Physicians' use of plasma methylmalonic acid as a diagnostic tool

DEFF Research Database (Denmark)

Hvas, A M; Vestergaard, H; Gerdes, Lars Ulrik

2000-01-01

with a plasma methylmalonic acid measurement above the reference interval. Information on diagnostic decisions was available for 177 patients. MAIN OUTCOME MEASURES: Reasons for requesting plasma methylmalonic acid and the reactions to the finding of elevated plasma methylmalonic acid. RESULTS: An explicit......OBJECTIVES: To investigate physicians' reasons for requesting plasma methylmalonic acid and their reactions to an increased concentration of plasma methylmalonic acid. DESIGN: Study of medical records. SETTING: Three somatic district hospitals in Denmark. SUBJECTS: Medical records of 198 patients...... reason for requesting plasma methylmalonic acid was stated in 57% of 198 examined medical records, known or suspected anaemia being the most frequent reason. No further action was taken in 109 (62%) of the 177 cases available for follow-up. Amongst the remaining 68 patients, the finding of an increased...

SERUM METHYLMALONIC ACID DAN HOMOCYSTEIN DALAM MENDIAGNOSIS ANEMIA MEGALOBLASTIK AKIBAT DEFISIENSI KOBALAMIN DAN FOLAT PADA TRAVEL MEDICINE

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Made Gian Indra Rahayuda

2014-09-01

Full Text Available Anemia adalah salah satu masalah kesehatan global yang utama, terutama pada negara-negara berkembang.Anemia adalah kondisi dimana massa sel darah merah dan/atau massa hemoglobin yang beredar dalam tubuh menurun hingga dibawah kadar normal sehingga tidak dapat berfungsi dengan baik dalam menyediakan oksigen untuk jaringan tubuh. Salah satu jenis yang banyak ditemukan adalah anemia megaloblastik.Anemia megaloblastik paling banyak disebabkan oleh kekurangan vitamin B12(kobalamin dan folat.Salah satu penyebab anemia defisiensi kobalamin dan folat adalah tropical sprue.Anemia defisiensi kobalamin dan asam folat memberikan gambaran yang serupa namun pada defisiensi kobalamin terdapat gejala neuropati.Batas normal serum folat antara 3-15 ng/mL.Folat eritrosit batas normalnya dari 150 – 600 ng/mL.Pada defisiensi kobalamin, serum kobalamin menurun di bawah cut off point100pg/mL (normalnya 100- 400pg/mL.Pemeriksaan lain seperti homocystein, methylmalonic acid, atau formioglutamic acid(FIGLU yang meningkat pada urin dapat memastikan diagnosis defisiensi kobalamindan asam folat. Belum ada konsensus mengenai cut off point Homocystein dan MMA. Homocysteine telah dianggap meningkat bila kadarnya di atas 12-14 µmol/L pada wanita dan di atas 14-15 µmol/L. Menurut penelitian yang dilakukan Robert et al pada kasus defisiensi kobalamin, kadar serum tHcy> 15.0 µmol/L.Kebanyakan penelitian menganggap peningkatan MMA pada defisiensi kobalamin adalah >0.28 µmol/L, tapi cut off point yang beredar bervariasi antara 0.21-0.48 µmol/L.Kadar MMA meningkat dalam serumdan urin pada defisiensi kobalamin, sedangkan pada defisiensi folat MMA normal.

The marker of cobalamin deficiency, plasma methylmalonic acid, correlates to plasma creatinine

DEFF Research Database (Denmark)

Hvas, A M; Juul, S; Gerdes, Lars Ulrik

2000-01-01

OBJECTIVE: To examine the relationship between the two diagnostic tests, plasma methylmalonic acid and plasma cobalamins, and their association with plasma creatinine, age and sex. DESIGN: Cross-sectional study of simultaneous laboratory measurements. SETTING: County of Aarhus, Denmark. SUBJECTS......: Records on 1689 patients who had their first plasma methylmalonic acid measurement during 1995 and 1996, and who had a simultaneous measurement of plasma cobalamins. Plasma creatinine values measured within a week of measurements of plasma methylmalonic acid and plasma cobalamins were available for 1255...... of the patients. MAIN OUTCOME MEASURES: Predictors of variation in plasma methylmalonic acid; plasma cobalamins, plasma creatinine, age and sex. RESULTS: Plasma methylmalonic acid was positively correlated with plasma creatinine, even for plasma creatinine within the normal range. These associations remained...

Adenoviral-mediated correction of methylmalonyl-CoA mutase deficiency in murine fibroblasts and human hepatocytes

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Korson Mark

2007-04-01

Full Text Available Abstract Background Methylmalonic acidemia (MMA, a common organic aciduria, is caused by deficiency of the mitochondrial localized, 5'deoxyadenosylcobalamin dependent enzyme, methylmalonyl-CoA mutase (MUT. Liver transplantation in the absence of gross hepatic dysfunction provides supportive therapy and metabolic stability in severely affected patients, which invites the concept of using cell and gene delivery as future treatments for this condition. Methods To assess the effectiveness of gene delivery to restore the defective metabolism in this disorder, adenoviral correction experiments were performed using murine Mut embryonic fibroblasts and primary human methylmalonyl-CoA mutase deficient hepatocytes derived from a patient who harbored two early truncating mutations, E224X and R228X, in the MUT gene. Enzymatic and expression studies were used to assess the extent of functional correction. Results Primary hepatocytes, isolated from the native liver after removal subsequent to a combined liver-kidney transplantation procedure, or Mut murine fibroblasts were infected with a second generation recombinant adenoviral vector that expressed the murine methylmalonyl-CoA mutase as well as eGFP from distinct promoters. After transduction, [1-14C] propionate macromolecular incorporation studies and Western analysis demonstrated complete correction of the enzymatic defect in both cell types. Viral reconstitution of enzymatic expression in the human methylmalonyl-CoA mutase deficient hepatocytes exceeded that seen in fibroblasts or control hepatocytes. Conclusion These experiments provide proof of principle for viral correction in methylmalonic acidemia and suggest that hepatocyte-directed gene delivery will be an effective therapeutic treatment strategy in both murine models and in human patients. Primary hepatocytes from a liver that was unsuitable for transplantation provided an important resource for these studies.

Population Reference Values for Serum Methylmalonic Acid Concentrations and Its Relationship with Age, Sex, Race-Ethnicity, Supplement Use, Kidney Function and Serum Vitamin B12 in the Post-Folic Acid Fortification Period

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Vijay Ganji

2018-01-01

Full Text Available Serum methylmalonic acid (MMA is elevated in vitamin B-12 deficiency and in kidney dysfunction. Population reference values for serum MMA concentrations in post-folic acid fortification period are lacking. Aims of this study were to report the population reference values for serum MMA and to evaluate the relation between serum MMA and sex, age, race-ethnicity, kidney dysfunction and vitamin B-12. We used data from three National Health and Nutrition Examination Surveys, 1999–2000, 2001–2002 and 2003–2004 conducted after folic acid fortification commenced (n = 18,569. Geometric mean MMA was ≈22.3% higher in non-Hispanic white compared to non-Hispanic black (141.2 vs. 115.5 nmol/L and was ≈62.7% higher in >70 years old persons compared to 21–30 years old persons (196.9 vs. 121.0 nmol/L. Median serum MMA was ≈28.5% higher in the 1st the quartile of serum vitamin B-12 than in the 4th quartile of serum vitamin B-12 and was ≈35.8% higher in the 4th quartile of serum creatinine than in the 1st quartile of serum creatinine. Multivariate-adjusted serum MMA concentration was significantly associated with race-ethnicity (p < 0.001 and age (p < 0.001 but not with sex (p = 0.057. In this large US population based study, serum MMA concentrations presented here reflect the post-folic acid fortification scenario. Serum MMA concentrations begin to rise at the age of 18–20 years and continue to rise afterwards. Age-related increase in serum MMA concentration is likely to be due to a concomitant decline in kidney function and vitamin B-12 status.

Nutritional Supplementation with Chlorella pyrenoidosa Lowers Serum Methylmalonic Acid in Vegans and Vegetarians with a Suspected Vitamin B₁₂ Deficiency.

Science.gov (United States)

Merchant, Randall Edward; Phillips, Todd W; Udani, Jay

2015-12-01

Since vitamin B12 occurs in substantial amounts only in foods derived from animals, vegetarians and particularly vegans are at risk of developing deficiencies of this essential vitamin. The chlorella used for this study is a commercially available whole-food supplement, which is believed to contain the physiologically active form of the vitamin. This exploratory open-label study was performed to determine if adding 9 g of Chlorella pyrenoidosa daily could help mitigate a vitamin B12 deficiency in vegetarians and vegans. Seventeen vegan or vegetarian adults (26-57 years of age) with a known vitamin B12 deficiency, as evidenced by a baseline serum methylmalonic acid (MMA) level above 270 nmol/L at screening, but who otherwise appeared healthy were enrolled in the study. Each participant added 9 g of C. pyrenoidosa to their daily diet for 60 ± 5 days and their serum MMA, vitamin B12, homocysteine (Hcy) levels as well as mean corpuscular volume (MCV), hemoglobin (Hgb), and hematocrit (Hct) were measured at 30 and 60 days from baseline. After 30 and 60 days, the serum MMA level fell significantly (P < .05) by an average ∼34%. Fifteen of the 17 (88%) subjects showed at least a 10% drop in MMA. At the same time, Hcy trended downward and serum vitamin B12 trended upward, while MCV, Hgb, and Hct appeared unchanged. The results of this work suggest that the vitamin B12 in chlorella is bioavailable and such dietary supplementation is a natural way for vegetarians and vegans to get the vitamin B12 they need.

Genetics Home Reference: methylmalonic acidemia

Science.gov (United States)

... Ardinger HH, Wallace SE, Amemiya A, Bean LJH, Bird TD, Ledbetter N, Mefford HC, Smith RJH, Stephens ... patients with the cblD inborn error of cobalamin metabolism. J Pediatr. 2009 Apr;154(4):551-6. ...

Acute Pancreatitis with Rapid Clinical Improvement in a Child with Isovaleric Acidemia

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Elpis Mantadakis

2013-01-01

Full Text Available Isovaleric acidemia is a rare branched-chain organic acidemia. The authors describe a 3.5-year-old girl with isovaleric acidemia and acute abdominal pain associated with bilious emesis. Elevated serum amylase and abdominal ultrasonography demonstrating an enlarged and edematous pancreas, along with the presence of peripancreatic exudates, confirmed the presence of acute pancreatitis. The patient recovered quickly with intravenous hydration, pancreatic rest, and administration of intravenous L-carnitine. Pancreatitis should be ruled out in the context of vomiting in any patient with isovaleric acidemia. Conversely, branched-chain organic acidemias should be included in the differential diagnosis of any child with pancreatitis of unknown origin.

Fetal progenitor cell transplantation treats methylmalonic aciduria in a mouse model

International Nuclear Information System (INIS)

Buck, Nicole E.; Pennell, Samuel D.; Wood, Leonie R.; Pitt, James J.; Allen, Katrina J.; Peters, Heidi L.

2012-01-01

Highlights: ► Fetal cells were transplanted into a methylmalonic acid mouse model. ► Cell engraftment was detected in liver, spleen and bone marrow. ► Biochemical disease correction was measured in blood samples. ► A double dose of 5 million cells (1 week apart) proved more effective. ► Higher levels of engraftment may be required for greater disease correction. -- Abstract: Methylmalonic aciduria is a rare disorder caused by an inborn error of organic acid metabolism. Current treatment options are limited and generally focus on disease management. We aimed to investigate the use of fetal progenitor cells to treat this disorder using a mouse model with an intermediate form of methylmalonic aciduria. Fetal liver cells were isolated from healthy fetuses at embryonic day 15–17 and intravenously transplanted into sub-lethally irradiated mice. Liver donor cell engraftment was determined by PCR. Disease correction was monitored by urine and blood methylmalonic acid concentration and weight change. Initial studies indicated that pre-transplantation sub-lethal irradiation followed by transplantation with 5 million cells were suitable. We found that a double dose of 5 million cells (1 week apart) provided a more effective treatment. Donor cell liver engraftment of up to 5% was measured. Disease correction, as defined by a decrease in blood methylmalonic acid concentration, was effected in methylmalonic acid mice transplanted with a double dose of cells and who showed donor cell liver engraftment. Mean plasma methylmalonic acid concentration decreased from 810 ± 156 (sham transplanted) to 338 ± 157 μmol/L (double dose of 5 million cells) while mean blood C3 carnitine concentration decreased from 20.5 ± 4 (sham transplanted) to 5.3 ± 1.9 μmol/L (double dose of 5 million cells). In conclusion, higher levels of engraftment may be required for greater disease correction; however these studies show promising results for cell transplantation biochemical

Fetal progenitor cell transplantation treats methylmalonic aciduria in a mouse model

Energy Technology Data Exchange (ETDEWEB)

Buck, Nicole E., E-mail: nicole.buck@mcri.edu.au [Metabolic Research, Murdoch Childrens Research Institute, The University of Melbourne, Department of Paediatrics, Royal Children' s Hospital, Flemington Road, Parkville, VIC 3052 (Australia); Pennell, Samuel D.; Wood, Leonie R. [Metabolic Research, Murdoch Childrens Research Institute, The University of Melbourne, Department of Paediatrics, Royal Children' s Hospital, Flemington Road, Parkville, VIC 3052 (Australia); Pitt, James J. [Victorian Clinical Genetics Services, Murdoch Childrens Research Institute, Royal Children' s Hospital, Parkville (Australia); Allen, Katrina J. [Gastro and Food Allergy, Murdoch Childrens Research Institute, Parkville (Australia); Peters, Heidi L. [Metabolic Research, Murdoch Childrens Research Institute, The University of Melbourne, Department of Paediatrics, Royal Children' s Hospital, Flemington Road, Parkville, VIC 3052 (Australia)

2012-10-12

Highlights: Black-Right-Pointing-Pointer Fetal cells were transplanted into a methylmalonic acid mouse model. Black-Right-Pointing-Pointer Cell engraftment was detected in liver, spleen and bone marrow. Black-Right-Pointing-Pointer Biochemical disease correction was measured in blood samples. Black-Right-Pointing-Pointer A double dose of 5 million cells (1 week apart) proved more effective. Black-Right-Pointing-Pointer Higher levels of engraftment may be required for greater disease correction. -- Abstract: Methylmalonic aciduria is a rare disorder caused by an inborn error of organic acid metabolism. Current treatment options are limited and generally focus on disease management. We aimed to investigate the use of fetal progenitor cells to treat this disorder using a mouse model with an intermediate form of methylmalonic aciduria. Fetal liver cells were isolated from healthy fetuses at embryonic day 15-17 and intravenously transplanted into sub-lethally irradiated mice. Liver donor cell engraftment was determined by PCR. Disease correction was monitored by urine and blood methylmalonic acid concentration and weight change. Initial studies indicated that pre-transplantation sub-lethal irradiation followed by transplantation with 5 million cells were suitable. We found that a double dose of 5 million cells (1 week apart) provided a more effective treatment. Donor cell liver engraftment of up to 5% was measured. Disease correction, as defined by a decrease in blood methylmalonic acid concentration, was effected in methylmalonic acid mice transplanted with a double dose of cells and who showed donor cell liver engraftment. Mean plasma methylmalonic acid concentration decreased from 810 {+-} 156 (sham transplanted) to 338 {+-} 157 {mu}mol/L (double dose of 5 million cells) while mean blood C3 carnitine concentration decreased from 20.5 {+-} 4 (sham transplanted) to 5.3 {+-} 1.9 {mu}mol/L (double dose of 5 million cells). In conclusion, higher levels of engraftment may

Acute Pancreatitis with Rapid Clinical Improvement in a Child with Isovaleric Acidemia

OpenAIRE

Mantadakis, Elpis; Chrysafis, Ioannis; Tsouvala, Emmanouela; Evangeliou, Athanassios; Chatzimichael, Athanassios

2013-01-01

Isovaleric acidemia is a rare branched-chain organic acidemia. The authors describe a 3.5-year-old girl with isovaleric acidemia and acute abdominal pain associated with bilious emesis. Elevated serum amylase and abdominal ultrasonography demonstrating an enlarged and edematous pancreas, along with the presence of peripancreatic exudates, confirmed the presence of acute pancreatitis. The patient recovered quickly with intravenous hydration, pancreatic rest, and administration of intravenous L...

Fuzzy modeling for Vitamin B12 deficiency

NARCIS (Netherlands)

Wilbik, A.M.; van Loon, S.L.M.; Boer, A.K.; Kaymak, U.; Scharnhorst, V.; Carvalho, J.; Lesot, M.J.; Kaymak, U.; Vieira, S.; Bouchon-Meunier, B.; Yager, R.

2016-01-01

Blood vitamin B12 levels are not representative for actual vitamin B12 status in tissue. Instead plasma methylmalonic acid (MMA) levels can be measured because MMA concentrations increase relatively early in the course of vitamin B12 deficiency. However, MMA levels in plasma may also be increased

Genetics Home Reference: combined malonic and methylmalonic aciduria

Science.gov (United States)

... links) Health Topic: Genetic Brain Disorders Health Topic: Lipid Metabolism Disorders Genetic and Rare Diseases Information Center (1 link) Combined malonic and methylmalonic aciduria Additional NIH Resources (1 link) National Human Genome Research Institute: NHGRI Researchers Serve Up Mysterious ...

Genetics Home Reference: glutaric acidemia type I

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... Glutaric acidemia type 1 in patients of Lumbee heritage from North Carolina. Mol Genet Metab. 2006 May; ... 825-8. Review. Citation on PubMed More from Genetics Home Reference Bulletins Genetics Home Reference Celebrates Its ...

Autism in patients with propionic acidemia

NARCIS (Netherlands)

Witters, P.; Debbold, E.; Crivelly, K.; Kerckhove, K. Vande; Corthouts, K.; Debbold, B.; Andersson, H.; Vannieuwenborg, L.; Geuens, S.; Baumgartner, M.; Kozicz, L.T.; Settles, L.; Morava, E.

2016-01-01

Certain inborn errors of metabolism have been suggested to increase the risk of autistic behavior. In an animal model, propionic acid ingestion triggered abnormal behavior resembling autism. So far only a few cases were reported with propionic acidemia and autistic features. From a series of twelve

Simultaneous analysis of amino acid and organic acid by NMR spectrometry, 2. Diagnostic aids for inborn error of metabolism

Energy Technology Data Exchange (ETDEWEB)

Koda, Naoya; Yamaguchi, Shuichi; Mori, Takeshi.

1987-09-01

Analysis of urine from patients with inborn error of metabolism were studied by /sup 1/H-nuclear magnetic resonance (NMR) spectrometry. Diseases studied were as follows; phenylketonuria, biotin responsive multiple carboxylase deficiency, non-ketotic hyperglycinemia, 3-ketothiolase deficiency, alkaptonuria, methylmalonic acidemia, isovaleric acidemia, glutaric aciduria, argininosuccinic aciduria and hyperornithinemia. In each disease, specific metabolites in urine were recognized by NMR spectrometry. This method is accomplished within 10 minutes with non-treated small volume of urine and will be successfully available for the screening andor diagnosis of inherited metabolic diseases of amino acid and organic acid.

Plasma total odd-chain fatty acids in the monitoring of disorders of propionate, methylmalonate and biotin metabolism

NARCIS (Netherlands)

Coker, M.; de Klerk, J. B.; Poll-The, B. T.; Huijmans, J. G.; Duran, M.

1996-01-01

Total plasma odd-numbered long-chain fatty acids were analysed in patients with methylmalonic acidaemia (vitamin B12-responsive and unresponsive), combined methylmalonic acidaemia/homocystinuria (CblC), propionic acidaemia (both neonatal-onset and late-onset), biotinidase deficiency and

Genetics Home Reference: methylmalonic acidemia with homocystinuria

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... or Free article on PubMed Central Kräutler B. Biochemistry of B12-cofactors in human metabolism. Subcell Biochem. ... not be used as a substitute for professional medical care or advice. Users with questions about a ...

Selective screening in neonates suspected to have inborn errors of ...

African Journals Online (AJOL)

Results: 13 patients (32.5%) were diagnosed as having IEM, 7 of them (53.8%) had urea cycle defect, 2 (15.4%) had maple syrup urine disease, while methylmalonic acidemia, fatty acid oxidation defect, mitochondrial disease, and galactosemia were diagnosed in one patient each (7.7%). Out of these patients, 12 patients ...

Simultaneous analysis of amino acid and organic acid by NMR spectrometry, 2

International Nuclear Information System (INIS)

Koda, Naoya; Yamaguchi, Shuichi; Mori, Takeshi.

1987-01-01

Analysis of urine from patients with inborn error of metabolism were studied by 1 H-nuclear magnetic resonance (NMR) spectrometry. Diseases studied were as follows; phenylketonuria, biotin responsive multiple carboxylase deficiency, non-ketotic hyperglycinemia, 3-ketothiolase deficiency, alkaptonuria, methylmalonic acidemia, isovaleric acidemia, glutaric aciduria, argininosuccinic aciduria and hyperornithinemia. In each disease, specific metabolites in urine were recognized by NMR spectrometry. This method is accomplished within 10 minutes with non-treated small volume of urine and will be successfully available for the screening and/or diagnosis of inherited metabolic diseases of amino acid and organic acid. (author)

Long-term continuous N-carbamylglutamate treatment in frequently decompensated propionic acidemia: a case report.

Science.gov (United States)

Tummolo, Albina; Melpignano, Livio; Carella, Antonella; Di Mauro, Anna Maria; Piccinno, Elvira; Vendemiale, Marcella; Ortolani, Federica; Fedele, Stefania; Masciopinto, Maristella; Papadia, Francesco

2018-04-22

Propionic acidemia is a rare autosomal recessive inherited metabolic disorder that can inhibit the synthesis of N-acetylglutamate, the obligatory activator in urea synthesis, leading to hyperammonemia. N-carbamylglutamate ameliorates hyperammonemia in decompensated propionic acidemia. The effects of long-term continuous N-acetylglutamate administration in such patients are unknown. We report our clinical experience with continuous administration of N-acetylglutamate for 6 years in a patient with propionic acidemia frequently presenting with hyperammonemia. A male Caucasian patient with frequently decompensated propionic acidemia and hyperammonemia was admitted 78 times for acute attacks during the first 9 years of his life. Continuous daily treatment with oral N-carbamylglutamate 100 mg/kg (50 mg/kg after 6 months) was initiated. During 6 years of treatment, he had a significant decrease in his mean plasma ammonia levels (75.7 μmol/L vs. 140.3 μmol/L before N-carbamylglutamate therapy, p N-acetylglutamate administration outside the emergency setting. If this observation is confirmed, future studies should aim to optimize the dosage and explore effects of the dosage requirements on other drugs and on protein tolerance.

METHYLMALONIC ACID AND HOMOCYSTEIN SERUM IN DIAGNOSING MEGALOBLASTIC ANEMIA DUE TO COBALAMIN AND FOLATE DEFICIENCY IN TRAVEL MEDICINE

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Made Gian Indra Rahayuda

2014-01-01

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Anemia is a major global health problem, especially in developing countries. Anemia is a condition where the red blood cell mass and / or hemoglobin mass that circulating in the body was decreased to below normal level so it can not function well in providing oxygen to the body tissues. One of the most common type is megaloblastic anemia. Megaloblastic anemia is mostly caused by vitamin B12 (cobalamin and folate deficiency. One of the causes of cobalamin and folate deficiency anemia is tropical sprue. Cobalamin deficiency anemia and folate deficiency anemia gives a similar symptom, but in cobalamin deficiency there is neuropathy symptoms. Normal serum folate is between 3-15 ng/mL. Normal folate erythrocyte is 150-600 ng/mL. In cobalamin deficiency, serum cobalamin decreased below the cut off point 100pg/mL (normally 100 - 400pg/mL. Other examination such as elevated homocysteine??, methylmalonic acid, or formioglutamic acid (FIGLU in the urine can confirm the diagnosis of cobalamin and folic acid deficiency. There is no consensus on the cut-off point of homocysteine ??and MMA. Homocysteine ??has been considered to increase when the levels are above 12-14 ?mol /L in women and in the 14-15 ?mol/L. According to research by Robert et al in the case of cobalamin deficiency, serum tHcy> 15.0 ?mol/L. Most research considers the increase of MMA in cobalamin deficiency is> 0:28 ?mol / L, but the cut off point in circulation varies between 0:21 to 0:48 ?mol/L. MMA level is increased in serum and urine in cobalamin deficiency, whereas MMA normal in folate deficiency. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font

Combined indicator of vitamin B 12 status: modification for missing biomarkers and folate status and recommendations for revised cut-points

Science.gov (United States)

Background: A novel approach to determine vitamin B 12 status is to combine four blood markers: total B 12 (B 12 ), holotranscobalamin (holoTC), methylmalonic acid (MMA) and total homocysteine (tHcy). This combined indicator of B 12 status is expressed as cB 12 = log 10 [(holoTC · B 12 )/ (MMA · Hcy...

Severe metabolic or mixed acidemia on intensive care unit admission: incidence, prognosis and administration of buffer therapy. A prospective, multiple-center study.

Science.gov (United States)

Jung, Boris; Rimmele, Thomas; Le Goff, Charlotte; Chanques, Gérald; Corne, Philippe; Jonquet, Olivier; Muller, Laurent; Lefrant, Jean-Yves; Guervilly, Christophe; Papazian, Laurent; Allaouchiche, Bernard; Jaber, Samir

2011-01-01

In this study, we sought describe the incidence and outcomes of severe metabolic or mixed acidemia in critically ill patients as well as the use of sodium bicarbonate therapy to treat these illnesses. We conducted a prospective, observational, multiple-center study. Consecutive patients who presented with severe acidemia, defined herein as plasma pH below 7.20, were screened. The incidence, sodium bicarbonate prescription and outcomes of either metabolic or mixed severe acidemia were analyzed. Among 2, 550 critically ill patients, 200 (8%) presented with severe acidemia, and 155 (6% of the total admissions) met the inclusion criteria. Almost all patients needed mechanical ventilation and vasopressors during their ICU stay, and 20% of them required renal replacement therapy within the first 24 hours of their ICU stay. Severe metabolic or mixed acidemia was associated with a mortality rate of 57% in the ICU. Delay of acidemia recovery as opposed to initial pH value was associated with increased mortality in the ICU. The type of acidemia did not influence the decision to administer sodium bicarbonate. The incidence of severe metabolic or mixed acidemia in critically ill patients was 6% in the present study, and it was associated with a 57% mortality rate in the ICU. In contradistinction with the initial acid-base parameters, the rapidity of acidemia recovery was an independent risk factor for mortality. Sodium bicarbonate prescription was very heterogeneous between ICUs. Further studies assessing specific treatments may be of interest in this population.

Severe metabolic or mixed acidemia on intensive care unit admission: incidence, prognosis and administration of buffer therapy. a prospective, multiple-center study

Science.gov (United States)

2011-01-01

Introduction In this study, we sought describe the incidence and outcomes of severe metabolic or mixed acidemia in critically ill patients as well as the use of sodium bicarbonate therapy to treat these illnesses. Methods We conducted a prospective, observational, multiple-center study. Consecutive patients who presented with severe acidemia, defined herein as plasma pH below 7.20, were screened. The incidence, sodium bicarbonate prescription and outcomes of either metabolic or mixed severe acidemia were analyzed. Results Among 2, 550 critically ill patients, 200 (8%) presented with severe acidemia, and 155 (6% of the total admissions) met the inclusion criteria. Almost all patients needed mechanical ventilation and vasopressors during their ICU stay, and 20% of them required renal replacement therapy within the first 24 hours of their ICU stay. Severe metabolic or mixed acidemia was associated with a mortality rate of 57% in the ICU. Delay of acidemia recovery as opposed to initial pH value was associated with increased mortality in the ICU. The type of acidemia did not influence the decision to administer sodium bicarbonate. Conclusions The incidence of severe metabolic or mixed acidemia in critically ill patients was 6% in the present study, and it was associated with a 57% mortality rate in the ICU. In contradistinction with the initial acid-base parameters, the rapidity of acidemia recovery was an independent risk factor for mortality. Sodium bicarbonate prescription was very heterogeneous between ICUs. Further studies assessing specific treatments may be of interest in this population. PMID:21995879

Expanded Newborn Screening for Inborn Errors of Metabolism and Genetic Characteristics in a Chinese Population

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Kejian Guo

2018-04-01

Full Text Available The incidence of inborn errors of metabolisms (IEMs varies dramatically in different countries and regions. Expanded newborn screening for IEMs by tandem mass spectrometry (MS/MS is an efficient approach for early diagnosis and presymptomatic treatment to prevent severe permanent sequelae and death. To determine the characteristics of IEMs and IEMs-associated mutations in newborns in Jining area, China, 48,297 healthy neonates were recruited for expanded newborn screening by MS/MS. The incidence of IEMs was 1/1178 in Jining, while methylmalonic acidemia, phenylketonuria, and primary carnitine deficiency ranked the top 3 of all detected IEMs. Thirty mutations in nine IEMs-associated genes were identified in 28 confirmed cases. As 19 cases with the mutations in phenylalanine hydroxylase (PAH, solute carrier family 22 member 5 (SLC22A5, and methylmalonic aciduria (cobalamin deficiency cblC type with homocystinuria (MMACHC genes, respectively, it suggested that mutations in the PAH, SLC22A5, and MMACHC genes are the predominant causes of IEMs, leading to the high incidence of phenylketonuria, primary carnitine deficiency, and methylmalonic acidemia, respectively. Our work indicated that the overall incidence of IEMs is high and the mutations in PAH, SLC22A5, and MMACHC genes are the leading causes of IEMs in Jining area. Therefore, it is critical to increase the coverage of expanded newborn screening by MS/MS and prenatal genetic consulting in Jining area.

Isovaleric acidemia: an integrated approach toward predictive laboratory medicine

NARCIS (Netherlands)

Dercksen, M.

2014-01-01

Isovaleric acidemia (IVA) is an autosomal recessive disorder caused by isovaleryl-CoA dehydrogenase (IVD) deficiency (E.C.1.2.99.10) and patients present with a heterogeneous phenotype, ranging from metabolically mild and/or intermittent to metabolically severe. A cohort of ten IVA patients with a

Molecular recognition at methyl methacrylate/n-butyl acrylate (MMA/nBA) monomer unit boundaries of phospholipids at p-MMA/nBA copolymer surfaces.

Science.gov (United States)

Yu, Min; Urban, Marek W; Sheng, Yinghong; Leszczynski, Jerzy

2008-09-16

Lipid structural features and their interactions with proteins provide a useful vehicle for further advances in membrane proteins research. To mimic one of potential lipid-protein interactions we synthesized poly(methyl methacrylate/ n-butyl acrylate) (p-MMA/nBA) colloidal particles that were stabilized by phospholipid (PLs). Upon the particle coalescence, PL stratification resulted in the formation of surface localized ionic clusters (SLICs). These entities are capable of recognizing MMA/nBA monomer interfaces along the p-MMA/nBA copolymer backbone and form crystalline SLICs at the monomer interface. By utilizing attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy and selected area electron diffraction (SAD) combined with ab initio calculations, studies were conducted that identified the origin of SLICs as well as their structural features formed on the surface of p-MMA/nBA copolymer films stabilized by 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) PL. Specific entities responsible for SLIC formation are selective noncovalent bonds of anionic phosphate and cationic quaternary ammonium segments of DLPC that interact with two neighboring carbonyl groups of nBA and MMA monomers of the p-MMA/nBA polymer backbone. To the best of our knowledge this is the first example of molecular recognition facilitated by coalescence of copolymer colloidal particles and the ability of PLs to form SLICs at the boundaries of the neighboring MMA and nBA monomer units of the p-MMA/nBA chain. The dominating noncovalent bonds responsible for the molecular recognition is a combination of H-bonding and electrostatic interactions.

MMA, A Computer Code for Multi-Model Analysis

Science.gov (United States)

Poeter, Eileen P.; Hill, Mary C.

2007-01-01

This report documents the Multi-Model Analysis (MMA) computer code. MMA can be used to evaluate results from alternative models of a single system using the same set of observations for all models. As long as the observations, the observation weighting, and system being represented are the same, the models can differ in nearly any way imaginable. For example, they may include different processes, different simulation software, different temporal definitions (for example, steady-state and transient models could be considered), and so on. The multiple models need to be calibrated by nonlinear regression. Calibration of the individual models needs to be completed before application of MMA. MMA can be used to rank models and calculate posterior model probabilities. These can be used to (1) determine the relative importance of the characteristics embodied in the alternative models, (2) calculate model-averaged parameter estimates and predictions, and (3) quantify the uncertainty of parameter estimates and predictions in a way that integrates the variations represented by the alternative models. There is a lack of consensus on what model analysis methods are best, so MMA provides four default methods. Two are based on Kullback-Leibler information, and use the AIC (Akaike Information Criterion) or AICc (second-order-bias-corrected AIC) model discrimination criteria. The other two default methods are the BIC (Bayesian Information Criterion) and the KIC (Kashyap Information Criterion) model discrimination criteria. Use of the KIC criterion is equivalent to using the maximum-likelihood Bayesian model averaging (MLBMA) method. AIC, AICc, and BIC can be derived from Frequentist or Bayesian arguments. The default methods based on Kullback-Leibler information have a number of theoretical advantages, including that they tend to favor more complicated models as more data become available than do the other methods, which makes sense in many situations. Many applications of MMA will

Preparation of PBA-P(MMA-DMA) core-shell latex particles%PBA-P（MMA-DMA）核壳乳胶粒子的制备

Institute of Scientific and Technical Information of China (English)

辛丹丹; 刘喜军; 娄春华

2016-01-01

A novel poly-butyl methacry1ate(PBA)-poly(methyl methacrylate-dimethylaminoethyl methacrylate)[P(MMA-DMA)]core-shell latex particle containing amino groups in surface layer was prepared by a pre-emulsion semi-continuous seeded emulsion polymerization method. It was characterized through element analyzer, laser particle size analyzer, transmission electron microscope (TEM), and X-ray Photoelectron Spectroscopy(XPS). The results indicate that PBA-P(MMA-DMA)latex particles are well-defined core-shell structure, and the mean grain size of PBA core and PBA-P(MMA-DMA) core-shell latex particles are 270 nm and 340 nm respectively. There exists DMA in shell layer of PBA-P (MMA-DMA) core-shell latex particles. When DMA content in shell layer is 10.0% of MMA, the mass fraction of nitrogen in PBA- P(MMA-DMA) core-shell latex particles reaches 0.29%, equivalent of 0.78% amino in shell layer.%采用预乳化半连续种子乳液聚合方法制备了一种新型的表层含氨基的聚甲基丙烯酸丁酯（PBA）-聚（甲基丙烯酸甲酯-甲基丙烯酸二甲氨基乙酯）[P（MMA-DMA）]核壳乳胶粒子，并通过激光粒径分析仪、透射电子显微镜、X射线光电子能谱仪和元素分析仪等对其进行表征。结果表明：PBA-P（MMA-DMA）乳胶粒子为核壳结构，PBA核芯和PBA-P（MMA-DMA）核壳乳胶粒子的平均粒径分别为270，340nm；PBA-P（MMA-DMA）核壳乳胶粒子的壳层确实含有甲基丙烯酸二甲氨基乙酯（DMA），当DMA用量为甲基丙烯酸甲酯质量的10.0%时，PBA-P（MMA-DMA）核壳乳胶粒子氮元素质量分数达0.29%，折合壳层氨基质量分数达0.78%。

Prenatal diagnosis of methymalonic aciduria and homocystinuria cblC type using DNA analysis

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Antonietta Zappu

2015-12-01

Full Text Available Methylmalonic aciduria (MMA and homocystinuria, cblC type is the most frequent inborn error of vitamin B12. CblC patients present with a heterogeneous clinical picture.To date, the early prenatal diagnosis of MMA and homocystinuria, cblC type is performed by determination of methylmalonic acid and total homocysteine (Hcy in amniotic fluid supernatant. In this paper we report a case of prenatal diagnosis, using genetic analysis, of MMA and homocystinuria, cblC type in an at risk couple. Direct sequencing analysis of the amplified products of chorionic villi biopsy extracted DNA showed normal sequence in the fetal DNA. Mutation analysis of the MMACHC gene is more cost-effective and less time-consuming than the biochemical approach. Early prenatal treatment may have an impact on the long-term complications associated with cblC disease. Future studies with the aim of determining the long-term benefits of daily parenteral OHCbl started soon after conception in at risk mothers should be considered. In this context early prenatal diagnosis could determine whether therapy needs to be continued.

Carglumic acid enhances rapid ammonia detoxification in classical organic acidurias with a favourable risk-benefit profile : a retrospective observational study

NARCIS (Netherlands)

Valayannopoulos, Vassili; Baruteau, Julien; Delgado, Maria Bueno; Cano, Aline; Couce, Maria L; Del Toro, Mireia; Donati, Maria Alice; Garcia-Cazorla, Angeles; Gil-Ortega, David; Gomez-de Quero, Pedro; Guffon, Nathalie; Hofstede, Floris C; Kalkan-Ucar, Sema; Coker, Mahmut; Lama-More, Rosa; Martinez-Pardo Casanova, Mercedes; Molina, Agustin; Pichard, Samia; Papadia, Francesco; Rosello, Patricia; Plisson, Celine; Le Mouhaer, Jeannie; Chakrapani, Anupam

2016-01-01

BACKGROUND: Isovaleric aciduria (IVA), propionic aciduria (PA) and methylmalonic aciduria (MMA) are inherited organic acidurias (OAs) in which impaired organic acid metabolism induces hyperammonaemia arising partly from secondary deficiency of N-acetylglutamate (NAG) synthase. Rapid reduction in

Performance evaluation of the Personal Mobility and Manipulation Appliance (PerMMA).

