bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inactivation of the DNA repair gene O6‐methylguanine‐DNA methyltransferase by promoter hypermethylation and its relationship to aflatoxin B1‐DNA adducts and p53 mutation in hepatocellular carcinoma
Authors: Zhang Yu‐Jing , Chen Yu , Ahsan Habibul , Lunn Ruth M. , Lee Po‐Huang , Chen Chien‐Jen , Santella Regina M. 
Published: December 2002

AbstractO6‐methylguanine‐DNA methyltransferase (MGMT) is a repair protein that specifically removes promutagenic alkyl groups from the O6 position of guanine in DNA. MGMT is transcriptionally silenced by promoter hypermethylation in several human cancers. Methylation‐specific PCR (MSP) was used to analyze the MGMT promoter methylation status of 83 hepatocellular carcinomas (HCC) and 2 HCC cell lines (HepG2 and Hep3B). Hypermethylation was detected in 32 of 83 (39%) HCC tissues, but it was not found in either HCC cell line. We also analyzed MGMT expression by immunohistochemical analysis of HCC tissue samples. The presence of aberrant hypermethylation was associated with loss of MGMT protein. The relationship between methylation status and risk factors and tumor markers including environmental exposure to aflatoxin B1 (AFB1), measured as DNA adducts, and status of tumor suppressor gene p53 was also investigated. A statistically significant association was found between MGMT promoter hypermethylation and high level of AFB1‐DNA adducts in tumor tissues (OR = 5.05, 95% CI = 1.29–19.73). A significant association was also found between methylation and p53 mutation status (OR = 2.97, 95% CI = 1.09–8.11). These results suggest that epigenetic inactivation of MGMT plays an important role in the development of HCC and exposure to environmental carcinogens may be related to altered methylation of genes involved in cancer development. The role of chemical carcinogens in hypermethylation needs further investigation. © 2002 Wiley‐Liss, Inc.
Risk of melanoma among radiologic technologists in the United States
Authors: Freedman D. Michal , Sigurdson Alice , Rao R. Sowmya , Hauptmann Michael , Alexander Bruce , Mohan Aparna , Doody Michele Morin , Linet Martha S. 
Published: December 2002

AbstractOur study examines the risk of melanoma among medical radiation workers in the U.S. Radiologic Technologists (USRT) study. We evaluated 68,588 white radiologic technologists (78.8% female), certified during 1926–1982, who responded to a baseline questionnaire (1983–1989) and were free of cancer other than nonmelanoma skin at that time. Participants were followed through completion of a second questionnaire (1994–1998). We identified 207 cases, 193 subjects who reported first primary melanoma and 14 decedents with melanoma listed as an underlying or contributory cause of death. We examined risks of occupational radiation exposures using work history information on practices, procedures, and protective measures reported on the baseline questionnaire. Based on Cox proportional hazards regression, melanoma was significantly associated with established risk factors, including constitutional characteristics (skin tone, eye and hair color), personal history of nonmelanoma skin cancer, family history of melanoma and indicators of residential sunlight exposure. Melanoma risk was increased among those who first worked before 1950 (RR = 1.8, 95% CI = 0.6–5.5), particularly among those who worked 5 or more years before 1950 (RR = 2.4; 0.7–8.7; p (trend) for years worked before 1950 = 0.03), when radiation exposures were likely highest. Risk was also modestly elevated among technologists who did not customarily use a lead apron or shield when they first began working (RR = 1.4; 0.8–2.5). Clarifying the possible role of exposure to chronic ionizing radiation in melanoma is likely to require nested case‐control studies within occupational cohorts, such as this one, which will assess individual radiation doses, and detailed information about sun exposure, sunburn history and skin susceptibility characteristics. Published 2002 Wiley‐Liss, Inc.
Glypican‐3, overexpressed in hepatocellular carcinoma, modulates FGF2 and BMP‐7 signaling
Authors: Midorikawa Yutaka , Ishikawa Shumpei , Iwanari Hiroko , Imamura Takeshi , Sakamoto Hirohiko , Miyazono Kohei , Kodama Tatsuhiko , Makuuchi Masatoshi , Aburatani Hiroyuki 
Published: December 2002

