bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of Chromosomal Rearrangements Derived From Homeologous Recombination in Four Mapping Populations of Brassica napus L.
Authors: Udall Joshua A , Quijada Pablo A , Osborn Thomas C 
Published: November 2004

Abstract
Genetic maps of Brassica napus were constructed from four segregating populations of doubled haploid lines. Each mapping population had the same male parent and used the same set of RFLP probes, facilitating the construction of a consensus map. Chromosomal rearrangements were identified in each population by molecular marker analysis and were classified as de novo homeologous nonreciprocal transpositions (HNRTs), preexisting HNRTs, and homeologous reciprocal transpositions (HRTs). Ninety-nine de novo HNRTs were identified by the presence of a few lines having duplication of a chromosomal region and loss of the corresponding homeologous region. These de novo HNRTs were more prevalent in one population that had a resynthesized B. napus as a parent. Preexisting HNRTs were identified by fragment duplication or fragment loss in many DH lines due to the segregation of HNRTs preexisting in one of the parents. Nine preexisting HNRTs were identified in the three populations involving natural B. napus parents, which likely originated from previous homeologous exchanges. The male parent had a previously described HRT between N7 and N16, which segregated in each population. These data suggest that chromosomal rearrangements caused by homeologous recombination are widespread in B. napus. The effects of these rearrangements on allelic and phenotypic diversity are discussed.
Role of bilateral adrenalectomy in Cushing's disease
Authors: Favia Gennaro , Boscaro Marco , Lumachi Franco , D'Amico Davide F. 
Published: October 2004

AbstractOf 206 patients with Cushing's syndrome observed from 1975 through 1991, 144 (69.9%) had pituitary‐dependent Cushing's disease. Of the 110 patients who underwent pituitary surgery, 31 (28%) developed an early recurrence and 23 patients (20%) had a late relapse 1 to 5 years after primary pituitary exploration. We performed a one‐ or two‐step total bilateral adrenalectomy in 43 patients—9 men and 34 (79.4%) women, with an average age of 47.5 years (range 13–58 years). Thirty‐three of these patients had already been treated by previous transsphenoidal surgery or alternatively by external pituitary irradiation over a period of 1 to 10 years prior to adrenal surgery. Thirty‐one patients underwent adrenalectomy by a double lumbar access or left lumbar and right subcostal incisions. In our series of 55 operations, perioperative complications included two splenectomies and two hemorrhages (7.3%). The early mortality rate was 3.6% (two patients). Minor complications consisted of wound infection (13.5%), bronchopneumonia or pneumothorax (four cases) with a 7‐ to 12‐day longer hospital stay. Nelson syndrome occurred in 6 of 41 patients (14.6%). We therefore believe that bilateral adrenalectomy does play a major role in the treatment of patients with pituitary‐dependent Cushing's disease unsuccessfully managed by trans‐sphenoidal surgery. It represents the definitive therapy for those patients in whom hypophysectomy was not able to provide satisfactory control of the disease.
“The” pheochromocytoma: A benign, intra‐adrenal, hypertensive, sporadic unilateral tumor. Does it exist?
Authors: Proye Charles A. G. , Edbg F. R. C. S. , Vix Michel , Jansson Svante , Tisell Lars‐E. , Dralle Hennig , Hiller Wolfgang 
Published: October 2004

AbstractThis study aims to examine the frequency of the pheochromocytoma (pheo), defined as a “benign, intra‐adrenal, hypertensive, sporadic, unilateral tumor.” Three large series amounting to 310 subphrenic chromaffin tumors operated over periods of 17, 23, and 41 years, respectively, have been reviewed. Among those combined 310 pheos, 48 (15.5%) were malignant (i.e., metastatic) and 262 (84.5%) were benign; 42 (13.5%) were ectopic (35% of malignant tumors versus 9.5% of benign tumors); 230 (74.2%) were hypertensive (74% of benign tumors versus 73% of malignant tumors); 29 (9.4%) were bilateral, including 23 patients with a family history; 41 (13.2%) of patients had MEN II type A or B syndrome; and 20 (6.5%) occurred in a phacomatosis setting. Some of the patients had a non‐MEN family history of pheo (n=5), seemingly sporadic hyperparathyroidism (n=4), or other associated neuroendocrine tumor (n=9). Sometimes several of these features were combined. Finally 125 (40.3%) cases fitted the classic description of the tumor, 47.0% at the time of initial presentation and 40.3% at the end of follow‐up. Late occurrence of metastases or metachronous diagnosis of familial disease make lifelong follow‐up mandatory. Genetic studies may be indicated in pheochromocytoma patients.
Fate of untreated benign thyroid nodules: Results of long‐term follow‐up
Authors: Kuma Kanji , Matsuzuka Fumio , Yokozawa Tamotsu , Miyauchi Akira , Sugawara Masahiro 
Published: October 2004

