bluuebunny/crossref_metadata_2025_split huggingface dataset:
Short inversions and conserved gene cluster
Authors: Sankoff David 
Published: October 2002

Abstract
Motivation: Two independent sets of recent observations on newly sequenced microbial genomes pertain to the prevalence of short inversion as a gene order rearrangement process and to the lack of conservation of gene order within conserved gene clusters. We propose a model of inversion where the key parameter is the length of the inverted fragment.
Results: We show that there is a qualitative difference in the pattern of evolution when the inversion length is small with respect to the cluster size and when it is large. This suggests an explanation of the lack of parallel gene order in conserved clusters and raises questions about the statistical validity of putative functionally selected gene clusters if these have only been tested against inappropriate null hypotheses.
Contact: sankoff@poste.umontreal.ca
SPINLESS IMPURITIES IN CUPRATES: LOCAL MAGNETISM AND KONDO EFFECT IN THE NORMAL AND SUPERCONDUCTING STATES
Authors: ALLOUL H. , BOBROFF J. , MENDELS P. , RULLIER-ALBENQUE F. 
Published: October 2002

Spinless point defects in the CuO 2 planes of the cuprates have been shown for long to induce a magnetic response on the neighboring copper sites which behaves as a nearly free local moment in the under-doped case.1,2 In the case of Li + substitution on the Cu site, accurate 7 Li NMR shift data allow to evidence that the local moment susceptibility displays a ( T + T K ) -1 dependence, with a Kondo like temperature T K which increases abruptly near optimal doping.3 While a Curie paramagnetic response can be understood on general theoretical grounds in the case of undoped quantum spin systems, the Kondo screening of the moment might directly reflect the influence of charge carriers. This Kondo like behavior is also corroborated by measurements of the fluctuation time of the local moment deduced from 7 Li NMR spin lattice relaxation time.4 The local moment is found to survive in the superconducting state although a marked reduction of the screening is observed when T K > T c (see Ref. [5]), as might be expected from theoretical considerations. Correlatively it will be shown that the scattering of charge carriers by spinless defects can be studied accurately in single crystals in which such defects are created by electron irradiation. The low T upturns of the resistivity can be associated with a Kondo-like T dependence of the scattering in the under-doped case. In the over-doped case, T K being very high, the scattering becomes T-independent and 2D weak localization effects dominate.6
HIGH PRESSURE TECHNIQUES FOR LOW TEMPERATURE STUDIES IN DC AND PULSED MAGNETIC FIELDS
Authors: TOZER S. W. 
Published: October 2002

Pressure can be used to expand the parameter space available in almost any experiment and allows for the continuous tuning of the electrical and orbital properties of a material. When combined with low temperatures and high magnetic fields, it becomes a powerful tool for the exploration of the band structure and defect levels in semiconductors, exotic transport mechanisms in molecular conductors, and the coexistence of magnetism and superconductivity. We have developed a variety of miniature pressure cells to allow the user to take full advantage of these opportunities. Metallic diamond anvil cells as small as 6 mm in diameter and 8 mm in height allow the sample to be rotated in field at millikelvin temperatures. Miniature plastic DACs and sapphire ball cells, rotators, and specialized He-4 and He-3 systems have also been developed to provide similar experimental capabilities in pulsed magnetic fields. Methods and designs to generate hydrostatic pressure and techniques to perform optical and electrical measurements in DC and pulsed fields will be presented. We would like to acknowledge the technical assistance of Richard Desilets, Howard Kolb, John Farrell, and Mike Pacheco. A portion of this work was performed at the National High Magnetic Field Laboratory, which is sponsored by NSF Cooperative Agreement No. DMR-9527035 and by the State of Florida.
Versatile macrolide‐responsive mammalian expression vectors for multiregulated multigene metabolic engineering
Authors: Weber Wilfried , Marty René R. , Keller Bettina , Rimann Markus , Kramer Beat P. , Fussenegger Martin 
Published: October 2002