AbstractThe Glypican (GPC) family is a prototypical member of the cell‐surface heparan sulfate proteoglycans (HSPGs). The HSPGs have been demonstrated to interact with growth factors, act as coreceptors and modulate growth factor activity. Here we show that based on oligonucleotide array analysis, GPC3 was upregulated in hepatocellular carcinoma (HCC). By northern blot analysis, GPC3 mRNA was found to be upregulated in 29 of 52 cases of HCC (55.7%). By Western blot analysis carried out with a monoclonal anti‐GPC3 antibody we generated, the GPC3 protein was found to be overexpressed in 6 hepatoma cell lines, HepG2, Hep3B, HT17, HuH6, HuH7 and PLC/PRF/5, as well as 22 tumors (42.3%). To investigate the role of overexpressed GPC3 in liver cancer, we analyzed its effects on cell growth of hepatoblastoma‐derived cells. Overexpression of GPC3 modulated cell proliferation by inhibiting fibroblast growth factor 2 (FGF2) and bone morphogenetic protein 7 (BMP‐7) activity. An interaction of GPC3 and FGF2 was revealed by co‐immunoprecipitation, while GPC3 was found to inhibit BMP‐7 signaling through the Smad pathway by reporter gene assay. The modulation of growth factors by GPC3 may help explain its role in liver carcinogenesis. In addition, the ability of HCC cells to express GPC3 at high levels may serve as a new tumor marker for HCC. © 2002 Wiley‐Liss, Inc.
Neuroblastoma trends in Osaka, Japan, and Great Britain 1970–1994, in relation to screening
Authors: Honjo Satoshi , Doran Helen E. , Stiller Charles A. , Ajiki Wakiko , Tsukuma Hideaki , Oshima Akira , Coleman Michel P. 
Published: December 2002

AbstractJapan pioneered and has maintained a nationwide mass screening programme for neuroblastoma since 1985 without prior evaluation among a target population. Convincing population‐based evaluation of the ongoing programme has also been very limited because a population‐based registry for childhood cancer has not been in operation. This report describes trends in incidence of and mortality from neuroblastoma in Osaka Prefecture, Japan, using Great Britain as an external control, between 1970 and 1994. Incidence and mortality rates were comparable between the 2 areas before the beginning of screening in Osaka. However, incidence rates were markedly increased in Osaka, especially among children younger than 1 year, from 25.9 per million children during 1970–1979 to 240.2 during 1991–1994, while age‐standardized incidence rates for metastatic tumours among children aged 1 year or above did not decrease after introduction of the programme. Age‐standardized mortality rates per million were unchanged at 3.9 (1970–1979) and 4.1 (1991–1994) in Osaka and 5.7 (1971–1979) and 5.0 (1991–1994) in Great Britain. Cumulative incidence rates among those up to 15 years old progressively increased from 103.4 per million (1970–1979) to 350.0 (1991–1994) in Osaka, though cumulative mortality rates did not decrease: 52.0 and 57.5, respectively. Corresponding figures in Great Britain were 101.0, 115.1, 78.6 and 70.1, respectively. The present findings show little beneficial effect of the screening programme. © 2002 Wiley‐Liss, Inc.
Echocardiographic diagnosis and follow‐up of left ventricular pseudoaneurysm complicating bacterial pericarditis
Authors: Deng You‐Bin , Chang Qing , Xiang Hui‐Juan , Li Chun‐Lei 
Published: December 2002

