bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence of spina bifida and anencephaly during the transition to mandatory folic acid fortification in the United States
Authors: Williams Laura J. , Mai Cara T. , Edmonds Larry D. , Shaw Gary M. , Kirby Russell S. , Hobbs Charlotte A. , Sever Lowell E. , Miller Lisa A. , Meaney F. John , Levitt Miriam 
Published: August 2002

AbstractBackgroundIn 1992, the United States Public Health Service recommended that all women of childbearing age consume 400 μg of folic acid daily. The Food and Drug Administration authorized the addition of synthetic folic acid to grain products in March 1996 with mandatory compliance by January 1998. The impact of these public health policies on the prevalence of neural tube defects needs to be evaluated. We sought to determine the prevalences of spina bifida and anencephaly during the transition to mandatory folic acid fortification.MethodsTwenty‐four population‐based surveillance systems were used to identify 5,630 cases of spina bifida and anencephaly from 1995–99. Cases were divided into three temporal categories depending on whether neural tube development occurred before folic acid fortification (January 1995 to December 1996), during optional fortification (January 1997 to September 1998), or during mandatory fortification (October 1998 to December 1999). Prevalences for each defect were calculated for each time period. Data were also stratified by programs that did and did not ascertain prenatally diagnosed cases.ResultsThe prevalence of spina bifida decreased 31% (prevalence ratio [PR] = 0.69, 95% confidence interval [CI] = 0.63–0.74) from the pre‐ to the mandatory fortification period and the prevalence of anencephaly decreased 16% (PR = 0.84, 95% CI = 0.75–0.95). Stratification by prenatal ascertainment did not alter results for spina bifida but did impact anencephaly trends.ConclusionsThe decline in the prevalence of spina bifida was temporally associated with folic acid fortification of US grain supplies. The temporal association between fortification and the prevalence of anencephaly is unclear. Teratology 66:33–39, 2002. Published 2002 Wiley‐Liss, Inc.
Teratogen update: Inorganic arsenic
Authors: DeSesso John M. 
Published: August 2002

AbstractBackgroundInorganic arsenic has been used by many laboratories to study the pathogenesis of exencephaly in rodents. These studies, which used predominantly injection exposures, coupled with the paucity of epidemiology data, resulted in the erroneous inference that inorganic arsenic should be considered a human teratogen.MethodsThis study assembles and assesses literature analyses of older human and animal investigations together with the results of new experimental studies. These recent studies were performed according to modern regulatory guidelines, and relevant exposure routes (inhalation and ingestion) were used to evaluate the potential risk of developmental effects in humans.ResultsThe existing epidemiological data are inadequate to support risk assessment because of the failure to confirm or measure arsenic exposure during early gestation and the deficiencies in accounting for potential confounding factors. The animal data revealed that inorganic arsenic caused malformations in offspring only when it was injected into the veins or peritoneal cavity of pregnant animals during early gestation. Exposure via inhalation or oral ingestion, even at concentrations that were nearly fatal to pregnant females, caused no arsenic‐related malformations.ConclusionsInorganic arsenic poses virtually no danger to developing offspring when maternal exposure occurs by relevant routes (oral and inhalation) at concentrations that are likely to be experienced in the environment or in the workplace. Teratology 64:170–173, 2001. © 2001 Wiley‐Liss, Inc.
The fate of diesel hydrocarbons in soils and their effect on the germination of perennial ryegrass
Authors: Siddiqui Samina , Adams W. A. 
Published: August 2002