AbstractThe novel macrolide‐inducible and ‐repressible mammalian gene regulation systems (E.REX) have been cloned into a variety of sophisticated expression configurations including (1) multi‐purpose expression vectors, (2) pTRIDENT‐based artificial operons, (3) dual‐regulated expression strategies for independent control of two different transgenes, (4) autoregulated vectors for one‐step installation of adjustable multigene expression, and (5) oncoretroviral and lentiviral plasmids for transduction of macrolide‐, streptogramin‐ and tetracycline‐dependent transactivators and production of cell lines supporting independent control of three different transgenes. This vector portfolio represents a construction kit‐like toolbox for efficient installation of adjustable gene expression responsive to clinically licensed antibiotics and enables the design of multiregulated multigene metabolic engineering strategies required for biopharmaceutical manufacturing, gene therapy, and tissue engineering. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 691–705, 2002.
Simultaneous HPLC determination of 5‐fluorouracil and its metabolites in plasma of cancer patients
Authors: Casale F. , Canaparo R. , Muntoni E. , Serpe L. , Zara G.P. , Pepa C. Della , Berno E. , Costa M. , Eandi M. 
Published: October 2002

Abstract5‐Fluorouracil (5‐Fu) is a commonly used anticancer agent for treatment of solid tumours. Certain studies have reported conflicting results between individual plasma concentration levels and toxicity or therapeutic effects. For this reasons some authors proposed to evaluate the plasma levels of 5‐Fu metabolites 5‐fluorouridine, 5‐fluoro‐2′‐deoxyuridine and 5‐fluoro‐5,6‐dihydro‐uracil. The aim of the present work is to develop and validate a new HPLC method simultaneously determining 5‐fluorouracil and its three metabolites, to be used to study the plasma levels, therapeutic effects and toxicity in cancer patients. The analytes were separated on a 4.6 × 250 mm ODS1 (5 µm) not end‐capped column, operating at room temperature. Elution was performed under isocratic conditions, employing a 1.5 mM K3PO4 mobile phase (pH 5). 5‐Bromo‐5,6‐dihydro‐uracil was used as internal standard. The limits of quantitation were 0.5 µg/mL for 5‐fluorouracil, 1 µg/mL for 5‐fluoro‐5,6‐dihydro‐uracil, 3 µg/mL for 5‐fluoro‐2′‐deoxyuridine and 5‐fluorouridine; the stability, recovery, linearity, accuracy and specificity of the compounds were evaluated according to the criteria widely accepted. Using this method we measured plasma samples of 18 cancer patients treated with folinic acid (100 mg/m2) by intravenous administration, followed by an i.v. bolus of 5‐Fu (400 mg/m2). The concentration levels of 5‐fluorouracil and for 5‐fluoro‐5,6‐dihydro‐uracil were detectable in all the subjects while 5‐fluorouridine and 5‐fluoro‐2′‐deoxyuridine were present only in eight patients. Copyright © 2002 John Wiley & Sons, Ltd.
Effect of Saccharomyces cerevisiae fermentation conditions on expanded bed adsorption of heterologous cutinase
Authors: Calado Cecília R C , Cabral Joaquim M S , Fonseca Luis P 
Published: October 2002

AbstractThe effect of culture media composition, and fermentation conditions and strategy on the growth and cutinase production of recombinant Saccharomyces cerevisiae and subsequent cutinase purification by expanded bed adsorption (EBA) was studied. The reduction in the amount of yeast extract used as nitrogen source from 20 g dm−3 to 10 g dm−3 in batch cultures led to a 29% decrease in the heterologous cutinase production, while the 5% cutinase dynamic adsorption capacity (q5%) on the cation Streamline SP XL was increased 6.7‐fold. By dilution of the whole fermentation broth, performed with the lowest yeast extract content, which reduces conductivity, the q5% was additionally increased by 1.9‐fold. After implementation of a fed‐batch strategy the cutinase concentration, cutinase yield on carbon source, cutinase yield on nitrogen source and productivity were increased by 10.8‐, 2.9‐, 5.3‐ and 6.4‐fold, respectively, in relation to the previously‐mentioned batch fermentation. However, the increased cutinase production was compromised by heterologous protein loss during the EBA recovery operation and the cutinase dynamic adsorption capacity and purification productivity decreased by 90% and 75%, respectively. Thus, target protein production by S cerevisiae fermentation and a downstream process with EBA cannot be considered as separate entities, where the understanding of the factors that affect the interactions among them are crucial towards optimization of the overall production process of heterologous proteins.© 2002 Society of Chemical Industry
Perinatal imaging findings of inherited Sotos syndrome
Authors: Chen Chih‐Ping , Lin Shuan‐Pei , Chang Tung‐Yao , Chiu Nan‐Chang , Shih Shin‐Lin , Lin Chen‐Ju , Wang Wayseen , Hsu Hong‐Chih 
Published: October 2002