AbstractThe fate of benign thyroid nodules has been unknown because there has been no study in this regard. We re‐examined 134 patients with thyroid nodules who had had benign aspiration biopsy cytology 9 to 11 years ago. The thyroid gland was palpated by the same two thyroidologists throughout the study. Ultrasonography, fine‐needle aspiration biopsy (FNAB), and ultrasound‐guided FNAB were employed to examine the nature of nodules of 9 to 11 years' duration. Patients (n=61) who had nodules difficult to palpate (small nodules), multiple nodules, or cystic nodules with papillomatous proliferation underwent ultrasound‐guided PNAB; patients (n=55) having a distinctly palpable single nodule underwent usual FNAB. None of the patients received any medical or surgical treatment. There were 86 single nodules, 14 multiple nodules, and 34 cystic nodules on the first examination. These benign nodules were reexamined for changes in size and cytology 9 to 11 years later. The most striking finding was a decrease in size or disappearance of the nodule in 42% to 79% of benign nodules. About 92% of nodules remained benign without changing cytologic classification. Only one case (0.9%) previously regarded as benign turned out to be malignant; this nodule grew in size compared with the previous examination. Among single and multiple nodules, 21% to 23% of the nodules increased in size; however, most patients with enlarged nodules (86%) showed the same class 2 cytology as before. Our present study indicates that biopsy‐proved benign thyroid nodules remain benign over a prolonged period. Thus no medical or surgical treatment is required so long as the nodules do not grow.
Proton magnetic resonance and human thyroid neoplasia II: Potential avoidance of surgery for benign follicular neoplasms
Authors: Delbridge Leigh , Lean Cynthia L. , Russell Peter , May George L. , Roman Sandrine , Dowd Susan , Reeve Thomas S. , Mountford Carolyn E. 
Published: October 2004

AbstractThyroid cancer is rare, but many thyroidectomies continue to be performed simply to exclude a diagnosis of malignancy. The purpose of this study was to determine the potential financial savings associated with the use of proton magnetic resonance analysis of follicular neoplasms. Proton magnetic resonance spectroscopy was performed on tissue obtained at the time of surgery from 98 consecutive solitary or dominant thyroid nodules. Fine‐needle biopsies were also performed on operative specimens, and the tissues assessed by proton magnetic resonance; these spectra were then compared with those obtained from tissue specimens. An estimate of potential savings was obtained by comparing the magnetic resonance data with the indications for surgery and pathology on all patients having thyroidectomy over a 10‐year period. Proton magnetic resonance spectroscopy was able to distinguish between normal thyroid tissue and invasive thyroid cancer with 100% specificity. Benign follicular adenomas fall into two groups: 44% having a spectral pattern comparable with normal thyroid, and the remaining 56% demonstrating an altered spectral pattern more comparable to the malignant magnetic resonance profile. Proton magnetic resonance spectroscopy on fine‐needle biopsy specimens produced spectra similar to those from tissues from the same patient. From a fine‐needle biopsy specimen, proton magnetic resonance spectroscopy can identify a group of benign follicular adenomas with spectral profiles akin to those of normal thyroid cells, thus avoiding the need for unnecessary surgical excision. The potential savings in one surgical unit alone were over $1 million in 10 years.
Prognostic significance and surgical management of locoregional lymph node metastases in papillary thyroid cancer
Authors: Scheumann Georg F. W. , Gimm Oliver , Wegener Gerd , Hundeshagen H. , Dralle Henning 
Published: October 2004