AbstractHydrocarbon contamination in soils may be toxic to plants and soil microorganisms and act as a source of groundwater contamination. The objective of this study was to evaluate the fate of diesel in soils with or without added nutrients. The soils examined either had or had not a previous history of hydrocarbon contamination. Particular aspects examined were soil respiration, changes in microbial population, breakdown of diesel hydrocarbons, and phytotoxicity to the germination of perennial ryegrass. Soil respiration was measured as evolved CO2. Bacterial population was determined as colony forming units in dilution plates and fungal activity was measured as hyphal length. The fate of individual hydrocarbons was determined by gas chromatography–mass spectrometry after extraction with dichloromethane. When diesel was added to soil with no previous history of hydrocarbon contamination at rates up to 50 mg/g, the respiration response showed a lag phase of 6 days and maximum respiration occurred at day 11. The lag phase was 2 days and maximum respiration occurred at day 3 in soil with a previous history of hydrocarbon contamination. After the peak, respiration decreased up to about 20 days in both soils. Thereafter, respiration become more or less constant but substantially greater than the control. N and P addition along with diesel did not reduce the lag phase but increased the respiration over the first 20 days of incubation. Diesel addition with or without N and P increased the bacterial population 10‐ to 100‐fold but fungal hyphal length did not increase. Diesel addition at a rate of 136 mg/g did not increase the microbial population. Removal of inhibition to germination of perennial ryegrass was linked to the decomposition of nC10 and nC11 hydrocarbons and took from 11 to 30 days at diesel additions up to 50 mg/g depending on the soil. Inhibition to germination of perennial ryegrass persisted to more than 24 weeks at the 136 mg/g of diesel addition. © 2002 by Wiley Periodicals, Inc. Environ Toxicol 17: 49–62, 2002
Lightning protection for wind turbine blades and bearings
Authors: Cotton Ian , Jenkins Nick , Pandiaraj Krishnan 
Published: August 2002

AbstractThe protection of wind turbines from lightning damage is increasingly important as they increase in size and are placed in locations where access to carry out repairs may be difficult. As blades are the most common attachment point of lightning, they must be adequately protected. In addition, the passage of lightning current through wind turbine bearings introduces a risk of lightning damage to these vital components. Investigations relating to the improvement of blade lightning protection systems have been carried out, including experiments designed to address the difficult problems involved in the protection of hydraulic cylinders used for tip brake control. Work has also focused on the ability of lightning current to cause damage to wind turbine bearings. The work has been a mixture of computer simulations and experimental testing using high‐voltage and high‐current facilities. Copyright © 2001 John Wiley & Sons, Ltd.
Marker‐fusion PCR for one‐step mutagenesis of essential genes in yeast
Authors: Kitazono Ana A. , Tobe Brian T. D. , Kalton Helen , Diamant Noam , Kron Stephen J. 
Published: August 2002

AbstractWe describe a one‐step gene replacement method based on fusion PCR that can be used to mutagenize essential genes at their endogenous locus. Marker‐fusion PCR can facilitate transfer of alleles between strains as well as PCR‐based techniques, such as site‐directed and error‐prone PCR mutagenesis, all without cloning or strain constructions. With this method, PCR is used to fuse a mutagenized fragment to an overlapping fragment containing a selectable marker flanked by regions of homology to the target. By transforming yeast with these PCR products, specific mutations are introduced at the endogenous locus through homologous recombination. We tested the ‘marker‐fusion PCR’ method using the budding yeast CDC28 gene and were able to efficiently introduce site‐directed mutations and integrate genomic or plasmid‐borne mutant alleles. As a further application for this method, we used a spiked oligonucleotide to randomize the coding sequence for a single domain of CDC28 and were able to construct highly mutagenized libraries for this region. Copyright © 2002 John Wiley & Sons, Ltd.
A second Zn(II)2Cys6 transcriptional factor encoded by the YNA2 gene is indispensable for the transcriptional activation of the genes involved in nitrate assimilation in the yeast Hansenula polymorpha
Authors: Ávila Julio , González Celedonio , Brito Nélida , Machín, M Félix , Pérez Dolores , Siverio José M. 
Published: August 2002