AbstractObjectivesAlthough most cases of Sotos syndrome are sporadic, familial cases have been described. In familial cases, the most likely mode of inheritance is autosomal dominant with variable expressivity. We present the perinatal imaging findings of an inherited case.CaseThis was the second pregnancy of a 32‐year‐old woman with Sotos syndrome. She had given birth to her first child with macrocephaly, ventriculomegaly, macrocisterna magna and neonatal death at 28 weeks' gestation. During this pregnancy, prenatal ultrasonography at 18 weeks' gestation showed only mild dilatation of lateral ventricles. The pregnancy was uneventful until 31 weeks' gestation when fetal macrocephaly, right hydronephrosis, and polyhydramnios began to develop. At 33 weeks' gestation, dilatation of the third ventricle and fetal overgrowth were obvious. At 34 weeks' gestation, macrodolichocephaly, hypoplasia of the corpus callosum, enlargement of the lateral ventricles with prominent occipital horns, and macrocisterna magna were noted. At 36 weeks' gestation, a male baby was delivered with macrodolichocephaly, frontal bossing and a facial gestalt of Sotos syndrome. Birth weight was 3822 g, length 55 cm, and occipitofrontal head circumference 41 cm (all > 97th centile). The magnetic resonance imaging (MRI) scans demonstrated enlargement of the lateral ventricles, the trigones, and the occipital horns, hypoplasia of the corpus callosum, a persistent cavum septum pellucidum and cavum vergae, and macrocisterna magna.ConclusionsFetuses at risk for Sotos syndrome may present abnormal sonographic findings of the brain and the skull in association with overgrowth, unilateral hydronephrosis and polyhydramnios in the third trimester. Perinatal MRI studies aid in confirmation of the diagnosis. Copyright © 2002 John Wiley & Sons, Ltd.
Necessity of Axillary Dissection in Elderly Women with Early Breast Cancer
Authors: Newlin Matthew E. , Reiling Richard , Nichols Keith 
Published: October 2002

Abstract
The need for axillary dissection for staging and treating early breast cancer has been questioned recently.
Can a patient forego axillary dissection, with its associated costs,
risks, and morbidity, if it does not affect survival? The study attempted to find a subset of patients with early breast cancer in whom disease‐free survival was independent of axillary lymph node status. If survival does not depend on lymph node status, axillary dissection could be omitted in the care of these patients. This study included 378
women over age 70 with T1 breast cancer diagnosed and treated during January 1992 to December 1999 at both of our institutions: a large tertiary teaching hospital in Columbus, Ohio and a breast cancer treatment center in West Columbia, South Carolina. We compared the disease‐free survival, using the Kaplan‐Meier estimate, in 334
node‐negative patients and 44 node‐positive patients with T1 breast cancer. The 3‐ and 5‐year survival rates of patients with T1N0 tumors were 86% and 77%, respectively; and the 3‐ and 5‐year survival rates for T1 node‐positive tumors were 81% and 69%, respectively
(p = 0.0673). There was no statistical difference between the node‐negative and node‐positive groups. Axillary dissection in women over 70 years of age with early breast cancer may be unnecessary, as the presence of lymph node metastases does not appear to affect disease‐free survival rates significantly in this patient group.
Will Directed Parathyroidectomy Utilizing the Gamma Probe or Intraoperative Parathyroid Hormone Assay Replace Bilateral Cervical Exploration as the Preferred Operation for Primary Hyperparathyroidism?
Authors: Burkey Shelby H. , van Heerden Jon A. , Farley David R. , Thompson Geoffrey B. , Grant Clive S. , Curlee Kathleen J. 
Published: October 2002