AbstractWe studied the records of 342 patients with papillary thyroid carcinoma out of a total of 728 thyroid cancer patients treated at the Medical School of Hannover (MHH) from 1972 through 1992. The comprehensive data‐abstracting forms were designed, and the acquired information was coded, stored, maintained, and evaluated by the Clinical Cancer Registry of the MHH. A total of 160 patients (46.8%) initially had lymph node metastases (N1 status). The N status significantly influenced recurrence (p<0.00001) and survival (p<0.00001). Excluding other risk factors developed by univariate and multivariate analysis, such as high age (age >45 years, p<0.001), tumor invasion (T4 tumor, p<0.005), and distant metastases (M1, p<0.001), lymph node metastases remained an independent, highly significant prognostic marker for more aggressive papillary thyroid cancer. N1 status did not influence survival of patients with T4 tumor but did influence those with T1–T3 status (p<0.001). The influence of N1 status remained significant in patients older (p<0.001) and younger (p<0.05) than 45 years of age. Systematic compartmentoriented dissection of lymph node metastases improved survival (p<0.005, T1–T3) and recurrence (p<0.00001, T1–T3) especially in patients with T1–T3 tumors. In conclusion, lymph node metastases with a significant incidence at a young age and male sex had a substantial effect on survival and recurrence especially in those with tumor status T1–T3. Systematic compartment‐oriented dissection of the lymph node metastases results in better survival and a lower recurrence rate.
Diminished expression of the α5β1 integrin (fibronectin receptor) by invasive clones of a human follicular thyroid cancer cell line
Authors: Demeure Michael J. , Doffek Kara M. , Rezaee Mehrdad , Goretzki Peter E. , Wilson Stuart D. 
Published: October 2004

AbstractAltered adhesion plaques have been observed in transformed cell lines and are associated with enhanced metastatic potential. The prototypical adhesion plaque is formed by α5β1 fibronectin receptors (FnRs) interacting with the cellular actin network. We have found differences in the actin networks of noninvasive (FTC‐133) and invasive (FTC‐236, FTC‐238) clones of a human follicular thyroid cancer cell line. Furthermore, thyroid‐stimulating hormone (TSH) induces stress fibers in FTC‐133. In order to investigate differences in adhesion plaques, expression of fibronectin (FN) and its receptor by these cells was analyzed. For these studies FTC‐133, FTC‐236, and FTC‐238 were cultured in serum‐depleted DME‐H21 medium for 24 hours before the addition of TSH 30 mU/ml. No quantitative differences were noted in FN expression on Western blot in either the conditioned medium or cellular extracts. Western blots and immunohistochemical studies indicated that TSH induced secretion of FN only in FTC‐133. Flow cytometry with an α5 antibody demonstrated a 52% and 45% reduction (p<0.01) in expression of FnR by FTC‐236 and FTC‐238, respectively, compared to FTC‐133; this finding was supported by immunohistochemistry results. TSH treatment did not alter FnR expression. From these studies, we conclude that invasive clones of FTC decrease their expression of FnRs without changing their expression of FN. Furthermore, TSH treatment may promote FN secretion by FTC‐133, although it does not seem to affect FnR or absolute FN expression. The diminished expression of FnR adhesion plaques may enhance metastatic potential in some follicular thyroid cancers.
Parathyroid localization by catheterization of large cervical and mediastinal veins to determine serum concentrations of intact parathyroid hormone
Authors: Nilsson Bengt E. , Tisell Lars‐Erik , Jansson Svante , Zackrisson Bo‐Fredrik , Lindstedt Göran , Lundberg Per‐Arne 
Published: October 2004

AbstractA success rate of about 90% has been achieved after primary operations for hyperparathyroidism, compared with 60% to 80% in most series of secondary operations. The present reoperative series involved 29 patients who underwent venous catheterization with blood sampling for the determination of intact parathyroid hormone before undergoing repeat parathyroid surgery. Blood samples were taken from the internal jugular veins, innominate veins, and superior caval vein. No attempt was made to perform superselective catheterization of the small neck and mediastinal veins. The reoperations were done by four surgeons who did 1, 2, 13, and 13 of the reoperations, respectively. In all patients, distinct step‐ups in parathyroid hormone concentrations were found. On average, the gradient between the highest and lowest value was about 5. Close to the location of the step‐ups, diseased parathyroid tissue was found in 27 of the patients. In two cases no parathyroid tissue was found, and these patients remained hyperparathyroid postoperatively. They had been treated by the surgeon who did only two of the operations. When the step‐up was observed in the left innominate vein, we could not differentiate mediastinal from low cervical adenomas. No patient developed hypoparathyroidism. To avoid this complication, autotransplantation of diseased parathyroid tissue into the abdominal subcutaneous fat was done in nine patients. No case of recurrent laryngeal nerve paralysis occurred. The introduction of reliable assays for the analysis of parathyroid hormone can make selective catheterization unnecessary when localizing remaining parathyroid glands in patients with persistent hyperparathyroidism.
Primary hyperparathyroidism and the heart: Cardiac abnormalities correlated to clinical and biochemical data
Authors: Längle Friedrich , Abela Claudette , Koller‐Strametz Janette , Mittelböck Martina , Bergler‐Klein Jutta , Stefenelli Thomas , Woloszczuk Wolfgang , Niederle Bruno 
Published: October 2004

