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991.
Increased body iron stores in elite road cyclists 总被引:8,自引:0,他引:8
Deugnier Y Loréal O Carré F Duvallet A Zoulim F Vinel JP Paris JC Blaison D Moirand R Turlin B Gandon Y David V Mégret A Guinot M 《Medicine and science in sports and exercise》2002,34(5):876-880
BACKGROUND: One third of French elite road cyclists were found to have hyperferritinemia on antidoping control tests performed during the Tour de France in 1998. PURPOSE: This study was undertaken to determine whether hyperferritinemia corresponded to elevated body iron stores or not and, affirmatively, what were its mechanism, its clinical consequences, and its spontaneous course. METHODS: 83 elite road male cyclists presenting with hyperferritinemia, defined as serum ferritin level greater than 300 microg.L-1, were studied with respect to consumption of iron and other drugs, serum iron tests, HFE mutations, and hepatic iron concentration (HIC; N < 35 micromol.g-1 dry weight). RESULTS: All cyclists were asymptomatic and had normal physical and cardiac examination. Their median (range) serum ferritin, serum iron, and transferrin saturation levels were 504 microg.L-1 (306-1671), 20 micromol.L-1 (8.5-36.3), and 39% (20-76), respectively. HIC was increased in 24/27 up to 187 micromol.g-1. Allelic frequency of the H63D mutation was increased in cyclists when compared to controls (P = 0.04). However, iron tests did not differ according to HFE genotypes. Most cyclists (89%) had been supplemented with iron. The median iron supplementation was 25.5 g (range: 1.4-336) and correlated well (P = 0.002) with serum ferritin. Evolution of serum ferritin levels did not differ whether cyclists had been continuing iron supplementation or not. CONCLUSION: Hyperferritinemia in elite road cyclists accounted for increased body iron stores caused by and persisting after cessation of excessive iron supplementation. Even when mild, iron excess may expose to long-term complications and should be removed, at least at the time when professional cyclists retire. To prevent iatrogenic iron overload, supplementation with iron must be done according to serum ferritin follow-up and not either blindly or on the basis of serum iron determination only. 相似文献
992.
Several neurotransmitter systems have been related to developmental processes during the past decade. In this review, we discuss the evidence that the nicotinic acetylcholine receptors could have an additional function during development that may be unrelated to their role in cholinergic neurotransmission in the vertebrate brain. Both temporal expression data and in vitro and in vivo studies with nicotinic agonists and antagonists have provided direct support for a role of nicotinic receptors in neural developmental processes such as neurite outgrowth and differentiation. A similar picture has emerged for other neurotransmitter and receptor systems as well, which generates a new view of neural processes during both development and mature life. 相似文献
993.
Chelala E Paraskevas N Chahidi N Poortmans M André R Allé JL 《Acta chirurgica Belgica》2002,102(1):30-32
From May 91 to March 99 a consecutive series of 100 acute obstructions or perforations of the left colon or rectum were treated by primary resection with mechanical anastomosis using a double or triple stapling technique without proximal colostomy. There were 8 postoperative deaths (8%) due to sepsis, acute respiratory distress syndrome, pulmonary embolism, stroke, and cachexy. Complications occurred in 29% of surviving patients. Clinical anastomotic leaks were observed in 7%, respiratory infection in 8%, wound infection in 8% and major cardiovascular problems in 4% of patients. The median hospital stay was 19 days. The morbidity and mortality of this series did not exceed the cumulative morbidity and mortality that can be expected after staged surgery. Compared with staged surgery, immediate resection and anastomosis using an entirely mechanical suture, thereby avoiding the problems of colostomy and reducing the length of hospital stay, has significant advantages for patients. 相似文献
994.
BACKGROUND: The use of selective neck dissection in a positive neck is still controversial. The object of this study was to ascertain the possibility of doing this procedure in oral cavity carcinoma with a single clinically metastatic lymph node smaller than 6 cm (N1 and N2a). PATIENTS AND METHODS: From 1970 to 1994, we analyzed 164 oral cavity cancer patients with clinically N1 or N2a stage cancer submitted to radical neck dissection. RESULTS: The histologic findings did not confirm a metastatic lymph node in 69 (42.1%) cases (pN0) and showed multiple lymph nodes in 19 (11.6%) cases. Moreover, just one patient (0.6%) had a metastatic lymph node at level IV (one case with multiple lymph nodes) and none at level V. CONCLUSIONS: Because we did not find a single metastatic lymph node at levels IV and V and there was a high incidence of pN0 (57.4%) in patients with clinical N1 stage at level I, these patients could be candidates for a supraomohyoid neck dissection (extended or not to level IV) instead of radical neck dissection. 相似文献
995.
Analysis of estrogen receptor polymorphism in codon 325 by PCR-SSCP in breast cancer: association with lymph node metastasis 总被引:13,自引:0,他引:13
Vasconcelos A Medeiros R Veiga I Pereira D Carrilho S Palmeira C Azevedo C Lopes CS 《The breast journal》2002,8(4):226-229
Breast cancer is the most frequent neoplasm in women. Expression of the estrogen receptor (ER) has a key role in breast cancer; the ER gene is located at chromosome 6q24-q27 and is made up of 8 exons with a total of 140 kb. The polymorphism in codon 325 of exon 4 (ER325) is a transition CCC→CCG. The objective of this study is to analyze the frequency of this polymorphism in breast cancer using the polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) technology. DNA was extracted from tumor cells of 70 breast cancer patients and from the peripheral blood of 69 individuals without any known pathology (control group). Amplification products of the ER gene were analyzed by SSCP. In breast cancer patients the ER325 polymorphism was detected in 42.8% of the cases. In contrast, in the control group, the frequency of the same polymorphism was 24.6. Statistical comparison of the frequency distributions revealed that they are significantly different ( p = 0.023). There was also an association between ER325 polymorphism and the absence of lymph node metastases ( p = 0.038). Our data suggest that there is a relationship between the ER325 polymorphism and susceptibility to breast cancer (OR = 2.3; 1.10 < OR < 5.1) and that it can also be related with the metastasization process. 相似文献
996.
Sánchez J Rosado R Ramírez D Medina P Mezquita S Gallardo A 《Surgical laparoscopy, endoscopy & percutaneous techniques》2002,12(6):443-445
Four new cases of necrosis of the omentum secondary to torsion are reported. We review the associated signs and symptoms, which are usually those of an acute inflammatory condition in the right lower quadrant (RLQ), very similar to acute appendicitis. Because of acute abdominal pain in the RLQ, along with an uncertain diagnosis, laparoscopic surgery was performed in these cases. Laparoscopy demonstrated the existence of the omental infarction and allowed for complete treatment of the condition without the need for laparotomy. 相似文献
997.
David Courtin Laurent Argiro Vincent Jamonneau Louis N'dri Paul N'guessan Laurent Abel Alain Dessein Michel Cot Claude Laveissiere André Garcia 《Infection, genetics and evolution》2006,6(2):123-129
This study aimed to determine whether single nucleotide polymorphisms (SNPs) within tumour necrosis factor-alpha (TNF) and interleukin-10 (IL10) promoters and genes are associated with human African trypanosomiasis (HAT). The polymorphisms used in the analysis were TNF(-308G/A), TNF(-238G/A), TNF(-1031T/C), TNF(+488G/A), IL10(-1082G/A) and IL10(-592C/A). A familial case-control sample of 277 individuals (102 cases and 175 parents) and a matched case-control group of 225 subjects (88 cases and 137 unrelated controls) were gathered together in this study. A conditional logistic regression was used to test for association. We carried out this analysis in the overall population and after stratification by time of exposure, age and ethnic group. Our results show that in the overall population, and after stratification by time of exposure, the IL10(-592A) allele is associated with a lower risk of disease, suggesting the possibility of a protective effect. After stratification by time of exposure, individuals homozygous for the SNP located in the TNF(-308) promoter were shown to present a higher risk of developing the disease early after exposure. Our study shows that TNF(-308G/A) and IL10(-592C/A) SNPs are polymorphisms of interest in the investigation of the genetic susceptibility to human African trypanosomiasis. Larger studies are currently underway to confirm these results. 相似文献
998.
Maria C B Tognim Ana C Gales Andréia P Penteado Suzane Silbert Hélio S Sader 《Infection control and hospital epidemiology》2006,27(7):742-747
OBJECTIVE: To evaluate the emergence and dissemination of metallo- beta -lactamase (MBL)-producing Acinetobacter species. DESIGN: All carbapenem-resistant Acinetobacter strains (1 strain per patient) collected during the period 1993-2001 were evaluated. SETTING: A Brazilian tertiary care teaching hospital (Hospital Sao Paulo, Sao Paulo). METHODS: Seventy-three strains of carbapenem-resistant Acinetobacter species were recovered from the organism bank of the hospital. All isolates were tested for antimicrobial susceptibility by broth microdilution methods, and the production of MBL was initially assessed by phenotypic tests (MBL Etest strip and a disk approximation test). The MBL enzymes were identified by polymerase chain reaction using primers for bla(IMP), bla(VIM), and bla(SPM), followed by gene sequencing. Genetic similarity among the carbapenem-resistant strains was evaluated by automated ribotyping. RESULTS: Only colistin and ampicillin-sulbactam showed reasonable in vitro activity against carbapenem-resistant isolates (97% and 74% of isolates susceptible, respectively). More than half of the isolates (55%) had a positive MBL phenotypic test result and a positive polymerase chain reaction result for bla(IMP-1). The proportion of IMP-1-producing Acinetobacter isolates among carbapenem-resistant strains increased from 0% in the 1993-1997 period to 29% in 1998 and 100% in the 1999-2001 period. No carbapenem-resistant Acinetobacter isolates that harbored bla(VIM) or bla(SPM) were detected. Molecular typing results revealed 20 ribogroups among carbapenem-resistant isolates. During the study period of 1994-2001, we identified 2 major ribogroups, 52-1 (MBL-negative and MBL-positive strains) and 60-7 (MBL-positive strains), that had a coefficient of similarity of 0.85 or higher. CONCLUSIONS: Our results indicate that IMP-1-producing strains of Acinetobacter emerged in our institution in 1998. Since then, production of this MBL was detected not only in the major ribogroups of carbapenem-resistant Acinetobacter species but also among isolates that belonged to 17 distinct ribogroups, indicating that this important mechanism of antimicrobial resistance was disseminated among distinct clones. 相似文献
999.