Science.gov (United States)

Wang, Hongwu; Xu, Jijie; Grindle, Garrett; Vazquez, Juan; Salatin, Ben; Kelleher, Annmarie; Ding, Dan; Collins, Diane M; Cooper, Rory A

2013-11-01

The Personal Mobility and Manipulation Appliance (PerMMA) is a recently developed personal assistance robot created to provide people with severe physical disabilities enhanced assistance in both mobility and manipulation. PerMMA aims to improve functional independence when a personal care attendant is not available on site. PerMMA integrates both a smart powered wheelchair and two dexterous robotic arms to assist its users in completing essential mobility and manipulation tasks during basic and instrumental activities of daily living (ADL). Two user interfaces were developed: a local control interface and a remote operator controller. This paper reports on the evaluation of PerMMA with end users completing basic ADL tasks. Participants with both lower and upper extremity impairments (N=15) were recruited to operate PerMMA and complete up to five ADL tasks in a single session of no more than two hours (to avoid fatigue or frustration of the participants). The performance of PerMMA was evaluated by participants completing ADL tasks with two different control modes: local mode and cooperative control. The users' task completion performance and answers on pre/post-evaluation questionnaires demonstrated not only the ease in learning and usefulness of PerMMA, but also their attitudes toward assistance from advanced technology like PerMMA. As a part of the iterative development process, results of this work will serve as supporting evidence to identify design criteria and other areas for improvement of PerMMA. Copyright © 2013 IPEM. All rights reserved.

Radiation-induced grafting polymerization of MMA onto polybutadiene rubber latex

International Nuclear Information System (INIS)

Peng Jing; Wang Maolin; Qiao Jinliang; Wei Genshuan

2005-01-01

The grafting of methyl methacrylate (MMA) onto polybutadiene rubber latex by the direct radiation method was carried out. The effects of monomer concentration, absorbed dose and dose rate of gamma rays on the grafting yield were investigated. The graft copolymers were characterized by transmission electron microscopy (TEM), FTIR spectroscopy, and differential scanning calorimetry. TEM photographs revealed that the core-shell structures of latex particles are formed at low MMA content, and with the increasing of MMA content, the semi-IPN-like structure with core-shell could be developed due to the high gel fraction of polybutadiene (PBD) seed particles. In addition, infrared analysis confirmed that MMA could be grafted onto PBD molecular chains effectively under appropriate irradiation conditions. The interfacial adhesion between PBD rubber (core) and PMMA (shell) phases could be enhanced with the increase of MMA concentration

Initiation of MMA polymerization by iniferters based on dithiocarbamates

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Jovanović Slobodan M.

2005-01-01

Full Text Available Twelve modified dithiocarbamates and a thiuramdisulfide used for the initiation of methyl methacrylate (MMA polymerization were synthesized in this study. The polymerization of MMA was followed by determine the yield and molar mass of the obtained PMMA as a function of polymerization time. Four of the synthesized dithiocarbamates S-benzyl-N,N-dibenzyldithiocarbamate, S-allyl-N,N-dibenzyldithiocarbamate S-benzyl-N,N-diisobutyldithiocarbamate and S-benzoyl-N,N-diisobutyldithiocarbamate, as well as N,N,N',N'-tetrabenzylthiuramdisulfide acted as iniferters. They were active as the initiators of the photo and/or thermally initiated radical polymerization of MMA in bulk and inert solvents (benzene and toluene. S Benzyl - N,N - dibenzyldithiocarbamate can be successfully used for the initiation of MMA polymerization in a polar solvent such as dimethylacetamide.

Methylmalonic aciduria and propionic acidaemia studied by proton nuclear magnetic resonance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Iles, R A; Hind, A J; Chalmers, R A

1986-12-15

Proton nuclear magnetic resonance spectroscopy has been used to monitor changes in urinary metabolites in a patient with propionic acidaemia over a period of 10 months and in a patient with methylmalonic aciduria over a period of 11 days. Results could be obtained within 5-10 min of sample receipt. In the spectra on the patient with propionic acidaemia not only could fluctuations in 3-hydroxypropionate and propionylglycine excretion be followed, but also variations in creatine, glycine and betaine, which were often present at millimolar concentrations. The patient with methylmalonic aciduria had an acute episode of severe ketoacidosis during which the glycine excretion fell but creatine excretion rose and then fell on recovery from the episode. The changes in the creatine excretion may reflect disorders in intracellular energy supply. Nuclear magnetic resonance is a powerful technique for monitoring metabolic perturbations in the organic acidurias in 'real-time', allowing the planning and evaluation of therapy. (Auth.). 18 refs.; 4 figs.; 3 tabs.

Methylmalonic aciduria and propionic acidaemia studied by proton nuclear magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Iles, R.A.; Hind, A.J.; Chalmers, R.A.

1986-01-01

Proton nuclear magnetic resonance spectroscopy has been used to monitor changes in urinary metabolites in a patient with propionic acidaemia over a period of 10 months and in a patient with methylmalonic aciduria over a period of 11 days. Results could be obtained within 5-10 min of sample receipt. In the spectra on the patient with propionic acidaemia not only could fluctuations in 3-hydroxypropionate and propionylglycine excretion be followed, but also variations in creatine, glycine and betaine, which were often present at millimolar concentrations. The patient with methylmalonic aciduria had an acute episode of severe ketoacidosis during which the glycine excretion fell but creatine excretion rose and then fell on recovery from the episode. The changes in the creatine excretion may reflect disorders in intracellular energy supply. Nuclear magnetic resonance is a powerful technique for monitoring metabolic perturbations in the organic acidurias in 'real-time', allowing the planning and evaluation of therapy. (Auth.)

Striking dynamics and kinetic properties of boxing and MMA gloves

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Benjamin Lee

2014-08-01

Full Text Available With the growing popularity of Mixed Martial Arts (MMA as a competitive sport, questions regarding the dynamic response and properties of MMA gloves arise. High-energy impacts from punches are very similar to boxing yet MMA competition requires the use of 4 oz fingerless glove, compared to the larger full enclosure boxing glove. This work assessed the kinetic properties and strike dynamics of MMA gloves and compared findings with traditional boxing gloves. Gloves mounted on a molded fist were impacted repetitively on an instrumental anvil designed for impact, over a 5 hour period resulting in 10,000 continuous and consistent strikes. Kinetic data from impacts were sampled at the beginning of the data collection and subsequently every 30 minutes (every 1,000 strikes. MMA gloves produced 4-5 times greater peak force and 5 times faster load rate compared to the boxing glove. However, MMA gloves also showed signs of material fatigue, with peak force increasing by 35% and rate of loading increasing by 60% over the duration of the test. Boxing glove characteristics did deteriorate but to a lesser extent. In summary, the kinetic properties of MMA glove differed substantially from the boxing glove resulting in impacts characterized by higher peak forces and more rapid development of force. Material properties including stiffness and thickness play a role in the kinetic characteristics upon impact, and can be inferred to alter injury mechanisms of blunt force trauma.

The Preparation and Characterization of Tourmaline-Containing Functional Copolymer p (VST/MMA/BA

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Yingmo Hu

2018-01-01

Full Text Available Tourmaline was modified with vinyl triethoxysilane containing double bond to prepare the polymerizable organic vinylsiliconoxyl tourmaline (VST and then copolymerized with methyl methacrylate (MMA and butyl acrylate (BA to produce the tourmaline-containing functional copolymer p (VST/MMA/BA. The structures and morphologies of VST and p (VST/MMA/BA copolymer were characterized by IR, SEM, and EDX. The experimental results indicated that tourmaline was introduced into the copolymer via surface modification and the tourmaline-containing functional copolymer was obtained by a copolymerization process with MMA and BA. The prepared p (VST/MMA/BA copolymer displayed excellent storage stabilities, high far-infrared radiation and negative ion releasing performances, and good mechanical properties.

Concurrent non-ketotic hyperglycinemia and propionic acidemia in an eight year old boy

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Paul S. Kruszka

2014-01-01

Full Text Available This is the first reported case of a patient with both non-ketotic hyperglycinemia and propionic acidemia. At 2 years of age, the patient was diagnosed with non-ketotic hyperglycinemia by elevated glycine levels and mutations in the GLDC gene (paternal allele: c.1576_1577insC delT and c.1580delGinsCAA; p.S527Tfs*13, and maternal allele: c.1819G>A; p.G607S. At 8 years of age after having been placed on ketogenic diet, he became lethargic and had severe metabolic acidosis with ketonuria. Urine organic acid analysis and plasma acylcarnitine profile were consistent with propionic acidemia. He was found to have an apparently homozygous mutation in the PCCB gene: c.49C>A; p.Leu17Met. The patient was also treated with natural protein restriction, carnitine, biotin, and thiamine and had subjective and biochemical improvement.

Diagnosis of propionic acidemia by gas chromatography coupled to mass spectrometry in a case analysis

International Nuclear Information System (INIS)

Camayd Viera, Ivette; Robaina Jimenez, Zoe; Contreras Roura, Jiovanna

2011-01-01

Propionic acidemia is an inherited metabolic disease caused by a deficiency in the propionyl-CoA carboxilase, a biotin-dependent mitochondrial enzyme. The disorder is a clinically heterogeneous disease and one of the most frequently occurring organic acidurias. We report the first Cuban case with a severe form of propionic acidemia followed by acidosis and death. The diagnosis was carried out by gas chromatography coupled to mass spectrometry. Our aim is to highlight the importance of organic acids urine analysis as part of the first laboratory tests in undiagnosed seriously ill children. The definitive diagnosis is important as it serves as a clear guideline to establish a suitable treatment and allows geneticists to provide patients with a proper genetic counseling

Hypoattenuation of the basal nuclei as a sign of propionic acidemia

International Nuclear Information System (INIS)

Asenjo, M.; Moron, A.; Marti, M.; Dominguez, F.

1999-01-01

The hypoattenuation of the basal ganglia is an uncommon radiological finding that suggests a metabolic or hypoxic disorder. We report a case of propionic acidemia in a five-year-old boy, presenting as a symmetric hypoattenuation of the basal neclei. We discuss this and other causes of this radiological finding, as well as the possible mechanism and underlying pathology. (Author) 17 refs

Efficiency of acidemia correction on intermittent versus continuous hemodialysis in acute methanol poisoning

Czech Academy of Sciences Publication Activity Database

Zakharov, S.; Pelclová, D.; Navrátil, Tomáš; Běláček, J.; Latta, J.; Písař, M.; Rulíšek, J.; Lepš, J.; Zídek, P.; Kučera, C.; Boček, R.; Mazur, M.; Belik, Z.; Chalupa, J.; Talafa, V.; Kodras, K.; Nalos, D.; Sedlak, C.; Šenkyřík, M.; Šmíd, J.; Šálek, T.; Roberts, D. M.; Hovda, K. E.

2017-01-01

Roč. 55, č. 2 (2017), s. 123-132 ISSN 1556-3650 Institutional support: RVO:61388955 Keywords : Acidemia * continuous veno-venous hemodialysis * extended daily hemodialysis * intermittent hemodialysis * metabolic acidosis * methanol poisoning Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.677, year: 2016

[SUCLA2-related encephalomyopathic mitochondrial DNA depletion syndrome: a case report and review of literature].

Science.gov (United States)

Liu, Zhimei; Fang, Fang; Ding, Changhong; Wu, Husheng; Lyu, Junlan; Wu, Yun

2014-11-01

To analyze the clinical characteristics of SUCLA2-related encephalomyopathic mitochondrial DNA depletion syndrome (MDS) in one patient, and review the latest clinical research reports. Clinical, laboratory and genetic data of one case of SUCLA2-related encephalomyopathic MDS diagnosed by department of Neurology, Beijing Children's Hospital in November, 2013 were reported, and through taking "SUCLA2" as key words to search at CNKI, Wanfang, PubMed and the Human Gene Mutation Database (HGMD) professional to date, the clinical characteristics of 24 reported cases of SUCLA2-related encephalomyopathic MDS in international literature in combination with our case were analyzed. (1) The patient was 5 years and 9 months old, born as a term small for gestational age infant whose birth weight was 2 400 g, and presented since birth with severe muscular hypotonia, feeding difficulties, failure to thrive, psychomotor retardation and hearing impairment. Until now, he still showed severe developmental retardation, together with muscular atrophy, thoracocyllosis and scoliosis, and facial features. The patient is the first born from consanguineous healthy parents, whose relationship is cousins. Laboratory tests showed urinary excretion of mild methylmalonic acid (MMA), elevated plasma lactate concentration, and increased C3-carnitine and C4-dicarboxylic-carnitine in plasma carnitine ester profiling. MRI showed brain atrophy-like and bilateral T2 hyperintensities in bilateral caudate nuclei and putamen. By Next-Generation Sequencing (NGS), we identified a novel homozygous missense mutation (c.970G > A) in the SUCLA2 in a highly conserved amino acid residue. (2) The total number was only 25 with a male to female ratio of 14: 11, and age of onset of 23 was 0-4 months. The most common clinical features in patients with SUCLA2 mutation were permanent hypotonia, muscle atrophy, psychomotor retardation and scoliosis or kyphosis. Frequent signs included hearing impairment, hyperkinesia

Particle morphology as a control of permeation in polymer films obtained from MMA/nBA colloidal dispersions.

Science.gov (United States)

Lestage, David J; Urban, Marek W

2004-07-20

The combination of precision-controlled weight loss measurements and spectroscopic surface FT-IR analysis allowed us to identify unique behaviors of poly(methyl methacrylate) (p-MMA). When MMA and n-butyl acrylate (nBA) are polymerized into p-MMA and p-nBA homopolymer blends, MMA/nBA random copolymers, and p-MMA/p-nBA core-shell morphologies, a controlled mobility and stratification of low molecular weight components occurs in films formed from coalesced colloidal dispersions. Due to different affinities toward water, p-MMA and p-nBA are capable of releasing water at different rates, depending upon particle morphological features of initial dispersions. As coalescence progresses, water molecules are released from the high free volume p-nBA particles, whereas p-MMA retains water molecules for the longest time due to its hydrophilic nature. As a result, water losses at extended coalescence times are relatively small for p-MMA. MMA/nBA copolymer and p-MMA/p-nBA blends follow the same trends, although the magnitudes of changes are not as pronounced. The p-MMA/p-nBA core-shell behavior resembles that of p-nBA homopolymer, which is attributed to significantly lower content of the p-MMA component in particles. Annealing of coalesced colloidal films at elevated temperatures causes migration of SDOSS to the F-A interface, but for films containing primarily p-nBA, reverse diffusion back into the bulk is observed. These studies illustrate that the combination of different particle morphologies and temperatures leads to controllable permeation processes through polymeric films. Copyright 2004 American Chemical Society

PHOTOPOLYMERIZATION OF MMA INITIATED BY CYANINE DYE AND HEXAARYLBIIMIDAZOLE

Institute of Scientific and Technical Information of China (English)

无

1998-01-01

The photoinitiating system composed of 1-ethyl-3'-methyl thiacyanine bromide (C-I), 2-chlorohexaarylbiimidazole (o-Cl-HABI) and 3-mercapto-4-methyl-4H-1, 2, 4-triazole (MTA), which act as sensitizer, initiator and hydrogen-donor respectively, can be used to initiate the polymerization of methyl methacrylate (MMA). The kinetic study was carried out in trichloromathane solution at 30℃ by using dilatometry. The relation between the polymerization rate and the concentrations of C-I, o-Cl-HABI, MTA and MMA was studied.

Preparation of poly(BMA-co-MMA) particles by soap-free emulsion polymerization and its optical properties as photonic crystals.

Science.gov (United States)

Lee, Ki-Chang; Choo, Hun-Seung

2014-11-01

Narrowly dispersed poly(BMA-co-MMA) and PBMA latices with particle diameters ranging within 216-435 nm were synthesized successfully by surfactant-free emulsion polymerization with KPS and AIBA. The average particle diameter and particle size distribution, average molecular weight and its distribution, glass transition temperature, reflectance spectra in visible wavelength, and refractive indices for the respective poly(BMA-co-MMA) latices and their photonic crystals were systematically investigated in terms of BMA/MMA ratio, BMA content, polymerization temperature, and DVB effect. The rate of polymerization increased with increasing MMA concentration in BMA/MMA ratio. The particle diameter increased with BMA concentration in BMA/MMA ratio. The molecular weight increased with BMA concentration in BMA/MMA ratio and monomer concentration. The drying of the latices offered self-assembled shiny colloidal crystal films showing the characteristic structural colors in visible wavelength. All the poly(BMA-co-MMA) latices prepared in the study were fallen within the range of photonic grade microspheres. The reflectance measurement on the colloidal photonic crystals having different particle diameters clearly exhibited narrow stopbands. The reflection maxima (λ(max)) measured in this study were well close to the λ(max) calculated, derived from the Bragg's equation. The refractive indices of poly(BMA-co-MMA) photonic crystals were found to be almost same as the theoretical values and increased proportionally from 1.50 to 1.57 with BMA content in BMA/MMA ratios. It was, thus, found that the optical reflectance properties of the poly(BMA-co-MMA) colloidal photonic crystals can be controlled easily by adjusting the reaction conditions and BMA/MMA ratio in soap-free emulsion copolymerization of BMA and MMA.

Synthesis and Characterization of Multiwalled Carbon Nanotubes/Poly(HEMA-co-MMA) by Utilizing Click Chemistry.

Science.gov (United States)

Bach, Long Giang; Cao, Xuan Thang; Islam, Md Rafiqul; Jeong, Yeon Tae; Kim, Jong Su; Lim, Kwon Taek

2016-03-01

The hybrid material consisting of multi walled carbon nanotubes (MWNTs) and poly(2-hydroxyethylmethacrylate-co-methylmethacrylate) [poly(HEMA-co-MMA)] was synthesized by a combination of RAFT and Click chemistry. In the primary stage, the copolymer poly(HEMA-co-MMA) was prepared by applying RAFT technique. Alkynyl side groups were incorporated onto the poly(HEMA-co-MMA) backbone by esterification reaction. Then, MWNTs-N3 was prepared by treating MWNTs with 4-azidobutylamine. The click coupling reaction between azide-functionalized MWNTs (MWNTs-N3) and the alkyne-functionalized random copolymer ((HEMA-co-MMA)-Alkyne) with the Cu(I)-catalyzed [3+2] Huisgen cycloaddition afforded the hybrid compound. The structure and properties of poly(MMA-co-HEMA)-g-MWNTs were investigated by FT-IR, EDX and TGA measurements. The copolymer brushes were observed to be immobilized onto the functionalized MWNTs by SEM and TEM analysis.

Study on radiation grafting reaction of MMA onto hydroxyapatite

International Nuclear Information System (INIS)

Jiang Bo

1996-01-01

The grafting reaction of MMA onto hydroxyapatite has been studied with the pre-irradiation method in air. The effects of radiation dose, monomer concentration, reaction temperature and inorganic acid on the system are observed. The grafting copolymerization is found to be controlled by the kinetics. If proper kinetic conditions are selected, a better grafting yield can be obtained. Employing weight method, burning method as well as SeM and IR analysis, it has been proved that MMA is definitely grafted onto hydroxyapatite by chemical bonds, which shows that it is possible to improve the interface of inorganic-organic composite materials and to make bioactive ceramics by using radiation induced-grafting copolymerization

Renal responses to prolonged (48 h) hypoxemia without acidemia in the late-gestation ovine fetus

NARCIS (Netherlands)

Dassel, ACM; Aarnoudse, JG

The effect of sustained moderate hypoxia on renal blood flow and renal function was studied in the ovine fetus (123-129 days). The experiments consisted of 48 h of isocapnic hypoxia, not resulting in acidemia, but sufficient to produce redistribution of blood flow in favor of the brain at the

Effect of solvents on properties of Bombyx mori silk grafted by methyl methacrylate (MMA and methacrylamide (MAA

Directory of Open Access Journals (Sweden)

Wattana Klairatsamee

2005-11-01

Full Text Available Mulberry silks were chemically modified in order to increase weight gain, resulting from degumming process using graft copolymerisation technique with vinyl monomers, i.e. MMA, MAA and MMA/MAA. Due to the appearance of PMMA homopolymer granules adhered on the MMA- and MMA/MAA-grafted silk surfaces resulting in surface roughness when silk was grafted by MMA in water, the influence of grafting solvents was examined, using different water/ethanol volume ratios of 100/0, 75/25, 50/50, 25/75 and 0/100. FTIR spectra of the grafted silks presented the absorption bands of the vinyl monomers used for the grafting process. In addition, high values of % polymer add-on were obtained for all of the grafted silks. It was also found that the suitable solvents were 25/75 water/ethanol for the silk grafted by MMA and MMA/MAA, and water for the silk grafted by MAA, in order to get the smooth grafted silk surface and high polymer add-on. Moreover, all the grafted silks showed slightly greater stiffness, as indicated by the increase of Young's modulus and the decrease of elongation.

Inborn Errors of Intermediary Metabolism in Critically Ill Mexican Newborns

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Ibarra-González Isabel MSc

2014-04-01

Full Text Available Inborn errors of intermediary metabolism (IEiM are complex diseases with high clinical heterogeneity, and some patients who have severe enzyme deficiencies or are subjected to stress (catabolism/infections actually decompensate in the neonatal period. In this study, we performed metabolic tests on 2025 newborns in Mexico admitted to 35 neonatal intensive care units or emergency wards (NICUs/EWs over a 6-year period, in whom a metabolic disorder was clinically suspected. Of these 2025 newborns with sickness, 11 had IEiM, revealing a prevalence of 1:184. Clinical characteristics and outcomes of the newborns with confirmed IEiM are shown. Of these 11 patients, 4 had isolated methylmalonic acidemia, 3 had maple syrup urine disease, 2 had urea cycle disorders, 1 had 3-hydroxy-3-methylglutaric acidemia, and 1 had isovaleric acidemia. During the first week of life (average 3 days, all of these newborns presented with impaired alertness, hypotonia, feeding difficulties, and vomiting along with metabolic acidosis and hyperammonemia. Of the 11 newborns with IEiM, 7 died, leading to a mortality rate of 64%. In conclusion, the differential diagnosis of newborns admitted to the NICU/EW must include IEiM, requiring systematic screening of this population.

An unusual cause of high anion gap metabolic acidosis: pyroglutamic acidemia. A case report.

Science.gov (United States)

Romero, Jorge E; Htyte, Nay

2013-01-01

Pyroglutamic acidemia is an uncommon metabolic disorder, which is usually diagnosed at early ages. The mechanism of action is thought to be glutathione depletion, and its clinical manifestations consist of hemolytic anemia, mental retardation, ataxia, and chronic metabolic acidosis. However, an acquired form has been described in adult patients, who usually present with confusion, respiratory distress, and high anion gap metabolic acidosis (HAGMA). It is also associated with many conditions, including chronic acetaminophen consumption. A 68-year-old white male, with chronic acetaminophen use presented to our service on multiple occasions with severe HAGMA. The patient was admitted to the intensive care unit and required mechanical ventilation and aggressive supportive measures. After ruling out the most frequent etiologies for his acid-base disorder and considering the long history of Tylenol ingestion, his 5-oxiproline (pyroglutamic acid) levels were sent to diagnose pyroglutamic acidemia. Clinicians need to be aware of this cause for metabolic acidosis since it might be a more common metabolic disturbance in compromised patients than would be expected. Subjects with HAGMA that cannot be explained by common causes should be tested for the presence of 5-oxoproline. Discontinuation of the offending drug is therapeutic.

Electrospinning of Poly (MMA-CO-Maa) Copolymers And Their Layered Silicate Nanocomposites For Improved Thermal Properties

Science.gov (United States)

2004-12-01

7518. Ho, B.C., Lee, Y.D. and Chin, W.K., 1992: Thermal Degradation of Polymethacrylic Acid , J. Polym. Sci., Polymer Chemistry, 30, 2389-2397. Lee...AMSRD-ARL-WM-MD Aberdeen Proving Ground, MD 21005-5069 ABSTRACT Copolymers consisting of methyl methacrylate (MMA) and methacrylic acid (MAA...from solution of poly (MMA-co-MAA) copolymer (50/50 weight ratio of MMA and methacrylic acid , MAA) in dimethylformamide (DMF) and the corresponding

Detection of vitamin B12 deficiency in older people by measuring vitamin B12 or the active fraction of vitamin B12, holotranscobalamin

DEFF Research Database (Denmark)

Clarke, Robert; Sherliker, Paul; Hin, Harold

2007-01-01

BACKGROUND: Impaired vitamin B(12) function and decreased vitamin B(12) status have been associated with neurological and cognitive impairment. Current assays analyze total vitamin B(12) concentration, only a small percentage of which is metabolically active. Concentrations of this active component......, carried on holotranscobalamin (holoTC), may be of greater relevance than total vitamin B(12). METHODS: We compared the utility of serum holoTC with conventional vitamin B(12) for detection of vitamin B(12) deficiency in a population-based study of older people, using increased methylmalonic acid (MMA......) concentrations as a marker of metabolic vitamin B(12) deficiency in the overall population (n = 2403) and in subsets with normal (n = 1651) and abnormal (n = 752) renal function. RESULTS: Among all participants, 6% had definite (MMA >0.75 micromol/L) and 16% had probable (MMA >0.45 micromol/L) metabolic vitamin...

Hypercapnea and Acidemia despite Hyperventilation following Endotracheal Intubation in a Case of Unknown Severe Salicylate Poisoning

Directory of Open Access Journals (Sweden)

Shannon M. Fernando

2017-01-01

Full Text Available Salicylates are common substances for deliberate self-harm. Acute salicylate toxicity is classically associated with an initial respiratory alkalosis, followed by an anion gap metabolic acidosis. The respiratory alkalosis is achieved through hyperventilation, driven by direct stimulation on the respiratory centers in the medulla and considered as a compensatory mechanism to avoid acidemia. However, in later stages of severe salicylate toxicity, patients become increasingly obtunded, with subsequent loss of airway reflexes, and therefore intubation may be necessary. Mechanical ventilation has been recommended against in acute salicylate poisoning, as it is believed to take away the compensatory hyperpnea and tachypnea. Despite the intuitive physiological basis for this recommendation, there is a paucity of evidence to support it. We describe a case of a 59-year-old male presenting with decreased level of consciousness and no known history of ingestion. He was intubated and experienced profound hypercarbia and acidemia despite mechanical ventilation with high minute ventilation and tidal volumes. This case illustrates the deleterious effects of intubation in severe salicylate toxicity.

A New Kind of Void Soap-free P(MMA-EA-MAA) Latex Particles

Institute of Scientific and Technical Information of China (English)

Kai KANG; Cheng You KAN; Yi DU; Yu Zhong LI; De Shan LIU

2005-01-01

Soap-free P(MMA-EA-MAA) particles with narrow size distribution were synthesized by seeded emulsion polymerization of methyl methacrylate (MMA), ethyl acrylate (EA) and methacrylic acid (MAA), and large voids inside the particles were generated by alkali posttreatment in the presence of 2-butanone. Results indicated that the size of void and the particle volume were related with the amount of 2-butanone. The generation mechanism of voids was proposed.

Cobalamin deficiency associated with erythroblastic anemia and methylmalonic aciduria in a border collie.

Science.gov (United States)

Morgan, L W; McConnell, J

1999-01-01

Anemia due to cobalamin deficiency is a rare genetic disorder that has been recognized in dogs only recently. This report concerns a 14-month-old border collie that presented for chronic, nonregenerative anemia. Cytological examination of a peripheral blood smear showed the presence of erythroblasts. Serum cobalamin levels were below reference ranges reported for clinically normal dogs. A methylmalonic aciduria was found on urinalysis. These signs are consistent with the anemia in Imerslund-Graesbeck syndrome reported in humans. Anemia due to cobalamin deficiency responds to parenteral vitamin B12 therapy, and affected animals have a good prognosis for recovery.

1H MR spectroscopy of the basal ganglia in childhood: a semiquantitative analysis

International Nuclear Information System (INIS)

Lam, W.W.M.; Zhao, H.; Berry, G.T.; Kaplan, P.; Gibson, J.; Kaplan, B.S.

1998-01-01

Proton MR spectra of the basal ganglia were obtained from 28 patients, 24 male and 14 female, median age 16.3 months (5 weeks to 31 years). They included 17 patients with normal MRI of the basal ganglia without metabolic disturbance (control group) and 11 patients with various metabolic diseases: one case each of high serum sodium and high serum osmolarity, cobalamin C deficiency, Leigh disease, Galloway-Mowat syndrome, Pelizaeus-Merzbacher disease, hemolytic-uremic syndrome and Wilson disease and two cases of Alagille syndrome and methylmalonic acidemia with abnormal MRI of the basal ganglia or blood or urine analysis (abnormal group). The MR spectrum was measured by using STEAM. The MR-visible water content of the region of interest was obtained. Levels of myoinositol, choline, creatine and N -acetylaspartate were measured using a semiquantitative approach, with absolute reference calibration. In the control group, there was a gradual drop of water content over the first year of life; N -acetylaspartate, creatine and myoinositol levels showed no significant change with age, in contrast to the occipital, parietal and cerebellar regions. Choline showed a gradual decrease for the first 2 years of life and then remained fairly constant. In the abnormal group the water content was not significantly different. N -Acetylaspartate was decreased in patients with high serum sodium and high serum osmolarity, cobalamin C deficiency, Leigh disease and one case of methylmalonic acidemia. Decreased creatine was also found in Leigh disease, and decreased choline in Galloway-Mowat syndrome and Wilson disease. Myoinositol was elevated in the patient with abnormally high serum sodium, and decreased in the hemolytic-uremic syndrome. (orig.)

Clinical characteristics of hemolytic uremic syndrome secondary to cobalamin C disorder in Chinese children.

Science.gov (United States)

Li, Qi-Liang; Song, Wen-Qi; Peng, Xiao-Xia; Liu, Xiao-Rong; He, Le-Jian; Fu, Li-Bing

2015-08-01

The present study was undertaken to investigate the clinical characteristics of hemolytic uremic syndrome (HUS) secondary to cobalamin C disorder (cbl-C disorder). We reviewed retrospectively the medical records of 3 children with HUS secondary to cbl-C disorder who had been treated between April 1, 2009 and October 31, 2013. The 3 patients with HUS secondary to cbl-C disorder presented with progressive hemolytic anemia, acute renal failure, thrombocytopenia, poor feeding, and failure to thrive. Two of the 3 patients once had high blood pressure. The mutations of c.609G>A (p.W203X), c.217C>T (p.R73X) and c.365A>T (p.H122L) in the methylmalonic aciduria (cobalamin deficiency) cbl-C type, with homocystinuria gene were detected in the 3 patients. In these patients the levels of lactate dehydrogenase and homocysteine in serum were elevated and the level of methylmalonic acid (MMA) in urine was also elevated. After treatment with hydroxocobalamin, 2 patients were discharged with no obvious abnormal growth and neurological development and 1 patient died of multiple organ failure. The results of this study demonstrated that cbl-C disorder should be investigated in any child presenting with HUS. The high concentrations of homocysteine and MMA could be used for timely recognization of the disease. Once the high levels of plasma homocystein and/or plasma or urine MMA are detected, the treatment with parenteral hydroxocobalamin should be prescribed immediately. The early diagnosis and treatment would contribute to the good prognosis of the disease.

Quantification of N-acetylcysteamine activated methylmalonate incorporation into polyketide biosynthesis

Directory of Open Access Journals (Sweden)

Stephan Klopries

2013-04-01

Full Text Available Polyketides are biosynthesized through consecutive decarboxylative Claisen condensations between a carboxylic acid and differently substituted malonic acid thioesters, both tethered to the giant polyketide synthase enzymes. Individual malonic acid derivatives are typically required to be activated as coenzyme A-thioesters prior to their enzyme-catalyzed transfer onto the polyketide synthase. Control over the selection of malonic acid building blocks promises great potential for the experimental alteration of polyketide structure and bioactivity. One requirement for this endeavor is the supplementation of the bacterial polyketide fermentation system with tailored synthetic thioester-activated malonates. The membrane permeable N-acetylcysteamine has been proposed as a coenzyme A-mimic for this purpose. Here, the incorporation efficiency into different polyketides of N-acetylcysteamine activated methylmalonate is studied and quantified, showing a surprisingly high and transferable activity of these polyketide synthase substrate analogues in vivo.

Mutation in mitochondrial complex IV subunit COX5A causes pulmonary arterial hypertension, lactic acidemia, and failure to thrive

NARCIS (Netherlands)

Baertling, F.; Al-Murshedi, F.; Sanchez Caballero, L.M.; Al-Senaidi, K.; Joshi, N.P.; Venselaar, H.; Brand, M.A.M. van den; Nijtmans, L.G.J.; Rodenburg, R.J.T.

2017-01-01

COX5A is a nuclear-encoded subunit of mitochondrial respiratory chain complex IV (cytochrome c oxidase). We present patients with a homozygous pathogenic variant in the COX5A gene. Clinical details of two affected siblings suffering from early-onset pulmonary arterial hypertension, lactic acidemia,

Central Venous Catheter-Related Bloodstream Infection with Kocuria kristinae in a Patient with Propionic Acidemia

OpenAIRE

Kimura, Masato; Kawai, Eichiro; Yaoita, Hisao; Ichinoi, Natsuko; Sakamoto, Osamu; Kure, Shigeo

2017-01-01

Kocuria kristinae is a catalase-positive, coagulase-negative, Gram-positive coccus found in the environment and in normal skin and mucosa in humans; however, it is rarely isolated from clinical specimens and is considered a nonpathogenic bacterium. We describe a case of catheter-related bacteremia due to K. kristinae in a young adult with propionic acidemia undergoing periodic hemodialysis. The patient had a central venous catheter implanted for total parenteral nutrition approximately 6 mont...

PE-g-MMA polymer electrolyte membrane for lithium polymer battery

Energy Technology Data Exchange (ETDEWEB)

Gao Kun [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)]. E-mail: gaokun@hit.edu.cn; Hu Xinguo [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Yi Tingfeng [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Dai Changsong [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

2006-10-25

PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF{sub 6}-EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10{sup -3} S cm{sup -1} at the DG of 42%. Compared with those containing PE separators, the LiCoO{sub 2}-MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance.

PE-g-MMA polymer electrolyte membrane for lithium polymer battery

International Nuclear Information System (INIS)

Gao Kun; Hu Xinguo; Yi Tingfeng; Dai Changsong

2006-01-01

PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF 6 -EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10 -3 S cm -1 at the DG of 42%. Compared with those containing PE separators, the LiCoO 2 -MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance

PE-g-MMA polymer electrolyte membrane for lithium polymer battery

Energy Technology Data Exchange (ETDEWEB)

Gao, Kun; Hu, Xinguo; Yi, Tingfeng; Dai, Changsong [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

2006-10-25

PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF{sub 6}-EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10{sup -3}Scm{sup -1} at the DG of 42%. Compared with those containing PE separators, the LiCoO{sub 2}-MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance. (author)

Design of starch functionalized biodegradable P(MAA-co-MMA) as carrier matrix for l-asparaginase immobilization.

Science.gov (United States)

Ulu, Ahmet; Koytepe, Suleyman; Ates, Burhan

2016-11-20

We prepared biodegradable P(MAA-co-MMA)-starch composite as carrier matrix for the immobilization of l-asparaginase (l-ASNase), an important chemotherapeutic agent in acute lymphoblastic leukemia. Chemical characteristics and thermal stability of the prepared composites were determined by FT-IR, TGA, DTA and, DSC, respectively. Also, biodegradability measurements of P(MAA-co-MMA)-starch composites were carried out to examine the effects of degradation of the starch. Then, l-ASNase was immobilized on the P(MAA-co-MMA)-starch composites. The surface morphology of the composite before and after immobilization was characterized by SEM, EDX, and AFM. The properties of the immobilized l-ASNase were investigated and compared with the free enzyme. The immobilized l-ASNase had better showed thermal and pH stability, and remained stable after 30days of storage at 25°C. Thus, based on the findings of the present work, the P(MAA-co-MMA)-starch composite can be exploited as the biocompatible matrix used for l-ASNase immobilization for medical applications due to biocompatibility and biodegradability. Copyright © 2016 Elsevier Ltd. All rights reserved.

STUDY ON THE KINETICS OF POLYMERIZATION OF MMA BY COPPER（Ⅱ） CHELATING RESINS

Institute of Scientific and Technical Information of China (English)

WangHongzuo; JiangYuanzhang; 等

1993-01-01

The polymerization of MMA initiated by copper(Ⅱ） chelating resins/CCl4 system was studied.From the kinetic data,the kinetic equation of polymerization can be expressed as Rp=Ke-56400/RT[MMA]1.57[CCl4]m[RESIN-Cu]0.18 where m:3-4.5,when[CCl4] 0.1-6.93M.The free radical polymerization mechanism is proposed.The primary radicals are formed by the process of complexation-chlorine transformation among the copper(Ⅱ) chelating resin,CCl4 and methacrylate.

P(AN-MMA)/TiO_2 Nano-composite Polymer Electrolyte by in-situ Polymerization

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

1 Introduction With the development of portable electric devices,polymer lithium ion batteries (PLiBs) have been widely used as the power sources because of their high energy density and safe property[1].P(AN-MMA) copolymer is a kind of cheap macromolecules easily dissolving in the polar solvents such as carbonate,it has been applied as gel polymer electrolyte in PLiBs.Here we prepare a kind of highly conductive nano-composite polymer electrolytes using the P(AN-MMA) copolymer incorporated with TiO2 nan...

STUDY ON THE POLYMERIZATION KINETICS AND STABILITY OF P(UA)/MMA MICROEMULSION

Institute of Scientific and Technical Information of China (English)

Hong-tao Zhang; Tian-bin Ren; Zhao-hui Yin

2001-01-01

Urethane acrylate anionomer (APUA) as a kind of new type polymerizable emulsifier was synthesized using 2,4-toluene diisocyanate (TDI), polypropylene glycol (PPG), 2-hydroxyethyl methacrylate (HEMA) and dimethylolpropionic acid (DMPA). The critical micelle concentration (CMC) of APUA was measured by the methods of conductance and surface tension. The comparative studies between polymerizable emulsifier AUPA and conventional emulsifier sodium dodecyl sulfate (SDS) were carried out in the emulsion polymerization of methyl methacrylate (MMA). Polymerization kinetics,stability, size and morphology of the latex particles were investigated. It was found that in APUA both water soluble initiator potassium persulfate (KPS) and oil soluble initiator 2,2'-azobisisobutyronitrile (AIBN) can start the reaction of MMA, and the polymerization rate and yield were very high. On using AIBN as an initiator, the conversion-time behavior of MMA with APUA as emulsifier was different to that of SDS as emulsifier, signifying a different nucleation mechanism of the polymer latex particle. The average size of the two kinds of particles is about 50 nm. The particle size decreases with increasing emulsifier concentration. On using KPS as the initiator, APUA as emulsifier, cross-linking hydrogel of PMMA would be formed, but SDS was used as emulsifier and the hydrogel of PMMA was not present.