AbstractComparing patients with primary hyperparathyroidism (PHP) to a normocalcemic control population, those with PHP have a higher incidence of cardiovascular disease and cardiac abnormalities. This study aimed at correlating cardiac findings (valvular and myocardial calcification, myocardial hypertrophy) with clinical data (age, sex, clinical manifestation, nephrolithiasis, nephrocalcinosis, hypertension, skeletal abnormalities, hypercalcemic syndrome) and biochemical data (serum calcium, serum phosphate, serum iPTH level, serum creatinine). A group of 132 consecutive patients with surgically verified PHP (94 women, 38 men; ages 15–86, mean age 57±16 years) were included in this study. Blood chemistry, clinical presentation, radiography, and echocardiography were carried out in all patients for univariate and multivariate analyses of all parameters. There was no statistical correlation between clinical symptoms, biochemical data, and cardiac calcific alterations. Typical skeletal manifestations (osteolysis/subperiostal resorption) and valvular calcifications were significantly correlated to left ventricular hypertrophy (p=0.005). Cardiac abnormalities such as calcific myocardial deposits or mitral and aortic valvular calcifications do not correlate with laboratory findings and clinical presentation at the time of diagnosis. There was no biochemical or clinical variable that could predict the frequency or severity of valvular sclerosis or calcific deposits in the myocardium. However, PHP‐related skeletal abnormalities and valvular calcification were predicting factors for left ventricular hypertrophy, a reversible cardiac manifestation of PHP. Myocardial hypertrophy is more often found with classic symptomatic PHP with osseous abnormalities.
Characteristics of Zinc Transport by Two Bacterial Cation Diffusion Facilitators from
Ralstonia metallidurans
CH34 and
Escherichia coli
Authors: Anton Andreas , Weltrowski Annett , Haney Christopher J. , Franke Sylvia , Grass Gregor , Rensing Christopher , Nies Dietrich H. 
Published: October 2004

ABSTRACT

CzcD from
Ralstonia metallidurans
and ZitB from
Escherichia coli
are prototypes of bacterial members of the cation diffusion facilitator (CDF) protein family. Expression of the
czcD
gene in an
E. coli
mutant strain devoid of
zitB
and the gene for the zinc-transporting P-type ATPase
zntA
rendered this strain more zinc resistant and caused decreased accumulation of zinc. CzcD, purified as an amino-terminal streptavidin-tagged protein, bound Zn
2+
, Co
2+
, Cu
2+
, and Ni
2+
but not Mg
2+
, Mn
2+
, or Cd
2+
, as shown by metal affinity chromatography. Histidine residues were involved in the binding of 2 to 3 mol of Zn
2+
per mol of CzcD. ZitB transported
65
Zn
2+
in the presence of NADH into everted membrane vesicles with an apparent

K
m

of 1.4 μM and a
V
max
of 0.57 nmol of Zn
2+
min
−1
mg of protein
−1
. Conserved amino acyl residues that might be involved in binding and transport of zinc were mutated in CzcD and/or ZitB, and the influence on Zn
2+
resistance was studied. Charged or polar amino acyl residues that were located within or adjacent to membrane-spanning regions of the proteins were essential for the full function of the proteins. Probably, these amino acyl residues constituted a pathway required for export of the heavy metal cations or for import of counter-flowing protons.
Evolutionary Dynamics of Insertion Sequences in
Helicobacter pylori
Authors: Kalia Awdhesh , Mukhopadhyay Asish K. , Dailide Giedrius , Ito Yoshiyki , Azuma Takeshi , Wong Benjamin C. Y. , Berg Douglas E. 
Published: October 2004