AbstractTwo‐dimensional echocardiography demonstrated a pseudoaneurysm of the lateral wall of the left ventricle in a 13‐year‐old girl with bacterial pericarditis. The echocardiographic findings included a 5‐mm discontinuity in the lateral wall of the left ventricle, an associated anechoic collection (5.6 × 5.1 cm), and a narrow communication between the left ventricle and the anechoic collection. Color Doppler imaging demonstrated flow through the communication between the left ventricle and the aneurysmal cavity. The patient and her family refused surgery. A follow‐up echocardiographic examination more than 6 years later demonstrated disappearance of the discontinuity of the left ventricular lateral wall, no flow between the left ventricle and the pseudoaneurysm, and thrombus formation within the pseudoaneurysm. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:48–50, 2003
Tuberculous ileitis in a renal transplant recipient with familial Mediterranean fever: Gray‐scale and power Doppler sonographic findings
Authors: Yilmaz Erkan , Balci Ali , Sal Selma , Cakmakci Handan 
Published: December 2002

AbstractThe ileocecal area is the most common site of involvement of intestinal tuberculosis. We report the case of a 26‐year‐old renal transplant recipient with familial Mediterranean fever who developed tuberculous ileitis. Gray‐scale sonography and CT showed circumferential thickening of the bowel wall and enlargement of the mesenteric lymph nodes. Power Doppler sonography revealed markedly increased vascularity in the wall of the affected ileal segment and in the mesenteric nodes. Some nodes had no flow at the center owing to caseation necrosis, a finding consistent with the diagnosis of tuberculous ileitis. Colonoscopy was performed, and histopathologic examination of biopsy specimens revealed acute inflammatory changes. Cultures of the specimens confirmed the presence of Mycobacterium tuberculosis. We conclude that findings on power Doppler sonography may support a diagnosis of tuberculous ileitis and avoid clinical mismanagement. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:51–54, 2003
Posterior mediastinal arteriovenous malformation with atypical color Doppler sonographic findings
Authors: Cheng Shih‐Lung , Wang Hao‐Chien , Yang Pan‐Chyr 
Published: December 2002

AbstractAn arteriovenous malformation (AVM) is an anomaly of capillary development that results in a direct connection between branches of an artery and veins, with no intervening capillary network. A definite diagnosis of AVM is usually made with angiography. We report the case of a posterior mediastinal AVM found on routine sonography in a 64‐year‐old woman with neglected hypertension and severe back pain. Color Doppler imaging showed 2 adjoined vascular structures without a typical mosaic‐like flow pattern, and spectral Doppler analysis showed low‐resistance flow and arteriovenous shunting in 2 adjoined vascular structures. The diagnosis was subsequently confirmed by angiography. Because disastrous bleeding could result if needle biopsy were performed inadvertently in the case of a suspected mediastinal AVM, we suggest that color Doppler sonography be attempted if there is an adequate acoustic window. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:44–47, 2003
Five‐year follow‐up of placental involution after abdominal pregnancy
Authors: Valenzano Mario , Nicoletti Luca , Odicino Franco , Cocuccio Silvia , Lorenzi Paola , Ragni Nicola 
Published: December 2002

AbstractA 29‐year‐old woman with an abdominal pregnancy was admitted to the hospital at 29 weeks' menstrual age. At 30 weeks, laparotomy was performed, and a live fetus, wrapped in membrane remnants, was taken from the abdominal cavity. The placenta, inserted in the right hemipelvis, was left in situ. The patient's postoperative recovery was uneventful, and she was monitored periodically as follow‐up. At her 5‐year follow‐up visit, we assessed placental involution by measuring serum β human chorionic gonadotropin and by using color and pulsed Doppler sonography. The dynamics of the regression of placental volume yielded a bimodal curve: a phase of decrease over the first 2 months, coincident with a reduction in vascularization, followed by stability that lasted 6–8 months, and a second phase of gradual volume reduction. At 5 years, the placenta appeared as a small residual echogenic mass with no vascularity. The use of MRI in this case provided no additional information to what we found using sonography. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:39–43, 2003
Sonographic grading of fetal intracardiac echogenic foci in a population at low risk of aneuploidy
Authors: Wax Joseph R. , Cartin Angelina , Pinette Michael G. , Blackstone Jacquelyn , Michaud Janet , Byers Susan , Boutin Nancy 
Published: December 2002

