Note: This page contains sample records for the topic a1298c mtr a2756g from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: August 15, 2014.
1

Methionine synthase A2756G and methylenetetrahydrofolate reductase A1298C polymorphisms are not risk factors for idiopathic venous thromboembolism.  

PubMed

Hyperhomocysteinemia is a defined risk factor for venous thromboembolism (VTE). Several polymorphisms of genes encoding for enzymes acting in the remethylation pathway of homocysteine metabolism, ie, methionine synthase (MS) A2756G, methylenetetrahydrofolate reductase (MTHFR) C677T and MTHFR A1298C, can cause increased homocysteine levels particularly in patients with deficiencies of folic acid, vitamin B6, or B12 and hence be potential risk factors for VTE. Indeed, homozygous MTHFR C677T was shown to be a mild risk factor for VTE by some, but not by all, investigators. In this study, we assessed the risk exerted by MS A2756G and MTHFR A1298C in a cohort of patients with idiopathic venous thromboembolism. Homozygosities for MS A2756G and MTHFR A1298C were not found to be statistically significant risk factors for VTE. In addition, no interactions were observed among MS A2756G, MTHFR A1298C and MTHFR C677T in conferring a risk of VTE. PMID:11920232

Salomon, O; Rosenberg, N; Zivelin, A; Steinberg, D M; Kornbrot, N; Dardik, R; Inbal, A; Seligsohn, U

2001-01-01

2

Association between MTR A2756G polymorphism and childhood acute lymphoblastic leukemia: a meta-analysis.  

PubMed

Abstract To date, many studies on the association between methionine synthase (MTR) A2756G and childhood acute lymphoblastic leukemia (ALL) have provided either controversial or inconclusive results. To clarify the effect of MTR A2756G on the risk of childhood acute lymphoblastic leukemia, a meta-analysis of all relevant studies was performed. The fixed effects model showed that the 2756A allele was associated with a decreased risk of childhood ALL compared with the G allele (ORA vs. G = 0.872; 95% CI 0.782-0.974; p = 0.015, I(2) = 46.9%). Additionally, when comparing subjects with ALL and controls with AA vs. AG or AA vs. AG + GG (dominant model), significant differences were found in the fixed effects model (ORAA vs. AG = 0.869; 95% CI 0.760-0.994; p = 0.040, I(2) = 26.4%; ORAA vs. AG+ GG = 0.858; 95% CI 0.754-0.976; p = 0.020, I(2) = 39.6%). In a subgroup analysis in a population with the same background, individuals with the AA genotype had a reduced risk of developing ALL compared to individuals with the AG genotype. In conclusion, our study provides evidence suggesting that MTR A2756G is associated with a reduced risk of developing childhood ALL. PMID:23906019

Xia, Jia; Wang, Yadan; Zhang, Hang; Hu, Yu

2014-06-01

3

Role of polymorphism of methyltetrahydrofolate-homocysteine methyltransferase (MTR) A2756G and breast cancer risk.  

PubMed

Breast cancer (BC) is one of the most common causes of death among women, and second in Iran. The objectives of this study were to determine the frequency of methyltetrahydrofolate-homocysteine methyltransferase (MTR) 2756 gene polymorphism in patients with breast cancer. For the first time, we evaluated these polymorphisms and effects on the breast cancer risk association in an Iranian sporadic population-based case-control study of 282 breast cancer cases and 310 controls using a PCR-RFLP-based assay. Analyses of affected and controls show that homozygote genotype MTR 2756 AA has the highest frequency in both groups (33.3 in patients). Genotype MTR 2756 GG was the highest risk factor in our population [AG/GG odds ratio, 0.329 (95% CI: 0.146-0.741) p = 0.006, AA/AG, OR, 2.316, 95% CI: 1.509-3.555, p = 0.001, AA/GG odds ratio, 0.761 (95% CI: 0.363-1.595) p = 0.297]. There was a significant association of breast cancer risk with MTR 2756 GG and AA polymorphism. PMID:24166605

Hosseini, Mojgan

2013-10-01

4

Methionine synthase A2756G polymorphism and breast cancer risk: an up-to-date meta-analysis.  

PubMed

The methionine synthase (MTR) gene polymorphism A2756G has been linked to the risk of developing breast cancer, but the available results were inconsistent and underpowered. To derive a more precise estimation of the association between A2756G and breast cancer risk, an updated meta-analysis of 16 available studies with 9866 cases and 11,702 controls estimating the association between MTR A2756G and breast cancer risk was conducted. The quality of these studies was generally good except 2 studies with a lowest score 4 according to the Newcastle-Ottawa Scale (NOS). The results suggested that there is no significant association between A2756G and breast cancer risk in overall results. In the stratified analysis by ethnicity, source of controls (population or hospital-based), Hardy-Weinberg equilibrium (HWE) in controls, sample size (?1000 and <1000 subjects), and menopausal status, the 2756G allele was associated with a decreased risk in Caucasians, PB (population-based) subgroup, and large studies. But the associations disappeared after removing the studies not in HWE. On the contrary, an increased risk was found in small studies. In conclusion, the findings suggest that MTR A2756G polymorphism is not associated with altered susceptibility to breast cancer, while the observed decreased risk in Caucasians, PB subgroup, and large studies and increased risk in small studies may be due to selection bias or other unknown factors. PMID:23845785

Zhong, Shanliang; Xu, Jinjin; Li, Wenjing; Chen, Zhiyuan; Ma, Tengfei; Zhao, Jianhua

2013-09-25

5

Methionine synthase A2756G polymorphism and risk of colorectal adenoma and cancer: evidence based on 27 studies.  

PubMed

Methionine synthase (MTR), which plays a central role in maintaining adequate intracellular folate, methionine and normal homocysteine concentrations, was thought to be involved in the development of colorectal cancer (CRC) and colorectal adenoma (CRA) by affecting DNA methylation. However, studies on the association between MTR A2756G polymorphism and CRC/CRA remain conflicting. We conducted a meta-analysis of 27 studies, including 13465 cases and 20430 controls for CRC, and 4844 cases and 11743 controls for CRA. Potential sources of heterogeneity and publication bias were also systematically explored. Overall, the summary odds ratio of G variant for CRC was 1.03 (95% CI: 0.96-1.09) and 1.05 (95% CI: 0.99-1.12) for CRA. No significant results were observed in heterozygous and homozygous when compared with wild genotype for these polymorphisms. In the stratified analyses according to ethnicity, source of controls, sample size, sex, and tumor site, no evidence of any gene-disease association was obtained. Results from the meta-analysis of four studies on MTR stratified according to smoking and alcohol drinking status showed an increased CRC risk in heavy smokers (OR?=?2.06, 95% CI: 1.32-3.20) and heavy drinkers (OR?=?2.00, 95% CI: 1.28-3.09) for G allele carriers. This meta-analysis suggests that the MTR A2756G polymorphism is not associated with CRC/CRA susceptibility and that gene-environment interaction may exist. PMID:23593229

Ding, Weixing; Zhou, Dong-Lei; Jiang, Xun; Lu, Lie-Sheng

2013-01-01

6

Cerebral sinovenous thrombosis associated with MTHFR A1298C mutation in the newborn: a case report.  

PubMed

Although cerebral sinovenous thrombosis (CSVT) is a rare condition in the neonatal period, high rates of morbidity and mortality necessitate the establishment of an early diagnosis. Methylenetetrahydrofolate reductase (MTHFR) plays a central role in the folate cycle and mutations of MTHFR are associated with vascular disease. While the C677T common missense mutation is the most well-defined MTHFR polymorphism, another common missense mutation, A1298C also exists. There has been no reported case of CSVT associated with MTHFR A1298C mutation in the neonatal period. Herein, we report a neonate with CSVT who was found to have MTHFR A1298C homozygosity. PMID:22797907

Cizmeci, Mehmet Nevzat; Kanburoglu, Mehmet Kenan; Akelma, Ahmet Zulfikar; Donmez, Ahsen; Sonmez, Fatma Mujgan; Polat, Aziz; Kosehan, Dilek; Tatli, Mustafa Mansur

2013-02-01

7

Role of methylenetetrahydrofolate reductase A1298C polymorphism in cerebral venous thrombosis.  

PubMed

The association between the methylenetetrahydrofolate reductase (MTHFR) gene and cerebral venous thrombosis (CVT) remains controversial. This study principally investigated the potential role of the MTHFR A1298C variant and CVT. The genotyping of the A1298C variant of the MTHFR gene was performed in 35 CVT patients and 200 healthy controls. The frequency of A1298C genotype among CVT patients was significantly higher compared with controls (P?A1298C variant and CVT. Large study populations would be required to understand the contribution of this marker in the risk of CVT. PMID:23314385

Fekih-Mrissa, Najiba; Klai, Sarra; Mrad, Meriem; Zaouali, Jamel; Sayeh, Aycha; Nsiri, Brahim; Gritli, Nasreddine; Mrissa, Ridha

2013-03-01

8

Two cousins with neonatal stroke, PAI-1 4G variant and MTHFR A1298C mutation.  

PubMed

The authors describe 2 female cousins with neonatal stroke. One was heterozygous for the plasminogen activator inhibitor-1 4G variant and compound heterozygous for the A1298C and C677T methylenetetrahydrofolate reductase mutations. Her cousin was homozygous for the plasminogen activator inhibitor-1 4G variant and heterozygous for the methylenetetrahydrofolate reductase A1298C and factor V Leiden mutations. PMID:17641264

Golomb, Meredith R; Heiny, Mark; Garg, Bhuwan P

2007-06-01

9

Homocysteine Level and Mechanisms of Injury in Parkinson's Disease as Related to MTHFR, MTR, and MTHFD1 Genes Polymorphisms and L-Dopa Treatment  

PubMed Central

An elevated concentration of total homocysteine (tHcy) in plasma and cerebrospinal fluid is considered to be a risk factor for Alzheimer's disease (AD) and Parkinson's disease (PD). Homocysteine (Hcy) levels are influenced by folate concentrations and numerous genetic factors through the folate cycle, however, their role in the pathogenesis of PD remains controversial. Hcy exerts a neurotoxic action and may participate in the mechanisms of neurodegeneration, such as excitotoxicity, oxidative stress, calcium accumulation, and apoptosis. Elevated Hcy levels can lead to prooxidative activity, most probably through direct interaction with N-methyl-D-aspartate (NMDA) receptors and sensitization of dopaminergic neurons to age-related dysfunction and death. Several studies have shown that higher concentration of Hcy in PD is related to long-term administration of levodopa (L-dopa). An elevation of plasma tHcy levels can also reflect deficiencies of cofactors in remethylation of Hcy to methionine (Met) (folates and vitamin B12) and in its transsulfuration to cysteine (Cys) (vitamin B6). It is believed that the increase in the concentration of Hcy in PD can affect genetic polymorphisms of the folate metabolic pathway genes, such as MTHFR (C677T, A1298C and G1793A), MTR (A2756G), and MTHFD1 (G1958A), whose frequencies tend to increase in PD patients, as well as the reduced concentration of B vitamins. In PD, increased levels of Hcy may lead to dementia, depression and progression of the disease.

Rozycka, Agata; Jagodzinski, Pawel P.; Kozubski, Wojciech; Lianeri, Margarita; Dorszewska, Jolanta

2013-01-01

10

Comparing techniques for the identification of the MTHFR A1298C polymorphism.  

PubMed

The restriction fragment length polymorphism (RFLP) technique with the MboII enzyme is used by a number of researchers as a methodology for the identification of the genetic polymorphism MTHFR A1298C. However, the reliability of this enzyme for genotyping this polymorphism has been questioned, since the silent polymorphism T1317C, located close to the polymorphic region A1298C on gene MTHFR, also has a recognition site for MboII. Thus, the fragments formed by the digestion of MboII present similar sizes, making it difficult to differentiate the allele MTHFR 1298A in the presence of the allele MTHFR 1317C. Hence, we investigated the A1298C polymorphism in a Brazilian population of renal transplant patients, using the RFLP technique with digestion by Mbo II and using sequencing, in order to examine the concordance between the two techniques. Our results showed an 8.6% difference in genotyping between RFLP and sequencing, but the statistical concordance test presented a kappa coefficient equal to 0.81 (CI 95% 0.74-88), which indicates a virtually perfect concordance, according to the criterion of Landis and Koch. Therefore, we concluded that the RFLP technique is concordant with automated sequencing in the detection of polymorphism A1298C under our laboratory conditions. PMID:19137091

de Alvarenga, Maria Paula Sanches; Pavarino-Bertelli, Erika Cristina; Goloni-Bertollo, Eny Maria

2008-04-01

11

Association between dietary intake of folate, vitamin B6, B12 & MTHFR, MTR Genotype and breast cancer risk  

PubMed Central

Objective: we conducted a case-control study to investigate the association between dietary folate, vitamin B6 and vitamin B12 intake, MTHFR and MTR genotype, and breast cancer risk. Methods: Genotyping for MTHFR C677T and A1298C and MTR A2756G polymorphisms were performed using polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) method. The intake of folate, vitamin B6 and vitamin B12 were calculated by each food item from questionnaire. Results: Subjects with breast cancer tended to have more first-degree relatives (?2=30.77, P<0.001) and have high intake of folate (t=2.42, P=0.008) and Vitamin B6 (t=2.94, P=0.002). Compared to the reference group, women with MTHFR 677 TT genotype and T allele had a significantly increased risk of breast cancer, with ORs (95%CI) of 1.8(1.08-2.27) and 1.39(1.02-1.92), respectively. For those who had folate intake?450 ug/day, MTHFR 667TT genotype was associated with a higher risk of breast cancer (OR=2.45, 95% CI=1.09-5.82, P=0.02). Similarly, subjects with Vitamin B6 intake?0.84 mg/day and MTHFR 667T allele genotype was correlated with a marginally increased risk of breast cancer. A significant interaction was observed between MTHFR C667T polymorphism and folate intake on the risk of breast cancer (P for interaction was 0.025). Conclusion: This case-control study found a significant association between MTHFR C667T polymorphism, folate intake and vitamin B6 and breast cancer risk, and a significant interaction was observed between MTHFR C667T polymorphism and folate intake on the risk of breast cancer.

Weiwei, Zheng; Liping, Chen; Dequan, Li

2014-01-01

12

Association between dietary intake of folate, vitamin B6, B12 & MTHFR, MTR Genotype and breast cancer risk.  

PubMed

Objective: we conducted a case-control study to investigate the association between dietary folate, vitamin B6 and vitamin B12 intake, MTHFR and MTR genotype, and breast cancer risk. Methods: Genotyping for MTHFR C677T and A1298C and MTR A2756G polymorphisms were performed using polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) method. The intake of folate, vitamin B6 and vitamin B12 were calculated by each food item from questionnaire. Results: Subjects with breast cancer tended to have more first-degree relatives (?(2) =30.77, P<0.001) and have high intake of folate (t=2.42, P=0.008) and Vitamin B6 (t=2.94, P=0.002). Compared to the reference group, women with MTHFR 677 TT genotype and T allele had a significantly increased risk of breast cancer, with ORs (95%CI) of 1.8(1.08-2.27) and 1.39(1.02-1.92), respectively. For those who had folate intake?450 ug/day, MTHFR 667TT genotype was associated with a higher risk of breast cancer (OR=2.45, 95% CI=1.09-5.82, P=0.02). Similarly, subjects with Vitamin B6 intake?0.84 mg/day and MTHFR 667T allele genotype was correlated with a marginally increased risk of breast cancer. A significant interaction was observed between MTHFR C667T polymorphism and folate intake on the risk of breast cancer (P for interaction was 0.025). Conclusion: This case-control study found a significant association between MTHFR C667T polymorphism, folate intake and vitamin B6 and breast cancer risk, and a significant interaction was observed between MTHFR C667T polymorphism and folate intake on the risk of breast cancer. PMID:24639841

Weiwei, Zheng; Liping, Chen; Dequan, Li

2014-01-01

13

Prevalence of MTHFR C677T and MS A2756G polymorphisms in major depressive disorder, and their impact on response to fluoxetine treatment  

PubMed Central

Objective To examine the prevalence of the C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene and the A2756G polymorphism of methionine synthase (MS), and their impact on antidepressant response. Methods We screened 224 subjects (52% female, mean age 39 ± 11 years) with SCID-diagnosed major depressive disorder (MDD), and obtained 194 genetic samples. 49 subjects (49% female, mean age 36 ± 11 years) participated in a 12-week open clinical trial of fluoxetine 20–60 mg/day. Association between clinical response and C677T and A2756G polymorphisms, folate, B12, and homocysteine was examined. Results Prevalence of the C677T and A2756G polymorphisms was consistent with previous reports (C/C=41%, C/T=47%, T/T=11%, A/A=66%, A/G=29%, G/G=4%). In the fluoxetine-treated subsample (n=49), intent-to-treat (ITT) response rates were 47% for C/C subjects and 46% for pooled C/T and T/T subjects (nonsignificant). ITT response rates were 38% for A/A subjects and 60% for A/G subjects (nonsignificant), with no subjects exhibiting the G/G homozygote. Mean baseline plasma B12 was significantly lower in A/G subjects compared to A/A, but folate and homocysteine levels were not affected by genetic status. Plasma folate was negatively associated with treatment response. Conclusion The C677T and A2756G polymorphisms did not significantly affect antidepressant response. These preliminary findings require replication in larger samples.

Mischoulon, David; Lamon-Fava, Stefania; Selhub, Jacob; Katz, Judith; Papakostas, George I.; Iosifescu, Dan V.; Yeung, Albert S.; Dording, Christina M.; Farabaugh, Amy H.; Clain, Alisabet J.; Baer, Lee; Alpert, Jonathan E.; Nierenberg, Andrew A.; Fava, Maurizio

2014-01-01

14

Methylenetetrahydrofolate reductase gene A1298C polymorphism and susceptibility to recurrent pregnancy loss: a meta-analysis.  

PubMed

Environmental and genetic factors are thought to be involved in the pathogenesis of recurrent pregnancy loss (RPL)/spontaneous abortions (SA), which include endocrine, anatomical abnormalities within the genital organs, autoimmune diseases and some gene variants. Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of the folate/methionine metabolic pathway and it is well established fact that folate deficiency causes pregnancy complications like recurrent pregnancy loss, preeclempsia and birth defects affected pregnancies. MTHFR A1298C polymorphism reduces the enzymatic activity and mimics as folate deficiency. To date, many studies have investigated the association between MTHFR A1298C polymorphism and RPL risk; however, the result is still controversial and inconclusive. The aim of the present study was to address the association of MTHFR A1298C polymorphism with RPL risk by meta—analysis. By searching electronic databases, total seventeen studies were identified for present meta—analysis. Crude odds ratios (OR) with 95 % confidence intervals (CIs) was used to assess the strength of association between A1298C polymorphism and RPL. The results indicate that the A1298C polymorphism is not associated with RPL (ORCvs A = 1.13 ,95 % CI= 0.87—1.46, P = 0.36 ; ORACvs AA = 1.22 ,95 % CI= 0.94— 1.6, P = 0.13; ORCCvsAA =1.35, 95 % CI= 76—2.36, P = 0.30; ORCC+AC vs AA = 1.15, 95 % CI= 88 —1.49, P = 0.29; ORCCvs AC+AA = 1.29, 95 % CI= 76 —2.12, P = 0.34). Further prospective studies were needed to confirm the precise relationship between the MTHFR A1298C polymorphism and RPL. PMID:24970119

Rai, V

2014-01-01

15

Methionine synthase A2756G polymorphism may predict ulcerative colitis and methylenetetrahydrofolate reductase C677T pancolitis, in Central China  

PubMed Central

Background The association of genetic polymorphisms related to metabolism of homocysteine with inflammatory bowel disease has been evidenced in Crohn disease and remains an open question in ulcerative colitis. We evaluated the association of the polymorphisms of MTHFR, MTR, MTRR and TCN2 genes with ulcerative colitis in Central China. Methods 168 patients were genotyped for these polymorphisms and compared to 219 matched controls. Results Methionine synthase 2756G allele frequency was higher in ulcerative colitis than in controls 0.15 (95% C.I. 0.11–0.19) vs 0.09 (95% C.I. 0.07 – 0.12), (P = 0.0137) and predicted ulcerative colitis risk in logistic regression, with an Odds ratio at 1.8 (95% C.I. 1.15–2.84). Methylenetetrahydrofolate reductase 677TT genotype was 2.7-fold more prevalent in individuals with pancolitis than in those with left colitis or proctitis, with respective percentages of 27.3 (95% C.I.16.4–42.0) and 10.5 (95% C.I. 6.3–17.1) (P = 0.0123). The carriage of 677TT or 677CT/1298AC genotypes of methylenetetrahydrofolate reductase was more frequent in cases with pancolitis than in subjects with left colitis or proctitis (P = 0.0048), with an Odds ratio adjusted by age and sex at 3.3 (95% C.I. 1.4–7.9), P = 0.0084) in logistic regression. Conclusion Methionine synthase and methylenetetrahydrofolate reductase are genes of vitamin B12 and folate cellular metabolism associated respectively with risk and extent of ulcerative colitis, at least in Central China. This finding may open new insights, particularly for the potential interest in treating patients carrying the 677TT MTHFR genetic trait and a deficit in folate.

Chen, Min; Peyrin-Biroulet, Laurent; Xia, Bing; Gueant-Rodriguez, Rosa-Maria; Bronowicki, Jean-Pierre; Bigard, Marc-Andre; Gueant, Jean-Louis

2008-01-01

16

Association of methylenetetrahydrofolate reductase (A1298C and C677T) polymorphisms with retinal vein occlusion in Tunisian patients.  

PubMed

The role of two polymorphisms C677T and A1298C of the methylenetetrahydrofolate reductase (MTHFR) gene in the etiology of retinal vein occlusion (RVO) has not been adequately clarified. The aim of this study was to examine the prevalence of these polymorphisms among RVO Tunisian patients with and without systemic risk factors. Seventy-two patients with retinal vein occlusion (RVO) were studied. The control group included140 people matched for age, sex, and risk factors. Participants in the study were genotyped for the MTHFR C677T and A1298C polymorphisms. The genotyping was performed by PCR-RFLP. No significant differences were found in the frequencies of the three genotypes (AA, AC, CC) of the MTHFR A1298C polymorphism between RVO patients and healthy controls. However, the prevalence of the group of mutated genotypes (AC+CC) of the missense variant MTHFR A1298C was significantly different between patients and controls (16.67% vs. 6.42%, p=.01). Additionally, the frequency of the CT genotype as well as the group of combined mutated genotypes (CT+TT) for the C677T variant was significantly higher among RVO patients compared with controls (p<10(-3), p<10(-3)). This suggests an association between this polymorphism and RVO. Large study populations would be required to understand more completely the contribution of these markers in the risk of RVO. PMID:24440586

Mrad, Meriem; Wathek, Cheima; Saleh, Mekki Ben; Baatour, Makrem; Rannen, Riadh; Lamine, Khaled; Gabsi, Salem; Gritli, Nasreddine; Fekih-Mrissa, Najiba

2014-04-01

17

Increased frequency of combined methylenetetrahydrofolate reductase C677T and A1298C mutated alleles in spontaneously aborted embryos  

Microsoft Academic Search

The pathogenesis of spontaneous abortion is complex, presumably involving the interaction of several genetic and environmental factors. The methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms are commonly associated with defects in folate dependent homocysteine metabolism and have been implicated as risk factors for recurrent embryo loss in early pregnancy. In the present study we have determined the prevalence of

Henrik Zetterberg; Björn Regland; Mona Palmér; Anne Ricksten; Lars Palmqvist; Lars Rymo; Demetrios A Arvanitis; Demetrios A Spandidos; Kaj Blennow

2002-01-01

18

C677T and A1298C Polymorphisms of MTHFR Gene and Their Relation to Homocysteine Levels in Turner Syndrome  

PubMed Central

Aims: To determine the frequency of C677T and A1298C polymorphisms of the MTHFR gene and correlate them with homocysteine serum levels in patients with Turner syndrome (TS) and controls. Methods: This case–control study included 78 women with TS and a control group of 372 healthy individuals without personal or family history of cardiovascular disease and cancer. C677T (rs1801133) and A1298C (rs1801131) polymorphisms were detected by polymerase chain reaction–restriction fragment-length polymorphism and the TaqMan system, respectively. Homocysteine serum levels were determined by high-performance liquid chromatography. The results were analyzed statistically, and p<0.05 was considered to represent a significant difference. Results: The homocysteine levels change was 13.9+3.3 nM in patients with TS and 8.8+3.2?nM in the control group. No significant difference between groups was found (p=0.348). Single-marker analysis revealed no association between MTHFR C677T polymorphism and TS when genotype (p=0.063) or allelic (p=0.277) distribution was considered. Regarding MTHFR A1298C polymorphism, a statistical difference was found between the TS group and the control group, for both genotype (p<0.0001) and allele (p<0.0001) distribution. Haplotype analysis of 2 MTHFR polymorphisms identified 2 haplotypes—CC and TC—associated with TS (p<0.001 and p=0.0165, respectively). However, homocysteine levels were not higher in patients with haplotype risk. Conclusion: The results suggest that the C677T and A1298C polymorphisms of the MTHFR gene are not related to homocysteine levels in Brazilian patients with TS, despite the differential distribution of the mutated allele C (A1298C) in these patients. Further studies are needed to investigate the possible genetic interaction with homocysteine levels in TS.

Oliveira, Kelly C.; Verreschi, Ieda T.N.; Sugawara, Eduardo K.; Silva, Vanessa C.; Galera, Bianca B.; Galera, Marcial Francis; Bianco, Bianca

2012-01-01

19

Association of MTHFR A1298C polymorphism (but not of MTHFR C677T) with elevated homocysteine levels and placental vasculopathies.  

PubMed

Our aim in this study was to investigate the association between elevated homocysteine levels and the two MTHFR polymorphisms, C677T and A1298C, with several pregnancy complications such as recurrent pregnancy loss, preeclampsia, placental abruption and intrauterine growth retardation. In 203 women with different placental vasculopathies, we determined the MTHFR C677T and the A1298C prevalence and their relative association to elevated homocysteine levels. The mean plasma homocysteine level was significantly higher in the pathologic groups when compared with the control group. We identified the carriage of the MTHFR A1298C polymorphism as a significant risk factor for vascular-related pregnancy complications. Women with MTHFR A1298C polymorphism or elevated homocysteine levels have an increased risk of placental vasculopathies. The MTHFR A1298C mutation also had a positive impact on elevated homocysteine levels. The lack of association between the MTHFR C677T polymorphism and pregnancy morbidities needs further studies. PMID:21577095

Klai, Sarra; Fekih-Mrissa, Najiba; El Housaini, Sonia; Kaabechi, Naziha; Nsiri, Brahim; Rachdi, Radhouen; Gritli, Nasredine

2011-07-01

20

Association of the methylenetetrahydrofolate reductase gene A1298C polymorphism with stroke risk based on a meta-analysis.  

PubMed

Several independent studies have reported the role of the methylenetetrahydrofolate reductase gene (MTHFR) A1298C polymorphism in strokes, but the results are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed in the present study. In this meta-analysis, a total of 13 studies, including 1974 cases and 2660 controls, were selected to evaluate the possible association. Crude odds ratios (ORs) with 95% confidence intervals (CI) were used to assess the strength of the association in additive, dominant, and recessive models. The overall analysis showed that MTHFR A1298C was associated with a significant increase in the risk of stroke in the heterozygote comparison (AC vs AA: OR = 1.17; 95%CI = 1.03-1.34) and in the dominant model (AC/CC vs AA: OR = 1.22; 95%CI = 1.01-1.49). Stratified analysis showed a significantly strong association between the MTHFR A1298C polymorphism and stroke risk in Asian populations (OR = 1.32 for AC vs AA; OR = 1.94 for CC vs AA; OR = 1.37 for AC/CC vs AA; OR = 1.33 for C vs A allele), but not in Caucasian populations. Additionally, the MTHFR 1298C allele was found to be a risk factor for developing ischemic strokes. However, no statistically significant increased risk of hemorrhagic stroke was found in any of the genetic models. In conclusion, this meta-analysis supported that the MTHFR A1298C polymorphism could be capable of increasing stroke susceptibility in Asian, but not in Caucasian, populations. PMID:24391036

Lv, Q; Lu, J; Wu, W; Sun, H; Zhang, J

2013-01-01

21

Methylenetetrahydrofolate reductase C677T and A1298C variants do not affect ongoing pregnancy rates following IVF  

Microsoft Academic Search

BACKGROUND: There is concern that IVF could compromise normal imprinting and methylation of DNA. Methyl- enetetrahydrofolate reductase (MTHFR) regulates the flow of folic acid-derived, one-carbon moieties for methylation and is critical to early embryonic development. Therefore, we hypothesized that common polymorphisms in MTHFR could associate with IVF outcome. METHODS: MTHFR C677T and A1298C polymorphism genotyping was per- formed on 374

A. T. Dobson; R. M. Davis; M. P. Rosen; S. Shen; P. F. Rinaudo; J. Chan; M. I. Cedars

2006-01-01

22

MTHFR polymorphisms C677T and A1298C and associations with IVF outcomes in Brazilian women.  

PubMed

The aim of this study was to investigate the association between MTHFR gene polymorphisms and IVF outcomes in Brazilian women undergoing assisted reproduction treatment. A prospective study was conducted in the Human Reproduction Department at the ABC University School of Medicine and the Ideia Fertility Institute between December 2010 and April 2012. The patient population was 82 women undergoing assisted reproduction cycles. The MTHFR polymorphisms C677T and A1298C were evaluated and compared with laboratory results and pregnancy rates. The C677T variant was associated with proportions of mature (P=0.006) and immature (P=0.003) oocytes whereas the A1298C variant was associated with number of oocytes retrieved (P=0.044). The polymorphisms, whether alone or in combination, were not associated with normal fertilization, good-quality embryo or clinical pregnancy rates. This study suggests that the number and maturity of oocytes retrieved may be related to the MTHFR polymorphisms C677T and A1298C. It is believed that folate has a crucial function in human reproduction and that folate deficiency can compromise the function of the metabolic pathways it is involved in, leading to an accumulation of homocysteine. The gene MTHFR encodes the 5-MTHFR enzyme, which is involved in folate metabolism, and C677T/A1298C polymorphisms of this gene are related to decreased enzyme activity and consequent changes in homocysteine concentration. Folate deficiency and hyperhomocysteinaemia can also compromise fertility and lead to pregnancy complications by affecting the development of oocytes, preparation of endometrial receptivity, implantation of the embryo and pregnancy. In folliculogenesis, hyperhomocysteinaemia can activate apoptosis, leading to follicular atresia and affecting the maturity of oocytes and the quality of embryos cultured in vitro. This study was performed to investigate the association between MTHFR polymorphisms and IVF outcomes in women undergoing assisted reproduction treatment. PMID:24746944

D'Elia, Priscila Queiroz; Dos Santos, Aline Amaro; Bianco, Bianca; Barbosa, Caio Parente; Christofolini, Denise Maria; Aoki, Tsutomu

2014-06-01

23

Methylenetetrahydrofolate reductase gene C677T, A1298C polymorphisms and pre-eclampsia risk: a meta-analysis.  

PubMed

To determine whether methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms are associated with pre-eclampsia susceptibility. Literature searches of the Pubmed, Embase, BIOSIS Previews and Web of Science were conducted to identify all eligible articles up to January 18th, 2013. The pooled odds ratios (ORs) with 95 % confidence intervals (CIs) of five genetic models were calculated by fixed-effects or random-effects model. Publication bias, subgroup analysis, meta-regression and sensitivity analysis were also performed. A number of 49 studies including 51 samples consisted of 18,009 subjects (6,238 patients and 11,771 controls) were finally included. MTHFR C677T allele (TT or CT) carriers were 1.12 times more likely to develop pre-eclampsia (95 % CI 1.04-1.21) compared with 677CC homozygous individuals. Similar results were obtained under other genetic models. Restricted to severe pre-eclampsia, there was an increased risk for 677TT homozygotes compared with 677CC homozygotes (OR 1.43; 95 % CI 1.12-1.83). Subgroup analysis revealed a significant positive association between the C677T polymorphism (TT or CT) and pre-eclampsia in Asians (OR 1.41; 95 % CI 1.11-1.79) and white population (OR 1.14; 95 % CI 1.03-1.25). Meta-regression showed that study population, blinded genotyping, matching of cases and controls were not substantial sources of heterogeneity. For the MTHFR A1298C, ORs for all genetic models yielded a null association. This meta-analysis suggests that the MTHFR 677T allele might be associated with increased pre-eclampsia risk in Asian and white ethnicity and the subgroup of severe pre-eclampsia, while no association is observed between the MTHFR A1298C polymorphism and pre-eclampsia. PMID:24898880

Li, Xing; Luo, Ya L; Zhang, Qiong H; Mao, Chen; Wang, Xi W; Liu, Shan; Chen, Qing

2014-08-01

24

Population distribution of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C risk alleles for methotrexate toxicity in Israel.  

PubMed

Methylenetetrahydrofolate reductase (MTHFR) is a central regulatory enzyme in the folate pathway. Two non-synonymous single nucleotide polymorphisms in MTHFR, C677T (rs1801133) and A1298C (rs1801131) have been associated with reduced MTHFR enzyme activity. These polymorphisms, especially C677T, appear to be linked with methotrexate-related toxicity, particularly hepatotoxicity; thus, pretreatment identification of individuals carrying these polymorphisms may be of clinical relevance. The purpose of this study was to determine the frequency and distribution of MTHFR polymorphic variants, known to functionally impair MTHFR activity, in the highly heterogeneous Israeli population. MTHFR genotyping was carried out in the representatives of three major demographic groups in Israel by PCR-restriction fragment length polymorphism and high-resolution melting. The relative distribution of variant alleles 677T and 1298C was found to be similar in individuals of Jewish, Druze and Arab Moslem descent (p = 0.09). However, Ashkenazi Jews displayed a 1.9-fold higher frequency of variant 677T and a 1.8-fold lower frequency of variant 1298C compared to non-Ashkenazi Jews (p < 0.001). Distinct differences in the relative frequencies of both polymorphisms were also found between Ashkenazi Jews and Druze (p < 0.01 for C677T, p < 0.01 for A1298C) or Ashkenazi Jews and Arab Moslem (p < 0.01 for C677T, p < 0.05 for A1298C). These data underscore the importance of geographic genetic analysis for a better understanding of human pharmacotherapy and personalized medicine. PMID:22847291

Efrati, Edna; Elkin, Hela; Nahum, Sagi; Krivoy, Norberto

2013-04-01

25

MTHFR A1298C and C677T gene polymorphisms and susceptibility to chronic myeloid leukemia in Egypt  

PubMed Central

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme regulating the intracellular folate metabolism which plays an important role in carcinogenesis through DNA methylation. We aimed to evaluate the association between MTHFR A1298C and C677T polymorphisms and the risks of chronic myeloid leukemia (CML). Eighty-five patients with CML and a control group containing 100 healthy, age and sex matched individuals were examined for MTHFR C677T and A1298C polymorphisms using polymerase chain reaction-restriction fragment-length (PCR-RFLP) method. The frequency of 677TT genotype in patients with CML was significantly higher compared to controls (OR = 2.513, 95% CI: 0.722-4.086, P = 0.025). No such association was shown for heterozygous 677CT (OR = 1.010, 95% CI: 0.460-2.218, P = 0.981). Moreover, for A1298C genotype, a statistically significant higher frequency of 1298CC was also detected in CML patients compared to control group (OR = 1.1816, 95% CI: 0.952-3.573, P = 0.036), 0.036). No such statistical significance was demonstrable for heterozygote 1298AC (OR = 1.046, 95% CI: 0.740-1.759, P = 0.092). In addition, patients with joint 677CT/1298AC or 677TT/1298CC genotypes showed an association with increased risk of CML (OR = 1.849, 95% CI: 0.935-2.540, P = 0.024; OR = 1.915, 95% CI: 1.202-3.845, P = 0.020 respectively). .A statistically significant increased risk of resistant to therapy was observed with 677CT and 1298AC genotypes (P = 0.001, P = 0.002 respectively). We conclude that both MTHFR 677TT and 1298CC polymorphisms have been associated with risk of CML and both 677CT and 1298AC genotypes are associated with higher risk of resistant to therapy.

Aly, Rabab M; Taalab, Mona M; Ghazy, Hayam F

2014-01-01

26

Association of MTRRA66G polymorphism (but not of MTHFR C677T and A1298C, MTRA2756G, TCN C776G) with homocysteine and coronary artery disease in the French population.  

PubMed

Methylenetetrahydrofolate reductase polymorphism (MTHFR C677T) is an established determinant of homocysteine plasma level (t-Hcys) while its association with coronary artery disease (CAD) seems to be more limited. In contrast, the association of the substitutions A2756G of methionine synthase (MTR), A66G of methionine synthase reductase (MTRR) and C776G of transcobalamin (TCN) to both t-Hcys and CAD needs to be evaluated further. The objective was to evaluate the association of these polymorphisms with t-Hcys and CAD in a French population. We investigated the individual and combined effects of these polymorphisms and of vitamin B12 and folates with t-Hcys in 530 CAD patients and 248 matched healthy controls. t-Hcys was higher in the CAD group than in controls (11.8 vs 10.4 microM, P < 0.0001) and in carriers of MTRRAA and MTHFR 677TT than in those carrying the most frequent allele of both polymorphisms (13.8 vs 11.4 microM, P = 0.0102 and 12.5 vs 11.0 mM, P = 0.0065 respectively). The frequency of MTRR A allele was higher in CAD patients than in controls (0.48 [95% CI: 0.44-0.52] vs 0.38 [95% CI: 0.32-0.44], P = 0.0081) while no difference was observed for MTHFR 677T frequency. In multivariate analysis, t-Hcys > median and MTRRAA genotype were two significant independent predictors of CAD with respective odds ratios of 3.1 (95 % CI: 1.8-5.1, P < 0.0001) and 4.5 (95% CI: 1.5-13.1, P = 0.0051). In conclusion, in contrast to North Europe studies, MTRRAA genotype is a genetic determinant of moderate hyperhomocysteinemia associated with CAD in a French population without vitamin fortification. PMID:16268464

Guéant-Rodriguez, Rosa-Maria; Juilliére, Yves; Candito, Mirande; Adjalla, Charles E; Gibelin, Pierre; Herbeth, Bernard; Van Obberghen, Emmanuel; Gueánt, Jean-Louis

2005-09-01

27

Association of the C677T and A1298C polymorphisms in the 5,10 methylenetetrahydrofolate reductase gene in patients with migraine risk  

Microsoft Academic Search

Although controversial, diminished activity of 5,10 methylenetetrahydrofolate reductase (MTHFR), a regulatory enzyme of homocysteine metabolism, may predispose to migraine in Turkish people. In a case-control study, we determined the prevalence of two common MTHFR polymorphisms,C677T and A1298C, in 102 migraine patients (23 migraine with aura, 70 migraine without aura and nine with tension-type headache) and compared it to that of

Ihsan Kara; Ali Sazci; Emel Ergul; Guner Kaya; Gamze Kilic

2003-01-01

28

C677T and A1298C polymorphisms of the methylenetetrahydrofolate reductase gene: effect on methotrexate-related toxicity in adult acute lymphoblastic leukaemia.  

PubMed

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme involved in folate metabolism. Two polymorphisms, C677T and A1298C, were described leading to reduced enzyme activity. Methotrexate (MTX) is an antifolate agent of consolidation and maintenance therapy of acute lymphoblastic leukaemia (ALL). Despite its clinical success, MTX can be associated with serious toxicities resulting in treatment interruption or discontinuation, impacting disease outcome. There is evidence that MTX toxicity can be affected by polymorphisms in genes encoding for drug-metabolizing enzymes such as MTHFR. Therefore, we aimed to investigate the influence of MTHFR C677T and A1298C polymorphisms on the frequency of MTX-related toxicity, disease outcome and patients' survival. MTHFR polymorphisms were assessed in 50 adult patients with de novo ALL using real-time PCR. Patients were followed-up for the development of haematologic and/or nonhaematologic toxicity and assessment of clinical outcome. Frequency of C677T polymorphisms was 42% for TT, 24% for CT and 34% for CC; A1298C polymorphisms were 28, 6 and 66% for CC, AC and AA, respectively. MTX therapy was significantly associated with neutropaenia, hepatic and gastrointestinal toxicities, unfavourable response at day 14 of induction therapy, increased relapse and mortality rates and shorter survival in patients with 677 TT genotype than in those with CC and CT, whereas 1298 CC genotype patients had lower frequency of neutropaenia, hepatic toxicity and relapse than in those with AA and AC. Our study suggests MTHFR polymorphism as an attractive predictor of MTX-related toxicity in adult ALL, considering it a potential prognostic factor influencing disease outcome. PMID:23183238

Eissa, Deena Samir; Ahmed, Tamer Mohamed

2013-03-01

29

Association of methylenetetrahytrofolate reductase (MTHFR) C677T and A1298C polymorphisms with the susceptibility of childhood acute lymphoblastic leukaemia (ALL) in Chinese population  

PubMed Central

Background The aim of this study was to investigate the relationship between the polymorphisms of the methylenetetrahytrofolate reductase (MTHFR) gene and susceptibility to childhood acute lymphoblastic leukemia (ALL). Methods A case–control study was conducted among 98 children with ALL and 93 age- and sex- matched non-ALL controls. Genotyping of MTHFR C677T and A1298C polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The odds ratios (ORs) of MTHFR genotypes were used to assess the associations of these polymorphisms with childhood ALL susceptibility. Results No significant differences were observed for frequencies of the 677CC, 677CT and 677TT genotypes between patients and controls. Frequencies of the 1298AA, 1298 AC and 1298CC genotypes between the two groups were significantly different. The risk of ALL with the 1298C allele carriers (AC?+?CC) was elevated by 1.1 times compared with the AA genotype [OR?=?2.100; 95% CI (1.149; 3.837); P?=?0.015]. Conclusions The MTHFR A1298C polymorphism is associated with susceptibility to childhood ALL in the Chinese population.

2014-01-01

30

Effects of Maternal 5,10-Methylenetetrahydrofolate Reductase C677T and A1298C Polymorphisms and Tobacco Smoking on Infant Birth Weight in a Japanese Population  

PubMed Central

Background Intracellular folate hemostasis depends on the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene. Because 5,10-MTHFR 677TT homozygosity and tobacco smoking are associated with low folate status, we tested the hypothesis that smoking in mothers with 5,10-MTHFR C677T or A1298C polymorphisms would be independently associated with lower birth weight among their offspring. Methods We assessed 1784 native Japanese mother-child pairs drawn from the ongoing birth cohort of The Hokkaido Study on Environment and Children’s Health. Data (demographic information, hospital birth records, and biological specimens) were extracted from recruitments that took place during the period from February 2003 to March 2006. Maternal serum folate were assayed by chemiluminescent immunoassay, and genotyping of 5,10-MTHFR C677T/A1298C polymorphisms was done using a TaqMan allelic discrimination assay. Results The prevalence of folate deficiency (<6.8 nmol/L) was 0.3%. The 5,10-MTHFR 677CT genotype was independently associated with an increase of 36.40 g (95% CI: 2.60 to 70.30, P = 0.035) in mean infant birth weight and an increase of 90.70 g (95% CI: 6.00 to 175.50, P = 0.036) among male infants of nonsmokers. Female infants of 677TT homozygous passive smokers were 99.00 g (95% CI: ?190.26 to ?7.56, P = 0.034) lighter. The birth weight of the offspring of smokers with 5,10-MTHFR 1298AA homozygosity was lower by 107.00 g (95% CI: ?180.00 to ?33.90, P = 0.004). Conclusions The results suggest that, in this population, maternal 5,10-MTHFR C677T polymorphism, but not the 5,10-MTHFR A1298C variant, is independently associated with improvement in infant birth weight, especially among nonsmokers. However, 5,10-MTHFR 1298AA might be associated with folate impairment and could interact with tobacco smoke to further decrease birth weight.

Yila, Thamar Ayo; Sasaki, Seiko; Miyashita, Chihiro; Braimoh, Titilola Serifat; Kashino, Ikuko; Kobayashi, Sumitaka; Okada, Emiko; Baba, Toshiaki; Yoshioka, Eiji; Minakami, Hisanori; Endo, Toshiaki; Sengoku, Kazuo; Kishi, Reiko

2012-01-01

31

Geographical Distribution of MTHFR C677T, A1298C and MTRR A66G Gene Polymorphisms in China: Findings from 15357 Adults of Han Nationality  

PubMed Central

Background Methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms are important genetic determinants for homocysteine (Hcy) levels, and are associated with several disorders. These polymorphisms are heterogeneously distributed worldwide. Our objective was to explore the geographical distributions of these polymorphisms in China. Methodologies 15357 healthy adults were recruited from 10 regions. Buccal samples were collected and genomic DNA was isolated. Genotyping was performed using the fluorogenic 5?-nuclease assay. Principal Findings The prevalence of the three polymorphisms among different populations from China varied significantly and showed apparent geographical gradients. For MTHFR C677T, the frequencies of the 677T allele and the 677TT genotype were significantly higher among northern populations and ranged from the lowest values (24.0% and 6.4%, respectively) in Hainan (southern) to the highest values (63.1% and 40.8%, respectively) in Shandong (northern). For MTHFR A1298C, the 1298C allele and the 1298CC genotype frequencies were significantly higher among southern populations and increased from low values (13.1% and 1.4%, respectively) in Shandong to high values (25.7% and 6.7%, respectively) in Hainan. For A66G, the 66G allele and the 66GG genotype frequencies increased from lower values (23.7% and 5.4%, respectively) in Shandong to higher values (29.2% and 8.6%, respectively) in Hainan. The overall frequency of the 677T allele, 677TT genotype, 1298C allele, 1298CC genotype, 66G allele and 66GG genotype in the Chinese Han population was 45.2%, 23.2%, 18.6%, 3.9%, 25.7%, and 6.6%, respectively. No gender differences were found in the prevalence of both the MTHFR C677T and MTRR A66G polymorphisms. Conclusions This study indicates that there are marked geographical variations in the prevalence of the three polymorphisms among Chinese Han populations. Our baseline data may be useful for future researches in related fields.

Yang, Boyi; Liu, Yuyan; Li, Yongfang; Fan, Shujun; Zhi, Xueyuan; Lu, Xiangxiang; Wang, Da; Zheng, Quanmei; Wang, Yinuo; Wang, Yanxun; Sun, Guifan

2013-01-01

32

MTHFR C677T and A1298C Genotypes and Haplotypes in Slovenian Couples with Unexplained Infertility Problems and in Embryonic Tissues from Spontaneous Abortions.  

PubMed

The objective of this study was to analyze the methylenetetrahydrofolate reductases ( MTHFR s) C677T and A1298C genotype distributions in couples with unexplained fertility problems (UFP) and healthy controls, and to analyze the genotype and haplotype distribution in spontaneously aborted embryonic tissues (SAET) using allele specific polymerase chain reaction (PCR) in 200 probands with UFP, 353 samples of SAET and 222 healthy controls. The analysis revealed a significant overall representation of the 677T allele in male probands from couples with UFP ( p = 0.036). The combined genotype distribution for both MTHFR polymorphisms was also significantly altered (? (2) 21.73, p <0.001) although female probands made no contribution (? (2) 1.33, p = 0.72). The overall representation of the 677T allele was more pronounced in SAET (0.5 vs. 0.351 in controls, p <0.001) regardless of the karyotype status (aneuploidy vs. normal karyotype). In addition, the frequencies of the CA and CC haplotypes were significantly lower than in the control group ( p = 0.021 and p = 0.001, respectively), whereas the frequency of the TC haplotype was significantly higher than in controls ( p <0.0001). The presented findings indicate that only male probands contribute to the association of MTHFR mutations with fertility problems in grown adults and demonstrate a high prevalence of mutated MTHFR genotypes in SAET. PMID:24265582

Stangler Herodež, S; Zagradišnik, B; Erjavec Škerget, A; Zagorac, A; Taka?, I; Vlaisavljevi?, V; Lokar, L; Kokalj Voka?, N

2013-06-01

33

Hyperhomocysteinemia and related genetic polymorphisms correlate with ulcerative colitis in Chinese Han population in Central China [corrected].  

PubMed

Increased levels of homocysteine are found systemically and in intestinal mucosa of patients with inflammatory bowel disease, and, specifically, in ulcerative colitis (UC). However, there are controversial reports regarding the factors contributing to increased levels of homocysteine in UC. Furthermore, little information is available regarding the relationship between hyperhomocysteinemia (HHcy), vitamin status, and genetic polymorphisms of homocysteine-related enzymes in these patients. This study examined four functional polymorphisms linked to homocysteine metabolism (MTHFR C677T and A1298C, MTR A2756G and MTRR A66G), and evaluated plasma levels of homocysteine, folate, and vitamin B(12) in 310 consecutive patients with UC and 936 age- and sex-matched healthy controls from southeast China. The variant allele and genotypic frequencies in MTHFR A1298C, MTR A2756G and MTRR A66G genes were significantly higher in patients with UC compared to healthy controls. Further, HHcy and low levels of folate and vitamin B(12) were more frequent in patients with UC. The MTR 2756G allele, extent of the disease, and gender were the independent determinants of HHcy in these patients. These findings suggest that genetic and nutritional factors have a synergetic effect on HHcy in patients with UC. In conclusion, our data highlight a prevention strategy for moderation of HHcy and supplementation with folate and vitamine B(12) in patients with UC from Southeast China. PMID:21947961

Jiang, Yi; Xia, Xuanping; Wang, Wenxing; Lin, Limiao; Xu, Changlong; Cai, Zhenzai; Zheng, Bo; Pei, Jihua; Shen, Sujian; Xia, Bing

2012-01-01

34

Polymorphism C776G in the transcobalamin II gene and homocysteine, folate and vitamin B12 concentrations. Association with MTHFR C677T and A1298C and MTRR A66G polymorphisms in healthy children.  

PubMed

One of the etiologies of hyperhomocysteinemia is decreased vitamin B(12). Genetic variation in the transcobalamin II gene, the transporter of vitamin B(12) to the cells, may produce altered homocysteine levels. We determined transcobalamin II C776G polymorphism, homocysteine, folate and vitamin B(12) levels and analyzed the interactive effect with the methylenetetrahydrofolate reductase C677T and A1298C and methionine synthase reductase A66G polymorphisms in 207 healthy Brazilian children. The prevalence of GG genotype of transcobalamin II C776G polymorphism in this Brazilian population, a highly miscigeneous population was 12.5% and the statistical analysis showed that this population is in Hardy-Weinberg equilibrium, it could be considered representative of the general population. We observed a significant increase in homocysteine in the 776GG vs. 776CC genotype, corroborating the influence of age as a determinant of homocysteine in relation to this polymorphism. When we analyzed vitamin B(12) and its relationship with the C776G polymorphism, we found no significant differences. Only 776CG/66AA or 776GG/66AG genotypes presented a significant increase in homocysteine when compared with other groups. In the multivariate analysis, transcobalamin II C776G (CC/CG vs. GG), methylenetetrahydrofolate reductase C677T (CC/CT vs. TT), folate, gender and age presented statistical significance in relation to the homocysteine. These can be considered independent risk factors for hyperhomocysteinemia in this children group. Our results, if confirmed in other populations, highlight the necessity for investigation of the transcobalamin II C776G polymorphism in the research for hyperhomocysteinemia risk factors. PMID:16820193

Aléssio, Ana C M; Höehr, Nelci F; Siqueira, Lúcia H; Bydlowski, Sérgio P; Annichino-Bizzacchi, Joyce M

2007-01-01

35

MTR OFFICE WINGS AT WEST SIDE OF MTR HIGH BAY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR OFFICE WINGS AT WEST SIDE OF MTR HIGH BAY REACTOR BUILDING. CONTEXTUAL VIEW. CAMERA FACING NORTHEAST. FROM LEFT TO RIGHT, TRA-652 (OFFICE WING), TRA-661 (SOUTH WING EXTENSION), SECOND/THIRD FLOOR (BALCONIES) OF MTR-603, MTR HIGH-BAY. AT RIGHT EDGE OF VIEW IS REACTOR SERVICES BUILDING (TRA-635). INL NEGATIVE NO. HD46-44-1. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

36

MTR MAIN FLOOR. MTR TRACTOR IS IN CENTER OF VIEW ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR MAIN FLOOR. MTR TRACTOR IS IN CENTER OF VIEW AMIDST AN ACCUMULATION OF CLUTTER ON THE FLOOR. TRACTOR HAD ATTACHMENTS IN FRONT TO FACILITATE MOVING OF COFFINS. INL NEGATIVE NO. 56-3027. Jack L. Anderson, Photographer, 9/17/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

37

Detection of Thrombophilic Mutations Related to Spontaneous Abortions by a Multiplex SNaPshot Method  

PubMed Central

Spontaneous abortion is a significant clinical problem of different etiologies. Certain thrombophilia gene mutations have been associated with an increased risk of spontaneous abortion. Also, mutations in folate-related genes can lead to abnormal chromosomal segregation during meiosis which is the most common cause of spontaneous abortion. We have developed a multiplex single-base extension reaction assay that allows simultaneous analysis of 10 different mutations in thrombophilia- and folate-related genes (Factor V Leiden G1691A, Factor V H1299R, Factor II G20210A, Factor XIII V34L, PAI-I -675 4G/5G, FGB -455G/A, MTHFR C677T, MTHFR A1298C, MTR A2756G, and MTRR A66G). Using this method we have studied 232 women who had a spontaneous abortion and 209 of their male partners. Prevalence of Factor II G20210A and Factor V H1299R mutations was significantly higher in the women than in their male partners (2.4% and 0.7%, respectively [p=0.0499] for the Factor II mutation and 9.3% and 5.7%, respectively [p=0.0485] for the Factor V mutation). The prevalence of MTHFR C677T, MTHFR A1298C, MTR A2756G, and MTRR A66G mutations did not differ between the studied groups. In conclusion, we have developed a rapid, simple, reliable, and inexpensive multiplex SNaPshot method for determination of 10 thrombophilic mutations that may result in spontaneous abortions.