AbstractNitrate assimilation genes encoding a nitrate transporter (YNT1), nitrite reductase (YNI1), a Zn(II)2Cys6 transcriptional factor involved in nitrate induction (YNA1) and the nitrate reductase (YNR1) are clustered in the yeast Hansenula polymorpha. A second gene, termed YNA2 (yeast nitrate assimilation), was located seven nucleotides away from the 3′ region of YNR1 gene. The cluster is flanked by an ORF encoding a protein with similarity to glutathione‐S‐transferase on the YNT1 side and an ORF with similarity to Saccharomyces cerevisiae Rad3p on the YNA2 side. The disruption of YNA2 confers the resulting null mutant strain with inability to grow in nitrate. The YNA2 gene encodes a putative protein of 618 residues bearing in the N‐terminus the consensus sequence Cys–X2–Cys–X6–Cys–X5–16–Cys–X2–Cys–X6–8–Cys characteristic of the Zn(II)2Cys6 transcriptional factors. YNA2 is therefore a member of the H. polymorpha nitrate assimilation gene cluster which is transcribed in the opposite direction to the rest of the members. Yna2p shares about 27% similarity with the H. polymorpha Yna1p Zn(II)2Cys6 transcriptional factor involved in nitrate induction. Unlike the wild‐type, the yna2::URA3 strain showed no expression of the nitrate assimilation genes when incubated in nitrate for 2 h. With regard to YNA2 expression, similar YNA2 transcript levels were observed in ammonium and in ammonium plus nitrate, but about a four‐fold higher expression was observed in nitrate. However, this induction by nitrate of the YNA2 gene was not observed in the Δyna1::URA3 strain. On the contrary, the pattern of YNA1 expression was the same in the wild‐type as in the yna2::URA3 strain, indicating that YNA2 does not affect YNA1 expression. The nucleotide sequence Accession No. for YNA2 is AJ223294. Copyright © 2002 John Wiley & Sons, Ltd.
How many protein‐coding genes are there in the Saccharomyces cerevisiae genome?
Authors: Mackiewicz Pawel , Kowalczuk Maria , Mackiewicz Dorota , Nowicka Aleksandra , Dudkiewicz Malgorzata , Laszkiewicz Agnieszka , Dudek Miroslaw R. , Cebrat Stanislaw 
Published: August 2002

AbstractWe have compared the results of estimations of the total number of protein‐coding genes in the Saccharomyces cerevisiae genome, which have been obtained by many laboratories since the yeast genome sequence was published in 1996. We propose that there are 5300–5400 genes in the genome. This makes the first estimation of the number of intronless ORFs longer than 100 codons, based on the features of the set of genes with phenotypes known in 1997 to be correct. This estimation assumed that the set of the first 2300 genes with known phenotypes was representative for the whole set of protein‐coding genes in the genome. The same method used in this paper for the approximation of the total number of protein‐coding sequences among more than 40 000 ORFs longer than 20 codons gives a result that is only slightly higher. This suggests that there are still some non‐coding ORFs in the databases and a few dozen small ORFs, not yet annotated, which probably code for proteins. Copyright © 2002 John Wiley & Sons, Ltd.
Isolation and mapping of self‐assembling protein domains encoded by the Saccharomyces cerevisiae genome using λ repressor fusions
Authors: Mariño‐Ramírez Leonardo , Hu James C. 
Published: August 2002

AbstractUnderstanding how proteins are able to form stable complexes is of fundamental interest from the perspective of protein structure and function. Here we show that λ repressor fusions can be used to identify and characterize homotypic interaction domains encoded by the genome of Saccharomyces cerevisiae, using a selection for polypeptides that can drive the assembly of the DNA binding domain of bacteriophage λ repressor. Three high complexity libraries were constructed by cloning random fragments of S. cerevisiae DNA as λ repressor fusions. Repressor fusions encoding homotypic interactions were recovered, identifying oligomerization units in 35 yeast proteins. Seventeen of these interaction domains have not been previously reported, while the other 18 represent homotypic interactions that have been characterized at varying levels of detail. The novel interactions include several predicted coiled‐coils as well as domains of unknown structure. With the availability of genomic sequences it should be possible to apply this approach, which provides information about protein–protein interactions that is complementary to that obtained from yeast two‐hybrid screens, on a genome‐wide scale in yeast or other organisms where large‐scale protein–protein interaction data is not available. Copyright © 2002 John Wiley & Sons, Ltd.
The tibial attachment of the anterior cruciate ligament in children and adolescents: analysis of magnetic resonance imaging
Authors: Shea Kevin G. , Apel Peter J. , Pfeiffer Ronald P. , Showalter Larry D. , Traughber Paul D. 
Published: August 2002

AbstractRecent studies have demonstrated that skeletally immature athletes with an ACL injury may require surgical reconstruction if they return to high‐demand sports. This study used MRI to compare the anatomy of the ACL in skeletally immature and adult subjects. Measurements were recorded in the sagittal plane for the anterior‐posterior dimension of the proximal tibia, and the anterior, center, and posterior limits of the ACL, and the roof inclination angle of the femur. These values were compared to established reference values for adult knee anatomy. In skeletally immature women (n=7) the ACL anterior limit, center and posterior limit, and roof inclination angle were 28%, 46%, 63%, and 38°, respectively, compared to 28%, 44%, 60%, and 35° in adult women. In skeletally immature men (n=15) the ACL anterior limit, center, posterior limit, and roof inclination angle were 27%, 43%, 59%, and 40°, respectively, compared to 28%, 44%, 59%, and 37° in adult men. In the younger subjects the overall dimensions of the proximal tibia were smaller than that in adults, but the anatomical landmarks for the ACL were proportional. If ACL reconstruction is performed in skeletally immature subjects, the smaller dimensions of the tibia need to be considered, and the use of anatomical landmarks is an important factor in graft placement
Incidence of Deep Venous Thrombosis in Patients Undergoing Obesity Surgery
Authors: Westling Agneta , Bergqvist David , Boström Annika , Karacagil Sadettin , Gustavsson Sven 
Published: August 2002