AbstractPurposeWe screened pregnant women at low risk of a fetal chromosomal abnormality for the presence of fetal intracardiac echogenic foci (ICEF) and graded those foci by using sonographic gain reduction. Our objectives were to determine the interobserver reliability of the technique and the association of ICEF, by grade, with fetal aneuploidy.MethodsPregnant women who were 18–35 years old, at low risk for fetal chromosomal abnormalities, and referred for targeted sonography at 16–24 weeks' menstrual age were eligible to participate. All patients whose fetuses had ICEF were offered fetal chromosomal analysis. The presence of ICEF was ascertained by an apical 4‐chamber view of the fetal heart and graded independently by 2 examiners blinded to each other's assessment. Grading was based on the difference in echogenicity of the ICEF and the thoracic spine as the ultrasound gain was reduced; in grade 1, the ICEF image was lost before that of the thoracic spine; in grade 2, the ICEF and thoracic spine images disappeared at the same gain setting; and in grade 3, the thoracic spine image was lost before that of the ICEF.ResultsDuring the 6‐month study period, 383 eligible women were examined, and ICEF were seen in 35 fetuses (9.1%): 25 (71.4%) in the left ventricle, 1 (2.9%) in the right ventricle, and 9 (25.7%) in both ventricles. ICEF grading was successfully performed in all 33 of the women with fetal ICEF who elected to participate. Twenty‐one (63.6%) had grade 1, 9 (27.3%) had grade 2, and 3 (9.1%) had grade 3 ICEF. Interobserver agreement was noted in 27 (90.0%) of 30 available paired second‐trimester observations (kappa = 0.8), indicating excellent agreement. Two fetuses (6.1%) with grade 1 ICEF but no other risk factors for aneuploidy had chromosomal abnormalities, as compared with 1 fetus (0.3%) in the control group, which had no ICEF (p = 0.02).ConclusionsSonographic grading of ICEF is feasible and reliable. The presence of fetal ICEF in a population otherwise at low risk for aneuploidy seems to warrant the performance of fetal chromosomal analysis. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:31–38, 2003
Three‐dimensional sonographic evaluation of the infant spine: Preliminary findings
Authors: Hughes Jacqueline A. , De Bruyn Rose , Patel Kalpana , Langford Sarah‐Jane , Thompson Dominic 
Published: December 2002

AbstractPurposeThe aims of this study were to evaluate normal spinal anatomy in neonates and infants as seen by 3‐dimensional sonography (3D US), to determine the value of 3D US in the evaluation of occult spinal dysraphia in infants, and to correlate the findings of 3D US with those of 2‐dimensional sonography (2D US) and MRI, when available.MethodsWe used 2D US and 3D US to examine the lumbosacral spine in infants with cutaneous stigmata, syndromes associated with spinal dysraphia, and abnormal radiographs. We also evaluated, as controls, healthy infants who had no markers of spinal abnormality. 2D sonograms, 3D sonograms, radiographs, and MRI scans, when available, were compared to assess differences in the display of the infant spine.ResultsIn total, we examined 29 infants: 18 subjects and 11 control infants. The correlation between 2D US and 3D US was 100% in the detection of congenital defects of the spinal cord, although 3D US allowed superior visualization of the vertebral bodies and posterior spinal elements. When a gross abnormality of the posterior spinal elements occurred with pathologic overlying soft tissue, interpretation was simpler with MRI than with sonography.Conclusions3D US is a useful adjunct to 2D US when screening the infant spine for congenital defects, particularly in showing alignment of posterior spinal elements and integrity of vertebral bodies. This ability is important because posterior spinal defects may be associated with underlying spinal cord abnormalities. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:9–20, 2003
Sonographic assessment of changes in thickness of different abdominal fat layers in response to diet in obese women
Authors: Sabir Nuran , Pakdemirli Emre , Sermez Yurdaer , Zencir Mehmet , Kazil Selcuk 
Published: December 2002