The trend toward limited exploration for primary hyperparathyroidism (1° HPT) has stemmed from advances in sestamibi scanning, gamma probe technology, and intraoperative parathyroid hormone monitoring (iPTH). Prior to widespread application,
directed parathyroidectomy must be shown to meet the high standards of conventional cervical exploration. In this prospective, nonrandomized trial, results of parathyroidectomy utilizing the gamma probe, iPTH, or neither technique were evaluated. Altogether, 150 patients underwent parathyroidectomy utilizing the gamma probe (n = 50),
iPTH (n = 50), or neither technique
(n = 50). Each group was evaluated for operating time,
length of hospitalization, cure rate, morbidity, mortality, and cost. A telephone survey was conducted with 25 patients in each group
(n = 75) to address patient satisfaction. The gamma probe localized the abnormal gland in 66% of patients and confirmed cure intraoperatively in 84%. In the iPTH group, a more than 50%
decrease from baseline occurred in 98%. The mean operating times were
76, 84, and 90 minutes, respectively (p = 0.16); and the mean length of hospitalization was 1 day. The biochemical cure rates were 98%, 100%, and 96%, respectively (p =
0.17). Total costs were $4476, $3918, and $3905, respectively. A total of 96% of patients in all three groups were "very satisfied" with their surgical procedure. Directed parathyroidectomy utilizing the gamma probe or iPTH assay does not significantly alter the operating time, length of hospitalization, cure rate, morbidity, mortality, or patient satisfaction when compared to conventional exploration in our practice. The probe is more expensive and was not a consistently reliable tool for localizing parathyroid pathology. PTH monitoring reliably predicts cure intraoperatively.
Laparoscopic Adrenalectomy for Pheochromocytoma
Authors: Cheah W. Keat , Clark Orlo H. , Horn Jan K. , Siperstein Allan E. , Duh Quan‐Yang 
Published: October 2002

aparoscopic adrenalectomy is the standard for most surgical adrenal diseases. The aim of this study was to evaluate the safety and effectiveness of laparoscopic adrenalectomy for patients with pheochromocytoma.
The medical records of 39 consecutive patients who underwent laparoscopic adrenalectomy for pheochromocytomas from 1994 to 2000 at the University of California–San Francisco were reviewed. Three groups of patients were identified. The first group comprised 17 patients with classic symptoms and signs of pheochromocytoma. The second group comprised 17 patients who had minimal symptoms and incidentally discovered pheochromocytoma (i.e.,
"incidentaloma"), almost half of whom inappropriately underwent fine‐needle biopsies before diagnosis. The third group consisted of 5 patients who had acute hypertensive crises and required intensive preoperative preparation. The mean age of the 22 men and 17 women was 46 years (range
20–84 years), and the mean adrenal tumor size was 4.8 cm (range
2–12 cm). A total of 43 laparoscopic adrenalectomies were performed for
35 patients with unilateral tumors and 4 patients with bilateral tumors. The retroperitoneal approach was used in four patients and the lateral transabdominal approach in the remaining patients without conversion to an open operation. There were no intraoperative complications or mortality. The mean duration of hospitalization was 1.7 days. In conclusion, patients with pheochromocytoma have a wide spectrum of presentations, from minimal symptoms to hypertensive crises. When evaluating an incidentaloma, pheochromocytoma should be excluded by metabolic testing, not by needle biopsy. Laparoscopic adrenalectomy is the preferred surgical approach for patients with pheochromocytoma because it is safe and efficacious.
Complications of Neck Dissection for Thyroid Cancer
Authors: Cheah W. Keat , Arici Cumhur , Ituarte Philip H.G. , Siperstein Allan E. , Duh Quan‐Yang , Clark Orlo H. 
Published: October 2002

rophylactic and therapeutic neck dissections are used to control or eliminate local nodal disease in patients with thyroid cancer. The purpose of this study was to evaluate the results and complications of neck dissection. From 1992 to 1999 a series of 115 consecutive neck dissections were performed in 74 patients (32 men, 42 women; mean age 48 years)
with thyroid cancer and nodal metastases. Operations included central compartment, lateral modified, and suprahyoid dissection with and without total or completion thyroidectomy. Sixty‐four percent of the patients had papillary,
4% follicular, and 32% medullary thyroid cancer. Complications included transient hypocalcemia (23%) defined by a postoperative serum calcium level of
<2.0 mmol/L (8.0 mg/dl), one neck hematoma (0.9%), and one cardiac death
(0.9%). There were no permanent recurrent nerve palsies. Hypocalcemia occurred more frequently when neck dissection was combined with total thyroidectomy than without it (p <0.005). In this group, the incidence of hypocalcemia was higher after central, than lateral, neck dissection. When neck dissection was performed without thyroidectomy, there was no difference in the rates of hypocalcemia between central, lateral, or central with lateral neck dissection (p = NS).
Hypocalcemia did not increase with repeated neck dissectionsp = NS). Permanent hypoparathyroidism occurred in 0.9%.
There were no complications after suprahyoid dissection. The median duration of hospitalization was 1 day. Therapeutic neck dissection or repeated neck dissection can be performed relatively safely in patients with thyroid cancer.
Hypocalcemia occurs most frequently when neck dissection is combined with total thyroidectomy.
New Point‐of‐care Intraoperative Parathyroid Hormone Assay for Intraoperative Guidance in Parathyroidectomy
Authors: Carneiro Denise M. , Irvin George L. 
Published: October 2002