The aim of this study was to investigate prospectively the incidence of deep venous thrombosis (DVT) after surgery for morbid obesity. The series comprised 116 consecutive patients undergoing Roux‐en‐Y gastric bypass. The median age and body mass index were 35 years (range 19–59 years) and 42
kg/m2 (range 32–68 kg/m2), respectively. The patients were examined with duplex ultrasonography pre‐ and postoperatively. No patient had any symptoms or signs of DVT postoperatively, and ultrasonography showed no signs of thrombosis in iliac, femoral, and popliteal veins in any of the patients. Two patients (1.7%) had a thrombus in the peroneal vein of one leg.
Repeated ultrasonographic investigation after 1 week showed complete resolution of both. One patient with a previously unknown activated protein C resistance had an angiographically confirmed minor pulmonary embolus. The incidence of venous thromboembolism after obesity surgery seems to be low, and obesity as a risk factor for thromboembolic disease might have been overestimated in the past.
Bedside Percutaneous Tracheostomy: Prospective Evaluation of a Modification of the Current Technique in 100 Patients
Authors: Velmahos George C. , Gomez Hugo , Boicey Charles M. , Demetriades Demetrios 
Published: August 2002

AbstractPercutaneous dilatational tracheostomy (PDT) is being increasingly used. Concerns have been raised as to its safety, especially when it is done at the bedside. A prospective evaluation was conducted of 100 consecutive, unselected critically ill patients with PDT. The mean intensive care unit (ICU) stay before PDT was 12 days. One surgeon performed PDT alone (5 cases) or assisted residents (95 cases) in all operations; 84 were performed at the ICU bedside. Only the first six patients were taken to the operating room solely for tracheostomy. A modified technique was used: (1) the endotracheal tube was left in place during sequential dilations; (2) dilators were inserted in a 60‐degree cephalad orientation to the skin and directed caudally after penetration of the anterior tracheal wall; (3) a digit was inserted through the tracheal opening to guide withdrawal of the endotracheal tube to the level of the vocal cords; and (4) size 8 tracheostomy cannulas were inserted over 28F dilators. The average time from skin incision to insertion of the tracheostomy tube was 12 minutes (< 10 minutes, 41 patients; 10 to 15 minutes, 37 patients; > 15 minutes, 22 patients). Sixty‐five percent had unfavorable anatomic conditions due to spinal precautions or diffuse neck edema. Postoperative complications occurred in four patients; surgical emphysema after tracheal lacerations in three, cannula dislodgment in one. All complications were successfully managed without an operation by tube exchange (n= 3) or observation (n= 1); there was no procedure‐related mortality. Forty patients were available for long‐term follow‐up (6–18 months after tracheostomy) by telephone; one had persistent hoarseness without respiratory difficulty. We concluded that bedside PDT is safe and easy to teach when performed with a technique that ensures correct instrumentation.
Gastrointestinal Carcinoid Tumors: Long‐term Prognosis for Surgically Treated Patients
Authors: Söreide Jon Arne , van Heerden Jon A. , Thompson Geoffrey B. , Schleck Cathy , Ilstrup Duane M. , Churchward Marilyn 
Published: August 2002