ABSTRACT

Prokaryotic insertion sequence (IS) elements behave like parasites in terms of their ability to invade and proliferate in microbial gene pools and like symbionts when they coevolve with their bacterial hosts. Here we investigated the evolutionary history of IS
605
and IS
607
of
Helicobacter pylori
, a genetically diverse gastric pathogen. These elements contain unrelated transposase genes (
orfA
) and also a homolog of the
Salmonella
virulence gene
gipA
(
orfB
). A total of 488 East Asian, Indian, Peruvian, and Spanish isolates were screened, and 18 and 14% of them harbored IS
605
and IS
607
, respectively. IS
605
nucleotide sequence analysis (
n
= 42) revealed geographic subdivisions similar to those of
H. pylori
; the geographic subdivision was blurred, however, due in part to homologous recombination, as indicated by split decomposition and homoplasy tests (homoplasy ratio, 0.56). In contrast, the IS
607
populations (
n
= 44) showed strong geographic subdivisions with less homologous recombination (homoplasy ratio, 0.2). Diversifying selection (ratio of nonsynonymous change to synonymous change, ≫1) was evident in ∼15% of the IS
605 orfA
codons analyzed but not in the IS
607 orfA
codons. Diversifying selection was also evident in ∼2% of the IS
605 orfB
and ∼10% of the IS
607 orfB
codons analyzed. We suggest that the evolution of these elements reflects selection for optimal transposition activity in the case of IS
605 orfA
and for interactions between the OrfB proteins and other cellular constituents that potentially contribute to bacterial fitness. Taken together, similarities in IS elements and
H. pylori
population genetic structures and evidence of adaptive evolution in IS elements suggest that there is coevolution between these elements and their bacterial hosts.
Sequence Organization and Insertion Specificity of the Novel Chimeric IS
Hp609
Transposable Element of
Helicobacter pylori
Authors: Kersulyte Dangeruta , Kalia Awdhesh , Zhang MaoJun , Lee Hae-Kyung , Subramaniam Dharmalingam , Kiuduliene Levute , Chalkauskas Henrikas , Berg Douglas E. 
Published: October 2004

ABSTRACT

Here we describe IS
Hp609
of
Helicobacter pylori
, a new member of the IS
605
mobile element family that is novel and contains two genes whose functions are unknown,
jhp960
and
jhp961
, in addition to homologs of two other
H. pylori
insertion sequence (IS) element genes,
orfA
, which encodes a putative serine recombinase-transposase, and
orfB
, whose homologs in other species are also often annotated as genes that encode transposases. The complete four-gene element was found in 10 to 40% of strains obtained from Africa, India, Europe, and the Americas but in only 1% of East Asian strains. Sequence comparison of 10 representative IS
Hp609
elements revealed higher levels of DNA sequence matches (99%) than those seen in normal chromosomal genes (88 to 98%) or in other IS elements (95 to 97% for IS
605
, IS
606
, and IS
607
) from the same
H. pylori
populations. Sequence analysis suggested that IS
Hp609
can insert at many genomic sites with its left end preferentially next to TAT, with no target specificity for its right end, and without duplicating or deleting target sequences. A deleted form of IS
Hp609
, containing just
jhp960
and
jhp961
and 37 bp of
orfA
, found in reference strain J99, was at the same chromosomal site in 15 to 40% of the strains from many geographic regions but again in only 1% of the East Asian strains. The abundance and sequence homogeneity of IS
Hp609
and of this nonmobile remnant suggested a recent bottleneck and then rapid spread in
H. pylori
populations, possibly selected by the contributions of the elements to bacterial fitness.
Increased Motility ofEscherichia coliby Insertion Sequence Element Integration into the Regulatory Region of theflhDOperon
Authors: Barker Clive S. , Prüß Birgit M. , Matsumura Philip 
Published: October 2004

ABSTRACTTheflhDoperon is the master operon of the flagellar regulon and a global regulator of metabolism. The genome sequence of theEscherichia coliK-12 strain MG1655 contained an IS1insertion sequence element in the regulatory region of theflhDpromoter. Another stock of MG1655 was obtained from theE. coliGenetic Stock Center. This stock contained isolates which were poorly motile and had no IS1element upstream of theflhDpromoter. From these isolates, motile subpopulations were identified after extended incubation in motility agar. Purified motile derivatives contained an IS5element insertion upstream of theflhDpromoter, and swarm rates were sevenfold higher than that of the original isolate. For a motile derivative, levels offlhDtranscript had increased 2.7-fold, leading to a 32-fold increase infliAtranscript and a 65-fold increase inflhB::luxCDABEexpression from a promoter probe vector. A collection of commonly used lab strains was screened for IS element insertion and motility. Five strains (RP437, YK410, MC1000, W3110, and W2637) contained IS5elements upstream of theflhDpromoter at either of two locations. This correlated with high swarm rates. Four other strains (W1485, FB8, MM294, and RB791) did not contain IS elements in theflhDregulatory region and were poorly motile. Primer extension determined that the transcriptional start site offlhDwas unaltered by the IS element insertions. We suggest that IS element insertion may activate transcription of theflhDoperon by reducing transcriptional repression.