The use of the intraoperative parathyroid hormone assay (QPTH) to guide a limited parathyroidectomy in patients with sporadic primary hyperparathyroidism (SPHPT) is well established. The advantage of having this assay performed in the operating room is immediate feedback for (1) confirming the complete excision of all hyperfunctioning parathyroid(s); (2) differential jugular venous sampling for localization; and (3) diagnosing suspected tissue without histopathology. For these reasons, the reliability of the hormone measurement and a short assay turnaround time are essential for surgical guidance. We report our experience using a new
"point‐of‐care" assay for intact parathyroid hormone (iPTH). A new two‐site chemiluminescent immunometric assay was used. The antibodies are inside a microtiter well, where the iPTH is measured by a strip luminometer after incubation for 5 minutes. Sixteen frozen samples were measured simultaneously using the traditional iPTH assay and this new assay for comparison. Fifty‐one patients with SPHPT underwent parathyroidectomy guided by this new assay. The criteria used to predict postoperative normocalcemia was a drop in the hormone level of ≤ 50% from the highest preincision or preexcision levels at 10 minutes after excision of all hypersecreting gland(s). The correlation between the traditional and new assays was 0.98. The assay predicted the postoperative calcium levels in all patients except one (false negative‐delayed drop). The assay turnaround time was 8 minutes. This new point‐of‐care assay is reliable for predicting postoperative calcium levels when used with the described criteria. It has advantages over the traditional assay in that it is faster and easier to perform.
Bone‐mass peak in multiparity and reduced risk of bone‐fractures in menopause
Authors: Cure‐Cure C , Cure‐Ramı́rez P , Terán E , López‐Jaramillo P 
Published: October 2002

AbstractObjectives: Pregnancy has been proposed as a risk factor for the development of osteoporosis; however, the results are controversial. Women in Colombia are multiparous, and therefore they represent an ideal population for the investigation of the effect of parity on osteoporosis. Methods: The study included 1855 post‐menopausal Hispanic women from Barranquilla, Colombia who were referred to our osteoporosis clinic for a routine evaluation of their bone mineral status. Bone mineral density (BMD, g/cm2) was measured using dual energy X‐ray absorptiometry. Total body, femoral and lumbar areas were scanned. Results: BMD of total body, hip and legs (P<0.0001), Ward's area (P<0.002) and intertrochanteric area (P<0.003) was high in women with at least one delivery in comparison with nulliparous women. Total mineral and calcium body contents were also high in women after second delivery. A history of fractures was found in 22.9% (n=425) of the study women. The relative risk for bone‐fractures was high (O.R. 0.41; P<0.000002) in nulliparous women in comparison to multiparous women. In addition, osteopenia (O.R. 2.01; P=0.008) and osteoporosis (O.R. 3.99; P=0.0004) were most often present in nulliparous women in comparison to multiparous women. Conclusions: Pregnancies in this population appear to be a protective factor against development of osteoporosis. The increase in total mineral and calcium contents was related to the number of pregnancies, suggesting the existence of a bone mass peak during pregnancy.
Obstetric deaths in Bangladesh, 1996–1997
Authors: Rahman M.H. , Akhter H.H. , Khan Chowdhury M.‐E.‐E. , Yusuf H.R. , Rochat R.W. 
Published: October 2002

AbstractObjectives: The purpose of this study was to measure and to describe obstetric deaths in Bangladesh. Methods: We reviewed hospital records and interviewed health workers in clinic sites and field workers who cared for pregnant women. Results: We obtained case reports of 28 998 deaths of women aged 10–50, of which 8562 (29.5%) were maternal deaths. Most (7086, 82.8%) of these deaths were due to obstetric causes. The most common causes of direct obstetric death were eclampsia (34.3%), hemorrhage (27.9%), and obstructed and/or prolonged labor (11.3%). National direct obstetric death rate was estimated to be 16.9 per 100 000 women. Conclusions: Efforts to reduce fertility in Bangladesh have led to an estimated 49% reduction in the maternal mortality rate per 1000 women during the past 18 years. Variations in maternal mortality suggest the need to develop local strategies to improve obstetric care.