AbstractPurposeWe evaluated the potential application of sonography to monitor alterations in abdominal fat thickness in obese women before and after dieting.MethodsThis study included 40 obese women (mean age, 42.2 ± 9.4 years; mean body mass index [BMI], 36.0 ± 5.9 kg/m2) who underwent a 3‐month low‐calorie diet. Height, weight, waist circumference (WC), and hip circumference (HC) were measured. BMI and waist‐to‐hip ratio (WHR) were calculated. Abdominal subcutaneous (S) and intra‐abdominal preperitoneal (P) fat were measured at their maximum (max) and minimum (min) thickness sites using a 7.5‐MHz linear‐array probe. Intra‐abdominal visceral (V) fat was measured using a 3.5‐MHz convex‐array probe. Measurements were taken before and after caloric restriction.ResultsThe mean weight was reduced from 88.6 ± 17.1 kg to 83.0 ± 15.9 kg (p < 0.0001). The mean changes in Smin (r = 0.376, p = 0.017), Smax (r = 0.508, (p = 0.001), Pmin (r = 0.439, p = 0.005), and V (r = 0.365, p = 0.022) fat thicknesses were positively correlated with change in weight; the change in Pmax fat thickness showed the best and most significant correlation (r = 0.591, p < 0.0001). BMI (r = 0.969, p < 0.0001), WC (r = 0.510, p = 0.001), and HC (r = 0.422, p = 0.007) changes were also positively correlated with weight change, but the WHR change (r = 0.019, p > 0.05) was not.ConclusionsAll the abdominal fat layers, particularly the intra‐abdominal P fat, will decrease in response to loss of body fat by dieting. Sonography seems to be useful in monitoring small variations in the thicknesses of abdominal S and intra‐abdominal P and V fat. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:26–30, 2003
Cystic appearance of cervical lymph nodes is characteristic of metastatic papillary thyroid carcinoma
Authors: Kessler Ada , Rappaport Yoram , Blank Annat , Marmor Sylvia , Weiss Judith , Graif Moshe 
Published: December 2002

AbstractPurposeThe usefulness of high‐resolution sonography in diagnosing cervical lymph node metastases from papillary thyroid carcinoma was investigated. The accuracy of a particular sign, cystic change within a node, in establishing the diagnosis was assessed.MethodsThe sonographic findings in 63 patients with enlarged cervical lymph nodes were retrospectively reviewed. The patients had undergone high‐resolution gray‐scale and color Doppler sonography followed by ultrasound‐guided fine‐needle aspiration (FNA) in all patients and surgical excision in 27 patients.ResultsAbnormal sonographic features were present in the lymph nodes of all 63 patients. In 14 (70%) of 20 patients with papillary thyroid carcinoma, sonography depicted cystic changes. This pattern was not found in any of the other 43 patients, in whom FNA revealed either metastasis from another malignancy (22 patients) or benign reactive lymphadenopathy (21 patients). Among the 63 patients, there were 43 true‐negative, 14 true‐positive, 6 false‐negative, and no false‐positive results in the diagnosis of metastatic papillary thyroid carcinoma using the presence or absence of an intranodal cystic area on sonography. These results yielded a 70% sensitivity, 100% specificity, 100% positive predictive value, 88% negative predictive value, and 90% overall accuracy for this criterion.ConclusionsCystic changes within a cervical lymph node are highly suggestive of metastatic papillary thyroid carcinoma. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:21–25, 2003
Effect of transvaginal sonography on the use of invasive procedures for evaluating patients with a clinical diagnosis of ectopic pregnancy
Authors: Atri Mostafa , Valenti David A. , Bret Patrice M. , Gillett Peter 
Published: December 2002