Effects of mass fraction of monomer on emulsion polymerization nucleation of methyl methacrylate%w(MMA)对MMA乳液聚合成核的影响

Institute of Scientific and Technical Information of China (English)

成涛涛; 孙彦琳; 何艳萍; 王红; 肖小琴; 许冰文

2015-01-01

以甲基丙烯酸甲酯(MMA)为单体,在c(乳化剂)=2 mmol/L下制备乳液,研究不同w(MMA)对MMA乳液聚合成核的影响,并分析了不同w(MMA)对乳胶粒粒径的影响规律.实验结果表明:当w(MMA)≤10％,随着w(MMA)的增加转化率逐渐增大,乳胶粒的生成速率也逐渐增大;当w(MMA)≥10％时,转化率可以达到70％以上,w(MMA)对乳胶粒的生成速率的影响不大,多余的单体用于乳胶粒粒径的增长;在w(MMA)=10％时基本能够满足c(乳化剂)=2 mmol/L时的成核要求.当5％≤w(MMA)≤30％,在乳化剂的自调节作用下,使得最终形成的乳胶粒数目相差不大.

Reactive oxygen species-dependent HSP90 protein cleavage participates in arsenical As+3- and MMA+3-induced apoptosis through inhibition of telomerase activity via JNK activation

International Nuclear Information System (INIS)

Shen, S.-C.; Yang, L.-Y.; Lin, H.-Y.; Wu, C.-Y.; Su, T.-H.; Chen, Y.-C.

2008-01-01

The effects of six arsenic compounds including As +3 , MMA +3 , DMA +3 , As +5 , MMA +5 , and DMA +5 on the viability of NIH3T3 cells were examined. As +3 and MMA +3 , but not the others, exhibited significant cytotoxic effects in NIH3T3 cells through apoptosis induction. The apoptotic events such as DNA fragmentation and chromosome condensation induced by As +3 and MMA +3 were prevented by the addition of NAC and CAT, and induction of HO-1 gene expression in accordance with cleavage of the HSP90 protein, and suppression of telomerase activity were observed in NIH3T3 cells under As +3 and MMA +3 treatments. An increase in the intracellular peroxide level was examined in As +3 - and MMA +3 -treated NIH3T3 cells, and As +3 - and MMA +3 -induced apoptotic events were blocked by NAC, CAT, and DPI addition. HSP90 inhibitors, GA and RD, significantly attenuated the telomerase activity in NIH3T3 cells with an enhancement of As +3 - and MMA +3 -induced cytotoxicity. Suppression of JNKs significantly inhibited As +3 - and MMA +3 -induced apoptosis by blocking HSP90 protein cleavage and telomerase reduction in NIH3T3 cells. Furthermore, Hb, SnPP, and dexferosamine showed no effect against As +3 - and MMA +3 -induced apoptosis, and overexpression of HO-1 protein or inhibition of HO-1 protein expression did not affect the apoptosis induced by As +3 or MMA +3 . These data provide the first evidence to indicate that apoptosis induced by As +3 and MMA +3 is mediated by an ROS-dependent degradation of HSP90 protein and reduction of telomerase via JNK activation, and HO-1 induction might not be involved

Multiple model analysis with discriminatory data collection (MMA-DDC): A new method for improving measurement selection

Science.gov (United States)

Kikuchi, C.; Ferre, P. A.; Vrugt, J. A.

2011-12-01

Hydrologic models are developed, tested, and refined based on the ability of those models to explain available hydrologic data. The optimization of model performance based upon mismatch between model outputs and real world observations has been extensively studied. However, identification of plausible models is sensitive not only to the models themselves - including model structure and model parameters - but also to the location, timing, type, and number of observations used in model calibration. Therefore, careful selection of hydrologic observations has the potential to significantly improve the performance of hydrologic models. In this research, we seek to reduce prediction uncertainty through optimization of the data collection process. A new tool - multiple model analysis with discriminatory data collection (MMA-DDC) - was developed to address this challenge. In this approach, multiple hydrologic models are developed and treated as competing hypotheses. Potential new data are then evaluated on their ability to discriminate between competing hypotheses. MMA-DDC is well-suited for use in recursive mode, in which new observations are continuously used in the optimization of subsequent observations. This new approach was applied to a synthetic solute transport experiment, in which ranges of parameter values constitute the multiple hydrologic models, and model predictions are calculated using likelihood-weighted model averaging. MMA-DDC was used to determine the optimal location, timing, number, and type of new observations. From comparison with an exhaustive search of all possible observation sequences, we find that MMA-DDC consistently selects observations which lead to the highest reduction in model prediction uncertainty. We conclude that using MMA-DDC to evaluate potential observations may significantly improve the performance of hydrologic models while reducing the cost associated with collecting new data.

Biochemical Differences Between Official and Simulated Mixed Martial Arts (MMA) Matches.

Science.gov (United States)

Silveira Coswig, Victor; Hideyoshi Fukuda, David; de Paula Ramos, Solange; Boscolo Del Vecchio, Fabricio

2016-06-01

One of the goals for training in combat sports is to mimic real situations. For mixed martial arts (MMA), simulated sparring matches are a frequent component during training, but a there is a lack of knowledge considering the differences in sparring and competitive environments. The main objective of this study was to compare biochemical responses to sparring and official MMA matches. Twenty five male professional MMA fighters were evaluated during official events (OFF = 12) and simulated matches (SIM = 13). For both situations, blood samples were taken before (PRE) and immediately after (POST) matches. For statistical analysis, two-way analysis of variance (time x group and time x winner) were used to compare the dependent parametric variables. For non-parametric data, the Kruskal-Wallis test was used and differences were confirmed by Mann-Whitney tests. No significant differences were observed among the groups for demographic variables. The athletes were 26.5 ± 5 years with 80 ± 10 kg, 1.74 ± 0.05 m and had 39.4 ± 25 months of training experience. Primary results indicated higher blood glucose concentration prior to fights for OFF group (OFF= 6.1 ± 1.2 mmol/L and SIM= 4.4 ± 0.7 mmol/L; P < 0.01) and higher ALT values for OFF group at both time points (OFF: PRE = 41.2 ± 12 U/L, POST = 44.2 ± 14.1 U/L; SIM: PRE = 28.1 ± 13.8 U/L, POST = 30.5 ± 12.5 U/L; P = 0.001). In addition, the blood lactate showed similar responses for both groups (OFF: PRE= 4 [3.4 - 4.4] mmol/L, POST= 16.9 [13.8 - 23.5] mmol/L; SIM: PRE = 3.8 [2.8 - 5.5] mmol/L, POST= 16.8 [12.3 - 19.2] mmol/L; P < 0.001). In conclusion, MMA official and simulated matches induce similar high intensity glycolytic demands and minimal changes to biochemical markers of muscle damage immediately following the fights. Glycolytic availability prior to the fights was raised exclusively in response to official matches.

Synthesis of Fluorinated Amphiphilic Block Copolymers Based on PEGMA, HEMA, and MMA via ATRP and CuAAC Click Chemistry

Directory of Open Access Journals (Sweden)

Fatime Eren Erol

2014-01-01

Full Text Available Synthesis of fluorinated amphiphilic block copolymers via atom transfer radical polymerization (ATRP and Cu(I catalyzed Huisgen 1,3-dipolar cycloaddition (CuAAC was demonstrated. First, a PEGMA and MMA based block copolymer carrying multiple side-chain acetylene moieties on the hydrophobic segment for postfunctionalization was carried out. This involves the synthesis of a series of P(HEMA-co-MMA random copolymers to be employed as macroinitiators in the controlled synthesis of P(HEMA-co-MMA-block-PPEGMA block copolymers by using ATRP, followed by a modification step on the hydroxyl side groups of HEMA via Steglich esterification to afford propargyl side-functional polymer, alkyne-P(HEMA-co-MMA-block-PPEGMA. Finally, click coupling between side-chain acetylene functionalities and 2,3,4,5,6-pentafluorobenzyl azide yielded fluorinated amphiphilic block copolymers. The obtained polymers were structurally characterized by 1H-NMR, 19F-NMR, FT-IR, and GPC. Their thermal characterizations were performed using DSC and TGA.

Relationship between cobalamin-dependent metabolites and both serum albumin and alpha1 -proteinase inhibitor concentrations in hypocobalaminemic dogs of 7 different breeds.

Science.gov (United States)

Grützner, Niels; Suchodolski, Jan S; Steiner, Jörg M

2014-12-01

Increased serum concentrations of homocysteine (HCY) and methylmalonic acid (MMA), the 2 main cobalamin-dependent metabolites, as well as decreased serum albumin and canine alpha1 -proteinase inhibitor (cα1 -PI) concentrations have previously been described in hypocobalaminemic dogs with gastrointestinal disease. However, no studies have been conducted to evaluate potential relationships between these serum biomarkers. The aim of this study was to evaluate the relationship between HCY and MMA, 2 cobalamin-dependent metabolites, and both serum albumin and cα1 -PI concentrations in hypocobalaminemic dogs. Serum samples from 285 dogs including 7 different breeds (Beagle, Boxer, Cocker Spaniel, German Shepherd, Labrador Retriever, Chinese Shar-Pei, and Yorkshire Terrier) with hypocobalaminemia were used. Serum HCY, MMA, albumin, and cα1 -PI concentrations were determined. There was a significant correlation between serum HCY and albumin concentrations, as well as serum HCY and cα1 -PI concentrations (ρ = 0.62 and ρ = 0.37, respectively; P  .05). In addition, significant breed-specific correlations were observed between serum MMA and albumin concentrations in German Shepherds, and serum HCY and MMA concentrations in Chinese Shar-Peis with hypocobalaminemia. This study shows a correlation between serum albumin and cα1 -PI and HCY concentrations, but not with serum MMA concentration in dogs with hypocobalaminemia. In addition, significant breed-specific correlations were observed between serum MMA and albumin concentrations in German Shepherds, as well as serum HCY and MMA concentrations in Chinese Shar-Peis, emphasizing the unique metabolic interactions in those dog breeds affected by hypocobalaminemia. © 2014 American Society for Veterinary Clinical Pathology.

Preparation of Fe3 O4 @ion imprinted poly(MMA-HPMA-DVB)magnetic composite and its selective adsorption to Ni(Ⅱ)%磁性Fe3O4@离子印迹聚(MMA-HPMA-DVB)复合材料的合成及其对水中Ni(Ⅱ)选择性吸附

Institute of Scientific and Technical Information of China (English)

王燕; 叶思; 吕珊珊; 张佳丽; 沈昊宇; 叶仙森

2017-01-01

采用超声协助悬浮聚合法以Ni(Ⅱ)离子为模板制备了氨基功能化纳米Fe3O4-离子印迹聚(甲基丙烯酸甲酯(MMA)-3-(2-氨基乙基胺)-2-甲基丙烯酸羟丙酯(HPMA)-二乙烯基苯(DVB))磁性复合材料(Fe3O4@ion im-printed poly(MMA-HPMA-DVB),Fe3 O4@IIP(MMA-HPMA-DVB)).通过EA、XRD、FTIR、TEM、VSM等手段对Fe3O4@IIP(MMA-HPMA-DVB)的组成、结构、形貌、磁性等进行了表征,并研究了其吸附水中Ni(Ⅱ)的性能.结果表明:合成的Fe3O4@IIP(MMA-HPMA-DVB)平均粒径为100 nm,饱和磁化强度为43.8 emu/g;共聚单体甲基丙烯酸甲酯(MMA)的羰基通过氢键与Fe3O4表面羟基结合,有利于Fe3O4@IIP(MMA-HPMA-DVB)的核-壳结构的形成与稳定;Fe3O4@IIP(MMA-HPMA-DVB)对Ni(Ⅱ)的吸附受溶液pH值影响较小;等温吸附线符合Langmuir模型,饱和吸附量(q m,c=500 mg/g,q m,e=478 mg/g)高于非离子印迹材料(Fe3 O4@none-ion imprinted poly(MMA-HPMA-DVB),Fe3 O4@NIP(MMA-HPMA-DVB)),q m,c=90.9 mg/g,q m,e=83.8 mg/g).吸附过程可在5 min内达到平衡,符合准二级动力学模型.Fe3 O4@IIP(MMA-HPMA-DVB)能高选择性地有效吸附水中Ni(Ⅱ),对Ni(Ⅱ)的印迹因子(α)为1.9,对几种常见共存离子的选择性因子(β)>7.7,是潜在的高选择性吸附和回收Ni(Ⅱ)的功能材料.%An amino-functionalized Fe3 O4-ion imprinted poly(methyl methacrylate (MMA)-3-(2-amino-ethylami-no)-2-hydroxypropyl methacrylate (HPMA)-divinylbenzene(DVB))magnetic composite (Fe3 O4 @ion imprinted po-ly(IIP)(MMA-HPMA-DVB))was synthesized via ultrasonic assisted suspension polymerization with nickel(Ⅱ)as ion imprinting template.The Fe3 O4 @IIP(MMA-HPMA-DVB)was characterized by EA,XRD,FTIR,TEM,TG and VSM.The application for its adsorption properties on Ni(Ⅱ)from water was investigated.The results show that the Fe3 O4 @IIP(MMA-HPMA-DVB)has an average size of 100 nm,with the saturation magnetization intensity of 43.8 emu/g.The carbonyl group of the co-monomer methyl methacrylate (MMA)can connect

Early Infantile Epileptic Encephalopathy in an STXBP1 Patient with Lactic Acidemia and Normal Mitochondrial Respiratory Chain Function

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Dong Li

2016-01-01

Full Text Available A wide range of clinical findings have been associated with mutations in Syntaxin Binding Protein 1 (STXBP1, including multiple forms of epilepsy, nonsyndromic intellectual disability, and movement disorders. STXBP1 mutations have recently been associated with mitochondrial pathology, although it remains unclear if this phenotype is a part of the core feature for this gene disorder. We report a 7-year-old boy who presented for diagnostic evaluation of intractable epilepsy, episodic ataxia, resting tremor, and speech regression following a period of apparently normal early development. Mild lactic acidemia was detected on one occasion at the time of an intercurrent illness. Due to the concern for mitochondrial disease, ophthalmologic evaluation was performed that revealed bilateral midperiphery pigmentary mottling. Optical coherence tomography (OCT testing demonstrated a bilaterally thickened ganglion cell layer in the perifovea. Skeletal muscle biopsy analysis showed no mitochondrial abnormalities or respiratory chain dysfunction. Exome sequencing identified a de novo c.1651C>T (p.R551C mutation in STXBP1. Although mitochondrial dysfunction has been reported in some individuals, our proband had only mild lactic acidemia and no skeletal muscle tissue evidence of mitochondrial disease pathology. Thus, mitochondrial dysfunction is not an obligate feature of STXBP1 disease.

Fetal pancreatic beta-cell function in pregnancies complicated by maternal diabetes mellitus: relationship to fetal acidemia and macrosomia.

Science.gov (United States)

Salvesen, D R; Brudenell, J M; Proudler, A J; Crook, D; Nicolaides, K H

1993-05-01

Our purpose was to investigate the relationship between fetal pancreatic beta-cell function and fetal acidemia and macrosomia in pregnancies complicated by maternal diabetes mellitus. A cross-sectional study at the Harris Birthright Research Centre for Fetal Medicine, London, was performed. In 32 pregnancies complicated by maternal diabetes mellitus cordocentesis was performed at 36 to 39 weeks' gestation for the measurement of umbilical venous blood pH, PO2, PCO2, lactate, and glucose concentration; plasma insulin immunoreactivity; and insulin/glucose ratio. A reference range for plasma insulin and insulin/glucose ratio was constructed by studying fetal blood samples from 80 women who did not have diabetes mellitus. Mean umbilical venous blood pH was significantly lower and plasma insulin immunoreactivity and insulin/glucose ratio were significantly higher than the appropriate normal mean for gestation. There were significant associations between (1) maternal and fetal blood glucose concentrations (r = 0.95, p < 0.0001), (2) fetal blood glucose and plasma insulin immunoreactivity (r = 0.57, p < 0.01), (3) fetal plasma insulin immunoreactivity and blood pH (r = -0.39, p < 0.05), and (4) fetal insulin/glucose ratio and degree of macrosomia (r = 0.76, p < 0.0001). Fetal pancreatic beta-cell hyperplasia is implicated in the pathogenesis of both fetal acidemia and macrosomia.

Metabolic evidence of vitamin B-12 deficiency, including high homocysteine and methylmalonic acid and low holotranscobalamin, is more pronounced in older adults with elevated plasma folate

Science.gov (United States)

Background: An analysis of data from the National Health and Nutrition Examination Survey indicated that in older adults exposed to folic acid fortification, the combination of low serum vitamin B-12 and elevated folate is associated with higher concentrations of homocysteine and methylmalonic acid ...

mma: An R Package for Mediation Analysis with Multiple Mediators

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Qingzhao Yu

2017-04-01

Full Text Available Mediation refers to the effect transmitted by mediators that intervene in the relationship between an exposure and a response variable. Mediation analysis has been broadly studied in many fields. However, it remains a challenge for researchers to consider complicated associations among variables and to differentiate individual effects from multiple mediators. [1] proposed general definitions of mediation effects that were adaptable to all different types of response (categorical or continuous, exposure, or mediation variables. With these definitions, multiple mediators of different types can be considered simultaneously, and the indirect effects carried by individual mediators can be separated from the total effect. Moreover, the derived mediation analysis can be performed with general predictive models. That is, the relationships among variables can be modeled using not only generalized linear models but also nonparametric models such as the Multiple Additive Regression Trees. Therefore, more complicated variable transformations and interactions can be considered in analyzing the mediation effects. The proposed method is realized by the R package 'mma'. We illustrate in this paper the proposed method and how to use 'mma' to estimate mediation effects and make inferences.

The effect of citrulline and arginine supplementation on lactic acidemia in MELAS syndrome☆

Science.gov (United States)

El-Hattab, Ayman W.; Emrick, Lisa T.; Williamson, Kaitlin C.; Craigen, William J.; Scaglia, Fernando

2013-01-01

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disorder in which nitric oxide (NO) deficiency may play a role in the pathogenesis of several complications including stroke-like episodes and lactic acidosis. Supplementing the NO precursors arginine and citrulline restores NO production in MELAS syndrome. In this study we evaluated the effect of arginine or citrulline on lactic acidemia in adults with MELAS syndrome. Plasma lactate decreased significantly after citrulline supplementation, whereas the effect of arginine supplementation did not reach statistical significance. These results support the potential therapeutic utility of arginine and citrulline in MELAS syndrome and suggest that citrulline supplementation may be more efficacious. However, therapeutic efficacy of these compounds should be further evaluated in clinical trials. PMID:25411654

The effect of citrulline and arginine supplementation on lactic acidemia in MELAS syndrome.

Science.gov (United States)

El-Hattab, Ayman W; Emrick, Lisa T; Williamson, Kaitlin C; Craigen, William J; Scaglia, Fernando

2013-12-01

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disorder in which nitric oxide (NO) deficiency may play a role in the pathogenesis of several complications including stroke-like episodes and lactic acidosis. Supplementing the NO precursors arginine and citrulline restores NO production in MELAS syndrome. In this study we evaluated the effect of arginine or citrulline on lactic acidemia in adults with MELAS syndrome. Plasma lactate decreased significantly after citrulline supplementation, whereas the effect of arginine supplementation did not reach statistical significance. These results support the potential therapeutic utility of arginine and citrulline in MELAS syndrome and suggest that citrulline supplementation may be more efficacious. However, therapeutic efficacy of these compounds should be further evaluated in clinical trials.

Hydrophobic modification of wood via surface-initiated ARGET ATRP of MMA

Energy Technology Data Exchange (ETDEWEB)

Fu Yanchun; Li Gang [Material Science and Engineering College, Northeast Forestry University, Harbin 150040 (China); Yu Haipeng, E-mail: yuhaipeng20000@yahoo.com.cn [Key laboratory of Bio-based Material Science and Technology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Material Science and Engineering College, Northeast Forestry University, Harbin 150040 (China); Liu Yixing, E-mail: yxl200488@sina.com [Key laboratory of Bio-based Material Science and Technology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Material Science and Engineering College, Northeast Forestry University, Harbin 150040 (China)

2012-01-15

To convert the hydrophilic surface of wood into a hydrophobic surface, the present study investigated activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) as a method of grafting methyl methacrylate (MMA) onto the wood surface. The wood treated with 2-bromoisobutyryl bromide and with the subsequently attached MMA via ARGET ATRP under different polymerization times (2 h, 4 h, 6 h, 8 h) were examined using scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. All the analyses confirmed that PMMA had been grafted onto the wood surface. Water contact angle measurement proved that the covering layer of PMMA on wood made the surface hydrophobic. Polymerization time had a positive influence on the contact angle value and higher contact angle can be produced with the prolongation of the polymerization time. When the reaction time was extended to 8 h, the contact angle of treated wood surface reached 130 Degree-Sign in the beginning, and remained at 116 Degree-Sign after 60 s. The ARGET ATRP method may raise an alteration on the wood surface modification.

Improvement in ionic conductivity of self-supported P(MMA-AN-VAc) gel electrolyte by fumed silica for lithium ion batteries

International Nuclear Information System (INIS)

Liao Youhao; Rao Mumin; Li Weishan; Tan Chunlin; Yi Jin; Chen Lang

2009-01-01

Fumed silica was used as a dopant in the preparation of poly(methyl methacrylate-acrylonitrile-vinyl acetate) (P(MMA-AN-VAc)) to improve the ionic conductivity of the P(MMA-AN-VAc)-based gel polymer electrolyte (GPE). The performance of the P(MMA-AN-VAc) membrane and its GPE for lithium ion battery use were studied by XRD, SEM, TGA, LSV, CA, EIS, and charge/discharge test. It is found that the doping of fumed silica in the P(MMA-AN-VAc) changes the membrane from semi-crystal to amorphous state and the pore structure of the membrane. By the doping of 10 wt.% fumed silica in the membrane, the porosity of the membrane increases with the pore dispersed more uniformly and interconnected and having higher electrolyte uptake, resulting in the improvement in ionic conductivity of the GPE from 3.48 x 10 -3 to 5.13 x 10 -3 S cm -1 at ambient temperature. On the other hand, the thermal stability of the membrane, the electrochemical stability of the GPE, and the cyclic performance of the battery are also improved.

The implementation of neonatal peritoneal dialysis in a clinical setting.

Science.gov (United States)

Unal, Sevim; Bilgin, Leyla; Gunduz, Mehmet; Uncu, Nermin; Azili, Mujdem Nur; Tiryaki, Tugrul

2012-10-01

To investigate etiology, outcome and complications related to neonatal peritoneal dialysis (PD). Neonates treated with PD in our neonatal intensive care unit during 2007-2010 were analyzed retrospectively. Among 4036 hospitalized neonates; 20 neonates (0.5%) who underwent 21 cycles of PD [7 preterm, 13 term; 13 female, 7 male] were included. The mean birth weight was 2930.2 ± 720.6 g (1120-4570), mean gestational age was 37.5 ± 3.5 weeks (27-41). The etiologic disorders included inborn errors of metabolism (propionic acidemia, methylmalonic acidemia, citrullinemia, glutaric aciduria type 2, maple syrup urine disease, 10), or acute renal failure secondary to perinatal asphyxia (4), sepsis (2), prematurity (2), hypoplastic left heart syndrome (1), kernicterus (1). The complications included peritonitis (2), early leakage (4), hemorrhage (1), catheter removal (3) and occlusion (2). The mortality rate was 50%. The gestational ages and birth weights of surviving neonates were higher (p neonates, chronic renal failure (1), severe (4) and moderate neuromotor impairment (2) developed within 4-43 months. PD, although invasive, is an effective therapy in neonates. The complexity and invasiveness of the procedure is probably responsible for high rate of complications and mortality. If appropriate catheter selection and technique in the placement should be done, PD might improve outcome.

O ESTRESSE NO MMA: AS ESTRATÉGIAS DE ENFRENTAMENTO PODEM MELHORAR O DESEMPENHO DOS LUTADORES?

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Isabella Belem

Full Text Available RESUMO Introdução: Um dos maiores fenômenos esportivos na atualidade, o Ultimate Fighting Championship (UFC, realizado no Brasil em 2013, movimentou entre R$ 15 e R$ 50 milhões, destacando-se na mídia internacional. Apesar dessa superprodução dos eventos, os estudos com atletas de MMA (Mixed Martial Arts ainda são escassos, sobretudo no que se refere aos aspectos psicológicos. Objetivo: Analisar estratégias de coping, níveis de estresse e características de treinamento de atletas paranaenses de MMA. Métodos: Foram estudados 50 atletas de MMA do sexo masculino, com idade de 25,0 ± 4,8 anos. Como instrumentos foram utilizados uma ficha de identificação, o Inventário Atlético de Estratégias de Coping e o Questionário de Estresse e Recuperação para Atletas (RESTQ-76 Sport. Na análise dos dados, utilizou-se estatística descritiva, teste de Shapiro-Wilk, teste "U" de Mann-Whitnney; teste de Kruskal-Wallis e coeficiente de correlação de Spearman; a significância adotada foi p < 0,05. Resultados: Os atletas com principal fonte de renda no MMA apresentaram maior "estresse geral" (p = 0,023 e "estresse social" (p = 0,043 . Conclusão: Conclui-se que quando o esporte é a principal fonte de renda dos atletas, o estresse dos lutadores é elevado. Quanto maior o volume de treino, mais o atleta busca estabelecer objetivos e maior é sua a capacidade de confrontar as adversidades. Além disso, a variedade de estratégias de coping utilizadas pelos lutadores melhora seu estado de recuperação (capacidades físicas e psicológicas durante as competições.

Interleukin-8 (IL-8) over-production and autocrine cell activation are key factors in monomethylarsonous acid [MMA(III)]-induced malignant transformation of urothelial cells

International Nuclear Information System (INIS)

Escudero-Lourdes, C.; Wu, T.; Camarillo, J.M.; Gandolfi, A.J.

2012-01-01

The association between chronic human exposure to arsenicals and bladder cancer development is well recognized; however, the underlying molecular mechanisms have not been fully determined. We propose that inflammatory responses can play a pathogenic role in arsenic-related bladder carcinogenesis. In previous studies, it was demonstrated that chronic exposure to 50 nM monomethylarsenous acid [MMA(III)] leads to malignant transformation of an immortalized model of urothelial cells (UROtsa), with only 3 mo of exposure necessary to trigger the transformation-related changes. In the three-month window of exposure, the cells over-expressed pro-inflammatory cytokines (IL-1β, IL-6 and IL-8), consistent with the sustained activation of NFKβ and AP1/c-jun, ERK2, and STAT3. IL-8 was over-expressed within hours after exposure to MMA(III), and sustained over-expression was observed during chronic exposure. In this study, we profiled IL-8 expression in UROtsa cells exposed to 50 nM MMA(III) for 1 to 5 mo. IL-8 expression was increased mainly in cells after 3 mo MMA(III) exposure, and its production was also found increased in tumors derived from these cells after heterotransplantation in SCID mice. UROtsa cells do express both receptors, CXCR1 and CXCR2, suggesting that autocrine cell activation could be important in cell transformation. Supporting this observation and consistent with IL-8 over-expression, CXCR1 internalization was significantly increased after three months of exposure to MMA(III). The expression of MMP-9, cyclin D1, bcl-2, and VGEF was significantly increased in cells exposed to MMA(III) for 3 mo, but these mitogen-activated kinases were significantly decreased after IL-8 gene silencing, together with a decrease in cell proliferation rate and in anchorage-independent colony formation. These results suggest a relevant role of IL-8 in MMA(III)-induced UROtsa cell transformation. -- Highlights: ► IL-8 is over-expressed in human MMA(III)-exposed urothelial

Predictive value of late decelerations for fetal acidemia in unselective low-risk pregnancies.

Science.gov (United States)

Sameshima, Hiroshi; Ikenoue, Tsuyomu

2005-01-01

We evaluated the clinical significance of late decelerations (LD) of intrapartum fetal heart rate (FHR) monitoring to detect low pH (LD (occasional, 50%; recurrent, > or = 50%) and severity (reduced baseline FHR accelerations and variability) of LD, and low pH (test, and one-way analysis of variance with the Bonferroni/Dunn test. In the 5522 low-risk pregnancies, 301 showed occasional LD and 99 showed recurrent LD. Blood gases and pH values deteriorated as the incidence of LD increased and as baseline accelerations or variability was decreased. Positive predictive value for low pH (LD, and > 50% in recurrent LD with no baseline FHR accelerations and reduced variability. In low-risk pregnancies, information on LD combined with acceleration and baseline variability enables us to predict the potential incidence of fetal acidemia.

Synthesis of α-Bromine- Terminated Polystyrene Macroinitiator and Its Initiation of MMA Polymerization by ATRP

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

In the present paper the synthesis of block copolymers via the transformation from living anionic polymerization (LAP) to atom transfer radical polymerization (ATRP) was described. Α-Bromine-terminated polystyrenes(PStBr) in the LAP step was prepared by using n-BuLi as initiator, tetrahydrofuran (THF) as the activator, α-methylstyrene (α-MeSt) as the capping group and liquid bromine (Br2) as the bromating agent. The effects of reaction conditions such as the amounts of α-MeSt, THF, and Br2 as well as molecular weight of polystyrene on the bromating efficiency (BE) and coupling extent (CE) were examined. The present results show that the yield of PStBr obtained was more than 93.8% and the coupling reaction was substantially absent. PStBr was further used as the macroinitiator in the polymerization of methyl-methacrylate(MMA) in the presence of copper(Ⅰ) halogen and 2,2-bipyridine(bpy) complexes. It was found that the molecular weight of the resulted PSt-b-PMMA increased linearly with the increase of the conversion of MMA and the polydispersity was 1.2-1.6. The structures of PStBr and P(St-b-MMA) were characterized by 1H NMR spectra.

Flexible Polymeric Materials Prepared by Radiation Copolymerization of MMA/ Pyridene in the Presence of Acrylic Acid

International Nuclear Information System (INIS)

Hegazy, D.E.

2014-01-01

Gamma-irradiation initiated copolymerization of methyl methacrylate (MMA) and pyridine (Py) was carried out at room temperature.To improve the obtained copolymer functionality and molecular weight, acrylic acid (AA) was incorporated into the mixture during irradiation. The samples were characterized by thermal analysis techniques (DSC and TGA), Fourier transform infrared spectroscopy (FTIR) and UV-VIS spectrometry. Molecular weight of the obtained copolymers was determined using gel permeation chromatography (GPC). The variation of refractive index and surface hardness with the molecular weight were also investigated. The results obtained show a decrease in glass transition temperature and the hardness (shore D) of the supporting matrix for P(MMA/Py) copolymers with a pronounced increase of the molecular weight. The addition of PAA into the matrix enhanced the hardness and shifts the glass transition temperature to a little higher temperature with a pronounced decrease in the melting temperature. The obtained materials maintain good structural order and flexibility resulting from the softening effect of pyridine onto MMA matrix. The studies performed made possible the selection of experimental conditions to be adequate for the production of new co polymeric materials with high molecular weight that having good flexibility and transparent properties.

MMA-EoS: A Computational Framework for Mineralogical Thermodynamics

Science.gov (United States)

Chust, T. C.; Steinle-Neumann, G.; Dolejš, D.; Schuberth, B. S. A.; Bunge, H.-P.

2017-12-01

We present a newly developed software framework, MMA-EoS, that evaluates phase equilibria and thermodynamic properties of multicomponent systems by Gibbs energy minimization, with application to mantle petrology. The code is versatile in terms of the equation-of-state and mixing properties and allows for the computation of properties of single phases, solution phases, and multiphase aggregates. Currently, the open program distribution contains equation-of-state formulations widely used, that is, Caloric-Murnaghan, Caloric-Modified-Tait, and Birch-Murnaghan-Mie-Grüneisen-Debye models, with published databases included. Through its modular design and easily scripted database, MMA-EoS can readily be extended with new formulations of equations-of-state and changes or extensions to thermodynamic data sets. We demonstrate the application of the program by reproducing and comparing physical properties of mantle phases and assemblages with previously published work and experimental data, successively increasing complexity, up to computing phase equilibria of six-component compositions. Chemically complex systems allow us to trace the budget of minor chemical components in order to explore whether they lead to the formation of new phases or extend stability fields of existing ones. Self-consistently computed thermophysical properties for a homogeneous mantle and a mechanical mixture of slab lithologies show no discernible differences that require a heterogeneous mantle structure as has been suggested previously. Such examples illustrate how thermodynamics of mantle mineralogy can advance the study of Earth's interior.

The permeability of EUDRAGIT RL and HEMA-MMA microcapsules to glucose and inulin.

Science.gov (United States)

Douglas, J A; Sefton, M V

1990-10-05

Measurement of the rate of glucose diffusion from EUDGRAGIT RL and HEMA-MMA microcapsules coupled with a Thiele modulus/Biot number analysis of the glucose utilization rate suggests that pancreatic islets and CHO (Chinese hamster ovary) cells (at moderate to high cell densities) should not be adversely affected by the diffusion restrictions associated with these capsule membranes. The mass transfer coefficients for glucose at 20 degrees C were of the same order of magnitude for both capsules, based on release measurements: approximately 5 x 10(-6) cm/s for EUDRAGIT RL and approximately 2 x 10(-6) for HEMA-MMA. Inulin release from EUDRAGIT RL was slower than for glucose (mass transfer coefficient 14 +/- 4 x 10(-8) cm/s). The Thiele moduli were much less than 1, either for a single islet at the center of a capsule or CHO cells uniformly distributed throughout a capsule at 10(-6) cells/ mL, so that diffusion restrictions within the cells in EUDRAGIT RL or 800 microm HEMA-MMA capsules should be negligible. The ratio of external to internal diffusion resistance (Biot number) was less than 1, so that at most, only a small diffusion effect on glucose utilization should be expected (i.e., the overall effectiveness factors were greater than 0.8). These calculations were consistent with experimental observation of encapsulated islet behavior but not fully with CHO cell behavior. Permeability restricted cell viability and growth is potentially a major limitation of encapsulated cells; further analysis is warranted.

Effect of PVA-co-MMA Copolymer on the Physical, Mechanical, and Thermal Properties of Tropical Wood Materials

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Md. Saiful Islam

2014-01-01

Full Text Available The present study demonstrates the effect of copolymer on the physical, mechanical, and thermal properties of tropical wood and wood polymer composites (WPCs. Mixed monomers of methyl methacrylate (MMA and polyvinyl alcohol (PVA were effectively impregnated into the cellular structure of several types of tropical wood, which then underwent a catalyst-thermal process to polymerize and form WPC. The manufacturing of WPC was confirmed through Fourier transform infrared (FTIR spectroscopy and scanning electron microscopic (SEM analysis. The SEM observation showed that polymer converted from monomers filled up wood cell cavities and tightly interacted with wood matrix. The X-ray diffraction results reveal that the degree of crystallinity was significantly improved upon impregnation with PVA-co-MMA copolymer. The modulus of elasticity (MOE and compressive modulus were found to be significantly higher after treatment with MMA/PVA indicating improvement of mechanical properties of the wood samples. In addition, the modified WPC had lower water absorption compared to their corresponding raw samples. It is interesting to note that thermogravimetric (TGA analysis shows an extensive improvement in thermal properties of WPC.

Glutaric acidemia type II: gene structure and mutations of the electron transfer flavoprotein:ubiquinone oxidoreductase (ETF:QO) gene.

Science.gov (United States)

Goodman, Stephen I; Binard, Robert J; Woontner, Michael R; Frerman, Frank E

2002-01-01

Glutaric acidemia type II is a human inborn error of metabolism which can be due to defects in either subunit of electron transfer flavoprotein (ETF) or in ETF:ubiquinone oxidoreductase (ETF:QO), but few disease-causing mutations have been described. The ETF:QO gene is located on 4q33, and contains 13 exons. Primers to amplify these exons are presented, together with mutations identified by molecular analysis of 20 ETF:QO-deficient patients. Twenty-one different disease-causing mutations were identified on 36 of the 40 chromosomes.

Synthesis of Fluorinated Amphiphilic Block Copolymers Based on PEGMA, HEMA, and MMA via ATRP and CuAAC Click Chemistry

OpenAIRE

Erol, Fatime Eren; Sinirlioglu, Deniz; Cosgun, Sedat; Muftuoglu, Ali Ekrem

2014-01-01

Synthesis of fluorinated amphiphilic block copolymers via atom transfer radical polymerization (ATRP) and Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition (CuAAC) was demonstrated. First, a PEGMA and MMA based block copolymer carrying multiple side-chain acetylene moieties on the hydrophobic segment for postfunctionalization was carried out. This involves the synthesis of a series of P(HEMA-co-MMA) random copolymers to be employed as macroinitiators in the controlled synthesis of P(HEMA-co-M...

Formation of hyperbranched polymers in atom transfer radical copolymerization of MMA and DVB

Institute of Scientific and Technical Information of China (English)

无

2010-01-01

Hyperbranched poly(methyl methacrylate)s (HPMMAs) have been successfully prepared by atom transfer radical copolymerization of MMA and divinylbenzene (DVB).Kinetic study shows complete consumption of the initiator in 0.5 h,and relatively low polymerization rate when DVB content in the feed was high.By analyzing MALDI-TOF spectra of the resulting copolymers,the linear A n B (n=0,1,2,3) oligomers were formed in 0.5 h of polymerization,and then the oligomers reacted each other to form dimers,further reactions produced HPMMA.The SEC and NMR spectroscopies were used to trace the polymerization,and the results demonstrate that small amount of the branching reactions occur in the initial polymerization,and the branched polymers are significantly generated past a certain conversion depending upon the feed ratios.Raising the content of DVB in the monomer mixture can increase the pendent vinyl groups of the linear oligo-inimers,leading to gelation at low MMA conversion.

Influence of Reactive Emulsifiers on Emulsion Polymerization of MMA/BA%反应性乳化剂对MMA/BA乳液聚合的影响

Institute of Scientific and Technical Information of China (English)

郭林晖; 马承银

2004-01-01

将不同性质的反应性乳化剂应用于MMA/BA乳液聚合,对聚合过程的特性、乳胶粒子的大小和形态及乳液的性能进行了研究,发现不同性质的反应性乳化剂对无皂乳液聚合有不同的影响.

Clinical experience with N-carbamylglutamate in a single-centre cohort of patients with propionic and methylmalonic aciduria

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Alberto Burlina

2016-09-01

Conclusion: These observations suggest that, in addition to short-term benefits for the acute treatment of hyperammonaemia, NCG may be effective and well tolerated as a long-term treatment in patients with severe PA and MMA, and that further prospective studies are warranted.