Madjunkova, Svetlana; Volk, Marija; Peterlin, Borut

2012-01-01

38

Genetic Variants in the Folate Pathway and the Risk of Neural Tube Defects: A Meta-Analysis of the Published Literature  

PubMed Central

Background Neural Tube Defects (NTDs) are among the most prevalent and most severe congenital malformations worldwide. Polymorphisms in key genes involving the folate pathway have been reported to be associated with the risk of NTDs. However, the results from these published studies are conflicting. We surveyed the literature (1996–2011) and performed a comprehensive meta-analysis to provide empirical evidence on the association. Methods and Findings We investigated the effects of 5 genetic variants from 47 study populations, for a total of 85 case-control comparisons MTHFR C677T (42 studies; 4374 cases, 7232 controls), MTHFR A1298C (22 studies; 2602 cases, 4070 controls), MTR A2756G (9 studies; 843 cases, 1006 controls), MTRR A66G (8 studies; 703 cases, 1572 controls), and RFC-1 A80G (4 studies; 1107 cases, 1585 controls). We found a convincing evidence of dominant effects of MTHFR C677T (OR 1.23; 95%CI 1.07–1.42) and suggestive evidence of RFC-1 A80G (OR 1.55; 95%CI 1.24–1.92). However, we found no significant effects of MTHFR A1298C, MTR A2756G, MTRR A66G in risk of NTDs in dominant, recessive or in allelic models. Conclusions Our meta-analysis strongly suggested a significant association of the variant MTHFR C677T and a suggestive association of RFC-1 A80G with increased risk of NTDs. However, other variants involved in folate pathway do not demonstrate any evidence for a significant marginal association on susceptibility to NTDs.

Zhang, Ti; Lou, Jiao; Zhong, Rong; Wu, Jing; Zou, Li; Sun, Yu; Lu, Xuzai; Liu, Li; Miao, Xiaoping; Xiong, Guanglian

2013-01-01

39

Evaluation of Factor V G1691A, prothrombin G20210A, Factor XIII V34L, MTHFR A1298C, MTHFR C677T and PAI-1 4G/5G genotype frequencies of patients subjected to cardiovascular disease (CVD) panel in south-east region of Turkey.  

PubMed

Cardiovascular disease (CVD) risk factors, such as arterial hypertension, obesity, dyslipidemia or diabetes mellitus, as well as CVDs, including myocardial infarction, coronary artery disease or stroke, are the most prevalent diseases and account for the major causes of death worldwide. In the present study, 4,709 unrelated patients subjected to CVD panel in south-east part of Turkey between the years 2010 and 2013 were enrolled and DNA was isolated from the blood samples of these patients. Mutation analyses were conducted using the real-time polymerase chain reaction method to screen six common mutations (Factor V G1691A, PT G20210A, Factor XIII V34L, MTHFR A1298C and C677T and PAI-1 -675 4G/5G) found in CVD panel. The prevalence of these mutations were 0.57, 0.25, 2.61, 13.78, 9.34 and 24.27 % in homozygous form, respectively. Similarly, the mutation percent of them in heterozygous form were 7.43, 3.44, 24.91, 44.94, 41.09 and 45.66%, respectively. No mutation was detected in 92 (1.95%) patients in total. Because of the fact that this is the first study to screen six common mutations in CVD panel in south-east region of Turkey, it has a considerable value on the diagnosis and treatment of these diseases. Upon the results of the present and previous studied a careful examination for these genetic variants should be carried out in thrombophilia screening programs, particularly in Turkish population. PMID:24532105

Oztuzcu, Serdar; Ergun, Sercan; Ula?l?, Mustafa; Nacarkahya, Gülper; I?ci, Yusuf Ziya; I?ci, Mehri; Bayraktar, Recep; Tamer, Ali; Çakmak, Ecir Ali; Arslan, Ahmet

2014-06-01

40

Beyond Luddites and Magicians: Examining the MTR.  

National Technical Information Service (NTIS)

The United States is entering an era that will bring profound changes, and it is unclear what the consequences of the Military Technical Revolution (MTR) may be. Enthusiastic arguments tend to center around 'things, and numbers of things' -- hardware and ...

J. K. McKenzie

1995-01-01

41

SOUTH WING, MTR661, SOUTHWING EXTENSION OF MTR BUILDING. INTERIOR DETAIL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTH WING, MTR-661, SOUTH-WING EXTENSION OF MTR BUILDING. INTERIOR DETAIL INSIDE LAB ROOM 130. CAMERA FACING NORTHEAST. INL NEGATIVE NO. HD46-7-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

42

MTR BUILDING, TRA603. WEST SIDE OF MTR SECOND/THIRD FLOOR AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, TRA-603. WEST SIDE OF MTR SECOND/THIRD FLOOR AND HIGH-BAY REACTOR FLOOR (WITH STAIRWAY FROM ROOF). CAMERA FACING EAST FROM ROOF OF TRA-604. INL NEGATIVE NO. HD46-42-3. Mike Crane, Photographer, April 2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

43

MTR BUILDING, TRA603. NORTH SIDES OF MTR AND PLUG STORAGE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, TRA-603. NORTH SIDES OF MTR AND PLUG STORAGE BUILDINGS. CAMERA FACING SOUTH. INL NEGATIVE NO. HD46-43-4. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

44

MTR plates modeling with MAIA  

SciTech Connect

MAIA is a thermo-mechanical code dedicated to the modeling of MTR fuel plates. The main physical phenomena modeled in the code are the cladding oxidation, the interaction between fuel and Al-matrix, the swelling due to fission products and the Al/fuel particles interaction. The creeping of the plate can be modeled in the mechanical calculation. MAIA has been validated on U-Mo dispersion fuel experiments such as IRIS 1 and 2 and FUTURE. The results are in rather good agreement with post-irradiation examinations. MAIA can also be used to calculate in-pile behavior of U{sub 3}Si{sub 2} plates as in the SHARE experiment irradiated in the SCK/Mol BR2 reactor. The main outputs given by MAIA throughout the irradiation are temperatures, cladding oxidation thickness, interaction thickness, volume fraction of meat constituents, swelling, displacements, strains and stresses. MAIA is originally a two-dimensional code but a three-dimensional version is currently under development. (author)

Marelle, V.; Dubois, S.; Ripert, M.; Noirot, J. [DEN/DEC, CEA Cadarache, 13108 St Paul Lez Durance (France); Lemoine, P. [DEN/DSOE, CEA Saclay, 91191 Gif sur Yvette (France)

2008-07-15

45

Clinically Relevant Mutations that Cause Derepression of the Neisseria gonorrhoeae MtrC-MtrD-MtrE Efflux Pump System Confer Different Levels of Antimicrobial Resistance and In Vivo Fitness  

PubMed Central

Summary The MtrC-MtrD-MtrE efflux pump system confers resistance to macrolide antibiotics and antimicrobial substances of the host innate defense. Clinical isolates with increased resistance to erythromycin and azithromycin frequently harbor mutations in the mtrR structural gene, which encodes a repressor of the mtrCDE operon, or the mtrR promoter region. The MtrC-MtrD-MtrE system is important for gonococcal survival in the murine genital tract, and derepression of the mtrCDE operon via deletion of mtrR confers increased fitness in vivo. Here we compared isogenic strains with naturally occurring mtrR locus mutations for differences in mtrCDE expression and pump-related phenotypes. Mutations upstream of mtrC, including those within the MtrR binding region and a novel mutation that increases mtrC RNA stability conferred the highest levels of derepression as measured by mtrCDE transcription and resistance to antibiotics, progesterone, and antimicrobial peptides. In contrast, mutations within the mtrR coding sequence conferred low to intermediate levels of derepression. In vivo, the mtr mutants were more fit than the wild type strain, the degree to which paralleled in vitro resistance gradients. These studies establish a hierarchy of mtrR locus mutations with regard to regulation of pump efflux, and suggest selection for more derepressed mutants may occur during mixed infections.

Warner, Douglas M.; Shafer, William M.; Jerse, Ann E.

2008-01-01

46

Dueling Regulatory Properties of a Transcriptional Activator (MtrA) and Repressor (MtrR) That Control Efflux Pump Gene Expression in Neisseria gonorrhoeae  

PubMed Central

ABSTRACT MtrA is a member of the AraC family of transcriptional regulators and has been shown to play an important role in enhancing transcription of the mtrCDE operon, which encodes a tripartite multidrug efflux pump, when gonococci are exposed to a sublethal level of antimicrobials. Heretofore, the DNA-binding properties of MtrA were unknown. In order to understand how MtrA activates mtrCDE expression, we successfully purified MtrA and found that it could bind specifically to the mtrCDE promoter region. The affinity of MtrA for the mtrCDE promoter increased 2-fold in the presence of a known effector and substrate of the MtrCDE pump, the nonionic detergent Triton X-100 (TX-100). When placed in competition with MtrR, the transcriptional repressor of mtrCDE, MtrA was found to bind with apparent lower affinity than MtrR to the same region. However, preincubation of MtrA with TX-100 prior to addition of the promoter-containing DNA probe increased MtrA binding and greatly reduced its dissociation from the promoter upon addition of MtrR. Two independent approaches (DNase I footprinting and a screen for bases important in MtrA binding) defined the MtrA-binding site 20–30 bp upstream of the known MtrR-binding site. Collectively, these results suggest that the MtrA and MtrR-binding sites are sterically close and that addition of an effector increases the affinity of MtrA for the mtrCDE promoter such that MtrR binding is negatively impacted. Our results provide a mechanism for transcriptional activation of mtrCDE by MtrA and highlight the complexity of transcriptional control of drug efflux systems possessed by gonococci.

Zalucki, Yaramah M.; Dhulipala, Vijaya; Shafer, William M.

2012-01-01

47

Conceptual Design Studies of a Mono Tiltrotor (MTR) Architecture.  

National Technical Information Service (NTIS)

The Mono Tiltrotor (MTR) is a proposed, innovative heavy-lift rotorcraft architecture. The emerging military strategies most suited to potential application of the MTR are Navy Sea Basing with Ship to Objective Maneuver, and Army Future Combat Systems wit...

J. G. Leishman R. Preator G. D. Baldwin

2004-01-01

48

MTR, SOUTH FACE OF REACTOR. SPECIAL SUPPLEMENTAL SHIELDING WAS REQUIRED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, SOUTH FACE OF REACTOR. SPECIAL SUPPLEMENTAL SHIELDING WAS REQUIRED OUTSIDE OF MTR FOR EXPERIMENTS. THE AIRCRAFT NUCLEAR PROPULSION PROJECT DOMINATED THE USE OF THIS PART OF THE MTR. INL NEGATIVE NO. 7225. Unknown Photographer, 11/28/1952 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

49

MTR BASEMENT. WORKERS (DON ALVORD AND CYRIL VAN ORDEN OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BASEMENT. WORKERS (DON ALVORD AND CYRIL VAN ORDEN OF PHILLIPS PETROLEUM CO.) POSE FOR GAMMA IRRADIATION EXPERIMENT IN MTR CANAL. CANS OF FOOD WILL BE LOWERED TO CANAL BOTTOM, WHERE SPENT MTR FUEL ELEMENTS EMIT GAMMA RADIATION. INL NEGATIVE NO. 11746. Unknown Photographer, 8/20/1954 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

50

MTR coded PRML systems for perpendicular magnetic recording  

NASA Astrophysics Data System (ADS)

We evaluate the BER performance of various MTR coded PRML systems characterized by the polynomials with only positive coefficients in a perpendicular magnetic recording channel using a double-layered medium with jitter-like noise by computer simulation. The results show that {3}/{4} MTR coded PRML systems exhibit good performances compared with {16}/{17} MTR coded PRML systems.

Okamoto, Yoshihiro; Sato, Mitsuteru; Osawa, Hisashi; Saito, Hidetoshi; Muraoka, Hiroaki; Nakamura, Yoshihisa

2001-10-01

51

MTR BUILDING, TRA603. DETAILED VIEW OF NORTHWEST CORNERS OF MTR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, TRA-603. DETAILED VIEW OF NORTHWEST CORNERS OF MTR HIGH-BAY AND SECOND/THIRD STORY SECTIONS. NOTE SHAPE OF PANEL ABOVE WINDOW OVER "TRA-603" BUILDING NUMBERS. THIS IS A "STANDARD PANEL." INL NEGATIVE NUMBER HD46-42-2. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

52

Special Issue: From Mtr to Iter  

Microsoft Academic Search

In 1950, A D Sakharov and I E Tamm put forward the fundamental idea of magnetic thermal confinement of high-temperature plasma, and proposed the magnetic thermonuclear reactor (MTR) concept. Studies in this direction initiated the mammoth 'Tokamak' programme. After many years of persistent scientific and engineering efforts in many countries worldwide, the realisation of the thermonuclear reaction has now become

Boris B. Kadomtsev

1996-01-01

53

Folate metabolism polymorphisms influence risk of colorectal adenoma recurrence.  

PubMed

Folate intake is inversely related to risk of developing colorectal neoplasia. Associations between risk of colorectal neoplasia and polymorphisms in genes coding for enzymes involved in folate metabolism have also been reported, suggesting a relationship between genotype and development of colorectal neoplasia. To further investigate the effects of folate metabolism genotypes on colorectal neoplasia, we genotyped 546 patients participating in a randomized controlled trial of folate supplementation for the prevention of colorectal adenoma recurrence. A significantly reduced risk of recurrence was observed in patients heterozygous for the MTRR A66G polymorphism [relative risk (RR), 0.64; 95% confidence interval (95% CI), 0.46-0.90] or heterozygous for the MTHFR A1298C polymorphism (RR, 0.71; 95% CI, 0.52-0.97). Furthermore, a significant reduction in recurrence risk was seen in MTRR A66G heterozygotes who received folate supplements but not in those who did not receive folate. Patients heterozygous for the MTHFR C677T polymorphism had a nonsignificant risk reduction (RR, 0.92; 95% CI, 0.69-1.23), as did patients with one or two variant alleles for the MTR A2756G polymorphism (RR, 0.82; 95% CI, 0.60-1.12). No influence on recurrence risk was observed for the TSER, TSER 3R G>C, and TS 1494del6 variants. These findings provide additional support for the hypothesis that germ line variants in folate metabolism genes influence the development of colorectal adenomas. PMID:16985020

Hubner, Richard A; Muir, Kenneth R; Liu, Jo-Fen; Sellick, Gabrielle S; Logan, Richard F A; Grainge, Matthew; Armitage, Nicholas; Chau, Ian; Houlston, Richard S

2006-09-01

54

Polymorphisms in Methionine Synthase, Methionine Synthase Reductase and Serine Hydroxymethyltransferase, Folate and Alcohol Intake, and Colon Cancer Risk  

PubMed Central

Background/Aims We examined associations among folate and alcohol intake, SNPs in genes involved in one-carbon metabolism and colon cancer risk. Methods Colon cancer cases (294 African Americans and 349 whites) were frequency matched to population controls (437 African Americans and 611 whites) by age, race and sex from 33 North Carolina counties from 1996 to 2000. Folate and alcohol intakes were collected by dietary interview. Five SNPs were genotyped using DNA from whole blood: SHMT C1420T; MTRR A66G; MTR A2756G, and the previously-reported MTHFR C677T and MTHFR A1298C. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression. Results An inverse association was observed for SHMT TT genotype as compared to CC genotype in whites (OR=0.6, 95%CI=0.4, 1.0), but not in African Americans. Inverse associations were observed for high folate intake in individuals carrying 0 or 1 variant allele [OR 0.2 (95%CI 0.06 – 0.8) for African Americans; OR 0.2 (95%CI 0.1– 0.6) for whites] compared to low folate intake. Modest interactions between these SNPs and alcohol or folate intakes were observed. Conclusions Our results are consistent with other findings and provide needed data on these associations among African Americans.

Steck, Susan E.; Keku, Temitope; Butler, Lesley M.; Galanko, Joseph; Massa, Beri; Millikan, Robert C.; Sandler, Robert S.

2009-01-01

55

Gamma measurements on MTR fuel assemblies  

SciTech Connect

Fuel for Material Test Reactors (MTRs) presents an interesting and challenging problem for International Atomic Energy Agency (IAEA) inspectors. Most such reactors use fuel which was made from high enriched uranium (/sup 235/U greater than or equal to 20%). The fuel is in the form of an uranium-aluminium alloy and is considered direct use material. This type fuel is found in two types of facilities, fuel fabrication plants and at the reactors themselves. While the fabrication plants normally have large inventories of MTR assemblies, individual reactor sites have small but often significant quantities of fuel material. The gamma ray measurement of fuel assemblies for safeguards purposes is the topic of this paper. The methods described use computer codes to calculate predicted count rates considering detector-assembly coupling including assembly self-absorption and buildup. Results of actual measurements and estimates of measurement uncertainties are given for both rectangular and cylindrical MTR fuel elements.

Abedin-Zadeh, R.; Halbig, J.; Schreiber, H.J.

1987-07-01

56

ETR AND MTR COMPLEXES IN CONTEXT. CAMERA FACING NORTHERLY. FROM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR AND MTR COMPLEXES IN CONTEXT. CAMERA FACING NORTHERLY. FROM BOTTOM TO TOP: ETR COOLING TOWER, ELECTRICAL BUILDING AND LOW-BAY SECTION OF ETR BUILDING, HEAT EXCHANGER BUILDING (WITH U SHAPED YARD), COMPRESSOR BUILDING. MTR REACTOR SERVICES BUILDING IS ATTACHED TO SOUTH WALL OF MTR. WING A IS ATTACHED TO BALCONY FLOOR OF MTR. NEAR UPPER RIGHT CORNER OF VIEW IS MTR PROCESS WATER BUILDING. WING B IS AT FAR WEST END OF COMPLEX. NEAR MAIN GATE IS GAMMA FACILITY, WITH "COLD" BUILDINGS BEYOND: RAW WATER STORAGE TANKS, STEAM PLANT, MTR COOLING TOWER PUMP HOUSE AND COOLING TOWER. INL NEGATIVE NO. 56-4101. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

57

33 CFR 154.1041 - Specific response information to be maintained on mobile MTR facilities.  

Code of Federal Regulations, 2010 CFR

...Specific response information to be maintained on mobile MTR facilities. 154.1041 Section 154.1041...Specific response information to be maintained on mobile MTR facilities. (a) Each mobile MTR facility must carry the following information...

2009-07-01

58

33 CFR 154.1041 - Specific response information to be maintained on mobile MTR facilities.  

Code of Federal Regulations, 2013 CFR

...Specific response information to be maintained on mobile MTR facilities. 154.1041 Section 154.1041...Specific response information to be maintained on mobile MTR facilities. (a) Each mobile MTR facility must carry the following information...

2013-07-01

59

33 CFR 154.1041 - Specific response information to be maintained on mobile MTR facilities.  

Code of Federal Regulations, 2010 CFR

...Specific response information to be maintained on mobile MTR facilities. 154.1041 Section 154.1041...Specific response information to be maintained on mobile MTR facilities. (a) Each mobile MTR facility must carry the following information...

2010-07-01

60

MATERIALS TESTING REACTOR (MTR) BUILDING, TRA603. CONTEXTUAL VIEW OF MTR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MATERIALS TESTING REACTOR (MTR) BUILDING, TRA-603. CONTEXTUAL VIEW OF MTR BUILDING SHOWING NORTH SIDES OF THE HIGH-BAY REACTOR BUILDING, ITS SECOND/THIRD FLOOR BALCONY LEVEL, AND THE ATTACHED ONE-STORY OFFICE/LABORATORY BUILDING, TRA-604. CAMERA FACING SOUTHEAST. VERTICAL CONCRETE-SHROUDED BEAMS SUPPORT PRECAST CONCRETE PANELS. CONCRETE PROJECTION FORMED AS A BUNKER AT LEFT OF VIEW IS TRA-657, PLUG STORAGE BUILDING. INL NEGATIVE NO. HD46-42-1. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

61

Analysis of Structural MtrC Models Based on Homology with the Crystal Structure of MtrF  

SciTech Connect

The outer-membrane decahaem cytochrome MtrC is part of the transmembrane MtrCAB complex required for mineral respiration by Shewanella oneidensis. MtrC has significant sequence similarity to the paralogous decahaem cytochrome MtrF, which has been structurally solved through X-ray crystallography. This now allows for homology-based models of MtrC to be generated. The structure of these MtrC homology models contain ten bis-histidine-co-ordinated c-type haems arranged in a staggered cross through a four-domain structure. This model is consistent with current spectroscopic data and shows that the areas around haem 5 and haem 10, at the termini of an octahaem chain, are likely to have functions similar to those of the corresponding haems in MtrF. The electrostatic surfaces around haem 7, close to the ?-barrels, are different in MtrF and MtrC, indicating that these haems may have different potentials and interact with substrates differently.

Edwards, Marcus; Fredrickson, Jim K.; Zachara, John M.; Richardson, David; Clarke, Thomas A.

2012-12-01

62

MTR BUILDING AND BALCONY FLOORS. CAMERA FACING EASTERLY. PHOTOGRAPHER DID ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING AND BALCONY FLOORS. CAMERA FACING EASTERLY. PHOTOGRAPHER DID NOT EXPLAIN DARK CLOUD. MTR WING WILL ATTACH TO GROUND FLOOR. INL NEGATIVE NO. 1567. Unknown Photographer, 2/28/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

63

CONCEPTUAL DESIGN STUDIES OF A MONO TILTROTOR (MTR) ARCHITECTURE  

Microsoft Academic Search

The Mono Tiltrotor (MTR) is a proposed, innovative heavy-lift rotorcraft architecture. Its capabilities are predi- cated on the combination of an advanced coaxial rotor sys- tem and sophisticated kinematics that morph the aircraft topology for efficient flight over the entire operational en- velope. The MTR rotorcraft integrates a coaxial rotor, a folding lifting wing system, a lightweight airframe and an

Robin Preator; J. Gordon Leishman; G. Douglas Baldwin

64

Time-varying MTR codes for high density magnetic recording  

Microsoft Academic Search

Maximal transition run (MTR) codes eliminate the dominant error-event in high density magnetic recording by allowing at most two consecutive magnetic transitions. The maximum rate of such a code is upper bounded by the Shannon capacity 0.879. Unfortunately, the coding gain for MTR codes has not proven to be very significant since the distance benefit due to removing the dominant

K. Knudson Fitzpatrick; Cory S. Modlin

1997-01-01

65

MTR CANAL IS FILLED WITH WATER. MAN STANDS ON MOVABLE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR CANAL IS FILLED WITH WATER. MAN STANDS ON MOVABLE BRIDGE. NOTE CHAINS AND HOOK AT LEFT. THIS SECTION OF CANAL PROJECTED EAST BEYOND THE SITE OF THE MTR BUILDING. INL NEGATIVE NO. 6003. Unknown Photographer, 6/16/1952 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

66

REACTIVITY MEASUREMENT FACILITY, UNDER CONSTRUCTION OVER MTR CANAL IN BASEMENT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

REACTIVITY MEASUREMENT FACILITY, UNDER CONSTRUCTION OVER MTR CANAL IN BASEMENT OF MTR BUILDING, TRA-603. WOOD PLANKS REST ON CANAL WALL OBSERVABLE IN FOREGROUND. INL NEGATIVE NO. 11745. Unknown Photographer, 8/20/1954 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

67

PRECONSTRUCTION IMAGE OF THE MTR SITE. ABANDONED IRRIGATION CANAL (FROM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PRE-CONSTRUCTION IMAGE OF THE MTR SITE. ABANDONED IRRIGATION CANAL (FROM EARLY 1900s) ILLUSTRATES FLATNESS OF MTR/TRA TERRAIN. FEATURE ON HORIZON IN LEFT OF VIEW IS EXPLORATORY WATER DRILLING EQUIPMENT. CAMERA LOOKS SOUTHEAST. INL NEGATIVE NO. 136. Unknown Photographer, 12/5/1949 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

68

PRECAST CONCRETE WALL PANELS ARE LIFTED INTO PLACE ON MTR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PRECAST CONCRETE WALL PANELS ARE LIFTED INTO PLACE ON MTR STEEL FRAME STRUCTURE. INL NEGATIVE NO. 1330. Unknown Photographer, 1/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

69

MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION EXPERIMENT NO. 1. INL NEGATIVE NO. 6510. Unknown Photographer, 9/29/1959 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

70

TOP OF MTR. CONTROL RODS AND GRID PLATE EMERGE FROM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

TOP OF MTR. CONTROL RODS AND GRID PLATE EMERGE FROM REACTOR TANK. INL NEGATIVE NO. 6206. R.G. Larsen, Photographer, 6/27/1952 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

71

Clinically feasible MTR is sensitive to cortical demyelination in MS  

PubMed Central

Objective: Presently there is no clinically feasible imaging modality that can effectively detect cortical demyelination in patients with multiple sclerosis (MS). The objective of this study is to determine if clinically feasible magnetization transfer ratio (MTR) imaging is sensitive to cortical demyelination in MS. Methods: MRI were acquired in situ on 7 recently deceased patients with MS using clinically feasible sequences at 3 T, including relatively high-resolution T1-weighted and proton density–weighted images with/without a magnetization transfer pulse for calculation of MTR. The brains were rapidly removed and placed in fixative. Multiple cortical regions from each brain were immunostained for myelin proteolipid protein and classified as mostly myelinated (MMctx), mostly demyelinated (MDctx), or intermediately demyelinated (IDctx). MRIs were registered with the cortical sections so that the cortex corresponding to each cortical section could be identified, along with adjacent subcortical white matter (WM). Mean cortical MTR normalized to mean WM MTR was calculated for each cortical region. Linear mixed-effects models were used to test if mean normalized cortical MTR was significantly lower in demyelinated cortex. Results: We found that mean normalized cortical MTR was significantly lower in cortical tissue with any demyelination (IDctx or MDctx) compared to MMctx (demyelinated cortex: least-squares mean [LSM] = 0.797, SE = 0.007; MMctx: LSM = 0.837, SE = 0.006; p = 0.01, n = 89). Conclusions: This result demonstrates that clinically feasible MTR imaging is sensitive to cortical demyelination and suggests that MTR will be a useful tool to help detect MS cortical lesions in living patients with MS.

Chen, Jacqueline Tien-Hsiang; Easley, Kathryn; Schneider, Colleen; Nakamura, Kunio; Kidd, Grahame J.; Chang, Ansi; Staugaitis, Susan M.; Fox, Robert J.; Fisher, Elizabeth; Arnold, Douglas L.; Trapp, Bruce D.

2013-01-01

72

A1298C polymorphism in the MTHFR gene predisposes to cardiovascular risk in rheumatoid arthritis  

Microsoft Academic Search

INTRODUCTION: We determined the contribution of the methylene tetrahydrofolate reductase (MTHFR) 677 C>T and 1298 A>C gene polymorphisms to the susceptibility to rheumatoid arthritis (RA). We also assessed whether these two MTHFR gene polymorphisms may be implicated in the development of cardiovascular (CV) events and subclinical atherosclerosis manifested by the presence of endothelial dysfunction, in a series of Spanish patients

Rogelio Palomino-Morales; Carlos Gonzalez-Juanatey; Tomas R Vazquez-Rodriguez; Luis Rodriguez; Jose A Miranda-Filloy; Benjamin Fernandez-Gutierrez; Javier Llorca; Javier Martin; Miguel A Gonzalez-Gay

2010-01-01

73

A1298C polymorphism in the MTHFR gene predisposes to cardiovascular risk in rheumatoid arthritis  

PubMed Central

Introduction We determined the contribution of the methylene tetrahydrofolate reductase (MTHFR) 677 C>T and 1298 A>C gene polymorphisms to the susceptibility to rheumatoid arthritis (RA). We also assessed whether these two MTHFR gene polymorphisms may be implicated in the development of cardiovascular (CV) events and subclinical atherosclerosis manifested by the presence of endothelial dysfunction, in a series of Spanish patients with RA. Methods Six hundred and twelve patients fulfilling the 1987 American College of Rheumatology classification criteria for RA, seen at the rheumatology outpatient clinics of Hospital Xeral-Calde, Lugo and Hospital San Carlos, Madrid, were studied. Patients and controls (n = 865) were genotyped using predesigned TaqMan SNP genotyping assays. Results No significant differences in allele or genotype frequencies for the MTHFR gene polymorphisms between RA patients and controls were found. Also, no association between the MTHFR 677 C>T polymorphism and CV events or endothelial dysfunction was observed. However, the MTHFR 1298 allele C frequency was increased in patients with CV events after 5 years (38.7% versus 30.3%; odds ratio = 1.45; 95% confidence interval = 1.00 to 2.10; P = 0.04) and 10 years (42.2% versus 31.0%; odds ratio = 1.62; 95% confidence interval = 1.08 to 2.43; P = 0.01) follow up. Moreover, patients carrying the MTHFR 1298 AC and CC genotypes had a significantly decreased flow-mediated endothelium-dependent vasodilatation (4.3 ± 3.9%) compared with those carrying the MTHFR 1298 AA genotype (6.5 ± 4.4%) (P = 0.005). Conclusions Our results show that the MTHFR 1298 A>C gene polymorphism confers an increased risk for subclinical atherosclerosis and CV events in patients with RA.

2010-01-01

74

CONTROL ROOM ON MARCH 31, 1952, AS THE MTR GOES ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CONTROL ROOM ON MARCH 31, 1952, AS THE MTR GOES CRITICAL FOR THE FIRST TIME. COMPARE CEILING FIXTURES IN THIS PHOTO AND PHOTO ID-33-G-212 FOR COMMON PERSPECTIVE. INL NEGATIVE NO. 4517. Unknown Photographer, 3/31/1952 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

75

CANAL EMERGES FROM EAST SIDE OF MTR BUILDING. "EXTRA" LENGTH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CANAL EMERGES FROM EAST SIDE OF MTR BUILDING. "EXTRA" LENGTH WAS TO STORE SPENT FUEL THAT WOULD ACCUMULATE BEFORE THE CHEMICAL PROCESSING PLANT WAS READY TO PROCESS IT. INL NEGATIVE NO. 1659. Unknown Photographer, 3/9/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

76

Low complexity signal space detection for MTR coded channels  

Microsoft Academic Search

Two new signal space detectors designed to take advantage of maximum transition run (MTR) coded modulation are presented. These detectors are designed to perform across a wide range of densities and offer lower error rates than a 3D-110 detector at low densities while requiring only modest increases in complexity. The first scheme, 2D-121? employs an equalization constraint that reduces low

Barrett Brickner; Jaekyun Moon

1998-01-01

77

Pedestrian route choices between escalator and stairway in MTR stations  

Microsoft Academic Search

Passenger demands on underground stations are always excessive and can cause severe congestion. The study of pedestrian behavior is particularly important in planning and design of the underground stations during peak hours. This paper reports an investigation on the behavior of pedestrians in choosing between escalators and stairways in Hong Kong Mass Transit Railway (MTR) stations during peak hours. Time-lapse

C. Y. Cheung; William H. K. Lam

1998-01-01

78

Harmonic simulation of MTR traction system by EMTP  

Microsoft Academic Search

The proliferation of nonlinear loads resulting from new technologies has increased the levels of harmonics in power systems, and traction systems represent large nonlinear loads. This paper presents results of a simulation and site measurement study of the harmonics related to Mass Transit Railway (MTR) in Hong Kong. Simulation results from the ATP Electromagnetic Transient Program (EMTP) are compared with

Laurence Snider; Edward Lo; Terrance Lai

1999-01-01

79

Thermal-hydraulic modeling of reactivity accident in MTR reactors  

Microsoft Academic Search

This paper describes the development of a dynamic model for the thermal-hydraulic analysis of MTR research reactor during a reactivity insertion accident (RIA). The model is formulated for coupling reactor kinetics with feedback reactivity and the reactor core thermal-hydraulics. Two channels are considered: the average and the hot channels to represent the reactor core. The developed computer program is compiled

Hany Khater; Talal Abu-EL-Maty; Salah El-Din EL-Morshdy

2007-01-01

80

CUTS FOR MTR EXCAVATION ILLUSTRATE SEDIMENTARY MANTLE OF SOIL AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CUTS FOR MTR EXCAVATION ILLUSTRATE SEDIMENTARY MANTLE OF SOIL AND GRAVEL OVERLAYING LAVA ROCK FIFTY FEET BELOW. SAGEBRUSH HAS BEEN SCOURED FROM REST OF SITE. CAMERA PROBABLY FACES SOUTHWEST. INL NEGATIVE NO. 67. Unknown Photographer, 6/4/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

81

The mtr Locus is a Two-Gene Operon Required for Transcription Attenuation in the trp Operon of Bacillus subtilis  

Microsoft Academic Search

We have cloned and characterized the mtr operon of Bacillus subtilis. This operon encodes a presumed RNA-binding regulatory protein that is required for attenuation control of the trp operon. We have shown that the mtr operon consists of two structural genes, mtrA and mtrB, predicted to encode 22-kDa and 8-kDa polypeptides, respectively. MtrB shows homology with RegA, and RNA-binding regulatory

Paul Gollnick; Shuichi Ishino; Mitzi I. Kuroda; Dennis J. Henner; Charles Yanofsky

1990-01-01

82

MTR MAIN FLOOR. NEUTRON TUNNEL (SPANNED BY STILELIKE STEPS) PROJECTS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR MAIN FLOOR. NEUTRON TUNNEL (SPANNED BY STILE-LIKE STEPS) PROJECTS FROM THE SOUTHEAST CORNER OF THE MTR TOWARD SOUTHEAST CORNER OF BUILDING, WHERE SHIELDING BLOCKS BEGIN TO SURROUND THE TUNNEL AS IT NEARS DETECTING INSTRUMENTS NEAR THE BUILDING WALL. GEAR RELATED TO CRYSTAL NEUTRON SPECTROMETER IS IN FOREGROUND SURROUNDED BY SHIELDING. DATA CONSOLES ARE AT MID-LEVEL OF EAST FACE. OTHER WORK PROCEEDS ON TOP OF AND ELSEWHERE AROUND REACTOR. NOTE TOOLS HANGING AGAINST SOUTHEAST CORNER, USED TO CHANGE FUEL ELEMENTS AND OTHER REACTOR ITEMS DURING REFUELING CYCLES. INL NEGATIVE NO. 10439. Unknown Photographer, 4/20/1954 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

83

TOP OF MTR. MAN CLIMBS FRAME ON FOOT LADDER TO ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

TOP OF MTR. MAN CLIMBS FRAME ON FOOT LADDER TO POSITION CRANE HOOK, WHICH WILL LIFT TOP PLUG FROM REACTOR AS A STEP IN REFUELING PROCEDURES. NOTE CRANE OPERATOR AT UPPER LEFT OF VIEW. ENTIRE APPARATUS, INCLUDING FRAME AND DRIVES FOR CONTROL RODS, WILL BE LIFTED. INL NEGATIVE NO. 6199. R.G. Larsen, Photographer, 6/22/1952 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

84

CONTROL CONSOLE FOR MTR FISSION PRODUCT MONITOR, USED TO DETECT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CONTROL CONSOLE FOR MTR FISSION PRODUCT MONITOR, USED TO DETECT BREAKS IN CLADDING OF FUEL ELEMENTS. COUNT-RATE METER IN TOP PANEL INDICATES AMOUNT OF RADIOACTIVITY. LOWER PANELS SUPPLY POWER AND AMPLIFICATION OF SIGNALS GENERATED BY SCINTILLATION COUNTER/PHOTOMULTIPLIER TUBE COMBINATION IN RESPONSE TO RADIOACTIVITY IN A SAMPLE OF THE COOLING WATER. INL NEGATIVE NO. 56-771. Jack L. Anderson, Photographer, 3/15/1956. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

85

MTR BASEMENT. DOORWAY TO SOURCE STORAGE VAULT IS AT CENTER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BASEMENT. DOORWAY TO SOURCE STORAGE VAULT IS AT CENTER OF VIEW; TO DECONTAMINATION ROOM, AT RIGHT. PART OF MAZE ENTRY IS VISIBLE INSIDE VAULT DOORWAY. INL NEGATIVE NO. 7763. Unknown Photographer, photo was dated as 3/30/1953, but this was probably an error. The more likely date is 3/30/1952. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

86

MTR CAISSONS WERE DRILLED INTO BEDROCK. IN CENTER OF VIEW, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR CAISSONS WERE DRILLED INTO BEDROCK. IN CENTER OF VIEW, CONCRETE FLOWS FROM TRUCK INTO DRUM, WHICH IS LOWERED INTO CAISSON AND RELEASED AT BOTTOM OF HOLE. BEYOND, TRUCK-MOUNTED DRILLING RIG DRILLS HOLE FOR ANOTHER CAISSON NEAR EDGE OF EXCAVATION. MATERIAL REMOVED FROM HOLE IS CARRIED BY CONVEYOR TO WAITING TRUCK. INL NEGATIVE NO. 307. Unknown Photographer, 6/1950. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

87

Gamma-ray spectroscopy on irradiated MTR fuel elements  

Microsoft Academic Search

The availability of burnup data is an important requirement in any systematic approach to the enhancement of safety, economics and performance of a nuclear research reactor. This work presents the theory and experimental techniques applied to determine, by means of nondestructive gamma-ray spectroscopy, the burnup of Material Testing Reactor (MTR) fuel elements irradiated in the IEA-R1 research reactor. Burnup measurements,

L. A. A Terremoto; C. A Zeituni; J. A Perrotta; J. E. R da Silva

2000-01-01

88

Reduced MTR in the corticospinal tract and normal T 2 in amyotrophic lateral sclerosis  

Microsoft Academic Search

The objective of this study was to test the hypothesis that magnetization transfer ratios (MTR) are decreased in the corticospinal tract of patients with amyotrophic lateral sclerosis (ALS); to determine if T2 is increased in corticospinal tract or reduced in motor cortex in ALS; to determine if corticospinal tract MTR correlates with a clinical measure of motor neuron function in

Jody L Tanabe; Martina Vermathen; Robert Miller; Deborah Gelinas; Michael W Weiner; William D Rooney

1998-01-01

89

MTR WING A, TRA604. NORTH SIDE. CAMERA FACING SOUTH. OFFICE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604. NORTH SIDE. CAMERA FACING SOUTH. OFFICE WING IS CONNECTED TO TRA-603 SECOND/THIRD FLOOR AT LEFT. PROJECTION AT RIGHT IS TRA-668, MTR NORTH WING EXTENSION. INL NEGATIVE NO. HD47-44-2. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

90

Thermal–hydraulic modeling of the onset of flow instability in MTR reactors  

Microsoft Academic Search

Prediction of the onset of the flow instability (OFI) in steady and transient sub-cooled flow boiling is an important consideration in the design and operation of nuclear reactors, in particular for materials testing reactors (MTR). In this study, a predictive model for OFI in the MTR has been developed. The model is based on both the heat balance during the

Hany A. Khater; Salah El-Din El-Morshedy; Mohamed M. A. Ibrahim

2007-01-01

91

MTR STACK, TRA710, CONTEXTUAL VIEW AFTER ETR STACK HAD BEEN ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR STACK, TRA-710, CONTEXTUAL VIEW AFTER ETR STACK HAD BEEN DEMOLISHED. CAMERA FACING NORTHWEST. MTR BUILDING IS AT LEFT EDGE OF VIEW. INL NEGATIVE NO. HD52-1-4. Mike Crane, Photographer, 5/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

92

MTR WING, TRA604. SECTIONS A, B, AND C SHOW CORRIDOR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING, TRA-604. SECTIONS A, B, AND C SHOW CORRIDOR ARRANGEMENTS AND CONNECTIONS TO MTR BUILDING. BLAW-KNOX 3150-804-6, 11/1950. INL INDEX NO. 531-0604-00-098-100631, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

93

Spontaneous Mutation at the mtr Locus of Neurospora: The Spectrum of Mutant Types  

Microsoft Academic Search

We have isolated 135 strains of Neurospora which have mutations at the mtr locus resulting from independent spontaneous events. mtr is the structural gene for the neutral amino acid permease. The mutants have been characterized by their reversion behavior (both spontaneous and induced) and by hybridization studies of restriction digests of their DNA. About half of the mutants (54%) appear

David Stadler; Helen Macleod; Davin Dillon

94

MTR, TRA603. BASEMENT DECONTAMINATION ROOM DETAILS. WALLS OF SOLID CONCRETE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, TRA-603. BASEMENT DECONTAMINATION ROOM DETAILS. WALLS OF SOLID CONCRETE MASONRY. STAINLESS STEEL WORK BENCH, FLOOR COVING AND DRAINS. "WARM" FLOOR DRAIN. OVERHEAD SHOWER WITH CHAIN PULL. IDO MTR-603-IDO-4, 12/1952. INL INDEX NO. 531-0603-00-396-110468, REV. 1. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

95

MTR WING A, TRA604. SOUTH SIDE, LARGELY HIDDEN BY TEMPORARY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604. SOUTH SIDE, LARGELY HIDDEN BY TEMPORARY STORAGE STRUCTURE. CAMERA FACING NORTHWEST. EAST SIDE OF TRA-661, MTR SOUTH WING IS AT LEFT OF VIEW. INL NEGATIVE NO. HD47-44-4. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

96

MTR BUILDING INTERIOR, TRA603. BASEMENT. CAMERA IN WEST CORRIDOR FACING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. BASEMENT. CAMERA IN WEST CORRIDOR FACING SOUTH. FREIGHT ELEVATOR IS AT RIGHT OF VIEW. AT CENTER VIEW IS MTR VAULT NO. 1, USED TO STORE SPECIAL OR FISSIONABLE MATERIALS. INL NEGATIVE NO. HD46-6-3. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

97

Assessment of myofascial trigger points (MTrPs): a new application of ultrasound imaging and vibration sonoelastography.  

PubMed

Myofascial trigger points (MTrPs) are palpable hyperirritable nodules in skeletal muscle that are associated with chronic musculoskeletal pain. The goal of this study was to image MTrPs in the upper trapezius muscle using 2D gray scale ultrasound (US) and vibration sonoelastography (VSE) for differentiating the soft tissue characteristics of MTrPs compared to surrounding muscle. MTrPs appeared as hypoechoeic elliptically-shaped focal regions within the trapezius muscle on 2D US. Audio-frequency vibrations (100-250 Hz) were induced in the trapezius muscle of four volunteers with clinically identifiable MTrPs, and the induced vibration amplitudes were imaged using the color Doppler variance mode, and were further quantified using spectral Doppler analysis. Spectral Doppler analysis showed that vibration amplitudes were 27% lower on average within the MTrP compared to surrounding tissue (p0.05). Color variance imaging consistently detected a focal region of reduced vibration amplitude, which correlated with the hypoechoeic region identified as an MTrP (r =0.76 for area). Real-time 2D US identifies MTrPs, and VSE is feasible for differentiating MTrPs from surrounding tissue. Preliminary findings show that MTrPs are hypoechoeic on 2D US and the relative stiffness of MTrPs can be quantified using VSE. Ultrasound offers a convenient, accessible and low-risk approach for identifying MTrPs and for evaluating clinical observations of palpable, painful nodules. PMID:19163983

Sikdar, Siddhartha; Shah, Jay P; Gilliams, Elizabeth; Gebreab, Tadesse; Gerber, Lynn H

2008-01-01

98

CONCRETE POURS HAVE PRODUCED A REINFORCED SUPPORT BASE FOR MTR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CONCRETE POURS HAVE PRODUCED A REINFORCED SUPPORT BASE FOR MTR REACTOR. PIPE TUNNEL IS UNDER CONSTRUCTION AT CENTER OF VIEW. PIPES WILL CARRY RADIOACTIVE WATER FROM REACTOR TO WATER PROCESS BUILDING. CAMERA LOOKS SOUTH INTO TUNNEL ALONG WEST SIDE OF REACTOR BASE. TWO CAISSONS ARE AT LEFT SIDE OF VIEW. NOTE "WINDOW" IN SOUTH FACE OF REACTOR BASE AND ALSO GROUP OF PENETRATIONS TO ITS LEFT. INL NEGATIVE NO. 733. Unknown Photographer, 10/6/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

99

Failed MTR Fuel Element Detect in a Sipping Tests  

SciTech Connect

This work describes sipping tests performed on Material Testing Reactor (MTR) fuel elements of the IEA-R1 research reactor, in order to find out which one failed in the core during a routine operation. Radioactive iodine isotopes {sup 131}I and {sup 133}I, employed as failure monitors, were detected in samples corresponding to the failed fuel element. The specific activity of each sample, as well as the average leaking rate, were measured for {sup 137}Cs. The nuclear fuels U{sub 3}O{sub 8} - Al dispersion and U - Al alloy were compared concerning their measured average leaking rates of {sup 137}Cs.

Zeituni, C.A.; Terremoto, L.A.A.; da Silva, J.E.R.

2004-10-06

100

WORKERS FABRICATE ROOF SLABS FOR MTR BUILDING AT THE CONSTRUCTION ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

WORKERS FABRICATE ROOF SLABS FOR MTR BUILDING AT THE CONSTRUCTION SITE. FORMS WERE MADE OF STEEL. AFTER AN INCH OF CONCRETE HAD BEEN POURED IN THE FORM, A MAT OF REINFORCING STEEL WAS PLACED ON IT. THE REMAINDER OF THE FORM WAS FILLED, AND THE CONCRETE WAS VIBRATED, STRUCK, AND TROWELED. GROOVES AT CORNER WILL HAVE 1/4 INCH RODS WELDED INTO THE EYE OF THE STEEL MAT FOR GROUNDING. INL NEGATIVE NO. 578. Unknown Photographer, 9/1/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

101

Crystal Structure of the Open State of the Neisseria gonorrhoeae MtrE Outer Membrane Channel.  

PubMed

Active efflux of antimicrobial agents is one of the most important strategies used by bacteria to defend against antimicrobial factors present in their environment. Mediating many cases of antibiotic resistance are transmembrane efflux pumps, composed of one or more proteins. The Neisseria gonorrhoeae MtrCDE tripartite multidrug efflux pump, belonging to the hydrophobic and amphiphilic efflux resistance-nodulation-cell division (HAE-RND) family, spans both the inner and outer membranes of N. gonorrhoeae and confers resistance to a variety of antibiotics and toxic compounds. We here describe the crystal structure of N. gonorrhoeae MtrE, the outer membrane component of the MtrCDE tripartite multidrug efflux system. This trimeric MtrE channel forms a vertical tunnel extending down contiguously from the outer membrane surface to the periplasmic end, indicating that our structure of MtrE depicts an open conformational state of this channel. PMID:24901251

Lei, Hsiang-Ting; Chou, Tsung-Han; Su, Chih-Chia; Bolla, Jani Reddy; Kumar, Nitin; Radhakrishnan, Abhijith; Long, Feng; Delmar, Jared A; Do, Sylvia V; Rajashankar, Kanagalaghatta R; Shafer, William M; Yu, Edward W

2014-01-01

102

Crystal Structure of the Open State of the Neisseria gonorrhoeae MtrE Outer Membrane Channel  

PubMed Central

Active efflux of antimicrobial agents is one of the most important strategies used by bacteria to defend against antimicrobial factors present in their environment. Mediating many cases of antibiotic resistance are transmembrane efflux pumps, composed of one or more proteins. The Neisseria gonorrhoeae MtrCDE tripartite multidrug efflux pump, belonging to the hydrophobic and amphiphilic efflux resistance-nodulation-cell division (HAE-RND) family, spans both the inner and outer membranes of N. gonorrhoeae and confers resistance to a variety of antibiotics and toxic compounds. We here describe the crystal structure of N. gonorrhoeae MtrE, the outer membrane component of the MtrCDE tripartite multidrug efflux system. This trimeric MtrE channel forms a vertical tunnel extending down contiguously from the outer membrane surface to the periplasmic end, indicating that our structure of MtrE depicts an open conformational state of this channel.

Bolla, Jani Reddy; Kumar, Nitin; Radhakrishnan, Abhijith; Long, Feng; Delmar, Jared A.; Do, Sylvia V.; Rajashankar, Kanagalaghatta R.; Shafer, William M.; Yu, Edward W.

2014-01-01

103

Gamma-ray spectroscopy on irradiated MTR fuel elements  

NASA Astrophysics Data System (ADS)

The availability of burnup data is an important requirement in any systematic approach to the enhancement of safety, economics and performance of a nuclear research reactor. This work presents the theory and experimental techniques applied to determine, by means of nondestructive gamma-ray spectroscopy, the burnup of Material Testing Reactor (MTR) fuel elements irradiated in the IEA-R1 research reactor. Burnup measurements, based on analysis of spectra that result from collimation and detection of gamma-rays emitted in the decay of radioactive fission products, were performed at the reactor pool area. The measuring system consists of a high-purity germanium (HPGe) detector together with suitable fast electronics and an on-line microcomputer data acquisition module. In order to achieve absolute burnup values, the detection set (collimator tube+HPGe detector) was previously calibrated in efficiency. The obtained burnup values are compared with ones provided by reactor physics calculations, for three kinds of MTR fuel elements with different cooling times, initial enrichment grades and total number of fuel plates. Both values show good agreement within the experimental error limits.

Terremoto, L. A. A.; Zeituni, C. A.; Perrotta, J. A.; da Silva, J. E. R.

2000-08-01

104

Pedestrian route choices between escalator and stairway in MTR stations  

SciTech Connect

Passenger demands on underground stations are always excessive and can cause severe congestion. The study of pedestrian behavior is particularly important in planning and design of the underground stations during peak hours. This paper reports an investigation on the behavior of pedestrians in choosing between escalators and stairways in Hong Kong Mass Transit Railway (MTR) stations during peak hours. Time-lapse photography surveys were conducted in six selected MTR stations to collect the relevant data. The travel time functions of the vertical pedestrian facilities have been calibrated and are used for developing the pedestrian route choice model. Service levels have been defined for the vertical pedestrian facilities based upon the service levels defined by previous researchers. It was found that the stairway capacities in the ascending and descending directions in the Hong Kong Mass Transit Railway stations are higher than in London Underground stations. It was also found that the pedestrians are more sensitive to the relative delays when using the vertical pedestrian facilities in the descending direction than in the ascending direction.

Cheung, C.Y.; Lam, W.H.K. [Hong Kong Polytechnic Univ., Hung Hom (Hong Kong). Dept. of Civil and Structural Engineering

1998-05-01

105

Decontamination and decommissioning MTR-657 plug storage facility. Final report  

SciTech Connect

The MTR-657 Plug Storage Facility consists of 32 horizontal shielded storage holes. Two of these holes contained contaminated hardware with high radiation fields. The D and D mode selected for the facility was removal of the contaminated hardware and decontamination of several of the storage holes to lower contamination levels. Special shielded disposal containers were constructed to allow removal and transport of the radioactive hardware without exposing personnel to high radiation fields. After removal of the hardware, long-handled mops and brushes were used to decontaminate the storage holes. In addition to describing D and D operations and the final facility condition, project cost and schedule information is reported. 14 figures, 2 tables.

Kaiser, L.L.

1984-01-01

106

The THMIS-MTR observation of a active region filament  

NASA Astrophysics Data System (ADS)

We present some THMIS-MTR observations of a active region filament on September 4, 2002. The full stokes parameters of the filament were obtained in H?, CaII 8542 and FeI 6302. By use of the data with high spatial resolution(0.44" per pixel), we probed the fine structure of the filament and gave out the parameters at the barbs' endpoints, including intensity, velocity and longitudinal magnetic field. Comparing the quiescent filament which we have discussed before, we find that: 1)The velocities of the barbs' endpoints are much bigger in the active region filament, the values are more than one thousand meters per second. 2)The barbs' endpoints terminate at the low logitudinal magnetic field in the active region filament, too.