AbstractPurposeOur purpose was to determine the effect of transvaginal sonography (TVS) on the diagnostic evaluation of patients with suspected ectopic pregnancy (EP). Specifically, we wished to determine what effect TVS had on the use of invasive procedures.MethodsThis was a retrospective review of the medical records of 290 patients with a surgically documented diagnosis of EP. It included 147 consecutive patients from the era of use of suprapubic sonography (SPS) (1982–1987) and 143 consecutive patients from the era of use of TVS (1987–1995). We compared the percentages of patients who had undergone sonographic examinations, the rates of use of the invasive procedures dilatation and curettage (D&C) and diagnostic laparoscopy (DL), time from presentation to diagnosis, necessity for transfusion, status of EP at surgery, and various other characteristics of the patients (eg, demographics, serum level of β human chorionic gonadotropin, and presenting symptoms).ResultsIn the SPS era, 46.9% of the patients had undergone sonography, compared with 78.3% in the TVS era (p = 0.001). Sonographic sensitivity was 60.9% in the SPS era and 93.8% in the TVS era (p = 0.001). D&C was performed in 53.1% and DL in 76.2% of patients in the SPS era, compared with 14.0% and 30.8%, respectively, in the TVS era (p = 0.001). In the last full year of the study, only 9% of the patients had undergone D&C and 9%, DL. The overall time from presentation to diagnosis significantly decreased from 45.6 hours in the SPS era to 16.8 hours in the TVS era (p = 0.002). We found no significant difference between the 2 eras in the need for transfusion and the percentage of ruptured EPs at surgery (p > 0.05).ConclusionsThe introduction of TVS has had an important effect on the evaluation of patients with EP by nearly eliminating the need for D&C and DL and permitting clinicians to take a more conservative approach to managing EP. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 31:1–8, 2003
Fully automated high yield synthesis of (R)‐ and (S)‐[11C]verapamil for measuring P‐glycoprotein function with positron emission tomography
Authors: Luurtsema Gert , Windhorst Albert D. , Mooijer Martien P.J. , Herscheid Jacobus D.M. , Lammertsma Adriaan A. , Franssen Eric J.F. 
Published: December 2002

AbstractRacemic (±) verapamil is a well characterized substrate for P‐glycoprotein (P‐gp). However, the in vivo pharmacokinetics and pharmacodynamics of both enantiomers are reported to be different. In the preparation of evaluation studies of both enantiomers in animals and humans, the purpose of the present study was to optimize and automate the synthesis of (R)‐ and (S)‐[11C]verapamil.(R)‐ and (S)‐[11C]verapamil were prepared from (R)‐ and (S)‐desmethyl‐verapamil, respectively, by methylation with no‐carrier added [11C]methyliodide or [11C]methyltriflate. Different conditions of the methylation reaction were studied: reaction time, temperature, base and solvent, and chemical form of the precursor using either the hydrochloric acid salt or the free base of the starting material. After optimization, the synthesis was fully automated using home‐made modules and performed according to GMP guidelines. Optimal yields of 60–70% for the methylation reaction were obtained using 1.5 mg of the free base of (R)‐ or (S)‐desmethyl‐verapamil in 0.5 ml of acetonitrile at 50°C for 5 min with [11C]methyltriflate as methylating agent. Under the same reaction conditions, but with a reaction temperature of 100°C, the radiochemical yield starting with [11C]methyliodide as methylation reagent was 40%. The specific activity of (R)‐ and (S)‐[11C]verapamil was >20 GBq/μmol and the radiochemical purity was >99% for both methods. The total synthesis time was 45 min. The automated high yield synthesis of (R)‐ and (S)‐[11C]verapamil provides the means for evaluating both enantiomers as in vivo tracers of P‐gp function. Copyright © 2002 John Wiley & Sons, Ltd.