Polymerization of MMA catalyzed by different novel mixed ligand lanthanocene ｛ ( Cp ) ( Cl ) LnSchiff-base (THF) ｝, ( COT ) Ln(methoxyethylindenyl) (THF)/Al (i-Bu) 3 systems

Institute of Scientific and Technical Information of China (English)

YOUSAF, Muhammad; QIAN, Yan-Long; FENG, Zuo-Feng; HUANG, Ji-Ling; SUN, Jun-Quan; PAN, Zhi-Da

2000-01-01

This article deals that the rare earth metal complexes along with Al (i-Bu)3 can catalyze the polymerization of methyl methacrylate (MMA) into high molecular weight poly(MMA) along with narrow molecular weight distributions (MWD). A typical example wan mentioned in the case of ｛Cp(Cl)Sm Schiff-base(THF)｝ which expresses maximum (conv.%= 55.46 and Mn=354×103) efficiency along with narrow MWD(Mw/Mn＜2) at 60°C. The resulting polymer was partially syndiotactic (＞60%). The effect of the catalyst, temperature, catalyst/MMA molar ratio, catalyst/Al(i-Bu)3 molar ratio on the polymerization of MMA at 60°C were also investigated.

The Effect of the Chain Length on MMA Free Radicl Polymerization

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

In the polymerization process of methyl methacrylate (MMA), the Arrhenius parameters (activation energy and frequency factor) of propagating reaction monotonically decrease with increasing monomer conversion. At the beginning and middle stage of the propagating reaction, the increase of radical chain length is the main reason of above mentioned change. And at the end stage, the sharp decrease of kp indicates that the activation energy is approximately incline to zero and the propagating reaction is controlled by molecular diffusion motion.

Subtilomycin: A New Lantibiotic from Bacillus subtilis Strain MMA7 Isolated from the Marine Sponge Haliclona simulans

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Teresa M. Barbosa

2013-06-01

Full Text Available Bacteriocins are attracting increased attention as an alternative to classic antibiotics in the fight against infectious disease and multidrug resistant pathogens. Bacillus subtilis strain MMA7 isolated from the marine sponge Haliclona simulans displays a broad spectrum antimicrobial activity, which includes Gram-positive and Gram-negative pathogens, as well as several pathogenic Candida species. This activity is in part associated with a newly identified lantibiotic, herein named as subtilomycin. The proposed biosynthetic cluster is composed of six genes, including protein-coding genes for LanB-like dehydratase and LanC-like cyclase modification enzymes, characteristic of the class I lantibiotics. The subtilomycin biosynthetic cluster in B. subtilis strain MMA7 is found in place of the sporulation killing factor (skf operon, reported in many B. subtilis isolates and involved in a bacterial cannibalistic behaviour intended to delay sporulation. The presence of the subtilomycin biosynthetic cluster appears to be widespread amongst B. subtilis strains isolated from different shallow and deep water marine sponges. Subtilomycin possesses several desirable industrial and pharmaceutical physicochemical properties, including activity over a wide pH range, thermal resistance and water solubility. Additionally, the production of the lantibiotic subtilomycin could be a desirable property should B. subtilis strain MMA7 be employed as a probiotic in aquaculture applications.

Subtilomycin: A New Lantibiotic from Bacillus subtilis Strain MMA7 Isolated from the Marine Sponge Haliclona simulans

Science.gov (United States)

Phelan, Robert W.; Barret, Matthieu; Cotter, Paul D.; O’Connor, Paula M.; Chen, Rui; Morrissey, John P.; Dobson, Alan D. W.; O’Gara, Fergal; Barbosa, Teresa M.

2013-01-01

Bacteriocins are attracting increased attention as an alternative to classic antibiotics in the fight against infectious disease and multidrug resistant pathogens. Bacillus subtilis strain MMA7 isolated from the marine sponge Haliclona simulans displays a broad spectrum antimicrobial activity, which includes Gram-positive and Gram-negative pathogens, as well as several pathogenic Candida species. This activity is in part associated with a newly identified lantibiotic, herein named as subtilomycin. The proposed biosynthetic cluster is composed of six genes, including protein-coding genes for LanB-like dehydratase and LanC-like cyclase modification enzymes, characteristic of the class I lantibiotics. The subtilomycin biosynthetic cluster in B. subtilis strain MMA7 is found in place of the sporulation killing factor (skf) operon, reported in many B. subtilis isolates and involved in a bacterial cannibalistic behaviour intended to delay sporulation. The presence of the subtilomycin biosynthetic cluster appears to be widespread amongst B. subtilis strains isolated from different shallow and deep water marine sponges. Subtilomycin possesses several desirable industrial and pharmaceutical physicochemical properties, including activity over a wide pH range, thermal resistance and water solubility. Additionally, the production of the lantibiotic subtilomycin could be a desirable property should B. subtilis strain MMA7 be employed as a probiotic in aquaculture applications. PMID:23736764

Atom-transfer radical polymerization of methyl methacrylate (MMA) using CuSCN as the catalyst

NARCIS (Netherlands)

Singha, N.K.; Klumperman, B.

2000-01-01

The effect of CuSCN as a catalyst in atom-transfer radical polymerization (ATRP) was investigated. CuSCN can successfully be used for the ATRP of MMA. Substituted bipyridines as well as imines can be used to stabilize the copper complex in solution. CuSCN induces faster polymerization compared to

Growth and characterization of MMA/SiO2 hybrid low-k thin films for ...

Indian Academy of Sciences (India)

We have successfully incorporated MMA monomer and eliminated the polymerization step to lower the dielectric constant of deposited thin film. The presence of peak of C=C bond in Fourier transform infrared (FTIR) spectra and carbon peak in energy dispersive (EDAX) spectra confirms the incorporation of carbon in the film ...

Modification of phase transitions in swift heavy ion irradiated and MMA-grafted ferroelectric fluoro-polymers

International Nuclear Information System (INIS)

Petersohn, E.; Betz, N.; Le Moel, A.

1994-01-01

Ferroelectric polyvinylidene fluoride (β) and copolymers of vinylidene fluoride trifluoroethylene (P(VDF/TrFE)) films were irradiated with swift heavy ions and post irradiation grafted with methyl methacrylate (MMA). We have studied the influence of irradiation parameters such as the ion fluence, the type of ion and the electronic stopping power, on the melting and crystallization temperatures and the ferroelectric-paraelectric phase transitions, by differential scanning calorimetry (DSC) and dielectric measurements. The relation between the shift in the transition temperatures and the ion fluence is described by a single term equation. Ion track grafting with MMA affects the ferroelectric-paraelectric phase transitions in P(VDF/TrFE) and leads to a strong amorphization of the polymer films. The grafting in β PVDF occurs mainly on the surface of the samples and no change in the transition temperatures is observed. (authors). 12 refs., 6 figs., 2 tabs

Synthesis and optimization of EA-MMA copolymer emulsion%EA-MMA共聚乳液合成工艺及优化

Institute of Scientific and Technical Information of China (English)

张成芬; 武玉民

2011-01-01

以丙烯酸乙酯(EA)和甲基丙烯酸甲酯(MMA)为共聚单体、过硫酸钾(KPS)为引发剂、十二烷基硫酸钠(SDS)和壬基酚聚氧乙烯醚(OP-10)为复合乳化剂,采用乳液聚合法合成出一种稳定的EA-MMA乳液.通过单因素试验法考察了乳化剂浓度、引发剂浓度、反应温度和反应时间等因素对乳液平均粒径和单体转化率的影响,并采用正交试验法进一步优选出制备EA-MMA乳液的最佳工艺条件.结果表明:当w(乳化剂)=2.0%、w(引发剂)=0.60%、反应时间为4 h和反应温度为80℃时,制成的EA-MMA乳液较稳定,并且单体转化率相对最高.%With ethyl acrylate(EA) and methyl methacrylate( MMA) as comonomers ,potassium persulfate(KPS)as initiator,and sodium dodecyl sulfate(SDS) and nonylphenol ethoxylates(OP-10) as composite emulsifier,a stable EA-MMA emulsion was synthesized by emulsion polymerization. The influences of some factor(such as emulsifier concentration,initiator concentration,reaction temperature and reaction time) on average particle size of emulsion and monomer conversion rate were investigated by single factor experiment method,then the optimal process conditions of preparing EA-MMA emulsion were preferred by orthogonal experiment method. The results showed that the EA-MMA emulsion had better stability and relatively highest monomer conversion rate when the mass fractions of emulsifier and initiator were 2.0％ and 0.60％ respectively,the reaction time and reaction temperature were 4 h and 80 ℃ respectively.

Grimsel test site. Investigation phase VI. Pore space geometry project. Characterisation of pore space geometry by 14C-MMA impregnation

International Nuclear Information System (INIS)

Kelokaski, M.; Siitari-Kauppi, M.; Kauppi, I.; Hellmuth, K.-H.; Moeri, A.; Inderbitzin, L.; Biggin, C.; Kickmaier, W.; Martin, A.

2010-04-01

In Finland high-level radioactive waste is planned to be disposed of in a deep geological repository within a crystalline host rock. The potential role of the geosphere as a safety barrier in repository performance assessment is well established. However, uncertainties in both transport pathway definition and pore space characterisation of crystalline rock still exist and the repository safety evaluation today requires going from laboratory and surface-based field work to the underground repository level. Little is known about the changes to rock transport properties during sampling and decompression. Recent investigations using resin impregnation of the rock matrix at the Grimsel Test Site imply that non-conservative errors in calculated transport properties derived from laboratory data may reach factors of two to three. Due to the potentially great significance of pore space characterisation to safety analysis calculations, it was decided to study the rock matrix characteristics in situ using methylmethacrylate (MMA) resin labelled with 14 C. During the last decade, the poly-methylmethacrylate (PMMA) method has been developed for characterising the porosity of low permeable granitic rocks in the laboratory. Impregnation with 14 C-labelled methylmethacrylate ( 14 C-MMA) and autoradiography allows investigation of the spatial distribution of accessible porosity at the centimetre scale. Quantitative measurements of total or mineral-specific local porosities have been obtained using image analysis tools. Electron microscopy examinations and mercury porosimetry measurements have provided detailed information on pore and fissure apertures. The objective of this work was to develop an in situ application of the PMMA impregnation technique. The changes in rock porosity due to stress relaxation when overcoring the samples from the bedrock for the laboratory studies were examined. The concept behind the work was to inject 14 C-MMA from a central borehole at a depth of

Preparation and characterization of BADCy/MMA semi-IPN%BADCy/MMA半互穿网络的制备及性能表征

Institute of Scientific and Technical Information of China (English)

祝保林

2012-01-01

The cyanate ester resin/PMMA（BADCy/MMA-SIPN） with semi-interpenetrating polymers network were prepared by adding methyl methacrylate（MMA） monomer（synchronous synthisis）or MMA prepolymer（asynchronous synthesis）into the melting cyanate ester resin（BADCy） and caused.The bulk polymerization occurred.The effects of MMA contents on the mechanical properties and thermal performance of the BADCy/MMA-SIPN were investigated by the mechanical testing,infrared and DSC analysis.The results showed that the mechanical properties and heat resistance of the cyanate ester resin system were greatly improved by the formation of interpenetrating network.The impact strength,flexural strength and glass transition temperature were increased by 97.8%,58.6%,and 65 ℃,respectively.%在加热熔融的氰酸酯树脂（BADCy）中加入甲基丙烯酸甲酯（MMA）单体（同步合成法）或MMA预聚体（异步合成法）并引发使其发生本体聚合,制备了具有半互穿聚合物网络结构的氰酸酯树脂/聚甲基丙烯酸甲酯（BADCy/MMA-SIPN）,通过力学性能测试,红外及DSC分析研究了MMA含量对体系力学性能和热性能的影响。结果表明,互穿网絡的形成使氰酸酯树脂体系的力学性能和耐热性能都有较大的提高,冲击强度、弯曲强度及玻璃化温度分别提高了97.8%、58.6%和65℃。

ANÁLISE SOBRE OS MÉTODOS E ESTRATÉGIAS DE PERDA DE PESO EM ATLETAS DE MIXED MARTIAL ARTS (M.M.A. EM PERÍODO PRÉ-COMPETITIVO

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Jessica Maria Leite de Oliveira e Silva

2014-02-01

Full Text Available Mixed Martial Arts (M.M.A. is a sport that combines various types of fight modes in a single combat rule. It requires heavy training and attention to all details of the mixed martial arts in order for the athlete to be 100% fit and precise in the day of the fight. The aim of this study was to evaluate the methods and strategies used in M.M.A. for weigh loss in the athlete’s physiological system, as well as to evaluate their performance. A questionnaire was given to the M.M.A. athletes for them to answer what they practice in order to accomplish rapid body mass loss. The program, Microsoft Excel 2007, was utilized for tab graphics. A total of 8 male athletes, from the ages of 21 to 35, responded to the questionnaire. The method used for weight loss by using sauna and antiperspirant clothes was 90% and the restriction of carbohydrate was 80% and liquid was 40%, being that this restriction and weight loss occurs in the pre-competitive week. These strategies cause harmful effects to the M.M.A. athletes, such as hormonal imbalance, electrolyte imbalance, cardiovascular system alterations, decreased renal function, impaired mental status in the long term, as well as mood changes. An Inadequate diet and short recovery time can lower the athlete's anaerobic performance, which prevails in M.M.A. This research can teach M.M.A athletes that through gradual changes and some nutritional rules, they can obtain a solution to impede rapid weight loss.

Clinical and neurocognitive outcome in symptomatic isovaleric acidemia

Directory of Open Access Journals (Sweden)

Grünert Sarah C

2012-01-01

Full Text Available Abstract Background Despite its first description over 40 years ago, knowledge of the clinical course of isovaleric acidemia (IVA, a disorder predisposing to severe acidotic episodes during catabolic stress, is still anecdotal. We aimed to investigate the phenotypic presentation and factors determining the neurological and neurocognitive outcomes of patients diagnosed with IVA following clinical manifestation. Methods Retrospective data on 21 children and adults with symptomatic IVA diagnosed from 1976 to 1999 were analyzed for outcome determinants including age at diagnosis and number of catabolic episodes. Sixteen of 21 patients were evaluated cross-sectionally focusing on the neurological and neurocognitive status. Additionally, 155 cases of patients with IVA published in the international literature were reviewed and analyzed for outcome parameters including mortality. Results 57% of study patients (12/21 were diagnosed within the first weeks of life and 43% (9/21 in childhood. An acute metabolic attack was the main cause of diagnostic work-up. 44% of investigated study patients (7/16 showed mild motor dysfunction and only 19% (3/16 had cognitive deficits. No other organ complications were found. The patients' intelligence quotient was not related to the number of catabolic episodes but was inversely related to age at diagnosis. In published cases, mortality was high (33% if associated with neonatal diagnosis, following manifestation at an average age of 7 days. Conclusions Within the group of "classical" organic acidurias, IVA appears to be exceptional considering its milder neuropathologic implications. The potential to avoid neonatal mortality and to improve neurologic and cognitive outcome under early treatment reinforces IVA to be qualified for newborn screening.

十八烷/聚(St-MMA)相变微胶囊制备及表征%Preparation and Characterization of n-Octadecane/P(St-MMA) Phase-change Microcapsules

Institute of Scientific and Technical Information of China (English)

武卫莉; 李江坤

2017-01-01

采用乳液聚合的方法,分别选取聚苯乙烯(PS)、聚甲基丙烯酸甲酯(PMMA)或苯乙烯和甲基丙烯酸甲酯的共聚物为壁材,正十八烷为芯材,十二烷基苯磺酸钠(SDBS)为乳化剂,制作相变储能微胶囊.用粒径分析仪、透射电子显微镜(TEM)、热重分析仪(TG)和示差扫描量热测试仪(DSC)对微胶囊的形貌、相变热性能和热稳定性分别进行表征.结果表明:壁材选取两者共聚物,当两种单体的比例为St∶ MMA=1∶5,SDBS用量为1.5g(总质量的3％)时,微胶囊粒径大小均匀,粒子分散性好,壁材的包裹性好.微胶囊的放热峰为起始温度为27.3℃,终止温度为31.9℃,相变温度为28.9℃,相变焓为48.4J/g.TG表明长期使用温度不能超过131℃.IR分析微胶囊中含有芯材和壁材.这种十八烷/聚(St-MMA)相变微胶囊可以用于诸能材料.%A phase-change stored energy microcapsules were prepared by polymerization,in which polystyrene (PS),poly methyl methacrylate (PMMA) or copolymers of styrene and methyl methacrylate were used as shell materials,n-octadecane was used as a core material,and sodium dodecyl benzene sulfonate (SDBS) as a emulsifier.The morphology,phase-change thermal properties and thermal stability of microcapsules,respectively,were characterized by particle size analyzer,transmission electron microscope (TEM),thermogravimetric analyzer (TG) and differential scanning calorimetry (DSC).The results show that the particle size of microcapsules is uniform,the particle dispersion is good,and the shell is well wrapped when the copolymer of styrene (St) and methyl methacrylate (MMA),both mass ratio is 1∶5),is used as shell material,and sodium dodecyl benzene sulfonate content is 1.5g (3％ of the total mass).The heat release peaks of microcapsules are at 27.3℃ of starting temperature,at 31.9℃ of end temperature,and the phase transformation temperature is 28.9℃,the phase-change enthalpy of microcapsules is 48.4J

Ophthalmic manifestations of methylmalonic aciduria accompanied with homocystinuria

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Qiu-Jing Huang

2015-12-01

Full Text Available Methylmalonicaciduia(MMAaccompanied with homocystinuria is a rare autosomal-recessive with congenital metabolic disorder of Vitamin B12. There are three subtypes, cblC, cblD, cblF, in which cblC is the most common one. The diagnostic tests are tandem mass spectrometry and gas chromatography-mass spectrometry. Tests for activity of enzyme in fibroblasts from skin, complementary assay and genetic analysis can be used to make the subtype clear. Early-onset patients, defined by onset of symptoms before the age of 1 year, may have severe ocular involvement, including visual loss, nystagmus, strabismus, retinopathy, maculopathy, optic atrophy, abnormal electroretinography. Late-onset patients, defined by onset of symptoms after the age of 4 year, rarely have ocular manifestations. The pathogenesis of the ophthalmic symptoms may be related to the high level of homocystine, oxidative stress and the abnormal development of nervous systems. The treatment for MMA accompanied with homocystinuria is mostly symptomatic based. Ophthalmic treatment is limited. Early supplement of methionine,GSH or other antioxidants may be helpful for retinopathy. There is no standard ophthalmological examination for those patients in China. It is critical to set up inter-departmental cooperation and early stage examination for the treatments and outcomes of the patients.

Central Venous Catheter-Related Bloodstream Infection with Kocuria kristinae in a Patient with Propionic Acidemia.

Science.gov (United States)

Kimura, Masato; Kawai, Eichiro; Yaoita, Hisao; Ichinoi, Natsuko; Sakamoto, Osamu; Kure, Shigeo

2017-01-01

Kocuria kristinae is a catalase-positive, coagulase-negative, Gram-positive coccus found in the environment and in normal skin and mucosa in humans; however, it is rarely isolated from clinical specimens and is considered a nonpathogenic bacterium. We describe a case of catheter-related bacteremia due to K. kristinae in a young adult with propionic acidemia undergoing periodic hemodialysis. The patient had a central venous catheter implanted for total parenteral nutrition approximately 6 months prior to the onset of symptoms because of repeated acute pancreatitis. K. kristinae was isolated from two sets of blood cultures collected from the catheter. Vancomycin followed by cefazolin for 16 days and 5-day ethanol lock therapy successfully eradicated the K. kristinae bacteremia. Although human infections with this organism appear to be rare and are sometimes considered to result from contamination, physicians should not underestimate its significance when it is isolated in clinical specimens.

Effect of Inhibitors on Atom Transfer Radical Polymerization of MMA

Institute of Scientific and Technical Information of China (English)

张鸿; 徐冬梅; 张可达

2005-01-01

Effect of a series of inhibitors as additives on atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) with FeCl2/PPh3 as catalyst system was studied, including 2,4,6-trinitrophenol (TNP), 4-methoxyphenol (4-MP), hydroquinone (HQ) and nitrobenzene (NB). It was found that TNP was the only. efficient additive for ATRP among these inhibitors. In the presence of small amounts of TNP, the polymerization proceeded rapidly after induction period to yield the polymers with controlled molecular weights and narrow molecular weight distributions (MWD). The initiating efficiency of the modified catalyst system with TNP was increased. The mechanism was proposed and confirmed by the end group analysis of the polymer.

In vivo enzyme activity in inborn errors of metabolism

Energy Technology Data Exchange (ETDEWEB)

Thompson, G.N.; Walter, J.H.; Leonard, J.V.; Halliday, D. (Clinical Research Centre, Harrow (England))

1990-08-01

Low-dose continuous infusions of (2H5)phenylalanine, (1-13C)propionate, and (1-13C)leucine were used to quantitate phenylalanine hydroxylation in phenylketonuria (PKU, four subjects), propionate oxidation in methylmalonic acidaemia (MMA, four subjects), and propionic acidaemia (PA, four subjects) and leucine oxidation in maple syrup urine disease (MSUD, four subjects). In vivo enzyme activity in PKU, MMA, and PA subjects was similar to or in excess of that in adult controls (range of phenylalanine hydroxylation in PKU, 3.7 to 6.5 mumol/kg/h, control 3.2 to 7.9, n = 7; propionate oxidation in MMA, 15.2 to 64.8 mumol/kg/h, and in PA, 11.1 to 36.0, control 5.1 to 19.0, n = 5). By contrast, in vivo leucine oxidation was undetectable in three of the four MSUD subjects (less than 0.5 mumol/kg/h) and negligible in the remaining subject (2 mumol/kg/h, control 10.4 to 15.7, n = 6). These results suggest that significant substrate removal can be achieved in some inborn metabolic errors either through stimulation of residual enzyme activity in defective enzyme systems or by activation of alternate metabolic pathways. Both possibilities almost certainly depend on gross elevation of substrate concentrations. By contrast, only minimal in vivo oxidation of leucine appears possible in MSUD.

In vivo enzyme activity in inborn errors of metabolism

International Nuclear Information System (INIS)

Thompson, G.N.; Walter, J.H.; Leonard, J.V.; Halliday, D.

1990-01-01

Low-dose continuous infusions of [2H5]phenylalanine, [1-13C]propionate, and [1-13C]leucine were used to quantitate phenylalanine hydroxylation in phenylketonuria (PKU, four subjects), propionate oxidation in methylmalonic acidaemia (MMA, four subjects), and propionic acidaemia (PA, four subjects) and leucine oxidation in maple syrup urine disease (MSUD, four subjects). In vivo enzyme activity in PKU, MMA, and PA subjects was similar to or in excess of that in adult controls (range of phenylalanine hydroxylation in PKU, 3.7 to 6.5 mumol/kg/h, control 3.2 to 7.9, n = 7; propionate oxidation in MMA, 15.2 to 64.8 mumol/kg/h, and in PA, 11.1 to 36.0, control 5.1 to 19.0, n = 5). By contrast, in vivo leucine oxidation was undetectable in three of the four MSUD subjects (less than 0.5 mumol/kg/h) and negligible in the remaining subject (2 mumol/kg/h, control 10.4 to 15.7, n = 6). These results suggest that significant substrate removal can be achieved in some inborn metabolic errors either through stimulation of residual enzyme activity in defective enzyme systems or by activation of alternate metabolic pathways. Both possibilities almost certainly depend on gross elevation of substrate concentrations. By contrast, only minimal in vivo oxidation of leucine appears possible in MSUD

Acute effect of a fight of Mixed Martial Arts (MMA on the serum concentrations of testosterone, cortisol, creatine kinase, lactate, and glucose

Directory of Open Access Journals (Sweden)

Rodrigo Poderoso de Souza

2017-06-01

Full Text Available The aim of this study was to analyse the serum concentrations of testosterone (T, cortisol (C, lactate (LAC, creatine kinase (CK and glucose (GLU on mixed martial arts (MMA athletes, before and after a fight. We divided 20 MMA athletes into two groups of 10 fighters each, according to the result of a fight, and were then evaluated four times: 24 hours before (-24h, one hour before (-1h, immediately after (0h and 24 hours after the fight (+24h. It was observed: a significant decrease in T and T/C between moment -24h and 0h and a subsequent increase between the moment 0h and +24h and a reverse behaviour in variables C, LAC and GLU (p<0.0001; a decrease in CK between moment -24h and -1h and an increase between moment -1h and +24h (p<0.0001; and differences between winners and losers T levels, in moments -24h, -1h, 0h and +24h (p = 0.009 e p < 0.001, p = 0.005 e p = 0,001, T and C, respectively, in T/C in the moments -24h and 0h (p=0.006 and p=0.001, respectively and in GLU levels (p<0.0001 in the moment 0h. Therefore, it seems that an MMA fight leads to metabolic stress and muscle damage, regardless of the result of the fight. The coaches have now more biochemical and hormonal references and indicators in response to an MMA fight.

Central Venous Catheter-Related Bloodstream Infection with Kocuria kristinae in a Patient with Propionic Acidemia

Directory of Open Access Journals (Sweden)

Masato Kimura

2017-01-01

Full Text Available Kocuria kristinae is a catalase-positive, coagulase-negative, Gram-positive coccus found in the environment and in normal skin and mucosa in humans; however, it is rarely isolated from clinical specimens and is considered a nonpathogenic bacterium. We describe a case of catheter-related bacteremia due to K. kristinae in a young adult with propionic acidemia undergoing periodic hemodialysis. The patient had a central venous catheter implanted for total parenteral nutrition approximately 6 months prior to the onset of symptoms because of repeated acute pancreatitis. K. kristinae was isolated from two sets of blood cultures collected from the catheter. Vancomycin followed by cefazolin for 16 days and 5-day ethanol lock therapy successfully eradicated the K. kristinae bacteremia. Although human infections with this organism appear to be rare and are sometimes considered to result from contamination, physicians should not underestimate its significance when it is isolated in clinical specimens.

Glutathione-S-transferase-omega [MMA(V) reductase] knockout mice: Enzyme and arsenic species concentrations in tissues after arsenate administration

International Nuclear Information System (INIS)

Chowdhury, Uttam K.; Zakharyan, Robert A.; Hernandez, Alba; Avram, Mihaela D.; Kopplin, Michael J.; Aposhian, H. Vasken

2006-01-01

Inorganic arsenic is a human carcinogen to which millions of people are exposed via their naturally contaminated drinking water. Its molecular mechanisms of carcinogenicity have remained an enigma, perhaps because arsenate is biochemically transformed to at least five other arsenic-containing metabolites. In the biotransformation of inorganic arsenic, GSTO1 catalyzes the reduction of arsenate, MMA(V), and DMA(V) to the more toxic + 3 arsenic species. MMA(V) reductase and human (hGSTO1-1) are identical proteins. The hypothesis that GST-Omega knockout mice biotransformed inorganic arsenic differently than wild-type mice has been tested. The livers of male knockout (KO) mice, in which 222 bp of Exon 3 of the GSTO1 gene were eliminated, were analyzed by PCR for mRNA. The level of transcripts of the GSTO1 gene in KO mice was 3.3-fold less than in DBA/1lacJ wild-type (WT) mice. The GSTO2 transcripts were about two-fold less in the KO mouse. When KO and WT mice were injected intramuscularly with Na arsenate (4.16 mg As/kg body weight); tissues removed at 0.5, 1, 2, 4, 8, and 12 h after arsenate injection; and the arsenic species measured by HPLC-ICP-MS, the results indicated that the highest concentration of the recently discovered and very toxic MMA(III), a key biotransformant, was in the kidneys of both KO and WT mice. The highest concentration of DMA(III) was in the urinary bladder tissue for both the KO and WT mice. The MMA(V) reducing activity of the liver cytosol of KO mice was only 20% of that found in wild-type mice. There appears to be another enzyme(s) other than GST-O able to reduce arsenic(V) species but to a lesser extent. This and other studies suggest that each step of the biotransformation of inorganic arsenic has an alternative enzyme to biotransform the arsenic substrate

Towards the development of an enzyme replacement therapy for the metabolic disorder propionic acidemia

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Mahnaz Darvish-Damavandi

2016-09-01

Full Text Available Propionic acidemia (PA is a life-threatening disease caused by the deficiency of a mitochondrial biotin-dependent enzyme known as propionyl coenzyme-A carboxylase (PCC. This enzyme is responsible for degrading the metabolic intermediate, propionyl coenzyme-A (PP-CoA, derived from multiple metabolic pathways. Currently, except for drastic surgical and dietary intervention that can only provide partial symptomatic relief, no other form of therapeutic option is available for this genetic disorder. Here, we examine a novel approach in protein delivery by specifically targeting and localizing our protein candidate of interest into the mitochondrial matrix of the cells. In order to test this concept of delivery, we have utilized cell penetrating peptides (CPPs and mitochondria targeting sequences (MTS to form specific fusion PCC protein, capable of translocating and localizing across cell membranes. In vitro delivery of our candidate fusion proteins, evaluated by confocal images and enzymatic activity assay, indicated effectiveness of this strategy. Therefore, it holds immense potential in creating a new paradigm in site-specific protein delivery and enzyme replacement therapeutic for PA.

Emulsion Polymerization of MMA/BA in the Presence of Ionic Surface Active Monomers(Ⅰ)--Syntheses and Polymerization Reactivities of the Surfmers%离子型表面活性单体存在下的MMA/BA乳液聚合(Ⅰ)--表面活性单体的合成及其(共)聚合活性

Institute of Scientific and Technical Information of China (English)

张茂根; 翁志学; 黄志明; 毛昕; 潘祖仁

1999-01-01

合成了两种离子型表面活性单体(Surfmer)--磺化-十二醇-烯丙基甘油-丁二酸酯钠盐(ZC-L)和磺化-十二醇-甲基丙烯酰甘油-丁二酸酯钠盐(ZD-L).着重研究了ZC-L的结构、表面张力行为、均聚及共聚能力.实验结果表明,不同Surfmer用量以及不同固含量下,MMA/BA/Surfmer,MMA/Surfmer及BA/Surfmer共聚乳液的表面张力较高,说明Surfmer已通过共聚结合在乳胶粒上,乳液中残留甚少.对MMA/BA体系,ZC-L的共聚性能比ZD-L好.

Identification and Quantitation of Malonic Acid Biomarkers of In-Born Error Metabolism by Targeted Metabolomics

Science.gov (United States)

Ambati, Chandra Shekar R.; Yuan, Furong; Abu-Elheiga, Lutfi A.; Zhang, Yiqing; Shetty, Vivekananda

2017-05-01

Malonic acid (MA), methylmalonic acid (MMA), and ethylmalonic acid (EMA) metabolites are implicated in various non-cancer disorders that are associated with inborn-error metabolism. In this study, we have slightly modified the published 3-nitrophenylhydrazine (3NPH) derivatization method and applied it to derivatize MA, MMA, and EMA to their hydrazone derivatives, which were amenable for liquid chromatography- mass spectrometry (LC-MS) quantitation. 3NPH was used to derivatize MA, MMA, and EMA, and multiple reaction monitoring (MRM) transitions of the corresponding derivatives were determined by product-ion experiments. Data normalization and absolute quantitation were achieved by using 3NPH derivatized isotopic labeled compounds 13C2-MA, MMA-D3, and EMA-D3. The detection limits were found to be at nanomolar concentrations and a good linearity was achieved from nanomolar to millimolar concentrations. As a proof of concept study, we have investigated the levels of malonic acids in mouse plasma with malonyl-CoA decarboxylase deficiency (MCD-D), and we have successfully applied 3NPH method to identify and quantitate all three malonic acids in wild type (WT) and MCD-D plasma with high accuracy. The results of this method were compared with that of underivatized malonic acid standards experiments that were performed using hydrophilic interaction liquid chromatography (HILIC)-MRM. Compared with HILIC method, 3NPH derivatization strategy was found to be very efficient to identify these molecules as it greatly improved the sensitivity, quantitation accuracy, as well as peak shape and resolution. Furthermore, there was no matrix effect in LC-MS analysis and the derivatized metabolites were found to be very stable for longer time.

Surface self-assembly of fluorosurfactants during film formation of MMA/nBA colloidal dispersions.

Science.gov (United States)

Dreher, W R; Urban, M W

2004-11-23

These studies focus on the behavior of fluorosurfactants (FS) containing hydrophobic and ionic entities in the presence of methyl methacrylate/n-butyl acrylate (MMA/nBA) colloidal dispersions stabilized by sodium dodecyl sulfate (SDS). The presence of FS significantly not only alters the mobility of SDS in MMA/nBA films, but their hydrophobic and ionic nature results in self-assembly near the film-air (F-A) interface leading to different surface morphologies. Spherical islands and rodlike morphologies are formed which diminish the kinetic coefficient of friction of films by at least 3 orders of magnitude, and the presence of dual hydrophobic tails and an anionic head appears to have the largest effect on the surface friction. Using internal reflection IR imaging, these studies show that structural and chemical features of FS are directly related to their ability to migrate to the F-A interface and self-assemble to form specific morphological features. While the anionic nature of FS allows for SDS migration to the F-A interface and the formation of stable domains across the surface, intermolecular cohesion of nonionic FS allows for the formation of rodlike structures due to inability to form mixed micelles with SDS. These studies also establish the relationship between surface morphologies, kinetic coefficient of friction, and structural features of surfactants in the complex environments.

Enhancement of thermal and mechanical properties of poly(MMA-co-BA)/Cloisite 30B nanocomposites by ultrasound-assisted in-situ emulsion polymerization.

Science.gov (United States)

Sharma, Sachin; Kumar Poddar, Maneesh; Moholkar, Vijayanand S

2017-05-01

This study reports synthesis and characterization of poly(MMA-co-BA)/Cloisite 30B (organo-modified montmorillonite clay) nanocomposites by ultrasound-assisted in-situ emulsion polymerization. Copolymers have been synthesized with MMA:BA monomer ratio of 4:1, and varying clay loading (1-5wt% monomer). The poly(MMA-co-BA)/Cloisite 30B nanocomposites have been characterized for their thermal and mechanical properties. Ultrasonically synthesized nanocomposites have been revealed to possess higher thermal degradation resistance and mechanical strength than the nanocomposites synthesized using conventional techniques. These properties, however, show an optimum (or maxima) with clay loading. The maximum values of thermal and mechanical properties of the nanocomposites with optimum clay loading are as follows. Thermal degradation temperatures: T 10% =320°C (4wt%), T 50 =373°C (4wt%), maximum degradation temperature=384°C (4wt%); glass transition temperature=64.8°C (4wt%); tensile strength=20MPa (2wt%), Young's modulus=1.31GPa (2wt%), Percentage elongation=17.5% (1wt%). Enhanced properties of poly(MMA-co-BA)/Cloisite 30B nanocomposites are attributed to effective exfoliation and dispersion of clay nanoparticles in copolymer matrix due to intense micro-convection induced by ultrasound and cavitation. Clay platelets help in effective heat absorption with maximum surface interaction/adhesion that results in increased thermal resistivity of nanocomposites. Hindered motion of the copolymer chains due to clay platelets results in enhancement of tensile strength and Young's modulus of nanocomposite. Rheological (liquid) study of the nanocomposites reveals that nanocomposites have higher yield stress and infinite shear viscosity than neat copolymer. Nonetheless, nanocomposites still display shear thinning behavior - which is typical of the neat copolymer. Copyright © 2016 Elsevier B.V. All rights reserved.

The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 2: the evolving clinical phenotype.

Science.gov (United States)

Kölker, Stefan; Valayannopoulos, Vassili; Burlina, Alberto B; Sykut-Cegielska, Jolanta; Wijburg, Frits A; Teles, Elisa Leão; Zeman, Jiri; Dionisi-Vici, Carlo; Barić, Ivo; Karall, Daniela; Arnoux, Jean-Baptiste; Avram, Paula; Baumgartner, Matthias R; Blasco-Alonso, Javier; Boy, S P Nikolas; Rasmussen, Marlene Bøgehus; Burgard, Peter; Chabrol, Brigitte; Chakrapani, Anupam; Chapman, Kimberly; Cortès I Saladelafont, Elisenda; Couce, Maria L; de Meirleir, Linda; Dobbelaere, Dries; Furlan, Francesca; Gleich, Florian; González, Maria Julieta; Gradowska, Wanda; Grünewald, Stephanie; Honzik, Tomas; Hörster, Friederike; Ioannou, Hariklea; Jalan, Anil; Häberle, Johannes; Haege, Gisela; Langereis, Eveline; de Lonlay, Pascale; Martinelli, Diego; Matsumoto, Shirou; Mühlhausen, Chris; Murphy, Elaine; de Baulny, Hélène Ogier; Ortez, Carlos; Pedrón, Consuelo C; Pintos-Morell, Guillem; Pena-Quintana, Luis; Ramadža, Danijela Petković; Rodrigues, Esmeralda; Scholl-Bürgi, Sabine; Sokal, Etienne; Summar, Marshall L; Thompson, Nicholas; Vara, Roshni; Pinera, Inmaculada Vives; Walter, John H; Williams, Monique; Lund, Allan M; Garcia-Cazorla, Angeles; Garcia Cazorla, Angeles

2015-11-01

The disease course and long-term outcome of patients with organic acidurias (OAD) and urea cycle disorders (UCD) are incompletely understood. To evaluate the complex clinical phenotype of OAD and UCD patients at different ages. Acquired microcephaly and movement disorders were common in OAD and UCD highlighting that the brain is the major organ involved in these diseases. Cardiomyopathy [methylmalonic (MMA) and propionic aciduria (PA)], prolonged QTc interval (PA), optic nerve atrophy [MMA, isovaleric aciduria (IVA)], pancytopenia (PA), and macrocephaly [glutaric aciduria type 1 (GA1)] were exclusively found in OAD patients, whereas hepatic involvement was more frequent in UCD patients, in particular in argininosuccinate lyase (ASL) deficiency. Chronic renal failure was often found in MMA, with highest frequency in mut(0) patients. Unexpectedly, chronic renal failure was also observed in adolescent and adult patients with GA1 and ASL deficiency. It had a similar frequency in patients with or without a movement disorder suggesting different pathophysiology. Thirteen patients (classic OAD: 3, UCD: 10) died during the study interval, ten of them during the initial metabolic crisis in the newborn period. Male patients with late-onset ornithine transcarbamylase deficiency were presumably overrepresented in the study population. Neurologic impairment is common in OAD and UCD, whereas the involvement of other organs (heart, liver, kidneys, eyes) follows a disease-specific pattern. The identification of unexpected chronic renal failure in GA1 and ASL deficiency emphasizes the importance of a systematic follow-up in patients with rare diseases.

