may influence strain and fluid‐flow dynamics, which are considered proximate signals in bone adaptation. Anat Rec Part A 273A:609–629, 2003. © 2003 Wiley‐Liss, Inc.
Anatomy and motor pathways of the electric organ of skates
Authors: Koester David M. 
Published: June 2003

AbstractThe electric organ of skates is a paired structure within the tail consisting of two longitudinal columns of electrocytes contained within the lateral musculature on each side of the vertebral column. The electrocytes develop from hypaxial skeletal muscle fibers, and, depending upon the species, are generally classified as either cup‐shaped or disc‐shaped. The disc‐shaped electrocytes are considered to be the more derived type. Regardless of the morphology of the electrocyte, the electric organ discharge of all skates is characterized as a weak asynchronous and long‐lasting signal. Although recent behavioral investigations have revealed a communicative function for the electric organ, details as to which specific behaviors utilize this motor system remain uncertain. The electric organ is innervated by segmental motor nerves that branch from the ventral root of caudal spinal nerves at all levels of the electric organ. The cells of origin of the electromotor nerves, or electromotoneurons (EMNs), are large multipolar neurons with extensive dendrites located within the ventral gray matter of the spinal cord. The EMNs are uniformly distributed among the somatic motoneurons at levels corresponding to the rostrocaudal extent of the electric organ, and therefore do not form a discrete nucleus. The medullary command nucleus is comprised of neurons located within the nucleus raphe magnus, and forms a descending spinal pathway to the EMNs. Anat Rec Part A 273A:648–662, 2003. © 2003 Wiley‐Liss, Inc.
Portal vein resection and reconstruction prior to hepatic dissection during right hepatectomy and caudate lobectomy for hepatobiliary cancer
Authors: Kondo S , Katoh H , Hirano S , Ambo Y , Tanaka E , Okushiba S 
Published: June 2003

Abstract

Background
Hepatobiliary cancer invading the hilar bile duct often involves the portal bifurcation. Portal vein resection and reconstruction is usually performed after completion of the hepatectomy. This retrospective study assessed the safety and usefulness of portal vein reconstruction prior to hepatic dissection in right hepatectomy and caudate lobectomy plus biliary reconstruction, one of the common procedures for radical resection.

Methods
Clinical characteristics and perioperative results were compared in patients who underwent right hepatectomy and caudate lobectomy plus biliary reconstruction with (ten patients) and without (11 patients) portal reconstruction from September 1998 to March 2002.

Results
All ten portal vein reconstructions were completed successfully before hepatic dissection; the portal cross-clamp time ranged from 15 to 41 (median 22) min. Blood loss, blood transfusion during the operation, postoperative liver function, morbidity and length of hospital stay were similar in the two groups. No patient suffered postoperative hepatic failure or death.

Conclusion
This study demonstrates that portal vein reconstruction does not increase the morbidity or mortality associated with right hepatectomy and caudate lobectomy with biliary reconstruction. This approach facilitates portal vein reconstruction for no-touch resection of hepatobiliary cancer invading the hilar bile duct.
Temporary closure of open abdominal wounds by the modified sandwich–vacuum pack technique
Authors: Navsaria P H , Bunting M , Omoshoro-Jones J , Nicol A J , Kahn D 
Published: June 2003

Abstract

Background
A 5-year experience with the modified sandwich–vacuum pack technique, using an opened 3-litre urological irrigation bag and continuous high-pressure suction, for temporary abdominal wall closure is presented.

Methods
The records of all patients who underwent temporary abdominal wall closure using this method from January 1996 to December 2000 were examined.

Results
The modified sandwich–vacuum pack was used 139 times in 55 patients. Forty patients sustained penetrating trauma while 15 patients sustained blunt trauma. The mean Injury Severity Score was 19 (range 9–34). Intra-abdominal sepsis (51 per cent) was the commonest indication, followed by visceral oedema (18 per cent), abdominal compartment syndrome (16 per cent), intra-abdominal packing (11 per cent) and abdominal wall defects (4 per cent). The overall mortality rate was 45 per cent. Three patients (5 per cent) developed enterocutaneous fistula. Of the 30 survivors, 16 patients underwent primary fascial closure.