Zong, W. G.; Tang, Y. H.; Fang, C.

107

Nuclear Accountability Data at the Eurex Reprocessing Plant. Pt. 1. MTR Fuel Reprocessing Campaign.  

National Technical Information Service (NTIS)

In the present work the physical inventory's and fissile material balance's data, which have been collected during the irradiated MTR fuel reprocessing campaign at the EUREX plant in Saluggia (VC), are reported, together with the most important procedures...

S. Ilardi F. Pozzi

1976-01-01

108

ENGINEERING TEST REACTOR, TRA642. CONTEXTUAL VIEW ORIENTATING ETR TO MTR. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ENGINEERING TEST REACTOR, TRA-642. CONTEXTUAL VIEW ORIENTATING ETR TO MTR. CAMERA IS ON ROOF OF MTR BUILDING AND FACES DUE SOUTH. MTR SERVICE BUILDING, TRA-635, IN LOWER RIGHT CORNER. STEEL FRAMES SHOW BUILDINGS TO BE ATTACHED TO ETR BUILDING. HIGH-BAY SECTION IN CENTER IS REACTOR BUILDING. TWO-STORY CONTROL ROOM AND OFFICE BUILDING, TRA-647, IS BETWEEN IT AND MTR SERVICE BUILDING. STRUCTURE TO THE LEFT (WITH NO FRAMING YET) IS COMPRESSOR BUILDING, TRA-643, AND BEYOND IT WILL BE HEAT EXCHANGER BUILDING, TRA-644, GREAT SOUTHERN BUTTE ON HORIZON. INL NEGATIVE NO. 56-2382. Jack L. Anderson, Photographer, 6/10/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

109

A PRML with modified branches of a dual MTR code for high-density PMR channels  

NASA Astrophysics Data System (ADS)

Maximum transition run (MTR, j) code is a modulation code that limits the consecutive transitions. We present a dual MTR code that can be applicable to high-density perpendicular magnetic recording (PMR) channels. The code restricts j=2 in each codeword and allows j=3 when codewords are connected. Furthermore, to improve the detection performance of the PMR systems, we propose a partial response maximum likelihood (PRML) detection scheme with modified branches of the Viterbi trellis for the code. The PRML detection of the dual MTR code achieves an SNR gain of more than 2 and 0.3 dB over the conventional fourth-order PRML detections with rate 8/9 code and rate 6/7 MTR ( j=2) code at 10 -5 bit error rate (BER) in the PMR channel model, respectively.

Lee, Joohyun; Lee, Jaejin

2005-02-01

110

Methionine synthase and thymidylate synthase gene polymorphisms and colorectal adenoma risk: the self defense forces study.  

PubMed

Folate-mediated one-carbon metabolism has been implicated in colorectal carcinogenesis. We investigated associations of functional genetic polymorphisms of methionine synthase (MTR), MTR reductase (MTRR), and thymidylate synthase (TS) with colorectal adenomas. The study subjects were 455 cases of colorectal adenomas and 1052 controls with no polyp at colonoscopy. Genotypes were determined for MTR A2756G, MTRR A66G and two polymorphisms in the TS gene, 28-bp tandem repeat polymorphism in the promoter enhancer region (TSER) and 6-bp deletion polymorphism at position 1494 in the 3' untranslated region (TS 1494del6). We also examined the alcohol-genotype and gene-gene interactions on adenoma risk. The GG genotype of MTR A2756G was associated with an increased risk of colorectal adenomas; odds ratios for AG and GG versus AA genotype were 0.99 (95% confidence interval 0.78-1.26) and 1.72 (1.04-2.82), respectively. The increase in the risk associated with MTR 2756GG genotype was evident in men with high alcohol consumption (?30 mL/d), but not in those with low alcohol consumption (interaction P = 0.03). Men who were homozygous for the TSER double-repeat allele had a slightly decreased risk of colorectal adenomas as compared with those homozygous for the TSER triple-repeat allele. Neither MTRR A66G nor TS 1494del6 was associated with colorectal adenomas. There was no measurable interaction either between MTR A2756G and MTRR A66G or between TSER and TS 1494del6. MTR A2756G appears to be associated with colorectal adenoma risk differently according to alcohol consumption. The MTR-catalyzed reaction may play an important role in the development of colorectal adenomas. PMID:22407825

Yoshimitsu, Shinichiro; Morita, Makiko; Hamachi, Tadamichi; Tabata, Shinji; Abe, Hiroshi; Tajima, Osamu; Uezono, Kousaku; Ohnaka, Keizo; Kono, Suminori

2012-10-01

111

A combinatorial technique for constructing high-rate MTR-RLL codes  

Microsoft Academic Search

We present advanced combinatorial techniques for constructing maximum runlength-limited (RLL) block codes and maximum transition run (MTR) codes. These codes find widespread application in recording systems. The proposed techniques are used to construct a high-rate multipurpose modulation code for recording systems. The code, a rate 16\\/17, (0,3,2,2) MTR code, that also fulfills (0,15,9,9) RLL constraints is a high-rate distance-enhancing code

Adriaan J. van Wijngaarden; Emina Soljanin

2001-01-01

112

Data Detection Performance of an MTR-UWB Receiver in the Presence of Timing Errors  

Microsoft Academic Search

A multiuser transmitted-reference (MTR) ultra wideband (UWB) transceiver is recently proposed to not only increase the data transmission rate, but also enable multiple access effectively. Both features are realized by incorporating frame-rate pseudo-random sequences. This paper further studies detection performance of the MTR receiver when timing is acquired with some random errors from clock synchronization, delay estimation, etc. A timing

Brian M. Sadler; Zhengyuan Xu; Jin Tang

2005-01-01

113

MTR, TRA603. THIRD FLOOR PLAN AND ROOF PLAN. CONTROL ROOM, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, TRA-603. THIRD FLOOR PLAN AND ROOF PLAN. CONTROL ROOM, OFFICES, CONFERENCE ROOM, BATHROOMS. HOOD VENT. BALCONY CONNECTS THIRD FLOOR TO AND SIDES OF MTR. STAIRWAYS TO BALCONY PLATFORMS AROUND REACTOR. CRANE ACCESS CATWALK. BLAW-KNOX 3150-803-4, 7/1950. INL INDEX NO. 531-0603-00-098-100563, REV. 10. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

114

Spontaneous Mutation at the mtr Locus in Neurospora: The Molecular Spectrum in Wild-Type and a Mutator Strain  

Microsoft Academic Search

Sequence analysis of 34 mtr mutations has yielded the first molecular spectrum of spontaneous mutants in Neurospora crassa. The great majority of the mutations are base substitutions (48%) or deletions (35%). In addition, sequence analysis of the entire mtr region, including the 1472-base pair open reading frame and 1205 base pairs of flanking DNA, was performed in both the Oak

Davin Dillon; David Stadler

115

Evidence for grey matter MTR abnormality in minimally disabled patients with early relapsing-remitting multiple sclerosis  

Microsoft Academic Search

Objectives: To establish whether magnetisation transfer ratio (MTR) histograms are sensitive to change in normal appearing grey matter (NAGM) in early relapsing-remitting multiple sclerosis (RRMS) in the absence of significant disability; and to assess whether grey or white matter MTR measures are associated with clinical measures of impairment in early RRMSMethods: 38 patients were studied (mean disease duration 1.9 years

G R Davies; L Ramio?-Torrenta?; A Hadjiprocopis; D T Chard; C M B Griffin; W Rashid; G J Barker; R Kapoor; A J Thompson; D H Miller

2004-01-01

116

Shielding analysis of the NAC-LWT cask with MTR fuel using SCALE  

SciTech Connect

NAC International has used the SCALE Code Package extensively for transport and storage cask design. This includes the design of the NAC-STC dual purpose cask, the ENSA-DPT dual purpose cask as well as design modifications to the NAC-LWT cask. The NAC-LWT is a legal weight truck cask that was originally designed to transport one pressurized water reactor (PWR) fuel assembly or two boiling water reactor (BWR) fuel assemblies. Recently, this cask has been modified to transport up to 42 materials test reactor (MTR) fuel elements. This paper discusses the use of the SCALE package in performing a source term analysis of MTR fuel and shielding analysis of the NAC-LWT cask in support of a 10 CFR Part 71 license amendment for MTR fuel contents.

Napolitano, D.G. [NAC International, Norcross, GA (United States)

1995-12-31

117

Local magnetization transfer ratio signal inhomogeneity is related to subsequent change in MTR in lesions and normal-appearing white-matter of multiple sclerosis patients  

Microsoft Academic Search

Multiple sclerosis (MS) lesions show differing degrees of demyelination and remyelination. Changes in myelin content are associated with changes in magnetization transfer on MRI. Since acute inflammation and demyelination are spatially and temporally inhomogeneous, we hypothesized that local magnetic transfer ratio (MTR) heterogeneity might be predictive of subsequent changes in MTR. To test this hypothesis, we analyzed MTR images obtained

J. T. Chen; D. L. Collins; M. S. Freedman; H. L. Atkins; D. L. Arnold

2005-01-01

118

The crystal structure of Mtr4 reveals a novel arch domain required for rRNA processing  

SciTech Connect

The essential RNA helicase, Mtr4, performs a critical role in RNA processing and degradation as an activator of the nuclear exosome. The molecular basis for this vital function is not understood and detailed analysis is significantly limited by the lack of structural data. In this study, we present the crystal structure of Mtr4. The structure reveals a new arch-like domain that is specific to Mtr4 and Ski2 (the cytosolic homologue of Mtr4). In vivo and in vitro analyses demonstrate that the Mtr4 arch domain is required for proper 5.8S rRNA processing, and suggest that the arch functions independently of canonical helicase activity. In addition, extensive conservation along the face of the putative RNA exit site highlights a potential interface with the exosome. These studies provide a molecular framework for understanding fundamental aspects of helicase function in exosome activation, and more broadly define the molecular architecture of Ski2-like helicases.

Jackson, R.N.; Robinson, H.; Klauer, A. A.; Hintze, B. J.; van Hoof, A.; Johnson, S. J.

2010-07-01

119

MTR,TRA603. EXPERIMENTERS' SPACE ALLOCATIONS IN BASEMENT AS OF 1963. SHIELDED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR,TRA-603. EXPERIMENTERS' SPACE ALLOCATIONS IN BASEMENT AS OF 1963. SHIELDED CUBICLES WERE IDENTIFIED BY SPONSORING LABORATORY AND ITS TEST HOLE NUMBER IN THE REACTOR, IE, "KAPL HB-1" SIGNIFIED KNOLLS ATOMIC POWER LABORATORY, HORIZONTAL BEAM NO. 1. "WAPD" WAS WESTINGHOUSE ATOMIC POWER DIVISION. CATCH TANKS AND SAMPLE STATIONS FOR TEST LOOPS WERE ASSOCIATED WITH THESE CUBICLES. NOTE DESKS, STORAGE CABINETS, SWITCH GEAR, INSTRUMENT PANELS. PHILLIPS PETROLEUM COMPANY MTR-E-5205, 4/1963. INL INDEX NO. 531-0603-00-706-009757, REV. 5. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

120

MTR WING, TRA604, INTERIOR. BASEMENT. INTERIOR VIEW FROM SAME LOCATION ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING, TRA-604, INTERIOR. BASEMENT. INTERIOR VIEW FROM SAME LOCATION IN WEST CORRIDOR AS PHOTO ID-33-G-42 BUT CAMERA FACES SOUTH. SIGN ON DOOR FOR "PIPE TUNNEL" WARNS OF RADIOLOGICAL AND ASBESTOS HAZARDS. DOOR HAS METAL HASPS. SIGN ON OVERHEAD WASTE HEAT RECOVERY PIPES SAYS THEY CONTAIN "ASBESTOS FREE INSULATION." FIRE DOOR AT LEFT LEADS TO STAIRWAY TO FIRST FLOOR. DOOR AT RIGHT LEADS TO ROOM WHICH ONCE CONTAINED MTR LIBRARY. INL NEGATIVE NO. HD46-13-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

121

Electrochemical interrogations of the Mtr cytochromes from Shewanella : opening a potential window  

Microsoft Academic Search

The multi-heme cytochromes from Shewanella oneidensis associated with the dissimilatory metal reduction (DMR) pathway have been investigated using the technique of protein film\\u000a voltammetry (PFV). Using PFV, we have interrogated each of the multi-heme cytochromes (MtrA, STC, and solubilized versions\\u000a of the membrane-bound proteins CymA, OmcA, and MtrC) under identical conditions for the first time. Each cytochrome reveals\\u000a a broad

Mackenzie Firer-Sherwood; Gökçe Su Pulcu; Sean J. Elliott

2008-01-01

122

MTR BUILDING INTERIOR, TRA603. CAMERA IS ON SECOND FLOOR BALCONY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA IS ON SECOND FLOOR BALCONY LOOKING DOWN ON REACTOR FLOOR, FACING NORTHEAST, THE WEST AND SOUTH FACES OF THE REACTOR. MOCK-UP APPARATUS IS AT RIGHT OF VIEW. INL NEGATIVE NO. HD-46-3-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

123

SOUTH WING, MTR661. INTERIOR DETAIL INSIDE LAB ROOM 127. CAMERA ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTH WING, MTR-661. INTERIOR DETAIL INSIDE LAB ROOM 127. CAMERA FACES WEST, LOOKING DIRECTLY AT A PAIR OF HOT CELLS, THEIR WINDOWS, AND MASTER/SLAVE MANIPULATORS. CABINET AT LEFT IS ABOVE GLOVE BOX. INL NEGATIVE NO. HD46-8-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

124

MTR STACK, TRA710, CONTEXTUAL VIEW, CAMERA FACING SOUTH. PERIMETER SECURITY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR STACK, TRA-710, CONTEXTUAL VIEW, CAMERA FACING SOUTH. PERIMETER SECURITY FENCE AND SECURITY LIGHTING IN VIEW AT LEFT. INL NEGATIVE NO. HD52-1-1. Mike Crane, Photographer, 5/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

125

MTR BUILDING, TRA603. SOUTH ELEVATION. PRECAST INSULATED PANEL DETAILS. AIR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, TRA-603. SOUTH ELEVATION. PRECAST INSULATED PANEL DETAILS. AIR DUCT PLENUM CHAMBER. BLAW-KNOX 3150-80-5, 9/1950. INL INDEX NO. 531-0603-00-098-100564, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

126

MTR WING, TRA604. PRECAST CONCRETE PANELS AND DIMENSIONS FOR PANELS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING, TRA-604. PRECAST CONCRETE PANELS AND DIMENSIONS FOR PANELS K THROUGH Q. BLAW-KNOX 3150-804-21, SHEET #2, 11/1950. INL INDEX NO. 531-0604-62-098-100645, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

127

MTR WING, TRA604. DETAILS OF LABORATORIES ALONG SOUTH WALL: TABLES, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING, TRA-604. DETAILS OF LABORATORIES ALONG SOUTH WALL: TABLES, FUME HOODS, DESKS. BLAW-KNOX 3150-404-4, 7/1950. INL INDEX NO. 531-0604-00-098-100084, REV. 8. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

128

SOUTH WING, MTR661. INTERIOR DETAIL INSIDE LAB ROOM 131. CAMERA ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTH WING, MTR-661. INTERIOR DETAIL INSIDE LAB ROOM 131. CAMERA FACING NORTHEAST. NOTE CONCRETE BLOCK WALLS. SAFETY SHOWER AND EYE WASHER AT REAR WALL. INL NEGATIVE NO. HD46-7-2. Mike Crane, Photographer, 2/2005. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

129

MTR BUILDING INTERIOR, TRA603. BASEMENT. CAMERA IS IN SOUTHWEST QUADRANT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. BASEMENT. CAMERA IS IN SOUTHWEST QUADRANT OF BASEMENT AND FACING NORTHEAST. PANEL DISPLAYS DATA READOUTS. INL NEGATIVE NO. HD46-6-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

130

MTR STACK, TRA71, DETAIL OF PUMICE BLOCK SERVICE BUILDING AT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR STACK, TRA-71-, DETAIL OF PUMICE BLOCK SERVICE BUILDING AT BASE OF STACK. CAMERA FACING SOUTHEAST. INL NEGATIVE NO. HD52-1-2. Mike Crane, Photographer, 5/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

131

MTR WING A, TRA604, INTERIOR. MAIN FLOOR. VIEW DOWN CORRIDOR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. MAIN FLOOR. VIEW DOWN CORRIDOR 2 (BETWEEN ROOMS ON WEST WALL AND IN CENTER OF FLOOR). CAMERA FACING SOUTH. PUMICE BLOCK WALLS. INL NEGATIVE NO. HD46-12-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

132

MTR, TRA603. CONTROL ROOM DETAILS. ACOUSTIC PLASTER CEILING, USHAPED CONSOLE, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, TRA-603. CONTROL ROOM DETAILS. ACOUSTIC PLASTER CEILING, U-SHAPED CONSOLE, INSTRUMENT PANELS, GLASS DOOR, ASPHALT TILE FLOOR AND COLORS. BLAW-KNOX 3150-803-11, 10/1950. INL INDEX NO. 531-0603-00-098-100570, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

133

MTR BUILDING INTERIOR, TRA603, REACTOR FLOOR. VIEW DOWN CORRIDOR CREATED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, REACTOR FLOOR. VIEW DOWN CORRIDOR CREATED BY EAST WALL ON LEFT AND APPARATUS ON RIGHT. CAMERA FACING SOUTH. INL NEGATIVE NO. HD46-1-3. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

134

MTR BUILDING INTERIOR, TRA603, BASEMENT. CAMERA IS IN OFFICE AREA ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, BASEMENT. CAMERA IS IN OFFICE AREA A-101 AND FACING EAST. INL NEGATIVE NO. HD46-6-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

135

MTR BUILDING, INTERIOR, TRA603. BASEMENT. CAMERA IS IN NORTHWEST CORNER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, INTERIOR, TRA-603. BASEMENT. CAMERA IS IN NORTHWEST CORNER FACING SOUTHEAST. AREA IS IN USE FOR FILE STORAGE. INL NEGATIVE NO. HD46-6-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

136

MTR BUILDING INTERIOR, TRA603. DETAIL OF OFFICE (ROOM 306) ON ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. DETAIL OF OFFICE (ROOM 306) ON THIRD FLOOR BALCONY. CAMERA FACING WEST. INL NEGATIVE NO. HD46-5-3. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

137

REACTOR SERVICES BUILDING, TRA635. EAST SIDE. CAMERA LOOKING NORTHWEST. MTR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

REACTOR SERVICES BUILDING, TRA-635. EAST SIDE. CAMERA LOOKING NORTHWEST. MTR BUILDING, TRA-603, AT RIGHT OF VIEW. INL NEGATIVE NO. HD46-41-2. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

138

MTR BUILDING INTERIOR, TRA603, REACTOR FLOOR. DETAIL OF REACTOR TEST ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, REACTOR FLOOR. DETAIL OF REACTOR TEST HOLE OPENING IN WEST FACE. CAMERA FACING NORTHEAST. INL NEGATIVE NO. HD46-2-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

139

MTR WING A, TRA604, INTERIOR. SECOND FLOOR, GENERAL VIEW OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. SECOND FLOOR, GENERAL VIEW OF OFFICES 210 AND 209 AS SEEN FROM TOP OF STAIRWAY. CAMERA FACES SOUTH. INL NEGATIVE NO. HD46-9-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

140

MTR BUILDING INTERIOR, TRA603, REACTOR FLOOR. CONTEXTUAL VIEW OF SOUTHWEST ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, REACTOR FLOOR. CONTEXTUAL VIEW OF SOUTHWEST CORNER OF REACTOR. WEST FACE IS TOWARD LEFT OF VIEW. CAMERA FACING NORTHEAST. INL NEGATIVE NO. HD46-2-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

141

MTR BUILDING INTERIOR, TRA603. CAMERA FACING SOUTHEAST CORNER OF REACTOR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA FACING SOUTHEAST CORNER OF REACTOR FLOOR. SUPPLIES AND EQUIPMENT RELATE TO MOCK-UP PROJECT. NOTE PRECAST WALL PANELS SUPPORTED BY VERTICAL COLUMNS OF REINFORCED CONCRETE. INL NEGATIVE NO. HD46-4-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

142

SOUTH WING, TRA661. WEST SIDE. CAMERA FACING NORTHEAST. MTR WEST ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTH WING, TRA-661. WEST SIDE. CAMERA FACING NORTHEAST. MTR WEST WALL BEYOND ROOF LINE. INL NEGATIVE NO. HD46-45-1. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

143

Search for polarimetric sensitivity in the first observations with THEMIS spectropolarimetric mode MTR (August 1998 campaign)  

Microsoft Academic Search

The present paper is devoted to the search for the polarimetric sensitivity level in observations of the Fe I 5576 Å line performed with the THEMIS spectropolarimetric mode MTR on August 23 1998. This line is insensitive to the Zeeman effect and the present work is thus useful to calibration purposes. The upper level of the line is unpolarizable (J=0)

V. Bommier; J. Rayrole

2002-01-01

144

MTR BUILDING INTERIOR, TRA603. CAMERA IS AT NORTH END OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT NORTH END OF THIRD FLOOR BALCONY LOOKING SOUTHEAST. DETAIL OF REACTOR'S NORTH FACE AND ITS TEST HOLES. MOCK-UP APPARATUS IS BEYOND REACTOR. INL NEGATIVE NO. HD46-5-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

145

MTR WING A, TRA604, INTERIOR. MAIN FLOOR, DETAIL OF LABORATORY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. MAIN FLOOR, DETAIL OF LABORATORY 123. CAMERA LOOKING NORTHEAST. INL NEGATIVE NO. HD46-12-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

146

MTR BUILDING INTERIOR, TRA603. CAMERA IS AT SOUTH END OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT SOUTH END OF THIRD FLOOR BALCONY LOOKING NORTHEAST. BRIDGE BETWEEN BALCONY AND REACTOR TOP AT LEFT OF VIEW. INL NEGATIVE NO. HD46-5-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

147

MTR WING A, TRA604, INTERIOR, MAIN FLOOR. DETAIL VIEW OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR, MAIN FLOOR. DETAIL VIEW OF MACHINE SHOP AT SOUTHWEST CORNER OF WING. CAMERA FACING WEST TOWARDS WINDOW IN WEST WALL. INL NEGATIVE NO. HD46-31-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

148

MTR WING A, TRA604, INTERIOR. BASEMENT. CAMERA FACES WEST, ITS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. BASEMENT. CAMERA FACES WEST, ITS BACK TO A FREIGHT ELEVATOR. ELECTRIC PANELS AT LEFT OF VIEW. INL NEGATIVE NO. HD46-13-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

149

MTR WING A, TRA604. SOUTH SIDE. CAMERA FACING NORTH. THIS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604. SOUTH SIDE. CAMERA FACING NORTH. THIS VIEW TYPIFIES TENDENCY FOR EXPANSIONS TO TAKE THE FORM OF PROJECTIONS AND INFILL USING AVAILABLE YARD SPACES. INL NEGATIVE NO. HD47-44-3. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

150

MTR BUILDING INTERIOR, TRA603. CAMERA IS ON SECOND FLOOR BALCONY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA IS ON SECOND FLOOR BALCONY LOOKING DOWN ON WEST FACE OF REACTOR. SHIELDING BLOCKS IN FOREGROUND ATOP CABINET. INL NEGATIVE NO. HD46-3-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

151

MTR STACK, TRA710, DETAIL OF BASE. CAMERA FACING NORTH. SIGN ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR STACK, TRA-710, DETAIL OF BASE. CAMERA FACING NORTH. SIGN SAYS "DANGER, DO NOT USE THIS LADDER." TRA-605, PROCESS WATER BUILDING, IN VIEW AT LEFT. INL NEGATIVE NO. HD52-1-3. Mike Crane, Photographer, 5/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

152

SOUTH WING, MTR661. INTERIOR DETAIL INSIDE LAB ROOM 120, USED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTH WING, MTR-661. INTERIOR DETAIL INSIDE LAB ROOM 120, USED RECENTLY AS STORAGE AREA. CAMERA FACING NORTHWEST. INL NEGATIVE NO. HD46-8-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

153

MTR WING A, TRA604, INTERIOR. MAIN FLOOR. DETAILS OF MACHINE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. MAIN FLOOR. DETAILS OF MACHINE SHOP. CAMERA FACING SOUTH. INL NEGATIVE NO. HD46-31-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

154

REACTOR SERVICES BUILDING, TRA635. WEST SIDE. CAMERA LOOKING NORTHEAST. MTR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

REACTOR SERVICES BUILDING, TRA-635. WEST SIDE. CAMERA LOOKING NORTHEAST. MTR (TRA-603) AT LEFT OF VIEW. INL NEGATIVE NO. HD46-41-2. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

155

SOUTH WING, TRA661. SOUTH SIDE. CAMERA FACING NORTH. MTR HIGH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTH WING, TRA-661. SOUTH SIDE. CAMERA FACING NORTH. MTR HIGH BAY BEYOND. INL NEGATIVE NO. HD46-45-3. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

156

MTR WING A, TRA604, INTERIOR. MAIN FLOOR. DETAIL VIEW INSIDE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. MAIN FLOOR. DETAIL VIEW INSIDE LABORATORY 110. CAMERA FACING SOUTH. INL NEGATIVE NO. HD46-12-3. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

157

MTR BUILDING INTERIOR, TRA603, REACTOR FLOOR. DETAIL OF REACTOR'S SOUTH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, REACTOR FLOOR. DETAIL OF REACTOR'S SOUTH FACE. CAMERA FACING NORTHWESTERLY. INL NEGATIVE NO. HD46-1-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

158

Solution of the neutron spectrum adjustment problem in a typical MTR type research reactor  

Microsoft Academic Search

The work presented in this paper discusses the solution of the neutron energy spectrum adjustment problem in the Pakistan Research Reactor-1 (PARR-1), which is a typical Material Test Reactor (MTR) fuelled with low enriched uranium. This article examines how the different adjustment codes such as SANDBP, MSANDB, MSITER and MIEKEB do modification to the input spectrum and how this in

S. R. Malkawi; N. Ahmad

2001-01-01

159

MTR, TRA603. FOUNDATION PLAN, SECTION A ALONG NORTH/SOUTH AXIS SHOWS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, TRA-603. FOUNDATION PLAN, SECTION A ALONG NORTH/SOUTH AXIS SHOWS PIPE TUNNEL FOR COOLANT WATER. BLAW-KNOX 3150-803-33, 5/1950. INL INDEX NO. 531-0603-62-098-100589, REV. 8. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

160

MTR, TRA603. SUBBASEMENT FLOOR PLAN. INLET/OUTLET TUNNELS FOR COOLANT WATER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, TRA-603. SUB-BASEMENT FLOOR PLAN. INLET/OUTLET TUNNELS FOR COOLANT WATER (NORTH SIDE) AND AIR (SOUTH SIDE). RABBIT CANAL AND BULKHEADS. SUMPS AND DRAINS. BLAW-KNOX 3150-3-7, 3/1950. INL INDEX NO. 531-0603-00-098-100006, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

161

MTR, TRA603. FOUNDATION PLAN, SECTION C THROUGH COOLANT WATER EXIT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR, TRA-603. FOUNDATION PLAN, SECTION C THROUGH COOLANT WATER EXIT TUNNEL ALONG NORTH SIDE AS IT RETURNS TO MAIN COOLANT TUNNEL LEAVING BUILDING TO THE NORTH. BLAW-KNOX 3150-803-35, 5/1950. INL INDEX NO. 531-0603-62-098-100591, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

162

MTR BLOWER AND FAN HOUSE, TRA610. FIRST FLOOR, ROOF AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BLOWER AND FAN HOUSE, TRA-610. FIRST FLOOR, ROOF AND FOUNDATION PLANS. DOOR SCHEDULE AND LOCATION OF STRUCTURAL STEEL AND HOLLOW METAL DOORS. BLAW-KNOX 3150-810-1, 1/1951. INL INDEX NO. 531-0610-00-098-100688, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

163

MTR WING A, TRA604, INTERIOR. MAIN FLOOR. DETAIL VIEW INSIDE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING A, TRA-604, INTERIOR. MAIN FLOOR. DETAIL VIEW INSIDE LABORATORY 114. CAMERA FACING NORTH. DISPOSAL OF RADIOACTIVE MATERIALS IS UNDERWAY. INL NEGATIVE NO. HD46-12-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

164

Towards Electrosynthesis in Shewanella: Energetics of Reversing the Mtr Pathway for Reductive Metabolism  

PubMed Central

Bioelectrochemical systems rely on microorganisms to link complex oxidation/reduction reactions to electrodes. For example, in Shewanella oneidensis strain MR-1, an electron transfer conduit consisting of cytochromes and structural proteins, known as the Mtr respiratory pathway, catalyzes electron flow from cytoplasmic oxidative reactions to electrodes. Reversing this electron flow to drive microbial reductive metabolism offers a possible route for electrosynthesis of high value fuels and chemicals. We examined electron flow from electrodes into Shewanella to determine the feasibility of this process, the molecular components of reductive electron flow, and what driving forces were required. Addition of fumarate to a film of S. oneidensis adhering to a graphite electrode poised at ?0.36 V versus standard hydrogen electrode (SHE) immediately led to electron uptake, while a mutant lacking the periplasmic fumarate reductase FccA was unable to utilize electrodes for fumarate reduction. Deletion of the gene encoding the outer membrane cytochrome-anchoring protein MtrB eliminated 88% of fumarate reduction. A mutant lacking the periplasmic cytochrome MtrA demonstrated more severe defects. Surprisingly, disruption of menC, which prevents menaquinone biosynthesis, eliminated 85% of electron flux. Deletion of the gene encoding the quinone-linked cytochrome CymA had a similar negative effect, which showed that electrons primarily flowed from outer membrane cytochromes into the quinone pool, and back to periplasmic FccA. Soluble redox mediators only partially restored electron transfer in mutants, suggesting that soluble shuttles could not replace periplasmic protein-protein interactions. This work demonstrates that the Mtr pathway can power reductive reactions, shows this conduit is functionally reversible, and provides new evidence for distinct CymA:MtrA and CymA:FccA respiratory units.

Ross, Daniel E.; Flynn, Jeffrey M.; Baron, Daniel B.; Gralnick, Jeffrey A.; Bond, Daniel R.

2011-01-01

165

Human cytomegalovirus mtrII oncoprotein binds to p53 and down-regulates p53-activated transcription.  

PubMed Central

The 79-amino-acid (79-aa) open reading frame (UL111a) gene within morphological transforming region II (mtrII) of human cytomegalovirus strain Towne has been shown to transform rodent cells in vitro (J. Thompson, J. Doniger, and L. J. Rosenthal, Arch. Virol. 136:161-172, 1994). Moreover, a translation termination linker (TTL) mutant of mtrII that coded for the first 49 aa of mtrII oncoprotein (designated TTL49) was sufficient for malignant transformation, whereas a TTL mutant that coded for the first 24 aa (designated TTL24) was not. The current study demonstrates the binding of mtrII oncoprotein to the tumor suppressor protein p53 both in vivo using transiently transfected cells and in vitro using labeled proteins. Furthermore, the C-terminally truncated mtrII protein TTL49, but not truncated protein TTL24, bound to p53. The mtrII binding domain mapped to the N-terminal region of p53, residues 1 to 106, with a critical region from aa 27 to 44, whereas the p53 binding domain of mtrII protein was the first 49 aa. Furthermore, mtrII inhibited p53-activated transcription, indicating its ability to alter p53-directed cellular regulatory mechanisms. mtrII oncoprotein was detected both in stably transfected NIH 3T3 cell lines and human cytomegalovirus-infected HEL 299 cells (as early as 12 h after infection) in the perinuclear region and in the nucleus. mtrII-transformed cell lines, at both early and late passage, exhibited high levels of p53 with a 15-fold-extended half-life. However, p53-activated transcription was suppressed in these cells in spite of the increased p53 levels. Finally, the results with wild-type mtrII and its TTL mutants with respect to p53 binding, p53-activated transcription, and transforming ability suggest that the mechanism of mtrII transformation is linked to both p53 binding and disruption of p53 cell regulation.

Muralidhar, S; Doniger, J; Mendelson, E; Araujo, J C; Kashanchi, F; Azumi, N; Brady, J N; Rosenthal, L J

1996-01-01

166

Extracellular Reduction of Hexavalent Chromium by Cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 ?  

PubMed Central

To characterize the roles of cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 in Cr(VI) reduction, the effects of deleting the mtrC and/or omcA gene on Cr(VI) reduction and the cellular locations of reduced Cr(III) precipitates were investigated. Compared to the rate of reduction of Cr(VI) by the wild type (wt), the deletion of mtrC decreased the initial rate of Cr(VI) reduction by 43.5%, while the deletion of omcA or both mtrC and omcA lowered the rate by 53.4% and 68.9%, respectively. In wt cells, Cr(III) precipitates were detected by transmission electron microscopy in the extracellular matrix between the cells, in association with the outer membrane, and inside the cytoplasm. No extracellular matrix-associated Cr(III) precipitates, however, were found in the cytochrome mutant cell suspension. In mutant cells without either MtrC or OmcA, most Cr(III) precipitates were found in association with the outer membrane, while in mutant cells lacking both MtrC and OmcA, most Cr(III) precipitates were found inside the cytoplasm. Cr(III) precipitates were also detected by scanning election microscopy on the surfaces of the wt and mutants without MtrC or OmcA but not on the mutant cells lacking both MtrC and OmcA, demonstrating that the deletion of mtrC and omcA diminishes the extracellular formation of Cr(III) precipitates. Furthermore, purified MtrC and OmcA reduced Cr(VI) with apparent kcat values of 1.2 ± 0.2 (mean ± standard deviation) and 10.2 ± 1 s?1 and Km values of 34.1 ± 4.5 and 41.3 ± 7.9 ?M, respectively. Together, these results consistently demonstrate that MtrC and OmcA are the terminal reductases used by S. oneidensis MR-1 for extracellular Cr(VI) reduction where OmcA is a predominant Cr(VI) reductase.

Belchik, Sara M.; Kennedy, David W.; Dohnalkova, Alice C.; Wang, Yuanmin; Sevinc, Papatya C.; Wu, Hong; Lin, Yuehe; Lu, H. Peter; Fredrickson, James K.; Shi, Liang

2011-01-01

167

Increased prevalence of combined MTR and MTHFR genotypes among individuals with severely elevated total homocysteine plasma levels  

Microsoft Academic Search

The prevalence of the methionine synthase (MTR) 2756A?G polymorphism among individuals with severely elevated total homocysteine (tHcy) plasma levels is unknown. Therefore, 1,716 subjects, including 415 hemodialysis patients, 179 peritoneal dialysis patients, 733 kidney graft recipients, and 389 healthy subjects, were investigated. The distribution of MTR 2756A?G, as well as 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C?T\\/1298A?C, genotypes among study participants with extremely

Alexandra Feix; Robert Fritsche-Polanz; Josef Kletzmayr; Andreas Vychytil; Walter H. Hörl; Gere Sunder-Plassmann; Manuela Födinger

2001-01-01

168

Experimental performance comparison of FDTS\\/DF detectors: 8\\/9 (0,k) vs. 4\\/5 MTR codes  

Microsoft Academic Search

The performance of an FDTS\\/DF detector is compared using two different RLL coding techniques. The new Maximum Transition Run (MTR) codes have been proposed for use with FDTS\\/DF detectors because of demonstrated coding gains. This work compares the performance of an 8\\/9 (0,4\\/4) code to a 4\\/5 MTR code using actual MR head signals captured from a spinstand. The coding

Zachary A. Keirn; S. G. McCarthy

1997-01-01

169

[ 123 I]Mtr-TOCA, a radioiodinated and carbohydrated analogue of octreotide: scintigraphic comparison with [ 111 In]octreotide  

Microsoft Academic Search

Purpose: Scintigraphy with maltotriose-( 123 I) Tyr 3 -octreotate (( 123 I)Mtr-TOCA) is compared with ( 111 In) DTPA-Phe 1 -octreotide (( 111 In)OC) to assess the differ- ences in pharmacokinetics and imaging properties as well as to estimate the therapeutic potential of the correspond- ing ( 131 I)Mtr-TOCA. Methods: Six patients with somatostatin receptor (sstr)- positive tumours were assessed

Alexander Stahl; Günther Meisetschläger; Margret Schottelius; Kjerstin Bruus-Jensen; Ingo Wolf; Klemens Scheidhauer; Markus Schwaiger

2006-01-01

170

An Assessment of the MTR Aquatic Plant Bioindication System for Determining the Trophic Status of Polish Rivers  

Microsoft Academic Search

Mean Trophic Rank (MTR), a new British biological macrophyte-based method for assessing trophic status of rivers was applied in Poland in 2000-2001. The occurrence and abundance of 86 aquatic plant species was recorded at 48 sites on 19 rivers in the lowland part of Poland. Forty-six of these species are MTR scoring taxa used in the British system, but another

K. Szoszkiewicz; K. Karolewicz; A. ?awniczak; F. H. Dawson

2002-01-01

171

Crystal Structure of the Neisseria gonorrhoeae MtrD Inner Membrane Multidrug Efflux Pump.  

PubMed

Neisseria gonorrhoeae is an obligate human pathogen and the causative agent of the sexually-transmitted disease gonorrhea. The control of this disease has been compromised by the increasing proportion of infections due to antibiotic-resistant strains, which are growing at an alarming rate. The MtrCDE tripartite multidrug efflux pump, belonging to the hydrophobic and amphiphilic efflux resistance-nodulation-cell division (HAE-RND) family, spans both the inner and outer membranes of N. gonorrhoeae and confers resistance to a variety of antibiotics and toxic compounds. We here report the crystal structure of the inner membrane MtrD multidrug efflux pump, which reveals a novel structural feature that is not found in other RND efflux pumps. PMID:24901477

Bolla, Jani Reddy; Su, Chih-Chia; Do, Sylvia V; Radhakrishnan, Abhijith; Kumar, Nitin; Long, Feng; Chou, Tsung-Han; Delmar, Jared A; Lei, Hsiang-Ting; Rajashankar, Kanagalaghatta R; Shafer, William M; Yu, Edward W

2014-01-01

172

Crystal Structure of the Neisseria gonorrhoeae MtrD Inner Membrane Multidrug Efflux Pump  

PubMed Central

Neisseria gonorrhoeae is an obligate human pathogen and the causative agent of the sexually-transmitted disease gonorrhea. The control of this disease has been compromised by the increasing proportion of infections due to antibiotic-resistant strains, which are growing at an alarming rate. The MtrCDE tripartite multidrug efflux pump, belonging to the hydrophobic and amphiphilic efflux resistance-nodulation-cell division (HAE-RND) family, spans both the inner and outer membranes of N. gonorrhoeae and confers resistance to a variety of antibiotics and toxic compounds. We here report the crystal structure of the inner membrane MtrD multidrug efflux pump, which reveals a novel structural feature that is not found in other RND efflux pumps.

Radhakrishnan, Abhijith; Kumar, Nitin; Long, Feng; Chou, Tsung-Han; Delmar, Jared A.; Lei, Hsiang-Ting; Rajashankar, Kanagalaghatta R.; Shafer, William M.; Yu, Edward W.

2014-01-01

173

MTR BUILDING INTERIOR, TRA603. CAMERA IS AT NORTH END OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT NORTH END OF SECOND FLOOR BALCONY LOOKING TOWARDS WORK PLATFORMS ON NORTH FACE OF REACTOR. BRIDGE TO THIRD FLOOR BALCONY FROM TOP OF REACTOR IS AT UPPER RIGHT OF VIEW. CAMERA FACING EASTERLY. INL NEGATIVE NO. HD-46-4-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

174

MTR WING, TRA604. PRECAST CONCRETE PANELS AND DIMENSIONS. TYPES A, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING, TRA-604. PRECAST CONCRETE PANELS AND DIMENSIONS. TYPES A, B, C, D, E, AND F; AND HOW THEY ARE CONNECTED. TYPES C AND D ARE ON WEST SIDE WHERE GLASS BLOCKS SURROUND ENTRY DOOR. BLAW-KNOX 3150-804-20, SHEET #1, 11/1950. INL INDEX NO. 531-0604-62-098-100644, REV. 0. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

175

CFD simulation of the IAEA 10 MW generic MTR reactor under loss of flow transient  

Microsoft Academic Search

Three-dimensional simulation of the IAEA 10MW generic reactor under loss of flow transient is introduced using the CFD code, Fluent. The IAEA reactor calculation is a safety-related benchmark problem for an idealized material testing reactor (MTR) pool type specified in order to compare calculational methods used in various research centers. The flow transients considered include fast loss of flow accidents

Amgad Salama; Salah El-Din El-Morshedy

2011-01-01

176

MTR BUILDING, TRA603. EAST SIDE. CAMERA FACING WEST. CORRUGATED IRON ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, TRA-603. EAST SIDE. CAMERA FACING WEST. CORRUGATED IRON BUILDING MARKED WITH "X" IS TRA-651. TRA-626, TO ITS RIGHT, HOUSED COMPRESSOR EQUIPMENT FOR THE AIRCRAFT NUCLEAR PROPULSION PROGRAM. LATER, IT WAS USED FOR STORAGE. INL NEGATIVE NO. HD46-42-4. Mike Crane, Photographer, April 2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

177

MTR BUILDING, TRA603. SOUTHEAST CORNER, EAST SIDE FACING TOWARD RIGHT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING, TRA-603. SOUTHEAST CORNER, EAST SIDE FACING TOWARD RIGHT OF VIEW. CAMERA FACING NORTHWEST. LIGHT-COLORED PROJECTION AT LEFT IS ENGINEERING SERVICES BUILDING, TRA-635. SMALL CONCRETE BLOCK BUILDING AT CENTER OF VIEW IS FAST CHOPPER DETECTOR HOUSE, TRA-665. INL NEGATIVE NO. HD46-43-3. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

178

MTR BUILDING INTERIOR, TRA603, REACTOR FLOOR. CAMERA IS IN NORTHEAST ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, REACTOR FLOOR. CAMERA IS IN NORTHEAST CORNER FACING SOUTHWEST. NORTH FACE OF REACTOR IS IN LEFT HALF OF VIEW. WEST WALL CONTAINS CONTROL BALCONIES. BRIDGE FROM REACTOR TO SECOND-FLOOR BALCONY IS IN CENTER OF VIEW. INL NEGATIVE NO. HD46-1-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

179

MTR BUILDING INTERIOR, TRA603. CAMERA IS AT NORTH END OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT NORTH END OF THIRD FLOOR BALCONY LOOKING SOUTHEAST AND ACROSS TOP OF REACTOR. MOCK-UP APPARATUS IS BEYOND REACTOR. BRIDGE CONNECTING BALCONY AND REACTOR TOP AT RIGHT OF VIEW. INL NEGATIVE NO. HD46-5-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

180

MTR BUILDING INTERIOR, TRA603, SECOND FLOOR BALCONY. CAMERA FACING NORTH. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, SECOND FLOOR BALCONY. CAMERA FACING NORTH. ROOMS 204, 203, 202, AND 201 ARE TO LEFT. VIEW TOWARDS REACTOR FLOOR IS SEEN THROUGH BALCONY RAILING. PLATFORM BETWEEN REACTOR AND THIRD FLOOR BALCONY IS SEEN BEYOND SQUARE PILLAR IN FOREGROUND. INL NEGATIVE NO. HD46-3-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

181

High transition velocities for solid armatures in the 10-mm MTR railgun  

Microsoft Academic Search

The transitioning of a solid armature on the Materials Test Railgun (MTR) was studied, and data on high-velocity transitions were analyzed. The railgun has a 10-mm square bore, is 0.6-m long, and is designed with a bolted construction for experimental flexibility. Solid 7075-series Al alloy armatures were accelerated to 1.75 km\\/s, and transition was observed at approximately 1.3 km\\/s. These

N. Colon; L. Tran; K. Luu; L. Paul; D. I. Chang; D. A. Sink

1993-01-01

182

Some THEMIS-MTR observations of the second solar spectrum (2000 campaign)  

Microsoft Academic Search

We report spectropolarimetric observations with the THEMIS telescope multi-lines operating mode (MTR) during the 2000 observational period from August 27th to September 1st. We measured the resonance polarization at the limb of a series of lines: Sr I 460.7 nm, Na I D1 589.6 nm and D2 589.0 nm, Ba Ii D1 493.4 nm and D2 455.4 nm, C I

V. Bommier; G. Molodij

2002-01-01

183

MTR BUILDING INTERIOR, TRA603, REACTOR FLOOR. VIEW DOWN CORRIDOR CREATED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BUILDING INTERIOR, TRA-603, REACTOR FLOOR. VIEW DOWN CORRIDOR CREATED BY REACTOR (LEFT OF VIEW) AND WEST WALL ON RIGHT. BRIDGE OVERHEAD PROVIDED ACCESS TO TOP OF REACTOR FROM BALCONY. NOTE WIDTH OF BRIDGE. CAMERA FACING SOUTH TOWARDS OPEN DOOR OF REACTOR SERVICE BUILDING, TRA-635. INL NEGATIVE NO. HD46-1-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

184

Thermodynamics of Electron Flow in the Bacterial Deca-heme Cytochrome MtrF  

SciTech Connect

Electron transporting multiheme cytochromes are essential to the metabolism of microbes that inhabit soils and carry out important biogeochemical processes. Recently the first crystal structure of a prototype bacterial deca-heme cytochrome (MtrF) has been resolved and its electrochemistry characterized. However, the molecular details of electron conductance along heme chains in the cytochrome are difficult to access via experiment due to the nearly identical chemical nature of the heme cofactors. Here we employ large-scale molecular dynamics simulations to compute the reduction potentials of the ten hemes of MtrF in aqueous solution. We find that as a whole they fall within a range of about 0.3 V in agreement with experiment. Individual reduction potentials give rise to a free energy profile for electron conduction that is approximately symmetric with respect to the center of the protein. Our calculations indicate that there is no significant potential bias along the orthogonal octa- and tetra-heme chains suggesting that under aqueous conditions MtrF is a nearly reversible two-dimensional conductor.

Breuer, Marian; Zarzycki, Piotr P.; Blumberger, Jochen; Rosso, Kevin M.

2012-07-01

185

A novel approach with "skeletonised MTR" measures tract-specific microstructural changes in early primary-progressive MS.  

PubMed

We combined tract-based spatial statistics (TBSS) and magnetization transfer (MT) imaging to assess white matter (WM) tract-specific short-term changes in early primary-progressive multiple sclerosis (PPMS) and their relationships with clinical progression. Twenty-one PPMS patients within 5 years from onset underwent MT and diffusion tensor imaging (DTI) at baseline and after 12 months. Patients' disability was assessed. DTI data were processed to compute fractional anisotropy (FA) and to generate a common WM "skeleton," which represents the tracts that are "common" to all subjects using TBSS. The MT ratio (MTR) was computed from MT data and co-registered with the DTI. The skeletonization procedure derived for FA was applied to each subject's MTR image to obtain a "skeletonised" MTR map for every subject. Permutation tests were used to assess (i) changes in FA, principal diffusivities, and MTR over the follow-up, and (ii) associations between changes in imaging parameters and changes in disability. Patients showed significant decreases in MTR over one year in the corpus callosum (CC), bilateral corticospinal tract (CST), thalamic radiations, and superior and inferior longitudinal fasciculi. These changes were located both within lesions and the normal-appearing WM. No significant longitudinal change in skeletonised FA was found, but radial diffusivity (RD) significantly increased in several regions, including the CST bilaterally and the right inferior longitudinal fasciculus. MTR decreases, RD increases, and axial diffusivity decreases in the CC and CST correlated with a deterioration in the upper limb function. We detected tract-specific multimodal imaging changes that reflect the accrual of microstructural damage and possibly contribute to clinical impairment in PPMS. We propose a novel methodology that can be extended to other diseases to map cross-subject and tract-specific changes in MTR. PMID:23616276

Bodini, Benedetta; Cercignani, Mara; Toosy, Ahmed; De Stefano, Nicola; Miller, David H; Thompson, Alan J; Ciccarelli, Olga

2014-02-01

186

Targeted Protein Degradation of Outer Membrane Decaheme Cytochrome MtrC Metal Reductase in Shewanella oneidensis MR-1 Measured Using Biarsenical Probe CrAsH-EDT2  

SciTech Connect

Development of efficient microbial biofuel cells requires an ability to exploit interfacial electron transfer reactions to external electron acceptors, such as metal oxides; such reactions occur in the facultative anaerobic gram-negative bacterium Shewanella oneidensis MR-1 through the catalytic activity of the outer membrane decaheme c-type cytochrome MtrC. Central to the utility of this pathway to synthetic biology is an understanding of cellular mechanisms that maintain optimal MtrC function, cellular localization, and renewal by degradation and resynthesis. In order to monitor trafficking to the outer membrane, and the environmental sensitivity of MtrC, we have engineered a tetracysteine tag (i.e., CCPGCC) at its C-terminus that permits labeling by the cell impermeable biarsenical fluorophore, carboxy-FlAsH (CrAsH) of MtrC at the surface of living Shewanella oneidensis MR-1 cells. In comparison, the cell permeable reagent FlAsH permits labeling of the entire population of MtrC, including proteolytic fragments resulting from incorrect maturation. We demonstrate specific labeling by CrAsH of engineered MtrC which is dependent on the presence of a functional type-2 secretion system (T2S), as evidenced by T2S system gspD or gspG deletion mutants which are incapable of CrAsH labeling. Under these latter conditions, MtrC undergoes proteolytic degradation to form a large 35-38 kDa fragment; this degradation product is also resolved during normal turnover of the CrAsH-labeled MtrC protein. No MtrC protein is released into the medium during turnover, suggesting the presence of cellular turnover systems involving MtrC reuptake and degradation. The mature MtrC localized on the outer membrane is a long-lived protein, with a turnover rate of 0.043 hr-1 that is insensitive to O2 concentration. Maturation of MtrC is relatively inefficient, with substantial rates of turnover of the immature protein prior to export to the outer membrane (i.e., 0.028 hr-1) that are consistent with the inherent complexity associated with correct heme insertion and acylation of MtrC that occurs in the periplasm prior to its targeting to the outer membrane. These latter results suggest that MtrC protein trafficking to the outer membrane and its subsequent degradation are tightly regulated, which is consistent with cellular processing pathways that target MtrC to extracellular structures and their possible role in promoting electron transfer from Shewanella to extracellular acceptors.

Xiong, Yijia; Chen, Baowei; Shi, Liang; Fredrickson, Jim K.; Bigelow, Diana J.; Squier, Thomas C.

2011-10-14

187

MpeR Regulates the mtr Efflux Locus in Neisseria gonorrhoeae and Modulates Antimicrobial Resistance by an Iron-Responsive Mechanism  

PubMed Central

Previous studies have shown that the MpeR transcriptional regulator produced by Neisseria gonorrhoeae represses the expression of mtrF, which encodes a putative inner membrane protein (MtrF). MtrF works as an accessory protein with the Mtr efflux pump, helping gonococci to resist high levels of diverse hydrophobic antimicrobials. Regulation of mpeR has been reported to occur by an iron-dependent mechanism involving Fur (ferric uptake regulator). Collectively, these observations suggest the presence of an interconnected regulatory system in gonococci that modulates the expression of efflux pump protein-encoding genes in an iron-responsive manner. Herein, we describe this connection and report that levels of gonococcal resistance to a substrate of the mtrCDE-encoded efflux pump can be modulated by MpeR and the availability of free iron. Using microarray analysis, we found that the mtrR gene, which encodes a direct repressor (MtrR) of mtrCDE, is an MpeR-repressed determinant in the late logarithmic phase of growth when free iron levels would be reduced due to bacterial consumption. This repression was enhanced under conditions of iron limitation and resulted in increased expression of the mtrCDE efflux pump operon. Furthermore, as judged by DNA-binding analysis, MpeR-mediated repression of mtrR was direct. Collectively, our results indicate that both genetic and physiologic parameters (e.g., iron availability) can influence the expression of the mtr efflux system and modulate levels of gonococcal susceptibility to efflux pump substrates.

Mercante, Alexandra Dubon; Jackson, Lydgia; Johnson, Paul J. T.; Stringer, Virginia A.; Dyer, David W.

2012-01-01

188

Dose Rate Calculations of Spent MTR-HEU Fuel Elements of the IAN-R1 Research Reactor  

NASA Astrophysics Data System (ADS)

With cooperation of the International Atomic Energy Agency (IAEA) and the Department of Energy (DOE) of the United States, several tasks related to the waste disposal of spent MTR fuel enriched nominally to 93% were carried out for the conversion of the IAN-R1 Research Reactor from MTR-HEU fuel to TRIGA-LEU fuel. In order to remove the spent MTR-HEU fuel of the core and store it safetly, a program was established at the Instituto de Ciencias Nucleares y Energìas Alternativas (INEA). This program included training, acquisition of hardware and sofware, design and construction of a decay pool, transfer of the spent HEU fuel elements into the decay pool and his final transport to Savanah River in United States. In this paper are presented external dose rates which were calculated for a standard spent MTR-HEU fuel element of the IAN-R1 Research Reactor. The calculations take in consideration the activity due to contributions of fission, activation and actinides products for each relevant radionuclide present in a standard spent MTR-HEU fuel. The datas obtained were the base for the respective dosimetric evaluations in the transfering operations of fuel elements into the decay pool and for shielding calculations in designing of the decay pool.

Sarta Fuentes, Jose Antonio

2005-04-01

189

Radionuclide Compositions and Total Activity of Spent MTR-HEU Fuel Elements of the IAN-R1 Research Reactor  

NASA Astrophysics Data System (ADS)

With cooperation of the International Atomic Energy Agency (IAEA) and the Department of Energy (DOE) of the United States, several calculations and tasks related to the waste disposal of spent MTR fuel enriched nominally to 93% were carried out for the conversion of the IAN-R1 Research Reactor from MTR-HEU fuel to TRIGA-LEU fuel. In order to remove the spent MTR-HEU fuel of the core and store it safely a program was established at the Instituto de Ciencias Nucleares y Energìas Alternativas (INEA). This program included training, acquisition of hardware and software, design and construction of a decay pool, transfer of the spent HEU fuel elements into the decay pool and his final transport to Savannah River in United States. In this paper are presented data of activities calculated for each relevant radionuclide present in spent MTR-HEU fuel elements of the IAN-R1 Research Reactor and the total activity. The total activity calculated takes in consideration contributions of fission, activation and actinides products. The data obtained were the base for shielding calculations for the decay pool concerning the storage of spent MTR-HEU fuel elements and the respective dosimetric evaluations in the transferring operations of fuel elements into the decay pool.

Sarta, Josè A.; Castiblanco, Luis A.

2005-05-01

190

Direct Involvement of Type II Secretion System in Extracellular Translocation of Shewanella oneidensis Outer Membrane Cytochromes MtrC and OmcA?  

PubMed Central

MtrC and OmcA are cell surface-exposed lipoproteins important for reducing solid metal oxides. Deletions of type II secretion system (T2SS) genes reduced their extracellular release and their accessibility to the proteinase K treatment, demonstrating the direct involvement of T2SS in translocation of MtrC and OmcA to the bacterial cell surface.

Shi, Liang; Deng, Shuang; Marshall, Matthew J.; Wang, Zheming; Kennedy, David W.; Dohnalkova, Alice C.; Mottaz, Heather M.; Hill, Eric A.; Gorby, Yuri A.; Beliaev, Alexander S.; Richardson, David J.; Zachara, John M.; Fredrickson, James K.

2008-01-01

191

Decontamination and decommissioning of the MTR-603 HB-2 cubicle. Final report  

SciTech Connect

This report describes the decontamination and decommissioning (D and D) of the MTR-603 HB-2 cubicle located at the Idaho National Engineering Laboratory (INEL). The HB-2 cubicle became radioactively contaminated during out-of-pile circulating water loop experiments conducted in the Materials Testing Reactor in the 1950s and 1960s. This report describes work performed to accomplish the D and D objectives of reducing the high radiation fields caused by contamination inside the cubicle, preventing future contamination spread, and making about 1400 ftS of floor space available for reuse. D and D of the HB-2 cubicle consisted of total dismantlement of the cubicle and its contents.

Smith, D.L.

1985-12-01

192

Cloning, nucleotide sequence, and characterization of mtr, the structural gene for a tryptophan-specific permease of Escherichia coli K-12.  

PubMed Central

The mtr gene of Escherichia coli K-12 encodes an L-tryptophan-specific permease. This gene was originally identified through the isolation of mutations in the 69-min region of the chromosome, closely linked to argG. Cells with lesions in mtr display a phenotype of 5-methyltryptophan resistance. The mtr gene was cloned by using the mini-Mu system. The amino acid sequence of Mtr (414 codons), deduced by DNA sequence analysis, was found to be 33% identical to that of another single-component transport protein, the tyrosine-specific permease, TyrP. The hydropathy plots of the two permeases were similar. Possible operator sites for the tyrosine and tryptophan repressors are situated within the region of DNA that is likely to be the mtr promoter.

Heatwole, V M; Somerville, R L

1991-01-01

193

Decommissioning of the MTR-605 process water building at the Idaho National Engineering Laboratory. Final report  

SciTech Connect

Decontamination and decommissioning (D and D) of the unused radioactively contaminated portions of the MTR-605 building at the Test Reactor Area of the Idaho National Engineering Laboratory has been completed; this final report describes the D and D project. The building is a two-story concrete structure that was used to house piping systems to channel and control coolant water flow for the Materials Testing Reactor (MTR), a 40 MW (thermal) light water test reactor that was operated from 1952 until 1970 and then deactivated. D and D project objectives were to reduce potential environmental and radioactive contamination hazards to levels as low a reasonably achievable. Primary tasks of the D and D project were: to remove contaminated piping (about 400 linear ft of 36- and 30-in.-dia stainless steel pipe) and valves from the primary coolant pipe tunnels, to remove a primary coolant pump and piping, and to remove the three 8-ft-dia by 25-ft-long evaporators from the building second floor.

Browder, J.H.; Wills, E.L.

1985-01-01

194

Reactivity worth of the thermal column of a MTR type swimming pool research reactor using low enriched uranium fuel  

Microsoft Academic Search

The reactivity worth of the thermal column of a typical MTR type swimming pool research reactor using low enriched uranium fuel has been determined by modeling the core using standard computer codes. It was also measured experimentally by operating the reactor in the stall and open ends. The calculated value of the reactivity worth of the thermal column is about

Liaquat Ali Khan; Nasir Ahmad

2002-01-01

195

Influence of Combined Methionine Synthase (MTR 2756A > G) and Methylenetetrahydrofolate Reductase (MTHFR 677C > T) Polymorphisms to Plasma Homocysteine Levels in Korean Patients with Ischemic Stroke  

PubMed Central

Purpose Methionine synthase (MTR) and 5,10-methylenetetrahydrofolate reductase (MTHFR) are the main regulatory enzymes for homocysteine metabolism. The present case-control study was conducted to determine whether there is an association between the MTR 2756A > G or MTHFR 677C > T polymorphism and plasma homocysteine concentration in Korean subjects with ischemic stroke. Materials and Methods DNA samples of 237 patients who had an ischemic stroke and 223 age and sex-matched controls were studied. MTR 2756A > G and MTHFR 677C > T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results Frequencies of mutant alleles for MTR and MTHFR polymorphisms were not significantly different between the controls and cases. The patient group, however, had significantly higher homocysteine concentrations of the MTR 2756AA and MTHFR 677TT genotypes than the control group (p = 0.04 for MTR, p = 0.01 for MTHFR). The combined MTR 2756AA and MTHFR 677TT genotype (p = 0.04) and the homocysteine concentrations of the patient group were also higher than those of the controls. In addition, the genotype distribution was significant in the MTHFR 677TT genotype (p = 0.008) and combined MTR 2756AA and MTHFR 677TT genotype (p = 0.03), which divided the groups into the top 20% and bottom 20% based on their homocysteine levels. Conclusion The results of the present study demonstrate that the MTR 2756A > G and MTHFR 677C > T polymorphisms interact with elevated total homocysteine (tHcy) levels, leading to an increased risk of ischemic stroke.

Kim, Ok Joon; Hong, Sun Pyo; Ahn, Jung Yong; Hong, Seung Ho; Hwang, Tae Sun; Kim, Soo Ok; Yoo, Wangdon; Oh, Doyeun

2007-01-01

196

Molecular structure and free energy landscape for electron transport in the decahaem cytochrome MtrF.  

PubMed

The free energy profile for electron flow through the bacterial decahaem cytochrome MtrF has been computed using thermodynamic integration and classical molecular dynamics. The extensive calculations on two versions of the structure help to validate the method and results, because differences in the profiles can be related to differences in the charged amino acids local to specific haem groups. First estimates of reorganization free energies ? yield a range consistent with expectations for partially solvent-exposed cofactors, and reveal an activation energy range surmountable for electron flow. Future work will aim at increasing the accuracy of ? with polarizable forcefield dynamics and quantum chemical energy gap calculations, as well as quantum chemical computation of electronic coupling matrix elements. PMID:23176454

Breuer, Marian; Zarzycki, Piotr; Shi, Liang; Clarke, Thomas A; Edwards, Marcus J; Butt, Julea N; Richardson, David J; Fredrickson, James K; Zachara, John M; Blumberger, Jochen; Rosso, Kevin M

2012-12-01

197

Experimental determination of the self-absorption factor for MTR plates by passive gamma spectrometric measurement  

NASA Astrophysics Data System (ADS)

The measurement of the absolute activity or the mass of radioactive substances by gamma spectrometry needs to include a correction for the radiation absorption inside the source volume, the so-called self-absorption factor. It depends on geometry and material composition of the source, the detector geometry and on the geometrical arrangement of source and gamma radiation detector; it can be calculated if full information about all that is available. This article however describes how to determine the self-absorption factor from measurements if the radiation sources are plates of uranium fuel with typical parameters of nuclear fuel for MTR reactors and without using detail information on the source geometry, thus allowing easy inspection without relying on - potentially falsified - declarations on the internal properties of the fuel objects and without calculation.

Berndt, R.; Mortreau, P.

2011-07-01

198

Direct Involvement of Type II Secretion System in Extracellular Translocation of Shewanella Oneidensis Outer Membrane Cytochromes MtrC and OmcA  

SciTech Connect

Outer membrane decaheme c-type cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 are extracellular lipoproteins important for dissimilatory reduction of solid metal (hydr)oxides during anaerobic respiration. To investigate the roles of type II secretion system (T2S) in translocation of MtrC and OmcA across outer membrane, we measured the effects of deleting two T2S genes, gspD and gspG, on the secretion of MtrC and OmcA when cells were grown under anaerobic conditions. Deletion of gspD or gspG resulted in slightly yellowish supernatants, different from the pink supernatant of wild type (wt). Comparative proteomic analyses revealed that, although MtrC, OmcA and NrfA, a periplasmic nitrite reductase, were present the supernatants of wt and ?gspD mutant, their peptides counts were much lower in ?gspD than in wt. Subsequent analyses with heme-staining and Western blot not only confirmed that deletion of gspD or gspG reduced the abundances of MtrC and OmcA in the supernatants, but also revealed that the deletions consequently increased their abundances inside the cells. Complementation of ?gspG mutant with functional GspG could reverse the effects of deleting gspG on the colors of the supernatants and the abundances of MtrC and OmcA. In contrast, Western results showed that the abundance of NrfA was reduced in the supernatant and the cells of ?gspD mutant, suggesting that reduced NrfA in the periplasm, where MtrC and OmcA were accumulated, contributed to its reduction in the supernatant. Thus, our results demonstrate at the first time that T2S facilitates translocation of MtrC and OmcA across outer membrane.

Shi, Liang; Deng, Shuang; Marshall, Matthew J.; Wang, Zheming; Kennedy, David W.; Dohnalkova, Alice; Mottaz, Heather M.; Hill, Eric A.; Gorby, Yuri A.; Beliaev, Alex S.; Richardson, David J.; Zachara, John M.; Fredrickson, Jim K.

2008-08-01

199

Amino Acid Residues in the a-Subunit C-Terminal Domain of Escherichia coli RNA Polymerase Involved in Activation of Transcription from the mtr Promoter  

Microsoft Academic Search

To examine the role of the amino acid residues (between positions 258 and 275 and positions 297 and 298) of the a-subunit of RNA polymerase in TyrR-mediated activation of the mtr promoter, we have carried out in vitro transcription experiments using a set of mutant RNA polymerases with a supercoiled mtr template. Decreases in factor-independent transcription in vitro by mutant

JI YANG; KATSUHIKO MURAKAMI; H. CAMAKARIS; NOBUYUKI FUJITA; AKIRA ISHIHAMA; A. J. PITTARD

1997-01-01

200

Multi-target retrieval (MTR): the simultaneous retrieval of pressure, temperature and volume mixing ratio profiles from limb-scanning atmospheric measurements  

Microsoft Academic Search

In this paper we describe a retrieval approach for the simultaneous determination of the altitude distributions of p, T and VMR of atmospheric constituents from limb-scanning measurements of the atmosphere. This analysis method, named multi-target retrieval (MTR), has been designed and implemented in a computer code aimed at the analysis of MIPAS-ENVISAT observations; however, the concepts implemented in MTR have

B. M. Dinelli; D. Alpaslan; M. Carlotti; L. Magnani; M. Ridolfi

2004-01-01

201

Sources of variation in multi-centre brain MTR histogram studies: body-coil transmission eliminates inter-centre differences  

Microsoft Academic Search

Object: 1. Identify sources of variation affecting Magnetisation Transfer Ratio (MTR) histogram reproducibility between-centres. 2. Demonstrate complete elimination of inter-centre difference.\\u000a Materials and methods: Six principle sources of variation were summarised and analysed. These are:the imager coil used for radiofrequency (RF) transmission, imager stability, the shape and other parameters describing the Magnetisation Transfer (MT) pulse, the MT sequence used (including

P. S. Tofts; S. C. A. Steens; M. Cercignani; F. Admiraal-Behloul; P. A. M. Hofman; M. J. P. van Osch; W. M. Teeuwisse; D. J. Tozer; J. H. T. M. van Waesberghe; R. Yeung; G. J. Barker; M. A. van Buchem

2006-01-01

202

Analysis of partial and total flow blockage of a single fuel assembly of an MTR research reactor core  

Microsoft Academic Search

The main aim of the following study is to perform a safety analysis of the IAEA 10 MW MTR Pool type Research Reactor [IAEA-TECDOC-233, 1980. IAEA Research Reactor Core Conversion from the use of high-enriched uranium to the use of low enriched uranium fuels Guidebook] under flow blockage of a single Fuel Assembly (FA) conditions. Such event was rarely investigated

Martina Adorni; Anis Bousbia-Salah; Tewfik Hamidouche; Beniamino Di Maro; Franco Pierro; Francesco D’Auria

2005-01-01

203

Utilization of high-density fuel and beryllium elements for the neutron flux enhancement in typical MTR type research reactors  

Microsoft Academic Search

Pakistan Research Reactor-1 (PARR-1) is a typical MTR type swimming pool reactor utilizing low enriched uranium (LEU), i.e. 19.99% enriched in 235U, silicide dispersion fuel of density 3.28gU\\/cm3. This simulation study was conducted by employing the standard reactor physics simulation codes WIMS-D\\/4, CITATION, and a burnup analysis code FCAP along with a reactor thermal hydraulic simulation code PARET. The present

Rizwan Ahmed; Aslam; Nasir Ahmad; Mohammad Javed Khan; Mujahid Tanvir

2007-01-01

204

A study of reduction in fuel requirement and enhancement of neutron flux in typical MTR type research reactors  

Microsoft Academic Search

Pakistan Research Reactor-1 (PARR-1) is a typical swimming pool type MTR utilizing low enriched uranium (19.99% in 235U) silicide dispersion fuel of density 3.28gU\\/cm3. The benefits of loading available and upcoming higher density fuels in the existing PARR-1 core have been explored in this study with constraints of no change in the existing moderator\\/coolant channel width and existing reactor systems.

Rizwan Ahmed; Aslam; Nasir Ahmad; Mohammad Javed Khan; Abdul Manan

2007-01-01

205

Reconstruction of 3D Coronal Magnetic Structures from THEMIS/MTR and Hinode/SOT Vector Maps  

NASA Astrophysics Data System (ADS)

Coordinated campaigns using THEMIS, Hinode, and other instruments have allowed us to study the magnetic fields of faculae, filaments, and active regions. In a first case, we modelled the 3D magnetic field in a flaring active region with a nonlinear force-free field extrapolation, using magnetic vectors observed by THEMIS/MTR as boundary condition. In order to construct a consistent bottom boundary for the model, we first removed the 180 degree ambiguity of the transverse fields and minimized the force and torque in the observed vector fields. We found a twisted magnetic flux rope, well aligned with the polarity inversion line and a part of an H? filament, and located where a large flare is initiated about two hours later. In a second case, Hinode/SOT allowed us to detect fine flux concentrations in faculae, while MTR provided us with magnetic information at different levels in the atmosphere. The polarimetry analysis of the MTR and SOT data gave consistent results, using both UNNOFIT and MELANIE inversion codes.

Schmieder, B.; Guo, Y.; Aulanier, G.; Démoulin, P.; Török, T.; Bommier, V.; Wiegelmann, T.; Gosain, S.

2012-08-01

206

Electrochemical interaction of Shewanella oneidensis MR-1 and its outer membrane cytochromes OmcA and MtrC with hematite electrodes  

NASA Astrophysics Data System (ADS)

Bacterial metal reduction is an important biogeochemical process in anaerobic environments. An understanding of electron transfer pathways from dissimilatory metal-reducing bacteria (DMRB) to solid phase metal (hydr)oxides is important for understanding metal redox cycling in soils and sediments, for utilizing DMRB in bioremedation, and for developing technologies such as microbial fuel cells. Here we hypothesize that the outer membrane cytochromes OmcA and MtrC from Shewanella oneidensis MR-1 are the only terminal reductases capable of direct electron transfer to a hematite working electrode. Cyclic voltammetry (CV) was used to study electron transfer between hematite electrodes and protein films, S. oneidensis MR-1 wild-type cell suspensions, and cytochrome deletion mutants. After controlling for hematite electrode dissolution at negative potential, the midpoint potentials of adsorbed OmcA and MtrC were measured (-201 mV and -163 mV vs. Ag/AgCl, respectively). Cell suspensions of wild-type MR-1, deletion mutants deficient in OmcA (? omcA), MtrC (? mtrC), and both OmcA and MtrC (? mtrC-? omcA) were also studied; voltammograms for ? mtrC-? omcA were indistinguishable from the control. When the control was subtracted from the single deletion mutant voltammograms, redox peaks were consistent with the present cytochrome (i.e., ? omcA consistent with MtrC and ? mtrC consistent with OmcA). The results indicate that OmcA and MtrC are capable of direct electron exchange with hematite electrodes, consistent with a role as terminal reductases in the S. oneidensis MR-1 anaerobic respiratory pathway involving ferric minerals. There was no evidence for other terminal reductases operating under the conditions investigated. A Marcus-based approach to electron transfer kinetics indicated that the rate constant for electron transfer ket varies from 0.025 s -1 in the absence of a barrier to 63.5 s -1 with a 0.2 eV barrier.

Meitl, Leisa A.; Eggleston, Carrick M.; Colberg, Patricia J. S.; Khare, Nidhi; Reardon, Catherine L.; Shi, Liang

2009-09-01

207

Structural analysis reveals the characteristic features of Mtr4, a DExH helicase involved in nuclear RNA processing and surveillance  

PubMed Central

Mtr4 is a conserved RNA helicase that functions together with the nuclear exosome. It participates in the processing of structured RNAs, including the maturation of 5.8S ribosomal RNA (rRNA). It also interacts with the polyadenylating Trf4-Air2 heterodimer to form the so-called TRAMP (Trf4-Air2-Mtr4 Polyadenylation) complex. TRAMP is involved in exosome-mediated degradation of aberrant RNAs in nuclear surveillance pathways. We report the 2.9-? resolution crystal structure of Saccharomyces cerevisiae Mtr4 in complex with ADP and RNA. The structure shows a central ATPase core similar to that of other DExH helicases. Inserted in the DExH core is a region characteristic of Mtr4 orthologues that folds into an elongated stalk connected to a ?-barrel domain. This domain shows unexpected similarity to the KOW domain of L24, a ribosomal protein that binds 23S rRNA. We find that indeed the KOW domain of Mtr4 is able to bind in vitro transcribed tRNAiMet, suggesting it might assist in presenting RNA substrates to the helicase core. The interaction of Mtr4 with Trf4-Air2 is mediated not by the stalk/KOW insertion but by the DExH core. We find that in the context of the TRAMP complex, the DExH core functions independently in vitro as an RNA helicase and a protein-binding platform. Mtr4 has thus evolved specific structural and surface features to perform its multiple functions.

Weir, John R.; Bonneau, Fabien; Hentschel, Jendrik; Conti, Elena

2010-01-01

208

Enhancement of the dissolution of albendazole from pellets using MTR technique  

PubMed Central

Albendazole (ABZ), a broad-spectrum anthelmintic agent, is poorly absorbed after oral administration due to its low aqueous solubility. The aim of this study was to improve albendazole dissolution rate by formulating avicel pellets loaded with 10% w/w drug using extrusion/spheronization technique. In addition the wet masses were characterized by mix torque rheometry (MTR) prior to pelletization process. Different additives (i.e., lactose, Tween 80 and low molecular weight chitosan) were formulated with avicel to enhance the dissolution rate of ABZ from the produced pellets. Moreover, mix torque rheometer was used to quantitatively determine the suitable moisture content in the pastes before the extrusion process. The produced pellets were characterized for their ABZ content, particle size, particle shape, dissolution profile and thermal behaviors. The maximum consistencies (the peak torques) of the wet granules were obtained using 0.667–1.333 ml/g of water or water containing surfactant. Also, the produced pellets have size range from 1036 to 1246 ?m. The calculated drug RDR30 for 10%, 30% and 50% lactose concentrations were 1.08, 1.08 and 2.03, respectively, while that calculated for 10%, 30% and 50% w/w chitosan concentrations were 1.71, 3.62 and 3.62, respectively. The results revealed also that increasing the weight ratio of lactose and chitosan was accompanied by a significant reduction of the peak torque magnitude and this was accompanied by an enhanced ABZ dissolution rate.

Ibrahim, Mohamed A.; Al-Anazi, Fars K.

2012-01-01

209

Search for polarimetric sensitivity in the first observations with THEMIS spectropolarimetric mode MTR (August 1998 campaign)  

NASA Astrophysics Data System (ADS)

The present paper is devoted to the search for the polarimetric sensitivity level in observations of the Fe I 5576 Å line performed with the THEMIS spectropolarimetric mode MTR on August 23 1998. This line is insensitive to the Zeeman effect and the present work is thus useful to calibration purposes. The upper level of the line is unpolarizable (J=0) and insensitive to the Hanle effect, and the observations have been performed at disk center to avoid any scattering polarization of lower level atomic polarization origin. In the present paper, we describe the steps of a method that is the basis of a data reduction code implemented on systems at the Meudon Observatory for the interpretation of observations where a large number ( ~ 150) of images are averaged, and where the signal is in addition averaged along the slit. First, we describe the numerical methods used to determine the line position in the images, and to perform operations on the profiles by FFT techniques (such as translation, dilation, defocusing, apodization). Then, the preprocessing steps are described: dark current subtraction, destretching and flat-field correction. The polarization analysis is then performed, based on the idea that, as the flat-field images are unpolarized, they can be used to correct spurious polarization occuring in the observations. As a result, the observed line is found to be unpolarized, and a sensitivity of 2-4x 10-4 is found for the polarization degree in the neighboring continuum.

Bommier, V.; Rayrole, J.

2002-01-01

210

Out Flow in a Virtual Mtr Station Using a Local View Floor Field Model  

NASA Astrophysics Data System (ADS)

The floor field (FF) model, up until now, has been the most widely used simulation in pedestrian flow dynamics for simple based scenarios. This paper presents an improvement on and upon the local view FF model by simulating pedestrian flow in more complex scenarios with typical goals and obstacles that may block or assist the sight of the pedestrian. In addition this model will also provide a detailed analysis entailing the simulation of multi-goal selections. This involves the visibility information on each cell being set, and a dynamic priority list of goals for every pedestrian being updated as he/she moves. The pedestrians select the convenient goal according to the priority of goals, the distances to the candidate goals and the degree of congestion. To aid in the theory of this and to make a better understanding of reality, a simulation scenario is conducted on a virtual MTR station, where parameter settings are discussed and some regular phenomena helpful to the designers of stations is put forward.

Leng, Biao; Wang, Jianyuan; Zhao, Xiaoxi; Fang, Jun; Xiong, Zhang

2013-06-01

211

Periplasmic Electron Transfer via the c-Type Cytochromes MtrA and FccA of Shewanella oneidensis MR-1 ?  

PubMed Central

Dissimilatory microbial reduction of insoluble Fe(III) oxides is a geochemically and ecologically important process which involves the transfer of cellular, respiratory electrons from the cytoplasmic membrane to insoluble, extracellular, mineral-phase electron acceptors. In this paper evidence is provided for the function of the periplasmic fumarate reductase FccA and the decaheme c-type cytochrome MtrA in periplasmic electron transfer reactions in the gammaproteobacterium Shewanella oneidensis. Both proteins are abundant in the periplasm of ferric citrate-reducing S. oneidensis cells. In vitro fumarate reductase FccA and c-type cytochrome MtrA were reduced by the cytoplasmic membrane-bound protein CymA. Electron transfer between CymA and MtrA was 1.4-fold faster than the CymA-catalyzed reduction of FccA. Further experiments showing a bidirectional electron transfer between FccA and MtrA provided evidence for an electron transfer network in the periplasmic space of S. oneidensis. Hence, FccA could function in both the electron transport to fumarate and via MtrA to mineral-phase Fe(III). Growth experiments with a ?fccA deletion mutant suggest a role of FccA as a transient electron storage protein.

Schuetz, Bjoern; Schicklberger, Marcus; Kuermann, Johannes; Spormann, Alfred M.; Gescher, Johannes

2009-01-01

212

MTR-Fill: A Simulated Annealing-Based X-Filling Technique to Reduce Test Power Dissipation for scan-Based Designs  

NASA Astrophysics Data System (ADS)

This paper proposes the minimum transition random X-filling (MTR-fill) technique, which is a new X-filling method, to reduce the amount of power dissipation during scan-based testing. In order to model the amount of power dissipated during scan load/unload cycles, the total weighted transition metric (TWTM) is introduced, which is calculated by the sum of the weighted transitions in a scan-load of a test pattern and a scan-unload of a test response. The proposed MTR-fill is implemented by simulated annealing method. During the annealing process, the TWTM of a pair of test patterns and test responses are minimized. Simultaneously, the MTR-fill attempts to increase the randomness of test patterns in order to reduce the number of test patterns needed to achieve adequate fault coverage. The effectiveness of the proposed technique is shown through experiments for ISCAS' 89 benchmark circuits.

Song, Dong-Sup; Ahn, Jin-Ho; Kim, Tae-Jin; Kang, Sungho

213

Kinetic study of fission product activity released inside containment under loss of coolant transients in a typical MTR system.  

PubMed

Based on continuous release of fission product (FP) activity from fuel to the coolant and then to the containment, a kinetic model is developed for source term after a LOCA in a typical MTR type system. The time dependent source, re-suspension rate, decay of fission products, leakage, deposition on surfaces, and re-circulation of air through filters are employed with a partial prompt source plus a time varying source. Releases of different FP activities are simulated for various release rates. PMID:23041390

Awan, Saeed E; Mirza, Nasir M; Mirza, Sikander M

2012-12-01

214

Loss of the mtr operon in Methanosarcina blocks growth on methanol, but not methanogenesis, and reveals an unknown methanogenic pathway  

Microsoft Academic Search

In the methanogenic archaeon Methanosarcina barkeri Fusaro, the N5-methyl-tetrahydrosarcinapterin (CH3-H4SPT):coenzyme M (CoM) methyltransferase, encoded by the mtr operon, catalyzes the energy-conserving (sodium-pumping) methyl transfer from CH3-H4SPT to CoM during growth on H2\\/CO2 or acetate. However, in the disproportionation of C-1 compounds, such as methanol, to methane and carbon dioxide, it catalyzes the reverse, endergonic transfer from methyl-CoM to H4SPT, which

Paula V. Welander; William W. Metcalf

2005-01-01

215

Venus wind map at cloud top level with the MTR/THEMIS visible spectrometer, I: Instrumental performance and first results  

NASA Astrophysics Data System (ADS)

Solar light gets scattered at cloud top level in Venus' atmosphere, in the visible range, which corresponds to the altitude of 67 km. We present Doppler velocity measurements performed with the high resolution spectrometer MTR of the Solar telescope THEMIS (Teide Observatory, Canary Island) on the sodium D2 solar line (5890A?). Observations lasted only 49 min because of cloudy weather. However, we could assess the instrumental velocity sensitivity, 31ms-1 per pixel of 1 arcsec, and give a value of the amplitude of zonal wind at equator at 151±16ms-1.

Gaulme, Patrick; Schmider, François-Xavier; Grec, Catherine; López Ariste, Arturo; Widemann, Thomas; Gelly, Bernard

2008-08-01

216

Characterization of Axial and Proximal Histidine Mutations of the Decaheme Cytochrome MtrA from Shewanella sp. Strain ANA-3 and Implications for the Electron Transport System  

PubMed Central

Extracellular respiration of solid-phase electron acceptors in some microorganisms requires a complex chain of multiheme c-type cytochromes that span the inner and outer membranes. In Shewanella species, MtrA, an ?35-kDa periplasmic decaheme c-type cytochrome, is an essential component for extracellular respiration of iron(III). The exact mechanism of electron transport has not yet been resolved, but the arrangement of the polypeptide chain may have a strong influence on the capability of the MtrA cytochrome to transport electrons. The iron hemes of MtrA are bound to its polypeptide chain via proximal (CXXCH) and distal histidine residues. In this study, we show the effects of mutating histidine residues of MtrA to arginine on protein expression and extracellular respiration using Shewanella sp. strain ANA-3 as a model organism. Individual mutations to six out of nine proximal histidines in CXXCH of MtrA led to decreased protein expression. However, distal histidine mutations resulted in various degrees of protein expression. In addition, the effects of histidine mutations on extracellular respiration were tested using ferrihydrite and current production in microbial fuel cells. These results show that proximal histidine mutants were unable to reduce ferrihydrite. Mutations to the distal histidine residues resulted in various degrees of ferrihydrite reduction. These findings indicate that mutations to the proximal histidine residues affect MtrA expression, leading to loss of extracellular respiration ability. In contrast, mutations to the distal histidine residues are less detrimental to protein expression, and extracellular respiration can proceed.

Qian, Fang; Zhang, Alissa; Bondarev, Sergey; Welch, Angel; Thelen, Michael P.

2012-01-01

217

Some THEMIS-MTR observations of the second solar spectrum (2000 campaign)  

NASA Astrophysics Data System (ADS)

We report spectropolarimetric observations with the THEMIS telescope multi-lines operating mode (MTR) during the 2000 observational period from August 27th to September 1st. We measured the resonance polarization at the limb of a series of lines: Sr I 460.7 nm, Na I D1 589.6 nm and D2 589.0 nm, Ba Ii D1 493.4 nm and D2 455.4 nm, C I 493.2 nm. The data analysis method is mainly described in Bommier & Rayrole (\\cite{Bommier-Rayrole-01}), and has been completed by using the beam exchange facility as available in 2000 THEMIS, i.e., in a single Stokes parameter. A so-called ``generalized beam exchange'' technique has been settled on, for the full Stokes vector measurement under this limitation. The observations have been devoted to the measurement of the scattering polarization which is a linear polarization observed near the limb of the Quiet Sun, eventually modified by a weak magnetic field (the so-called Hanle effect). The entrance slit of the spectrograph has been oriented parallel to the tangential direction of the solar limb, and data have been averaged in time and along the spatial direction of the slit in order to increase the polarimetric resolution. Two different cameras have been used to record simultaneously the two polarization states exiting the beam-splitter. The results of our polarization measurements are in good agreement with those given in the second spectrum solar atlas of Gandorfer (\\cite{Gandorfer-00}), based on 1999-2000 observations. Nevertheless, with regard to a quantification of the polarization signal, we found that the signal is systematically smaller than previous results obtained during the 1994-96 observational period and was also observed as decreasing during the 1998 observational period, as if a 11-year cyclic variation of the limb polarization occured. This signal variability obviously requires further observational and interpretative investigations. We noticed other differences to previous results, in particular, the linear polarization shape of the Na I D1 line that also requires further observational investigation. Based on observations made with THEMIS operated on the island of Tenerife by CNRS-CNR in the Spanish Observatorio del Teide of the Instituto de Astrofísica de Canarias.

Bommier, V.; Molodij, G.

2002-01-01

218

In Vivo Identification of the Outer Membrane Protein OmcA-MtrC Interaction Network in Shewanella oneidensis MR-1 Cells Using Novel Hydrophobic Chemical Cross-Linkers  

PubMed Central

Outer membrane (OM) cytochromes OmcA (SO1779) and MtrC (SO1778) are the integral components of electron transfer used by Shewanella oneidensis for anaerobic respiration of metal (hydr)oxides. Here the OmcA–MtrC interaction was identified in vivo using a novel hydrophobic chemical cross-linker (MRN) combined with immunoprecipitation techniques. In addition, identification of other OM proteins from the cross-linked complexes allows first visualization of the OmcA–MtrC interaction network. Further experiments on omcA and mtrC mutant cells showed OmcA plays a central role in the network interaction. For comparison, two commercial cross-linkers were also used in parallel, and both resulted in fewer OM protein identifications, indicating the superior properties of MRN for identification of membrane protein interactions. Finally, comparison experiments of in vivo cross-linking and cell lysate cross-linking resulted in significantly different protein interaction data, demonstrating the importance of in vivo cross-linking for study of protein–protein interactions in cells.

Zhang, Haizhen; Tang, Xiaoting; Munske, Gerhard R.; Zakharova, Natalia; Yang, Li; Zheng, Chunxiang; Wolff, Megan A.; Tolic, Nikola; Anderson, Gordon A.; Shi, Liang; Marshall, Matthew J.; Fredrickson, James K.; Bruce, James E.

2008-01-01

219

Assurance of Fabrication Technology for MTR Fuel Elements with Low-Enriched Uranium in a First LEU Core of a West German Research Reactor, Project 12. Final Report.  

National Technical Information Service (NTIS)

R and D work is reported that accompanied the process engineering work for the fabrication of MTR fuel elements with low U-235 enrichment, results to be used for the design of the series production process. The fabrication of the fuel elements for a first...

K. H. Koch M. Mueller

1988-01-01

220

In Vivo Identification of the Outer Membrane Protein OmcA-MtrC Interaction Network in Shewanella oneidensis MR-1 Cells Using Novel Hydrophobic Chemical Cross-Linkers  

SciTech Connect

Outer membrane (OM) cytochromes OmcA (SO1779) and MtrC (SO1778) are the integral components of electron transfer used by Shewanella oneidensis for anaerobic respiration of metal (hydr)oxides. Here the OmcA-MtrC interaction was identified in vivo using a novel hydrophobic chemical cross-linker (MRN) combined with immunoprecipitation techniques. In addition, identification of other OM proteins from the cross-linked complexes allows first visualization of the OmcA-MtrC interaction network. Further experiments on omcA and mtrC mutant cells showed OmcA plays a central role in the network interaction. For comparison, two commercial cross-linkers were also used in parallel and both resulted in fewer OM protein identifications, indicating the superior properties of MRN for identification of membrane protein interactions. Finally, comparison experiments of in vivo cross-linking and cell lysate cross-linking resulted in significantly different protein interaction data, demonstrating the importance of in vivo cross-linking for study of protein-protein interactions in cells.

Zhang, Haizhen; Tang, Xiaoting; Munske, Gerhard R.; Zakharova, Natalia L.; Yang, Li; Zheng, Chunxiang; Wolff, Meagan A.; Tolic, Nikola; Anderson, Gordon A.; Shi, Liang; Marshall, Matthew J.; Fredrickson, Jim K.; Bruce, James E.

2008-04-01

221

Certain Adenylated Non-Coding RNAs, Including 5? Leader Sequences of Primary MicroRNA Transcripts, Accumulate in Mouse Cells following Depletion of the RNA Helicase MTR4  

PubMed Central

RNA surveillance plays an important role in posttranscriptional regulation. Seminal work in this field has largely focused on yeast as a model system, whereas exploration of RNA surveillance in mammals is only recently begun. The increased transcriptional complexity of mammalian systems provides a wider array of targets for RNA surveillance, and, while many questions remain unanswered, emerging data suggest the nuclear RNA surveillance machinery exhibits increased complexity as well. We have used a small interfering RNA in mouse N2A cells to target the homolog of a yeast protein that functions in RNA surveillance (Mtr4p). We used high-throughput sequencing of polyadenylated RNAs (PA-seq) to quantify the effects of the mMtr4 knockdown (KD) on RNA surveillance. We demonstrate that overall abundance of polyadenylated protein coding mRNAs is not affected, but several targets of RNA surveillance predicted from work in yeast accumulate as adenylated RNAs in the mMtr4KD. microRNAs are an added layer of transcriptional complexity not found in yeast. After Drosha cleavage separates the pre-miRNA from the microRNA's primary transcript, the byproducts of that transcript are generally thought to be degraded. We have identified the 5? leading segments of pri-miRNAs as novel targets of mMtr4 dependent RNA surveillance.

Dorweiler, Jane E.; Ni, Ting; Zhu, Jun; Munroe, Stephen H.; Anderson, James T.

2014-01-01

222

Role of Outer-Membrane Cytochromes MtrC and OmcA in the Biomineralization of Ferrihydrite by Shewanella oneidensis MR-1.  

SciTech Connect

In an effort to improve the understanding of electron transfer mechanisms at the microbe-mineral interface, Shewanella oneidensis MR-1 mutants with in-frame deletions of outer membrane cytochrome genes mtrC, omcA, or both, were characterized for the ability to reduce metal oxides using a suite of microscopic, spectroscopic, and biochemicalr techniques. The results indicate that neither MtrC nor OmcA are essential for the reduction of soluble, complexed Fe(III)-citrate or Fe(III)-NTA; however, at least one of these outer membrane cytochromes is required for the reduction of Fe(III)- and Mn(III/IV)- oxides. In vitro analysis of purified, recombinant protein demonstrated that both cytochromes transfer electrons directly to metal-oxides; however, MtrC transfers electrons at a faster rate than OmcA. Immunolocalization of MtrC and OmcA reveal that both cytochromes are surface-exposed on the cell outer-membrane and co-localize with insoluble iron precipitates when respiring ferrihydrite or cultured aerobically with Fe(III)-citrate. Additionally, during prolonged incubation, wild-type cells promoted biotransformation of ferrihydrite to vivianite [Fe3(PO4)2•8H2O] while the double cytochrome mutant was unable to form any secondary mineral phases. Collectively, our results support a role for direct electron transfer from OMCs to metal oxides by establishing their in vitro electron transfer activities, confirming the requirement of either MtrC or OmcA for in vivo reductive biomineralization of ferrihydrite, and localizing the cytochromes to the cell exterior where they can directly contact mineral substrates.

Reardon, Catherine L.; Dohnalkova, Alice; Nachimuthu, Ponnusamy; Kennedy, David W.; Saffarini, Daad; Arey, Bruce W.; Shi, Liang; Wang, Zheming; Moore, Dean A.; Mclean, Jeffrey S.; Moyles, Dianne M.; Marshall, Matthew J.; Zachara, John M.; Fredrickson, Jim K.; Beliaev, Alex S.

2010-01-01

223

C1D and hMtr4p associate with the human exosome subunit PM/Scl-100 and are involved in pre-rRNA processing  

PubMed Central

The exosome is a complex of 3?–5? exoribonucleases and RNA-binding proteins, which is involved in processing or degradation of different classes of RNA. Previously, the characterization of purified exosome complexes from yeast and human cells suggested that C1D and KIAA0052/hMtr4p are associated with the exosome and thus might regulate its functional activities. Subcellular localization experiments demonstrated that C1D and KIAA0052/hMtr4p co-localize with exosome subunit PM/Scl-100 in the nucleoli of HEp-2 cells. Additionally, the nucleolar accumulation of C1D appeared to be dependent on PM/Scl-100. Protein–protein interaction studies showed that C1D binds to PM/Scl-100, whereas KIAA0052/hMtr4p was found to interact with MPP6, a previously identified exosome-associated protein. Moreover, we demonstrate that C1D, MPP6 and PM/Scl-100 form a stable trimeric complex in vitro. Knock-down of C1D, MPP6 and KIAA0052/hMtr4p by RNAi resulted in the accumulation of 3?-extended 5.8S rRNA precursors, showing that these proteins are required for rRNA processing. Interestingly, C1D appeared to contain RNA-binding activity with a potential preference for structured RNAs. Taken together, our results are consistent with a role for the exosome-associated proteins C1D, MPP6 and KIAA052/hMtr4p in the recruitment of the exosome to pre-rRNA to mediate the 3? end processing of the 5.8S rRNA.

Schilders, Geurt; van Dijk, Erwin; Pruijn, Ger J.M.

2007-01-01

224

The MTR 2756A>G polymorphism and maternal risk of birth of a child with Down syndrome: a case-control study and a meta-analysis.  

PubMed

Methionine synthase (MTR) is required for the conversion of homocysteine (hcy) to methionine in the one-carbon metabolic pathway. Previous studies investigating a common MTR 2756A>G polymorphism as a maternal risk factor for the birth of a child with Down syndrome (DS) are conflicting and limited by small case-control cohorts, and its contribution to circulating hcy levels is still debated. We performed a large case-control study and a meta-analysis of the literature to further address the role of MTR 2756A>G as a maternal risk factor for the birth of a child with DS. 286 mothers of a DS child (MDS) and 305 control mothers of Italian origin were included in the case-control study. Genotyping was performed by means of PCR/RFLP technique. Data on circulating levels of hcy, folates, and vitamin B12 were available for 189 MDS and 194 control mothers. The meta analysis of previous and present data involved a total of 8 studies (1,171 MDS and 1,402 control mothers). Both the case-control study and the meta-analysis showed no association of MTR 2756A>G with the maternal risk of birth of a child with DS (OR = 1.15; 95 % CI 0.85-1.55, and OR = 1.08; 95 % CI 0.93-1.25, respectively), even after stratification of the overall data available for the meta-analysis into ethnic groups. No association of the studied polymorphism with circulating levels of hcy, folates, and vitamin B12 was observed. Present data do not support a role for MTR 2756A>G as independent maternal risk factor for a DS birth. PMID:24150725

Coppedè, Fabio; Bosco, Paolo; Lorenzoni, Valentina; Migheli, Francesca; Barone, Concetta; Antonucci, Ivana; Stuppia, Liborio; Romano, Corrado; Migliore, Lucia

2013-12-01

225

The characterization of conserved binding motifs and potential target genes for M. tuberculosis MtrAB reveals a link between the two-component system and the drug resistance of M. smegmatis  

Microsoft Academic Search

BACKGROUND: The two-component systems of Mycobacterium tuberculosis are apparently required for its growth and resistance in hostile host environments. In such environments, MtrAB has been reported to regulate the expression of the M. tuberculosis replication initiator gene, dnaA. However, the dnaA promoter binding sites and many potential target genes for MtrA have yet to be precisely characterized. RESULTS: In this

Yuqing Li; Jumei Zeng; Hua Zhang; Zheng-Guo He

2010-01-01

226

Kinetics of Reduction of Fe(III) Complexes by Outer Membrane Cytochromes MtrC and OmcA of Shewanella oneidensis MR1  

Microsoft Academic Search

Shewanella Oneidensis MR-1 possesses up to 42 c-type cytochromes with heme content varying between 1 to as many as 37. Among them, the outer-membrane cytochromes, particularly MtrC and OmcA, are suspected to function as terminal reductases and are responsible for its enzymatic catalysis capability. So far, the mechanisms of metal reduction by these outer-membrane cytochromes are unknown. In this work,

Zheming Wang; Chongxuan Liu; Xuelin Wang; Matthew J. Marshall; John M. Zachara; Kevin M. Rosso; Michel Dupuis; James K. Fredrickson; Steve M. Heald; Liang Shi

2008-01-01

227

Turbo-EEPRML: An EEPR4 channel with an error-correcting post-processor designed for 16\\/17 rate quasi-MTR code  

Microsoft Academic Search

An EEPRML channel with a post processor has been developed for compensating for the degradation in performance due to noise correlation. This Turbo-EEPRML is designed for 16\\/17 rate quasi-MTR (QMTR) code. The proposed method has high performance and simple circuitry. Simulation showed that Turbo-EEPRML has a 2.0-2.5 dB coding gain over a conventional EPRML channel for 16\\/17 GCR code

Takushi Nishiya; Kyoko Tsukano; T. Hirai; Takashi Nara; Seiichi Mita

1998-01-01

228

Tudor-related proteins TDRD1\\/MTR-1, TDRD6 and TDRD7\\/TRAP: Domain composition, intracellular localization, and function in male germ cells in mice  

Microsoft Academic Search

The germ-line cells of many animals possess a characteristic cytoplasmic structure termed nuage or germinal granules. In mice, nuage that is prominent in postnatal male germ cells is also called intermitochondrial cement or chromatoid bodies. TDRD1\\/MTR-1, which contains Tudor domain repeats, is a specific component of the mouse nuage, analogously to Drosophila Tudor, a constituent of polar granules\\/nuage in oocytes

Mihoko Hosokawa; Masanobu Shoji; Kouichi Kitamura; Takashi Tanaka; Toshiaki Noce; Shinichiro Chuma; Norio Nakatsuji

2007-01-01

229

A New d=1, k=10 Soft-Decodable RLL Code with r=2 MTR-Constraint and a 2-to-3 PCWA Mapping for DC-Control  

Microsoft Academic Search

The proposed 1102PC code is a new d=1 RLL code with a compact 2-to-3 PCWA-mapping for DC-control that offers a significant performance benefit over traditional soft-decodable d=1, k=7 codes thanks to the reduced occurrence of the shortest 2T-runs as realized via an r=2 MTR-constraint; in addition, it still offers a low k-constraint (k=10) and a SISO-complexity much lower than that

W. Coene; A. Hekstra; B. Yin; H. Yamagishi; M. Noda; A. Nakaoki; T. Horigome

2006-01-01

230

Mouse Tudor Repeat1 (MTR-1) is a novel component of chromatoid bodies\\/nuages in male germ cells and forms a complex with snRNPs  

Microsoft Academic Search

Characteristic ribonucleoprotein-rich granules, called nuages, are present in the cytoplasm of germ-line cells in many species. In mice, nuages are prominent in postnatal meiotic spermatocytes and postmeiotic round spermatids, and are often called chromatoid bodies at the stages. We have isolated Mouse tudor repeat-1 (Mtr-1) which encodes a MYND domain and four copies of the tudor domain. Multiple tudor domains

Shinichiro Chuma; Masateru Hiyoshi; Akitsugu Yamamoto; Mihoko Hosokawa; Kazufumi Takamune; Norio Nakatsuji

2003-01-01

231

MtrB Is Required for Proper Incorporation of the Cytochromes OmcA and OmcB into the Outer Membrane of Shewanella putrefaciens MR-1  

PubMed Central

When grown under anaerobic conditions, Shewanella putrefaciens MR-1 synthesizes multiple outer membrane (OM) cytochromes, some of which have a role in the use of insoluble electron acceptors (e.g., MnO2) for anaerobic respiration. The cytochromes OmcA and OmcB are localized to the OM and the OM-like intermediate-density membrane (IM) in MR-1. The components necessary for proper localization of these cytochromes to the OM have not been identified. A gene replacement mutant (strain MTRB1) lacking the putative OM protein MtrB was isolated and characterized. The specific cytochrome content of the OM of MTRB1 was only 36% that of MR-1. This was not the result of a general decline in cytochrome content, however, because the cytoplasmic membrane (CM) and soluble fractions were not cytochrome deficient. While OmcA and OmcB were detected in the OM and IM fractions of MTRB1, significant amounts were mislocalized to the CM. OmcA was also detected in the soluble fraction of MTRB1. While OmcA and OmcB in MR-1 fractions were resistant to solubilization with Triton X-100 in the presence of Mg2+, Triton X-100 readily solubilized these proteins from all subcellular fractions of MTRB1. Together, these data suggest that MtrB is required for the proper localization and insertion of OmcA and OmcB into the OM of MR-1. The inability of MTRB1 to properly insert these, and possibly other, proteins into its OM likely contributes to its marked deficiency in manganese(IV) and iron(III) reduction. While the localization of another putative OM cytochrome (MtrF) could not be directly determined, an mtrF gene replacement mutant exhibited wild-types rates of Mn(IV) and Fe(III) reduction. Therefore, even if MtrF were mislocalized in MTRB1, it would not contribute to the loss of metal reduction activity in this strain.

Myers, Charles R.; Myers, Judith M.

2002-01-01

232

Effects of Bio-Au Nanoparticles on Electrochemical Activity of Shewanella oneidensis Wild Type and ?omcA/mtrC Mutant  

PubMed Central

Both Shewanella oneidensis MR-1 wild type and its mutant ?omcA/mtrC are capable of transforming AuIII into Au nanoparticles (AuNPs). Cyclic voltammetry reveals a decrease in redox current after the wild type is exposed to AuIII but an increase in oxidation current for the mutant. The peak current of the wild type is much higher than that of the mutant before the exposure of AuIII, but lower than that of the mutant after the formation of AuNPs. This suggests that damage to the electron transfer chain in the mutant could be repaired by AuNPs to a certain extent. Spectroscopy and SDS-PAGE analysis indicate a decrease in cell protein content after the formation of AuNPs, which provides a convenient way to detect intracellular information on cells.

Wu, Ranran; Cui, Li; Chen, Lixiang; Wang, Chao; Cao, Changli; Sheng, Guoping; Yu, Hanqing; Zhao, Feng

2013-01-01

233

Defects in mTR stability and telomerase activity produced by the Dkc1 A353V mutation in dyskeratosis congenita are rescued by a peptide from the dyskerin TruB domain  

PubMed Central

The predominant X-linked form of Dyskeratosis congenita results from mutations in dyskerin, a protein required for ribosomal RNA modification that is also a component of the telomerase complex. We have previously found that expression of an internal fragment of dyskerin (GSE24.2) rescues telomerase activity in X-linked dyskeratosis congenita (X-DC) patient cells. Here we have generated F9 mouse cell lines expressing the most frequent mutation found in X-DC patients, A353V and investigate the effect of expressing the GSE24.2 cDNA or GSE24.2 peptide on telomerase activity, mTERT and mTR expression. Expression of GSE24.2 increases mTR and to a lesser extent mTERT RNA levels and leads to recovery of telomerase activity. Point mutations in GSE24.2 residues known to be highly conserved and crucial for the pseudouridine-synthase activity of dyskerin abolished the effect of the peptide. Recovery of telomerase activity and increase in mTERT levels were found when the GSE24.2 peptide purified from bacteria was introduced into the cells Moreover mTR stability was also rescued by transfection of the peptide GSE24.2. These data indicate that supplying GSE24.2, either from a cDNA vector, or as a peptide, can reduce the pathogenic effects of Dkc1 mutations and could form the basis of a novel therapeutic approach.

Machado-Pinilla, R; Carrillo, J.; Manguan-Garcia, C; Sastre, L; Mentzer, A; Gu, B-W; Mason, PJ; Perona, R

2013-01-01

234

Polymorphisms in MTHFR, MS and CBS Genes and Homocysteine Levels in a Pakistani Population  

PubMed Central

Background Hyperhomocysteinemia (>15 µmol/L) is highly prevalent in South Asian populations including Pakistan. In order to investigate the genetic determinants of this condition, we studied 6 polymorphisms in genes of 3 enzymes - methylenetetrahydrofolate reductase (MTHFR; C677T; A1298C), methionine synthase (MS; A2756G), cystathionine-?-synthase (CBS; T833C/844ins68, G919A) involved in homocysteine metabolism and investigated their interactions with nutritional and environmental factors in a Pakistani population. Methodology/Principal Findings In a cross-sectional survey, 872 healthy adults (355 males and 517 females; age 18–60 years) were recruited from a low-income urban population in Karachi. Fasting venous blood was obtained and assessed for plasma/serum homocysteine; folate, vitamin B12, pyridoxal phosphate and blood lead. DNA was isolated and genotyping was performed by PCR-RFLP (restriction-fragment-length- polymorphism) based assays. The average changes in homocysteine levels for MTHFR 677CT and TT genotypes were positive [?(SE ?), 2.01(0.63) and 16.19(1.8) µmol/L, respectively]. Contrary to MTHFR C677T polymorphism, the average changes in plasma homocysteine levels for MS 2756AG and GG variants were negative [?(SE ?), ?0.56(0.58) and ?0.83(0.99) µmol/L, respectively]. The average change occurring for CBS 844ins68 heterozygous genotype (ancestral/insertion) was ?1.88(0.81) µmol/L. The combined effect of MTHFR C677T, MS A2756G and CBS 844ins68 genotypes for plasma homocysteine levels was additive (p value <0.001). Odds of having hyperhomocysteinemia with MTHFR 677TT genotype was 10-fold compared to MTHFR 677CC genotype [OR (95%CI); 10.17(3.6–28.67)]. Protective effect towards hyperhomocysteinemia was observed with heterozygous (ancestral/insertion) genotype of CBS 844ins68 compared to homozygous ancestral type [OR (95% CI); 0.58 (0.34–0.99)]. Individuals with MTHFR 677CT or TT genotypes were at a greater risk of hyperhomocysteinemia in folate and vitamin B12 deficiencies and high blood lead (p value <0.05) level. Conclusions Gene polymorphism (especially MTHFR C677T transition), folate and vitamin B12 deficiencies, male gender and high blood lead level appear to be contributing towards the development of hyperhomocysteinemia in a Pakistani population.

Yakub, Mohsin; Moti, Naushad; Parveen, Siddiqa; Chaudhry, Bushra; Azam, Iqbal; Iqbal, Mohammad Perwaiz

2012-01-01

235

Evaluation of Heterogeneity in the Association between Congenital Heart Defects and Variants of Folate Metabolism Genes: Conotruncal and Left-Sided Cardiac Defects  

PubMed Central

PURPOSE Genetic variation in the folate metabolic pathway may influence the risk of congenital heart defects. This study was undertaken to assess the associations between the inherited and maternal genotypes for variants in folate-related genes and the risk of a composite heart phenotype that included two component phenotypes: conotruncal heart defects (CTDs) and left-sided cardiac lesions (LSLs). METHODS Nine folate-related gene variants were evaluated using data from 692 case-parent triads (CTD, n=419; LSL, n=273). Log-linear analyses were used to test for heterogeneity of the genotype-phenotype association across the two component phenotypes (i.e. CTD and LSLS) and, when there was no evidence of heterogeneity, to assess the associations of the maternal and inherited genotypes with the composite phenotype. RESULTS There was little evidence of heterogeneity of the genotype-phenotype association across the two component phenotypes or of an association between the genotypes and the composite phenotype. There was evidence of heterogeneity in the association of the maternal MTR A2756G genotype (p = 0.01) with CTDs and LSLs. However, further analyses suggested that the observed associations with the maternal MTR A2756G genotype might be confounded by parental imprinting effects. CONCLUSIONS Our analyses of these data provide little evidence that the folate-related gene variants evaluated in this study influence the risk of this composite congenital heart defect phenotype. However, larger and more comprehensive studies that evaluate parent-of-origin effects, as well as additional folate-related genes, are required to more fully explore the relation between folate and congenital heart defects.

Long, Jin; Lupo, Philip J.; Goldmuntz, Elizabeth; Mitchell, Laura E.

2011-01-01

236

Synthesis, structure and bonding, optical properties of Ba?MTrQ? (M=Cu, Ag; Tr=Ga, In; Q=S, Se).  

PubMed

Four new quaternary chalcogenides, Ba4AgGaS6 (1), Ba4AgGaSe6 (2), Ba4CuInS6 (3), and Ba4AgInS6 (4), were synthesized by solid-state reactions and their structures were characterized through single-crystal X-ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6](8-) 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner-sharing MQ4 or TrQ4 tetrahedra. However, the transition metals and triels are mixed in 1, 2, and 3, but they occupy independent crystallographic sites in 4. As a result, compounds?1-3 belong to the known Ba2CoS3 (Pnma No.?62) or Ba2 MnS3 (Pnma No.?62) class, whereas 4 crystallizes in its own structural type within the monoclinic P2?/c (No.?14) space group. The structural relationship among these new phases was also studied with the aid of DFT calculations and related optical properties are presented as well. PMID:24519897

Lei, Xiao-Wu; Yang, Min; Xia, Sheng-Qing; Liu, Xiao-Cun; Pan, Ming-Yan; Li, Xin; Tao, Xu-Tang

2014-04-01

237

Effect of three novel polyamine oxa-analogues (MTR-OSPD, DIP-SPN and APPO-TFA) on the growth and proliferation of Swiss 3T3 cells  

Microsoft Academic Search

In order to investigate their biological function on cellular polyamine content, cell growth and proliferation, three novel polyamine oxa-analogues, 5-(4-methoxy-2,3,6-trimethylbenzenesulfonyl)-6-oxa-spermidine (MTR-OSPD); 6,9-dioxa-5,10-di-(2,2,5,7,8-pentamethylchroman-6-sulfonyl)spermine (DIP-SPN) and 3-aminopropyl N-(3-phthalimidopropyloxy)trifluoroacetimidate (APPO-TFA) were tested for their ability to stop or slow down the growth of Swiss 3T3 cells. Cells at 50–60% confluency were grown for 24 or 48 hr in the presence of a wide

Nuala M. Maguire; Paul Kong Thoo Lin

1996-01-01

238

Maternal Genetic Effects, Exerted by Genes Involved in Homocysteine Remethylation, Influence the Risk of Spina Bifida  

PubMed Central

There is currently considerable interest in the relationship between variation in genes that are involved in the folate-homocysteine metabolic axis and the risk of spina bifida. The evaluation of this relationship is, however, complicated by the potential involvement of both the maternal and the embryonic genotype in determination of disease risk. The present study was designed to address questions regarding both maternal and embryonic genetic risk factors for spina bifida by use of the two-step transmission/disequilibrium test. Analysis of data on variants of two genes involved in homocysteine remethylation/methionine biosynthesis—methionine synthase (MTR) A2756G and methionine synthase reductase (MTRR) A66G—provided evidence that both variants influence the risk of spina bifida via the maternal rather than the embryonic genotype. For both variants, the risk of having a child with spina bifida appears to increase with the number of high-risk alleles in the maternal genotype: MTR (R1=2.16, 95% CI 0.92–5.06; R2=6.58, 95% CI 0.87–49.67) and MTRR (R1=2.05, 95% CI 1.05–3.99; R2=3.15, 95% CI 0.92–10.85). These findings highlight the importance of considering both the maternal and embryonic genotype when evaluating putative spina bifida susceptibility loci.

Doolin, Marie-Therese; Barbaux, Sandrine; McDonnell, Maeve; Hoess, Katy; Whitehead, Alexander S.; Mitchell, Laura E.

2002-01-01

239

Air1 Zinc Knuckles 4 and 5 and a Conserved IWRXY Motif Are Critical for the Function and Integrity of the Trf4/5-Air1/2-Mtr4 Polyadenylation (TRAMP) RNA Quality Control Complex*  

PubMed Central

In Saccharomyces cerevisiae, non-coding RNAs, including cryptic unstable transcripts (CUTs), are subject to degradation by the exosome. The Trf4/5-Air1/2-Mtr4 polyadenylation (TRAMP) complex in S. cerevisiae is a nuclear exosome cofactor that recruits the exosome to degrade RNAs. Trf4/5 are poly(A) polymerases, Mtr4 is an RNA helicase, and Air1/2 are putative RNA-binding proteins that contain five CCHC zinc knuckles (ZnKs). One central question is how the TRAMP complex, especially the Air1/2 protein, recognizes its RNA substrates. To characterize the function of the Air1/2 protein, we used random mutagenesis of the AIR1/2 gene to identify residues critical for Air protein function. We identified air1-C178R and air2-C167R alleles encoding air1/2 mutant proteins with a substitution in the second cysteine of ZnK5. Mutagenesis of the second cysteine in AIR1/2 ZnK1–5 reveals that Air1/2 ZnK4 and -5 are critical for Air protein function in vivo. In addition, we find that the level of CUT, NEL025c, in air1 ZnK1–5 mutants is stabilized, particularly in air1 ZnK4, suggesting a role for Air1 ZnK4 in the degradation of CUTs. We also find that Air1/2 ZnK4 and -5 are critical for Trf4 interaction and that the Air1-Trf4 interaction and Air1 level are critical for TRAMP complex integrity. We identify a conserved IWRXY motif in the Air1 ZnK4-5 linker that is important for Trf4 interaction. We also find that hZCCHC7, a putative human orthologue of Air1 that contains the IWRXY motif, localizes to the nucleolus in human cells and interacts with both mammalian Trf4 orthologues, PAPD5 and PAPD7 (PAP-associated domain containing 5 and 7), suggesting that hZCCHC7 is the Air component of a human TRAMP complex.

Fasken, Milo B.; Leung, Sara W.; Banerjee, Ayan; Kodani, Maja O.; Chavez, Ramiro; Bowman, Elizabeth A.; Purohit, Meghan K.; Rubinson, Max E.; Rubinson, Emily H.; Corbett, Anita H.

2011-01-01

240

Variants of Folate Metabolism Genes and Risk of Left-Sided Cardiac Defects  

PubMed Central

Background Congenital heart defects (CHD) are the most common, serious group of birth defects. Although relatively little is known about the causes of these conditions and there are no established prevention strategies, evidence suggests that the risk of CHD may be related to maternal folate status as well as genetic variants in folate-related genes. Efforts to establish the relationships between these factors and CHD risk have, however, been hampered by a number of factors, including small study sample sizes and phenotypic heterogeneity. Methods The present study examined the relationship between nine genetic variants in eight folate-related genes and a relatively homogeneous group of left-sided cardiac defects in a cohort of 386 case-parent triads. Log-linear analyses were used to assess both maternal and inherited genetic effects. Results Analyses of the study data provided marginal evidence that the maternal MTR A2756G (unadjusted p=0.01) and the inherited BHMT G742A genotypes (unadjusted p=0.06) influence the risk of this subset of CHD. However, neither association achieved significance when the false-discovery rate was controlled at 0.05. Conclusions These results, which are based on the largest study sample and most comprehensive assessment of the relationship between left-sided cardiac defects and folate-related genes reported to date, provide little evidence that this subset of CHD is folate-related. However, even larger studies and more comprehensive evaluations of the folate pathway genes are required to fully explore the relationship between folate and left-sided cardiac defects.

Mitchell, Laura E.; Long, Jin; Garbarini, Jennifer; Paluru, Prasuna; Goldmuntz, Elizabeth

2010-01-01

241

Cotranscriptional recruitment of RNA exosome cofactors Rrp47p and Mpp6p and two distinct Trf-Air-Mtr4 polyadenylation (TRAMP) complexes assists the exonuclease Rrp6p in the targeting and degradation of an aberrant messenger ribonucleoprotein particle (mRNP) in yeast.  

PubMed

The cotranscriptional mRNA processing and packaging reactions that lead to the formation of export-competent messenger ribonucleoprotein particles (mRNPs) are under the surveillance of quality control steps. Aberrant mRNPs resulting from faulty events are retained in the nucleus with ensuing elimination of their mRNA component. The molecular mechanisms by which the surveillance system recognizes defective mRNPs and stimulates their destruction by the RNA degradation machinery are still not completely elucidated. Using an experimental approach in which mRNP formation in yeast is disturbed by the action of the bacterial Rho helicase, we have shown previously that the targeting of Rho-induced aberrant mRNPs is mediated by Rrp6p, which is recruited cotranscriptionally in association with Nrd1p following Rho action. Here we investigated the specific involvement in this quality control process of different cofactors associated with the nuclear RNA degradation machinery. We show that, in addition to the main hydrolytic action of the exonuclease Rrp6p, the cofactors Rrp47p, Mpp6p as well as the Trf-Air-Mtr4 polyadenylation (TRAMP) components Trf4p, Trf5p, and Air2p contribute significantly by stimulating the degradation process upon their cotranscriptional recruitment. Trf4p and Trf5p are apparently recruited in two distinct TRAMP complexes that both contain Air2p as component. Surprisingly, Rrp47p appears to play an important role in mutual protein stabilization with Rrp6p, which highlights a close association between the two partners. Together, our results provide an integrated view of how different cofactors of the RNA degradation machinery cooperate to target and eliminate aberrant mRNPs. PMID:24047896

Stuparevic, Igor; Mosrin-Huaman, Christine; Hervouet-Coste, Nadège; Remenaric, Mateja; Rahmouni, A Rachid

2013-11-01

242

MTR benchmark static calculations with MCNP5 code  

Microsoft Academic Search

With the sustained development in computer technology, the use of more powerful computational tools becomes mandatory. The challenge today is to revisit safety features of the existing nuclear research reactors using new generation of computer tools. The objective is to verify that the safety requirements still met and when necessary to introduce some amendments coming from the new attainments. In

Anis Bousbia-Salah; Hocine Benkharfia; Nateekoool Kriangchaiporn; Alessandro Petruzzi; Francesco D’Auria; Nidal Ghazi

2008-01-01

243

The Folate Pathway and Nonsyndromic Cleft Lip and Palate  

PubMed Central

Nonsyndromic cleft lip with or without cleft palate (NSCLP) is a common birth malformation caused by genetic, environmental and gene-environment interactions. Periconceptional supplementation with folic acid, a key component in DNA synthesis and cell division, has reduced the birth prevalence of neural tube defects (NTDs) and may similarly reduce the birth prevalence of other complex birth defects including NSCLP. Past studies investigating the role of two common methylenetetrahydrofolate reductase (MTHFR) SNP polymorphisms, C677T (rs1801133) and A1298C (rs1801131), in NSCLP have produced conflicting results. Most studies of folate pathway genes have been limited in scope, as few genes/SNPs have been interrogated. In this study, we asked whether variations in a more comprehensive group of folate pathway genes were associated with NSCLP and, if so, were there detectable interactions between these genes and environmental exposures. In addition, we evaluated the data for a sex effect. Fourteen folate metabolism related genes were interrogated using eighty-nine SNPs in multiplex and simplex non-Hispanic White (NHW) (317) and Hispanic (128) NSCLP families. Evidence for a risk association between NSCLP and SNPs in nitrous oxide 3 (NOS3) and thymidylate synthetase (TYMS) was detected in the NHW group, whereas associations with methionine synthase (MTR), betaine-homocysteine methyltransferase (BHMT2), MTHFS and SLC19A1 were detected in the Hispanic group. Evidence for over-transmission of haplotypes and gene interactions in the methionine arm was detected. These results suggest that perturbations of the genes in the folate pathway may contribute to NSCLP. There was evidence for an interaction between several SNPs and maternal smoking, and for one SNP with sex of the offspring. These results provide support for other studies that suggest that high maternal homocysteine levels may contribute to NSCLP and should be further investigated.

Blanton, Susan H.; Henry, Robin R.; Yuan, Quiping; Mulliken, John B.; Stal, Samuel; Finnell, Richard H.; Hecht, Jacqueline T.

2013-01-01

244

Microstructural analysis of MTR fuel plates damaged by a coolant flow blockage  

NASA Astrophysics Data System (ADS)

In 1975, as a result of a blockage of the coolant inlet flow, two plates of a fuel element of the BR2 reactor of the Belgian Nuclear Research Centre (SCK•CEN) were partially melted. The fuel element consisted of Al-clad plates with 90% 235U enriched UAl x fuel dispersed in an Al matrix. The element had accumulated a burn up of 21% 235U before it was removed from the reactor. Recently, the damaged fuel plates were sent to the hot laboratory for detailed PIE. Microstructural changes and associated temperature markers were used to identify several stages in the progression to fuel melting. It was found that the temperature in the center of the fuel plate had increased above 900-950 °C before the reactor was scrammed. In view of the limited availability of such datasets, the results of this microstructural analysis provide valuable input in the analysis of accident scenarios for research reactors.

Leenaers, A.; Joppen, F.; Van den Berghe, S.

2009-10-01

245

Transition Response Characteristics of Heat-Assisted Magnetic Recording and Their Performance With MTR Codes  

Microsoft Academic Search

The response of a heat-assisted magnetic recording (HAMR) system is very sensitive to the laser spot position. The response is determined by transition characteristics like the center, curvature, and length. In this paper, by using the thermal Williams-Comstock model and the microtrack model, the effects of laser spot position on transition characteristics are investigated for both longitudinal and perpendicular recording

Rathnakumar Radhakrishnan; M. Fatih Erden; Ching He; Bane Vasic

2007-01-01

246

Practical MTR-FDTS (?=2) read channel for the >200 Mbit\\/sec Era  

Microsoft Academic Search

This paper presents an architecture for a fixed-delay tree search with feedback (FDTS\\/DF) channel which uses a maximum transition run-length code. The critical timing path in this new detector is comparable to that of a decision feedback detector. The forward filter consists of a first-order all-pass filter cascaded with a fourth-order Bessel filter. Timing and gain recovery are also discussed

I. Kovacs; Jason Byrne; Jack Kenney

1998-01-01

247

Health and safety plan for characterization sampling of ETR and MTR facilities  

SciTech Connect

This health and safety plan establishes the procedures and requirements that will be used to minimize health and safety risks to persons performing Engineering Test Reactor and Materials Test Reactor characterization sampling activities, as required by the Occupational Safety and Health Administration standard, 29 CFR 1910.120. It contains information about the hazards involved in performing the tasks, and the specific actions and equipment that will be used to protect persons working at the site.

Baxter, D.E.

1994-10-01

248

Sensitivity of reactivity insertion limits with respect to safety parameters in a typical MTR  

Microsoft Academic Search

The sensitivity of various safety parameters, affecting the reactivity insertion limits imposed by clad melting temperature for a typical pool type research reactor, have been investigated in this work. The analysis was done for low enriched uranium (LEU) core with scram disabled conditions. The temperature coefficients of fuel and coolant, void\\/density coefficient and ?eff were individually varied and the reactor

Rubina Nasir; Nasir M. Mirza; Sikander M. Mirza

1999-01-01

249

Structured LDPC Codes With Reversed MTR\\/ECC for Magnetic Recording Channels  

Microsoft Academic Search

We propose a system for magnetic recording channels where we use a novel structured low-density parity-check (LDPC) code, called a random interleaved array (RIA) code, combined with a reversed maximum-transition run code\\/error-correction code. Simulation results show that the RIA code provides a significantly better error-rate floor performance than the conventionally structured LDPC code when applied to perpendicular magnetic recording channels.

Toshikazu Kanaoka; Toshihiko Morita

2006-01-01

250

DTI and MTR abnormalities in schizophrenia: Analysis of white matter integrity  

Microsoft Academic Search

Diffusion tensor imaging (DTI) studies in schizophrenia demonstrate lower anisotropic diffusion within white matter due either to loss of coherence of white matter fiber tracts, to changes in the number and\\/or density of interconnecting fiber tracts, or to changes in myelination, although methodology as well as localization of such changes differ between studies. The aim of this study is to

M. Kubicki; C. F. Westin; P. G. Nestor; R. V. Mulkern; S. E. Maier; M. Niznikiewicz; E. E. Connor; J. J. Levitt; M. Frumin; R. Kikinis; F. A. Jolesz; R. W. McCarley; M. E. Shenton

2005-01-01

251

Isolation and Characterization of Saccharomyces cerevisiae mRNA Transport-defective (mtr) Mutants  

Microsoft Academic Search

To understand the mechanisms of mRNA transport in eukaryotes, we have isolated Sac- charomyces cerevisiae temperature-sensitive (ts) mu- tants which accumulate poly(A) + RNA ha the nucleus at the restrictive temperature. A total of 21 recessive mutants were isolated and classified into 16 com- plementation groups. Backcrossed mRNA transport- defective strains from each complementation group have been analyzed. A strain

Tatsuhiko Kadowaki; Shaoping Chen; Midori Hitomi; Erica Jacobs; Chino Kumagai; Shuang Liang; Roger Schneiter; David Singleton; Joanna Wisniewska; Alan M. Tartakoff

1994-01-01

252

46 CFR 11.950 - Subjects for engineer endorsements.  

Code of Federal Regulations, 2010 CFR

...950âSubjects for Engineer Endorsements Unlimited chief engineer STM MTR Unlimited 1st asst. engineer STM MTR Unlimited 2nd asst. engineer STM MTR Unlimited 3rd asst. engineer STM MTR Chief engineer limited STM...

2010-10-01

253

46 CFR 11.950 - Subjects for engineer endorsements.  

Code of Federal Regulations, 2013 CFR

...950âSubjects for Engineer Endorsements Unlimited chief engineer STM MTR Unlimited 1st asst. engineer STM MTR Unlimited 2nd asst. engineer STM MTR Unlimited 3rd asst. engineer STM MTR Chief engineer limited STM...

2013-10-01

254

33 CFR 154.1015 - Applicability.  

Code of Federal Regulations, 2013 CFR

...Applicability. (a) This subpart applies to all MTR facilities that because of their location...exclusive economic zone. (b) The following MTR facilities that handle, store, or...shorelines and are classified as substantial harm MTR facilities: (1) Fixed MTR...

2013-07-01

255

33 CFR 154.1015 - Applicability.  

Code of Federal Regulations, 2010 CFR

...Applicability. (a) This subpart applies to all MTR facilities that because of their location...exclusive economic zone. (b) The following MTR facilities that handle, store, or...shorelines and are classified as substantial harm MTR facilities: (1) Fixed MTR...

2009-07-01

256

33 CFR 154.1015 - Applicability.  

Code of Federal Regulations, 2010 CFR

...Applicability. (a) This subpart applies to all MTR facilities that because of their location...exclusive economic zone. (b) The following MTR facilities that handle, store, or...shorelines and are classified as substantial harm MTR facilities: (1) Fixed MTR...

2010-07-01

257

46 CFR 11.950 - Subjects for engineer endorsements.  

Code of Federal Regulations, 2010 CFR

...950âSubjects for Engineer Endorsements Unlimited chief engineer STM MTR Unlimited 1st asst. engineer STM MTR Unlimited 2nd asst. engineer STM MTR Unlimited 3rd asst. engineer STM MTR Chief engineer limited STM...

2009-10-01

258

Association of deep venous thrombosis with prothrombotic gene polymorphism identified in lung cancer cases.  

PubMed

Venous thrombosis is a significant cause of morbidity and mortality in patients with malignancies. We aimed to investigate the association between prothrombotic gene polymorphisms detected in lung cancer cases and deep venous thrombosis (DVT). Totally 66 patients with an established diagnosis of lung cancer, of which 33 developed DVT, were enrolled. Multiplex PCR technique and reverse hybridization strip assay were performed on DNA extracted from peripheral blood, in order to analyze prothrombin G20210A, factor V G1691A, methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, angiotensin converting enzyme (ACE), plasminogen activator inhibitor-1 (PAI-1), and glycoprotein IIIa (Gp IIIa) gene mutations. Among prothrombotic gene polymorphisms investigated in this study, the commonest ones were PAI-1 4G/5G (56% heterozygous, 39% homozygous) and ACE gene mutations (58% heterozygous, 17% homozygous). The presence of homozygous MTHFR A1298C mutation was significantly associated with DVT (P=0.020). Comparing the lung cancer patients with and without DVT, only MTHFR A1298C gene polymorphism differed significantly (P=0.040). We determined a higher rate of prothrombotic gene mutations in lung cancer patients who developed DVT. However, statistical significance was achieved only for MTHFR A1298C gene mutation. Therefore, nongenetic factors for disturbance of hemostatic metabolism should also be considered in lung cancer patients. PMID:21080081

Arslan, Sulhattin; Manduz, Sinasi; Epöztürk, Kür?at; Karahan, O?uz; Akkurt, Ibrahim

2011-04-01

259

Polymorphisms in methylenetetrahydrofolate reductase gene and risk of non-Hodgkin lymphoma in a multi-ethnic population.  

PubMed

An imbalance in folate metabolism can adversely affect DNA synthesis and methylation systems which can lead to susceptibility to non-Hodgkin lymphoma (NHL). Whether single nucleotide polymorphisms (SNPs) and their haplotypes in the methylenetetrahydrofolate reductase (MTHFR) are associated with NHL, remain inconclusive. We investigated the association between MTHFR C677T and A1298C SNPs and NHL risk in a population which is made up of Malay, Chinese and Indian ethnic subgroups. A total of 372 NHL patients and 722 controls were genotyped using the Sequenom MassARRAY platform. Our results of the pooled subjects failed to demonstrate significant association between the MTHFR C677T and A1298C SNPs with NHL and its subtypes. The results were in agreement with the previous meta-analyses. In the Indian ethnic subgroup however, single locus analysis of MTHFR A1298C appears to confer risk to NHL (Odds ratio (OR) 1.91, 95% confidence interval (95% CI) 1.22-3.00, P=0.006). The risk is almost doubled in homozygous carrier of MTHFR 1298CC (OR 4.03, 95% CI 1.56-10.43, P=0.004). Haplotype analysis revealed higher frequency of CC in the Indian NHL patients compared with controls (OR 1.86, 95% CI 1.18-2.93, P=0.007). There is lack of evidence to suggest an association between MTHFR C677T and A1298C with the risk of NHL in the Malays and Chinese. In the Indians however, the MTHFR A1298C confers risk to NHL. This study suggests ethnicity modifies the relationship between polymorphisms in the folate-metabolizing gene and NHL. PMID:24646728

Suthandiram, Sujatha; Gan, Gin Gin; Zain, Shamsul Mohd; Haerian, Batoul Sadat; Bee, Ping Chong; Lian, Lay Hoong; Chang, Kian Meng; Ong, Tee Chuan; Mohamed, Zahurin

2014-05-01

260

Methylenetetrahydrofolate Reductase Polymorphisms and Risk of Acute Lymphoblastic Leukemia-Evidence from an updated meta-analysis including 35 studies  

PubMed Central

Background 5,10-methylenetetrahydrofolate reductase (MTHFR) variants, C677T and A1298C, have been reported to be associated with decreased risk of acute lymphoblastic leukemia (ALL). However, results derived from individually underpowered studies are conflicting. We carried out an updated meta-analysis on the association between MTHFR polymorphisms and ALL risk. Methods Relevant publications were searched through PUBMED and EMBASE databases. The associations between MTHFR C677T and A1298C polymorphisms and the risk of ALL were evaluated by odds ratios (ORs). The heterogeneity and publication bias were estimated. Meta-regression analysis was performed to evaluate the potential sources of heterogeneity. Results C677T polymorphism was associated with a reduced risk of ALL (allele contrast: ORRE?=?0.91, 95% CI: 0.83-0.99). Subgroup analysis showed MTHFR C677T variant was associated with decreased susceptibility to ALL in children and Caucasians. Meta-regression showed the logOR for the association between T allele and ALL increased as sex ratio (M/F) in the case group increased (P?=?0.01). Regarding A1298C polymorphism, no significant association was observed (allele contrast: ORRE?=?1.01, 95% CI: 0.91-1.11). There was no publication bias for C677T or A1298C polymorphism. Conclusions The present meta-analysis suggests that the C677T polymorphism, not A1298C, in MTHFR gene is associated with a decreased risk of ALL, particularly among children and Caucasians subjects. Our findings suggest that the influence of the C677T polymorphism on ALL susceptibility is modified by sex ratio in cases (M/F). Since folate intake may be a possible confounding factor, including this factor in future prospective studies is warranted. Further meta-analysis studies should be at least stratified for folate levels and gender to give more powerful and informative results.

2012-01-01

261

Evidence for the Assembly of a Bacterial Tripartite Multidrug Pump with a Stoichiometry of 3:6:3*  

PubMed Central

The multiple transferable resistance (mTR) pump from Neisseria gonorrhoeae MtrCDE multidrug pump is assembled from the inner and outer membrane proteins MtrD and MtrE and the periplasmic membrane fusion protein MtrC. Previously we established that while there is a weak interaction of MtrD and MtrE, MtrC binds with relatively high affinity to both MtrD and MtrE. MtrD conferred antibiotic resistance only when it was expressed with MtrE and MtrC, suggesting that these proteins form a functional tripartite complex in which MtrC bridges MtrD and MtrE. Furthermore, we demonstrated that MtrC interacts with an intraprotomer groove on the surface of MtrE, inducing channel opening. However, a second groove is apparent at the interface of the MtrE subunits, which might also be capable of engaging MtrC. We have now established that MtrC can be cross-linked to cysteines placed in this interprotomer groove and that mutation of residues in the groove impair the ability of the pump to confer antibiotic resistance by locking MtrE in the closed channel conformation. Moreover, MtrE K390C forms an intermolecular disulfide bond with MtrC E149C locking MtrE in the open channel conformation, suggesting that a functional salt bridge forms between these residues during the transition from closed to open channel conformations. MtrC forms dimers that assemble into hexamers, and electron microscopy studies of single particles revealed that these hexamers are arranged into ring-like structures with an internal aperture sufficiently large to accommodate the MtrE trimer. Cross-linking of single cysteine mutants of MtrC to stabilize the dimer interface in the presence of MtrE, trapped an MtrC-MtrE complex with a molecular mass consistent with a stoichiometry of 3:6 (MtrE3MtrC6), suggesting that dimers of MtrC interact with MtrE, presumably by binding to the two grooves. As both MtrE and MtrD are trimeric, our studies suggest that the functional pump is assembled with a stoichiometry of 3:6:3.

Janganan, Thamarai K.; Bavro, Vassiliy N.; Zhang, Li; Matak-Vinkovic, Dijana; Barrera, Nelson P.; Venien-Bryan, Catherine; Robinson, Carol V.; Borges-Walmsley, Maria Ines; Walmsley, Adrian R.

2011-01-01

262

Program Guide for Basic Precision Machining 8754000 (IN48.052300) and Precision Machining MTR0470 (IN48.050300).  

ERIC Educational Resources Information Center

This competency-based program guide provides course content information and procedures for secondary schools, postsecondary vocational schools, and community colleges in Florida that conduct programs in basic precision machining and precision machining. The first section is on legal authority, which applies to all vocational education programs in…

University of South Florida, Tampa. Dept. of Adult and Vocational Education.

263

Dynamic calculations of the IAEA safety MTR research reactor Benchmark problem using RELAP5\\/3.2 code  

Microsoft Academic Search

Nowadays, increased attention to safety issues for nuclear research reactors has emerged as a consequence of their enlarged commercial exploitation. Almost all of the research reactors safety analyses were, so far, performed using conservative computational tools. Currently, the application of Best-Estimate methods constitutes a real necessity in order to get a more realistic vision of the system behavior, and overcome

Tewfik Hamidouche; Anis Bousbia-Salah; Martina Adorni; Franscesco D'Auria

2004-01-01

264

Potential Inherited Causes of Recurrent Prosthetic Mitral Valve Thrombosis in a Pregnant Patient Suffering from Recurrent Miscarriage  

PubMed Central

An effective anticoagulation is critical in pregnant patients with prosthetic heart valves. Inherited disorders may interfere with the coagulation cascade and may be associated with obstetrical complications as well as with prosthetic valve-derived complications. The patient in the present case had a history of recurrent prosthetic heart valve thrombosis (PHVT) despite an effective anticoagulation. She underwent a thrombolysis with low-dose prolonged infusion of tissue-type plasminogen activator for the management of her recurrrent prosthetic valve thrombosis. The genetic testing showed homozygous mutations of methylenetetrahydrofolate reductase (MTHFR) A 1298 C and heterozygous mutations of ?-fibrinogen 455 G-A. Inherited disorders such as MTHFR A 1298 C and fibrinogen 455G/A polymorphisms may be involved in the pathogenesis of recurrent PHVT and/or pregnancy loss.

Gursoy, M. Ozan; Karakoyun, Suleyman; Yesin, Mahmut; Astarcioglu, Mehmet Ali; Ozkan, Mehmet

2014-01-01

265

Association between polymorphisms in genes encoding methylenetetrahydrofolate reductase and the risk of Ménière's disease.  

PubMed

Folate metabolism is essential for cellular functioning. Despite extensive research on the roles of folate-metabolism-related gene polymorphisms in the pathophysiology of many diseases, such as cardiovascular disease, cancers, and sudden sensorineural hearing loss, little is known about their association with Ménière's disease (MD). The aim of this study was to investigate the effect of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms (C677T and A1298C) on the risk of MD in a Japanese population. We examined the C677T and A1298C (rs1801133 and rs1801131) polymorphisms in the MTHFR gene and compared them between 1946 adults (986 men and 960 women) participating in the National Institute for Longevity Sciences Longitudinal Study of Aging and 86 cases of MD. A multiple logistic regression was performed to obtain odds ratios (ORs) for the risk of MD regarding the MTHFR polymorphisms before (model 1) and after (model 2) adjustment for age and sex factors. The OR of MTHFR C677T for the risk of MD was 0.669 (95% confidence interval [CI], 0.479-0.934) in model 1 and 0.680 (95% CI, 0.484-0.954) in model 2. In contrast, the OR of MTHFR A1298C for the risk of MD was 1.503 (95% CI, 1.064-2.123) in model 1 and 1.505 (95% CI, 1.045-2.167) in model 2. Our results imply that the MTHFR C677T and A1298C polymorphisms are associated with the risk of MD. PMID:23484733

Huang, Yang; Teranishi, Masaaki; Uchida, Yasue; Nishio, Naoki; Kato, Ken; Otake, Hironao; Yoshida, Tadao; Sone, Michihiko; Sugiura, Saiko; Ando, Fujiko; Shimokata, Hiroshi; Nakashima, Tsutomu

2013-06-01

266

Association of MTHFR gene polymorphisms with breast cancer survival  

Microsoft Academic Search

BACKGROUND: Two functional single nucleotide polymorphisms (SNPs) in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, C677T and A1298C, lead to decreased enzyme activity and affect chemosensitivity of tumor cells. We investigated whether these MTHFR SNPs were associated with breast cancer survival in African-American and Caucasian women. METHODS: African-American (n = 143) and Caucasian (n = 105) women, who had incident breast cancer

Damali N Martin; Brenda J Boersma; Tiffany M Howe; Julie E Goodman; Leah E Mechanic; Stephen J Chanock; Stefan Ambs

2006-01-01

267

MTHFR Polymorphisms Involved in Vitamin B 12 Deficiency Associated with Atrophic Gastritis  

Microsoft Academic Search

Genetic polymorphisms affecting methylentetrahydrofolate reductase (MTHFR) activity may influence hematological and neurological\\u000a dysfunction in cobalamin-deficient patients. We studied the prevalence of C677T and A1298C polymorphisms by analyzing genomic\\u000a DNA in 30 cobalamin-deficient patients. No significant difference was found in 677 and 1298 genotype distribution with respect\\u000a to hematological parameters, B12 and folate levels, and neurological symptoms. The two MTHFR polymorphisms

Mariangela Palladino; Patrizia Chiusolo; Giovanni Reddiconto; Sara Marietti; Daniela De Ritis; Giuseppe Leone; Simona Sica

2009-01-01

268

5,10-Methylenetetrahydrofolate Reductase Gene Variants and Congenital Anomalies: A HuGE Review  

Microsoft Academic Search

The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism. The MTHFR gene is located on chromosome 1 (1p36.3), and two common alleles, the C677T (thermolabile) allele and the A1298C allele, have been described. The population frequency of C677T homozygosity ranges from 1% or less among Blacks from Africa and the United States to 20% or more among Italians and

Lorenzo D. Botto; Quanhe Yang

2000-01-01

269

The Association between MTHFR Gene Polymorphisms and Hepatocellular Carcinoma Risk: A Meta-Analysis  

PubMed Central

Background The association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and hepatocellular carcinoma (HCC) risk was inconsistent and underpowered. To clarify the effects of MTHFR gene polymorphisms on the risk of HCC, a meta-analysis of all available studies relating C677T and/or A1298C polymorphisms of MTHFR gene to the risk of HCC was conducted. Methods The authors searched PubMed, EMBASE, Cochrane Library, Web of Science, and Chinese Biomedical Literature database (CBM) for the period up to July 2012. Data were extracted by two independent authors and pooled odds ratio (OR) with 95% confidence interval (CI) was calculated. Metaregression and subgroup analyses were performed to identify the source of heterogeneity. Results Finally, 12 studies with 2,351 cases and 4,091 controls were included for C677T polymorphism and 6 studies with 1,333 cases and 1,878 controls were included for A1298C polymorphism. With respect to A1298C polymorphism, significantly decreased HCC risk was found in the overall population (CC vs. AA: OR?=?0.660, 95%CI 0.460–0.946, P?=?0.024; recessive model: OR?=?0.667, 95%CI?=?0.470–0.948, P?=?0.024). In subgroup analyses, significantly decreased HCC risk was found in Asian population (CC vs. AA: OR?=?0.647, 95%CI?=?0.435–0.963; P?=?0.032) and population-based studies (CC vs. AA: OR?=?0.519, 95%CI?=?0.327–0.823; P?=?0.005). With respect to C677T polymorphism, no significant association with HCC risk was demonstrated in overall and stratified analyses. Conclusions We concluded that MTHFR A1298C polymorphism may play a protective role in the carcinogenesis of HCC. Further large and well-designed studies are needed to confirm this association.

Deng, Yan; Huang, Shan; Xu, Juanjuan; Li, Haiwei; Li, Shan; Zhao, Jinmin

2013-01-01

270

Tripartite efflux pumps: energy is required for dissociation, but not assembly or opening of the outer membrane channel of the pump  

PubMed Central

The MtrCDE multidrug pump, from Neisseria gonorrhoeae, is assembled from the inner and outer membrane proteins MtrD and MtrE, which are connected by the periplasmic membrane fusion protein MtrC. Although it is clear that MtrD delivers drugs to the channel of MtrE, it remains unclear how drug delivery and channel opening are connected. We used a vancomycin sensitivity assay to test for opening of the MtrE channel. Cells expressing MtrE or MtrE-E434K were insensitive to vancomycin; but became moderately and highly sensitive to vancomycin respectively, when coexpressed with MtrC, suggesting that the MtrE channel opening requires MtrC binding and is energy-independent. Cells expressing wild-type MtrD, in an MtrCE background, were vancomycin-insensitive, but moderately sensitive in an MtrCE-E434K background. The mutation of residues involved in proton translocation inactivated MtrD and abolished drug efflux, rendered both MtrE and MtrE-E434K vancomycin-insensitive; imply that the pump–component interactions are preserved, and that the complex is stable in the absence of proton flux, thus sealing the open end of MtrE. Following the energy-dependent dissociation of the tripartite complex, the MtrE channel is able to reseal, while MtrE-E434K is unable to do so, resulting in the vancomycin-sensitive phenotype. Thus, our findings suggest that opening of the OMP via interaction with the MFP is energy-independent, while both drug export and complex dissociation require active proton flux.

Janganan, Thamarai K; Bavro, Vassiliy N; Zhang, Li; Borges-Walmsley, Maria Ines; Walmsley, Adrian R

2013-01-01

271

Novel Mechanism of High-Level, Broad-Spectrum Antibiotic Resistance Caused by a Single Base Pair Change in Neisseria gonorrhoeae.  

National Technical Information Service (NTIS)

The MtrC-MtrD-MtrE multidrug efflux pump of Neisseria gonorrhoeae confers resistance to a diverse array of antimicrobial agents by transporting these toxic compounds out of the gonococcus. Frequently in gonococcal strains, the expression of the mtrCDE ope...

D. Golparian E. A. Ohneck P. J. Johnson V. Dhulipala Y. M. Zalucki

2011-01-01

272

HWMA/RCRA Closure Plan for the TRA/MTR Warm Waste System Voluntary Consent Order SITE-TANK-005 Tank System TRA-007  

SciTech Connect

This Hazardous Waste Management Act/Resource Conservation and Recovery Act Closure Plan was developed for portions of the Test Reactor Area/Materials Test Reactor Warm Waste System located in the Materials Test Reactor Building (TRA-603) at the Reactor Technology Complex, Idaho National Laboratory Site, to meet a further milestone established under Voluntary Consent Order Action Plan SITE-TANK-005 for the Tank System TRA-007. The reactor drain tank and canal sump to be closed are included in the Test Reactor Area/Materials Test Reactor Warm Waste System. The reactor drain tank and the canal sump will be closed in accordance with the interim status requirements of the Hazardous Waste Management Act/Resource Conservation and Recovery Act as implemented by the Idaho Administrative Procedures Act 58.01.05.009 and Code of Federal Regulations 265. This closure plan presents the closure performance standards and methods for achieving those standards.

K. Winterholler

2007-01-30

273

Using reduction and inversion tools for THEMIS-MTR data: chromospheric reversals of a moving magnetic feature and an ephemeral region .  

NASA Astrophysics Data System (ADS)

New tools have been developed for THEMIS spectropolarimetric data. In this paper we present how these tools work and can be used in order to understand two interesting observed phenomena: a moving magnetic feature and an ephemeral region.

Sainz Dalda, A.; López Ariste, A.

274

Effect of coolant channel width on group constants and multiplication factor of research reactors using MTR type low enriched uranium fuel  

Microsoft Academic Search

One dimensional transport theory lattice code wims-d\\/4 and three dimensional diffusion theory code citation have been used to study the effect of fuel loading on critical cores of low enriched uranium (LEU) fuelled material testing reactors (MTRs). The fuel loading in a fuel element was varied by changing the fuel density in the fuel meat. In order to keep the

Aslam; N. Ahmad

2002-01-01

275

A model for the analysis of loss of decay heat removal during loss of coolant accident in MTR pool type research reactors  

Microsoft Academic Search

During a loss of coolant accident leading to total emptying of the reactor pool, the decay heat could be removed through air natural convection. However, under partial pool emptying the core is partially submerged and the coolant circulation inside the fuel element could no more be possible. Under such conditions, a core overheat takes place, and the thermal energy is

Anis Bousbia-salah; Brahim Meftah; Tewfik Hamidouche; El Khider Si-Ahmed

2006-01-01

276

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms.  

National Technical Information Service (NTIS)

The purpose is training in nutritional and molecular epidemiology to establish an independent investigator. The major hypothesis is that high folate intake is associated with a decreased breast cancer risk particularly among those with MTHFR, MTR, and MTR...

M. J. SHrubsole

2006-01-01

277

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms.  

National Technical Information Service (NTIS)

The purpose is training in nutritional and molecular epidemiology to establish an independent investigator. The major hypothesis is that high folate intake is associated with a decreased breast cancer risk particularly among those with MTHFR, MTR, and MTR...

M. J. Shrubsole

2005-01-01

278

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms.  

National Technical Information Service (NTIS)

The purpose is training in nutritional and molecular epidemiology to establish an independent investigator. The major hypothesis is that high folate intake is associated with a decreased breast cancer risk particularly among those with MTHFR, MTR, and MTR...

M. J. Shrubsole

2004-01-01

279

Pathophysiologic and electrophysiologic mechanisms of myofascial trigger points  

Microsoft Academic Search

Objective: To review recent clinical and basic science studies on myofascial trigger points (MTrPs) to facilitate a better understanding of the mechanism of an MTrP.Data Sources: English literature in the last 15 years regarding scientific investigations on MTrPs in either humans or animals.Study Selection: Research works, especially electrophysiologic studies, related to the pathophysiology of MTrP.Data Synthesis: (1) Studies on an

Chang-Zern Hong; David G. Simons

1998-01-01

280

Myofascial trigger points: pathophysiology and correlation with acupuncture points  

Microsoft Academic Search

SummaryA review is made of recent studies on myofascial trigger points (MTrP) and their mechanism is discussed. Clinical and basic science studies have shown that there are multiple MTrP loci in a MTrP region. A MTrP locus contains a sensory component (sensitive locus) and a motor component (active locus). A sensitive locus is a point from which tenderness or pain,

Chang-Zern Hong

2000-01-01

281

Understanding effective treatments of myofascial trigger points  

Microsoft Academic Search

This article considers specific treatment approaches and the role of etiological mechanisms in terms of clinical feature characteristics of MTrPs: increased muscle tension, pain and tenderness, painful stretch range of motion, initiating causes of MTrPs. Final sections note additional treatments that are currently used, and summarize the etiological and clinical distinctions between MTrPs and fibromyalgia.

David G. Simons

2002-01-01

282

33 CFR 154.1017 - Response plan submission requirements.  

Code of Federal Regulations, 2010 CFR

...requirements. (a) The owner or operator of an MTR facility identified only in § 154...appropriate. This applies to: (1) A mobile MTR facility used or intended to be used to...250 barrels or more; and (2) A fixed MTR facility specifically designated as a...

2009-07-01

283

33 CFR 154.1060 - Submission and approval procedures.  

Code of Federal Regulations, 2013 CFR

...this part, as appropriate. (c) For an MTR facility that is located in the inland...prior to any final approval. (d) For an MTR facility identified in § 154.1015...revisions to the response plan. (f) For an MTR facility identified in §...

2013-07-01

284

33 CFR 154.1016 - Facility classification by COTP.  

Code of Federal Regulations, 2013 CFR

...upgrade the classification of: (1) An MTR facility not specified in § 154.1015...harm to the environment; or (2) An MTR facility specified in § 154.1015(b...downgrade, the classification of: (1) An MTR facility specified in §...

2013-07-01

285

Serial magnetization transfer imaging in acute optic neuritis  

Microsoft Academic Search

Summary In serial studies of multiple sclerosis lesions, reduc- tions in magnetization transfer ratio (MTR) are thought to be due to demyelination and axonal loss, with later rises due to remyelination. This study fol- lowed serial changes in MTR in acute optic neuritis in combination with clinical and electrophysiological measurements to determine if the MTR changes over time mirror the

S. J. Hickman; A. T. Toosy; S. J. Jones; D. R. Altmann; K. A. Miszkiel; D. G. MacManus; G. J. Barker; G. T. Plant; A. J. Thompson; D. H. Miller

2004-01-01

286

33 CFR 154.1016 - Facility classification by COTP.  

Code of Federal Regulations, 2010 CFR

...upgrade the classification of: (1) An MTR facility not specified in § 154.1015...harm to the environment; or (2) An MTR facility specified in § 154.1015(b...downgrade, the classification of: (1) An MTR facility specified in §...

2009-07-01

287

33 CFR 154.1016 - Facility classification by COTP.  

Code of Federal Regulations, 2010 CFR

...upgrade the classification of: (1) An MTR facility not specified in § 154.1015...harm to the environment; or (2) An MTR facility specified in § 154.1015(b...downgrade, the classification of: (1) An MTR facility specified in §...

2010-07-01

288

33 CFR 154.1017 - Response plan submission requirements.  

Code of Federal Regulations, 2013 CFR

...requirements. (a) The owner or operator of an MTR facility identified only in § 154...appropriate. This applies to: (1) A mobile MTR facility used or intended to be used to...250 barrels or more; and (2) A fixed MTR facility specifically designated as a...

2013-07-01

289

33 CFR 154.1017 - Response plan submission requirements.  

Code of Federal Regulations, 2010 CFR

...requirements. (a) The owner or operator of an MTR facility identified only in § 154...appropriate. This applies to: (1) A mobile MTR facility used or intended to be used to...250 barrels or more; and (2) A fixed MTR facility specifically designated as a...

2010-07-01

290

The association of idiopathic recurrent early pregnancy loss with polymorphisms in folic acid metabolism-related genes.  

PubMed

The aim of this study was to investigate the association between polymorphisms in folic acid metabolism-related genes and idiopathic recurrent early pregnancy loss (REPL). A prospective case-control study was performed on a cohort of 82 REPL patients and 166 healthy controls. Genotyping of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C was assessed by applying polymerase chain reaction for amplification followed by DNA sequencing, for methionine synthase reductase A66G, solute carrier family 19, member 1 (SLC19A1) G80A and C696T, and genotyping was done by utilizing the Sequenom MassARRAY system. The results revealed a significant association between MTHFR A1298C polymorphism and idiopathic REPL. Haplotype analysis indicated that the MTHFR 677C-MTHFR 1298C allele combination was associated with REPL (P < 0.001). The MTHFR 677C-MTHFR 1298A and SLC19A1 80G-SLC19A1 696C allele combinations had lower frequencies in patients with REPL, but with P > 0.05 (P = 0.093 and P = 0.084, respectively). PMID:24728915

Cao, Yunlei; Zhang, Zhaofeng; Zheng, Yanmin; Yuan, Wei; Wang, Jian; Liang, Hong; Chen, Jianping; Du, Jing; Shen, Yueping

2014-05-01

291

Methylenetetrahydrofolate reductase gene haplotypes affect toxicity during maintenance therapy for childhood acute lymphoblastic leukemia in Japanese patients.  

PubMed

Abstract The aim of this study was to investigate the influence of daily 6-mercaptopurine (6-MP) and low-dose weekly methotrexate (MTX) combination treatment and methylenetetrahydrofolate reductase (MTHFR) haplotypes on toxicity during maintenance therapy in Japanese childhood acute lymphoblastic leukemia (ALL). We retrospectively analyzed the MTHFR C677T and A1298C polymorphisms and influence of haplotypes on toxicity in 73 patients. Patients with the MTHFR 677TT and 677CT + 1298AC were associated with severe liver toxicity (p = 0.014, odds ratio [OR] = 3.82, 95% confidence interval [CI] = 1.27-11.46) and more rapid onset of liver toxicity (p = 0.010). Patients with MTHFR 677TT and 677CT + 1298AC were associated with lower frequency of 6-MP and MTX dose reduction due to leukopenia (p < 0.05). No difference was observed in average drug doses in the MTHFR genotypes. In conclusion, the MTHFR C677T and A1298C haplotypes might be useful for monitoring adverse effects in childhood ALL maintenance therapy in Japanese patients. PMID:23865834

Tanaka, Yoichi; Manabe, Atsushi; Nakadate, Hisaya; Kondoh, Kensuke; Nakamura, Kozue; Koh, Katsuyoshi; Kikuchi, Akira; Komiyama, Takako

2014-05-01

292

Aberrant DNA methylation of the P16, MGMT, and hMLH1 genes in combination with the methylenetetrahydrofolate reductase C677T genetic polymorphism and folate intake in gastric cancer.  

PubMed

Epidemiological studies have indicated that folate metabolism is correlated with increased risk of gastric cancer. Since methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism, in this study, we examined whether polymorphisms and haplotypes of MTHFR are correlated with the risk of gastric cancer. The polymorphisms MTHFR C677T and MTHFR A1298C were genotyped by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis in 285 patients and 570 healthy controls. Association analyses based on binary logistic regression were conducted to determine the odds ratio (OR) and its 95% confidence interval (95%CI) for each genotype. The MTHFR 677TT genotype was significantly related with a reduced risk of gastric cancer (OR = 0.60, 95%CI = 0.39-0.92) compared to the CC genotype. Similarly, the MTHFR 1298CC genotype was significantly associated with a decreased risk of cancer (OR = 0.52, 95%CI = 0.32- 0.81). Haplotype analysis showed that the TC haplotype was associated with a reduced risk of gastric cancer compared to the most common haplotype, CA (OR = 0.28, 95%CI = 0.12-0.60). Our results suggest that the MTHFR C677T and MTHFR A1298C polymorphisms are related to gastric cancer susceptibility in the Chinese population. PMID:24737431

Lin, J; Zeng, R M; Li, R N; Cao, W H

2014-01-01

293

Investigation of Homocysteine-Pathway-Related Variants in Essential Hypertension  

PubMed Central

Hyperhomocysteinemia (hHcy) has been associated with an increased risk of cardiovascular disease and stroke. Essential hypertension (EH), a polygenic condition, has also been associated with increased risk of cardiovascular related disorders. To investigate the role of the homocysteine (Hcy) metabolism pathway in hypertension we conducted a case-control association study of Hcy pathway gene variants in a cohort of Caucasian hypertensives and age- and sex-matched normotensives. We genotyped two polymorphisms in the methylenetetrahydrofolate reductase gene (MTHFR C677T and MTHFR A1298C), one polymorphism in the methionine synthase reductase gene (MTRR A66G), and one polymorphism in the methylenetetrahydrofolate dehydrogenase 1 gene (MTHFD1 G1958A) and assessed their association with hypertension using chi-square analysis. We also performed a multifactor dimensionality reduction (MDR) analysis to investigate any potential epistatic interactions among the four polymorphisms and EH. None of the four polymorphisms was significantly associated with EH and although we found a moderate synergistic interaction between MTHFR A1298C and MTRR A66G, the association of the interaction model with EH was not statistically significant (P = 0.2367). Our findings therefore suggest no individual or interactive association between four prominent Hcy pathway markers and EH.

Fowdar, Javed Y.; Lason, Marta V.; Szvetko, Attila L.; Lea, Rodney A.; Griffiths, Lyn R.

2012-01-01

294

Etiopathogenesis of Sheehan's Syndrome: Roles of Coagulation Factors and TNF-Alpha  

PubMed Central

Sheehan's Syndrome (SS) is defined as pituitary hormone deficiency due to ischemic infarction of the pituitary gland as a result of massive postpartum uterine hemorrhage. Herein, we aimed to investigate the roles of Factor II (G20210A), Factor V (G1691A), MTHFR (C677T and A1298C), PAI-1 4G/5G, and TNF-? (?308??G > A) gene polymorphisms in the etiopathogenesis of SS. Venous blood samples were obtained from 53 cases with SS and 43 healthy women. Standard methods were used to extract the genomic DNAs. Factor II (G20210A), Factor V (G1691A), and MTHFR (C677T and A1298C) polymorphisms were identified by real-time PCR. PAI-1 4G/5G and TNF-? (?308??G > A) gene polymorphisms were detected with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. According to statistical analysis, none of the polymorphisms were found to be significantly higher in the SS group compared to the control group. Hence, we suggest that genetic factors other than Factor II, Factor V, MTHFR, PAI-1, and TNF-? gene polymorphisms should be researched in the etiopathogenesis of SS.

Bayram, Fahri; Tascioglu, Nazife; Simsek, Yasin; Dundar, Munis

2014-01-01

295

Gender-specific association of methylenetetrahydrofolate reductase gene polymorphisms with sporadic amyotrophic lateral sclerosis.  

PubMed

Studies have revealed that elevated homocysteine levels can cause damage to motor neurons through multiple neurotoxic mechanisms, thus leading to the pathogenesis of amyotrophic lateral sclerosis (ALS). One way by which homocysteine levels are increased in the body is the consequence of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms. Therefore, to address this question, we studied the MTHFR C677T and A1298C polymorphisms in 437 sporadic ALS (SALS) and 439 healthy controls to learn whether they were associated with SALS. The overall SALS were not associated with MTHFR C677T and A1298C polymorphisms (?(2)=1.378; p=0.502; ?(2)=1.304; p=0.521, respectively). However, when we stratified results in terms of gender, we found that the MTHFR C677T polymorphism (?(2)=6.376; p=0.041), T677T genotype (?(2)=5.508; p=0.019; odds ratio [OR]=2.561; 95% confidence interval [CI]=1.142-5.744), C677C/A1298A (?(2)=5.216; p=0.022; OR=0.424, 95% CI=0.199-0.900), and T677T/A1298A (?(2)=6.639; p=0.010; OR=2.900; 95% CI=1.252-6.717) compound genotypes were associated with SALS in female patients only. Moreover, stratification of SALS according to the onset of disease indicated that there was no association between MTHFR C677T (?(2)=1.565; p=0.457; A1298C ?(2)=3.461; p=0.177) polymorphisms and overall spinal onset SALS. Further stratification analysis according to gender revealed that there was a remarkable association between MTHFR C677T (?(2)=9.728, p=0.008), T677T genotype (?(2)=7.820; p=0.005; OR=3.126; 95% CI=1.361-7.178) and T allele (?(2)=5.000; p=0.025; OR=1.711; 95% CI=1.067-2.745), and T677T/A1298A compound genotype (?(2)=9.108; p=0.003; OR=3.540; 95% CI=1.494-8.387) and spinal onset female SALS only. Likewise, there was also association between MTHFR A1298C polymorphism (?(2)=5.946; p=0.051) and the C1298C genotype (?(2)=5.282; p=0.022; OR=2.524; 95% CI=1.125-5.658), and the C677T/C1298C compound genotype (?(2)=7.155; p=0.007; OR=1.045; 95% CI=0.983-1.112) and bulbar onset SALS only in women. In conclusion, the evidence we provide here clearly shows that MTHFR C677T and A1298C polymorphisms are genetic risk factors for SALS in women in a gender-specific manner whether they are of spinal or bulbar onset. PMID:22385294

Sazci, Ali; Ozel, Mavi Deniz; Emel, Ergul; Idrisoglu, Halil Atilla

2012-07-01

296

Characterization of Protein-Protein Interactions Involved in Iron Reduction by Shewanella oneidensis MR1  

Microsoft Academic Search

The interaction of proteins implicated in dissimilatory metal reduction by Shewanella oneidensis MR-1 (outer membrane (OM) proteins OmcA, MtrB, and MtrC; OM-associated protein MtrA; periplasmic protein CctA; and cytoplasmic membrane protein CymA) were characterized by protein purification, analytical ultracentrif- ugation, and cross-linking methods. Five of these proteins are heme proteins, OmcA (83 kDa), MtrC (75 kDa), MtrA (32 kDa), CctA

Daniel E. Ross; Shane S. Ruebush; Susan L. Brantley; Robert S. Hartshorne; Thomas A. Clarke; David J. Richardson; Ming Tien

2007-01-01

297

Hypermethylated cap 4 maximizes Trypanosoma brucei translation  

PubMed Central

Summary Through trans-splicing of a 39-nt Spliced Leader (SL) onto each protein-coding transcript, mature kinetoplastid mRNA acquire a hypermethylated 5?-cap structure, but its function has been unclear. Gene deletions for three Trypanosoma brucei cap 2?-O-ribose methyltransferases, TbMTr1, TbMTr2, and TbMTr3, reveal distinct roles for four 2?-O-methylated nucleotides. Elimination of individual gene pairs yields viable cells, however attempts at double knockouts resulted in the generation of a TbMTr2?/?/TbMTr3?/? cell line only. Absence of both kinetoplastid-specific enzymes in TbMTr2?/?/TbMTr3?/? lines yielded substrate SL RNA and mRNA with cap 1. TbMTr1?/? translation is comparable to wildtype, while cap 3 and cap 4 loss reduced translation rates, exacerbated by the additional loss of cap 2. TbMTr1?/? and TbMTr2?/?/TbMTr3?/? lines grow to lower densities under normal culture conditions relative to wildtype cells, with growth rate differences apparent under low serum conditions. Cell viability may not tolerate delays at both the nucleolar Sm-independent and nucleoplasmic Sm-dependent stages of SL RNA maturation combined with reduced rates of translation. A minimal level of mRNA cap ribose methylation is essential for trypanosome viability, providing the first functional role for the cap 4.

Zamudio, Jesse R.; Mittra, Bidyottam; Campbell, David A.; Sturm, Nancy R.

2010-01-01

298

Myofascial trigger points and innervation zone locations in upper trapezius muscles  

PubMed Central

Background Myofascial trigger points (MTrPs) are hyperirritable spots located in taut bands of muscle fibres. Electrophysiological studies indicate that abnormal electrical activity is detectable near MTrPs. This phenomenon has been described as endplate noise and it has been purported to be associated MTrP pathophysiology. Thus, it is suggested that MTrPs will be overlap the innervation zone (IZ). The purpose of this work was to describe the location of MTrPs and the IZ in the right upper trapezius. Methods We screened 71 individuals and eventually enrolled 24 subjects with neck pain and active MTrPs and 24 neck pain-free subjects with latent MTrPs. Surface electromyography (sEMG) signals were detected using an electrode matrix during isometric contraction of the upper trapezius. A physiotherapist subsequently examined the subject’s trapezius to confirm the presence of MTrPs and establish their location. IZ locations were identified by visual analysis of sEMG signals. IZ and MTrPs locations were described using an anatomical coordinate system (ACS), with the skin area covered by the matrix divided into four quadrants. Results No significant difference was observed between active and latent MTrPs locations (P = 0.6). Forty-five MTrPs were in the third quadrant of the ACS, and 3 were included in second quadrant. IZs were located approximately midway between the seventh cervical vertebrae and the acromial angle in a limited area in the second and third quadrants. The mean distance between MTrP and IZ was 10.4 ± 5.8 mm. Conclusions According to the acquired results, we conclude that IZ and MTrPs are located in well-defined areas in upper trapezius muscle. Moreover, MTrPs in upper trapezius are proximally located to the IZ but not overlapped.

2013-01-01

299

Structure of Arabidopsis thaliana 5-methylthioribose Kinase Reveals a More Occluded Active Site Than its Bacterial Homolog  

SciTech Connect

Metabolic variations exist between the methionine salvage pathway of humans and a number of plants and microbial pathogens. 5-Methylthioribose (MTR) kinase is a key enzyme required for methionine salvage in plants and many bacteria. The absence of a mammalian homolog suggests that MTR kinase is a good target for the design of specific herbicides or antibiotics. The structure of Arabidopsis thaliana MTR kinase co-crystallized with ATP?S and MTR has been determined at 1.9 Angstroms resolution. The structure is similar to B. subtilis MTR kinase and has the same protein kinase fold observed in other evolutionarily related protein kinase-like phosphotransferases. The active site is comparable between the two enzymes with the DXE-motif coordinating the nucleotide-Mg, the D238 of the HGD catalytic loop polarizing the MTR O1 oxygen, and the RR-motif interacting with the substrate MTR. Unlike its bacterial homolog, however, the Gly-rich loop (G-loop) of A. thaliana MTR kinase has an extended conformation, which shields most of the active site from solvent, a feature that resembles eukaryotic protein kinases more than the bacterial enzyme. The G- and W-loops of A. thaliana and B. subtilis MTR kinase adopt different conformations despite high sequence similarity. The ATP?S analog was hydrolyzed during the co-crystallization procedure, resulting in ADP in the active site. This suggests that the A. thaliana enzyme, like its bacterial homolog, may have significant ATPase activity in the absence of MTR. The structure of A. thaliana MTR kinase provides a template for structure-based design of agrochemicals, particularly herbicides whose effectiveness could be regulated by nutrient levels. Features of the MTR binding site offer an opportunity for a simple organic salt of an MTR analog to specifically inhibit MTR kinase.

Ku,S.; Cornell, K.; Howell, P.

2007-01-01

300

TRA Closure Plan REV 0-9-20-06 HWMA/RCRA Closure Plan for the TRA/MTR Warm Waste System Voluntary Consent Order SITE-TANK-005 Tank System TRA-007  

SciTech Connect

This Hazardous Waste Management Act/Resource Conservation and Recovery Act closure plan was developed for portions of the Test Reactor Area/Materials Test Reactor Warm Waste System located in the Materials Test Reactor Building (TRA-603) at the Reactor Technology Complex, Idaho National Laboratory Site, to meet a further milestone established under Voluntary Consent Order Action Plan SITE-TANK-005 for Tank System TRA-007. The reactor drain tank and canal sump to be closed are included in the Test Reactor Area/Materials Test Reactor Warm Waste System. The reactor drain tank and the canal sump were characterized as having managed hazardous waste. The reactor drain tank and canal sump will be closed in accordance with the interim status requirements of the Hazardous Waste Management Act/Resource Conservation and Recovery Act as implemented by the Idaho Administrative Procedures Act 58.01.05.009 and 40 Code of Federal Regulations 265. This closure plan presents the closure performance standards and methods for achieving those standards.

Winterholler, K.

2007-01-31

301

Novel Applications of Ultrasound Technology to Visualize and Characterize Myofascial Trigger Points and Surrounding Soft Tissue  

PubMed Central

Objective Apply ultrasound (US) imaging techniques to better describe the characteristics of myofascial trigger points (MTrPs) and the immediately adjacent soft tissue. Design Descriptive (exploratory) study. Setting Biomedical research center. Participants 9 subjects meeting Travell and Simons’s criteria for MTrPs in a taut band in the upper trapezius. Interventions (None) Main Outcome Measures MTrPs were evaluated by 1) physical examination, 2) pressure algometry, and 3) three types of ultrasound imaging including grayscale (2D US), vibration sonoelastography (VSE), and Doppler. Methods Four sites in each patient were labeled based on physical examination as either active MTrP (spontaneously-painful, A-MTrP), latent MTrP (non-painful, L-MTrP), or normal myofascial tissue. US examination was performed on each subject by a team blinded to the physical findings. A 12-5 MHz US transducer was used. VSE was performed by color Doppler variance imaging while simultaneously inducing vibrations (~92Hz) with a handheld massage vibrator. Each site was assigned a tissue imaging score (TIS) as follows: 0 = uniform echogenicity and stiffness; 1 = focal hypoechoic region with stiff nodule; 2 = multiple hypoechoic regions with stiff nodules. Blood flow in the neighborhood of MTrPs was assessed using Doppler imaging. Each site was assigned a blood flow waveform score (BFS) as follows: 0 = normal arterial flow in muscle; 1 = elevated diastolic flow; 2 = high-resistance flow waveform with retrograde diastolic flow. Results MTrPs appeared as focal, hypoechoic regions on 2D US, indicating local changes in tissue echogenicity, and as focal regions of reduced vibration amplitude on VSE, indicating a localized stiff nodule. MTrPs were elliptical in shape, with a size of 0.16 ± 0.11 cm2. There were no significant differences in size between A-MTrPs and L-MTrPs. Sites containing MTrPs were more likely to have higher TIS compared to normal myofascial tissue (p<0.002). Small arteries (or enlarged arterioles) near A-MTrPs showed retrograde flow in diastole indicating a highly resistive vascular bed. A-MTrP sites were more likely to have higher BFS compared to L-MTrPs (p<0.021). Conclusions Preliminary findings show that, under the conditions of this investigation, US imaging techniques can be used to distinguish myofascial tissue containing MTrPs from normal myofascial tissue (lacking trigger points). Ultrasound enables visualization and some characterization of MTrPs and adjacent soft tissue.

Sikdar, Siddhartha; Shah, Jay P.; Gebreab, Tadesse; Yen, Ru-Huey; Gilliams, Elizabeth; Danoff, Jerome; Gerber, Lynn H.

2009-01-01

302

Rapid electron exchange between surface-exposed bacterial cytochromes and Fe(III) minerals  

PubMed Central

The mineral-respiring bacterium Shewanella oneidensis uses a protein complex, MtrCAB, composed of two decaheme cytochromes, MtrC and MtrA, brought together inside a transmembrane porin, MtrB, to transport electrons across the outer membrane to a variety of mineral-based electron acceptors. A proteoliposome system containing a pool of internalized electron carriers was used to investigate how the topology of the MtrCAB complex relates to its ability to transport electrons across a lipid bilayer to externally located Fe(III) oxides. With MtrA facing the interior and MtrC exposed on the outer surface of the phospholipid bilayer, the established in vivo orientation, electron transfer from the interior electron carrier pool through MtrCAB to solid-phase Fe(III) oxides was demonstrated. The rates were 103 times higher than those reported for reduction of goethite, hematite, and lepidocrocite by S. oneidensis, and the order of the reaction rates was consistent with those observed in S. oneidensis cultures. In contrast, established rates for single turnover reactions between purified MtrC and Fe(III) oxides were 103 times lower. By providing a continuous flow of electrons, the proteoliposome experiments demonstrate that conduction through MtrCAB directly to Fe(III) oxides is sufficient to support in vivo, anaerobic, solid-phase iron respiration.

White, Gaye F.; Shi, Zhi; Shi, Liang; Wang, Zheming; Dohnalkova, Alice C.; Marshall, Matthew J.; Fredrickson, James K.; Zachara, John M.; Butt, Julea N.; Richardson, David J.; Clarke, Thomas A.

2013-01-01

303

MTHFR genetic polymorphisms may contribute to the risk of chronic myelogenous leukemia in adults: a meta-analysis of 12 genetic association studies.  

PubMed

Chronic myelogenous leukemia (CML) is a complex disease with a genetic basis. The genetic association studies (GASs) that have investigated the association between adult CML and 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms have produced contradictory and inconclusive results. The aim of this meta-analysis is to provide a relatively comprehensive assessment of the association of these polymorphisms with adult CML risk. A literature search for eligible GAS published before September 15, 2013 was conducted in PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases. Pooled odds ratios (ORs) with their corresponding 95% confidence intervals (95% CIs) were used to evaluate the strength of the association under a fixed or random effect model according to heterogeneity test results. All analyses were performed using the Stata software, version 12.0. Twelve case-control studies were included in this meta-analysis with a total of 932 CML patients and 3,465 healthy controls. For MTHFR C677T (dbSNP: rs1801133, C>T), though the pooled ORs were not significant in the overall population, all the ORs greater than 1 suggested an increased risk of CML for carriers of the risk allele. However, stratified analysis based on genotyping method revealed a significant association in the PCR-restriction fragment length polymorphism (RFLP) subgroup, possibly as a result of heterogeneity. For MTHFR A1298C (dbSNP: rs1801131, A>C), the combined results showed that carriers of the C allele may be associated with a decreased risk of adult CML. Stratified analysis showed that the magnitude of this effect was especially significant among Asians, indicating ethnicity differences in adult CML susceptibility. This meta-analysis shows that the C allele of MTHFR A1298C may be associated with a decreased risk in adult CML, especially among Asians, while MTHFR C677T may not be associated with adult CML risk. However, the development of adult CML may be the result of gene-gene and gene-environment interactions, which should be considered in future individual GAS and subsequent meta-analyses. PMID:24379141

Li, Bin; Zhang, Jian; Wang, Lei; Li, Yan; Jin, Juping; Ai, Limei; Li, Chong; Li, Zhe; Mao, Shudan

2014-05-01

304

Molecular Underpinnings of Fe(III) Oxide Reduction by Shewanella Oneidensis MR-1.  

PubMed

In the absence of O(2) and other electron acceptors, the Gram-negative bacterium Shewanella oneidensis MR-1 can use ferric [Fe(III)] (oxy)(hydr)oxide minerals as the terminal electron acceptors for anaerobic respiration. At circumneutral pH and in the absence of strong complexing ligands, Fe(III) oxides are relatively insoluble and thus are external to the bacterial cells. S. oneidensis MR-1 and related strains of metal-reducing Shewanella have evolved machinery (i.e., metal-reducing or Mtr pathway) for transferring electrons from the inner-membrane, through the periplasm and across the outer-membrane to the surface of extracellular Fe(III) oxides. The protein components identified to date for the Mtr pathway include CymA, MtrA, MtrB, MtrC, and OmcA. CymA is an inner-membrane tetraheme c-type cytochrome (c-Cyt) that belongs to the NapC/NrfH family of quinol dehydrogenases. It is proposed that CymA oxidizes the quinol in the inner-membrane and transfers the released electrons to MtrA either directly or indirectly through other periplasmic proteins. A decaheme c-Cyt, MtrA is thought to be embedded in the trans outer-membrane and porin-like protein MtrB. Together, MtrAB deliver the electrons through the outer-membrane to the MtrC and OmcA on the outmost bacterial surface. MtrC and OmcA are the outer-membrane decaheme c-Cyts that are translocated across the outer-membrane by the bacterial type II secretion system. Functioning as terminal reductases, MtrC and OmcA can bind the surface of Fe(III) oxides and transfer electrons directly to these minerals via their solvent-exposed hemes. To increase their reaction rates, MtrC and OmcA can use the flavins secreted by S. oneidensis MR-1 cells as diffusible co-factors for reduction of Fe(III) oxides. Because of their extracellular location and broad redox potentials, MtrC and OmcA can also serve as the terminal reductases for soluble forms of Fe(III). In addition to Fe(III) oxides, Mtr pathway is also involved in reduction of manganese oxides and other metals. Although our understanding of the Mtr pathway is still far from complete, it is the best characterized microbial pathway used for extracellular electron exchange. Characterizations of the Mtr pathway have made significant contributions to the molecular understanding of microbial reduction of Fe(III) oxides. PMID:22363328

Shi, Liang; Rosso, Kevin M; Clarke, Tomas A; Richardson, David J; Zachara, John M; Fredrickson, James K

2012-01-01

305

Management of myofascial trigger point pain  

Microsoft Academic Search

SummarySuccessful management of myofascial trigger point (MTrP) pain depends on the practitioner finding all of the MTrPs from which the pain is emanating, and then deactivating them by one of several currently used methods. These include deeply applied procedures, such as an injection of a local anaesthetic into MTrPs and deep dry needling (DDN), and superficially applied ones, including an

Peter Baldry

2002-01-01

306

Treatment of myofascial trigger points in patients with chronic shoulder pain: a randomized, controlled trial  

Microsoft Academic Search

BACKGROUND: Shoulder pain is a common musculoskeletal problem that is often chronic or recurrent. Myofascial trigger points (MTrPs) cause shoulder pain and are prevalent in patients with shoulder pain. However, few studies have focused on MTrP therapy. The aim of this study was to assess the effectiveness of multimodal treatment of MTrPs in patients with chronic shoulder pain. METHODS: A

Carel Bron; Arthur de Gast; Jan Dommerholt; Boudewijn Stegenga; Michel Wensing; Rob AB Oostendorp

2011-01-01

307

Proof of principle for an engineered microbial biosensor based on Shewanella oneidensis outer membrane protein complexes.  

PubMed

Shewanella oneidensis is known for its ability to respire on extracellular electron acceptors. The spectrum of these acceptors also includes anode surfaces. Based on this activity, a versatile S. oneidensis based biosensor strain was constructed in which electricity production can be modulated. Construction started with the identification of a usable rate-limiting step of electron transfer to an anode. Thereafter, the sensor strain was genetically engineered to produce a protein complex consisting of the three proteins MtrA, MtrB and MtrF. This complex is associated to the outer membrane and most probably enables membrane spanning electron transfer. MtrF is an outer membrane cytochrome that catalyzes electron transfer reactions on the cell surface. Under anoxic conditions, wild type cells do not express MtrF but rather MtrC as electron transferring outer membrane cytochrome. Still, our analysis revealed that MtrF compared to MtrC overexpression is less toxic to the cell which gives MtrF a superior position for biosensor based applications. Transcription of mtrA, mtrB and mtrF was linked up to an inducible promoter system, which positively reacts to rising l-arabinose concentrations. Anode reduction mediated by this strain was linearly dependent on the arabinose content of the medium. This linear dependency was detectable over a wide range of arabinose concentrations. The l-arabinose biosensor presented in this study proves the principle of an outer membrane complex based sensing method which could be easily modified to different specificities by a simple change of the regulatory elements. PMID:23584391

Golitsch, Frederik; Bücking, Clemens; Gescher, Johannes

2013-09-15

308

A. Higher Radix Technique for Fault Detection in Many-Valued Multithreshold Networks  

Microsoft Academic Search

A technique for fault detection of many-valued multithreshold switching networks is presented. An arbitrary network, implemented with R-valued multithreshold gates, called MT(R), can be transformed into an MT(R + 1) or an MT(R + 2) network which uses additional truth values for fault detection purposes. The technique leads to reduced test sets, which are usually simpler to derive.

A. Druzeta; Zvonko G. Vranesic

1978-01-01

309

Genome-wide expression links the electron transfer pathway of Shewanella oneidensis to chemotaxis  

Microsoft Academic Search

BACKGROUND: By coupling the oxidation of organic substrates to a broad range of terminal electron acceptors (such as nitrate, metals and radionuclides), Shewanella oneidensis MR-1 has the ability to produce current in microbial fuel cells (MFCs). omcA, mtrA, omcB (also known as mtrC), mtrB, and gspF are some known genes of S. oneidensis MR-1 that participate in the process of

Shang-Kai Tai; GuanI Wu; Shinsheng Yuan; Ker-Chau Li

2010-01-01

310

Maternal cerebral venous thrombosis, uncommon but serious disorder, pathologic predictors and contribution of prothrombotic abnormalities.  

PubMed

Cerebral venous thrombosis (CVT) is a rare complication during pregnancy or the puerperium. Our aim was to identify thrombotic risk profiles that predispose to maternal CVT.The study comprised 151 individuals. All participants had a thrombotic workup that included the following: genetic markers: factor V Leiden G1691A and G20210A prothrombin mutations, methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms; protein assays: protein C, protein S and antithrombin; other tests: blood typing and screening for hyperhomocysteinemia. Maternal CVT has been associated with factor V Leiden, the prothrombin G20210A mutation, protein C deficiency and hyperhomocysteinemia. We also speculate that non-O blood groups and preeclampsia could be independent risk factors for CVT. PMID:23337711

Klai, Sarra; Fekih-Mrissa, Najiba; Mrissa, Ridha; Rachdi, Radhouen; Gritli, Nasredine

2013-04-01

311

Methylenetetrahydrofolate reductase gene polymorphisms association with the risk of diffuse large B cell lymphoma: a meta-analysis.  

PubMed

To date, case-control studies on the association between methylenetetrahydrofolate reductase (MTHFR) and diffuse large B cell lymphoma (DLBCL) have provided either controversial or inconclusive results. To clarify the effect of MTHFR on the risk of diffuse large B cell lymphoma, a meta-analysis of all case-control observational studies was performed. The fixed effects and random effects model showed that the C677T polymorphism was associated with a risk of DLBCL among East Asian populations, and A1298C polymorphism was not associated with a risk of DLBCL among Caucasian and East Asian populations. Our pooled data suggest evidence for a major role of MTHFR C677T polymorphism in the carcinogenesis of DLBCL among East Asian populations. PMID:23812728

Sun, Yun-Yu; An, Li; Xie, Yu-Lan; Xu, Jing-Yan; Wang, Jing

2013-12-01

312

Congenital IL-12R1? receptor deficiency and thrombophilia in a girl homozygous for an IL12RB1 mutation and compound heterozygous for MTFHR mutations: A case report and literature review.  

PubMed

Interleukin-12 (IL-12) plays an important role in the production of interferon gamma from T cells and natural killer cells and is essential for protection against intra-macrophagic pathogens such as Mycobacterium and Salmonella. Here, we describe a 16-year-old girl with homozygous mutation in exon 12 of the IL12RB1 gene, which causes complete IL-12R?1 deficiency in association with heterozygous mutation (C677T and A1298C) in the methylenetetrahydrofolate reductase gene. She presented with disseminated Mycobacterium tuberculosis complex infection, retroperitoneal fungal abscess and also thrombosis in the superior mesenteric-portal vein junction. This is the first case report of a primary immunodeficiency associated with a genetically determined venous thrombosis. PMID:24678409

Akar, H H; Kose, M; Ceylan, O; Patiroglu, T; Bustamante, J; Casanova, J L; Akyildiz, B N; Doganay, S

2014-03-01

313

Congenital IL-12R1? receptor deficiency and thrombophilia in a girl homozygous for an IL12RB1 mutation and compound heterozygous for MTFHR mutations: A case report and literature review  

PubMed Central

Interleukin-12 (IL-12) plays an important role in the production of interferon gamma from T cells and natural killer cells and is essential for protection against intra-macrophagic pathogens such as Mycobacterium and Salmonella. Here, we describe a 16-year-old girl with homozygous mutation in exon 12 of the IL12RB1 gene, which causes complete IL-12R?1 deficiency in association with heterozygous mutation (C677T and A1298C) in the methylenetetrahydrofolate reductase gene. She presented with disseminated Mycobacterium tuberculosis complex infection, retroperitoneal fungal abscess and also thrombosis in the superior mesenteric–portal vein junction. This is the first case report of a primary immunodeficiency associated with a genetically determined venous thrombosis.

Kose, M.; Ceylan, O.; Patiroglu, T.; Bustamante, J.; Casanova, J. L.; Akyildiz, B. N.; Doganay, S.

2014-01-01

314

Referred pain elicited by palpation and by needling of myofascial trigger points: A comparison  

Microsoft Academic Search

Objective: To investigate the occurrence of referred pain (REP) elicited by palpation (Pal-ReP) or by needle injection (Inj-ReP) of myofascial trigger point (MTrP), and to assess the correlated factors, including the pain intensity of an active MTrP and the occurrence of local twitch response (LTR).Design: Correlational study.Patients: Ninety-five patients who were treated with MTrP injections.Intervention: MTrP injections.Main Outcome Measure: Pain

Chang-Zern Hong; Ta-Shen Kuan; Jo-Tong Chen; Shu-Min Chen

1997-01-01

315

The NASA modern technology rotors program  

NASA Technical Reports Server (NTRS)

Existing data bases regarding helicopters are based on work conducted on 'old-technology' rotor systems. The Modern Technology Rotors (MTR) Program is to provide extensive data bases on rotor systems using present and emerging technology. The MTR is concerned with modern, four-bladed, rotor systems presently being manufactured or under development. Aspects of MTR philosophy are considered along with instrumentation, the MTR test program, the BV 360 Rotor, and the UH-60 Black Hawk. The program phases include computer modelling, shake test, model-scale test, minimally instrumented flight test, extensively pressure-instrumented-blade flight test, and full-scale wind tunnel test.

Watts, M. E.; Cross, J. L.

1986-01-01

316

Meta-analysis of methylenetetrahydrofolate reductase (MTHFR) polymorphisms affecting methotrexate toxicity  

PubMed Central

Objective Methotrexate is an effective therapy for Rheumatoid Arthritis (RA) but is also associated with toxicity. Pharmacogenetics is the systematic evaluation of the role of genetic differences in the efficacy and toxicity of therapeutic interventions. Because the results of small pharmacogenetic studies are often misleading, we undertook a meta-analysis of published studies to determine the role of polymorphisms in the therapeutic efficacy and toxicity of methotrexate. Methods A search of PUBMED produced 55 publications which were then reviewed for relevance to methotrexate toxicity and efficacy in patients with RA. To ensure that no studies were missed, each polymorphism found was then entered as an independent search string and all results were again reviewed. Results Only 2 polymorphisms (C677T and A1298C in methylenetetrahydrofolate reductase, MTHFR, total: 8 studies) relevant to methotrexate metabolism and efficacy had sufficient data to perform a meta-analysis of their association with toxicity; there was no polymorphism with sufficient data to perform a meta-analysis of efficacy. In a fixed effects model, the C677T polymorphism was associated with increased toxicity (OR 1.71, CI 1.32 – 2.21, p<0.001). The A1298C polymorphism was not associated with increased toxicity (OR 1.12, CI 0.79 – 1.6, p=0.626). Conclusions As pharmacogenetics evolves, more data are needed to assess the role of various polymorphisms for drug efficacy and toxicity. These results illustrate the paucity of reliable pharmacogenetic data on a commonly used anti-rheumatic drug and the potential role of pharmacogenetics in tailoring drug therapy for an individual patient.

Fisher, Mark C.; Cronstein, Bruce N.

2008-01-01

317

Methylenetetrahydrofolate reductase gene variants and antipsychotic-induced weight gain and metabolic disturbances.  

PubMed

Weight gain and metabolic disturbances represent serious side-effects in antipsychotic (AP) treatment, particularly with clozapine and olanzapine. The methylenetetrahydrofolate reductase (MTHFR) gene is a key determinant in the folate metabolism and previous studies reported a significant effect on AP-induced weight gain and related metabolic abnormalities. Thus, we investigated MTHFR gene variants and changes in several important metabolic parameters in AP-treated patients. In this study, two functional MTHFR polymorphisms, rs1801133 (C677T) and rs1801131 (A1298C), were investigated for changes in weight and metabolic parameters. Genotypic associations were evaluated in a large population (n = 347 including 66 first episode psychosis, FEP patients) treated mostly with clozapine and olanzapine. We did not detect any genotypic association with weight changes (p > 0.05) in our total sample and in the sample refined for ancestry and medication. In our allelic analyses, we observed a trend for the 677-C allele to be associated with weight gain in the total sample (p = 0.03). This effect appeared to be driven by the FEP patients where those carrying the C-allele gained, on average, twice as much weight. Exploratory analyses revealed a significant association between the C677T and the A1298C polymorphism with HDL cholesterol serum levels in patients (p = 0.031). Overall we did not detect a major effect of two functional MTHFR gene variants and AP-induced weight gain. However, our findings suggest an effect of the C677T polymorphism in FEP patients and changes in weight and cholesterol levels. Further investigations in a larger sample are required. PMID:24725652

Kao, A C C; Rojnic Kuzman, M; Tiwari, A K; Zivkovic, M V; Chowdhury, N I; Medved, V; Kekin, I; Zai, C C; Lieberman, J A; Meltzer, H Y; Bozina, T; Bozina, N; Kennedy, J L; Sertic, J; Müller, D J

2014-07-01

318

Impact of MTHFR polymorphisms on methylation of MGMT in glioma patients from Northeast China with different folate levels.  

PubMed

Hypomethylation of the O6-methylguanine-DNA-methyltransferase (MGMT) promoter in glioma cells has been associated with temozolomide resistance. S-adenosylmethionine (SAM), which is produced during folate metabolism, is the main source of methyl groups during DNA methylation. As a key enzyme during folate metabolism, polymorphisms of 5,10-methylenetetrahydrofolate reductase (MTHFR) may regulate folate end-products. We investigated the effect of typical polymorphisms of MTHFR (C677T and A1298C) on MGMT methylation based on different serum folate levels in patients with glioma from Northeast China. A total of 275 patients with glioma and 329 without malignant tumors were tested. Serum folate concentration was assayed by using the electrochemiluminescence immunoassay. MTHFR polymorphisms were detected by Taqman-Fluorescence quantitative polymerase chain reaction (PCR). Methylation-specific PCR was used to assess MGMT methylation. The constituent ratio of glioma patients below the serum folate biological reference value was significantly higher than that of the control population (P < 0.001). In patients with oligodendroglioma and glioblastoma, heterozygotes for the A1298C mutation were found in higher frequency than homozygotes or wild types (oligodendroglioma, P < 0.001; glioblastoma, P < 0.01). When grouped by the median or biological reference value of serum folate, only homozygotes for C677T with low levels of folate were significantly associated with decreased methylation of MGMT (median, P < 0.001; biological reference value, P = 0.036). These data suggest that, in combination with a negative folate balance in glioma patients, T/T genotypes in MTHFR C677T may be associated with MGMT demethylation. PMID:24301776

Liu, N; Jiang, J; Song, Y J; Zhao, S G; Tong, Z G; Song, H S; Wu, H; Zhu, J Y; Gu, Y H; Sun, Y; Hua, W; Qi, J P

2013-01-01

319

Development of metronidazole-resistant lines of Blastocystis sp.  

PubMed

Metronidazole (MTR) is frequently used for the treatment of Blastocystis infections, but with variable effectiveness, and often with treatment failures as a possible result of drug resistance. We have developed two Blastocystis MTR-resistant (MTR(R)) subtype 4 WR1 lines (WR1-M4 and WR1-M5), with variable susceptibility to a panel of anti-protozoal agents including various 5-nitroimidazoles, nitazoxanide and furazolidone. WR1-M4 and WR1-M5 were developed and assessed over an 18-month period and displayed persistent MTR resistance, being more than 2.5-fold less susceptible to MTR than the parent isolate. The MTR(R) lines grew with a similar g time to WR1, but were morphologically less consistent with a mixture of size. All Blastocystis isolates and the MTR(R) lines were most susceptible to the 5-nitroimidazole drug ronidazole. WR1-M5 was apparently cross-resistant to satranidazole and furazolidone, and WR1-M4 was cross-resistant to nitazoxanide. These MTR(R) lines now provide a valuable tool for the continued assessment of the efficacy and mechanism of action of new and established drugs against a range of Blastocystis sp. subtypes, in order to identify a universally effective drug and to facilitate understanding of the mechanisms of drug action and resistance in Blastocystis. PMID:22362365

Dunn, L A; Tan, K S W; Vanelle, P; Juspin, T; Crozet, M D; Terme, T; Upcroft, P; Upcroft, J A

2012-07-01

320

Interrater reliability in myofascial trigger point examination  

Microsoft Academic Search

The myofascial trigger point (MTrP) is the hallmark physical finding of the myofascial pain syndrome (MPS). The MTrP itself is characterized by distinctive physical features that include a tender point in a taut band of muscle, a local twitch response (LTR) to mechanical stimulation, a pain referral pattern characteristic of trigger points of specific areas in each muscle, and the

Robert D. Gerwin; Steven Shannon; Chang-Zern Hong; David Hubbard; Richard Gevirtz

1997-01-01

321

Magnetisation transfer ratio in optic neuritis is associated with axonal loss, but not with demyelination  

Microsoft Academic Search

BackgroundPathophysiological basis of Magnetisation Transfer Ratio (MTR) reduction in multiple sclerosis still remains a matter of controversy. Optic nerve represents an ideal model to study the consequences of axonal loss and demyelination on MTR since effects of disease on the optic nerve are clinically apparent and potentially quantifiable by objective means. By measuring the latency of multifocal visual evoked potentials

A. Klistorner; J. Chaganti; R. Garrick; K. Moffat; C. Yiannikas

2011-01-01

322

How IMS can achieve ISO 9001:2000 certification  

Microsoft Academic Search

A significant milestone of the quality journey of the MTR Corporation (MTR) was the establishment of the ISO 9000-based quality management system (QMS) in its core departments. Adopting the ISO 9000 standards, the QMS provided a framework for the Corporation’s quality, safety and environmental management systems, linking and standardizing all work processes from the top management down to the shopfloor.

Y. K. Chan; Jacob Kam; K. Neailey; W. H. Ip

2002-01-01

323

Production of 5-Methlthioribose by 'Escherichia coli.'.  

National Technical Information Service (NTIS)

A study of sulfur metabolism in micro-organisms led to the isolation and identification of 5-methylthioribose (MTR) from E. coli B. MTR labeled with 35S was excreted by the bacterium during incubation in glucose-salts medium supplemented with 35SO4(-2). I...

M. F. Mallette

1972-01-01

324

33 CFR 154.1065 - Plan review and revision procedures.  

Code of Federal Regulations, 2013 CFR

...the ACP in effect 6 months prior to plan review. (1) For an MTR facility identified in § 154.1015(c) of this subpart as a...of the anniversary date of COTP approval of the plan. For an MTR facility identified in § 154.1015(b) of this subpart,...

2013-07-01

325

FAST CHOPPER BUILDING, TRA665. CONTEXTUAL VIEW: CHOPPER BUILDING IN CENTER. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FAST CHOPPER BUILDING, TRA-665. CONTEXTUAL VIEW: CHOPPER BUILDING IN CENTER. MTR REACTOR SERVICES BUILDING,TRA-635, TO LEFT; MTR BUILDING TO RIGHT. CAMERA FACING WEST. INL NEGATIVE NO. HD42-1. Mike Crane, Photographer, 3/2004 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

326

MTRETR MAINTENANCE SHOP, TRA653. ELEVATIONS. WINDOW TYPES. HUMMEL HUMMEL & ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR-ETR MAINTENANCE SHOP, TRA-653. ELEVATIONS. WINDOW TYPES. HUMMEL HUMMEL & JONES 810-MTR-ETR-653-A-4, 11/1956. INL INDEX NO. 532-0653-00-381-101836, REV. 1. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

327

Magnetisation transfer ratio of normal brain white matter: a normative database spanning four decades of life  

Microsoft Academic Search

OBJECTIVES: To establish a normative database for magnetisation transfer ratio (MTR) measurements in the white matter of healthy adult brains. Such MTR values were evaluated for regional variation and evidence of differences associated with aging, sex, and handedness. METHODS: Forty one healthy volunteers, ranging in age from 16 to 55 years, underwent axial brain magnetisation transfer (MT) imaging on a

N C Silver; G J Barker; D G MacManus; P S Tofts; D H Miller

1997-01-01

328

33 CFR 154.1025 - Operating restrictions and interim operating authorization.  

Code of Federal Regulations, 2013 CFR

...operating authorization. (a) The owner or operator of an MTR facility who submitted a response plan prior to May 29, 1996...in accordance with § 154.1065. An owner or operator of an MTR facility who elects to comply with all sections of this...

2013-07-01

329

Export of detritus and invertebrate from headwater streams: linking mountaintop removal and valley fill coal mining to downstream receiving waters  

EPA Science Inventory

Mountaintop removal and valley fill (MTR/VF) coal mining has resulted in large scale alteration of the topography, reduced forest productivity, and burial of headwater streams in the U.S. Central Appalachians. Although MTR/VF coal mining has occurred for several decades and the ...

330

Integrated Autonomous Network Management (IANM) Multi-Topology Route Manager and Analyzer.  

National Technical Information Service (NTIS)

This report documents the Multi-Topology Routing (MTR) Route Manager and Analyzer (RMA) program for The Boeing Company under Office of Naval Research (ONR) Contract N00014-05-C-0012. The MTR RMA program ran from July 2005 through February 2008, and was pa...

D. M. Kushi J. Fang K. Bae T. R. Henderson

2008-01-01

331

A simple correction for B 1 field errors in magnetization transfer ratio measurements  

Microsoft Academic Search

B1 errors are a problem in magnetization transfer ratio (MTR) measurements because the MTR value is dependent on the amplitude of the magnetization transfer (MT) pulse. B1 errors can arise from radiofrequency (RF) nonuniformity (caused by the RF coil, or skin effect and dielectric resonance in the subject's head) and also from inaccurate setting of the transmitter output when compensating

Rebecca S. Samson; Claudia A. M. Wheeler-Kingshott; Mark R. Symms; Daniel J. Tozer; Paul S. Tofts

2006-01-01

332

ANP COMPRESSOR BUILDING, TRA626, UNDER CONSTRUCTION ALONG EAST WALL OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ANP COMPRESSOR BUILDING, TRA-626, UNDER CONSTRUCTION ALONG EAST WALL OF MTR BUILDING. CAMERA FACES SOUTH. AIR RECEIVING TANKS WERE SET UP AND THE WALLS CONSTRUCTED AROUND THEM. CONNECTIONS BETWEEN THE COMPRESSOR BUILDING AND THE MTR WERE BELOW GROUND. INL NEGATIVE NO. 6089. Unknown Photographer, 6/25/1952 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

333

MTRETR MAINTENANCE SHOP, TRA653. LONGITUDINAL AND TRANSVERSE SECTIONS. DETAIL OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR-ETR MAINTENANCE SHOP, TRA-653. LONGITUDINAL AND TRANSVERSE SECTIONS. DETAIL OF DOORWAY LINTEL. HUMMEL HUMMEL & JONES 810-MTR-ETR-653-A-9, 5/1957. INL INDEX NO. 532-0653-00-381-101841H, REV. 1. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

334

MTRETR MAINTENANCE SHOP, TRA653. FLOOR PLAN FOR MEZZANINE: LUNCH AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR-ETR MAINTENANCE SHOP, TRA-653. FLOOR PLAN FOR MEZZANINE: LUNCH AND CONFERENCE ROOM, STORAGE AREA, OFFICES FOR FOREMEN, STENOS, ENGINEERS, DISPATCHER, WOMEN'S RESTROOM. HUMMEL HUMMEL & JONES 810-MTR-ETR-653-A-12, 2/1958. INL INDEX NO. 532-0653-00-381-102837, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

335

Modelagem de Radiancias Emergentes Do Sistema Terra-Atmosfera Para Calibracao de Imageadores No Visivel (Upwelling Radiance Modelling from the Earth-Atmosphere System for Calibration of Sensors in the Visible Channel).  

National Technical Information Service (NTIS)

In this work, physical-mathematical shortwave radiative transfer models were used to estimate the top of the atmosphere upwelling radiances for clear skies (MTR-CA) and stratiform cloud covered (MTR-CN) conditions. The main objective was the vicarious cal...

E. J. Debritobastos

1994-01-01

336

Molecular cloning, pharmacological characterization, and histochemical distribution of frog vasotocin and mesotocin receptors  

Microsoft Academic Search

The neurohypophysial nonapeptides vasotocin (VT) and mesotocin (MT) are the amphibian counterparts of arginine vasopressin (AVP) and oxytocin (OT). We have here reported the cloning and functional characterization of the receptors for vasotocin (VTR) and mesotocin (MTR) in two species of frog, Rana catesbeiana and Rana esculenta. The frog VTR and MTR cDNAs encode proteins of 419 and 384 amino

S Acharjee; J-L Do-Rego; D Y Oh; R S Ahn; K Lee; D G Bai; H Vaudry; H B Kwon; J Y Seong

2004-01-01

337

[Muscular-arterial nociceptive reflex in patients with primary headaches].  

PubMed

Authors studied 192 patients with migraine, tension-type headache (TTH) and cluster headache (CH). Active muscle trigger points (MTrP) were found at 84.2% migraineurs, 97.6% patients with TTH and at 100% patient with CH. MTrP were frequently found in the splenius muscle of head (96.8%), trapezius muscle (86.5%) and splenius muscle of neck (83.8%). Pressure to the MTrP at the trapezius muscle or splenius muscle of head caused the blood flow velocity (BFV) increase in the medial cerebral artery (MCA) and the Lindegaard ratio (LR) elevation within the range of 2 to 3 (a feature of functional vasoconstriction). The increase of BFV in MCA and LR in patients with primary headaches with active MTrP before treatment and the normalization of these values (BFV in MCA and LR) after treatment are evidence of MTrP influence on the cerebral arteries tone. PMID:24637811

2014-01-01

338

Short Telomeres Result in Organismal Hypersensitivity to Ionizing Radiation in Mammals  

PubMed Central

Here we show a correlation between telomere length and organismal sensitivity to ionizing radiation (IR) in mammals. In particular, fifth generation (G5) mouse telomerase RNA (mTR)?/? mice, with telomeres 40% shorter than in wild-type mice, are hypersensitive to cumulative doses of gamma rays. 60% of the irradiated G5 mTR?/? mice die of acute radiation toxicity in the gastrointestinal tract, lymphoid organs, and kidney. The affected G5 mTR?/? mice show higher chromosomal damage and greater apoptosis than similarly irradiated wild-type controls. Furthermore, we show that G5 mTR?/? mice show normal frequencies of sister chromatid exchange and normal V(D)J recombination, suggesting that short telomeres do not significantly affect the efficiency of DNA double strand break repair in mammals. The IR-sensitive phenotype of G5 mTR?/? mice suggests that telomere function is one of the determinants of radiation sensitivity of whole animals.

Goytisolo, Fermin A.; Samper, Enrique; Martin-Caballero, Juan; Finnon, Paul; Herrera, Eloisa; Flores, Juana M.; Bouffler, Simon D.; Blasco, Maria A.

2000-01-01

339

Metabolism of 5-methylthioribose to methionine  

SciTech Connect

During ethylene biosynthesis, the H/sub 3/CS-group of S-adenosylmethionine is released as 5'-methylthioadenosine, which is recycled to methionine via 5-methylthioribose (MTR). In mungbean hypocotyls and cell-free extracts of avocado, (/sup 14/C)MTR was converted into labeled methionine via 2-keto-4-methylthiobutyric acid (KMB) and 2-hydroxy-4-methylthiobutyric acid (HMB), as intermediates. Incubation of (ribose-U-/sup 14/C)MTR with avocado extract resulted in the production of (/sup 14/C)formate, indicating the conversion of MTR to KMB involves a loss of formate, presumably from C-1 of MTR. Tracer studies showed that KMB was converted readily in vivo and in vitro to methionine, while HMB was converted much more slowly. The conversion of KMB to methionine by dialyzed avocado extract requires an amino donor. Among several potential donors examined, L-glutamine was the most efficient. Anaerobiosis inhibited only partially the oxidation of MTR to formate, KMB/HMB, and methionine by avocado extract. The role of O/sub 2/ in the conversion of MTR to methionine is discussed.

Miyazaki, J.H.; Yang, S.F.

1987-06-01

340

Optic nerve magnetisation transfer ratio after acute optic neuritis predicts axonal and visual outcomes.  

PubMed

Magnetisation transfer ratio (MTR) can reveal the degree of proton exchange between free water and macromolecules and was suggested to be pathological informative. We aimed to investigate changes in optic nerve MTR over 12 months following acute optic neuritis (ON) and to determine whether MTR measurements can predict clinical and paraclinical outcomes at 6 and 12 months. Thirty-seven patients with acute ON were studied within 2 weeks of presentation and at 1, 3, 6 and 12 months. Assessments included optic nerve MTR, retinal nerve fibre layer (RNFL) thickness, multifocal visual evoked potential (mfVEP) amplitude and latency and high (100%) and low (2.5%) contrast letter acuity. Eleven healthy controls were scanned twice four weeks apart for comparison with patients. Patient unaffected optic nerve MTR did not significantly differ from controls at any time-point. Compared to the unaffected nerve, affected optic nerve MTR was significantly reduced at 3 months (mean percentage interocular difference?=?-9.24%, p?=?0.01), 6 months (mean?=?-12.48%, p<0.0001) and 12 months (mean?=?-7.61%, p?=?0.003). Greater reduction in MTR at 3 months in patients was associated with subsequent loss of high contrast letter acuity at 6 (??=?0.60, p?=?0.0003) and 12 (??=?0.44, p?=?0.009) months, low contrast letter acuity at 6 (??=?0.35, p?=?0.047) months, and RNFL thinning at 12 (??=?0.35, p?=?0.044) months. Stratification of individual patient MTR time courses based on flux over 12 months (stable, putative remyelination and putative degeneration) predicted RNFL thinning at 12 months (F(2,32)?=?3.59, p?=?0.02). In conclusion, these findings indicate that MTR flux after acute ON is predictive of axonal degeneration and visual disability outcomes. PMID:23272235

Wang, Yejun; van der Walt, Anneke; Paine, Mark; Klistorner, Alexander; Butzkueven, Helmut; Egan, Gary F; Kilpatrick, Trevor J; Kolbe, Scott C

2012-01-01

341

Genetic Mediators of Neurocognitive Outcomes in Survivors of Childhood Acute Lymphoblastic Leukemia  

PubMed Central

Purpose Survivors of childhood acute lymphoblastic leukemia (ALL) are at increased risk for neurocognitive problems, with significant interindividual variability in outcome. This study examined genetic polymorphisms associated with variability in neurocognitive outcome. Patients and Methods Neurocognitive outcomes were evaluated at the end of therapy in 243 survivors treated on an institutional protocol featuring risk-adapted chemotherapy without prophylactic cranial irradiation. Polymorphisms in genes related to pharmacokinetics or pharmacodynamics of antileukemic agents, drug metabolism, oxidative stress, and attention problems in noncancer populations were examined as predictors of outcome, using multiple general linear models and controlling for age at diagnosis, sex, race, and treatment intensity. Results Compared with national norms, the cohort demonstrated significantly higher rates of problems on direct assessment of sustained attention (P = .01) and on parent ratings of attention problems (P = .02). Children with the A2756G polymorphism in methionine synthase (MS) were more likely to demonstrate deficits in attentiveness (P = .03) and response speed (P = .02), whereas those with various polymorphisms in glutathione S-transferase demonstrated increased performance variability (P = .01) and reduced attentiveness (P = .003). Polymorphisms in monoamine oxidase (T1460CA) were associated with increased attention variability (P = .03). Parent-reported attention problems were more common in children with the Cys112Arg polymorphism in apoliopoprotein E4 (P = .01). Conclusion These results are consistent with our previous report of association between attention problems and MS in an independent cohort of long-term survivors of childhood ALL treated with chemotherapy only. The results also raise the possibility of an impact from genetic predispositions related to oxidative stress and CNS integrity.

Krull, Kevin R.; Bhojwani, Deepa; Conklin, Heather M.; Pei, Deqing; Cheng, Cheng; Reddick, Wilburn E.; Sandlund, John T.; Pui, Ching-Hon

2013-01-01

342

[Neural tube defects and vitamin B12: a report of three cases].  

PubMed

Periconceptional folic acid supplementation reduces the frequency of embryological neural tube defects (NTD). This fact led the USA to fortify grain products with folic acid (140 microg/100 g) starting in January 1998, with a resultant decrease in the incidence of NTD. Folate deficiency is thus confirmed to be a risk factor for NTD. However, in a prospective study, we investigated three women who conceived a fetus with NTD; no folate deficiency was found in these women but all three had decreased vitamin B12 levels (cobalamin), which can be an other risk factor. Samples were obtained from two women in Algeria, 2 days after interruption of pregnancy, and from a vegetarian woman, in France, one month after interruption of pregnancy. Red cell folate and plasma folate, vitamin B12, B6 and homocysteine were assayed and the mutations C677T (in metylenetetrahydrofolate reductase gene), A2756G (in methionine synthase gene) and A66G (in methionine synthase reductase gene) were sought. Elevated plasma folate levels were found in both Algerian women. Vitamin B 12 levels in all three women were decreased or in the lowest quartile of normal values. One woman presented simultaneously a vitamin B 12 deficiency, and heterozygous mutations in the three genes. The second woman presented a A66G homozygous mutation and the third heterozygous C677T and A66G mutations. Acquired and inborn factors are intricated in some cases of pregnancies with NTD and B 12 deficiency can be responsible for intracellular folate cycle failure. It would therefore be advisable to consider fortifying grain products with both folic acid and vitamin B12. PMID:15047478

Candito, M; Houcher, B; Boisson, C; Abellard, J; Demarcq, M-J; Guéant, J-L; Benhacine, K; Gérard, P; Van Obberghen, E

2004-01-01

343

Identification and characterization of MTR1, a novel gene with homology to melastatin (MLSN1) and the trp gene family located in the BWS-WT2 critical region on chromosome 11p15.5 and showing allele-specific expression  

Microsoft Academic Search

Alterations within human chromosomal region 11p15.5 are associated with the Beckwith-Wiedemann syndrome (BWS) and predisposition to a variety of neoplasias, including Wilms' tumors (WTs), rhabdoid tumors and rhabdomyosarcomas. To identify candidate genes for 11p15.5-related diseases we compared human genomic sequence with expressed sequence tag and protein databases from different organisms to discover evolutionarily conserved sequences. Herein we describe the identification

Dirk Prawitt; Thorsten Enklaar; Gabi Klemm; Barbara Gärtner; Christian Spangenberg; Andreas Winterpacht; Michael Higgins; Jerry Pelletier; Bernhard Zabel

2000-01-01

344

Induction of muscle cramps by nociceptive stimulation of latent myofascial trigger points  

Microsoft Academic Search

The aim of this present study is to test the hypothesis that nociceptive stimulation of latent myofascial trigger points (MTrPs)\\u000a increases the occurrence of local muscle cramps. Nociceptive muscle stimulation was obtained by a bolus injection of glutamate\\u000a (0.1 ml, 0.5 M) into a latent MTrP and a control point (a non-MTrP) located in the right or left gastrocnemius medialis muscles\\u000a in

Hong-You Ge; Yang Zhang; Shellie Boudreau; Shou-Wei Yue; Lars Arendt-Nielsen

2008-01-01

345

Topographical mapping and mechanical pain sensitivity of myofascial trigger points in the infraspinatus muscle  

Microsoft Academic Search

ObjectivesTo screen for the presence of latent and active myofascial trigger points (MTrPs) in patients with unilateral shoulder and arm pain and perform topographical mapping of mechanical pain sensitivity bilaterally in the infraspinatus muscles.

Hong-You Ge; César Fernández-de-las-Peñas; Pascal Madeleine; Lars Arendt-Nielsen

2008-01-01

346

76 FR 74116 - Alabama & Florida Railway Co., Inc. d/b/a Ripley & New Albany Railroad Co.-Acquisition and...  

Federal Register 2010, 2011, 2012, 2013

...New Albany Railroad Co. (RNA), a Class III rail carrier...and Tippah Counties, Miss. RNA states that it proposes to acquire...right-of-way, track and structures, as well as MTR's leasehold...RNA certifies that its...

2011-11-30

347

33 CFR 154.1010 - Purpose.  

Code of Federal Regulations, 2013 CFR

...1010 Purpose. This subpart establishes oil spill response plan requirements for all marine transportation-related (MTR) facilities (hereafter also referred to as facilities) that could reasonably be expected to cause substantial harm or...

2013-07-01

348

40 CFR 63.5698 - What emission limit must I meet for open molding resin and gel coat operations?  

Code of Federal Regulations, 2013 CFR

...clear gel coat used in the past 12 months, excluding any materials exempt under paragraph (d) of this section, megagrams. MTR = mass of tooling resin used in the past 12 months, excluding any materials exempt under paragraph (d) of this...

2013-07-01

349

31 CFR 344.7 - What are Demand Deposit securities?  

Code of Federal Regulations, 2013 CFR

...day). DTM = The number of days from date of issue to maturity for the most recently auctioned 13-week Treasury bill. MTR = Estimated marginal tax rate, in decimals, of purchasers of tax-exempt bonds. TAC = Treasury administrative costs,...

2013-07-01

350

Molecular Underpinnings of Fe(III) Oxide Reduction by Shewanella oneidensis MR-1  

SciTech Connect

In the absence of O2 and other electron acceptors, the Gram-negative bacterium Shewanella oneidensis MR-1 can use ferric [Fe(III)] (oxy)(hydr)oxide minerals as the terminal electron acceptors for anaerobic respiration. At circumneutral pH and in the absence of strong complexing ligands, Fe(III) oxides are relatively insoluble and thus are external to the bacterial cells. S. oneidensis MR-1 and related strains of metal-reducing Shewanella have evolved the machinery (i.e., metal-reducing or Mtr pathway) for transferring electrons from the inner-membrane, through the periplasm and across the outer-membrane to the surface of extracellular Fe(III) oxides. The protein components identified to date for the Mtr pathway include CymA, MtrA, MtrB, MtrC and OmcA. CymA is an inner-membrane tetraheme c-type cytochrome (c-Cyt) that belongs to the NapC/NrfH family of quinol dehydrogenases. It is proposed that CymA oxidizes the quinol in the inner-membrane and transfers the released electrons to redox proteins in the periplasm. Although the periplasmic proteins receiving electrons from CymA during Fe(III) oxidation have not been identified, they are believed to relay the electrons in the periplasm to MtrA. A decaheme c-Cyt, MtrA is thought to be embedded in the trans outer-membrane and porin-like protein MtrB. Together, MtrAB deliver the electrons through the outer-membrane to the MtrC and OmcA on the outmost bacterial surface. MtrC and OmcA are the outer-membrane decaheme c-Cyts that are translocated across the outer-membrane by the bacterial type II secretion system. Functioning as terminal reductases, MtrC and OmcA can bind the surface of Fe(III) oxides and transfer electrons directly to these minerals via their solvent-exposed hemes. To increase their reaction rates, MtrC and OmcA can use the flavins secreted by S. oneidensis MR-1 cells as diffusible co-factors for reduction of Fe(III) oxides. Because of their extracellular location and broad redox potentials, MtrC and OmcA can also serve as the terminal reductases for soluble forms of Fe(III). Although our understanding of the Mtr pathway is still far from complete, it is the best characterized microbial pathway used for extracellular electron exchange. Characterizations of the Mtr pathway have made significant contributions to the molecular understanding of microbial reduction of Fe(III) oxides.

Shi, Liang; Rosso, Kevin M.; Clarke, Thomas A.; Richardson, David J.; Zachara, John M.; Fredrickson, Jim K.

2012-02-15

351

40 CFR 63.5710 - How do I demonstrate compliance using emissions averaging?  

Code of Federal Regulations, 2013 CFR

... PVTR = Weighted-average MACT model point value for tooling resin used in the past 12 months, kilograms per megagram. MTR = Mass of tooling resin used in the past 12 months, megagrams. PVTG = Weighted-average MACT model point value...

2013-07-01

352

Validacion experimental del metodo de elementos finitos heterogeneos generados a partir de soluciones halladas con probabilidades de colision. (Use of heterogeneous finite elements generated by collision probability solutions to calculate a pool reactor core).  

National Technical Information Service (NTIS)

This work presents comparisons between measured fluxes obtained by activation of Manganese foils in the light water, enriched uranium research pool reactor RA-2 MTR (Materials Testing Reactors) fuel element and fluxes calculated by the finite element meth...

C. R. Calabrese C. R. Grant

1990-01-01

353

A hybrid method combining the multitemporal resolution time-domain method of moments with the time-domain geometrical theory of diffraction for thin-wire antenna problems  

Microsoft Academic Search

In this paper, a hybrid method combining a multitemporal resolution (MTR) enhanced time-domain method of moments (TD-MoM) with the TD geometrical theory of diffraction (GTD) is presented, which allows to efficiently calculate the transient fields radiated by antennas in presence of large objects. The MTR scheme tailors the time step size-and thus implicitly the duration of the temporal basis function-on

Andreas Becker; Volkert Hansen

2006-01-01

354

Depth dose distributions measured with thermoluminescence detectors inside the anthropomorphic torso of the MATROSHKA experiment inside and outside the ISS  

NASA Astrophysics Data System (ADS)

The ESA MATROSHKA (MTR) facility was realized through the German Aerospace Center, DLR, Cologne, as main contractor, aiming for the determination of skin and organ doses within a simulated human upper torso. MTR simulates, by applying an anthropomorphic upper torso, as exact as possible an astronaut performing either an extravehicular activity (EVA) (MTR Phase 1) or an astronaut working inside the International Space Station (MTR Phase 2A). It consists of a human phantom, a Base Structure and a Carbon fibre container - simulating the astronaut‘s space suit. The phantom itself is made up of 33 slices composed of natural bones, embedded in tissue equivalent plastic of different density for tissue and lung. The Phantom slices are equipped with channels and cut-outs to allow the accommodation of active and passive dosemeters, temperature and pressure sensors. Over 4800 passive detectors (thermoluminescence detectors (TLDs) and plastic nuclear track detectors) constitute the radiation experiments which are beside inside the phantom also located on top the head of the phantom, in front of the belly and around the body as part of a Poncho and a Hood. In its 1st exposure phase (MTR 1: 2004 - 2005) MTR measured the depth dose distribution of an astronaut performing an EVA - mounted outside the Zvezda Module. In its 2nd exposure phase the phantom was positioned inside the ISS to monitor the radiation environment and measure the depth dose distribution in dependence on the inside shielding configurations. The majority of the TLDs provided for the determination of the depth dose distribution was provided by IFJ-PAN, ATI and DLR. Data of "combined" depth dose distribution of the three different groups will be shown for the MTR-1 exposure (outside the ISS) and the MTR-2A (inside the ISS). The discussion will focus on the difference in depth dose as well as skin dose distribution based on the different shielding thickness provided by the two experimental phases.

Berger, Thomas; Reitz, Guenther; Hajek, Michael; Bergmann, Robert; Bilski, Pawel; Puchalska, Msc. Monika

355

Treatment of myofascial trigger-points with ultrasound combined with massage and exercise – a randomised controlled trial  

Microsoft Academic Search

The effect of treatment with ultrasound, massage and exercises on myofascial trigger-points (MTrP) in the neck and shoulder was assessed in a randomised controlled trial. The outcome measures were pain at rest and on daily function (Visual Analogue Scale, VAS), analgesic usage, global preference and index of MTrP. Long-term effect for treatment and control groups was assessed after 6 months

Arne N Gam; Lone Hørdum Larsen; Bente Jensen; Ola Høydalsmo; Ingelise Allon; Bente Andersen; Niels E Gøtzsche; Marelis Petersen; Birgitte Mathiesen

1998-01-01

356

Gonococcal Resistance to b-Lactams and Tetracycline Involves Mutation in Loop 3 of the Porin Encoded at the penB Locus  

Microsoft Academic Search

penB is a chromosomal mutation that confers resistance to b-lactams and tetracyclines and reduced sus- ceptibility to quinolones in Neisseria gonorrhoeae. It is linked to the porin gene (por) and requires the increased expression of an efflux pump due to mtr. Transformation of a susceptible gonococcus (strain H1) with chro- mosomal DNA from strain FA140 (penA mtr penB; porin serovar

M. J. GILL; S. SIMJEE; K. AL-HATTAWI; B. D. ROBERTSON; C. S. F. EASMON; C. A. ISON

1998-01-01

357

Bacterial Nanowires Facilitate Extracellular Electron Transfer  

Microsoft Academic Search

Dissimilatory metal reducing bacteria, including Shewanella oneidensis and Geobacter sulfurreducens, produce electrically conductive nanowires that facilitate electron transfer to solid phase iron oxides. Nanowires produced by S. oneidensis strain MR-1 are functionalized by decaheme cytochromes MtrC and OmcA that are distributed along the length of the nanowires, as confirmed by immunolocalization experiments using peptide specific antibodies. Mutants lacking MtrC and

Y. Gorby

2005-01-01

358

Effectiveness of dry needling and injections of myofascial trigger points associated with plantar heel pain: a systematic review  

Microsoft Academic Search

BACKGROUND: Plantar heel pain (plantar fasciitis) is one of the most common musculoskeletal pathologies of the foot. Plantar heel pain can be managed with dry needling and\\/or injection of myofascial trigger points (MTrPs) however the evidence for its effectiveness is uncertain. Therefore, we aimed to systematically review the current evidence for the effectiveness of dry needling and\\/or injections of MTrPs

Matthew P Cotchett; Karl B Landorf; Shannon E Munteanu

2010-01-01

359

Vitamin B12 Is a Strong Determinant of Low Methionine Synthase Activity and DNA Hypomethylation in Gastrectomized Rats  

Microsoft Academic Search

Background\\/Aims: The respective influence of folate and vitamin B12 deficiency on MTR activity and transcription, and on DNA methylation is not clearly established. The aim of this study was to assess the respective influence of folate and vitamin B12 deficiency on MTR transcription and activity, and on DNA methylation. Methods: Sixty-one rats were administered normal diet or diet deficient in

Laurent Brunaud; Jean-Marc Alberto; Ahmet Ayav; Philippe Gérard; Farès Namour; Laurent Antunes; Marc Braun; Jean-Pierre Bronowicki; Laurent Bresler; Jean-Louis Guéant

2003-01-01

360

The Shortest Telomere, Not Average Telomere Length, Is Critical for Cell Viability and Chromosome Stability  

Microsoft Academic Search

Loss of telomere function can induce cell cycle arrest and apoptosis. To investigate the processes that trigger cellular responses to telomere dysfunction, we crossed mTR?\\/? G6 mice that have short telomeres with mice heterozygous for telomerase (mTR+\\/?) that have long telomeres. The phenotype of the telomerase null offspring was similar to that of the late generation parent, although only half

Michael T Hemann; Margaret A Strong; Ling-Yang Hao; Carol W Greider

2001-01-01

361

Hepatic cirrhosis: magnetisation transfer contrast in the globus pallidus  

Microsoft Academic Search

The magnetisation transfer ratio (MTR), a quantitative tissue characteristic, and the pallidal index were measured in the\\u000a globus pallidus of 37 patients with hepatic cirrhosis and 37 control subjects. The MTR decreased with severity of the disease,\\u000a as indicated by the serum total bililubin, indocyanine green 15-min retention rate, and plasma ammonia. The pallidal index\\u000a correlated significantly with haematological parameters,

M. Iwasa; Y. Kinosada; S. Watanabe; M. Furuta; H. Yuda; N. Kawamura; M. Nakayabu; A. Esaki; T. Sato; T. Deguchi; A. Nakatsuka; Y. Adachi

1998-01-01

362

Magnetization transfer analysis of cartilage repair tissue: a preliminary study  

Microsoft Academic Search

Purpose  To evaluate the magnetization transfer ratio (MTR) after two different cartilage repair procedures, and to compare these data with the MTR of normal cartilage.Design and patients  Twenty-seven patients with a proven cartilage defect were recruited: 13 were treated with autologous chondrocyte implantation (ACI) and 14 were treated with the microfracture technique (MFR). All patients underwent MRI examinations with MT-sequences before the

F. Palmieri; F. De Keyzer; F. Maes; I. Van Breuseghem

2006-01-01

363

REACTOR SERVICE BUILDING, TRA635, INTERIOR. CAMERA FACES NORTHWEST TOWARDS INTERIOR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

REACTOR SERVICE BUILDING, TRA-635, INTERIOR. CAMERA FACES NORTHWEST TOWARDS INTERIOR WALL ENCLOSING STORAGE AND OFFICE SPACE ALONG THE WEST SIDE. AT RIGHT EDGE IS DOOR TO MTR BUILDING. FROM RIGHT TO LEFT, SPACE WAS PLANNED FOR A LOCKER ROOM, MTR ISSUE ROOM, AND STORAGE AREAS AND RELATED OFFICES. NOTE SECOND "MEZZANINE" FLOOR ABOVE. INL NEGATIVE NO. 10227. Unknown Photographer, 3/23/1954 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

364

FAST CHOPPER BUILDING, TRA665. CAMERA FACING NORTH. NOTE BRICKEDIN WINDOW ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FAST CHOPPER BUILDING, TRA-665. CAMERA FACING NORTH. NOTE BRICKED-IN WINDOW ON RIGHT SIDE (BELOW PAINTED NUMERALS "665"). SLIDING METAL DOOR ON COVERED RAIL AT UPPER LEVEL. SHELTERED ENTRANCE TO STEEL SHIELDING DOOR. DOOR INTO MTR SERVICE BUILDING, TRA-635, STANDS OPEN. MTR BEHIND CHOPPER BUILDING. INL NEGATIVE NO. HD42-1. Mike Crane, Photographer, 3/2004 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

365

Deep Gray Matter Demyelination Detected by Magnetization Transfer Ratio in the Cuprizone Model  

PubMed Central

In multiple sclerosis (MS), the correlation between lesion load on conventional magnetic resonance imaging (MRI) and clinical disability is weak. This clinico-radiological paradox might partly be due to the low sensitivity of conventional MRI to detect gray matter demyelination. Magnetization transfer ratio (MTR) has previously been shown to detect white matter demyelination in mice. In this study, we investigated whether MTR can detect gray matter demyelination in cuprizone exposed mice. A total of 54 female C57BL/6 mice were split into one control group () and eight cuprizone exposed groups (). The mice were exposed to (w/w) cuprizone for up to six weeks. MTR images were obtained at a 7 Tesla Bruker MR-scanner before cuprizone exposure, weekly for six weeks during cuprizone exposure, and once two weeks after termination of cuprizone exposure. Immunohistochemistry staining for myelin (anti-Proteolopid Protein) and oligodendrocytes (anti-Neurite Outgrowth Inhibitor Protein A) was obtained after each weekly scanning. Rates of MTR change and correlations between MTR values and histological findings were calculated in five brain regions. In the corpus callosum and the deep gray matter a significant rate of MTR value decrease was found, per week () and per week () respectively. The MTR values correlated to myelin loss as evaluated by immunohistochemistry (Corpus callosum: . Deep gray matter: ), but did not correlate to oligodendrocyte density. Significant results were not found in the cerebellum, the olfactory bulb or the cerebral cortex. This study shows that MTR can be used to detect demyelination in the deep gray matter, which is of particular interest for imaging of patients with MS, as deep gray matter demyelination is common in MS, and is not easily detected on conventional clinical MRI.

Fjaer, Sveinung; B?, Lars; Lundervold, Arvid; Myhr, Kjell-Morten; Pavlin, Tina; Torkildsen, ?ivind; Wergeland, Stig

2013-01-01

366

ETR COMPLEX. CAMERA FACING SOUTH. FROM BOTTOM OF VIEW TO ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR COMPLEX. CAMERA FACING SOUTH. FROM BOTTOM OF VIEW TO TOP: MTR, MTR SERVICE BUILDING, ETR CRITICAL FACILITY, ETR CONTROL BUILDING (ATTACHED TO ETR), ETR BUILDING (HIGH-BAY), COMPRESSOR BUILDING (ATTACHED AT LEFT OF ETR), HEAT EXCHANGER BUILDING (JUST BEYOND COMPRESSOR BUILDING), COOLING TOWER PUMP HOUSE, COOLING TOWER. OTHER BUILDINGS ARE CONTRACTORS' CONSTRUCTION BUILDINGS. INL NEGATIVE NO. 56-4105. Unknown Photographer, ca. 1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

367

Transformation of Helicobacter pylori by chromosomal metronidazole resistance and by a plasmid with a selectable chloramphenicol resistance marker  

Microsoft Academic Search

per viable cell using a plate transformation procedure. Transformation of a metronidazole resistance marker (MtrR) was demonstrated when either a laboratory-derived mutant or a MtrR clinical isolate were used as the source of donor DNA. MtF was transformed at a frequency of 3 x per viable cell. All H. pylori strains tested produce large amounts of DNAase, which may reduce

YNG WANG; K. P. Roos; DIANE E. TAYLOR

1993-01-01

368

The Roles of Outer Membrane Cytochromes of Shewanella and Geobacter in Extracellular Electron Transfer  

Microsoft Academic Search

As key components of the electron transfer (ET) pathways used for dissimilatory reduction of solid iron [Fe(III)] and manganese [Mn(IV)] (hydr)oxides, outer membrane cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 and OmcE and OmcS of Geobacter sulfurreducens mediate ET reactions extracellularly. Cell surface-exposed MtrC and OmcA can transfer electrons directly to the metal oxides. S. oneidensis MR-1 cells also

Liang Shi; David J. Richardson; Zheming Wang; Sebastien N. Kerisit; Kevin M. Rosso; John M. Zachara; James K. Fredrickson

2009-01-01

369

Mapping cortical degeneration in ALS with magnetization transfer ratio and voxel-based morphometry.  

PubMed

Pathological and imaging data indicate that amyotrophic lateral sclerosis (ALS) is a multisystem disease involving several cerebral cortical areas. Advanced quantitative magnetic resonance imaging (MRI) techniques enable to explore in vivo the volume and microstructure of the cerebral cortex in ALS. We studied with a combined voxel-based morphometry (VBM) and magnetization transfer (MT) imaging approach the capability of MRI to identify the cortical areas affected by neurodegeneration in ALS patients. Eighteen ALS patients and 18 age-matched healthy controls were examined on a 1.5T scanner using a high-resolution 3D T1 weighted spoiled gradient recalled sequence with and without MT saturation pulse. A voxel-based analysis (VBA) was adopted in order to automatically compute the regional atrophy and MT ratio (MTr) changes of the entire cerebral cortex. By using a multimodal image analysis MTr was adjusted for local gray matter (GM) atrophy to investigate if MTr changes can be independent of atrophy of the cerebral cortex. VBA revealed several clusters of combined GM atrophy and MTr decrease in motor-related areas and extra-motor frontotemporal cortex. The multimodal image analysis identified areas of isolated MTr decrease in premotor and extra-motor frontotemporal areas. VBM and MTr are capable to detect the distribution of neurodegenerative alterations in the cortical GM of ALS patients, supporting the hypothesis of a multi-systemic involvement in ALS. MT imaging changes exist beyond volume loss in frontotemporal cortices. PMID:23874570

Cosottini, Mirco; Cecchi, Paolo; Piazza, Selina; Pesaresi, Ilaria; Fabbri, Serena; Diciotti, Stefano; Mascalchi, Mario; Siciliano, Gabriele; Bonuccelli, Ubaldo

2013-01-01

370

Mapping Cortical Degeneration in ALS with Magnetization Transfer Ratio and Voxel-Based Morphometry  

PubMed Central

Pathological and imaging data indicate that amyotrophic lateral sclerosis (ALS) is a multisystem disease involving several cerebral cortical areas. Advanced quantitative magnetic resonance imaging (MRI) techniques enable to explore in vivo the volume and microstructure of the cerebral cortex in ALS. We studied with a combined voxel-based morphometry (VBM) and magnetization transfer (MT) imaging approach the capability of MRI to identify the cortical areas affected by neurodegeneration in ALS patients. Eighteen ALS patients and 18 age-matched healthy controls were examined on a 1.5T scanner using a high-resolution 3D T1 weighted spoiled gradient recalled sequence with and without MT saturation pulse. A voxel-based analysis (VBA) was adopted in order to automatically compute the regional atrophy and MT ratio (MTr) changes of the entire cerebral cortex. By using a multimodal image analysis MTr was adjusted for local gray matter (GM) atrophy to investigate if MTr changes can be independent of atrophy of the cerebral cortex. VBA revealed several clusters of combined GM atrophy and MTr decrease in motor-related areas and extra-motor frontotemporal cortex. The multimodal image analysis identified areas of isolated MTr decrease in premotor and extra-motor frontotemporal areas. VBM and MTr are capable to detect the distribution of neurodegenerative alterations in the cortical GM of ALS patients, supporting the hypothesis of a multi-systemic involvement in ALS. MT imaging changes exist beyond volume loss in frontotemporal cortices.

Cosottini, Mirco; Cecchi, Paolo; Piazza, Selina; Pesaresi, Ilaria; Fabbri, Serena; Diciotti, Stefano; Mascalchi, Mario; Siciliano, Gabriele; Bonuccelli, Ubaldo

2013-01-01

371

Measurement of photon flux with a miniature gas ionization chamber in a Material Testing Reactor  

NASA Astrophysics Data System (ADS)

Nuclear heating measurements in Material Testing Reactors (MTR) are crucial for the design of the experimental devices and the prediction of the temperature of the hosted samples. Nuclear heating in MTR materials (except fuel) is mainly due to the energy deposition by the photon flux. Therefore, the photon flux is a key input parameter for the computer codes which simulate nuclear heating and temperature reached by samples/devices under irradiation. In the Jules Horowitz MTR under construction at the CEA Cadarache, the maximal expected nuclear heating levels will be about 15 to 18 W g-1 and it will be necessary to assess this parameter with the best accuracy. An experiment was performed at the OSIRIS reactor to combine neutron flux, photon flux and nuclear heating measurements to improve the knowledge of the nuclear heating in MTR. There are few appropriate sensors for selective measurement of the photon flux in MTR even if studies and developments are ongoing. An experiment, called CARMEN-1, was conducted at the OSIRIS MTR and we used in particular a gas ionization chamber based on miniature fission chamber design to measure the photon flux. In this paper, we detail Monte-Carlo simulations to analyze the photon fluxes with ionization chamber measurements and we compare the photon flux calculations to the nuclear heating measurements. These results show a good accordance between photon flux measurements and nuclear heating measurement and allow improving the knowledge of these parameters.

Fourmentel, D.; Filliatre, P.; Villard, J. F.; Lyoussi, A.; Reynard-Carette, C.; Carcreff, H.

2013-10-01

372

Folate Intake, MTHFR Polymorphisms, and the Risk of Colorectal Cancer: A Systematic Review and Meta-Analysis  

PubMed Central

Background. The objective was to determine whether relationships exist between the methylene-tetrahydrofolate reductase (MTHFR) polymorphisms and risk of colorectal cancer (CRC) and examine whether the risk is modified by level of folate intake. Methods. MEDLINE, Embase, and SCOPUS were searched to May 2012 using the terms “folic acid,” “folate,” “colorectal cancer,” “methylenetetrahydrofolate reductase,” “MTHFR.” Observational studies were included which (1) assessed the risk of CRC for each polymorphism and/or (2) had defined levels of folate intake for each polymorphism and assessed the risk of CRC. Results. From 910 references, 67 studies met our criteria; hand searching yielded 10 studies. The summary risk estimate comparing the 677CT versus CC genotype was 1.02 (95% CI 0.95–1.10) and for 677TT versus CC was 0.88 (95% CI 0.80–0.96) both with heterogeneity. The summary risk estimates for A1298C polymorphisms suggested no reduced risk. The summary risk estimate for high versus low total folate for the 677CC genotype was 0.70 (95% CI 0.56–0.89) and the 677TT genotype 0.63 (95% CI 0.41–0.97). Conclusion. These results suggest that the 677TT genotype is associated with a reduced risk of developing CRC, under conditions of high total folate intake, and this associated risk remains reduced for both MTHFR 677 CC and TT genotypes.

Kennedy, Deborah A.; Stern, Seth J.; Matok, Ilan; Moretti, Myla E.; Sarkar, Moumita; Adams-Webber, Thomasin; Koren, Gideon

2012-01-01

373

Variants of Folate Metabolism Genes and the Risk of Conotruncal Cardiac Defects  

PubMed Central

Background Although congenital heart defects (CHD) are the most common, serious group of birth defects, relatively little is known about the causes of these conditions and there are no established prevention strategies. There is evidence suggesting that the risk of CHD in general, and conotruncal and ventricular septal defects in particular, may be related to maternal folate status as well as genetic variants in folate-related genes. However, efforts to establish the relationships between these factors and CHD risk have been hampered by a number of factors including small study sample sizes and phenotypic heterogeneity. Methods and Results The present study examined the relationships between variation in nine folate-related genes and a subset of CHD phenotypes (i.e. conotruncal defects, perimembranous and malalignment type ventricular septal defects, and isolated aortic arch anomalies) in a cohort of over 700 case-parent triads. Further, both maternal and embryonic genetic effects were considered. Analyses of the study data confirmed a previously reported association between embryonic genotype for MTHFR A1298C and disease risk (unadjusted p=0.002). Conclusions These results represent the most comprehensive and powerful analysis of the relationship between CHD and folate-related genes reported to date, and provide additional evidence that, similar to neural tube defects, this subset of CHD is folate-related.

Goldmuntz, Elizabeth; Woyciechowski, Stacy; Renstrom, Daniel; Lupo, Philip J.; Mitchell, Laura E.

2011-01-01

374

Analysis and estimates of the attributable risk for environmental and genetic risk factors in gastric cancer in a Chinese population.  

PubMed

Development of gastric cancer is a multistage, multifactorial process. This study determined the population attributable risk for environmental and genetic risk factors in development of gastric cancer. A 1:1 cancer case-control study was undertaken in Nanjing, Jiangsu Province, China. A conditional-logistic regression model was used to determine environmental and genetic risk factors and calculate attributable risk (AR%) for each environmental and genetic risk factor in gastric cancer. In addition, the summary attributable risk (sAR) for all of the risk factors among 503 cases of gastric cancer patients and controls was determined. The environmental risk factors for gastric cancer in the Nanjing area were family history of tumor, consumption of pickled food, engorgement after hunger, irregular dietary habits, and lack of fruit intake. The genetic risk factors included the following genotypes: CYP2E1 wild, NAT2 M1 mutation, NAT2 slow-acetylators, XRCC1 194 mutation, MTHFR A1298C mutation, and IL-1B mutation. Combining environmental and genetic risk factors, sAR was 76.34%. Data suggest that genetic polymorphisms and environmental risk factors play concurrent roles in the development of gastric cancer. The results of this study indicate preventive strategies to avoid development of gastric cancer based on identified genetic polymorphisms and control of environmental risk factors. PMID:19492240

Shen, Xiaobing; Zhang, Jiao; Yan, Yingying; Yang, Yufeng; Fu, Gang; Pu, Yuepu

2009-01-01

375

Co-existence of renovascular hypertension, polyarteritis nodosa, antiphospholipid syndrome and methylenetetrahydrofolate reductase mutation.  

PubMed

We present a hypertensive child with a co-existence of polyarteritis nodosa, anti-phospholipid antibodies (aPL), methylenetetrahydrofolate reductase (MTHFR) mutation and increased lipoprotein a level. Elevated renin, aldosterone and aPL levels, micro-aneurysms, occlusion and thrombosis at left and right renal artery were found. Anti-hypertensive agents, prednisolone and pulse cyclophosphamide therapy were started and a stent was inserted in the left renal artery. Two months later, brain magnetic resonance imaging/magnetic resonance imaging angiography showed acute infarct area of the left parietofrontal lobe and middle cerebral artery stenosis. We found bilateral peripheral neuropathy, persistent aPL and elevated Lp(a) level and heterozygous A1298C/MTHFR mutation. Intravenous immunoglobulin and low-molecular-weight heparin treatment was added. In conclusion, our observation suggests that in patients with systemic vasculitis, such as polyarteritis nodosa, aPL are probably associated with greater thrombotic risks. The investigation of the LP(a) levels and MTHFR mutations as a synergic pro-coagulant effect might also be considered for determining patients with vasculitis at risk for severe thrombotic events. PMID:23910811

Yildiz, Bilal; Cetin, Nuran; Kural, Nurdan; Kaya, Tamer; Akcar, Nevbahar

2013-08-01

376

Synergistic activity of 5-trifluoromethylthioribose and inhibitors of methionine synthesis against Klebsiella pneumoniae.  

PubMed Central

5-Methylthioribose (MTR) is an intermediate in the methionine recycling pathway of organisms containing the enzyme MTR kinase. Analogs of MTR have been proposed as a new class of antimicrobial agents because of their ability to perturb the growth of MTR kinase-containing pathogens through inhibition of methionine salvage or by conversion to toxic products. One such analog, 5-trifluoromethylthioribose (TFMTR), has demonstrated potent inhibitory effects on the growth of Klebsiella pneumoniae (A. G. Gianotti, P. A. Tower, J. H. Sheley, P. A. Conte, C. Spiro, J. H. Fitchen, and M. K. Riscoe, J. Biol. Chem. 265:831-837, 1990). Although the mode of action of TFMTR has yet to be determined, it is believed that the drug is converted to the toxic products trifluoromethionine or carbonothioic difluoride via MTR kinase and the methionine recycling pathway. On the basis of this assumption, we theorized that blocking de novo methionine synthesis would increase dependence on the methionine salvage pathway and lead to an increased rate of synthesis of toxic metabolites from TFMTR. In this report, we show that three separate inhibitors of de novo methionine synthesis (1,2,4-triazole, azaserine, and propargylglycine) act synergistically with TFMTR in inhibiting the growth of K. pneumoniae.

Tower, P A; Johnson, L L; Ferro, A J; Fitchen, J H; Riscoe, M K

1991-01-01

377

Differentiation of Malignant and Benign Breast Lesions Using Magnetization Transfer Imaging and Dynamic Contrast-enhanced MRI  

PubMed Central

Purpose To evaluate feasibility of using magnetization transfer ratio (MTR) in conjunction with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for differentiation of benign and malignant breast lesions at 3 Tesla. Materials and Methods This prospective study was IRB and HIPAA compliant. DCE-MRI scans followed by MT imaging were performed on 41 patients. Region of interests (ROI’s) were drawn on co-registered MTR and DCE post-contrast images for breast structures, including benign lesions (BL) and malignant lesions (ML). Initial enhancement ratio (IER) and delayed enhancement ratio (DER) were calculated, as were normalized MTR, DER and IER (NMTR, NDER, NIER) values. Diagnostic accuracy analysis was performed. Results Mean MTR in ML was lower than in BL (p <0.05); mean DER and mean IER in ML were significantly higher than in BL (p<0.01, p<0.001). NMTR, NDER, and NIER were significantly lower in ML versus BL (p<0.007, p<0.001, p<0.001). IER had highest diagnostic accuracy (77.6%), sensitivity (86.2%), and area under the ROC curve (.879). MTR specificity was 100%. Logistic regression modeling with NMTR and NIER yielded best results for BL versus ML (sensitivity 93.1%, specificity 80%, AUC 0.884, accuracy 83.7%). Conclusion Isolated quantitative DCE analysis may increase specificity of breast MR for differentiating BL and ML. DCE-MRI with NMTR may produce a robust means of evaluating breast lesions.

Heller, Samantha L.; Moy, Linda; Lavianlivi, Sherlin; Moccaldi, Melanie; Kim, Sungheon

2013-01-01

378

[Differences between myofascial trigger points and tender points].  

PubMed

The article describes and compares the characteristics of myofascial trigger points (MTrPs) of the myofascial pain syndrome and the tender points (TePs) of the fibromyalgia syndrome. Many statements are hypothetical, because not all aspects of the disorders have been clarified in solid studies. Signs and symptoms of MTrPs: (1) palpable nodule, often located close to the muscle belly, (2) often single, (3) allodynia and hyperalgesia at the MTrP, (4) referral of the MTrP pain, (5) normal pain sensitivity outside the MTrPs, (6) local twitch response, (7) local contracture in biopsy material, (8) peripheral mechanism probable. Signs and symptoms of TePs: (1) no palpable nodule, (2) location often close to the muscle attachments, (3) multiple by definition, (4) allodynia and hyperalgesia also outside the TePs, (5) enhanced pain under psychic stress, (6) unspecific histological changes in biopsy material, (7) central nervous mechanism probable. The multitude of differences speak against a common aetiology and pathophysiology. PMID:21305384

Mense, S

2011-02-01

379

2?-O-ribose methylation of cap2 in human: function and evolution in a horizontally mobile family  

PubMed Central

The 5? cap of human messenger RNA consists of an inverted 7-methylguanosine linked to the first transcribed nucleotide by a unique 5?–5? triphosphate bond followed by 2?-O-ribose methylation of the first and often the second transcribed nucleotides, likely serving to modify efficiency of transcript processing, translation and stability. We report the validation of a human enzyme that methylates the ribose of the second transcribed nucleotide encoded by FTSJD1, henceforth renamed HMTR2 to reflect function. Purified recombinant hMTr2 protein transfers a methyl group from S-adenosylmethionine to the 2?-O-ribose of the second nucleotide of messenger RNA and small nuclear RNA. Neither N7 methylation of the guanosine cap nor 2?-O-ribose methylation of the first transcribed nucleotide are required for hMTr2, but the presence of cap1 methylation increases hMTr2 activity. The hMTr2 protein is distributed throughout the nucleus and cytosol, in contrast to the nuclear hMTr1. The details of how and why specific transcripts undergo modification with these ribose methylations remains to be elucidated. The 2?-O-ribose RNA cap methyltransferases are present in varying combinations in most eukaryotic and many viral genomes. With the capping enzymes in hand their biological purpose can be ascertained.

Werner, Maria; Purta, Elzbieta; Kaminska, Katarzyna H.; Cymerman, Iwona A.; Campbell, David A.; Mittra, Bidyottam; Zamudio, Jesse R.; Sturm, Nancy R.; Jaworski, Jacek; Bujnicki, Janusz M.

2011-01-01

380

A magnetization transfer imaging study of corpus callosum myelination in young children with autism  

PubMed Central

Background Several lines of evidence suggest that autism may be associated with abnormalities in white matter development. However, inconsistencies remain in the literature regarding the nature and extent of these abnormalities, partly due to the limited types of measurements that have been used. Here, we used Magnetization Transfer Imaging (MTI) to provide insight into the myelination of the corpus callosum in children with autism. Methods MTI scans were obtained in 101 children with autism and 35 typically developing children who did not significantly differ with regard to gender or age. The midsagittal area of the corpus callosum was manually traced and the magnetization transfer ratio (MTR) was calculated for each voxel within the corpus callosum. Mean MTR and height and location of the MTR histogram peak were analyzed. Results Mean MTR and MTR histogram peak height and location were significantly higher in children with autism than typically developing children, suggesting abnormal myelination of the corpus callosum in autism. Conclusions The differences in callosal myelination suggested by these results may reflect an alteration in the normally well-regulated process of myelination of the brain, with broad implications for neuropathology, diagnosis, and treatment of autism.

Gozzi, Marta; Nielson, Dylan M.; Lenroot, Rhoshel K.; Ostuni, John L.; Luckenbaugh, David A.; Thurm, Audrey E.; Giedd, Jay N.; Swedo, Susan E.

2012-01-01

381

Multi-Target Retrieval: The simultaneous retrieval of pressure, temperature andVolume Mixing Ratio profiles from limb-scanning atmospheric measurements  

NASA Astrophysics Data System (ADS)

A retrieval approach was developed for the simultaneous determination of the alt itude distributions of pressure (p), temperature (T) and Volume Mixing Ratio (VMR) of atmospheric constituents from limb scanning measurements of the atmosphere . This analysis method, named Multi-Target Retrieval (MTR), was designed and implemented in a computer code for the analysis of MIPAS-ENVISAT observations. However, the concepts implemented in MTR have a general validity and can be extended to the analysis of all types of limb-scanning observations. In order to assess performance and advantages of the proposed approach, MTR has been compared with the sequential analysis system implemented in the ESA's Level-2 processor for MIPAS measurements. The comparison was carried-out on a common set of target species and spectral intervals on simulated observations. The tests show that MTR produces results of better quality than a sequential retrieval. The preliminary results of the analysis of real MIPAS data and the advantages of the MTR analysis system in terms of systematic errors will also be presented.

Dinelli, B. M.; Alpaslan, D.; Carlotti, M.; Magnani, L.; Prevedelli, M.; Ridolfi, M.

2003-04-01

382

A revised description of graphite irradiation induced creep  

NASA Astrophysics Data System (ADS)

The UK fleet of advanced gas-cooled reactors (AGR) have been operating for a substantial period of time and rely on data obtained from material test reactor (MTR) programs, dating back to the 1960s and through to the end of the 1980s, to support current and future operation. Historically an empirical approach to the irradiation behaviour of graphite has been used and, due to the nature of the available MTR data and the lack of a consistent set of data containing all the relevant measurements, this is still largely the case at present. Differences in interpretation of the available MTR data can have a significant impact on the assessed integrity of core components. Consequently, a thorough review of the basis of the current models is being carried out, and new models are being developed as necessary. This paper presents some new interpretations of the available low fluence MTR data for irradiation creep and application of a revised model to some high fluence MTR data.

Davies, Mark A.; Bradford, Mark

2008-10-01

383

Trypanosoma brucei spliced leader RNA maturation by the cap 1 2'-O-ribose methyltransferase and SLA1 H/ACA snoRNA pseudouridine synthase complex.  

PubMed

Kinetoplastid flagellates attach a 39-nucleotide spliced leader (SL) upstream of protein-coding regions in polycistronic RNA precursors through trans splicing. SL modifications include cap 2'-O-ribose methylation of the first four nucleotides and pseudouridine (psi) formation at uracil 28. In Trypanosoma brucei, TbMTr1 performs 2'-O-ribose methylation of the first transcribed nucleotide, or cap 1. We report the characterization of an SL RNA processing complex with TbMTr1 and the SLA1 H/ACA small nucleolar ribonucleoprotein (snoRNP) particle that guides SL psi(28) formation. TbMTr1 is in a high-molecular-weight complex containing the four conserved core proteins of H/ACA snoRNPs, a kinetoplastid-specific protein designated methyltransferase-associated protein (TbMTAP), and the SLA1 snoRNA. TbMTAP-null lines are viable but have decreased SL RNA processing efficiency in cap methylation, 3'-end maturation, and psi(28) formation. TbMTAP is required for association between TbMTr1 and the SLA1 snoRNP but does not affect U1 small nuclear RNA methylation. A complex methylation profile in the mRNA population of TbMTAP-null lines indicates an additional effect on cap 4 methylations. The TbMTr1 complex specializes the SLA1 H/ACA snoRNP for efficient processing of multiple modifications on the SL RNA substrate. PMID:19103757

Zamudio, Jesse R; Mittra, Bidyottam; Chattopadhyay, Arnab; Wohlschlegel, James A; Sturm, Nancy R; Campbell, David A

2009-03-01

384

5'-Methylthioadenosine Nucleosidase and 5-Methylthioribose Kinase Activities and Ethylene Production during Tomato Fruit Development and Ripening.  

PubMed

5'-Methylthioadenosine (MTA) nucleosidase and 5-methylthioribose (MTR) kinase activities were measured in crude extracts of tomato fruits (Lycopersicon esculentum Mill cv Rutgers) during fruit development and ripening. The highest activity of MTA nucleosidase (1.2 nanomoles per milligram protein per minute) was observed in small green fruits. The activity decreased during ripening; at the overripe stage only 6.5% of the peak activity remained. MTR kinase activity was low at the small green stage and increased thereafter until it reached peak activity at the breaker stage (0.7 nanomoles per milligram protein per minute) followed by a sharp decline at the later stages of fruit ripening. 1-Amino-cyclopropane-1-carboxylic acid (ACC) levels peaked at the red stage, while ethylene reached its highest level at the light-red stage. Several analogs of MTA and MTR were tested as both enzyme and ethylene inhibitors. Of the MTA analogs examined for their ability to inhibit MTA nucleosidase, 5'-chloroformycin reduced enzyme activity 89%, whereas 5'-chloroadenosine, 5'-isobutylthioadenosine, 5'-isopropylthioadenosine, and 5'-ethylthioadenosine inhibited the reaction with MTA by about 40%. 5'-Chloroformycin and 5'-chloroadenosine inhibited ethylene production over a period of 24 hours by about 64 and 42%, respectively. Other analogs of MTA were not effective inhibitors of ethylene production, whereas aminoethoxyvinylglycine showed a 34% inhibition over the same period of time. Of the MTR analogs tested, 5-isobutylthioribose was the most effective inhibitor of both MTR-kinase (41%) and ethylene production (35%). PMID:16664444

Kushad, M M; Richardson, D G; Ferro, A J

1985-10-01

385

Links between dwarf and classical novae, and implications for the space densities and evolution of cataclysmic binaries  

SciTech Connect

The effects of mass and angular momentum losses during a nova eruption are investigated by simulation in the context of a new nova evolution model. It is argued that surveys for cataclysmic variables (CVs) are very incomplete and that the local space density of CVs could well be 0.0001/cu pc. It is shown that the competing effets of mass and angular momentum loss usually increase the separation of a red and white dwarf during a nova eruption. The reasons why old novae remain bright for about a century after eruption and why they reduce the mass transfer rate (MTR) and eventually go into a state of hibernation for a thousand to a million years, eventually reviving as dwarf novae or novalike variables, are discussed. The results of these simulations are used to demonstrate the consistency of variable MTR in resolving the MTR discrepancy. 43 references.

Shara, M.M.; Livio, M.; Moffat, A.F.J.; Orio, M.

1986-12-01

386

Measuring the Elongational Properties of Polymer Melts-a Simple Task?  

NASA Astrophysics Data System (ADS)

Elongational flow measurements were performed on a number of samples under similar conditions using two different elongational rheometers, a Münstedt type oil bath rheometer (MTR) and the elongational viscosity fixture (EVF) of TA Instruments in an ARES rheometer. Deviations of several degrees from the set temperature are found in the case of the EVF/ARES and had to be corrected before comparing results. Inhomogeneous deformation, e.g. due to sagging, leads to an artificial strain-hardening of the EVF. For strain-hardening and/or high viscous materials a good agreement between measurements from both rheometers is found. The strain hardening measured in the EVF/ARES starts at smaller strains compared the MTR. This effect is more pronounced for weakly strain-hardening materials. The possibility of creep and creep-recovery experiments performed by the MTR demonstrates its wide application range.

Kaschta, Joachim; Münstedt, Helmut

2008-07-01

387

Trap states and transport characteristics in picene thin film field-effect transistor  

NASA Astrophysics Data System (ADS)

Transport characteristics and trap states are investigated in picene thin film field-effect transistor under O2 atmosphere on the basis of multiple shallow trap and release (MTR) model. The channel transport is dominated by MTR below 300 K. It has been clarified on the basis of MTR model that the O2-exposure induces a drastic reduction in shallow trap density to increase both the field-effect mobility ? and on-off ratio. We also found that the O2-exposure never caused an increase in hole carrier density. Actually, a very high ? value of 3.2 cm2 V-1 s-1 is realized under 500 Torr of O2.

Kawasaki, Naoko; Kubozono, Yoshihiro; Okamoto, Hideki; Fujiwara, Akihiko; Yamaji, Minoru

2009-01-01

388

Surface-based analysis reveals regions of reduced cortical magnetization transfer ratio in patients with multiple sclerosis: A proposed method for imaging subpial demyelination.  

PubMed

The in vivo detection of subpial cortical gray matter lesions in multiple sclerosis is challenging. We quantified the spatial extent of subpial decreases in the magnetization transfer ratio (MTR) of cortical gray matter in subjects with multiple sclerosis, as such reductions may indicate regions of cortical demyelination. We exploited the unique geometry of cortical lesions by using two-dimensional parametric surface models of the cortex instead of traditional three-dimensional voxel-wise analyses. MTR images were mapped onto intermediate surfaces between the pial and white matter surfaces and were used to compute differences between secondary-progressive MS (n = 12), relapsing-remitting MS (n = 12), and normal control (n = 12) groups as well as between each individual patient and the normal controls. We identified large regions of significantly reduced cortical MTR in secondary-progressive patients when compared with normal controls. We also identified large regions of reduced cortical MTR in 11 individual patients (8 secondary-progressive, 3 relapsing-remitting). The secondary-progressive patients showed larger areas of abnormally low MTR compared with relapsing-remitting patients both at the group level and on an individual basis. The spatial distributions of abnormal MTR preferentially involved cingulate cortex, insula, and the depths of sulci, in agreement with pathological descriptions of subpial gray matter lesion distribution. These findings suggest that our method is a plausible in vivo imaging technique for quantifying subpial cortical demyelinating lesions in patients with multiple sclerosis and, furthermore, can be applied at the typical clinical field strength of 1.5 T. Hum Brain Mapp 35:3402-3413, 2014. © 2013 Wiley Periodicals, Inc. PMID:24356893

Derakhshan, Mishkin; Caramanos, Zografos; Narayanan, Sridar; Arnold, Douglas L; Louis Collins, D

2014-07-01

389

Possible Dynamically Gated Conductance along Heme Wires in Bacterial Multiheme Cytochromes.  

PubMed

The staggered cross decaheme configuration of electron transfer cofactors in the outer-membrane cytochrome MtrF serves as a prototype for conformationally gated multiheme electron transport. Derived from the bacterium Shewanella oneidensis, the staggered cross configuration reveals intersecting c-type octaheme and tetraheme "wires" containing thermodynamic "hills" and "valleys" (Proc. Natl. Acad. Sci. U. S. A. 2014, 11, 611-616), suggesting that the protein structure may include a dynamical mechanism for conductance and pathway switching depending on enzymatic functional need. Here, we applied classical molecular and statistical mechanics calculations of large-amplitude protein dynamics in MtrF, to address its potential to modulate pathway conductance, including assessment of the effect of the total charge state. Explicit solvent molecular dynamics simulations of fully oxidized and fully reduced MtrF showed that the slowest mode of collective decaheme motion is 90% similar between the oxidized and reduced states and consists primarily of interheme separation with minor rotational contributions. The frequency of this motion is 1.7 × 10(7) s(-1), both for fully oxidized and fully reduced MtrF, slower than the downhill electron transfer rates between stacked heme pairs at the octaheme termini and faster than the electron transfer rates between parallel hemes in the tetraheme chain. This implies that MtrF uses slow conformational fluctuations to modulate electron flow along the octaheme pathway, apparently for the purpose of increasing the residence time of electrons on lowest potential hemes 4 and 9. This apparent gating mechanism should increase the success rate of electron transfer from MtrF to low potential environmental acceptors via these two solvent-exposed hemes. PMID:24975678

Smith, Dayle M A; Rosso, Kevin M

2014-07-24

390

Cationic Antimicrobial Peptide Resistance in Neisseria meningitidis  

PubMed Central

Cationic antimicrobial peptides (CAMPs) are important components of the innate host defense system against microbial infections and microbial products. However, the human pathogen Neisseria meningitidis is intrinsically highly resistant to CAMPs, such as polymyxin B (PxB) (MIC ? 512 ?g/ml). To ascertain the mechanisms by which meningococci resist PxB, mutants that displayed increased sensitivity (?4-fold) to PxB were identified from a library of mariner transposon mutants generated in a meningococcal strain, NMB. Surprisingly, more than half of the initial PxB-sensitive mutants had insertions within the mtrCDE operon, which encodes proteins forming a multidrug efflux pump. Additional PxB-sensitive mariner mutants were identified from a second round of transposon mutagenesis performed in an mtr efflux pump-deficient background. Further, a mutation in lptA, the phosphoethanolamine (PEA) transferase responsible for modification of the lipid A head groups, was identified to cause the highest sensitivity to PxB. Mutations within the mtrD or lptA genes also increased meningococcal susceptibility to two structurally unrelated CAMPs, human LL-37 and protegrin-1. Consistently, PxB neutralized inflammatory responses elicited by the lptA mutant lipooligosaccharide more efficiently than those induced by wild-type lipooligosaccharide. mariner mutants with increased resistance to PxB were also identified in NMB background and found to contain insertions within the pilMNOPQ operon involved in pilin biogenesis. Taken together, these data indicated that meningococci utilize multiple mechanisms including the action of the MtrC-MtrD-MtrE efflux pump and lipid A modification as well as the type IV pilin secretion system to modulate levels of CAMP resistance. The modification of meningococcal lipid A head groups with PEA also prevents neutralization of the biological effects of endotoxin by CAMP.

Tzeng, Yih-Ling; Ambrose, Karita D.; Zughaier, Susu; Zhou, Xiaoliu; Miller, Yoon K.; Shafer, William M.; Stephens, David S.

2005-01-01

391

Migraineurs without aura show microstructural abnormalities in the cerebellum and frontal lobe.  

PubMed

The involvement of the cerebellum in migraine pathophysiology is not well understood. We used a biparametric approach at high-field MRI (3 T) to assess the structural integrity of the cerebellum in 15 migraineurs with aura (MWA), 23 migraineurs without aura (MWoA), and 20 healthy controls (HC). High-resolution T1 relaxation maps were acquired together with magnetization transfer images in order to probe microstructural and myelin integrity. Clusterwise analysis was performed on T1 and magnetization transfer ratio (MTR) maps of the cerebellum of MWA, MWoA, and HC using an ANOVA and a non-parametric clusterwise permutation F test, with age and gender as covariates and correction for familywise error rate. In addition, mean MTR and T1 in frontal regions known to be highly connected to the cerebellum were computed. Clusterwise comparison among groups showed a cluster of lower MTR in the right Crus I of MWoA patients vs. HC and MWA subjects (p?=?0.04). Univariate and bivariate analysis on T1 and MTR contrasts showed that MWoA patients had longer T1 and lower MTR in the right and left pars orbitalis compared to MWA (p?MTR and longer T1 point at a loss of macromolecules and/or micro-edema in Crus I and pars orbitalis in MWoA patients vs. HC and vs. MWA. The pathophysiological implications of these findings are discussed in light of recent literature. PMID:23703313

Granziera, C; Romascano, D; Daducci, A; Roche, A; Vincent, M; Krueger, G; Hadjikhani, N

2013-12-01

392

Age independently affects myelin integrity as detected by magnetization transfer magnetic resonance imaging in multiple sclerosis  

PubMed Central

Background Multiple sclerosis (MS) is a heterogeneous disorder with a progressive course that is difficult to predict on a case-by-case basis. Natural history studies of MS have demonstrated that age influences clinical progression independent of disease duration. Objective To determine whether age would be associated with greater CNS injury as detected by magnetization transfer MRI. Materials and methods Forty MS patients were recruited from out-patient clinics into two groups stratified by age but with similar clinical disease duration as well as thirteen controls age-matched to the older MS group. Images were segmented by automated programs and blinded readers into normal appearing white matter (NAWM), normal appearing gray matter (NAGM), and white matter lesions (WMLs) and gray matter lesions (GMLs) in the MS groups. WML and GML were delineated on T2-weighted 3D fluid-attenuated inversion recovery (FLAIR) and T1 weighted MRI volumes. Mean magnetization transfer ratio (MTR), region volume, as well as MTR histogram skew and kurtosis were calculated for each region. Results All MTR measures in NAGM and MTR histogram metrics in NAWM differed between MS subjects and controls, as expected and previously reported by several studies, but not between MS groups. However, MTR measures in the WML did significantly differ between the MS groups, in spite of no significant differences in lesion counts and volumes. Conclusions Despite matching for clinical disease duration and recording no significant WML volume difference, we demonstrated strong MTR differences in WMLs between younger and older MS patients. These data suggest that aging-related processes modify the tissue response to inflammatory injury and its clinical outcome correlates in MS.

Newbould, R.D.; Nicholas, R.; Thomas, C.L.; Quest, R.; Lee, J.S.Z.; Honeyfield, L.; Colasanti, A.; Malik, O.; Mattoscio, M.; Matthews, P.M.; Sormani, M.P.; Waldman, A.D.; Muraro, P.A.

2014-01-01

393

Treatment of myofascial trigger points in patients with chronic shoulder pain: a randomized, controlled trial  

PubMed Central

Background Shoulder pain is a common musculoskeletal problem that is often chronic or recurrent. Myofascial trigger points (MTrPs) cause shoulder pain and are prevalent in patients with shoulder pain. However, few studies have focused on MTrP therapy. The aim of this study was to assess the effectiveness of multimodal treatment of MTrPs in patients with chronic shoulder pain. Methods A single-assessor, blinded, randomized, controlled trial was conducted. The intervention group received comprehensive treatment once weekly consisting of manual compression of the MTrPs, manual stretching of the muscles and intermittent cold application with stretching. Patients were instructed to perform muscle-stretching and relaxation exercises at home and received ergonomic recommendations and advice to assume and maintain good posture. The control group remained on the waiting list for 3 months. The Disabilities of Arm, Shoulder and Hand (DASH) questionnaire score (primary outcome), Visual Analogue Scale for Pain (VAS-P), Global Perceived Effect (GPE) scale and the number of muscles with MTrPs were assessed at 6 and 12 weeks in the intervention group and compared with those of a control group. Results Compared with the control group, the intervention group showed significant improvement (P < 0.05) on the DASH after 12 weeks (mean difference, 7.7; 95% confidence interval (95% CI), 1.2 to 14.2), on the VAS-P1 for current pain (mean difference, 13.8; 95% CI, 2.6 to 25.0), on the VAS-P2 for pain in the past 7 days (mean difference, 10.2; 95% CI, 0.7 to 19.7) and VAS-P3 most severe pain in the past 7 days (mean difference, 13.8; 95% CI, 0.8 to 28.4). After 12 weeks, 55% of the patients in the intervention group reported improvement (from slightly improved to completely recovered) versus 14% in the control group. The mean number of muscles with active MTrPs decreased in the intervention group compared with the control group (mean difference, 2.7; 95% CI, 1.2 to 4.2). Conclusions The results of this study show that 12-week comprehensive treatment of MTrPs in shoulder muscles reduces the number of muscles with active MTrPs and is effective in reducing symptoms and improving shoulder function in patients with chronic shoulder pain. Trial registration number ISRCTN: ISRCTN75722066

2011-01-01

394

HOT CELL BUILDING, TRA632. CONTEXTUAL AERIAL VIEW OF HOT CELL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. CONTEXTUAL AERIAL VIEW OF HOT CELL BUILDING, IN VIEW AT LEFT, AS YET WITHOUT ROOF. PLUG STORAGE BUILDING LIES BETWEEN IT AND THE SOUTH SIDE OF THE MTR BUILDING AND ITS WING. NOTE CONCRETE DRIVE BETWEEN ROLL-UP DOOR IN MTR BUILDING AND CHARGING FACE OF PLUG STORAGE. REACTOR SERVICES BUILDING (TRA-635) WILL COVER THIS DRIVE AND BUTT UP TO CHARGING FACE. DOTTED LINE IS ON ORIGINAL NEGATIVE. TRA PARKING LOT IN LEFT CORNER OF THE VIEW. CAMERA FACING NORTHWESTERLY. INL NEGATIVE NO. 8274. Unknown Photographer, 7/2/1953 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

395

Human Cytomegalovirus and Human Herpesvirus 6 Genes That Transform and Transactivate  

PubMed Central

This review is an update on the transforming genes of human cytomegalovirus (HCMV) and human herpesvirus 6 (HHV-6). Both viruses have been implicated in the etiology of several human cancers. In particular, HCMV has been associated with cervical carcinoma and adenocarcinomas of the prostate and colon. In vitro transformation studies have established three HCMV morphologic transforming regions (mtr), i.e., mtrI, mtrII, and mtrIII. Of these, only mtrII (UL111A) is retained and expressed in both transformed and tumor-derived cells. The transforming and tumorigenic activities of the mtrII oncogene were localized to an open reading frame (ORF) encoding a 79-amino-acid (aa) protein. Furthermore, mtrII protein bound to the tumor suppressor protein p53 and inhibited its ability to transactivate a p53-responsive promoter. In additional studies, the HCMV immediate-early protein IE86 (IE2; UL122) was found to interact with cell cycle-regulatory proteins such as p53 and Rb. However, IE86 exhibited transforming activity in vitro only in cooperation with adenovirus E1A. HHV-6 is a T-cell-tropic virus associated with AIDS-related and other lymphoid malignancies. In vitro studies identified three transforming fragments, i.e., SalI-L, ZVB70, and ZVH14. Of these, only SalI-L (DR7) was retained in transformed and tumor-derived cells. The transforming and tumorigenic activities of SalI-L have been localized to a 357-aa ORF-1 protein. The ORF-1 protein was expressed in transformed cells and, like HCMV mtrII, bound to p53 and inhibited its ability to transactivate a p53-responsive promoter. HHV-6 has also been proposed to be a cofactor in AIDS because both HHV-6 and human immunodeficiency virus type 1 (HIV-1) have been demonstrated to coinfect human CD4+ T cells, causing accelerated cytopathic effects. Interestingly, like the transforming proteins of DNA tumor viruses such as simian virus 40 and adenovirus, ORF-1 was also a transactivator and specifically up-regulated the HIV-1 long terminal repeat when cotransfected into CD4+ T cells. Finally, based on the interactions of HCMV and HHV-6 transforming proteins with tumor suppressor proteins, a scheme is proposed for their role in oncogenesis.

Doniger, Jay; Muralidhar, Sumitra; Rosenthal, Leonard J.

1999-01-01

396

FAST CHOPPER DETECTOR HOUSE, TRA665. FIRST FLOOR, PLAN AND SECTION, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FAST CHOPPER DETECTOR HOUSE, TRA-665. FIRST FLOOR, PLAN AND SECTION, AS PROPOSED FOR MODIFICATION IN 1962. CONCRETE WALLS THREE FEET THICK. EXISTING WINDOWS IN MTR AND DETECTOR HOUSE WALLS WERE TO BE FILLED IN WITH HIGH-DENSITY BRICK. NOTE 20-METER MARK, WHERE THE FAST CHOPPER DETECTOR HAD BEEN LOCATED. F.C. TORKELSON 842-MTR-665-S-2, 4/1962. INL INDEX NO. 531-0665-60-851-150996, REV. 5. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

397

PROCESS WATER BUILDING, TRA605. AERIAL TAKEN WHILE SEVERAL PIPE TRENCHES ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PROCESS WATER BUILDING, TRA-605. AERIAL TAKEN WHILE SEVERAL PIPE TRENCHES REMAINED OPEN. CAMERA FACES EASTERLY. NOTE DUAL PIPES BETWEEN REACTOR BUILDING AND NORTH SIDE OF PROCESS WATER BUILDING. PIPING NEAR WORKING RESERVOIR HEADS FOR RETENTION RESERVOIR. PIPE FROM DEMINERALIZER ENTERS MTR FROM NORTH. SEE ALSO TRENCH FOR COOLANT AIR DUCT AT SOUTH SIDE OF MTR AND LEADING TO FAN HOUSE AND STACK. INL NEGATIVE NO. 2966-A. Unknown Photographer, 7/31/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

398

Solar spectropolarimetry with THEMIS  

NASA Astrophysics Data System (ADS)

We report spectropolarimetric observations with THEMIS telescope multi-lines operating mode (MTR) during the last campaigns. We demonstrate the very favorable performances of THEMIS for investigations of the magnetic field and we report also observations devoted to the measurement of the scattering polarization. In that case, the signals are weak and are not “a priori" included in the THEMIS objectives but results show that THEMIS is a suitable instrument not only for strong field at high spatial resolution but also for weak signal at high polarimetric sensitivity. We describe briefly the multi-line spectropolarimetry mode (MTR) available at the franco-italian solar telescope THEMIS.

Molodij, G.; Rayrole, J.

399

Development of a core follow calculational system for research reactors  

SciTech Connect

Over the last few years a comprehensive PWR and MTR core analysis code system based on modern reactor physics methods has been under development by the Atomic Energy Corporation of South Africa. This system, known as OSCAR-3, will incorporate a customized graphical user interface and data management system to ensure user-friendliness and good quality control. The system has now reached the stage of development where it can be used for practical MTR core analyses. This paper describes the current capabilities of the components of the OSCAR-3 package, their integration within the package, and outlines future developments.

Mueller, E.Z.; Ball, G.; Joubert, W.R. [and others

1994-12-31

400

Combined folate gene MTHFD and TC polymorphisms as maternal risk factors for Down syndrome in China.  

PubMed

We examined whether polymorphisms in the methylenetetrahydrofolate dehydrogenase (MTHFD) and transcobalamin (TC) genes, which are involved in folate metabolism, affect maternal risk for Down syndrome. We investigated 76 Down syndrome mothers and 115 control mothers from Bengbu, China. Genomic DNA was isolated from the peripheral lymphocytes. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFD G1958A and TC C776G. The frequencies of the polymorphic alleles were 24.3 and 19.1% for MTHFD 1958A, 53.9 and 54.2% for TC 776G, in the case and control groups, respectively. No significant differences were found between two groups in relation to either the allele or the genotype frequency for both polymorphisms. However, when gene-gene interactions between these two polymorphisms together with previous studied C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene were analyzed, the combined MTHFR 677CT/TT and MTHFD 1958AA/GA genotype was found to be significantly associated with the risk of having a Down syndrome child [odds ratio (OR) = 3.11; 95% confidence interval (95%CI) = 1.07-9.02]. In addition, the combined TC 776CG and MTHFR 677TT genotype increased the risk of having a child with Down syndrome 3.64-fold (OR = 3.64; 95%CI = 1.28-10.31). In conclusion, neither MTHFD G1958A nor TC C776G polymorphisms are an independent risk factor for Down syndrome. However, the combined MTHFD/MTHFR, TC/MTHFR genotypes play a role in the risk of bearing a Down syndrome child in the Chinese population. PMID:24668664

Liao, Y P; Zhang, D; Zhou, W; Meng, F M; Bao, M S; Xiang, P; Liu, C Q

2014-01-01

401

A case-control nutrigenomic study on the synergistic activity of folate and vitamin B12 in cervical cancer progression.  

PubMed

The present study was designed to identify the role of folate, B12, homocysteine, and polymorphisms of methylene tetrahydrofolatereductase (MTHFR) gene in cervical carcinogenesis among 322 women from Kerala, South India. Serum folate, vitamin B12 (chemiluminescence assay), and homocysteine (EIA) along with genetic polymorphisms of MTHFR gene (polymerase chain reaction/restriction fragment length polymorphism) were analyzed for 136 control subjects, 92 low-grade squamous intraepithelial lesions (LSIL) subjects, and 94 invasive cervical cancer cases (ICC). Statistically significant associations between MTHFR polymorphisms, serum homocysteine, and folate levels with cervical carcinogenesis were not evident, but we found that these parameters acted as effect modifiers of serum vitamin B12. The risk estimates observed for B12 became prominent only when there was a deficiency in serum folate levels [LSIL-odds ratio (OR): 14.9 (95% CI: 2.65 to 84.4); ICC-OR = 8.72 (95% CI = 1.55 to 48.8)] or when MTHFR A1298C polymorphic variant was present [LSIL-OR = 9.8 (95% CI = 2.61 to 36.7); ICC-OR = 10.0 (95%CI = 2.5 to 39.3)]. The statistical significance of this effect modification was further studied using an interaction model, where only folate was observed to have an influence on B12 levels as suggested by the odds ratio of 7.11 (95% CI = 0.45 to 111.9) obtained for ICC group, implicating a synergistic role of these 2 vitamins in invasive cervical cancer. PMID:22519865

Ragasudha, Preethi N; Thulaseedharan, Jissa V; Wesley, Ramani; Jayaprakash, P G; Lalitha, Prema; Pillai, M Radhakrishna

2012-01-01

402

Investigation of inherited thrombophilias in patients with pulmonary embolism.  

PubMed

Inherited thrombophilias are thought to play an important role in the cause of pulmonary embolism and its recurrence. Ninety of 281 patients objectively diagnosed as pulmonary embolism between 2006 and 2009 were included in the study. The screening for thrombophilia included mutations of factor V Leiden (FVL), prothrombin (PTM) G20210A, methylene tetrahydrofolate reductase C677T-A1298C, the serum levels of antithrombin III, protein C, protein S, factor VIII and activated protein C resistance. Forty-two male (46.7%) and 48 female (53.3%) patients had a mean age of 62.6?±?13.4 years. Patients with common thrombophilias comprised 30% of all cases (FVL: 19.1%, PTM G20210A: 3.4%, antithrombin III deficiency: 1.1%, protein C deficiency: 5.7%, protein S deficiency: 13.6%). A significant association between recurrence of pulmonary embolism (10 patients, 12.2%) and protein S deficiency was established (P?=?0.040). Serum level of protein C was also significantly lower in the subgroup of recurrent pulmonary embolism (P?=?0.049). FVL and PTM mutations were high in cancer patients; the presence of inherited thrombophilia was low with risk factors of surgery and immobilization. Genetic risk factors were high in patients with pulmonary embolism. Protein C and S deficiencies may play a role in pulmonary embolism recurrence. DVT or family history of pulmonary embolism was not found to be related to inherited thrombophilias. Surgery and immobilization were thought not to have priorities for detection of genetic risk factors. The high percentages of FVL and PTM mutations in cancer patients should be considered. PMID:23358198

Turan, Onur; Ündar, Bülent; Günay, Türkan; Akkoçlu, Atila

2013-03-01

403

Green tea intake, MTHFR/TYMS genotype and breast cancer risk: the Singapore Chinese Health Study  

PubMed Central

The tea polyphenol (?)-epigallocatechin-3-gallate (EGCG) has been reported to act as a cancer preventive agent through folate pathway inhibition in experimental studies. We hypothesized that if folate pathway inhibition is the mechanism of cancer preventive activities of EGCG, then the protective effect against breast cancer would be stronger among women with low dietary folate intake and the high-activity methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TYMS) genotypes. In a nested case–control study of 380 women with incident breast cancer and 662 controls within the Singapore Chinese Health Study, we found no association between either green tea intake or gene polymorphisms of MTHFR (C677T and A1298C) and TYMS (1494 ins/del) and breast cancer risk. However, among women with low folate intake (<133.4 ?g/day), weekly/daily green tea intake was inversely associated with breast cancer risk compared with less green tea intake [odds ratio (OR) = 0.45, 95% confidence interval (CI) = 0.26–0.79, P for interaction = 0.02]. Among women with high folate intake (?133.4 ?g/day), green tea intake was not associated with breast cancer. Similarly, among women possessing the high-activity MTHFR/TYMS genotypes (0–1 variant allele), weekly/daily versus less frequent green tea intake was associated with lower breast cancer risk (OR?=?0.66, 95% CI?=?0.45–0.98), which was observed even more strongly among those who also had low folate intake (OR?=?0.44, 95% CI?=?0.22–0.89) than high folate intake (OR?=?0.92, 95% CI?=?0.55–1.54). This association was not observed among women possessing the low-activity genotypes (2–4 variant alleles). Our findings suggest that folate pathway inhibition may be one mechanism through which green tea protects against breast cancer in humans.

Inoue, Maki; Robien, Kim; Wang, Renwei; Van Den Berg, David J.; Koh, Woon-Puay; Yu, Mimi C.

2008-01-01

404

A novel mutation in the complement regulator clusterin in recurrent hemolytic uremic syndrome.  

PubMed

A novel heterozygous mutation in the clusterin gene, nucleotide position A1298C (glutamine>proline Q433P), was detected in exon 7 of a child with recurrent hemolytic uremic syndrome (HUS). The same mutation was found in the child's two siblings and mother but not in 120 controls. In addition, a previously described heterozygous mutation was detected in the gene encoding membrane cofactor protein (MCP) causing a 6 base-pair deletion 811-816delGACAGT in exon 6. It was found in the patient, both siblings and the father. One sibling had recovered from post-streptococcal glomerulonephritis. Clusterin levels in the patient, siblings and parents were normal as was the migration pattern in a gel. Patient serum induced C3 and C9 deposition on normal washed platelets, and platelet activation, as detected by flow cytometry. The same phenomenon was found in serum taken from the siblings and the mother but not in the sample from the father and controls. Addition of clusterin to patient serum did not inhibit complement activation on platelets. The Q433P mutant, in isolated form, was further studied by binding to the components of the terminal complement complex. The mutant did not bind to C5b-7 that was immobilized onto a BIAcore chip, whereas wild-type clusterin did, indicating that the mutation could lead to defective inhibition of formation of the membrane attack complex under these conditions. Hemolysis of rabbit erythrocytes was inhibited by wild-type clusterin but not by the mutant. Mutated clusterin could thus not prevent assembly of the membrane attack complex on platelets and erythrocytes. PMID:19446882

Ståhl, Anne-lie; Kristoffersson, AnnCharlotte; Olin, Anders I; Olsson, Martin L; Roodhooft, Anne-Marie; Proesmans, Willem; Karpman, Diana

2009-07-01

405

Multiple cerebral sinus thromboses complicating meningococcal meningitis: a pediatric case report  

PubMed Central

Background Cerebral venous sinus thrombosis (CVT) is a rare and potentially life-threatening condition in the pediatric population. The clinical presentation is frequently nonspecific; thus diagnosis is often delayed or missed. Case presentation A previously healthy 8 month-old boy was diagnosed with meningococcal meningitis. At hospital admission, an urgent non contrast-enhanced computed tomography (CT) of the head and neck was performed with normal results. Ceftriaxone was promptly started and the clinical condition of the patient improved. However, on the 7th day of hospitalization, the child suddenly manifested irritability and lethargy. An urgent contrast-enhanced CT of the head and neck was immediately performed, revealing thrombosis of the superior sagittal, transverse and rectus sinuses. A thrombophilic evaluation was performed, revealing hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR) variants (C677T and A1298C). Conclusions The causes of CVT may be categorized into three main groups: hypercoagulable states, conditions causing blood flow disturbances, and all causes of inflammation or infection. In this case report, we observed more than one risk factor that predisposed the patient to CVT. Consequently, even if a causative factor is detected, a thrombophilic blood evaluation should be performed. In fact, in case of a prothrombotic condition, the patient’s family should be advised that prompt administration of anticoagulant is necessary in the event of situations that could lead to thrombosis. Finally, CVT may be considered a possible complication of infection even when recent imaging results are normal. A prompt CVT diagnosis is required to obtain a good outcome. Delayed diagnosis is mainly due to the rarity of the disease and physicians’ unawareness of this type of complication.

2014-01-01

406

33 CFR 154.1210 - Purpose and applicability.  

Code of Federal Regulations, 2013 CFR

...OIL OR HAZARDOUS MATERIAL IN BULK Response Plans for Animal Fats and Vegetable Oils Facilities § 154.1210 Purpose and applicability...operator of a facility that handles, stores, or transports animal fats or vegetable oils includingâ (1) A fixed MTR...

2013-07-01

407

Relative contributions of brain and cervical cord pathology to multiple sclerosis disability: a study with magnetisation transfer ratio histogram analysis  

Microsoft Academic Search

OBJECTIVETo assess (a) the correlations between magnetisation transfer ratio (MTR) histogram derived measures of the brain and the cervical cord from patients with different multiple sclerosis phenotypes and (b) the correlation between these metrics and clinical disability. Magnetisation transfer imaging is sensitive to the most destructive aspects of multiple sclerosis pathology. Magnetisation transfer ratio histogram analysis encompasses the macroscopic and

Marco Rovaris; Marco Bozzali; Giuseppe Santuccio; Giuseppe Iannucci; Maria Pia Sormani; Bruno Colombo; Giancarlo Comi; Massimo Filippi

2000-01-01

408

Catalog of experimental projects for a fissioning plasma reactor  

NASA Technical Reports Server (NTRS)

Experimental and theoretical investigations were carried out to determine the feasibility of using a small scale fissioning uranium plasma as the power source in a driver reactor. The driver system is a light water cooled and moderated reactor of the MTR type. The eight experiments and proposed configurations for the reactor are outlined.

Lanzo, C. D.

1973-01-01

409

Magnetization Transfer Imaging and Proton MR Spectroscopy in the Evaluation of Axonal Injury: Correlation with Clinical Outcome after Traumatic Brain Injury  

Microsoft Academic Search

BACKGROUND AND PURPOSE: Current imaging does not permit quantification of neural injury after traumatic brain injury (TBI) and therefore limits both the development of new treatments and the appropriate counseling of patients concerning prognosis. We evaluated the utility of magnetization transfer ratio (MTR) and proton MR spectroscopy in identifying pa- tients with neuronal injury after TBI. METHODS: Thirty patients with

Grant Sinson; Linda J. Bagley; Kim M. Cecil; Maria Torchia; Joseph C. McGowan; Robert E. Lenkinski; Tracy K. McIntosh; Robert I. Grossman

410

High bit rate mass data storage device  

NASA Technical Reports Server (NTRS)

The HDDR-II mass data storage system consists of a Leach MTR 7114 recorder reproducer, a wire wrapped, integrated circuit flat plane and necessary power supplies for the flat plane. These units, with interconnecting cables and control panel are enclosed in a common housing mounted on casters. The electronics used in the HDDR-II double density decoding and encoding techniques are described.

1973-01-01

411

Rectal cancer in Luxembourg : a national population-based data report, 1988–1998  

Microsoft Academic Search

BACKGROUND: Morphologic criteria which might help to support the need for a preventive strategy for early detection of rectal cancer were analysed. Population-based data on rectal adenomas with high-grade dysplastic changes (n = 199) and invasive adenocarcinomas (n = 912) registered by the national Morphologic Tumour Registry (MTR) and diagnosed in a central department of pathology in Luxembourg between 1988

René Scheiden; Julien Sand; Joseph Weber; Philippe Turk; Yolande Wagener; Catherine Capesius

2003-01-01

412

Mechanism and Consequences of Anaerobic Respiration of Cobalt by Shewanella oneidensis Strain MR-1 ?  

PubMed Central

Bacteria from the genus Shewanella are the most diverse respiratory organisms studied to date and can utilize a variety of metals and metal(loid)s as terminal electron acceptors. These bacteria can potentially be used in bioremediation applications since the redox state of metals often influences both solubility and toxicity. Understanding molecular mechanisms by which metal transformations occur and the consequences of by-products that may be toxic to the organism and thus inhibitory to the overall process is significant to future applications for bioremediation. Here, we examine the ability of Shewanella oneidensis to catalyze the reduction of chelated cobalt. We describe an unexpected ramification of [Co(III)-EDTA]? reduction by S. oneidensis: the formation of a toxic by-product. We found that [Co(II)-EDTA]2?, the product of [Co(III)-EDTA]? respiration, inhibited the growth of S. oneidensis strain MR-1 and that this toxicity was partially abolished by the addition of MgSO4. We demonstrate that [Co(III)-EDTA]? reduction by S. oneidensis requires the Mtr extracellular respiratory pathway and associated pathways required to develop functional Mtr enzymes (the c-type cytochrome maturation pathway) and ensure proper localization (type II secretion). The Mtr pathway is known to be required for a variety of substrates, including some chelated and insoluble metals and organic compounds. Understanding the full substrate range for the Mtr pathway is crucial for developing S. oneidensis strains as a tool for bioremediation.

Hau, Heidi H.; Gilbert, Alan; Coursolle, Dan; Gralnick, Jeffrey A.

2008-01-01

413

HOT CELL BUILDING, TRA632. FIRST FLOOR PLAN. PLOT PLAN SHOWS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. FIRST FLOOR PLAN. PLOT PLAN SHOWS RELATIONSHIP TO PLUG STORAGE BUILDING. ONE HOT CELL ENCLOSED IN CONCRETE SHIELDING. IDAHO OPERATIONS OFFICE MTR-632-IDO-1, 11/1952. INL INDEX NO. 531-0632-00-396-110560, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

414

HOT CELL BUILDING, TRA632. MEZZANINE PLAN. EQUIPMENT ROOM. WORK AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. MEZZANINE PLAN. EQUIPMENT ROOM. WORK AND STORAGE AREAS. ROOF SLABS. IDAHO OPERATIONS OFFICE MTR-632-IDO-3, 11/1952. INL INDEX NO. 531-0632-60-396-110562, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

415

HOT CELL BUILDING, TRA632. SECTION DETAILS OF SHIELD CONCRETE, OPERATING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. SECTION DETAILS OF SHIELD CONCRETE, OPERATING WINDOWS, CHARGING HOLES. IDAHO OPERATIONS OFFICE MTR-632-IDO-5, 11/1950. INL INDEX NO. 531-0632-60-396-110564, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

416

HOT CELL BUILDING, TRA632. INSTRUMENT FITTINGS, MASTER/SLAVE MANIPULATOR, "POT LID ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. INSTRUMENT FITTINGS, MASTER/SLAVE MANIPULATOR, "POT LID CRANE." IDAHO OPERATIONS OFFICE MTR-632-IDO-16, 11/1952. INL INDEX NO. 531-0632-40-396-110574, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

417

HOT CELL BUILDING, TRA632. ELEVATIONS FOR SOUTH, NORTH AND WEST ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. ELEVATIONS FOR SOUTH, NORTH AND WEST SIDES OF 1958 EXTENSION. H.K. FERGUSON CO. 895-MTR-ETR-632-A3, 12/1958. INL INDEX NO. 531-0632-00-279-101926, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

418

Manual therapies in myofascial trigger point treatment: a systematic review  

Microsoft Academic Search

Background and purpose: Myofascial pain syndrome (MPS) is thought by some authors the main cause of headache and neck pain. MPS is characterized by Myofascial Trigger Points (MTrPs). However, there are not many controlled studies that have analyzed the effects of the manual therapies in their treatment. The aim of this systematic review is to establish whether manual therapies have

César Fernández de las Peñas; Mónica Sohrbeck Campo; Josué Fernández Carnero; Juan Carlos Miangolarra Page

2005-01-01

419

Nondestructive Assay of Highly Enriched Spent Fuel.  

National Technical Information Service (NTIS)

Passive gamma-ray and neutron measurements have been made on irradiated MTR fuel at the Omega West Reactor. Detectors utilized include a Ge(Li) for gamma spectroscopy, a exp 235 U fission chamber for thermal neutrons, and a smaller exp 235 U fission chamb...

J. R. Phillips S. T. Hsue C. R. Hatcher K. Kaieda E. G. Medina

1978-01-01

420

Cognitive impairment as marker of diffuse brain abnormalities in early relapsing remitting multiple sclerosis  

PubMed Central

Objectives: To establish the frequency of cognitive impairment in a population based sample of patients with recently diagnosed relapsing-remitting multiple sclerosis (RRMS), and to determine the relation between cognitive abnormalities and the extent of macroscopic and microscopic tissue damage revealed by magnetic resonance imaging (MRI) and magnetisation transfer (MT) imaging. Methods: 58 patients with RRMS consecutively diagnosed in the previous six months in Aquitaine and 70 healthy controls underwent a battery of neuropsychological tests. Lesion load and atrophy indices (brain parenchymal fraction and ventricular fraction) were measured on brain MRI. MT ratio (MTR) histograms were obtained from lesions, normal appearing white matter (NAWM), and normal appearing grey matter (NAGM). Gadolinium enhanced lesions were counted. Results: 44 RRMS patients could be individually matched with healthy controls for age, sex, and education. Patients performed worse in tests of verbal and spatial memory, attention, information processing speed, inhibition, and conceptualisation. Measures of attention and information processing speed were correlated with lesion load, mean NAWM MTR, and the peak location of the NAGM MTR histogram in the patients. Multivariate regression analysis showed that lesion load and mean NAWM MTR were among the MR indices that were most significantly associated with impairment of attention and information processing speed in these early RRMS cases. Conclusions: Cognitive impairment appears to be common in the early stages of RRMS, mainly affecting attention, information processing speed, memory, inhibition, and conceptualisation. The severity of these deficits reflects the extent of the lesions and the severity of tissue disorganisation outside lesions.

Deloire, M; Salort, E; Bonnet, M; Arimone, Y; Boudineau, M; Amieva, H; Barroso, B; Ouallet, J; Pachai, C; Galliaud, E; Petry, K; Dousset, V; Fabrigoule, C; Brochet, B

2005-01-01

421

Single-Cell Imaging and Spectroscopic Analyses of Cr(VI) Reduction on the Surface of Bacterial Cells  

PubMed Central

We investigate single-cell reduction of toxic Cr(VI) by the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 (MR-1), an important bioremediation process, using Raman spectroscopy and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). Our experiments indicate that the toxic and highly soluble Cr(VI) can be efficiently reduced to the less toxic and non-soluble Cr2O3 nanoparticles by MR-1. Cr2O3 is observed to emerge as nanoparticles adsorbed on the cell surface and its chemical nature is identified by EDX imaging and Raman spectroscopy. Co-localization of Cr2O3 and cytochromes by EDX imaging and Raman spectroscopy suggests a terminal reductase role for MR-1 surface-exposed cytochromes MtrC and OmcA. Our experiments revealed that the cooperation of surface proteins OmcA and MtrC makes the reduction reaction most efficient, and the sequence of the reducing reactivity of the MR-1 is: wild type > single mutant ?mtrC or mutant ?omcA > double mutant (?omcA-?mtrC). Moreover, our results also suggest that the direct microbial Cr(VI) reduction and Fe(II) (hematite)-mediated Cr(VI) reduction mechanisms may co-exist in the reduction processes.

Wang, Yuanmin; Sevinc, Papatya C.; Balchik, Sara M.; Fridrickson, Jim; Shi, Liang; Lu, H. Peter

2013-01-01

422

5'-Alkyl-substituted analogs of 5'-methylthioadenosine as trypanocides.  

PubMed Central

5'-Deoxy-5'-(methylthio)adenosine (MTA) is a by-product of polyamine metabolism and is phosphoryolytically cleaved to adenine and 5-deoxy-5-(methylthio)ribose-1-phosphate (MTR-1-P) by MTA phosphorylase. In eukaryotes, adenine is subsequently salvaged and converted to nucleotides, while MTR-1-P is converted to methionine. We examined 5'-deoxy-5'-substituted analogs of MTA for trypanocidal activity in vitro and in vivo. 5'-Deoxy-5'-(hydroxyethyl)thioadenosine (HETA) and its 5'-bromo,5'-chloro and 5'-fluoro derivatives were cleaved by extracts of the African trypanosome Trypanosoma brucei brucei (Km for MTA, 11.5 microM; Km for HETA, 13.2 microM) in a phosphate-dependent reaction. HETA and the three halo analogs were 50% inhibitory to growth at 0.5 to 5.0 microM in vitro. Inhibition of growth was reversible by exogenous methionine and 2-keto-4-methylthiobutyric acid, an intermediate in methionine synthesis from MTR-1-P. HETA was selected for further study in vivo. When administered by miniosmotic pump (25 to 150 mg/kg/day for 7 days) to mice infected with T. brucei brucei, HETA effected 70 to 90% cure rates. Results of this study indicate that these analogs of MTA are converted to trypanocidal MTR-1-P analogs and that this approach deserves further consideration in the development of novel chemotherapy of trypanosomiasis.

Bacchi, C J; Sufrin, J R; Nathan, H C; Spiess, A J; Hannan, T; Garofalo, J; Alecia, K; Katz, L; Yarlett, N

1991-01-01

423

'Fishing' for Alternatives to Mountaintop Mining in Southern West Virginia  

EPA Science Inventory

Mountaintop removal mining (MTR) is a major industry in southern West Virginia with many detrimental effects for small to mid-sized streams, and interest in alternative, sustainable industries is on the rise. As a first step in a larger effort to assess the value of sport fisheri...

424

Secure Computer Systems: A Mathematical Model  

Microsoft Academic Search

This paper presents a set of rules of operation which guarantee that a computer systemcan remain secure while exhibiting certain desired external characteristics. The rules areeasily transformable into algorithms suitable for implementation on a digital computer.iiiPREFACEIn our introductory paper on secure computer systems (MTR-2547, Vol. I) we introduceda framework for mathematical modeling based upon general systems theory. We thendeveloped a

Len LaPadula

1996-01-01

425

PLUG STORAGE BUILDING, TRA611. STRUCTURAL DETAILS. FACE PLATE. FOURTEEN OPENINGS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PLUG STORAGE BUILDING, TRA-611. STRUCTURAL DETAILS. FACE PLATE. FOURTEEN OPENINGS LABELED FOR PLUGS FROM SPECIFIC SIZE GROUPS IN THE MTR. BLAW-KNOX 3150-811-2, 1/1951. INL INDEX NO. 531-0611-00-098-100694, REV. 1. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

426

Penetrability of the Outer Membrane of Neisseria gonorrhoeae in Relation to Acquired Resistance to Penicillin and Other Antibiotics  

PubMed Central

Acquired antibiotic resistance in Neisseria gonorrhoeae is principally associated with three genetic markers, penA, mtr, and penB. penA is a specific marker for penicillin resistance, whereas mtr and penB are nonspecific in conferring resistance to penicillin and several other antibiotics as well. It has been suggested that the nonspecific markers may cause a general decrease in the penetrability of the gonococcal outer membrane. To investigate this, antibiotic penetration of the outer membrane was studied in two isogenic strains—FA19 (susceptible parent) and FA140 (containing penA, mtr, and penB)—and also in a clinical isolate with multiple resistance. The method involved brief treatment of exponential cells with ethylenediaminetetraacetic acid at 5°C to disrupt the outer membrane barrier. The 50% inhibitory concentrations of antibiotics for treated and normal cells were measured turbidimetrically, and from their ratios outer membrane penetration barriers were calculated. Small barriers were observed for actinomycin D and benzylpenicillin, and these were very similar in the susceptible and resistant strains. Also, in FA140 no significant barriers for rifampin, erythromycin, and tetracycline were detected. These results suggest that mechanism(s) other than reduced outer membrane penetrability underlie acquired resistance due to penA, mtr, and penB. Images

Scudamore, R. Allan; Beveridge, Terrance J.; Goldner, Morris

1979-01-01

427

CONTROL HOUSE, TRA620. MASONS ERECT PUMICE BLOCK WALLS. BUILDING WILL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CONTROL HOUSE, TRA-620. MASONS ERECT PUMICE BLOCK WALLS. BUILDING WILL CONTROL ACCESS TO MTR AND OTHER "HOT" AND CLASSIFIED AREAS. INL NEGATIVE NO. 577. Unknown Photographer, 9/11/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

428

HOT CELL BUILDING, TRA632. ELEVATIONS. PUMICE BLOCK WALLS. BLOWER AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. ELEVATIONS. PUMICE BLOCK WALLS. BLOWER AND FILTER LOFT PLATFORM AND LADDER ON EAST SIDE. IDAHO OPERATIONS OFFICE MTR-632-IDO-4, 11/1952. INL INDEX NO. 531-0632-00-396-110563, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

429

ARMF, TRA660. NORTH, WEST AND EAST ELEVATIONS. PUMICE BLOCK WALLS. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ARMF, TRA-660. NORTH, WEST AND EAST ELEVATIONS. PUMICE BLOCK WALLS. VERTICAL LIFT DOOR IN WEST WALL. WINDOWS AND LOUVERS WERE LATER COVERED. H.K. FERGUSON 8956 MTR-ETR-660-53, 9/1959. INL INDEX NO. 531-0660-00-279-101994, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

430

COMPRESSOR BUILDING, TRA626. ELEVATIONS. WINDOWS. WALL SECTIONS. PUMICE BLOCK BUILDING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

COMPRESSOR BUILDING, TRA-626. ELEVATIONS. WINDOWS. WALL SECTIONS. PUMICE BLOCK BUILDING HOUSED COMPRESSORS FOR AIRCRAFT NUCLEAR PROPULSION EXPERIMENTS. MTR-626-IDO-2S, 3/1952. INL INDEX NO. 531-0626-00-396-110535, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

431

CHEMICAL PROCESSING TECHNOLOGY QUARTERLY PROGRESS REPORT, JANUARY-MARCH 1962  

Microsoft Academic Search

The processing of Al fuel, principally of the MTR-ETR type, is reported. ; Processing rate averaged 90% of flow sheet values for the entire operating ; period, and a U recovery of 99.85% was achieved. Aqueous Zr fuel processing ; studles continued with the objective of adapting the HF process to continuous ; dissolution-complexing in order to increase the capacity

J. R. ed

1962-01-01

432

33 CFR 154.1055 - Exercises.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Exercises. 154.1055 Section 154.1055...Plans for Oil Facilities § 154.1055 Exercises. (a) A response plan submitted...operator of an MTR facility must include an exercise program containing both announced...

2010-07-01

433

33 CFR 154.1055 - Exercises.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Exercises. 154.1055 Section 154.1055...Plans for Oil Facilities § 154.1055 Exercises. (a) A response plan submitted...operator of an MTR facility must include an exercise program containing both announced...

2009-07-01

434

33 CFR 154.1055 - Exercises.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Exercises. 154.1055 Section 154.1055...Plans for Oil Facilities § 154.1055 Exercises. (a) A response plan submitted...operator of an MTR facility must include an exercise program containing both announced...

2013-07-01

435

CHEMICAL PROCESSING TECHNOLOGY QUARTERLY PROGRESS REPORT, OCTOBER-DECEMBER 1961  

Microsoft Academic Search

The ICPP processed Al fuel, prtncipally of the MTR-ETR type, durtng this ; quarter. Newly designed and installed processing equipment exhibited excellent ; operating performance. This included direct-air-pulsed extraction, stripping and ; scrub columns, and a cascade-controlled continuous evaporator in first cycle ; product concentration service. Aqueous zirconium fuel processing studies ; continued with the objective of adapting the hydrofluoric

J. R. ed

1962-01-01

436

Diversion assumptions for high-powered research reactors. ISPO C-50 Phase 1.  

National Technical Information Service (NTIS)

This study deals with diversion assumptions for high-powered research reactors -- specifically, MTR fuel; pool- or tank-type research reactors with light-water moderator; and water, beryllium, or graphite reflectors, and which have a power level of 25 MW(...

F. T. Binford

1984-01-01

437

Evaluation of Research Reactors.  

National Technical Information Service (NTIS)

The present status of research reactors with highly enriched (93%) uranium fuel at JAERI, JRR-2 and JMTR is described. JRR-2 is a heterogeneous type of reactor, using heavy water as moderator and coolant. It uses both MTR type and cylindrical type of fuel...

1978-01-01

438

D919G polymorphism of methionine synthase gene is associated with blood pressure response to benazepril in Chinese hypertensive patients  

Microsoft Academic Search

Individual variation in drug response is considered to have multiple origins arising from interactions among susceptible genes and environmental factors. A total of 726 hypertensive patients who took benazepril 10 mg once a day for 15 days and their families from Huoqiu county of Anhui Province, China, were used to study the association between D919G polymorphism of methionine synthase (MTR) gene

Yan Zhang; Minmin Zhang; Tianhua Niu; Xin Xu; Guoying Zhu; Yong Huo; Changzhong Chen; Xiaobin Wang; Houxun Xing; Shaojie Peng; Aiqun Huang; Xiumei Hong; Xiping Xu

2004-01-01

439

GAMMA FACILITY, TRA641. PIPING LAYOUT FOR DEMINERALIZED WATER, DRAINS, SUMP. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

GAMMA FACILITY, TRA-641. PIPING LAYOUT FOR DEMINERALIZED WATER, DRAINS, SUMP. PICTORIAL VIEW OF CANAL AND LOCATION OF INPUTS AND DRAINS. IDAHO OPERATIONS OFFICE MTR-641-IDO-15P, 10/1954. INL INDEX NO. 531-0641-00-396-110615, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

440

HOT CELL BUILDING, TRA632. FIRST FLOOR FOUNDATION PLAN SHOWS SECTIONALIZED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. FIRST FLOOR FOUNDATION PLAN SHOWS SECTIONALIZED FLOOR LOADINGS AND CONCRETE SLAB THICKNESSES, A TYPICAL FEATURE OF NUCLEAR ARCHITECTURE. IDAHO OPERATIONS OFFICE MTR-632-IDO-2, 11/1952. INL INDEX NO. 531-0632-62-396-110561, REV. 1. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

441

Effect of Latent Myofascial Trigger Points on Strength Measurements of the Upper Trapezius: A Case-Controlled Trial  

PubMed Central

ABSTRACT Purpose: The purpose of this article was to determine whether strength is altered in the upper trapezius in the presence of latent myofascial trigger points (MTrP). Methods: This study was case controlled and used convenience sampling. The sample recruited was homogeneous with respect to age, sex, height, and body mass. Participants were assessed for the presence of latent MTrP in the upper trapezius and placed into two groups: an experimental group that had latent MTrP in the upper trapezius and a control group that did not. Eighteen women (mean age 21.4 y, SD 1.89; mean height 156.9 cm, SD 4.03; and mean body mass 51.7 kg, SD 5.84) made up the experimental group, and 19 women (mean age 20.3 y, SD 1.86; mean height 158.6 cm, SD 3.14; and mean body mass 53.2 kg, SD 5.17) made up the control group. We obtained strength measurements of the non-dominant arm using a handheld dynamometer and compared them between the two groups. Results: The difference in the strength measurements between the two groups was not statistically significant (p=0.59). Conclusions: The presence of latent MTrPs may not affect the strength of the upper trapezius.

Anshul

2011-01-01

442

Innovative Technology Summary Report: Membrane System for the Recovery of Volatile Organic Compounds from Remediation Off-Gases. Industry Programs and TRU and Mixed Waste Focus Area.  

National Technical Information Service (NTIS)

Membrane Technology and Research, Inc.'s (MTR's) membrane-based off-gas treatment technology separates the organic components from the off-gas stream, producing a VOC-free air stream that can be discharged or recycled to the gas-generating process. The me...

2001-01-01

443

Longevity, Stress Response, and Cancer in Aging Telomerase-Deficient Mice  

Microsoft Academic Search

Telomere maintenance is thought to play a role in signaling cellular senescence; however, a link with organismal aging processes has not been established. The telomerase null mouse provides an opportunity to understand the effects associated with critical telomere shortening at the organismal level. We studied a variety of physiological processes in an aging cohort of mTR?\\/? mice. Loss of telomere

Karl Lenhard Rudolph; Sandy Chang; Han-Woong Lee; Maria Blasco; Geoffrey J. Gottlieb; Carol Greider; Ronald A. DePinho

1999-01-01

444

Fabrication of U sub 3 O sub 8 -Al Dispersions.  

National Technical Information Service (NTIS)

The procedures used for the preparation by powder metallurgy of U sub 3 O sub 8 -Al dispersions, similar to those utilized in research nuclear reactors (MTR), are described in detail. Samples with U sub 3 O sub 8 content varying from 0 to 80 wt.% were pre...

A. M. de Figueredo P. I. Ferreira

1982-01-01

445

PROCESS WATER BUILDING, TRA605. EAST SIDE. CAMERA FACING WEST. REMOVABLE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PROCESS WATER BUILDING, TRA-605. EAST SIDE. CAMERA FACING WEST. REMOVABLE OPENINGS WERE NOT BENEFICIALLY USED FOR FUTURE EXPANSION. PART OF MTR APPEARS BEHIND BUILDING AT LEFT. ATR BUILDING IN BACKGROUND ON RIGHT. INL NEGATIVE NO. HD46-34-4. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

446

Forty Rural Schools: A Study of School Effectiveness.  

ERIC Educational Resources Information Center

A comparison of Middle Tennessee Rural (MTR) schools with the national sample of schools included in Kappa Delta Pi's Good Schools Project (GSP) focused on the areas of curriculum perspectives, goal attainment, classroom practices, interpersonal relations, commitment, discipline and safety, support services and facilities, and decision making. The…

Talbert, Elmer Gene; And Others

447

Structural and Functional Characteristics of Natural and Constructed Channels Draining a Reclaimed Mountaintop Removal and Valley Fill Coal Mine  

EPA Science Inventory

Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the USA. Among the changes are large-scale topographic recontouring, burial of headwater streams, and degradation of downstream water quality. The goals of our ...

448

Determination of the installation site and optimal capacity of the battery energy storage system for load leveling  

SciTech Connect

This study aims to show methods of determining the installation site and the optimal capacity of the battery energy storage system (BESS) to attain load leveling. The methods are based on the hardware characteristics of 20-kW/100-kWh and 1-MW/4-MWh prototype BESSs, which are already developed and are being developed, respectively. The candidate site of BESS installation is the secondary side of a distribution substation`s main transformer (MTr). These tacks are performed by first classifying the load pattern of an MTr and comparing it to the load pattern of a total power system. If the load factor improves, then the location is determined to be a BESS installation site. Subsequently, the optimal BESS capacity for an MTr is determined using the given operation pattern, the charging/discharging characteristics, and efficiency. Computational experimentation was performed on an actual distribution system in Korea. After determining the optimal capacity, they verified that installing the BESS on the selected MTr improved both daily and nightly load factors.

Jung, K.H. [POSCO Research Inst., Seoul (Korea, Republic of)] [POSCO Research Inst., Seoul (Korea, Republic of); Kim, H.; Rho, D. [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)] [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)

1996-03-01

449

Field Demonstration of a Membrane Process to Separate Nitrogen from Natural Gas  

SciTech Connect

The original proposal described the construction and operation of a 1 MMscfd treatment system to be operated at a Butcher Energy gas field in Ohio. The gas produced at this field contained 17% nitrogen. During pre-commissioning of the project, a series of well tests showed that the amount of gas in the field was significantly smaller than expected and that the nitrogen content of the wells was very high (25 to 30%). After evaluating the revised cost of the project, Butcher Energy decided that the plant would not be economical and withdrew from the project. Since that time, Membrane Technology and Research, Inc. (MTR) has signed a marketing and sales partnership with ABB Lummus Global, a large multinational corporation. MTR is now working with the company's Randall Gas Technology Group, a supplier of equipment and processing technology to the natural gas industry. Randall's engineering group first found a new site for the project at a North Texas Exploration (NTE) gas processing plant. The plant produced about 1 MMscfd of gas containing 24% nitrogen. The membrane unit was built to bring this gas to 4% nitrogen for delivery to the pipeline. The membrane skid was built by ABB. NTE ordered the required compressor and MTR made the membrane modules for a December 2004 delivery. However, the gas supply was not steady enough for field testing, and MTR/ABB have now located other sites for field testing and commercial development.

Kaaeid Lokhandwala

2005-12-15

450

Simulation of reactivity transients in current MTRs  

Microsoft Academic Search

This work aims at simulation of reactivity induced transients in High Enriched Uranium (HEU) and Low Enriched Uranium (LEU) cores of a typical Material Test research Reactor (MTR) using PARET code. The transient problem was forced through specification of externally inserted reactivity as a function of time. Reactivity insertions are idealized by ramps and steps. Superdelayed-critical transients, superprompt-critical transients and

Anwar M. Mirza; Salma Khanam; Nasir M. Mirza

1998-01-01

451

Brain damage as detected by magnetization transfer imaging is less pronounced in benign than in early relapsing multiple sclerosis  

Microsoft Academic Search

The trend to start disease-modifying therapy early in the course of multiple sclerosis makes it important to establish whether the benign form is a real entity. In previous studies, measures of magnetization transfer (MT) ratio (MTr) have been shown to provide good estimates of the amount of tissue damage occurring in multiple sclerosis brains. Thus, with the hypothesis that if

Nicola De Stefano; Marco Battaglini; M. L. Stromillo; Valentina Zipoli; M. L. Bartolozzi; Leonello Guidi; Gianfranco Siracusa; Emilio Portaccio; Antonio Giorgio; Sandro Sorbi; Antonio Federico; Maria Pia Amato

2006-01-01

452

Magnetization-Transfer Histogram Analysis of the Cervical Cord in Patients with Multiple Sclerosis  

Microsoft Academic Search

BACKGROUND AND PURPOSE: Previous studies have failed to show significant correla- tions between the number and extent of T2 spinal cord lesions and the clinical status of multiple sclerosis (MS) patients. We evaluated 1) whether it is feasible to create magnetization transfer- ratio (MTR) histograms of the cervical cord in patients with MS by using two different ac- quisition schemes,

Marco Bozzali; Maria A. Rocca; Giuseppe Iannucci; Clodoaldo Pereira; Giancarlo Comi; Massimo Filippi

1999-01-01

453

Field Demonstration of a Membrane Process to Separate Nitrogen from Natural Gas  

SciTech Connect

The original proposal described the construction and operation of a 1 MMscfd treatment system to be operated at a Butcher Energy gas field in Ohio. The gas produced at this field contained 17% nitrogen. During pre-commissioning of the project, a series of well tests showed that the amount of gas in the field was significantly smaller than expected and that the nitrogen content of the wells was very high (25 to 30%). After evaluating the revised cost of the project, Butcher Energy decided that the plant would not be economical and withdrew from the project. Since that time, Membrane Technology and Research, Inc. (MTR) has signed a marketing and sales partnership with ABB Lummus Global, a large multinational corporation. MTR will be working with the company's Randall Gas Technology Group, a supplier of equipment and processing technology to the natural gas industry. Randall's engineering group first found a new site for the project at a North Texas Exploration (NTE) gas processing plant. The plant produced about 1 MMscfd of gas containing 24% nitrogen. The membrane unit was built to bring this gas to 4% nitrogen for delivery to the pipeline. The membrane skid was built by ABB. NTE ordered the required compressor and MTR made the membrane modules for a December 2004 delivery. However, the gas supply was not steady enough for field testing, and MTR/ABB have now located other sites for field testing and commercial development.

Kaaeid Lokhandwala

2005-12-22

454

77 FR 12578 - Combined Notice of Filings #1  

Federal Register 2010, 2011, 2012, 2013

...ER12-1138-000. Applicants: Public Service Company of Colorado. Description: 2012-2-22--PSC-WAPA-Bijou SS BA Mtr 322 to be effective 1/27/2012. Filed Date: 2/22/12. Accession Number: 20120222-5071. Comments Due: 5...

2012-03-01

455

33 CFR 154.1029 - Worst case discharge.  

Code of Federal Regulations, 2013 CFR

...a) The response plan must use the appropriate criteria in this section to develop the worst case discharge. (b) For the MTR segment of a facility, not less thanâ (1) Where applicable, the loss of the entire capacity of all in-line...

2013-07-01

456

Enhanced reflectance X-ray absorption fine structure sensitivity using a whispering-gallery waveguide  

NASA Astrophysics Data System (ADS)

A new technique of reflectance X-ray absorption fine structure (REFL-XAFS) utilizing waveguides where X-rays are reflected many times along the waveguide surface is discussed. The multiple total reflection (MTR) phenomenon highly increases X-ray interaction with the waveguide surface and hence offers higher sensitivity compared to conventional (single reflection) REFL-XAFS. On the one hand, this technique is a direct structural method for characterizing waveguides (e.g. capillaries) where the application of other methods is very difficult. On the other hand, the conventional thin wafer can be transformed to a whispering-gallery (WG) waveguide by bending to a curved mirror. Ray tracing calculations demonstrate that the WG waveguide is very suitable for REFL-XAFS measurements. This method was experimentally realized for a cylindrically bent silica wafer with the surface covered with a GeO 2 monolayer. The Ge K-edge REFL-XAFS measurements were performed using both MTR and conventional techniques. The MTR technique allows us to achieve about 20-fold gain in the signal-to-background ratio compared with the conventional technique. The MTR phenomenon discussed in this paper can provide new possibilities to study clean surfaces, ultrathin films and adsorbed molecules.

Chernov, V. A.; Kim, S. K.; Kovalenko, N. V.; Zolotarev, K. V.

2000-06-01

457

33 CFR 154.100 - Applicability.  

Code of Federal Regulations, 2013 CFR

...the facility if its storage tanks and piping are gas free. (c) Upon a determination by the COTP under § 154.1016 that an MTR facility, as defined in subpart F, could reasonably be expected to cause substantial harm to the environment by...