EFFECT OF THE PHASE STRUCTURE EVOLUTION ON THE PROPERTIES OF FILMS FORMED FROM PBA/P(ST-CO-MMA)COMPOSITE LATEX

Institute of Scientific and Technical Information of China (English)

无

2008-01-01

A group of heterogeneous latexes poly(butyl acrylate)/poly(styrene-co-methyl methacrylate)(PBA/P(St-co-MMA))were prepared by a semi-continuous seeded emulsion polymerization process under monomer starved conditions.The glass transition temperature(Tg)and the mechanical properties of the film formed from the composite latex changed with the evolution of the particle morphology.A photon transmission method was used to monitor the phase structure evolution of films which were prepared from core-shell PBA/P(St-co-MMA)latex at room temperature and annealed at 383 K above Tg of the polymers.In addition,the changes of the surface of the film formed from the composite latex with time at 383 K were observed by AFM.The evidence illustrated that the film formed from the core-shell latex particles was metastable.The rearrangement of the phases could occur under proper conditions.

Reaction kinetics of irradiation prepolymerized MMA-PU IPN by 5DXC FTIR

International Nuclear Information System (INIS)

Wu Yiming; Zhang Zhiping; Luo Ning

2000-01-01

The reaction kinetics of irradiation-prepolymerized MMA-PU (polyether) IPNs have been studied by FTIR. The results indicate that the polymerization of each component in the IPN follows its normal distinct reaction mechanism with no mutual interference. Increasing the concentration of TMPTAM (crosslinking agent of PMMA) increased the formation rate of PMMA, while the formation rate of PU networks remained almost the same. Increasing the concentration of TMP (crosslinking agent of PU) increased the formation rate of PU, while the formation rate of PMMA networks decreased. The formation rate of PU was obviously faster than that of PMMA. A theory for the cage effect of the PU network has been proposed. (author)

Cu(ll) mediated ATRP of MMA by using a novel tetradentate amine ligand with oligo(ethylene glycol) pendant groups

NARCIS (Netherlands)

Becer, C.R.; Hoogenboom, R.; Founier, D.; Schubert, U.S.

2007-01-01

A novel tetradentate amine ligand namely N,N,N,N,N;,N;-hexaoligo(ethylene glycol) triethylenetetramine (HOEGTETA) was employed in the homogenous ATRP of MMA in anisole using CuBr and CuBr2 as the catalyst and ethyl 2-bromoisobutyrate (EBiB) as an initiator. The effect of the polymerization

Data of PCL-b-P(MMA-DMAEMA2 characterization and related assays

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Camila Franco

2017-12-01

Full Text Available The data presented here are related to the research paper entitled “PCL-b-P(MMA-co-DMAEMA2 new triblock copolymer for novel pH-sensitive nanocapsules intended for drug delivery to tumors” by Franco et al. [1]. Characterization data of PCL-diol, macroinitiator Br-PCL-Br, homopolymers (PMMA and PDMAEMA and copolymers (batch 1 and batch 2 analyzed by FTIR, SEC and NMR, as well as, characterization of PCL-NS formulation by laser diffraction and DLS analysis, initial nanocapsule formulations and 1C-NC and 2C-NC formulations, including hydrodynamic diameter at different pH media, and DMSO cytotoxicity. Keywords: Methacrylic copolymer, Polycaprolactone, Nanocapsules, pH-sensitive, Cell viability

Molecular cloning of L-methylmalonyl-CoA mutase: Gene transfer and analysis of mut cell lines

International Nuclear Information System (INIS)

Ledley, F.D.; Lumetta, M.; Nguyen, P.N.; Kolhouse, J.F.; Allen, R.H.

1988-01-01

L-Methylmalonyl-CoA mutase (MCM, EC 5.4.99.2) is a mitochondrial adenosylcobalamin-requiring enzyme that catalyzes the isomerization of L-methylmalonyl-CoA to succinyl-CoA. This enzyme is deficient in methylmalonic acidemia, an often fatal disorder of organic acid metabolism. Antibody against human placental MCM was used to screen human placenta and liver cDNA expression libraries for MCM cDNA clones. One clone expressed epitopes that could affinity-purify antibodies against MCM. A cDNA corresponding in length to the mRNA was obtained and introduced into COS cells by DNA-mediated gene transfer. Cells transformed with this clone expressed increased levels of MCM enzymatic activity. RNA blot analysis of cells genetically deficient in MCM indicates that several deficient cell lines have a specific decrease in the amount of hybridizable mRNA. These data confirm the authenticity of the MCM cDNA clone, establish the feasibility of constituting MCM activity by gene transfer for biochemical analysis and gene therapy, and provide a preliminary picture of the genotypic spectrum underlying MCM deficiency

Europe Agrees on Common Strategy to Initiate Study of LSA/MMA

Science.gov (United States)

1998-09-01

Council Specifies ESO's Role in Planning In an extraordinary meeting at the ESO Headquarters, the ESO Council today endorsed ESO's involvement in the planning of a major new astronomical facility in the southern hemisphere. Some years from now, the Large Southern Array/Millimetre Array (LSA/MMA) may become the world's prime sub-mm/mm radio observatory [1] at a pristine site at 5000 m altitude in the Chilean Andes, not very far from the VLT Paranal Observatory. Background One of the highest-priority items in astronomy today is a large millimetre-wavelength array. This would be a millimetre counterpart to the ESO VLT and the NASA/ESA Hubble Space Telescope (HST), with similar scientific objectives and comparable high angular resolution and sensitivity. An antenna array with about 10,000 m 2 area would provide very high sensitivity and angular resolution, compatible with that of the VLT and HST. Such a large collecting area implies an array with many antennas and baselines, which give the added advantage of fast, high-quality images. The site must be high, dry, large, and flat - a high plateau in the Atacama desert is ideal, and has the great advantage of being in the southern hemisphere, important for compatibility with the VLT. Thus, discussions in Europe have focussed on a "Large Southern Array" (LSA) . The scientific case for such a telescope is overwhelming. It would be able to study the origins of galaxies and stars: the epoch of first galaxy formation and the evolution of galaxies at later stages, including the dust-obscured star-forming galaxies that the HST and VLT cannot see, and all phases of star formation hidden away in dusty molecular clouds. But the LSA will go far beyond these main science drivers - it will have a major impact on virtually all areas of astronomy, and make millimetre astronomy accessible to all astronomers. It may well have as big a user community as the VLT itself. European involvement in millimetre astronomy Europe already has a

Gene structure and mutations of glutaryl-coenzyme A dehydrogenase: impaired association of enzyme subunits that is due to an A421V substitution causes glutaric acidemia type I in the Amish.

OpenAIRE

Biery, B. J.; Stein, D. E.; Morton, D. H.; Goodman, S. I.

1996-01-01

The structure of the human glutaryl coenzyme A dehydrogenase (GCD) gene was determined to contain 11 exons and to span approximately 7 kb. Fibroblast DNA from 64 unrelated glutaric acidemia type I (GA1) patients was screened for mutations by PCR amplification and analysis of SSCP. Fragments with altered electrophoretic mobility were subcloned and sequenced to detect mutations that caused GA1. This report describes the structure of the GCD gene, as well as point mutations and polymorphisms fou...

Hampered Vitamin B12 Metabolism in Gaucher Disease?

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Luciana Hannibal PhD

2017-02-01

Full Text Available Untreated vitamin B 12 deficiency manifests clinically with hematological abnormalities and combined degeneration of the spinal cord and polyneuropathy and biochemically with elevated homocysteine (Hcy and methylmalonic acid (MMA. Vitamin B 12 metabolism involves various cellular compartments including the lysosome, and a disruption in the lysosomal and endocytic pathways induces functional deficiency of this micronutrient. Gaucher disease (GD is characterized by dysfunctional lysosomal metabolism brought about by mutations in the enzyme beta-glucocerebrosidase (Online Mendelian Inheritance in Man (OMIM: 606463; Enzyme Commission (EC 3.2.1.45, gene: GBA1 . In this study, we collected and examined available literature on the associations between GD, the second most prevalent lysosomal storage disorder in humans, and hampered vitamin B 12 metabolism. Results from independent cohorts of patients show elevated circulating holotranscobalamin without changes in vitamin B 12 levels in serum. Gaucher disease patients under enzyme replacement therapy present normal levels of Hcy and MMA. Although within the normal range, a significant increase in Hcy and MMA with normal serum vitamin B 12 was documented in treated GD patients with polyneuropathy versus treated GD patients without polyneuropathy. Thus, a functional deficiency of vitamin B 12 caused by disrupted lysosomal metabolism in GD is a plausible mechanism, contributing to the neurological form of the disorder but this awaits confirmation. Observational studies suggest that an assessment of vitamin B 12 status prior to the initiation of enzyme replacement therapy may shed light on the role of vitamin B 12 in the pathogenesis and progression of GD.

PREPARATION AND PROPERTIES OF MMA/1-PROPYLMETHACRYLATE-POSS COPOLYMER WITH ATOM TRANSFER RADICAL POLYMERIZATION

Institute of Scientific and Technical Information of China (English)

He-xin Zhang; Ho-young Lee; Young-jun Shin; Dong-ho Lee; Seok Kyun Noh

2008-01-01

The methyl methacrylate(MMA)/1-propylmethacrylate-polyhedral oligomeric silsesquioxane(PM-POSS) copolymers were synthesized via atom transfer radical polymerization with CuBr as catalyst.The unreacted PM-POSS monomer could be removed completely by washing the copolymerization product with n-hexane.The copolymers were characterized with 1H-NMR,X-ray diffraction,difierential scanning calorimetry,thermogravimetric analysis and gel permeatlon chromatography.With increasing PM-POSS feed ratio.the total conversion increased while the glass transition temperatures of copolymer decreased.The thermogravimetric analysis demonstrated that the thermal stability of copolymer improved slightly with PM-POSS addition.The molecular weight of copolymers increased with incorporation of PM-POSS.

Investigation of P(VDF-TrFE)/ZrO{sub 2}-MMA polymer composites applied to radiation shielding

Energy Technology Data Exchange (ETDEWEB)

Fontainha, C.C.P. [Depto. de Engenharia Nuclear - UFMG, Av. Antonio Carlos 6627, 31270-970 Belo Horizonte, MG (Brazil); Baptista Neto, A.T.; Santos, A.P.; Faria, L.O. [Centro de Desenvolvimento da Tecnologia Nuclear, Av. Antonio Carlos 6627, C.P. 941, 30270-901, Belo Horizonte, MG (Brazil)

2015-07-01

Exposure to high radiation dose in medical diagnostic imaging procedures can lead patients to suffer tissue damaging. However, there are several studies that identify significant dose reduction with the use of radiation protective attenuators, minimizing the delivered dose in the region that covers the main beam, while preserving the diagnostic quality of the generated image. Most radiation attenuator materials are produced from shielding metal containing composites, whose efficiency is the goal of investigations around the world. In this context, polymeric materials were chosen for this investigation in order to provide light-weighted and flexible protective composites, a must in personal protective shielding. Therefore, this work is concerned to the investigation of poly(vinylidene fluoride - try-fluor-ethylene) [P(VDF-TrFE)] copolymers mixed with zirconia nanoparticles. The resulting polymer composites, prepared with 1, 2, 3, 5 and 10 at.% of ZrO{sub 2} nanoparticles, were investigated for application as protective shielding in some interventional radiology procedures. Two variety of composites were produced, one using pure ZrO{sub 2} nanoparticles and the other using sol-gel route with zirconium butoxide as the precursor for zirconium oxide nano-clusters. The P(VDFTrFE)/ ZrO2-MMA polymer composites produced by sol-gel route have provided a much better dispersion of the pure ZrO{sub 2} material into the P(VDF-TrFE) host matrix. UV-Vis and FTIR spectrometry and differential scanning calorimetry (DSC) were used to characterize the composite samples. FTIR data reveal a possible link between the MMA monomers with the P(VDF-TrFE) chain through shared C=O bonds. The radiation shielding characterization was conducted by using a 70 kV x-rays beam which is applicable, for instances, in catheter angiography. The results demonstrate that composites with 10% of ZrO{sub 2}, and only 1.0 mm thick, can attenuate 60% of the x-rays beam. The composite density was evaluated to be

Functional characterization of novel genotypes and cellular oxidative stress studies in propionic acidemia.

Science.gov (United States)

Gallego-Villar, Lorena; Pérez-Cerdá, Celia; Pérez, Belén; Abia, David; Ugarte, Magdalena; Richard, Eva; Desviat, Lourdes R

2013-09-01

Propionic acidemia (PA), caused by a deficiency of the mitochondrial biotin dependent enzyme propionyl-CoA carboxylase (PCC) is one of the most frequent organic acidurias in humans. PA is caused by mutations in either the PCCA or PCCB genes encoding the α- and β-subunits of the PCC enzyme which are assembled as an α6β6 dodecamer. In this study we have investigated the molecular basis of the defect in ten fibroblast samples from PA patients. Using homology modeling with the recently solved crystal structure of the PCC holoenzyme and a eukaryotic expression system we have analyzed the structural and functional effect of novel point mutations, also revealing a novel splice defect by minigene analysis. In addition, we have investigated the contribution of oxidative stress to cellular damage measuring reactive oxygen species (ROS) levels and apoptosis parameters in patient fibroblasts, as recent studies point to a secondary mitochondrial dysfunction as pathophysiological mechanism in this disorder. The results show an increase in intracellular ROS content compared to controls, correlating with the activation of the JNK and p38 signaling pathways. Highest ROS levels were present in cells harboring functionally null mutations, including one severe missense mutation. This work provides molecular insight into the pathogenicity of PA variants and indicates that oxidative stress may be a major contributing factor to the cellular damage, supporting the proposal of antioxidant strategies as novel supplementary therapy in this rare disease.

Effect of RAMEB on Soap-free Emulsion Polymerization of MMA%无规甲基化β-环糊精对甲基丙烯酸甲酯无皂乳液聚合影响

Institute of Scientific and Technical Information of China (English)

杨学红; 胡杰; 周志平; 魏伟

2011-01-01

采用溶液法制备了无规甲基化β-环糊精(RAMEB)/甲基丙烯酸甲酯(MMA)包合物,利用紫外-可见光谱、热重-差热分析等检测手段表明RAMEB与MMA可以形成摩尔比为1∶ 1的包合物,从而使MMA的热稳定性大大提高.通过RAMEB与 MMA的包合作用研究了RAMEB对MMA无皂乳液聚合反应的影响.结果表明,当RAMEB的加入量为4.2×10-4 mol时,体系在75 ℃反应30 min时,单体转化率达89.2%,比同一时间下没有加入RAMEB的空白样的单体转化率提高了30.6%.当RAMEB的加入量为8.4×10-4 mol时,聚合反应速率比空白样低,单体的最终转化率与空白样差不多.同时,RAMEB的引入可以使PMMA微球粒径变大,随着RAMEB加入量的增加,聚合物微球的大小越来越均匀.%The inclusion complex of methyl methacrylate (MMA) with randomly methylated βcyclodextrin (RAMEB) was synthesized by the solvent method and characterized by UV, TG- DSC. The molar ratio method shows that the 1:1 inclusion compound has formed between RAMEB and MMA. The TG - DSC analysis shows that RAMEB and MMA have formed a steady inclusion and the stability of MMA has increased remarkably. By the inclusion of REMEB and MMA ,we investigated the influence of RAMEB on the soap-free emulsion polymerization of MMA. It is found that when the addition of RAMEB is 4. 2 × 10 -4 mol,and the conversion of MMA reached 89. 2％ in 30 min at 75 ℃. Compared to the no addition of RAMEB, the conversion increased 30. 6％. When the addition of RAMEB is 8.4 × 10-4 mol, the polymerization speed decelerated and the monomer conversion was almost the same compared to the no addition of RAMEB. The addition of RAMEB will increase the particle size of PMMA. With the increase of RAMEB,PMMA particles are getting more and more uniform.

Mutation in mitochondrial complex IV subunit COX5A causes pulmonary arterial hypertension, lactic acidemia, and failure to thrive.

Science.gov (United States)

Baertling, Fabian; Al-Murshedi, Fathiya; Sánchez-Caballero, Laura; Al-Senaidi, Khalfan; Joshi, Niranjan P; Venselaar, Hanka; van den Brand, Mariël Am; Nijtmans, Leo Gj; Rodenburg, Richard Jt

2017-06-01

COX5A is a nuclear-encoded subunit of mitochondrial respiratory chain complex IV (cytochrome c oxidase). We present patients with a homozygous pathogenic variant in the COX5A gene. Clinical details of two affected siblings suffering from early-onset pulmonary arterial hypertension, lactic acidemia, failure to thrive, and isolated complex IV deficiency are presented. We show that the variant lies within the evolutionarily conserved COX5A/COX4 interface domain, suggesting that it alters the interaction between these two subunits during complex IV biogenesis. In patient skin fibroblasts, the enzymatic activity and protein levels of complex IV and several of its subunits are reduced. Lentiviral complementation rescues complex IV deficiency. The monomeric COX1 assembly intermediate accumulates demonstrating a function of COX5A in complex IV biogenesis. A potential therapeutic lead is demonstrated by showing that copper supplementation leads to partial rescue of complex IV deficiency in patient fibroblasts. © 2017 Wiley Periodicals, Inc.

Candida albicans biofilms and MMA surface treatment influence the adhesion of soft denture liners to PMMA resin

Directory of Open Access Journals (Sweden)

Martinna de Mendonça e Bertolini

2014-01-01

Full Text Available The effect of Candida albicans biofilms and methyl methacrylate (MMA pretreatment on the bond strength between soft denture liners and polymethyl methacrylate (PMMA resin was analyzed. Specimens were prepared and randomly divided with respect to PMMA pretreatment, soft liner type (silicone-based or PMMA-based, and presence or absence of a C. albicans biofilm. Samples were composed of a soft denture liner bonded between two PMMA bars. Specimens (n = 10 were incubated to produce a C. albicans biofilm or stored in sterile PBS for 12 days. The tensile bond strength test was performed and failure type was determined using a stereomicroscope. Surface roughness (SR and scanning electron microscopy (SEM analysis were performed on denture liners (n = 8. Highest bond strength was observed in samples containing a silicone-based soft liner and stored in PBS, regardless of pretreatment (p < 0.01. Silicone-based specimens mostly underwent adhesive failures, while samples containing PMMA-based liners predominantly underwent cohesive failures. The silicone-based specimens SR decreased after 12 days of biofilm accumulation or PBS storage, while the SR of PMMA-based soft liners increased (p < 0.01. The PMMA-based soft liners surfaces presented sharp valleys and depressions, while silicone-based specimens surfaces exhibited more gentle features. In vitro exposure to C. albicans biofilms reduced the adhesion of denture liners to PMMA resin, and MMA pretreatment is recommended during relining procedures.

Direct Production of a Novel Iron-Based Nanocomposite from the Laser Pyrolysis of Fe(CO5/MMA Mixtures: Structural and Sensing Properties

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R. Alexandrescu

2010-01-01

Full Text Available Iron/iron oxide-based nanocomposites were prepared by IR laser sensitized pyrolysis of Fe(CO5 and methyl methacrylate (MMA mixtures. The morphology of nanopowder analyzed by TEM indicated that mainly core-shell structures were obtained. X-ray diffraction techniques evidence the cores as formed mainly by iron/iron oxide crystalline phases. A partially degraded (carbonized polymeric matrix is suggested for the coverage of the metallic particles. The nanocomposite structure at the variation of the laser density and of the MMA flow was studied. The new materials prepared as thick films were tested for their potential for acting as gas sensors. The temporal variation of the electrical resistance in presence of NO2, CO, and CO2, in dry and humid air was recorded. Preliminary results show that the samples obtained at higher laser power density exhibit rather high sensitivity towards NO2 detection and NO2 selectivity relatively to CO and CO2. An optimum working temperature of 200°C was found.

Influences of Electrolytes on Soap-Free P(ST-MMA-AA) Emulsion Polymerization

Institute of Scientific and Technical Information of China (English)

Zeping LI; Ronglong LI; Yi DU; Chengyou KAN; Deshan LIU

2005-01-01

@@ 1Introduction Functional polymer microspheres are kinds of polymer particles with special structures, morphologies or functional groups[1] , and have been gained much attention because of their specific properties and their application since 1980s. Although some researches have investigated that the latex particle size and its distribution,as well as the stability of polymerization and the resultant latex were strongly influenced by introducing electrolyte into the emulsion polymerization system[2] , few of them focused on the systematic study of electrolytes on the soap-free emulsion polymerization, which is considered as a conventional approach to synthesize functional polymer microspheres with clean surfaces[2]. In this presentation, the influences of variety and dosage of electrolytes on soap-free emulsion polymerization of St, MMA and AA were studied, and a series of micron or submicron sized latex particles with narrow distribution were obtained.

Identification of ABC transporters acting in vitamin B12 metabolism in Caenorhabditis elegans.

Science.gov (United States)

McDonald, Megan K; Fritz, Julie-Anne; Jia, Dongxin; Scheuchner, Deborah; Snyder, Floyd F; Stanislaus, Avalyn; Curle, Jared; Li, Liang; Stabler, Sally P; Allen, Robert H; Mains, Paul E; Gravel, Roy A

2017-12-01

Vitamin B 12 (cobalamin, Cbl) is a micronutrient essential to human health. Cbl is not utilized as is but must go through complex subcellular and metabolic processing to generate two cofactor forms: methyl-Cbl for methionine synthase, a cytosolic enzyme; and adenosyl-Cbl for methylmalonyl-CoA mutase, a mitochondrial enzyme. Some 10-12 human genes have been identified responsible for the intracellular conversion of Cbl to cofactor forms, including genes that code for ATP-binding cassette (ABC) transporters acting at the lysosomal and plasma membranes. However, the gene for mitochondrial uptake is not known. We hypothesized that ABC transporters should be candidates for other uptake and efflux functions, including mitochondrial transport, and set out to screen ABC transporter mutants for blocks in Cbl utilization using the nematode roundworm Caenorhabditis elegans. Thirty-seven mutant ABC transporters were screened for the excretion of methylmalonic acid (MMA), which should result from loss of Cbl transport into the mitochondria. One mutant, wht-6, showed elevated MMA excretion and reduced [ 14 C]-propionate incorporation, pointing to a functional block in methylmalonyl-CoA mutase. In contrast, the wht-6 mutant appeared to have a normal cytosolic pathway based on analysis of cystathionine excretion, suggesting that cytosolic methionine synthase was functioning properly. Further, the MMA excretion in wht-6 could be partially reversed by including vitamin B 12 in the assay medium. The human ortholog of wht-6 is a member of the G family of ABC transporters. We propose wht-6 as a candidate for the transport of Cbl into mitochondria and suggest that a member of the corresponding ABCG family of ABC transporters has this role in humans. Our ABC transporter screen also revealed that mrp-1 and mrp-2 mutants excreted lower MMA than wild type, suggesting they were concentrating intracellular Cbl, consistent with the cellular efflux defect proposed for the mammalian MRP1 ABC

Safety in Mixed Martial Arts: a 7-Year Review of Cancelled MMA Bouts in Calgary, Alberta, During the Pre-bout Medical Examination Period.

Science.gov (United States)

Curran-Sills, Gwynn

2018-01-12

Presently, there is no literature that examines the reasons for the cancellation of amateur or professional mixed martial arts (MMA) bouts. The purpose of this study was to review the circumstances that lead to the cancellation of MMA bouts by Calgary ringside physicians during the pre-bout examination period and to identify any emerging patterns that may guide the regulatoin of this sport. The case-series  was constructed from the Calgary Combative Sports Commission pre-bout examination records and the medical records submitted by each athlete from January 2010 to December 2016. Cancelled bouts in the pre-bout examination periods represented 5.4% of all MMA bouts in Calgary. A total of 25 reasons lead to bout cancellation and included the following: failure to obtain required neuroimaging (28.0%), neuroimaging abnormalities (24.0%), incomplete routine screening investigations (16.0%), exceeding maximum weight differential between the two athletes (16.0%), injury in the pre-competition period (8.0%), dehydration (4.0%), and ECG abnormalities (4.0%). The abnormalities on neuroimaging (n of 6) included the following: post traumatic gliosis on MRI (n = 1, 16.7%), flares diffusely and findings consistent with microhemorrhage on MRI (n = 1, 16.7%), chronic orbital fracture with fat pad extrusion on CT (n = 2, 33.3%), lacunar infarct on MRI (1), and unspecified MRI abnormality (n = 1, 16.7%). Twenty-two athletes had bouts cancelled and of these three athletes had their bouts stopped for two reasons. The following recommendations are presented and include: the creation of guidelines regarding pre- and post-bout neuroimaging, the implementation of industry-wide minimum medical screening standards, the adoption of a longitudinal approach to weight monitoring, the development of competent ringside physician groups, and active oversight by the Combative Sports Commission during the matchmaking process.

The Polymerization of MMA and ST to Prepare Material with Gradient Refractive Index in Electric Field

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Yao Huang

2015-01-01

Full Text Available Light scattering material with gradient refractive index was prepared under the electrical field by taking methyl methacrylate (MMA monomer as the matrix with the addition of a little preheated styrene (ST and peroxidation benzoin formyl (BPO. The material obtained under electrical field presented different transmittance and molecular weight at different parts of the cylindrical sample along the axis of the direction of electric field which led to the layering phenomenon and gradient refractive index. The disparity of molecular weight between different layers can be as much as 230 thousand. There were several peaks in the figure of GPC test of the sample under electric field. This proved that there were polymers with different molecular weights in the sample. Therefore, it can be concluded that electrical field has a significant effect on polymerization.

Study on Soap-free P(MMA-EA-AA/MAA) Latex Particles With Narrow Size Distribution

Institute of Scientific and Technical Information of China (English)

K. Kang; C. Y. Kan; Y. Du; D. S. Liu

2005-01-01

@@ 1Introduction In the past decades, more and more studies have been focused on the synthesis of monodisperse particles with different diameter by special polymerization technique. In 1980' s, Ugelstad, et al[1] invented two-step swelling method to prepare monodisperse microsphere with large size more than 1 μm. In the following decade, Okubo and his coworkers[2] synthesized monodisperse crosslinked polymer particles above 3 μm using one-step dynamic swelling method. New method has been developed to produce particles more than 50 μm in diameter with a standard deviation of less than 2%[3]. Up to now, most of the monodisperse particles were usually prepared by polymerization of St in the presence of surfactants. In this presentation, sub-micro sized P (MMA-EA-AA/MAA) particles with narrow size distribution were prepared by seeded emulsion polymerization in the absence of any surfactant materials.

[Occupational exposure of welders to ultraviolet and "blue light" radiation emitted during TIG and MMA welding based on field measurements].

Science.gov (United States)

Wolska, Agnieszka

2013-01-01

The aim of the study was to present the results of welders' occupational exposure to "blue light" and UV radiation carried out at industrial workstations during TIG and MMA welding. Measurements were performed at 13 workstations (TIG welding: 6; MMA welding: 7), at which different welding parameters and materials were used. The radiation level was measured using a wide-range radiometer and a set of detectors, whose spectral responses were adequately fit to particular hazard under study. The measurement points corresponded with the location of eye and hand. The highest values of eye irradiance were found for aluminum TIG welding. Effective irradiance of actinic UV was within the range E(s) = 7.79-37.6 W/m2; UVA total irradiance, E(UVA) = 18-53.1 W/m2 and effective blue-light irradiance E(B) = 35-67 W/m2. The maximum allowance time ranged from 1.7 to 75 s, which means that in some cases even unintentional very short eye exposure can exceed MPE. The influence of welded material and the type of electrode coating on the measured radiation level were evidenced. The exceeded value of MPE for photochemical hazard arising for the eyes and skin was found at all measured workstations. Welders should use appropriately the eye and face protective equipment and avoid direct staring at welding arc when starting an arc-welding operation. Besides, the lack of head and neck skin protection can induce acute and chronic harmful health effects. Therefore, an appropriate wear of personal protective equipment is essential for welders' health.

Occupational exposure of welders to ultraviolet and "blue light" radiation emitted during TIG and MMA welding based on field measuremants

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Agnieszka Wolska

2013-02-01

Full Text Available Background: The aim of the study was to present the results of welders' occupational exposure to "blue light" and UV radiation carried out at industrial workstations during TIG and MMA welding. Materials and methods: Measurements were performed at 13 workstations (TIG welding: 6; MMA welding: 7, at which different welding parameters and materials were used. The radiation level was measured using a wide-range radiometer and a set of detectors, whose spectral responses were adequately fit to particular hazard under study. The measurement points corresponded with the location of eye and hand. Results: The highest values of eye irradiance were found for aluminum TIG welding. Effective irradiance of actinic UV was within the range Es = 7.79-37.6 W/m2; UVA total irradiance, EUVA = 18-53.1 W/m2 and effective blue-light irradiance EB = 35-67 W/m2. The maximum allowance time ranged from 1.7 to 75 s, which means that in some cases even unintentional very short eye exposure can exceed MPE. Conclusions: The influence of welded material and the type of electrode coating on the measured radiation level were evidenced. The exceeded value of MPE for photochemical hazard arising for the eyes and skin was found at all measured workstations. Welders should use appropriately the eye and face protective equipment and avoid direct staring at welding arc when starting an arcwelding operation. Besides, the lack of head and neck skin protection can induce acute and chronic harmful health effects. Therefore, an appropriate wear of personal protective equipment is essential for welders' health. Med Pr 2013;64(1:69–82

Synthesis of fluorinated acrylate and MMA by solution polymerization%氟代丙烯酸酯/MMA共聚物合成工艺研究

Institute of Scientific and Technical Information of China (English)

惠远峰; 张立东; 许崇利; 包海峰

2010-01-01

通过溶液聚合合成了氟代丙烯酸酯与甲基丙烯酸甲酯(MMA)的共聚物,并初步表征了产物结构.最佳反应温度80℃,单体浓度50%,引发剂用量1.5%,氟单体与MMA的比例为1:3,此时转化率最好.

Sodium bicarbonate treatment during transient or sustained lactic acidemia in normoxic and normotensive rats.

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Franco Valenza

Full Text Available INTRODUCTION: Lactic acidosis is a frequent cause of poor outcome in the intensive care settings. We set up an experimental model of lactic acid infusion in normoxic and normotensive rats to investigate the systemic effects of lactic acidemia per se without the confounding factor of an underlying organic cause of acidosis. METHODOLOGY: Sprague Dawley rats underwent a primed endovenous infusion of L(+ lactic acid during general anesthesia. Normoxic and normotensive animals were then randomized to the following study groups (n = 8 per group: S sustained infusion of lactic acid, S+B sustained infusion+sodium bicarbonate, T transient infusion, T+B transient infusion+sodium bicarbonate. Hemodynamic, respiratory and acid-base parameters were measured over time. Lactate pharmacokinetics and muscle phosphofructokinase enzyme's activity were also measured. PRINCIPAL FINDINGS: Following lactic acid infusion blood lactate rose (P<0.05, pH (P<0.05 and strong ion difference (P<0.05 drop. Some rats developed hemodynamic instability during the primed infusion of lactic acid. In the normoxic and normotensive animals bicarbonate treatment normalized pH during sustained infusion of lactic acid (from 7.22 ± 0.02 to 7.36 ± 0.04, P<0.05 while overshoot to alkalemic values when the infusion was transient (from 7.24 ± 0.01 to 7.53 ± 0.03, P<0.05. When acid load was interrupted bicarbonate infusion affected lactate wash-out kinetics (P<0.05 so that blood lactate was higher (2.9 ± 1 mmol/l vs. 1.0 ± 0.2, P<0.05, group T vs. T+B respectively. The activity of phosphofructokinase enzyme was correlated with blood pH (R2 = 0.475, P<0.05. CONCLUSIONS: pH decreased with acid infusion and rose with bicarbonate administration but the effects of bicarbonate infusion on pH differed under a persistent or transient acid load. Alkalization affected the rate of lactate disposal during the transient acid load.

Contributions of enriched cereal-grain products, ready-to-eat cereals, and supplements to folic acid and vitamin B-12 usual intake and folate and vitamin B-12 status in US children: National Health and Nutrition Examination Survey (NHANES), 2003-2006.

Science.gov (United States)

Yeung, Lorraine F; Cogswell, Mary E; Carriquiry, Alicia L; Bailey, Lynn B; Pfeiffer, Christine M; Berry, Robert J

2011-01-01

US children consume folic acid from multiple sources. These sources may contribute differently to usual intakes above the age-specific tolerable upper intake level (UL) for folic acid and to folate and vitamin B-12 status. We estimated usual daily folic acid intakes above the UL and adjusted serum and red blood cell folate, serum vitamin B-12, homocysteine, and methylmalonic acid (MMA) concentrations in US children by age group and by the following 3 major folic acid intake sources: enriched cereal-grain products (ECGP), ready-to-eat cereals (RTE), and supplements containing folic acid (SUP). We analyzed data in 4 groups of children aged 1-3, 4-8, 9-13, and 14-18 y from the National Health and Nutrition Examination Survey (NHANES), 2003-2006 (n = 7161). A total of 19-48% of children consumed folic acid from ECGP only. Intakes above the UL varied from 0-0.1% of children who consumed ECGP only to 15-78% of children who consumed ECGP+RTE+SUP. In children aged 1-8 y, 99-100% of those who consumed ≥ 200 μg folic acid/d from supplements exceeded their UL. Although consumption of RTE or SUP with folic acid was associated with higher mean folate and vitamin B-12 concentrations and, in some older children, with lower homocysteine and MMA concentrations. Our data suggest that the majority of US children consume more than one source of folic acid. Postfortification, the consumption of RTE or SUP increases usual daily intakes and blood concentrations of folate and vitamin B-12.

Ultrasonic Induced Microemulsion Polymerization of MMA%超声辐照引发MMA微乳液聚合

Institute of Scientific and Technical Information of China (English)

廖勇勤; 王琪; 王良文

2001-01-01

研究了超声波引发甲基丙烯酸甲酯(MMA)的微乳液聚合. 辐照40 min时单体转化率高达90%. 透射电镜观察发现, PMMA微乳液平均粒径为36.5 nm, 粒径分布窄, 表明超声波引发是制备PMMA微乳液的有效方法. 采用分光光度计对微乳液聚合过程中乳胶粒的形成和大小进行了间接表征, 研究了超声功率输出、乳化剂、助乳化剂、单体和引发剂对MMA微乳液聚合的影响.

A fast and simple solid phase microextraction coupled with gas chromatography-triple quadrupole mass spectrometry method for the assay of urinary markers of glutaric acidemias.

Science.gov (United States)

Naccarato, Attilio; Gionfriddo, Emanuela; Elliani, Rosangela; Sindona, Giovanni; Tagarelli, Antonio

2014-10-30

The analysis of characteristic urinary acidic markers such as glutaric, 3-hydroxyglutaric, 2-hydroxyglutaric, adipic, suberic, sebacic, ethylmalonic, 3-hydroxyisovaleric and isobutyric acid constitutes the recommended follow-up testing procedure for glutaric acidemia type 1 (GA-1) and type 2 (GA-2). The goal of the work herein presented is the development of a fast and simple method for the quantification of these biomarkers in human urine. The proposed analytical approach is based on the use of solid phase microextraction (SPME) combined with gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS) afterward a rapid derivatization of acidic moieties by propyl chloroformate, propanol and pyridine. Trueness and precision of the proposed protocol, tested at 5, 30 and 80mgl -1 , provided satisfactory values: recoveries were in the range between 72% and 116% and the relative standard deviations (RSD%) were between 0.9% and 18% (except for isobutyric acid at 5mgl -1 ). The LOD values achieved by the proposed method ranged between 1.0 and 473μgl -1 . Copyright © 2014 Elsevier B.V. All rights reserved.

Performance Evaluation of MMA7260QT and ADXL345 on Self Balancing Robot

Directory of Open Access Journals (Sweden)

Djoko Purwanto

2013-03-01

Full Text Available A Self Balancing Robot (SBR controller needs to detect platform inclination. For this purpose, an accelerometer is used. From various types of accelerometer, we can divide into digital and analog ones. The problem is how to select the right type for the SBR.This paper evaluates the performance of the ADXL345 and the MMA7260QT. The Arduino is used to read data from the sensor and send it to PC for plotting. Both sensors use the lowest sensitivity. The sensors are evaluated with three criteria, i.e. stationary, dynamical response and collaborating with ITG3200 3-axis gyroscope for Kalman Filter fusion. For stationary criterion, the ADXL345 is better than the other sensor for all stationary position. For dynamical response, both sensors suffer from the noise due to acceleration of the platform. The sensors do not only sense the gravity but also the acceleration of the platform when it is moved. But the noise level for the ADXL345 is lower than the other. Using Kalman Filter makes both sensors show good performance for a SBR application. If three criteria are combined with hardware aspect, then the authors recommend using the ADXL345. Besides, it has several useful features to handle abrupt acceleration.

Carglumic acid enhances rapid ammonia detoxification in classical organic acidurias with a favourable risk-benefit profile: a retrospective observational study.