Conclusion
The modified sandwich–vacuum pack technique of temporary abdominal wall closure is easy and rapid, cost effective and provides an effective means of containing abdominal wall contents.
Randomized clinical trial of the effect of interferon α on survival in patients with disseminated midgut carcinoid tumours
Authors: Kölby L , Persson G , Franzén S , Ahrén B 
Published: June 2003

AbstractBackgroundMidgut carcinoid tumours often present with widespread disease making curative surgery impossible. Medical treatment therefore plays a major role in the treatment of these patients.MethodsIn this prospective randomized study, the effect of interferon (IFN) α on survival and risk of tumour progression was evaluated in 68 patients with midgut carcinoid tumours metastatic to the liver. All patients had undergone primary surgical treatment and hepatic arterial embolization of liver metastases before randomization. Patients were randomized to treatment with either octreotide alone (n = 35) or octreotide in combination with IFN-α (n = 33).ResultsForty-one of the 68 patients died during a follow-up period of 33–120 months, equivalent to a 5-year survival rate of 46·5 per cent. There was no significant difference in survival between patients treated with octreotide alone (5-year survival rate 36·6 per cent) and those given octreotide in combination with IFN-α (56·8 per cent). However, patients treated with IFN-α had a significantly reduced risk of tumour progression during follow-up (P = 0·008).ConclusionAddition of IFN-α to octreotide may retard tumour growth in patients with midgut carcinoid tumours.
Image-directed parathyroidectomy under local anaesthesia in the elderly
Authors: Biertho L , Chu C , Inabnet W B 
Published: June 2003

Abstract

Background
Surgical morbidity and mortality rates are increased in elderly patients. The aim of this study was to evaluate the outcome of targeted parathyroid operations in patients over the age of 70 years.

Methods
Forty patients aged over 70 years underwent targeted parathyroidectomy for primary hyperparathyroidism (HPT). Data were collected prospectively and reviewed retrospectively.

Results
There were 33 women and seven men with a mean age of 78 (range 70–92) years, all of whom had symptoms attributable to HPT. A solitary parathyroid adenoma was detected by ultrasonography and/or sestamibi scintigraphy before operation in all patients. Six patients had a history of neck surgery, including two with persistent or recurrent HPT. Thirty-three patients underwent neck exploration under local anaesthesia with intravenous sedation. Following parathyroidectomy, intraoperative parathyroid hormone levels normalized in 39 of 40 patients and accurately predicted postoperative eucalcaemia. Intraoperative findings included 37 solitary adenomas, one double adenoma and two carcinomas. One patient with persistent HPT developed severe hypoparathyroidism following targeted parathyroid exploration with autotransplantation. Twenty-nine patients were discharged from hospital on the day of surgery. Nineteen of 21 patients for whom data were available reported an improvement in symptoms.

Conclusion
A focused neck exploration provides a safe and effective alternative to bilateral neck exploration in elderly patients in whom a solitary parathyroid adenoma has been localized before operation. Targeted parathyroidectomy under local anaesthesia is recommended in most elderly patients with HPT.
Limits and drawbacks of video-assisted parathyroidectomy
Authors: Berti P , Materazzi G , Picone A , Miccoli P 
Published: June 2003

Abstract

Background
Minimally invasive video-assisted parathyroidectomy (MIVAP) is a novel minimally invasive approach to primary hyperparathyroidism (PHPT). It is a gasless operation characterized by a single central incision and external retraction. This paper describes the drawbacks and limitations of this procedure based on a 5-year experience and 260 operations.

Methods
Of 364 patients with PHTP, 260 were selected for MIVAP. In most patients a unilateral minimally invasive exploration was performed.

Results
MIVAP was carried out successfully in 239 patients with a mean operating time of 40 (range 20–180) min. Conversion to cervicotomy was required in 21 patients (8·1 per cent). Complications included recurrent nerve palsy in two patients (0·8 per cent), haemorrhage that required reoperation 6 h after parathyroidectomy in one patient (0·4 per cent) and transient hypoparathyroidism in six patients (2·5 per cent). In five patients (2·1 per cent) persistent PHPT developed shortly after surgery.

Conclusion
After 5 years of experience, MIVAP appears to be feasible, safe and applicable to the majority of patients with PHPT.
Letter 1: Systemic inflammatory response predicts survival following curative resection of colorectal cancer (Br J Surg 2003; 90: 215–219)
Authors: Shankar J , Mathew J , Saklani A 
Published: June 2003

Abstract
The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (http://www.bjs.co.uk) or by post. All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk.