bluuebunny/crossref_metadata_2025_split huggingface dataset:
Loss of Heterozygosity on the Short Arm of Chromosome 1 in Pheochromocytoma and Abdominal Paraganglioma
Authors: Edström Elder Elisabeth , Nord Brita , Carling Tobias , Juhlin Claes , Bäckdahl Martin , Höög Anders , Larsson Catharina 
Published: October 2002

Pheochromocytomas and abdominal paragangliomas are catecholamine‐producing tumors that arise from sympathetic paraganglia within and outside the adrenal medulla, respectively. Deletions of the short arm of chromosome 1 have been implicated as important genetic events in their tumorigenesis and suggest a common genetic etiology. The aim of this study was to define further the chromosomal regions on 1p that are involved in the development of these tumor types. We analyzed 46 pheochromocytomas (1 benign, 6
malignant, 9 hereditary) and 7 paragangliomas (3 benign, 4 malignant) from 50
patients for loss of heterozygosity (LOH) on 1p by genotyping 15 microsatellite markers spread over the chromosome arm. Overall, LOH was detected in 33 of 46
pheochromocytomas (72%) and in 6 of 7 (86%) paragangliomas. Three minimal regions of overlapping deletions were identified: one telomeric of D1S1612(1p36.2‐pter), one centromeric of D1S429 (1cen‐p13), and one in the 18 cM interval defined by D1S2134 andD1S1669 (1p32). The latter region harbors the leukocyte common antigen‐related (LAR) gene, which shows altered expression in sporadic rat pheochromocytomas. In conclusion, chromosome
1p may be the site of at least three putative tumor‐suppressor gene loci involved in the tumorigenesis of pheochromocytomas and abdominal paragangliomas. Further studies of these regions and of LARas a candidate gene would be valuable.
Quality of Life and Patient Satisfaction after Reoperation for Primary Hyperparathyroidism: Analysis of Long‐term Results
Authors: Hasse Christian , Sitter Helmut , Brune Melanie , Wollenteit Ina , Nies Christoph , Rothmund Matthias 
Published: October 2002

orbidity after reoperation for persistent or recurrent primary hyperparathyroidism (pHPT) is higher than after primary surgery. According to our experience, there is a contrast between postoperative normalization of laboratory parameters and the quality of life/patient satisfaction after reoperation. Therefore the aim of the study was to analyze the outcomes of reoperations in comparison to primary surgery. We evaluated the patients’ reported quality of life using the SF‐36 (an accepted health status assessment tool) and complete prospectively documented perioperative and follow‐up data including postoperative complications. Additionally, we searched for reasons why primary surgical intervention did not succeed. In a prospective cohort study the perioperative data of 653 consecutive patients with pHPT, including 75 reoperated patients (11.5%) who underwent parathyroidectomy between 1987 and 1999, were evaluated by uni‐ and multivariate analysis. At a median 78 months (6–156 months) postoperatively, all patients underwent a planned follow‐up that included the SF‐36, physical examination, and laboratory investigations. A total of 51 reoperated patients were available for follow‐up. Postoperative alleviation of symptoms or being symptom‐free was reported by 70.6%. Patients after reoperation had lower SF‐36 scores in all health domains postoperatively than patients after a primary operation. Of the reoperated patients, 19.6% stated that after evaluating the development of their complaints they would not consent to reoperation again. Subgroup analysis showed that 80% of patients with postoperatively persistent pHPT, 60% of those who did not observe symptom alleviation, and 44% of those after sternotomy were in the group of dissatisfied patients. Surprisingly, none of the patients with more than one reoperation, only two of the five patients with permanent recurrent laryngeal nerve injury, and only one of the four patients with persistent hypoparathyroidism were dissatisfied overall. Parathyroidectomy resulted in normocalcemia in 90.2% of the reoperated patients, with an operative morbidity of 27.4% and no mortality. After an unsuccessful operation for pHPT, patients should be treated at an expert center to avoid persistent hypercalcemia. Reoperations necessitating sternotomy should be restricted to patients with severe symptoms and signs.
Perinatal outcome of induced and spontaneous pregnancies of primiparous women aged 35 or over
Authors: Kozinszky Z , Orvos H , Katona M , Zoboki T , Pál A , Kovács L 
Published: October 2002

AbstractObjectives: To compare the neonatal and maternal morbidity data associated with induced or naturally conceived pregnancies of primiparous women aged 35 years and older. Methods: We recruited primiparous women aged 35 years and older, who delivered between January 1995 and December 2000. The outcomes of the induced (n=62) and naturally conceived (n=132) pregnancies were compared. The Fisher exact test was used for univariate analysis in order to compare the delivery and pregnancy characteristics in the two groups. Results: Cesarean section featured with a 0.76 times lower prevalence among the induced pregnant women, than among the spontaneous ones, but the difference was not significant statistically. The induced pregnancies were not associated with a significantly higher rate of perinatal complications. Conclusions: Induced pregnancy does not involve a higher risk of maternal complications. The incidence of premature newborns and intrauterine growth retardation was high in both subgroups, but without a statistically significant difference.
Effects of levonorgestrel implant upon TSH and LH levels in male infants during lactation
Authors: Bassol S , Nava‐Hernandez M.P , Hernandez‐Morales C , Trujillo‐Macias A.M , Lopez‐Lozano M.R , Recio R 
Published: October 2002

AbstractObjectives: The objective of the study is to evaluate the effects of levonorgestrel transferred through breast milk on thyroid stimulating hormone (TSH) and luteinizing hormone (LH) levels in full breast‐fed infants. Methods: Forty healthy postpartum women and their male newborns were recruited for the study. Women were randomly allocated to two study groups: Group 1, IUD users and group 2, Norplant® users. Blood and milk samples were collected on the day of IUD or Norplant® insertion and 3 and 6 months later for TSH and levonorgestrel measurements. Results: The results disclosed a significant decrease in TSH levels, and a negative relationship between LNG levels and TSH concentration in breast feeding infants at 3 months after implant insertion. The lowest TSH levels were observed at 6 months in the women from group 2. Conclusions: The overall data indicate that the LNG levels transferred to fully breast‐fed infants through breast milk from Norplant® users significantly modified their TSH levels.
Specific enhancement of acylase I and acylpeptide hydrolase activities by the corresponding N‐acetylated substrates in primary rat hepatocyte cultures
Authors: Perrier Josette , Giardina Thierry , Durand Anne , Puigserver Antoine 
Published: October 2002

AbstractThe specific effects of N‐acetyl‐L‐methionine on acylase I activity and of both N‐acetyl‐L‐alanyl‐L‐alanine and N‐acetyl‐L‐methionyl‐L‐alanine on N‐acylpeptide hydrolase activity were investigated in primary rat hepatocyte cultures. Each of the above two substrates is known to be much more rapidly hydrolyzed than other derivatives of the same type under optimum enzyme assay conditions. After a two‐day incubation of the substrates in the presence of primary rat hepatocyte cultures, the N‐acetylaminoacid was found to specifically induce an increase in the acylase I activity, whereas the two N‐acetylated peptides increased the acylpeptide hydrolase activity in the soluble 100000 × g fraction from the culture medium. No change in any of the enzyme activities could be detected during the same period of time when the medium was not supplemented with N‐acetylated substrates. In addition, the acylase I activity showed a dose dependent response when the N‐acetyl‐L‐methionine concentration increased from 10 fold to 50 fold. It is therefore suggested that the efficient hydrolysis of each type of substrate that occured in the 48 h hepatocyte cell cultures was due to the increase observed in the overall activity of the corresponding enzymes. The ratio of acylpeptide hydrolase to that of acylase I increased considerably when the medium was supplemented with N‐acetylpeptides, and decreased in the presence of the N‐acetylaminoacid.
Work team performance over time: three case studies of South African manufacturers
Authors: Grütter Anton W , Field Joy M , Faull Norman H.B 
Published: October 2002

AbstractIn this paper, we report on three case studies of South African manufacturing firms that made significant efforts to implement shopfloor improvement teams. Following Meredith’s [J. Operat. Manage. 16 (1998) 441] suggestion to use case studies as a basis for theory formulation, insights from the cases were used to extend existing theory by generating hypotheses pertaining to the timing and sustainability of performance gains following the implementation of performance improvement teams, focusing, in particular on ongoing performance improvement teams. Because of the richness of the case study data, we delve deeper than other studies into the actions of teams and management to better understand how and why successful performance improvement teams evolve as they do. Stated in temporal order, our main hypotheses are: work team engagement is positively associated with early implementation credibility‐building activities; both outcome‐orientation and substantive participation are positively associated with a rapid rate of performance gains; and team institutionalization is positively associated with sustaining performance gains. The findings of the case studies and the associated hypotheses are summarized in a time‐phased framework for work team implementation. Limitations and directions for further research are discussed.
Medial collateral ligament autografts have increased creep response for at least two years and early immobilization makes this worse
Authors: Thornton G. M. , Boorman R. S. , Shrive N. G. , Frank C. B. 
Published: October 2002

AbstractRecent evidence has shown that 10–40% of knee joints reconstructed with soft‐tissue autografts have a recurrence of abnormal joint laxity over time. One possible explanation is the “stretching out” (or unrecovered creep) of the graft tissue. To test in vitro creep and creep recovery of fresh anatomic ligament autografts in an extra‐articular environment, 16 rabbits underwent an orthotopic medial collateral ligament (MCL) autograft procedure to one hindlimb. Three subgroups of animals had either unrestricted cage activity for 1 year (n = 5) or 2 years (n = 5) or pin‐immobilization for the first 6 weeks followed by cage activity for the remainder of 1 year (n = 6). Following laxity measurements, to test their creep response, isolated MCL grafts were cyclically and then statically creep tested in vitro at 4.1 MPa, allowed to recover at zero load for 20 min, and finally elongated to failure. Due to differences in cross‐sectional area between the grafts and normal MCLs, two normal control groups were tested: stress‐matched tested at 4.1 MPa (16.2 N; n = 7) and force‐matched tested at 29.1 N (7.1 MPa; n = 6). Ligament grafts had normal laxity but significantly increased creep and decreased creep recovery compared to normal MCLs after 1 and 2 years of healing (p < 0.0004). Graft failure stress was also significantly less than normal (p < 0.0001). Immobilized grafts had significantly greater creep compared to non‐immobilized grafts at 1 year of healing (p < 0.05). These results support previous observations concerning material inferiority of fresh anatomic rabbit MCL autografts, but add the concept that such grafts also have increased potential to creep with either slower or incomplete recovery when subjected to low stresses in vitro. Joint and ligament laxities in situ were normal in this model, however, suggesting either that in vivo MCL graft stresses are lower than those used here in vitro or that these tissues have other mechanisms by which they can recover their functional length in vivo. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Collagen expression and biomechanical response to human recombinant transforming growth factor beta (rhTGF‐β2) in the healing rabbit MCL
Authors: Spindler K. P. , Dawson J. M. , Stahlman G. C. , Davidson J. M. , Nanney L. B. 
Published: October 2002

AbstractWe investigated biomechanical and collagen expression in a healing bilateral rabbit medial collateral ligament (MCL) model to human recombinant transforming growth factor beta (rhTGF‐β2) at three and six weeks. Each rabbit had rhTGF‐β2 in a bioabsorbable pellet administered in one side, with the contralateral side serving as control (no rhTGF‐β2). All MCL healed with rhTGF‐β2 producing a profoundly increased scar mass at three weeks which decreased in size toward control at six weeks. In‐situ hybridization demonstrated collagen expression (type I and III) no different than control at three weeks, but by six weeks elevated expression of type I was seen. Biomechanical analysis at three weeks showed no effect of rhTGF‐β2 on structural properties. However, at six weeks rhTGF‐β2 significantly inhibited both the maximum load (p < 0.05) and energy absorbed (p < 0.05) with no change in stiffness. Despite increased type I collagen expression and profound increase in early scar mass, rhTGF‐β2 did not improve the structural properties. Whether the dose or mode of delivery is responsible for decline in structural properties cannot be determined in this design. We hypothesize investigations of healing ligaments to cytokines should have biologic and biomechanical properties correlated in the same study at a minimum of two time points. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Epidural injection of cyclooxygenase‐2 inhibitor attenuates pain‐related behavior following application of nucleus pulposus to the nerve root in the rat
Authors: Kawakami Mamoru , Matsumoto Takuji , Hashizume Hiroshi , Kuribayashi Koichi , Tamaki Tetsuya 
Published: October 2002

AbstractCyclooxygenase‐2 (COX‐2), the inducible isoform of COX, has been identified as the key enzyme to regulate prostaglandin E2 synthesis in inflammatory conditions. Although it has been reported that COX‐2 is present in herniated disc samples obtained from patients, little is known concerning the relationships between COX‐2 and painful radiculopathy. The purpose of this study was to evaluate whether epidural injection of COX‐2 inhibitor abolishes hyperalgesia induced by nucleus pulposus, which is a pain‐related behavior in the rat. Rats, in which nucleus pulposus was relocated on the nerve root, exhibited evidence of mechanical hyperalgesia. Epidural injection of COX‐2 inhibitor resulted in decrease in mechanical hyperalgesia 1 h, 3 and 7 days after the epidural injection of COX‐2 inhibitor (0.1 mg/kg SC‐236 dissolved in the vehicle). There were no significant differences in sensitivity to thermal noxious stimuli after either application of the nucleus pulposus or epidural injections. These results suggest that prostaglandins and thromboxane, which are produced by COX‐2 in inflammatory cells, appear to be related to the inflammatory process produced by application of nucleus pulposus to the nerve root. It is possible that COX‐2 plays a significant role in painful radiculopathy following herniated nucleus pulposus. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Wrist kinetics after scapholunate dissociation: the effect of scapholunate interosseous ligament injury and persistent scapholunate gaps
Authors: Tang Jin Bo , Ryu Jaiyoung , Omokawa Shohei , Wearden Stanley 
Published: October 2002

AbstractThe purpose of this study was to investigate the effects of cutting of the scapholunate interosseous ligament (SLIL) and persistent widening of the scapholunate (SL) joint on changes in moment arms of the principal wrist motor tendons. In seven fresh frozen cadaveric upper extremities, excursions of the extensor carpi radialis longus (ECRL) and brevis (ECRB), extensor carpi ulnaris (ECU), flexor carpi radialis (FCR), and flexor carpi ulnaris (FCU) were recorded simultaneously with wrist joint angulation during wrist flexion–extension and radioulnar deviation. Tendon excursions were measured in intact wrists, then in the wrists with complete SLIL sectioning and in those with moderate or severe persistent SL joint widening. The data were converted to moment arms of the tendons. The results showed that moment arms of the ECRL and ECRB tendons after SLIL sectioning were, respectively, 110 ± 6% and 105 ± 3% of those in the intact wrist. In the wrists with moderate or severe SL joint widening, moment arms of the flexors significantly increased (P < 0.01 and P < 0.001, respectively). During radioulnar deviation, moment arms of the ECRL, ECRB, ECU, and FCU tendons decreased after SLIL sectioning and the SL joint widening. However, moment arms of the FCR tendon significantly increased 122 ± 23% after the SLIL section, 133 ± 28% after the moderate SL joint widening, and 138 ± 24% after the severe SL joint widening compared with those of the intact wrists. This study demonstrated that integrity of the SLIL and appropriate SL joint space are important for mechanics of wrist motor tendons. Loss of integrity of the SLIL and persistent SL joint widening increase mechanical effects of the radial side wrist motor tendons, which may contribute to the pathomechanics of scaphoid malrotation, scapholunate advanced collapse, and early osteoarthritis in the radioscaphoid joint interface seen in SL dissociation. The results also suggest that reduction of the displaced SL joint is imperative to the recovery of wrist kinetics after SL dissociation. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Endogenous norepinephrine regulates blood flow to the intact rat tibia
Authors: Feitelson J. B. A. , Kulenovic E. , Beck D. J. , Harris P. D. , Passmore J. C. , Malkani A. L. , Fleming J. T. 
Published: October 2002

AbstractThe goal of our study was to determine if endogenous norepinephrine (NE) has a role in the regulation of basal blood flow to intact bone. The experimental plan was to measure bone blood flow before and after pharmacological blockade of alpha‐adrenergic receptors. A significant increase in blood flow after receptor blockade would suggest that endogenous norepinephrine exerts a tonic constrictor effect on the vessels supplying blood to the bone. Mature, male rats were anesthetized with Inactin. Arterial blood pressure and left tibia blood flow (laser Doppler flowmetry) were measured. A cannula was inserted into the right iliac artery and advanced to the aortic bifurcation to deliver drugs into the left hindlimb circulation, including the left tibia vasculature. Bolus injection of norepinephrine caused a dose‐dependent decrease in bone blood flow (30–40%). Blockade of alpha‐adrenergic receptors with phentolamine or phenoxybenzamine attenuated by more than 50% the norepinephrine‐induced decrease in bone blood flow. In separate rats that had not received exogenous norepinephrine, injection of phentolamine alone decreased bone vascular resistance by 34 ± 3%. Similarly, phenoxybenzamine decreased resistance by 25 ± 4%. These results are consistent with the conclusion that alpha‐adrenergic receptors mediate a significant constriction of blood vessels which participate in the partial control of basal blood flow to the intact rat tibia. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
The spatiotemporal expression of TGF‐β1 and its receptors during periosteal chondrogenesis in vitro
Authors: Mizuta Hiroshi , Sanyal Arunik , Fukumoto Takumi , Fitzsimmons James S. , Matsui Nobuzo , Bolander Mark E. , Oursler Merry Jo , O'Driscoll Shawn W. 
Published: October 2002

AbstractTransforming growth factor‐β1 (TGF‐β1) has been shown to stimulate chondrogenesis in periosteal explants cultured in agarose suspension. TGF‐βs exert their cellular effects through a heteromeric cell membrane receptor complex consisting of TGF‐β type I and type II receptors. In this study, the spatial and temporal expressions of the type I receptor (TβR‐I), type II receptor (TβR‐II) and endogenous TGF‐β1 in periosteal explants cultured in vitro were examined using reverse transcription polymerase chain reaction (RT‐TCR) and immunohistochemistry. The temporal changes in the expression of the TβR‐I and TβR‐II mRNAs correlated with that of TGF‐β1. Exogenous administration of TGF‐β1 upregulated the expression of both receptors and of the TGF‐β1 ligand in a biphasic pattern. The earlier peak of upregulation was observed at 7 days in culture. A later peak of upregulation was seen at 42 days, at which time cartilage formation reached a maximum. Immunohistochemical studies demonstrated co‐localization and TβR‐II simultaneously among the same cells expressing TGF‐β1. TGF‐β1 treatment increased the expression of TGF‐β1, I and TβR‐II in mesenchymal cells in the cambium layer at 7 days in culture. Small round chondrocytes showed widely distributed immunoreactivity of TGF‐β1, TβR‐I and TβR‐II in the 42‐day explants treated with TGF‐β1. These observations support the hypothesis that TGF‐β1 regulates the initiation and formation of cartilage during periosteal chondrogenesis. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
The effect of rotator cuff tears on reaction forces at the glenohumeral joint
Authors: Parsons I. M. , Apreleva Maria , Fu Freddie H. , Woo Savio L.‐Y. 
Published: October 2002

AbstractThe rotator cuff muscles maintain glenohumeral stability by compressing the humeral head into the glenoid. Disruption of the rotator cuff compromises concavity compression and can directly affect the loads on the glenohumeral joint. The purpose of this study was to quantify the effect of rotator cuff tears on the magnitude and direction of glenohumeral joint reaction forces during active shoulder abduction in the scapular plane using nine cadaveric upper extremities. Motion of the full upper extremity was simulated using a dynamic shoulder testing apparatus. Glenohumeral joint reaction forces were measured by a universal force–moment sensor. Five conditions of rotator cuff tears were tested: Intact, Incomplete Supraspinatus Tear, Complete Supraspinatus Tear, Supraspinatusl Infraspinatus Tear, and Global Tear. Reaction forces at the glenohumeral joint were found to steadily increase throughout abduction and peaked at maximum abduction for all conditions tested. There were no significant differences in reaction force magnitude for the intact condition (337 ± 88 N) or those involving an isolated incomplete tear (296 ± 83 N) or complete tear (300 ± 85 N) of the supraspinatus tendon. Extension of tears beyond the supraspinatus tendon into the anterior and posterior aspect of the rotator cuff led to a significant decrease in the magnitude of joint reaction force (126 ± 31 N). Similarly, such tears resulted in a significant change in the direction of the reaction force at the glenohumeral joint. These results suggest that joint reaction forces are significantly affected by the integrity of the rotator cuff, specifically, by the transverse force couple formed by the anterior and posterior aspects of the cuff. The quantitative data obtained in this study on the effect of rotator cuff tears on magnitude and direction of the reaction force at the glenohumeral joint helps clarify the relationship between joint motion, joint compression and stability. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.