Science.gov (United States)

Valayannopoulos, Vassili; Baruteau, Julien; Delgado, Maria Bueno; Cano, Aline; Couce, Maria L; Del Toro, Mireia; Donati, Maria Alice; Garcia-Cazorla, Angeles; Gil-Ortega, David; Gomez-de Quero, Pedro; Guffon, Nathalie; Hofstede, Floris C; Kalkan-Ucar, Sema; Coker, Mahmut; Lama-More, Rosa; Martinez-Pardo Casanova, Mercedes; Molina, Agustin; Pichard, Samia; Papadia, Francesco; Rosello, Patricia; Plisson, Celine; Le Mouhaer, Jeannie; Chakrapani, Anupam

2016-03-31

Isovaleric aciduria (IVA), propionic aciduria (PA) and methylmalonic aciduria (MMA) are inherited organic acidurias (OAs) in which impaired organic acid metabolism induces hyperammonaemia arising partly from secondary deficiency of N-acetylglutamate (NAG) synthase. Rapid reduction in plasma ammonia is required to prevent neurological complications. This retrospective, multicentre, open-label, uncontrolled, phase IIIb study evaluated the efficacy and safety of carglumic acid, a synthetic structural analogue of NAG, for treating hyperammonaemia during OA decompensation. Eligible patients had confirmed OA and hyperammonaemia (plasma NH3 > 60 μmol/L) in ≥1 decompensation episode treated with carglumic acid (dose discretionary, mean (SD) first dose 96.3 (73.8) mg/kg). The primary outcome was change in plasma ammonia from baseline to endpoint (last available ammonia measurement at ≤18 hours after the last carglumic acid administration, or on Day 15) for each episode. Secondary outcomes included clinical response and safety. The efficacy population (received ≥1 dose of study drug and had post-baseline measurements) comprised 41 patients (MMA: 21, PA: 16, IVA: 4) with 48 decompensation episodes (MMA: 25, PA: 19, IVA: 4). Mean baseline plasma ammonia concentration was 468.3 (±365.3) μmol/L in neonates (29 episodes) and 171.3 (±75.7) μmol/L in non-neonates (19 episodes). At endpoint the mean plasma NH3 concentration was 60.7 (±36.5) μmol/L in neonates and 55.2 (±21.8) μmol/L in non-neonates. Median time to normalise ammonaemia was 38.4 hours in neonates vs 28.3 hours in non-neonates and was similar between OA subgroups (MMA: 37.5 hours, PA: 36.0 hours, IVA: 40.5 hours). Median time to ammonia normalisation was 1.5 and 1.6 days in patients receiving and not receiving concomitant scavenger therapy, respectively. Although patients receiving carglumic acid with scavengers had a greater reduction in plasma ammonia, the endpoint ammonia levels were

Luminescent sensitization and blue shift emission of Ir(ppy){sub 2}(VPHD) by copolymerization with MMA

Energy Technology Data Exchange (ETDEWEB)

An Baoli, E-mail: blan@staff.shu.edu.cn [Department of Chemistry, College of Science, Shanghai University, Shanghai 200444 (China); Dai Fanzeng; Zhang Yanling; Song Jian; Huang, Xiao-Di [Department of Chemistry, College of Science, Shanghai University, Shanghai 200444 (China); Xu, Jia-Qiang, E-mail: xujiaqiang@shu.edu.cn [Department of Chemistry, College of Science, Shanghai University, Shanghai 200444 (China); State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

2011-08-15

Ir(ppy){sub 2}(VPHD) (ppy=2-phenyl pyridine, VPHD=6-(4-vinylphenyl)-2,4-hexanedione) was copolymerized with methyl methacrylate (MMA). The copolymer had high quantum yield of 52.3{+-}0.5% in dilute ethyl acetate solution, and the yield increased around 45% than that of the iridium monomer. The maximum emission peaks for the copolymers shifted from 515 to 489 nm while the iridium complex content was less than 0.005 mol% in the feed. The blue emission at 489 nm and the green emission at 520 nm were analyzed by Lorenz function. They are attributed to {sup 1}MLCT and {sup 3}MLCT emissions, respectively. - Highlights: > PMMA-Ir(ppy){sub 2}(VPHD) as luminescent material with high yield of 53%. > The blue color emission at 489 nm from {sup 1}MLCT in conformity with Lorenz function. > The quantum yield for the copolymer increases 45% than that of the iridium monomer. > The {sup 3}MLCT Ex. intensity versus the monomer concentration is in conformity with Boltzmann function.

Nationwide survey of extended newborn screening by tandem mass spectrometry in Taiwan.

Science.gov (United States)

Niu, Dau-Ming; Chien, Yin-Hsiu; Chiang, Chuan-Chi; Ho, Hui-Chen; Hwu, Wuh-Liang; Kao, Shu-Min; Chiang, Szu-Hui; Kao, Chuan-Hong; Liu, Tze-Tze; Chiang, Hung; Hsiao, Kwang-Jen

2010-10-01

In Taiwan, during the period March 2000 to June 2009, 1,495,132 neonates were screened for phenylketonuria (PKU) and homocystinuria (HCU), and 1,321,123 neonates were screened for maple syrup urine disease (MSUD), methylmalonic academia (MMA), medium-chain acyl-coenzyme A (CoA) dehydrogenase (MCAD) deficiency, isovaleric academia (IVA), and glutaric aciduria type 1 (GA-1) using tandem mass spectrometry (MS/MS). In a pilot study, 592,717 neonates were screened for citrullinemia, 3-methylcrotonyl-CoA carboxylase deficiency (3-MCC) and other fatty acid oxidation defects in the MS/MS newborn screening. A total of 170 newborns and four mothers were confirmed to have inborn errors of metabolism. The overall incidence was approximately 1/5,882 (1/6,219 without mothers). The most common inborn errors were defects of phenylalanine metabolism [five classic PKU, 20 mild PKU, 40 mild hyperphenylalaninemia (HPA), and 13 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency]. MSUD was the second most common amino acidopathy and, significantly, most MSUD patients (10/13) belonged to the Austronesian aboriginal tribes of southern Taiwan. The most frequently detected among organic acid disorders was 3-MCC deficiency (14 newborns and four mothers). GA-1 and MMA were the second most common organic acid disorders (13 and 13 newborns, respectively). In fatty acid disorders, five carnitine transport defect (CTD), five short-chain acyl-CoA dehydrogenase deficiency (SCAD), and two medium-chain acyl-CoA dehydrogenase (MCAD) deficiency were confirmed. This is the largest case of MS/MS newborn screening in an East-Asian population to date. We hereby report the incidences and outcomes of metabolic inborn error diseases found in our nationwide MS/MS newborn screening program.

Gene structure and mutations of glutaryl-coenzyme A dehydrogenase: impaired association of enzyme subunits that is due to an A421V substitution causes glutaric acidemia type I in the Amish.

Science.gov (United States)

Biery, B J; Stein, D E; Morton, D H; Goodman, S I

1996-11-01

The structure of the human glutaryl coenzyme A dehydrogenase (GCD) gene was determined to contain 11 exons and to span approximately 7 kb. Fibroblast DNA from 64 unrelated glutaric acidemia type I (GA1) patients was screened for mutations by PCR amplification and analysis of SSCP. Fragments with altered electrophoretic mobility were subcloned and sequenced to detect mutations that caused GA1. This report describes the structure of the GCD gene, as well as point mutations and polymorphisms found in 7 of its 11 exons. Several mutations were found in more than one patient, but no one prevalent mutation was detected in the general population. As expected from pedigree analysis, a single mutant allele causes GA1 in the Old Order Amish of Lancaster County, Pennsylvania. Several mutations have been expressed in Escherichia coli, and all produce diminished enzyme activity. Reduced activity in GCD encoded by the A421V mutation in the Amish may be due to impaired association of enzyme subunits.

Succinate-CoA ligase deficiency due to mutations in SUCLA2 and SUCLG1

DEFF Research Database (Denmark)

Carrozzo, Rosalba; Verrigni, Daniela; Rasmussen, Magnhild

2016-01-01

BACKGROUND: The encephalomyopathic mtDNA depletion syndrome with methylmalonic aciduria is associated with deficiency of succinate-CoA ligase, caused by mutations in SUCLA2 or SUCLG1. We report here 25 new patients with succinate-CoA ligase deficiency, and review the clinical and molecular findings...... deficiency of complexes I and IV, but normal histological and biochemical findings in muscle did not preclude a diagnosis of succinate-CoA ligase deficiency. In five patients, the urinary excretion of methylmalonic acid was only marginally elevated, whereas elevated plasma methylmalonic acid was consistently...

SIMULTANEOUS MEASUREMENT OF FREE RADICAL DECAY IN POLYMERIZATION OF MMA INITIATED BY AIBN USING ESR AND ITS KINETIC MODEL

Institute of Scientific and Technical Information of China (English)

Ping Xia; Qing-song Hu; Xiao-lan Qian; Xul-in Jiang; De-yue Yan

2001-01-01

The kinetics of free radical decay in the polymerization of MMA initiated by AIBN was studied by means of ESR spectroscopy. It was found that the curves of radical decay are strongly associated with the reaction temperature, the initiator concentration and the solvent. In the case of the radical polymerization carried out at high temperature or in solution, the radical concentration first reached a maximum, then declined monotonously with reaction time. It was also found that the greater the amount of initiator or the higher the temperature, the more rapidly the radicals decay. When the bulk polymerization was implemented at a relatively low temperature, the curves of radical decay became more complicated, i.e.,the radical concentration rapidly rose to a maximum, then dropped to a minimum, finally increased again with reaction time.Taking into account the diffusion effect, a semi-empirical equation is suggested to describe the kinetics of propagating radical decay.

Speciation of the immediately mobilisable As(III), As(V), MMA and DMA in river sediments by high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry following ultrasonic extraction

International Nuclear Information System (INIS)

Huerga, A.; Lavilla, I.; Bendicho, C.

2005-01-01

In this work, a fast method is developed for the speciation of As(III), As(V), MMA and DMA in the immediately mobilisable fraction of river sediments (i.e. water-soluble and phosphate-exchangeable) by high performance liquid chromatography-hydride generation-atomic fluorescence detection (HPLC-HG-AFD) after extraction using focused ultrasound. The influence of relevant parameters influencing an ion-pairing chromatographic separation following isocratic elution (i.e. amount of MeOH in the mobile phase, ion pair reagent concentration, pH, flow rate) was studied. Focused ultrasound transmitted from an ultrasonic probe provided the same extractable contents as conventional extraction with no changes in the species distribution. The effect of the drying step over extraction of As species was investigated. The following drying procedures were compared: freeze-, oven-, microwave- and air-drying. No influence of the drying operation on the water-extractable fraction was observed. However, freeze- and air-drying yielded significantly higher phosphate-extractable amounts of As(III) and As(V) as compared to oven and microwaves. Detection limits for the As species were in the range 1.3-4.1 ng/g for the water-soluble fraction and 1.6-4.8 ng/g for the phosphate buffer exchangeable fraction. The method was applied to the speciation of immediately mobilisable As(III), As(V), DMA and MMA in 11 sediment samples collected along the beds of the Louro River (southern Galicia, Spain)

Dietary supplement use and smoking are important correlates of biomarkers of water-soluble vitamin status after adjusting for sociodemographic and lifestyle variables in a representative sample of US adults1,2,3

Science.gov (United States)

Pfeiffer, Christine M.; Sternberg, Maya R.; Schleicher, Rosemary L.; Rybak, Michael E.

2016-01-01

Biochemical indicators of water-soluble vitamin (WSV) status have been measured in a nationally representative sample of the US population in NHANES 2003–2006. To examine whether demographic differentials in nutritional status were related to and confounded by certain variables, we assessed the association of sociodemographic (age, sex, race-ethnicity, education, income) and lifestyle variables (dietary supplement use, smoking, alcohol consumption, BMI, physical activity) with biomarkers of WSV status in adults (≥20 y): serum and RBC folate, serum pyridoxal-5′-phosphate (PLP), serum 4-pyridoxic acid, serum total cobalamin (B-12), plasma total homocysteine (tHcy), plasma methylmalonic acid (MMA), and serum ascorbic acid. Age (except for PLP) and smoking (except for MMA) were generally the strongest significant correlates of these biomarkers (|r| ≤0.43) and together with supplement use explained more of the variability as compared to the other covariates in bivariate analysis. In multiple regression models, sociodemographic and lifestyle variables together explained from 7% (B-12) to 29% (tHcy) of the biomarker variability. We observed significant associations for most biomarkers (≥6 out of 8) with age, sex, race-ethnicity, supplement use, smoking, and BMI; and for some biomarkers with PIR (5/8), education (1/8), alcohol consumption (4/8), and physical activity (5/8). We noted large estimated percent changes in biomarker concentrations between race-ethnic groups (from −24% to 20%), between supplement users and nonusers (from −12% to 104%), and between smokers and nonsmokers (from −28% to 8%). In summary, age, sex, and race-ethnic differentials in biomarker concentrations remained significant after adjusting for sociodemographic and lifestyle variables. Supplement use and smoking were important correlates of biomarkers of WSV status. PMID:23576641

Dietary supplement use and smoking are important correlates of biomarkers of water-soluble vitamin status after adjusting for sociodemographic and lifestyle variables in a representative sample of U.S. adults.

Science.gov (United States)

Pfeiffer, Christine M; Sternberg, Maya R; Schleicher, Rosemary L; Rybak, Michael E

2013-06-01

Biochemical indicators of water-soluble vitamin (WSV) status were measured in a nationally representative sample of the U.S. population in NHANES 2003-2006. To examine whether demographic differentials in nutritional status were related to and confounded by certain variables, we assessed the association of sociodemographic (age, sex, race-ethnicity, education, income) and lifestyle (dietary supplement use, smoking, alcohol consumption, BMI, physical activity) variables with biomarkers of WSV status in adults (aged ≥ 20 y): serum and RBC folate, serum pyridoxal-5'-phosphate (PLP), serum 4-pyridoxic acid, serum total cobalamin (vitamin B-12), plasma total homocysteine (tHcy), plasma methylmalonic acid (MMA), and serum ascorbic acid. Age (except for PLP) and smoking (except for MMA) were generally the strongest significant correlates of these biomarkers (|r| ≤ 0.43) and together with supplement use explained more of the variability compared with the other covariates in bivariate analysis. In multiple regression models, sociodemographic and lifestyle variables together explained from 7 (vitamin B-12) to 29% (tHcy) of the biomarker variability. We observed significant associations for most biomarkers (≥ 6 of 8) with age, sex, race-ethnicity, supplement use, smoking, and BMI and for some biomarkers with PIR (5 of 8), education (1 of 8), alcohol consumption (4 of 8), and physical activity (5 of 8). We noted large estimated percentage changes in biomarker concentrations between race-ethnic groups (from -24 to 20%), between supplement users and nonusers (from -12 to 104%), and between smokers and nonsmokers (from -28 to 8%). In summary, age, sex, and race-ethnic differentials in biomarker concentrations remained significant after adjusting for sociodemographic and lifestyle variables. Supplement use and smoking were important correlates of biomarkers of WSV status.

Pregnant women of South Asian ethnicity in Canada have substantially lower vitamin B12 status compared with pregnant women of European ethnicity.

Science.gov (United States)

Schroder, Theresa H; Sinclair, Graham; Mattman, Andre; Jung, Benjamin; Barr, Susan I; Vallance, Hilary D; Lamers, Yvonne

2017-09-01

Maternal vitamin B12 (B12) status has been inversely associated with adverse pregnancy outcomes and positively with fetal growth and infant development. South Asians, Canada's largest ethnic minority, are prone to B12 deficiency. Yet, data are lacking on B12 status in South Asian pregnant women in North America. We sought to determine B12 status, using multiple biomarkers, in 1st and 2nd trimester pregnant women of South Asian and, for comparison, European ethnicity living in Vancouver, Canada. In this retrospective cohort study, total B12, holotranscobalamin (holoTC), methylmalonic acid (MMA), and total homocysteine concentrations were quantified in two routinely collected (mean gestational week: 11·5 (range 8·3-13·9) and 16·5 (range 14·9-20·9)), banked serum samples of 748 healthy pregnant South Asian (n 371) and European (n 377) women. South Asian pregnant women had significantly lower B12 status than European pregnant women at both time points, as indicated by lower serum total B12 and holoTC concentrations, and higher MMA concentrations (all P≤0·001). The largest difference, which was substantial (Cohen's d≥0·5), was observed in mean serum total B12 concentrations (1st trimester: 189 (95 % CI 180, 199) v. 246 (95 % CI 236, 257) pmol/l; 2nd trimester: 176 (95 % CI 168, 185) v. 226 (95 % CI 216, 236) pmol/l). Further, South Asian ethnicity was a significant negative predictor of B12 status during pregnancy. South Asian women living in Vancouver have substantially lower B12 status during early pregnancy. Future research identifying predictors and health consequences of this observed difference is needed to allow for targeted interventions.

Helicobacter pylori seropositivity's association with markers of iron, 1-carbon metabolism, and antioxidant status among US adults: a structural equations modeling approach.

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May A Beydoun

Full Text Available We tested a model in which Helicobacter pylori seropositivity (Hps predicted iron status, which in turn acted as a predictor for markers of 1-C metabolism that were then allowed to predict antioxidant status.National Health and Nutrition Examination Surveys (NHANES 1999-2000 cross-sectional data among adults aged 20-85 y were analyzed (n = 3,055. Markers of Hps, iron status (serum ferritin and transferrin saturation (TS; 1-C metabolism (serum folate (FOLserum, B-12, total homocysteine (tHcy, methylmalonic acid (MMA and antioxidant status (vitamins A and E were entered into a structural equations model (SEM.Predictors of Hps included older age, lower education and income, racial/ethnic groups (lowest among Non-Hispanic Whites, and lifetime cigarette smoking. SEM modeling indicated that Hps had a direct inverse relationship with iron status (combining serum ferritin and TS which in turn was positively related to 1-C metabolites (higher serum folate, B-12 or lower tHcy/MMA that were positively associated with antioxidant status (combining serum vitamins A and E. Another pathway that was found bypassed 1-C metabolites (Hps → Iron_st → Antiox. The sum of all indirect effects from Hps combining both pathways and the other indirect pathways in the model (Hps → Iron_st → OneCarbon; Hps →OneCarbon →Antiox was estimated at β = -0.006±0.003, p<0.05.In sum, of the total effect of H. pylori seropositivity on antioxidant status, two significant indirect pathways through Iron status and 1-Carbon metabolites were found. Randomized controlled trials should be conducted to uncover the concomitant causal effect of H. pylori eradication on improving iron status, folate, B-12 and antioxidant status among H. pylori seropositive individuals.

Efficient automated synthesis of 2-(5-["1"8F]fluoropentyl)-2-methylmalonic acid (["1"8F]ML-10) on a commercial available ["1"8F]FDG synthesis module

International Nuclear Information System (INIS)

Liu, Shaoyu; Nie, Dahong; Jiang, Shende; Tang, Ganghua

2017-01-01

["1"8F]ML-10 (2-(5-["1"8F]fluoro-pentyl)-2-methylmalonic acid) is a small molecule positron emission tomography (PET) probe for apoptosis imaging. Automated synthesis of ["1"8F]ML-10 was developed by using two different purification methods through a direct saponification procedure on a modified commercial ["1"8F]Fluoro-2-Deoxyglucose (["1"8F]FDG) synthesizer. C18 purification method 1: The final ["1"8F]ML-10 solution containing ethanol was obtained with radiochemical yields of 60±5% (n=5) at the end of bombardment (EOB) and radiochemical purity of 98% in 35 min. Al_2O_3 and SCX purification method 2: To avoid possible side effects of a conventional ethanol-containing formulation, an new ethanol-free solution of ["1"8F]ML-10 was also developed, the radiochemical yields was 50±5% (n=5, EOB) within 45 min and the radiochemical purity was 98%. - Highlights: • The production of ["1"8F]ML-10 was optimized by using a straightforward saponification procedure. • Automated synthesis was performed on a commonly FDG synthesis module. • An ethanol-containing ["1"8F]ML-10 formulation was obtained with high radiochemical yield in a shorter time. • An ethanol-free formulation method of ["1"8F]ML-10 was also developed.

An unusual insertion/deletion in the gene encoding the β-subunit of propionyl-CoA carboxylase is a frequent mutation in Caucasian propionic acidemia

International Nuclear Information System (INIS)

Tahara, T.; Kraus, J.P.; Rosenberg, L.E.

1990-01-01

Propionic acidemia is an inherited disorder of organic acid metabolism that is caused by deficiency of propionly-CoA carboxylase. Affected patients fall into two complementation groups, pccA and pccBC (subgroups B, C, and BC), resulting from deficiency of the nonidentical α and β subunits of PCC, respectively. The authors have detected an unusual insertion/deletion in the DNA of patients from the pccBC and pccC subgroups that replaces 14 nucleotides in the coding sequence of the β subunit with 12 nucleotides unrelated to this region of the gene. Among 14 unrelated Caucasian patients in the pccBc complementation group, this unique mutation was found in 8 of 28 mutant alleles examined. Mutant allele-specific oligonucleotide hybridization to amplified genomic DNAs revealed that the inserted 12 nucleotides do not originate in an ∼1000-bp region around the mutation. In the course of the investigation, they identified another mutation in the same exon: a 3-bp in-frame deletion that eliminates one of two isoleucine codons immediately preceding the Msp I site. Two unrelated patients were compound heterozygotes for this single-codon deletion and for the insertion/deletion described above. They conclude that either there is a propensity for the PCC β-subunit gene to undergo mutations of this sort at this position or, more likely, the mutations in all of the involved Caucasian patients have a common origin in preceding generations

P(MMA-EMA Random Copolymer Electrolytes Incorporating Sodium Iodide for Potential Application in a Dye-Sensitized Solar Cell

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Nurul Akmaliah Dzulkurnain

2015-02-01

Full Text Available Polymer electrolytes based on 90 wt% of methyl methacrylate and 10 wt% of ethyl methacrylate (90MMA-co-10EMA incorporating different weight ratios of sodium iodide were prepared using the solution casting method. The complexation between salt and copolymer host has been investigated using Fourier transform infrared spectroscopy. The ionic conductivity and thermal stability of the electrolytes were measured using impedance spectroscopy and differential scanning calorimetry, respectively. Scanning electron microscopy was used to study the morphology of the polymer electrolytes. The ionic conductivity and glass transition temperature increased up to 20 wt% of sodium iodide (5.19 × 10−6 S·cm−1 and decreased with the further addition of salt concentration, because of the crosslinked effect. The morphology behavior of the highest conducting sample also showed smaller pores compared to the other concentration. The total ionic transference number proved that this system was mainly due to ions, and the electrochemical stability window was up to 2.5 V, which is suitable for a dye-sensitized solar cell application. This sample was then tested in a dye-sensitized solar cell and exhibited an efficiency of 0.62%.

Preparation of nano composite latex of poly(butyl acrylate-co-methyl methacrylate) P (BA-co-MMA) and layered double hydroxide (LDH) by mini emulsion polymerization; Preparacao de latex nanocomposito de poli(acrilato de butila-co-metacrilato de metila) P (BA-co-MMA) e hidroxido duplo lamelar (HDL) por meio da tecnica de polimerizacao em miniemulsao

Energy Technology Data Exchange (ETDEWEB)

Silva, Rodrigo D; Lona, Liliane M.F., E-mail: liliane@feq.unicamp.br [Universidade Estadual de Campinas - Unicamp, Faculdade de Engenharia Quimica, SP (Brazil); Dube, Marc A [Universidade de Ottawa. Departamento de Engenharia Quimica e Biologica, Ottawa, ON (Canada)

2011-07-01

In the present work, the synthesis of polymeric nonconsumption (PNCs) of P(BA-coMMA) and layered LDH through mini emulsion polymerization (MEP) was studied. The commercial organically modified LDH Perkalite F100S was used as filler and octadecyl acrylate (ODA) as costabilizer of the mini emulsions. Two types of surfactant, a cationic and nonionic one, were investigated and the cationic one could not stabilize the system when the LDH was present. The polymerization kinetics was not significantly affected by the presence of LDH which kept the pH of the system constant during the reaction. The dispersion of the inorganic material in the polymeric matrix was evaluated by X-ray diffraction which suggested exfoliation of the LDH. (author)

几个二价稀土金属配合物的催化甲基丙烯酸甲酯聚合反应活性研究%Catalytic Activities of Some Organolanthanide(Ⅱ) Complexes on Methyl Methacrylate (MMA) Polymerization

Institute of Scientific and Technical Information of China (English)

周双六; 钱慧民; 陈国栋; 凡家喜

2008-01-01

研究了二价稀土金属配合物(η5:η1-C9H6CH2CH2CH2NMe2)2YbⅡ(1),[{η5:η5:η1-(C9H5CH2SiMe2NC4H8)2}EuII2(μ-Cl)]2[μ-η3:η5:η1:η3:η5:η1-(C9H5CH2SiMe2NC4H8)2]·C7H8·(C6H6)0.5(2),and[η5:η1-C9H6CH2SiMe2NC4H8]2YbⅡ(3)催化甲基丙烯酸甲酯聚合活性.探索了催化剂与MMA单体摩尔比、溶剂的极性、温度对MMA聚合反应的影响.%The catalytic activities of the organolanthanide(Ⅱ) complexes(η5:η1-C9H6CH2CH2CH2NMe2)2YbII (1),[{η5:η5:η1-(C9H5CH2SiMe2NC4H8)2}EuII2(μ-Cl)]2[μ-η3:η5:η1:η3:η5:η1-(C9H5CH2SiMe2NC4H8)2]·C7H8·(C6H6)0.5 (2), and [η5:η1-C9H6CH2SiMe2NC4H8]2YbⅡ(3) on methyl methacrylate (MMA) polymerization have been studied. The catalyst/MMA monomer mole ratio, solvents, and temperature effects on MMA polymerization were also examined.

Homocysteine as a potential biochemical marker for depression in elderly stroke survivors

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Michaela C. Pascoe

2012-04-01

Full Text Available Background: Elderly stroke survivors have been reported to be at risk of malnutrition and depression. Vitamin B-related metabolites such as methylmalonic acid and homocysteine have been implicated in depression. Objective: We conducted a study exploring the relationship between homocysteine and post-stroke depression. Design: Three methodologies were used: Observational cohort study of elderly Swedish patients (n=149 1.5 years post-stroke, assessed using Diagnostic and Statistical Manual of Mental Disorders, Montgomery Åsberg Depression Rating Scale and serum blood levels of methylmalonic acid and homocysteine. Results: Homocysteine significantly correlated with depressive symptomatology in stroke survivors (β = 0.18*. Individuals with abnormal levels of methylmalonic acid and homocysteine were almost twice more likely to show depressive symptomatology than those with normal levels (depressive symptoms 22%; no depressive symptoms 12%. Comparison of methylmalonic acid and homocysteine levels with literature data showed fewer stroke survivors had vitamin deficiency than did reference individuals (normal range 66%; elevated 34%. Conclusions: Homocysteine is significantly associated with depressive symptomatology in elderly Swedish stroke survivors.

Feasibility of adjunct therapeutic hypothermia treatment for hyperammonemia and encephalopathy due to urea cycle disorders and organic acidemias.

Science.gov (United States)

Lichter-Konecki, Uta; Nadkarni, Vinay; Moudgil, Asha; Cook, Noah; Poeschl, Johannes; Meyer, Michael T; Dimmock, David; Baumgart, Stephen

2013-08-01

Children with urea cycle disorders (UCDs) or organic acidemias (OAs) and acute hyperammonemia and encephalopathy are at great risk for neurological injury, developmental delay, intellectual disability, and death. Nutritional support, intravenous alternative pathway therapy, and dialysis are used to treat severe hyperammonemia associated with UCDs and nutritional support and dialysis are used to treat severe hyperammonemia in OAs. Brain protective treatment while therapy is initiated may improve neurological and cognitive function for the lifetime of the child. Animal experiments and small clinical trials in hepatic encephalopathy caused by acute liver failure suggest that therapeutic hypothermia provides neuroprotection in hyperammonemia associated encephalopathy. We report results of an ongoing pilot study that assesses if whole body cooling during rescue treatment of neonates with acute hyperammonemia and encephalopathy is feasible and can be conducted safely. Adjunct whole body therapeutic hypothermia was conducted in addition to standard treatment in acutely encephalopathic, hyperammonemic neonates with UCDs and OAs requiring dialysis. Therapeutic hypothermia was initiated using cooling blankets as preparations for dialysis were underway. Similar to standard therapeutic hypothermia treatment for neonatal hypoxic ischemic encephalopathy, patients were maintained at 33.5°C±1°C for 72h, they were then slowly rewarmed by 0.5°C every 3h over 18h. In addition data of age-matched historic controls were collected for comparison. Seven patients were cooled using the pilot study protocol and data of seven historic controls were reviewed. All seven patients survived the initial rescue and cooling treatment, 6 patients were discharged home 2-4weeks after hospitalization, five of them feeding orally. The main complication observed in a majority of patients was hypotension. Adjunct therapeutic hypothermia for neonates with UCDs and OAs receiving standard treatment was

Simultaneous speciation of arsenic (As(III), MMA, DMA, and As(V)) and selenium (Se(IV), Se(VI), and SeCN{sup -}) in petroleum refinery aqueous streams

Energy Technology Data Exchange (ETDEWEB)

Tonietto, Gisele B.; Godoy, Jose M.; Oliveira, Ana Cristina [Pontificia Universidade Catolica do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Souza, Marcia V. de [Petrobras/Cenpes, Research and Development Center, Rio de Janeiro (Brazil)

2010-07-15

High-performance liquid chromatography (HPLC) coupled to an ICP-MS with an octapole reaction system (ORS) has been used to carry out quantitative speciation of selenium (Se) and arsenic (As) in the stream waters of a refining process. The argon dimers interfering with the {sup 78}Se and {sup 80}Se isotopes were suppressed by pressurizing the octapole chamber with 3.1 mL min{sup -1} H{sub 2} and 0.5 mL min{sup -1} He. Four arsenic species arsenite - As(III), arsenate (As(V)), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) - and three inorganic Se species - selenite Se(IV), selenate Se(VI), and selenocyanate (SeCN{sup -}) - were separated in a single run by ion chromatography (IC) using gradient elution with 100 mmol L{sup -1} NH{sub 4}NO{sub 3}, pH 8.5, adjusted by addition of NH{sub 3}, as eluent. Repeatabilities of peak position and of peak area evaluation were better than 1% and about 3%, respectively. Detection limits (as 3{sigma} of the baseline noise) were 81, 56, and 75 ng L{sup -1} for Se(IV), Se(VI), and SeCN{sup -}, respectively, and 22, 19, 25, and 16 ng L{sup -1} for As(III), As(V), MMA, and DMA, respectively. Calibration curve R {sup 2} values ranged between 0.996 and 0.999 for the arsenic and selenium species. Column recovery for ion chromatography was calculated to be 97 {+-} 6% for combined arsenic species and 98 {+-} 3% for combined selenium species. Because certified reference materials for As and Se speciation studies are still not commercially available, in order to check accuracy and precision the method was applied to certified reference materials, BCR 714, BCR 1714, and BCR 715 and to two different refinery samples - inlet and outlet wastewater. The method was successfully used to study the quantitative speciation of selenium and arsenic in petroleum refinery wastewaters. (orig.)

Cobalamin status during normal pregnancy and postpartum: a longitudinal study comprising 406 danish women

DEFF Research Database (Denmark)

Milman, N; Byg, KE; Bergholt, T

2006-01-01

-) cobalamin, P-methylmalonic acid and P-homocysteine was measured at 18, 32 and 39 wk gestation and 8 wk postpartum during lactation. RESULTS: P-cobalamin showed a gradual, significant decline during pregnancy (P ... and 8 wk postpartum median values were 225, 172, 161 and 319 pmol/L, respectively. P-methylmalonic displayed a gradual, significant increase during pregnancy as well as postpartum (P homocysteine demonstrated...

Methylmalonic Acid Test

Science.gov (United States)

... Factor Antibody Iron Iron Tests JAK2 Mutation Kidney Stone Analysis Kidney Stone Risk Panel KRAS Mutation Lactate Lactate Dehydrogenase (LD) ... in Previous Reviews Clarke, W. and Dufour, D. R., Editors (2006). Contemporary Practice in Clinical Chemistry, AACC ...

Topology Optimization of Constrained Layer Damping on Plates Using Method of Moving Asymptote (MMA Approach

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Zheng Ling

2011-01-01

Full Text Available Damping treatments have been extensively used as a powerful means to damp out structural resonant vibrations. Usually, damping materials are fully covered on the surface of plates. The drawbacks of this conventional treatment are also obvious due to an added mass and excess material consumption. Therefore, it is not always economical and effective from an optimization design view. In this paper, a topology optimization approach is presented to maximize the modal damping ratio of the plate with constrained layer damping treatment. The governing equation of motion of the plate is derived on the basis of energy approach. A finite element model to describe dynamic performances of the plate is developed and used along with an optimization algorithm in order to determine the optimal topologies of constrained layer damping layout on the plate. The damping of visco-elastic layer is modeled by the complex modulus formula. Considering the vibration and energy dissipation mode of the plate with constrained layer damping treatment, damping material density and volume factor are considered as design variable and constraint respectively. Meantime, the modal damping ratio of the plate is assigned as the objective function in the topology optimization approach. The sensitivity of modal damping ratio to design variable is further derived and Method of Moving Asymptote (MMA is adopted to search the optimized topologies of constrained layer damping layout on the plate. Numerical examples are used to demonstrate the effectiveness of the proposed topology optimization approach. The results show that vibration energy dissipation of the plates can be enhanced by the optimal constrained layer damping layout. This optimal technology can be further extended to vibration attenuation of sandwich cylindrical shells which constitute the major building block of many critical structures such as cabins of aircrafts, hulls of submarines and bodies of rockets and missiles as an

Folic acid fortification: why not vitamin B12 also?

Science.gov (United States)

Selhub, Jacob; Paul, Ligi

2011-01-01

Folic acid fortification of cereal grains was introduced in many countries to prevent neural tube defect occurrence. The metabolism of folic acid and vitamin B12 intersect during the transfer of the methyl group from 5-methyltetrahydrofolate to homocysteine catalyzed by B12-dependent methioine synthase. Regeneration of tetrahydrofolate via this reaction makes it available for synthesis of nucleotide precursors. Thus either folate or vitamin B12 deficiency can result in impaired cell division and anemia. Exposure to extra folic acid through fortification may be detrimental to those with vitamin B12 deficiency. Among participants of National Health And Nutrition Examination Survey with low vitamin B12 status, high serum folate (>59 nmol/L) was associated with higher prevalence of anemia and cognitive impairment when compared with normal serum folate. We also observed an increase in the plasma concentrations of total homocysteine and methylmalonic acid (MMA), two functional indicators of vitamin B12 status, with increase in plasma folate under low vitamin B12 status. These data strongly imply that high plasma folate is associated with the exacerbation of both the biochemical and clinical status of vitamin B12 deficiency. Hence any food fortification policy that includes folic acid should also include vitamin B12. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Isovalerianeacidæmi--en sjælden og alvorlig defekt i nedbrydningen af leucin

DEFF Research Database (Denmark)

Lund, Ann-Britt Kiholm; Lund, Allan

2011-01-01

Isovaleric acidaemia (IVA) is an organic acidemia caused by deficient metabolism of the essential amino acid leucine. We describe the biochemistry, diagnostics, and treatment of IVA, and present the known Danish patients.......Isovaleric acidaemia (IVA) is an organic acidemia caused by deficient metabolism of the essential amino acid leucine. We describe the biochemistry, diagnostics, and treatment of IVA, and present the known Danish patients....

Bench-to-bedside review: Treating acid–base abnormalities in the intensive care unit – the role of renal replacement therapy

OpenAIRE

Naka, Toshio; Bellomo, Rinaldo

2004-01-01

Acid–base disorders are common in critically ill patients. Metabolic acid–base disorders are particularly common in patients who require acute renal replacement therapy. In these patients, metabolic acidosis is common and multifactorial in origin. Analysis of acid–base status using the Stewart–Figge methodology shows that these patients have greater acidemia despite the presence of hypoalbuminemic alkalosis. This acidemia is mostly secondary to hyperphosphatemia, hyperlactatemia, and the accu...

Speciation of As(III), As(V), MMA and DMA in contaminated soil extracts by HPLC-ICP/MS

Energy Technology Data Exchange (ETDEWEB)

Bissen, M.; Frimmel, F.H. [Engler-Bunte-Institut, Univ. Karlsruhe (Germany)

2000-05-01

A method to separate and quantify two inorganic arsenic species As(III) and As(V) and two organic arsenic species, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), by HPLC-ICP/MS has been developed. The separation of arsenic species was achieved on the anionic exchange column IonPac {sup trademark} AS11 (Dionex) with NaOH as mobile phase. The technique was successfully applied to analyze extracts of two contaminated soils, sampled at a former tannery site (soil 1) and a former paint production site (soil 2). The soils were extracted at pH values similar to the natural environment. Extractions were performed at different pH values with 0.3 M ammonium oxalate (pH = 3), milli-Q water (pH = 5.8), 0.3 M sodium carbonate (pH = 8) and 0.3 M sodium bicarbonate (pH = 11). No organically bound arsenic was found in the extracts. As(V) was the major component. Only up to 0.04% of the total arsenic contained in soil 1 were mobilized. The highest amount of extracted arsenic was found at the highest pH. In the milli-Q water extract of soil 1 As(III) and As(V) were found. High amounts of As(V) were found in the extracts of soil 2. Up to 20% of the total arsenic bound to soil 2 constituents were released. The results show that the mobilization of arsenic depended on the pH value of the extraction solution and the kind of extracted soil. Dramatic consequences have to be expected for pH changes in the environment especially in cases where soils contain high amounts of mobile arsenic. (orig.)

Geoportale del Consorzio LaMMA Disseminazione di dati meteo in near real-time tramite standard OGC e software Open Source

Directory of Open Access Journals (Sweden)

Simone Giannechini

2014-02-01

Full Text Available This paper describes the spatial data infrastructure (SDI used by the LaMMA Consortium - Environmental Mod elling and Monitoring Laboratory for Sustainable Developm ent of Tuscany Region for sharing, viewing and cataloguing (metadata and related information all geospatial data that are daily proc essed and used op erationally in many meteorological and environmental app lications.The SDI was develop ed using Open Source technologies, mo reover the geospatial data has been imp lemented through protoco ls based on ogc (Open Geospatial Consortium standards such as WMS, WFS and CSW. Geoserver was used for disseminating geospatial data and maps through OGC WMS and WFS protoco ls while GeoNetwork was used as the cataloguing and search po rtal through also the CSW protocol; eventually MapStore was used to implement the mash-up front-end.The innovative aspect of this po rtal is the fact that it currently is ingesting, fusing and disseminating geospatial data related to the MetOcfield from various sources in near real-time in a comp rehensive manner that allows users to create add ed value visualizations for the support of operational use cases as well as to access and download underlying data (where app licable.

Inhibition of enamel demineralization and bond-strength properties of bioactive glass containing 4-META/MMA-TBB-based resin adhesive.