AbstractTo evaluate long‐term survival of patients with gastrointestinal carcinoid tumors and to assess factors that may influence prognosis, 154 patients (49% females, 51% males), median age 62 years (range 12–84 years) treated at our institution during 1972–1982 have been followed long term. Tumor location included the foregut (7%), midgut (62%), and hindgut (30%). Ninety‐five percent of the patients underwent surgical or endoscopic excision of the primary tumor, with overall operative mortality and postoperative morbidity rates of 2.6% and 11%, respectively. At follow‐up, 60 patients (39%) were alive (median follow‐up 18 years; range 1–26 years). The main causes of death included carcinoid tumor burden (32%), unrelated causes (45%), other malignancy (19%), and unknown causes (4%). Observed overall 5‐ and 10‐year survivals were 69% and 53%, respectively. Survival was not related to gender or symptoms at presentation. However, age, embryologic origin, tumor size, depth of invasion, nodal status, and stage of disease proved to be of statistical significance (log‐rank). In a multivariate Cox' model, only older age (> 62 years) [P =0.001, odds ratio (OR) = 3.4) and embryologic origin (midgut versus foregut) (P = 0.045, OR = 0.45) provided independent prognostic power when death from any cause was taken as the end‐point. This study confirms that patient's age and the site of the primary tumor have prognostic significance. Carcinoid tumors are neuroendocrine tumors with a relatively good prognosis, and long‐term survival is possible despite advanced stages of disease.
Role of Malignancy and Preoperative Embolization in the Management of Carotid Body Tumors
Authors: Liapis Christos D. , Evangelidakis Emmanouil L. , Papavassiliou Vassilios G. , Kakisis John D. , Gougoulakis Alexandros G. , Polyzos Aristidis K. , Sechas Michael N. , Gogas John G. 
Published: August 2002

AbstractThe purpose of this retrospective study is to present our approach to the management of patients with carotid body tumors (CBTs), emphasizing the role of malignancy and preoperative embolization. Between 1975 and 1998 a series of 18 patients with CBTs were treated, and 16 of them underwent successful excision of the tumor. According to the Shamblin classification, six of the tumors were type I, six type II, and six type III. In three of these patients (two with type II tumors and one with type III) in whom preoperative embolization had been performed, mean intraoperative blood loss was 400 ml, whereas in the remaining 13 cases this loss was 700 ml. Two patients with intracranial tumor spread underwent only radiotherapy. Neither postoperative deaths nor strokes occurred. Temporary cranial nerve injury occurred in four cases (25%). Local lymph node invasion was found in two patients, establishing the diagnosis of malignancy. One of these patients developed distal metastases 3 years after the operation and was treated with radiotherapy and octreotide. Follow‐up ranging from 30 months to 23 years (mean 5 years) revealed no local recurrence except for the two patients who were treated with radiotherapy only. In conclusion, surgical excision remains the treatment of choice for CBTs and can be performed without major risks and with low morbidity and mortality. Preoperative embolization is helpful by diminishing intraoperative bleeding, and malignancy, though rare justifies early management.
Analysis of 100 Consecutive Hepatectomies: Risk Factors in Patients with Liver Cirrhosis or Obstructive Jaundice
Authors: Das Bidhan Chandra , Isaji Shuji , Kawarada Yoshifumi 
Published: August 2002

Abstract.We analyzed various pre‐, intra‐, and postoperative variables in 100 consecutive patients treated by hepatectomy for various malignant and benign liver diseases to identify patients at risk of developing postoperative complications. Patients were divided into three groups: those with normal liver (NL, n= 53); those with liver cirrhosis (LC, n= 32); and those with obstructive jaundice (OJ, n= 15). The overall postoperative morbidity and mortality rates were 14% and 4% (due to liver failure), respectively. In the LC group the combined presence of abnormal levels of serum hyaluronic acid (HA, > 200 ng/ml), indocyanine green retention rate at 15 minutes (ICGR15, > 15%), and hepatic uptake ratio of 99mTc‐galactosyl human serum albumin (GSA) at 15 minutes (LHL15, < 0.9) preoperatively was found to be a risk factor with a 100% morbidity rate. Operative blood loss of more than 1000 ml in LC patients was associated with high morbidity. In the OJ group preoperative parameters were almost normal after biliary drainage, but the extent of liver resection, blood loss > 2000 ml, and high serum interleukin‐6 12 hours after hepatectomy correlated with high postoperative morbidity. No morbidity or mortality was reported in the NL group, except in a single patient who received long‐term intraarterial chemotherapy preoperatively. Consequently, the extent of hepatectomy should be carefully determined according to the preoperative risk factors in LC patients; and in OJ patients hepatectomy, which tends to become extensive, should be carefully performed to minimize surgical stress because preoperative factors do not help predict outcome. Furthermore, the present study revealed that a serum HA level higher than 500 ng/ml on postoperative day 1 or day 7 (or both) was a useful marker for hepatic failure.