Science.gov (United States)

Kohda, Naohisa; Iijima, Masahiro; Kawaguchi, Kyotaro; Toshima, Hirokazu; Muguruma, Takeshi; Endo, Kazuhiko; Mizoguchi, Itaru

2015-06-01

We investigated the enamel demineralization-prevention ability and shear bond strength (SBS) properties of 4-methacryloxyethyl trimellitic anhydride/methyl methacrylate-tri-n-butyl borane (4-META/MMA-TBB)-based resin containing various amounts (0-50%) of bioactive glass (BG). Disk-shaped specimens were immersed in distilled water and ions released were analysed by inductively coupled plasma atomic-emission spectroscopy. Samples were also immersed in lactic acid solution (pH 4.6) to estimate acid-neutralizing ability. Brackets were bonded to human premolars with BG-containing resins and the bonded teeth were alternately immersed in demineralizing (pH 4.55) and remineralizing (pH 6.8) solutions for 14 d. The enamel hardness was determined by nanoindentation testing at twenty equidistant distances from the external surface. The SBS for each sample was examined. The amounts of ions released [calcium (Ca), sodium (Na), silicon (Si), and boron (B)] and the acid-neutralizing ability increased with increasing BG content. After alternating immersion, the specimens bonded with the BG-containing resin with high BG content were harder than those in the other groups in some locations 1-18.5 μm from the enamel surface. Bioactive glass-containing (10-40%) resin had bond strength equivalent to the control specimen. Thus, the SBS obtained for BG-containing resin (6.5-9.2 MPa) was clinically acceptable, suggesting that this material has the ability to prevent enamel demineralization. © 2015 Eur J Oral Sci.

Clinical importance of the middle meningeal artery: A review of the literature.

Science.gov (United States)

Yu, Jinlu; Guo, Yunbao; Xu, Baofeng; Xu, Kan

2016-01-01

The middle meningeal artery (MMA) is a very important artery in neurosurgery. Many diseases, including dural arteriovenous fistula (DAVF), pseudoaneurysm, true aneurysm, traumatic arteriovenous fistula (AVF), moyamoya disease (MMD), recurrent chronic subdural hematoma (CSDH), migraine and meningioma, can involve the MMA. In these diseases, the lesions occur in either the MMA itself and treatment is necessary, or the MMA is used as the pathway to treat the lesions; therefore, the MMA is very important to the development and treatment of a variety of neurosurgical diseases. However, no systematic review describing the importance of MMA has been published. In this study, we used the PUBMED database to perform a review of the literature on the MMA to increase our understanding of its role in neurosurgery. After performing this review, we found that the MMA was commonly used to access DAVFs and meningiomas. Pseudoaneurysms and true aneurysms in the MMA can be effectively treated via endovascular or surgical removal. In MMD, the MMA plays a very important role in the development of collateral circulation and indirect revascularization. For recurrent CDSHs, after burr hole irrigation and drainage have failed, MMA embolization may be attempted. The MMA can also contribute to the occurrence and treatment of migraines. Because the ophthalmic artery can ectopically originate from the MMA, caution must be taken to avoid causing damage to the MMA during operations.

Clinical importance of the middle meningeal artery: A review of the literature

Science.gov (United States)

Yu, Jinlu; Guo, Yunbao; Xu, Baofeng; Xu, Kan

2016-01-01

The middle meningeal artery (MMA) is a very important artery in neurosurgery. Many diseases, including dural arteriovenous fistula (DAVF), pseudoaneurysm, true aneurysm, traumatic arteriovenous fistula (AVF), moyamoya disease (MMD), recurrent chronic subdural hematoma (CSDH), migraine and meningioma, can involve the MMA. In these diseases, the lesions occur in either the MMA itself and treatment is necessary, or the MMA is used as the pathway to treat the lesions; therefore, the MMA is very important to the development and treatment of a variety of neurosurgical diseases. However, no systematic review describing the importance of MMA has been published. In this study, we used the PUBMED database to perform a review of the literature on the MMA to increase our understanding of its role in neurosurgery. After performing this review, we found that the MMA was commonly used to access DAVFs and meningiomas. Pseudoaneurysms and true aneurysms in the MMA can be effectively treated via endovascular or surgical removal. In MMD, the MMA plays a very important role in the development of collateral circulation and indirect revascularization. For recurrent CDSHs, after burr hole irrigation and drainage have failed, MMA embolization may be attempted. The MMA can also contribute to the occurrence and treatment of migraines. Because the ophthalmic artery can ectopically originate from the MMA, caution must be taken to avoid causing damage to the MMA during operations. PMID:27766029

One-carbon metabolites and telomere length in a prospective and randomized study of B- and/or D-vitamin supplementation.

Science.gov (United States)

Pusceddu, Irene; Herrmann, Markus; Kirsch, Susanne H; Werner, Christian; Hübner, Ulrich; Bodis, Marion; Laufs, Ulrich; Widmann, Thomas; Wagenpfeil, Stefan; Geisel, Jürgen; Herrmann, Wolfgang

2017-08-01

Vitamin B deficiency is common in elderly people and has been associated with an increased risk of developing age-related diseases. B-vitamins are essential for the synthesis and stability of DNA. Telomers are the end caps of chromosomes that shorten progressively with age, and short telomers are associated with DNA instability. In the present randomized intervention study, we investigated whether the one-carbon metabolism is related to telomere length, a surrogate marker for cellular aging. Sixty-five subjects (>54 years) were randomly assigned to receive either a daily combination of vitamin D3 (1200 IU), folic acid (0.5 mg), vitamin B 12 (0.5 mg), vitamin B 6 (50 mg) and calcium carbonate (456 mg) (group A) or vitamin D3 and calcium carbonate alone (group B). Blood testing was performed at baseline and after 1 year of supplementation. The concentrations of several metabolites of the one-carbon pathway, as well as relative telomere length (RTL) and 5,10-methylenetetrahydrofolate reductase C677T genotype, were analyzed. At baseline, age- and gender-adjusted RTL correlated with total folate and 5-methyltetrahydrofolate (5-methylTHF). Subjects with RTL above the median had higher concentrations of total folate and 5-methylTHF compared to subjects below the median. At study end, gender- and age-adjusted RTL correlated in group A with methylmalonic acid (MMA; r = -0.460, p = 0.0012) and choline (r = 0.434, p = 0.0021) and in group B with 5,10-methenyltetrahydrofolate (r = 0.455, p = 0.026) and dimethylglycine (DMG; r = -0.386, p = 0.047). Subjects in the group A with RTL above the median had lower MMA and higher choline compared to subjects below the median. The present pilot study suggests a functional relationship between one-carbon metabolism and telomere length. This conclusion is supported by several correlations that were modified by B-vitamin supplementation. In agreement with our hypothesis, the availability of nucleotides and

Impact of modified graphene and microwave irradiation on thermal stability and degradation mechanism of poly (styrene-co-methyl meth acrylate)

Energy Technology Data Exchange (ETDEWEB)

Zubair, Mukarram [Department of Environmental Engineering, University of Dammam, 31982 Dammam (Saudi Arabia); Shehzad, Farrukh [Department of Chemical Engineering, King Fahd University of Petroleum & Minerals, 31261 Dhahran, Saudi Arabia, (Saudi Arabia); Al-Harthi, Mamdouh A., E-mail: mamdouh@kfupm.edu.sa [Department of Chemical Engineering, King Fahd University of Petroleum & Minerals, 31261 Dhahran, Saudi Arabia, (Saudi Arabia); Center of Research Excellence in Nanotechnology, King Fahd University of Petroleum & Minerals, 31261 Dhahran (Saudi Arabia)

2016-06-10

Highlights: • Modified graphene imparts thermal stability to Poly (styrene-co-methyl methacrylate) [P(st-mma)]. • The thermal stability of P(st-mma) decreased with microwave irradiation. • The thermal stability of P(st-mma)/MG nanocomposites increased with irradiation time up to 10 min and decreased subsequently. • The degradation of P(st-mma) and P(st-mma)/MG is governed by random scission model. - Abstract: Poly (styrene-co-methyl methacrylate) [P(st-mma)] composite containing 0.1 wt% modified graphene (MG) was prepared via melt blending. MG was prepared by oxidation method using nitric acid. The P(st-mma) and P(st-mma)MG composite were irradiated using microwave radiation. The degradation mechanism and thermal stability of the irradiated and un-irradiated samples was analyzed by TGA. P(st-mma)MG showed high thermal stability. The average activation energy of thermal degradation was found to be 200 kJ/mol for P(st-mma), 214 kJ/mol for P(st-mma)MG. The activation energy was highest for 10 min irradiated nanocomposites indicating an improvement in stability. The degradation mechanism was investigated by comparing the master plots constructed using the experimental data with theoretical master plots of various kinetic models. The thermal degradation of P(st-mma) and P(st-mma)MG composite before and after irradiation governs the random scission mechanism. SEM and TEM micrographs showed improved interactions and degradation of composites after 10 min and 20 min irradiation respectively.

CONTROLE DE SI, DOR E REPRESENTAÇÃO FEMININA ENTRE LUTADORES(AS DE MIXED MARTIAL ARTS (MMA

Directory of Open Access Journals (Sweden)

Samuel Oliveira Thomazini

2008-12-01

Full Text Available This papers aims to present results of a seven months ethnographic research in three gyms of Mixed Marcial Arts (MAA, focusing the identity construction of the fighters. Observations and interviews were done, as well as pictures and film takes in traing ans competition were also important. The results suggest the existence of bioidentities processes in sense of selfcontrol and rationalization of pain. The representations of the presence of females is quite ambiguous in this universe of masculinity. La investigación se ocupó de tres gimnasios especializados en Mixed Marcial Arts (MAA, analizando rasgos esenciales de la construcción de las identidades de luchadores y luchadoras. Fueran hecahs durante siete meses observaciones participantes (registradas en diario de campo y entrevistas semi-dirigidas. Fotos y filmages de entrenamientos y competiciones fueran también importantes. Los resultados sugieren la presencia de procesos bioidentitários vinculados al control de si mismo, a la racionalización del dolor y, además, representaciones ambiguas sobre la presencia femenina en este universo que es sobretodo masculino. Trata-se de uma pesquisa realizada em três academias especializadas em Mixed Marcial Arts (MMA. Analisa alguns elementos indispensáveis à forja identitária de lutadores(as desta modalidade. A etnografia durou sete meses, oportunidade para combinar uma observação participante (devidamente registrada no diário de notas com a realização de entrevistas semi-estruturadas com os(as atletas. Fotografias e filmagens dos locais de treinamento e de competição foram recursos metodológicos também úteis. Os resultados indicam a existência de processos bioidentitários vinculados ao controle de si e à racionalização da dor, apontando, além disso, para uma representação ambígua em relação à presença feminina em um universo ainda predominantemente masculino.

Tensile strength of the pullout repair technique for the medial meniscus posterior root tear: a porcine study.

Science.gov (United States)

Fujii, Masataka; Furumatsu, Takayuki; Xue, Haowei; Miyazawa, Shinichi; Kodama, Yuya; Hino, Tomohito; Kamatsuki, Yusuke; Ozaki, Toshifumi

2017-10-01

The purpose of this study was to compare the load-to-failure of different common suturing techniques with a new technique for the medial meniscus posterior root tear (MMPRT). Thirty porcine medial menisci were randomly assigned to three suturing techniques used for transtibial pullout repair of the MMPRT (n = 10 per group). Three different meniscal suture configurations were studied: the two simple suture (TSS) technique, the conventional modified Mason-Allen suture (MMA) technique, and the new MMA technique using the FasT-Fix combined with the Ultrabraid (F-MMA). The ultimate failure load was tested using a tensile testing machine. The MMA and F-MMA groups demonstrated significantly higher failure loads than the TSS group (P = 0.0003 and P = 0.0005, respectively). No significant differences were observed between the MMA and F-MMA groups (P = 0.734). The ultimate failure load was significantly greater in the F-MMA than the TSS group and similar to the conventional MMA technique.

Earth Sciences The geochemistry, tectonic setting and origin of the ...

African Journals Online (AJOL)

A massive melanocratic amphibolite, (MMA) occurs in Ilesha schist belt within a series of muscovite schists and amphibolite gneiss. Though metamorphosed, MMA shows no obvious textural deformation. Actinolite, tremolite, hornblende and boitite constitute the major minerals in MMA. Minor minerals in MMA include calcite, ...

Incidence of Injury in Professional Mixed Martial Arts Competitions

Science.gov (United States)

Bledsoe, Gregory H.; Hsu, Edbert B.; Grabowski, Jurek George; Brill, Justin D.; Li, Guohua

2006-01-01

Mixed Martial Arts (MMA) competitions were introduced in the United States with the first Ultimate Fighting Championship (UFC) in 1993. In 2001, Nevada and New Jersey sanctioned MMA events after requiring a series of rule changes. The purpose of this study was to determine the incidence of injury in professional MMA fighters. Data from all professional MMA events that took place between September 2001 and December 2004 in the state of Nevada were obtained from the Nevada Athletic Commission. Medical and outcome data from events were analyzed based on a pair-matched case-control design. Both conditional and unconditional logistic regression models were used to assess risk factors for injury. A total of 171 MMA matches involving 220 different fighters occurred during the study period. There were a total of 96 injuries to 78 fighters. Of the 171 matches fought, 69 (40.3%) ended with at least one injured fighter. The overall injury rate was 28.6 injuries per 100 fight participations or 12.5 injuries per 100 competitor rounds. Facial laceration was the most common injury accounting for 47.9% of all injuries, followed by hand injury (13.5%), nose injury (10.4%), and eye injury (8.3%). With adjustment for weight and match outcome, older age was associated with significantly increased risk of injury. The most common conclusion to a MMA fight was a technical knockout (TKO) followed by a tap out. The injury rate in MMA competitions is compatible with other combat sports involving striking. The lower knockout rates in MMA compared to boxing may help prevent brain injury in MMA events. Key Points Mixed martial arts (MMA) has changed since the first MMA matches in the United States and now has increased safety regulations and sanctioning. MMA competitions have an overall high rate of injury. There have been no MMA deaths in the United States. The knockout (KO) rate in MMA appears to be lower than the KO rate of boxing matches. MMA must continue to be supervised by properly

Incidence of injury in professional mixed martial arts competitions.

Science.gov (United States)

Bledsoe, Gregory H; Hsu, Edbert B; Grabowski, Jurek George; Brill, Justin D; Li, Guohua

2006-01-01

Mixed Martial Arts (MMA) competitions were introduced in the United States with the first Ultimate Fighting Championship (UFC) in 1993. In 2001, Nevada and New Jersey sanctioned MMA events after requiring a series of rule changes. The purpose of this study was to determine the incidence of injury in professional MMA fighters. Data from all professional MMA events that took place between September 2001 and December 2004 in the state of Nevada were obtained from the Nevada Athletic Commission. Medical and outcome data from events were analyzed based on a pair-matched case-control design. Both conditional and unconditional logistic regression models were used to assess risk factors for injury. A total of 171 MMA matches involving 220 different fighters occurred during the study period. There were a total of 96 injuries to 78 fighters. Of the 171 matches fought, 69 (40.3%) ended with at least one injured fighter. The overall injury rate was 28.6 injuries per 100 fight participations or 12.5 injuries per 100 competitor rounds. Facial laceration was the most common injury accounting for 47.9% of all injuries, followed by hand injury (13.5%), nose injury (10.4%), and eye injury (8.3%). With adjustment for weight and match outcome, older age was associated with significantly increased risk of injury. The most common conclusion to a MMA fight was a technical knockout (TKO) followed by a tap out. The injury rate in MMA competitions is compatible with other combat sports involving striking. The lower knockout rates in MMA compared to boxing may help prevent brain injury in MMA events. Key PointsMixed martial arts (MMA) has changed since the first MMA matches in the United States and now has increased safety regulations and sanctioning.MMA competitions have an overall high rate of injury.There have been no MMA deaths in the United States.The knockout (KO) rate in MMA appears to be lower than the KO rate of boxing matches.MMA must continue to be supervised by properly trained

γ-Glutamylmethylamide Is an Essential Intermediate in the Metabolism of Methylamine by Methylocella silvestris▿

Science.gov (United States)

Chen, Yin; Scanlan, Julie; Song, Lijiang; Crombie, Andrew; Rahman, M. Tanvir; Schäfer, Hendrik; Murrell, J. Colin

2010-01-01

Methylocella silvestris BL2, a facultative methane utilizer, can grow on monomethylamine (MMA) as a sole carbon and nitrogen source. No activity of MMA dehydrogenase was detectable. Instead, this bacterium utilizes a methylated amino acid pathway (γ-glutamylmethylamide [GMA] and N-methylglutamate [NMG]) for MMA metabolism. The activities of the two key enzymes in this pathway, GMA synthetase and NMG dehydrogenase, were found when the bacterium was grown on MMA. GMA was detected by high-performance liquid chromatography-mass spectrometry only when the bacterium was grown on MMA but not when it was grown on methanol. Proteomic analysis of soluble and membrane fractions of the proteome from MMA- and methanol-grown cultures revealed that an eight-gene cluster (Msil2632 to Msil2639) was induced by MMA and cotranscribed as an operon, as shown by reverse transcription-PCR. GMA-dissimilating enzyme activity was also detected when it was grown on MMA. Formaldehyde and ammonium production from GMA was dependent on glutamate but not on α-ketoglutarate. Marker exchange mutagenesis of a putative GMAS gene homologue (gmas, Msil2635) within this eight-gene cluster, with a kanamycin gene cassette, abolished growth of M. silvestris on MMA as either a sole carbon or a sole nitrogen source. Overall, our results suggest that gmas is essential in MMA metabolism by M. silvestris. PMID:20472738

{gamma}-Glutamylmethylamide is an essential intermediate in the metabolism of methylamine by Methylocella silvestris.

Science.gov (United States)

Chen, Yin; Scanlan, Julie; Song, Lijiang; Crombie, Andrew; Rahman, M Tanvir; Schäfer, Hendrik; Murrell, J Colin

2010-07-01

Methylocella silvestris BL2, a facultative methane utilizer, can grow on monomethylamine (MMA) as a sole carbon and nitrogen source. No activity of MMA dehydrogenase was detectable. Instead, this bacterium utilizes a methylated amino acid pathway (gamma-glutamylmethylamide [GMA] and N-methylglutamate [NMG]) for MMA metabolism. The activities of the two key enzymes in this pathway, GMA synthetase and NMG dehydrogenase, were found when the bacterium was grown on MMA. GMA was detected by high-performance liquid chromatography-mass spectrometry only when the bacterium was grown on MMA but not when it was grown on methanol. Proteomic analysis of soluble and membrane fractions of the proteome from MMA- and methanol-grown cultures revealed that an eight-gene cluster (Msil2632 to Msil2639) was induced by MMA and cotranscribed as an operon, as shown by reverse transcription-PCR. GMA-dissimilating enzyme activity was also detected when it was grown on MMA. Formaldehyde and ammonium production from GMA was dependent on glutamate but not on alpha-ketoglutarate. Marker exchange mutagenesis of a putative GMAS gene homologue (gmas, Msil2635) within this eight-gene cluster, with a kanamycin gene cassette, abolished growth of M. silvestris on MMA as either a sole carbon or a sole nitrogen source. Overall, our results suggest that gmas is essential in MMA metabolism by M. silvestris.

Assessment of obstructive sleep apnoea treatment success or failure after maxillomandibular advancement.

Science.gov (United States)

de Ruiter, M H T; Apperloo, R C; Milstein, D M J; de Lange, J

2017-11-01

Maxillomandibular advancement (MMA) is an alternative therapeutic option that is highly effective for treating obstructive sleep apnoea (OSA). MMA provides a solution for OSA patients that have difficulty accepting lifelong treatments with continuous positive airway pressure or mandibular advancement devices. The goal of this study was to investigate the different characteristics that determine OSA treatment success/failure after MMA. The apnoea-hypopnoea index (AHI) was used to determine the success or failure of OSA treatment after MMA. Sixty-two patients underwent MMA for moderate and severe OSA. A 71% success rate was observed with a mean AHI reduction of 69%. A statistically significant larger neck circumference was measured in patients with failed OSA treatments following MMA (P=0.008), and older patients had failed OSA treatments with MMA: 58 vs. 53 years respectively (P=0.037). Cephalometric analysis revealed no differences between successful and failed OSA treatment outcomes. There was no difference in maxillary and mandibular advancements between success and failed MMA-treated OSA patients. The complications most frequently reported following MMA were sensory disturbances in the inferior alveolar nerve (60%) and malocclusion (24%). The results suggest that age and neck girth may be important factors that could predict susceptibility to OSA treatment failures by MMA. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

The Influence of Gestational Age on the Loss of Maternal Measles ...

African Journals Online (AJOL)

Background: Maternal measles antibodies (MMA) are actively transferred in mother-infant pairs during third trimester of pregnancy. Gestational age (GA) affects the levels of MMA such that longer GA may result in infants starting out with high levels of MMA. Objective: To determine the influence of GA on the loss of MMA in ...

Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

Energy Technology Data Exchange (ETDEWEB)

Guo, Lei [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Xiao, Yongsheng [Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States); Wang, Yinsheng, E-mail: yinsheng.wang@ucr.edu [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States)

2014-05-15

Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ∼ 6500 unique proteins quantified, ∼ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content. - Highlights: • MMA(III)-induced perturbation of the entire proteome of GM00637 cells is studied. • Quantitative proteomic approach revealed alterations of multiple cellular pathways. • MMA(III) inhibits de novo cholesterol biosynthesis. • MMA

Urinary arsenic metabolism in a Western Chinese population exposed to high-dose inorganic arsenic in drinking water: Influence of ethnicity and genetic polymorphisms

International Nuclear Information System (INIS)

Fu, Songbo; Wu, Jie; Li, Yuanyuan; Liu, Yan; Gao, Yanhui; Yao, Feifei; Qiu, Chuanying; Song, Li; Wu, Yu; Liao, Yongjian; Sun, Dianjun

2014-01-01

To investigate the differences in urinary arsenic metabolism patterns of individuals exposed to a high concentration of inorganic arsenic (iAs) in drinking water, an epidemiological investigation was conducted with 155 individuals living in a village where the arsenic concentration in the drinking water was 969 μg/L. Blood and urine samples were collected from 66 individuals including 51 cases with skin lesions and 15 controls without skin lesions. The results showed that monomethylated arsenic (MMA), the percentage of MMA (%MMA) and the ratio of MMA to iAs (MMA/iAs) were significantly increased in patients with skin lesions as compared to controls, while dimethylated arsenic (DMA), the percentage of DMA (%DMA) and the ratio of DMA to MMA (DMA/MMA) were significantly reduced. The percent DMA of individuals with the Ala/Asp genotype of glutathione S-transferase omega 1 (GSTO1) was significantly lower than those with Ala/Ala. The percent MMA of individuals with the A2B/A2B genotype of arsenic (+ 3 oxidation state) methyltransferase (AS3MT) was significantly lower than those with AB/A2B. The iAs and total arsenic (tAs) content in the urine of a Tibetan population were significantly higher than that of Han and Hui ethnicities, whereas MMA/iAs was significantly lower than that of Han and Hui ethnicities. Our results showed that when exposed to the same arsenic environment, different individuals exhibited different urinary arsenic metabolism patterns. Gender and ethnicity affect these differences and above polymorphisms may be effectors too. - Highlights: • We first survey a village with high iAs content in the drinking water (969 μg/L). • 90 villagers suffered typical skin lesions with a morbidity rate of 58%. • Cases exhibited higher %MMA and MMA/iAs, and lower %DMA and DMA/MMA than controls. • Gender and ethnicity affect the differences of iAs methylation metabolism levels. • GSTO1 and AS3MT gene polymorphisms may be factors too

Urinary arsenic metabolism in a Western Chinese population exposed to high-dose inorganic arsenic in drinking water: Influence of ethnicity and genetic polymorphisms

Energy Technology Data Exchange (ETDEWEB)

Fu, Songbo [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China); Wu, Jie [Laboratory of Medical Genetics, Harbin Medical University, Harbin 150081 (China); Li, Yuanyuan [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China); Liu, Yan [Department of Health Statistics, Harbin Medical University, Harbin 150081 (China); Gao, Yanhui; Yao, Feifei [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China); Qiu, Chuanying [Dongcheng District Center for Disease Control and Prevention, Beijing 100009 (China); Song, Li; Wu, Yu [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China); Liao, Yongjian [Gansu Center for Disease Control and Prevention, 730020 (China); Sun, Dianjun, E-mail: hrbmusdj@163.com [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China)

2014-01-01

To investigate the differences in urinary arsenic metabolism patterns of individuals exposed to a high concentration of inorganic arsenic (iAs) in drinking water, an epidemiological investigation was conducted with 155 individuals living in a village where the arsenic concentration in the drinking water was 969 μg/L. Blood and urine samples were collected from 66 individuals including 51 cases with skin lesions and 15 controls without skin lesions. The results showed that monomethylated arsenic (MMA), the percentage of MMA (%MMA) and the ratio of MMA to iAs (MMA/iAs) were significantly increased in patients with skin lesions as compared to controls, while dimethylated arsenic (DMA), the percentage of DMA (%DMA) and the ratio of DMA to MMA (DMA/MMA) were significantly reduced. The percent DMA of individuals with the Ala/Asp genotype of glutathione S-transferase omega 1 (GSTO1) was significantly lower than those with Ala/Ala. The percent MMA of individuals with the A2B/A2B genotype of arsenic (+ 3 oxidation state) methyltransferase (AS3MT) was significantly lower than those with AB/A2B. The iAs and total arsenic (tAs) content in the urine of a Tibetan population were significantly higher than that of Han and Hui ethnicities, whereas MMA/iAs was significantly lower than that of Han and Hui ethnicities. Our results showed that when exposed to the same arsenic environment, different individuals exhibited different urinary arsenic metabolism patterns. Gender and ethnicity affect these differences and above polymorphisms may be effectors too. - Highlights: • We first survey a village with high iAs content in the drinking water (969 μg/L). • 90 villagers suffered typical skin lesions with a morbidity rate of 58%. • Cases exhibited higher %MMA and MMA/iAs, and lower %DMA and DMA/MMA than controls. • Gender and ethnicity affect the differences of iAs methylation metabolism levels. • GSTO1 and AS3MT gene polymorphisms may be factors too.

Physicochemical properties of poly(lactic acid-co-glycolic acid film modified via blending with poly(butyl acrylate-co-methyl methacrylate

Directory of Open Access Journals (Sweden)

Guoquan Zhu

2013-01-01

Full Text Available A series of poly(lactic acid-co-glycolic acid (PLGA/poly(butyl acrylate-co-methyl methacrylate (P(BA-co-MMA blend films with different P(BA-co-MMA mole contents were prepared by casting the polymer blend solution in chloroform. Surface morphologies of the PLGAP(BA-co-MMA blend films were studied by scanning electron microscopy (SEM. Thermal, mechanical, and chemical properties of PLGAP(BA-co-MMA blend films were investigated by differential scanning calorimeter (DSC, thermogravimetric analysis (TGA, tensile tests, and surface contact angle tests. The introduction of P(BA-co-MMA could modify the properties of PLGA films.

聚合物微球固载的N-羟基邻苯二甲酰亚胺在分子氧氧化苯甲醇反应过程中的催化特性%Catalytic characteristics of N-hydroxyphthalimide immobilized on polymer microspheres in oxidation of benzyl alcohol by molecular oxygen

Institute of Scientific and Technical Information of China (English)

杨晓林; 黄建龙; 高保娇; 门吉英

2015-01-01

以甲基丙烯酸缩水甘油酯(GMA)和甲基丙烯酸甲酯(MMA)的交联共聚微球 GMA/MMA 为基质，经过几步大分子反应在微球表面合成与固载了 N-羟基邻苯二甲酰亚胺(NHPI)，形成固载有 NHPI 的聚合物微球GMA/MMA-NHPI。将 GMA/MMA-NHPI 与 Co(OAc)2组成共催化体系，用于分子氧氧化苯甲醇的反应过程。研究结果表明，GMA/MMA-NHPI与Co(OAc)2所构成的共催化体系在温和条件（65℃和常压氧气）下可有效地实现苯甲醇的分子氧氧化过程，将其深度氧化为苯甲酸，显示出较好的催化活性和高的选择性(苯甲酸的选择性为96%)。主催化剂GMA/MMA-NHPI固载的NHPI与助催化剂Co(OAc)2适宜的摩尔比为20：1；主催化剂所含NHPI的摩尔分数为底物的10%时催化剂的用量比较适宜。固体催化剂GMA/MMA-NHPI还具有良好的再循环使用性能。%Crosslinked polymeric microspheres GMA/MMA of glycidyl methacrylate (GMA) and methyl methacrylate (MMA) were prepared, and then N-hydroxyphthalimide (NHPI) was synthesized and immobilized on GMA/MMA microspheres through several polymer reaction steps, resulting in the functionalized microspheres GMA/MMA-NHPI. The solid catalyst GMA/MMA-NHPI in combination with Co(OAc)2 was used in aerobic oxidation of benzyl alcohol. Experimental results showed that the composite catalyst consisting of GMA/MMA-NHPI and Co(OAc)2 could effectively catalyze aerobic oxidation of benzyl alcohol by molecular oxygen under mild conditions (65℃ and normal pressure). Benzyl alcohol was deeply oxidized to benzoic acid. Although benzyl alcohol conversion rate was not very high, catalytic activity was satisfactory and benzoic acid selectivity was as high as 96%. The appropriate molar ratio of immobilized NHPI on GMA/MMA-NHPI microspheres to Co(OAc)2 was 20:1, and the appropriate amount of GMA/MMA-NHPI was 10% (mol) of the substrate. The solid catalyst GMA/MMA-NHPI microspheres showed good recycling and reusing

Congenital genetic inborn errors of metabolism presenting as an adult or persisting into adulthood: neuroimaging in the more common or recognizable disorders.

Science.gov (United States)

Krishna, Shri H; McKinney, Alexander M; Lucato, Leandro T

2014-04-01

Numerous congenital-genetic inborn errors of metabolism (CIEMs) have been identified and characterized in detail within recent decades, with promising therapeutic options. Neuroimaging is becoming increasingly utilized in earlier stages of CIEMs, and even in asymptomatic relatives of patients with a CIEM, so as to monitor disease progress and treatment response. This review attempts to summarize in a concise fashion the neuroimaging findings of various CIEMs that may present in adulthood, as well as those that may persist into adulthood, whether because of beneficial therapy or a delay in diagnosis. Notably, some of these disorders have neuroimaging findings that differ from their classic infantile or early childhood forms, whereas others are identical to their early pediatric forms. The focus of this review is their appearance on routine magnetic resonance imaging sequences, with some basic attention to the findings of such CIEMs on specialized neuroimaging, based on recent or preliminary research. The general classes of disorders covered in this complex review are: peroxisomal disorders (adrenoleukodystrophy), lysosomal storage disorders (including metachromatic leukodystrophy, Krabbe or globoid cell leukodystrophy, Fabry, Niemann-Pick, GM1, GM2, Gaucher, mucopolysaccharidoses, and Salla diseases), mitochondrial disorders (including mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes, myoclonic epilepsy with ragged red fibers, Leigh disease, and Kearns-Sayre syndrome), urea cycle disorders, several organic acidemias (including phenylketonuria, maple syrup urine disease, 3-hydroxy-3-methylglutaryl colyase deficiency, glutaric acidurias, methylmalonic academia, proprionic academia, 3-methylglucatonic aciduria, and 2-hydroxyglutaric acidurias), cytoskeletal or transporter molecule defects (including Alexander or fibrinoid leukodystrophy, proteolipid protein-1 defect or Pelizaeus Merzbacher, Wilson, and Huntington diseases), and several

A biological indicator of inorganic arsenic exposure using the sum of urinary inorganic arsenic and monomethylarsonic acid concentrations

Science.gov (United States)

Hata, Akihisa; Kurosawa, Hidetoshi; Endo, Yoko; Yamanaka, Kenzo; Fujitani, Noboru; Endo, Ginji

2016-01-01

Objectives: The sum of urinary inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) concentrations is used for the biological monitoring of occupational iAs exposure. Although DMA is a major metabolite of iAs, it is an inadequate index because high DMA levels are present in urine after seafood consumption. We estimated the urinary iAs+MMA concentration corresponding to iAs exposure. Methods: We used data from two arsenic speciation analyses of urine samples from 330 Bangladeshi with oral iAs exposure and 172 Japanese workers without occupational iAs exposure using high-performance liquid chromatography with inductively coupled plasma mass spectrometry. Results: iAs, MMA, and DMA, but not arsenobetaine (AsBe), were detected in the urine of the Bangladeshi subjects. The correlation between iAs+MMA+DMA and iAs+MMA was obtained as log (iAs+MMA) = 1.038 log (iAs+MMA+DMA) -0.658. Using the regression formula, the iAs+MMA value was calculated as 2.15 and 7.5 μg As/l, corresponding to 3 and 10 μg As/m3 of exposures, respectively. In the urine of the Japanese workers, arsenic was mostly excreted as AsBe. We used the 95th percentile of iAs+MMA (12.6 μg As/l) as the background value. The sum of the calculated and background values can be used as a biological indicator of iAs exposure. Conclusion: We propose 14.8 and 20.1 μg As/l of urinary iAs+MMA as the biological indicators of 3 and 10 μg As/m3 iAs exposure, respectively. PMID:27010090

Influence of CO2 on ultrasound-induced polymerizations in high-pressure fluids

NARCIS (Netherlands)

Kuijpers, M.W.A.; Jacobs, L.J.M.; Kemmere, M.F.; Keurentjes, J.T.F.

2005-01-01

A strong viscosity increase upon polymerization hinders cavitation and subsequent radical formation during an ultrasound-induced bulk polymerization. Ultrasound-induced radical polymerizations of methyl methacrylate (MMA) have been performed in CO2-expanded MMA, as well as in bulk MMA. For this

Arsenite and monomethylarsonous acid generate oxidative stress response in human bladder cell culture

International Nuclear Information System (INIS)

Eblin, K.E.; Bowen, M.E.; Cromey, D.W.; Bredfeldt, T.G.; Mash, E.A.; Lau, S.S.; Gandolfi, A.J.

2006-01-01

Arsenicals have commonly been seen to induce reactive oxygen species (ROS) which can lead to DNA damage and oxidative stress. At low levels, arsenicals still induce the formation of ROS, leading to DNA damage and protein alterations. UROtsa cells, an immortalized human urothelial cell line, were used to study the effects of arsenicals on the human bladder, a site of arsenical bioconcentration and carcinogenesis. Biotransformation of As(III) by UROtsa cells has been shown to produce methylated species, namely monomethylarsonous acid [MMA(III)], which has been shown to be 20 times more cytotoxic. Confocal fluorescence images of UROtsa cells treated with arsenicals and the ROS sensing probe, DCFDA, showed an increase of intracellular ROS within five min after 1 μM and 10 μM As(III) treatments. In contrast, 50 and 500 nM MMA(III) required pretreatment for 30 min before inducing ROS. The increase in ROS was ameliorated by preincubation with either SOD or catalase. An interesting aspect of these ROS detection studies is the noticeable difference between concentrations of As(III) and MMA(III) used, further supporting the increased cytotoxicity of MMA(III), as well as the increased amount of time required for MMA(III) to cause oxidative stress. These arsenical-induced ROS produced oxidative DNA damage as evidenced by an increase in 8-hydroxyl-2'-deoxyguanosine (8-oxo-dG) with either 50 nM or 5 μM MMA(III) exposure. These findings provide support that MMA(III) cause a genotoxic response upon generation of ROS. Both As(III) and MMA(III) were also able to induce Hsp70 and MT protein levels above control, showing that the cells recognize the ROS and respond. As(III) rapidly induces the formation of ROS, possibly through it oxidation to As(V) and further metabolism to MMA(III)/(V). These studies provide evidence for a different mechanism of MMA(III) toxicity, one that MMA(III) first interacts with cellular components before an ROS response is generated, taking longer to

Persistence of DNA damage following exposure of human bladder cells to chronic monomethylarsonous acid

International Nuclear Information System (INIS)

Wnek, S.M.; Medeiros, M.K.; Eblin, K.E.; Gandolfi, A.J.

2009-01-01

Malignant transformation was demonstrated in UROtsa cells following 52-weeks of exposure to 50 nM monomethylarsonous acid (MMA III ); the result was the malignantly transformed cell line, URO-MSC. URO-MSC cells were used to study the induction of DNA damage and the alteration of DNA repair enzymes in both the presence of MMA III [URO-MSC(+)] and after subsequent removal of MMA III [URO-MSC(-)] following chronic, low-level exposure. In the presence of MMA III , URO-MSC(+) cells demonstrated a sustained increase in DNA damage following 12-weeks of exposure; in particular, a significant increase in DNA single-strand breaks at 12-weeks of exposure consistently elevated through 52 weeks. The persistence of DNA damage in URO-MSC cells was assessed after a 2-week removal of MMA III . URO-MSC(-) cells demonstrated a decrease in DNA damage compared to URO-MSC(+); however, DNA damage in URO-MSC(-) remained significantly elevated when compared to untreated UROtsa and increased in a time-dependent manner. Reactive oxygen species (ROS) were demonstrated to be a critical component in the generation of DNA damage determined through the incubation of ROS scavengers with URO-MSC cells. Poly (ADP-ribose) polymerase (PARP) is a key repair enzyme in DNA single-strand break repair. URO-MSC(+) resulted in a slight increase in PARP activity after 36-weeks of MMA III exposure, suggesting the presence of MMA III is inhibiting the increase in PARP activity. In support, PARP activity in URO-MSC(-) increased significantly, coinciding with a subsequent decrease in DNA damage demonstrated in URO-MSC(-) compared to URO-MSC(+). These data demonstrate that chronic, low-level exposure of UROtsa cells to 50 nM MMA III results in: the induction of DNA damage that remains elevated upon removal of MMA III ; increased levels of ROS that play a role in MMA III induced-DNA damage; and decreased PARP activity in the presence of MMA III .

疏水改性阳离子高分子絮凝剂的合成及其絮凝性能%Synthesis of the hydrophobic, modified, cationic, and polymeric flocculant and its flocculation capacity for wastewater

Institute of Scientific and Technical Information of China (English)

王永军; 吕学良; 郭海军

2017-01-01

Hydrophobic,modified,cationic,and polymeric flocculant P (DMC-MMA)has been polymerized and prepared by soap-free emulsion polymerization,using methacryloxyethyltrimethyl ammonium chloride (DMC) and methyl methacrylate (MMA)as raw materials.The influences of different factors,including monomer mass fraction,reaction temperature,initiator dosage and reaction time on the P (DMC-MMA)removing effect are investigated.The results show that under the following conditions:total monomer mass fraction is 30％,n (DMC):n (MMA)=7:3,reaction temperature 75 ℃,initiator dosage 0.5％ and reaction time 8 h,the prepared P(DMC-MMA)has good flocculation effect.The maximum oil removing rate can reach 96％.In addition,the flocs do not adhere to the walls.%以甲基丙烯酰氧乙基三甲基氯化铵(DMC)和甲基丙烯酸甲酯(MMA)为原料,通过无皂乳液聚合制备了流动性好的疏水改性阳离子型高分子絮凝剂P (DMC-MMA),并考察了不同因素对P(DMC-MMA)除油效果的影响.结果表明:在单体总质量分数为30％、n(DMC):n(MMA)=7:3、反应温度75℃、引发剂用量为0.5％、反应时间8h条件下制备的P(DMC-MMA)具有良好的絮凝效果,最高除油率可达96％,且絮体不黏壁.

The effects of maternal haemoglobin as an indicator of maternal ...

African Journals Online (AJOL)

Background: Maternal measles antibodies (MMA) are actively transferred through the placenta from mother to foetus. A relationship could exist between MMA of mother-infant pairs and maternal nutritional indicator (haemoglobin). Objectives: This study reviewed the effects of maternal haemoglobin (Hb) on MMA of ...

Synergistic effect of functionally active methacrylate polymer and ZnO nanoparticles on optical and dielectric properties

International Nuclear Information System (INIS)

Ilangovan, Pugazhenthi; Sakvai, Mohammed Safiullah; Kottur, Anver Basha

2017-01-01

A crucial need to design a functionally active polymer hybrid for the protection of material structure that are exposing to harmful Ultra Violet radiation (UV). In this paper a poly(pyridine-4-yl-methyl) methacrylate ZnO nanocomposite (PPyMMA/ZnO) was developed by in-situ solution polymerization. The X-ray diffraction (XRD) studies confirmed that the nanocomposite is homogeneous with good compatibility between the two counterparts. The morphological variation arises owing to the incorporation of OA-ZnO in the PPyMMA were observed by using electron microscope techniques. The thermal behaviour of PPyMMA and its ZnO nanocomposites were analysed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The dielectric properties of the polymer and its ZnO nanocomposites were studied over a wide range of temperature (30–300 °C) at frequency 100 KHz. An optical study was carried out to test the optical properties of PPyMMA/ZnO (2, 5 and 5%), which reveals that 2% ZnONPs loading exhibits an excellent UV shielding properties. - Highlights: • The PPyMMA/ZnO was prepared by in-situ solution polymerization. • The OA-ZnO were incorporated during the solution polymerization of PPyMMA. • The PPyMMA/ZnO nanocomposite exhibit an improved dielectric property. • The PPyMMA with OA-ZnO nanocomposite show an excellent UV-shielding.

Synergistic effect of functionally active methacrylate polymer and ZnO nanoparticles on optical and dielectric properties

Energy Technology Data Exchange (ETDEWEB)

Ilangovan, Pugazhenthi; Sakvai, Mohammed Safiullah; Kottur, Anver Basha, E-mail: kanverbasha@gmail.com

2017-06-01

A crucial need to design a functionally active polymer hybrid for the protection of material structure that are exposing to harmful Ultra Violet radiation (UV). In this paper a poly(pyridine-4-yl-methyl) methacrylate ZnO nanocomposite (PPyMMA/ZnO) was developed by in-situ solution polymerization. The X-ray diffraction (XRD) studies confirmed that the nanocomposite is homogeneous with good compatibility between the two counterparts. The morphological variation arises owing to the incorporation of OA-ZnO in the PPyMMA were observed by using electron microscope techniques. The thermal behaviour of PPyMMA and its ZnO nanocomposites were analysed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The dielectric properties of the polymer and its ZnO nanocomposites were studied over a wide range of temperature (30–300 °C) at frequency 100 KHz. An optical study was carried out to test the optical properties of PPyMMA/ZnO (2, 5 and 5%), which reveals that 2% ZnONPs loading exhibits an excellent UV shielding properties. - Highlights: • The PPyMMA/ZnO was prepared by in-situ solution polymerization. • The OA-ZnO were incorporated during the solution polymerization of PPyMMA. • The PPyMMA/ZnO nanocomposite exhibit an improved dielectric property. • The PPyMMA with OA-ZnO nanocomposite show an excellent UV-shielding.

Interrater agreement of an observational tool to code knockouts and technical knockouts in mixed martial arts.

Science.gov (United States)

Lawrence, David W; Hutchison, Michael G; Cusimano, Michael D; Singh, Tanveer; Li, Luke

2014-09-01

Interrater agreement evaluation of a tool to document and code the situational factors and mechanisms of knockouts (KOs) and technical knockouts (TKOs) in mixed martial arts (MMA). Retrospective case series. Professional MMA matches from the Ultimate Fighting Championship-2006-2012. Two nonmedically trained independent raters. The MMA Knockout Tool (MMA-KT) consists of 20 factors and captures and codes information on match characteristics, situational context preceding KOs and TKOs, as well as describing competitor states during these outcomes. The MMA-KT also evaluates the mechanism of action and subsequent events surrounding a KO. The 2 raters coded 125 unique events for a total of 250 events. The 8 factors of Part A had an average κ of 0.87 (SD = 0.10; range = 0.65-0.98); 7 were considered "substantial" agreement and 1 "moderate." Part B consists of 12 factors with an average κ of 0.84 (SD = 0.16; range = 0.59-1.0); 7 classified as "substantial" agreement, 4 "moderate," and 1 "fair." The majority of the factors in the MMA-KT demonstrated substantial interrater agreement, with an average κ of 0.86 (SD = 0.13; range = 0.59-1.0). The MMA-KT is a reliable tool to extract and code relevant information to investigate the situational factors and mechanism of KOs and TKOs in MMA competitions.

Genetics Home Reference: propionic acidemia

Science.gov (United States)

... Cerdá C, Scholl-Bürgi S, Skovby F, Wijburg F, MacDonald A, Martinelli D, Sass JO, Valayannopoulos V, Chakrapani ... Cerdá C, Scholl-Bürgi S, Skovby F, Wijburg F, MacDonald A, Martinelli D, Sass JO, Valayannopoulos V, Chakrapani ...

INCIDENCE OF INJURY IN PROFESSIONAL MIXED MARTIAL ARTS COMPETITIONS

Directory of Open Access Journals (Sweden)

Gregory H. Bledsoe

2006-07-01

Full Text Available Mixed Martial Arts (MMA competitions were introduced in the United States with the first Ultimate Fighting Championship (UFC in 1993. In 2001, Nevada and New Jersey sanctioned MMA events after requiring a series of rule changes. The purpose of this study was to determine the incidence of injury in professional MMA fighters. Data from all professional MMA events that took place between September 2001 and December 2004 in the state of Nevada were obtained from the Nevada Athletic Commission. Medical and outcome data from events were analyzed based on a pair-matched case-control design. Both conditional and unconditional logistic regression models were used to assess risk factors for injury. A total of 171 MMA matches involving 220 different fighters occurred during the study period. There were a total of 96 injuries to 78 fighters. Of the 171 matches fought, 69 (40.3% ended with at least one injured fighter. The overall injury rate was 28.6 injuries per 100 fight participations or 12.5 injuries per 100 competitor rounds. Facial laceration was the most common injury accounting for 47.9% of all injuries, followed by hand injury (13.5%, nose injury (10.4%, and eye injury (8.3%. With adjustment for weight and match outcome, older age was associated with significantly increased risk of injury. The most common conclusion to a MMA fight was a technical knockout (TKO followed by a tap out. The injury rate in MMA competitions is compatible with other combat sports involving striking. The lower knockout rates in MMA compared to boxing may help prevent brain injury in MMA events

[Intrapartum amnioinfusion in patients with meconium-stained amniotic fluid].

Science.gov (United States)

Engel, Karina; Samborska, Monika; Bilar, Marek; Sipak-Szmigiel, Olimpia; Ronin-Walknowska, Elzbieta

2008-09-01

The aim of the study was to evaluate the effect of intrapartum amnioinfusion in the presence of meconium stained amniotic fluid. 93 women with meconium-stained amniotic fluid were assigned to receive amnioinfusion or no amnioinfusion (128 women). The trials were evaluated for fetal distress syndrome, route of delivery, fetal acidemia, Apgar score at 1 and 5 min., meconium aspiration syndrome, postpartum endometritis and maternal hospital stays. Amnioinfusion in cases of meconium-stained fluid did not improve the number of fetal distress symptoms during fetal heart rate monitoring. Amnioinfusion was associated with a significant decrease of neonatal acidemia although it did not improve Apgar score. In our study amnioinfusion was not associated with reduction in the incidence of neonatal outcome and puerperial complications.

Altered ion transport in normal human bronchial epithelial cells following exposure to chemically distinct metal welding fume particles

Energy Technology Data Exchange (ETDEWEB)

Fedan, Jeffrey S., E-mail: jsf2@cdc.gov; Thompson, Janet A.; Meighan, Terence G.; Zeidler-Erdely, Patti C.; Antonini, James M.

2017-07-01

Welding fume inhalation causes pulmonary toxicity, including susceptibility to infection. We hypothesized that airway epithelial ion transport is a target of fume toxicity, and investigated the effects of fume particulates from manual metal arc-stainless steel (MMA-SS) and gas metal arc-mild steel (GMA-MS) on ion transport in normal human bronchial epithelium (NHBE) cultured in air-interface. MMA-SS particles, more soluble than GMA-MS particles, contain Cr, Ni, Fe and Mn; GMA-MS particles contain Fe and Mn. MMA-SS or GMA-MS particles (0.0167–166.7 μg/cm{sup 2}) were applied apically to NHBEs. After 18 h transepithelial potential difference (V{sub t}), resistance (R{sub t}), and short circuit current (I{sub sc}) were measured. Particle effects on Na{sup +} and Cl¯ channels and the Na{sup +},K{sup +},2Cl¯-cotransporter were evaluated using amiloride (apical), 5-nitro-2-[(3-phenylpropyl)amino]benzoic acid (NPPB, apical), and bumetanide (basolateral), respectively. MMA-SS (0.0167–16.7 μg/cm{sup 2}) increased basal V{sub t}. Only 16.7 μg/cm{sup 2} GMA-MS increased basal V{sub t} significantly. MMA-SS or GMA-MS exposure potentiated I{sub sc} responses (decreases) to amiloride and bumetanide, while not affecting those to NPPB, GMA-MS to a lesser degree than MMA-SS. Variable effects on R{sub t} were observed in response to amiloride, and bumetanide. Generally, MMA-SS was more potent in altering responses to amiloride and bumetanide than GMA-MS. Hyperpolarization occurred in the absence of LDH release, but decreases in V{sub t}, R{sub t}, and I{sub sc} at higher fume particulate doses accompanied LDH release, to a greater extent for MMA-SS. Thus, Na{sup +} transport and Na{sup +},K{sup +},2Cl¯-cotransport are affected by fume exposure; MMA-MS is more potent than GMA-MS. Enhanced Na{sup +} absorption and decreased airway surface liquid could compromise defenses against infection. - Highlights: • Welding fume particle toxicity was investigated in human bronchial

76 FR 59129 - Agency Information Collection Request; 30-Day Public Comment Request

Science.gov (United States)

2011-09-23

... Medicare Prescription Drug, Improvement, and Modernization Act (MMA) of 2003 (Pub. L. 108-173) and became operational on July 1, 2005. The MMA legislation and implementing regulations issued on March 8, 2007 instituted a number of changes in the appeals process. The MMA legislation also directed the U.S. Department...

Sweat loss prediction using a multi-model approach.

Science.gov (United States)

Xu, Xiaojiang; Santee, William R

2011-07-01

A new multi-model approach (MMA) for sweat loss prediction is proposed to improve prediction accuracy. MMA was computed as the average of sweat loss predicted by two existing thermoregulation models: i.e., the rational model SCENARIO and the empirical model Heat Strain Decision Aid (HSDA). Three independent physiological datasets, a total of 44 trials, were used to compare predictions by MMA, SCENARIO, and HSDA. The observed sweat losses were collected under different combinations of uniform ensembles, environmental conditions (15-40°C, RH 25-75%), and exercise intensities (250-600 W). Root mean square deviation (RMSD), residual plots, and paired t tests were used to compare predictions with observations. Overall, MMA reduced RMSD by 30-39% in comparison with either SCENARIO or HSDA, and increased the prediction accuracy to 66% from 34% or 55%. Of the MMA predictions, 70% fell within the range of mean observed value ± SD, while only 43% of SCENARIO and 50% of HSDA predictions fell within the same range. Paired t tests showed that differences between observations and MMA predictions were not significant, but differences between observations and SCENARIO or HSDA predictions were significantly different for two datasets. Thus, MMA predicted sweat loss more accurately than either of the two single models for the three datasets used. Future work will be to evaluate MMA using additional physiological data to expand the scope of populations and conditions.

Problem solving based learning model with multiple representations to improve student's mental modelling ability on physics

Science.gov (United States)

Haili, Hasnawati; Maknun, Johar; Siahaan, Parsaoran

2017-08-01

Physics is a lessons that related to students' daily experience. Therefore, before the students studying in class formally, actually they have already have a visualization and prior knowledge about natural phenomenon and could wide it themselves. The learning process in class should be aimed to detect, process, construct, and use students' mental model. So, students' mental model agree with and builds in the right concept. The previous study held in MAN 1 Muna informs that in learning process the teacher did not pay attention students' mental model. As a consequence, the learning process has not tried to build students' mental modelling ability (MMA). The purpose of this study is to describe the improvement of students' MMA as a effect of problem solving based learning model with multiple representations approach. This study is pre experimental design with one group pre post. It is conducted in XI IPA MAN 1 Muna 2016/2017. Data collection uses problem solving test concept the kinetic theory of gasses and interview to get students' MMA. The result of this study is clarification students' MMA which is categorized in 3 category; High Mental Modelling Ability (H-MMA) for 7Mental Modelling Ability (M-MMA) for 3Mental Modelling Ability (L-MMA) for 0 ≤ x ≤ 3 score. The result shows that problem solving based learning model with multiple representations approach can be an alternative to be applied in improving students' MMA.

Epidemiology of mixed martial arts and youth violence in an ethnically diverse sample.

Science.gov (United States)

Hishinuma, Earl S; Umemoto, Karen N; Nguyen, Toan Gia; Chang, Janice Y; Bautista, Randy Paul M

2012-01-01

Mixed martial arts' (MMAs) growing international popularity has rekindled the discussion on the advantages (e.g., exercise) and disadvantages (e.g., possible injury) of contact sports. This study was the first of its kind to examine the psychosocial aspects of MMA and youth violence using an epidemiologic approach with an Asian American and Pacific Islander (AAPI) adolescent sample (N = 881). The results were consistent with the increased popularity of MMA with 52% (adolescent males = 73%, adolescent females = 39%) enjoying watching MMA and 24% (adolescent males = 39%, adolescent females = 13%) practicing professional fight moves with friends. Although statistically significant ethnic differences were found for the two MMA items on a bivariate level, these findings were not statistically significant when considering other variables in the model. The bivariate results revealed a cluster of risk-protective factors. Regarding the multiple regression findings, although enjoying watching MMA remained associated with positive attitudes toward violence and practicing fight moves remained associated with negative out-group orientation, the MMA items were not associated with unique variances of youth violence perpetration and victimization. Implications included the need for further research that includes other diverse samples, more comprehensive and objective MMA and violence measures, and observational and intervention longitudinal studies.

FEM correlation and shock analysis of a VNC MEMS mirror segment

Science.gov (United States)

Aguayo, Eduardo J.; Lyon, Richard; Helmbrecht, Michael; Khomusi, Sausan

2014-08-01

Microelectromechanical systems (MEMS) are becoming more prevalent in today's advanced space technologies. The Visible Nulling Coronagraph (VNC) instrument, being developed at the NASA Goddard Space Flight Center, uses a MEMS Mirror to correct wavefront errors. This MEMS Mirror, the Multiple Mirror Array (MMA), is a key component that will enable the VNC instrument to detect Jupiter and ultimately Earth size exoplanets. Like other MEMS devices, the MMA faces several challenges associated with spaceflight. Therefore, Finite Element Analysis (FEA) is being used to predict the behavior of a single MMA segment under different spaceflight-related environments. Finite Element Analysis results are used to guide the MMA design and ensure its survival during launch and mission operations. A Finite Element Model (FEM) has been developed of the MMA using COMSOL. This model has been correlated to static loading on test specimens. The correlation was performed in several steps—simple beam models were correlated initially, followed by increasingly complex and higher fidelity models of the MMA mirror segment. Subsequently, the model has been used to predict the dynamic behavior and stresses of the MMA segment in a representative spaceflight mechanical shock environment. The results of the correlation and the stresses associated with a shock event are presented herein.

Macroscopic Innervation of the Dura Mater Covering the Middle Cranial Fossa in Humans Correlated to Neurovascular Headache.

Science.gov (United States)

Lee, Shin-Hyo; Hwang, Seung-Jun; Koh, Ki-Seok; Song, Wu-Chul; Han, Sang-Don

2017-01-01

The trigeminovascular system within the cranial dura mater is a possible cause of headaches. The aim of this study is to investigate macroscopically dural innervation around the middle meningeal artery (MMA) in the middle cranial fossa. Forty-four sides of the cranial dura overlying the skull base obtained from 24 human cadavers were stained using Sihler's method. Overall, the nervus spinosus (NS) from either the maxillary or mandibular trigeminal divisions ran along the lateral wall of the middle meningeal vein rather than that of the MMA. Distinct bundles of the NS running along the course of the frontal branches of the MMA were present in 81.8% of cases ( N = 36). Others did not form dominant nerve bundles, instead giving off free nerve endings along the course of the MMA or dural connective tissue. The distribution of these nerve endings was similar to that of the course of the frontal, parietal and petrosal branches of the MMA (11.4%). The others were not restricted to a perivascular plexus, crossing the dural connective tissues far from the MMA (6.8%). These findings indicate that the NS generally travels alongside the course of the frontal branches of the MMA and terminates in the vicinity of the pterion.

Macroscopic Innervation of the Dura Mater Covering the Middle Cranial Fossa in Humans Correlated to Neurovascular Headache

Directory of Open Access Journals (Sweden)

Shin-Hyo Lee

2017-12-01

Full Text Available The trigeminovascular system within the cranial dura mater is a possible cause of headaches. The aim of this study is to investigate macroscopically dural innervation around the middle meningeal artery (MMA in the middle cranial fossa. Forty-four sides of the cranial dura overlying the skull base obtained from 24 human cadavers were stained using Sihler’s method. Overall, the nervus spinosus (NS from either the maxillary or mandibular trigeminal divisions ran along the lateral wall of the middle meningeal vein rather than that of the MMA. Distinct bundles of the NS running along the course of the frontal branches of the MMA were present in 81.8% of cases (N = 36. Others did not form dominant nerve bundles, instead giving off free nerve endings along the course of the MMA or dural connective tissue. The distribution of these nerve endings was similar to that of the course of the frontal, parietal and petrosal branches of the MMA (11.4%. The others were not restricted to a perivascular plexus, crossing the dural connective tissues far from the MMA (6.8%. These findings indicate that the NS generally travels alongside the course of the frontal branches of the MMA and terminates in the vicinity of the pterion.

Dietary sources of methylated arsenic species in urine of the United States population, NHANES 2003-2010.

Directory of Open Access Journals (Sweden)

B Rey deCastro

Full Text Available BACKGROUND: Arsenic is an ubiquitous element linked to carcinogenicity, neurotoxicity, as well as adverse respiratory, gastrointestinal, hepatic, and dermal health effects. OBJECTIVE: Identify dietary sources of speciated arsenic: monomethylarsonic acid (MMA, and dimethylarsinic acid (DMA. METHODS: Age-stratified, sample-weighted regression of NHANES (National Health and Nutrition Examination Survey 2003-2010 data (∼8,300 participants ≥6 years old characterized the association between urinary arsenic species and the additional mass consumed of USDA-standardized food groups (24-hour dietary recall data, controlling for potential confounders. RESULTS: For all arsenic species, the rank-order of age strata for median urinary molar concentration was children 6-11 years > adults 20-84 years > adolescents 12-19 years, and for all age strata, the rank-order was DMA > MMA. Median urinary molar concentrations of methylated arsenic species ranged from 0.56 to 3.52 µmol/mol creatinine. Statistically significant increases in urinary arsenic species were associated with increased consumption of: fish (DMA; fruits (DMA, MMA; grain products (DMA, MMA; legumes, nuts, seeds (DMA; meat, poultry (DMA; rice (DMA, MMA; rice cakes/crackers (DMA, MMA; and sugars, sweets, beverages (MMA. And, for adults, rice beverage/milk (DMA, MMA. In addition, based on US (United States median and 90th percentile consumption rates of each food group, exposure from the following food groups was highlighted: fish; fruits; grain products; legumes, nuts, seeds; meat, poultry; and sugars, sweets, beverages. CONCLUSIONS: In a nationally representative sample of the US civilian, noninstitutionalized population, fish (adults, rice (children, and rice cakes/crackers (adolescents had the largest associations with urinary DMA. For MMA, rice beverage/milk (adults and rice cakes/crackers (children, adolescents had the largest associations.

Disease: H01400 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available cts [DS:H00525]; Glutaric acidemia [DS:H00178]; Lysinuric protein intolerance [DS:H00899]; Pyruvate carboxyl...aired by substrate deficiencies assumed cause in various disorders including lysinuric protein intolerance,

Pharmacological evidence for GABAergic and glutamatergic involvement in the convulsant and behavioral effects of glutaric acid.

Science.gov (United States)

Lima, T T; Begnini, J; de Bastiani, J; Fialho, D B; Jurach, A; Ribeiro, M C; Wajner, M; de Mello, C F

1998-08-17

The effect of intrastriatal administration of glutaric acid (GTR), a metabolite that accumulates in glutaric acidemia type I (GA-I), on the behavior of adult male rats was investigated. After cannula placing, rats received unilateral intrastriatal injections of GTR buffered to pH 7.4 with NaOH or NaCl. GTR induced rotational behavior toward the contralateral side of injection and clonic convulsions in a dose-dependent manner. Rotational behavior was prevented by intrastriatal preadministration of DNQX and muscimol, but not by the preadministration of MK-801. Convulsions were prevented by intrastriatal preinjection of muscimol. This study provides evidence for a participation of glutamatergic non-NMDA and GABAergic mechanisms in the GTR-induced behavioral alterations. These findings may be of value in understanding the physiopathology of the neurological dysfunction in glutaric acidemia.

Effect of leaching residual methyl methacrylate concentrations on in vitro cytotoxicity of heat polymerized denture base acrylic resin processed with different polymerization cycles

Directory of Open Access Journals (Sweden)

Canan Bural

2011-08-01

Full Text Available OBJECTIVES: Residual methyl methacrylate (MMA may leach from the acrylic resin denture bases and have adverse effects on the oral mucosa. This in vitro study evaluated and correlated the effect of the leaching residual MMA concentrations ([MMA]r on in vitro cytotoxicity of L-929 fibroblasts. MATERIAL AND METHODS: A total of 144 heat-polymerized acrylic resin specimens were fabricated using 4 different polymerization cycles: (1 at 74ºC for 9 h, (2 at 74ºC for 9 h and terminal boiling (at 100ºC for 30 min, (3 at 74ºC for 9 h and terminal boiling for 3 h, (4 at 74ºC for 30 min and terminal boiling for 30 min. Specimens were eluted in a complete cell culture medium at 37ºC for 1, 2, 5 and 7 days. [MMA]r in eluates was measured using high-performance liquid chromatography. In vitro cytotoxicity of eluates on L-929 fibroblasts was evaluated by means of cell proliferation using a tetrazolium salt XTT (sodium 3´-[1-phenyl-aminocarbonyl-3,4-tetrazolium]bis(4-methoxy-6-nitrobenzenesulphonic acid assay. Differences in [MMA]r of eluates and cell proliferation values between polymerization cycles were statistically analyzed by Kruskal-Wallis, Friedman and Dunn's multiple comparison tests. The correlation between [MMA]r of eluates and cell proliferation was analyzed by Pearson's correlation test (p<0.05. RESULTS: [MMA]r was significantly (p<0.001 higher in eluates of specimens polymerized with cycle without terminal boiling after elution of 1 and 2 days. Cell proliferation values for all cycles were significantly (p<0.01 lower in eluates of 1 day than those of 2 days. The correlation between [MMA]r and cell proliferation values was negative after all elution periods, showing significance (p<0.05 for elution of 1 and 2 days. MMA continued to leach from acrylic resin throughout 7 days and leaching concentrations markedly reduced after elution of 1 and 2 days. CONCLUSION: Due to reduction of leaching residual MMA concentrations, use of terminal boiling in

Radiation induced graft copolymerization of methyl methacrylate onto chrome-tanned pig skins

International Nuclear Information System (INIS)

Pietrucha, K.; Pekala, W.; Kroh, J.

1981-01-01

Graft copolymerization of methyl methacrylate (MMA) onto chrome-tanned pig skins was carried out by irradiation with 60 Co γ-rays. The grafted polymethyl methacrylate (PMMA) chains were isolated by acid hydrolysis of the collagen backbone in order to characterize the graft copolymers. Proof of grafting was obtained through the detection of amino acid endgroups in the isolated grafts by reaction with ninhydrin. The grafting yield of MMA in aqueous emulsion was found to be higher than that for pure MMA and MMA in acetone. The degree of grafting increases with increasing monomer concentration in emulsion and reaches maximum at radiation dose ca 15 kGy. The yield of grafting is very high. The present paper reports the physical properties of chrome-tanned pig skins after graft polymerization with MMA in emulsion. Modified leathers are more resistant against water absorption and abrasion in comparison with unmodified ones. They have more uniform structure over the whole surface, greater thickness and stiffness. The mechanism of some of the processes occurring during radiation grafting of MMA in water emulsion on tanned leathers has been also suggested and discussed. (author)

Radiation induced graft copolymerization of methyl methacrylate onto chrome-tanned pig skins

Energy Technology Data Exchange (ETDEWEB)

Pietrucha, K.; Pekala, W.; Kroh, J. (Lodz Univ. (Poland))

1981-01-01

Graft copolymerization of methyl methacrylate (MMA) onto chrome-tanned pig skins was carried out by irradiation with /sup 60/Co ..gamma..-rays. The grafted polymethyl methacrylate (PMMA) chains were isolated by acid hydrolysis of the collagen backbone in order to characterize the graft copolymers. Proof of grafting was obtained through the detection of amino acid endgroups in the isolated grafts by reaction with ninhydrin. The grafting yield of MMA in aqueous emulsion was found to be higher than that for pure MMA and MMA in acetone. The degree of grafting increases with increasing monomer concentration in emulsion and reaches maximum at radiation dose ca 15 kGy. The yield of grafting is very high. The present paper reports the physical properties of chrome-tanned pig skins after graft polymerization with MMA in emulsion. Modified leathers are more resistant against water absorption and abrasion in comparison with unmodified ones. They have more uniform structure over the whole surface, greater thickness and stiffness. The mechanism of some of the processes occurring during radiation grafting of MMA in water emulsion on tanned leathers has been also suggested and discussed.

Favorable Risk Selection in Medicare Advantage: Trends in Mortality and Plan Exits Among Nursing Home Beneficiaries

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Goldberg, Elizabeth M.; Trivedi, Amal N.; Mor, Vincent; Jung, Hye-Young; Rahman, Momotazur

2016-01-01

The 2003 Medicare Modernization Act (MMA) increased payments to Medicare Advantage plans and instituted a new risk-adjustment payment model to reduce plans' incentives to enroll healthier Medicare beneficiaries and avoid those with higher costs. Whether the MMA reduced risk selection remains debatable. This study uses mortality differences, nursing home utilization, and switch rates to assess whether the MMA successfully decreased risk selection from 2000 to 2012. We found no decrease in the mortality difference or adjusted difference in nursing home use between plan beneficiaries pre- and post the MMA. Among beneficiaries with nursing home use, disenrollment from Medicare Advantage plans declined from 20% to 12%, but it remained 6 times higher than the switch rate from traditional Medicare to Medicare Advantage. These findings suggest that the MMA was not associated with reductions in favorable risk selection, as measured by mortality, nursing home use, and switch rates. PMID:27516452

Based on graphene tunable dual-band terahertz metamaterial absorber with wide-angle

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Huang, Mulin; Cheng, Yongzhi; Cheng, Zhengze; Chen, Haoran; Mao, Xuesong; Gong, Rongzhou

2018-05-01

We present a wide-angle tunable dual-band terahertz (THz) metamaterial absorber (MMA) based on square graphene patch (SGP). This MMA is a simple periodic array, consisting of a dielectric substrate sandwiched with the SGP and a continuous metallic film. The designed MMA can achieve dual-band absorption by exciting fundamental and second higher-order resonance modes on SGP. The numerical simulations indicate that the absorption spectrum of the designed MMA is tuned from 0.85 THz to 1.01 THz, and from 2.84 THz to 3.37 THz when the chemical potential of the SGP is increasing from 0.4eV to 0.8eV. Moreover, it operates well in a wide-angle of the incident waves. The presented THz MMA based on the SGP could find some potential applications in optoelectronic related devices, such as sensor, emitter and wavelength selective radiators.

Studies on Rate Enhancement of Polymerization in NMRP

Institute of Scientific and Technical Information of China (English)

HUANG Jian-ying; XU Miao-qing; YAN Ming-fa; CHEN Yi-hong; CHU Jia-yan; ZHUANG Jia-ming; DAI Li-zong; ZOU You-si

2005-01-01

In NMRP, the polymerization of MMA, the polymerization of St and the copolymerization of MMA with St were distinctly accelerated by the addition of a small amount of MN. The polymerization proceeds in a living fashion as indicated by the increase in molecular weight with the increase of time and conversion and a relatively low polydispersity. It has been found that the addition of MN results in a nearly one hundred times higher rate of the polymerization of MMA, a nearly twenty times higher rate of the polymerization of St and a nearly fifteen times higher rate of the copolymerization of St and MMA.

Ratios of One-Carbon Metabolites Are Functional Markers of B-Vitamin Status in a Norwegian Coronary Angiography Screening Cohort.

Science.gov (United States)

Ulvik, Arve; Hustad, Steinar; McCann, Adrian; Midttun, Øivind; Nygård, Ottar K; Ueland, Per M

2017-06-01

Background: Functional (metabolic) markers of B-vitamin status, including plasma total homocysteine (tHcy) for folate and plasma methylmalonic acid (MMA) for vitamin B-12, suffer from moderate sensitivity and poor specificity. Ratios of metabolites belonging to the same pathway may have better performance characteristics. Objective: We evaluated the ratios of tHcy to total cysteine (tCys; Hcy:Cys), tHcy to creatinine (Hcy:Cre), and tHcy to tCys to creatinine (Hcy:Cys:Cre) as functional markers of B-vitamin status represented by a summary score composed of folate, cobalamin, betaine, pyridoxal 5'-phosphate (PLP), and riboflavin concentrations measured in plasma. Methods: Cross-sectional data were obtained from a cohort of patients with stable angina pectoris (2994 men and 1167 women) aged 21-88 y. The relative contribution of the B-vitamin score, age, sex, smoking, body mass index, and markers of renal function and inflammation to the variance of the functional B-vitamin markers was calculated by using multiple linear regression. Results: Compared with tHcy alone, Hcy:Cys, Hcy:Cre, and Hcy:Cys:Cre all showed improved sensitivity and specificity for detecting plasma B-vitamin status. Improvements in overall performance ranged from 4-fold for Hcy:Cys to ∼8-fold for Hcy:Cys:Cre and were particularly strong in subjects with the common 5,10-methylenetetrahydrofolate reductase (MTHFR) 677CC genotype. Conclusions: Ratios of tHcy to tCys and/or creatinine showed a severalfold improvement over tHcy alone as functional markers of B-vitamin status in Norwegian coronary angiography screenees. The biological rationale for these ratios is discussed in terms of known properties of enzymes involved in the catabolism of homocysteine and synthesis of creatine and creatinine. © 2017 American Society for Nutrition.

Altered ion transport in normal human bronchial epithelial cells following exposure to chemically distinct metal welding fume particles.

Science.gov (United States)

Fedan, Jeffrey S; Thompson, Janet A; Meighan, Terence G; Zeidler-Erdely, Patti C; Antonini, James M

2017-07-01

Welding fume inhalation causes pulmonary toxicity, including susceptibility to infection. We hypothesized that airway epithelial ion transport is a target of fume toxicity, and investigated the effects of fume particulates from manual metal arc-stainless steel (MMA-SS) and gas metal arc-mild steel (GMA-MS) on ion transport in normal human bronchial epithelium (NHBE) cultured in air-interface. MMA-SS particles, more soluble than GMA-MS particles, contain Cr, Ni, Fe and Mn; GMA-MS particles contain Fe and Mn. MMA-SS or GMA-MS particles (0.0167-166.7μg/cm 2 ) were applied apically to NHBEs. After 18h transepithelial potential difference (V t ), resistance (R t ), and short circuit current (I sc ) were measured. Particle effects on Na + and Cl¯ channels and the Na + ,K + ,2Cl¯-cotransporter were evaluated using amiloride (apical), 5-nitro-2-[(3-phenylpropyl)amino]benzoic acid (NPPB, apical), and bumetanide (basolateral), respectively. MMA-SS (0.0167-16.7μg/cm 2 ) increased basal V t . Only 16.7μg/cm 2 GMA-MS increased basal V t significantly. MMA-SS or GMA-MS exposure potentiated I sc responses (decreases) to amiloride and bumetanide, while not affecting those to NPPB, GMA-MS to a lesser degree than MMA-SS. Variable effects on R t were observed in response to amiloride, and bumetanide. Generally, MMA-SS was more potent in altering responses to amiloride and bumetanide than GMA-MS. Hyperpolarization occurred in the absence of LDH release, but decreases in V t , R t , and I sc at higher fume particulate doses accompanied LDH release, to a greater extent for MMA-SS. Thus, Na + transport and Na + ,K + ,2Cl¯-cotransport are affected by fume exposure; MMA-MS is more potent than GMA-MS. Enhanced Na + absorption and decreased airway surface liquid could compromise defenses against infection. Published by Elsevier Inc.

Preservation of beech and spruce wood by allyl alcohol-based copolymers

International Nuclear Information System (INIS)

Solpan, Dilek; Gueven, Olgun

1999-01-01

Allyl alcohol (AA), acrylonitrile (AN), methyl methacrylate (MMA), monomers and monomer mixtures AA+AN, AA+MMA were used to conserve and consolidate Beech and Spruce. After impregnation, copolymerisation and polymerisation were accomplished by gamma irradiation. The fine structure of wood+polymer(copolymer) composites was investigated by Scanning Electron Microscopy (SEM). It was observed that copolymer obtained from AA+MMA monomer mixture showed the optimum compatibility. The compressional strength and Brinell Hardness Numbers determined for untreated and treated wood samples indicated that the mechanical strength of wood+copolymer composites was increased. It was found that the mechanical strength of the wood samples containing the AA+MMA copolymer was higher than the others. In the presence of P(AA/MMA), at highest conversion, the compressive strength perpendicular to the fibres in Beech and Spruce increased approximately 100 times. The water uptake capacity of wood+copolymer composites was observed to decrease by more than 50% relative to the original samples, and biodegradation did not take place

Copolymerization of Styrene and Methacrylates in the presence of Catalytic Chain Transfer Agents (Cacti's)

International Nuclear Information System (INIS)

Hussain, M.Sakhawat; Khan, M.A.; Ahmad, Shafique

2005-01-01

The present paper focuses on the use of a Co (II) complex, [Co(afdo-H)] as a catalytic chain transfer agent (CCTA) for controlling molecular weight in copolymerization of styrene (STY) with butyl methacrylate (BMA) and methylmethacrylate (MMA). The catalyst is structurally similar to [co(dmg-H) (BF)] patented by Du Pont as a CCTA. Average catalytic chain transfer constant, C8 of [co(afdo-H) (BF)] for coplymerization of STY with BMA and MMA determined from Maya plot, was found to be in the range of 10-10.This value is lower than the value reported for the [Co(dmg-H)(BF)). In the case of STY-BMA or STY-MMA copolymerization, a considerable reduction in the viscosity average molecular weights (Mv) was observed in the copolymers. The average molecular weight of poly (MMA-BMA) was reduced by a factor of ten compared to the reduction in poly (STY-MMA) and poly (STY-BMA) for the same concentration of the CCTA. (author)

Ethanol Induced Urine Acidification is Related with Early Acetaldehyde Concentration

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Soon Kil Kwon

2014-06-01

Conclusion: In conclusion, urine acidification after ethanol ingestion is related with serum acetaldehyde concentration. Early elevation of acetaldhyde could induce urine acidification, but the urine pH was elevated after a few hours, that might make prolonged acidemia.

Microencapsulated n-octadecane with different methylmethacrylate-based copolymer shells as phase change materials for thermal energy storage

International Nuclear Information System (INIS)

Qiu, Xiaolin; Li, Wei; Song, Guolin; Chu, Xiaodong; Tang, Guoyi

2012-01-01

Microcapsules containing n-octadecane with different methylmethacrylate (MMA (methyl methacrylate))-based copolymer shells were fabricated by a suspension-like polymerization. Butyl acrylate (BA), butyl methacrylate (BMA), lauryl methacrylate (LMA) and stearyl methacrylate (SMA) were employed as monomers to copolymerize with MMA. Pentaerythritol tetraacrylate (PETRA) was employed as a crosslinking agent. The (microencapsulted phase change materials) MicroPCMs were characterized using Fourier transformed infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Thermal properties and thermal resistances of MicroPCMs were investigated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. Phase change enthalpies and PCM contents of MicroPCMs increased with the length decreasing of the side chain of the monomers. The n-octadecane content of as much as 77.3% can be obtained in the crosslinked MicroPCMs with P(MMA-co-BMA) as shell, and accompanied by the highest melting enthalpy (173.7 J/g) and crystallization enthalpy (174.4 J/g). Heat capacities of crosslinked MicroPCMs are higher than those of their uncrosslinked counterparts. The crosslinked MicroPCMs exhibit significantly greater thermal stabilities compared with their uncrosslinked counterparts and the n-ontadecane bulk. The crosslinked MicroPCMs with P(MMA-co-SMA) displays the highest thermal resistance temperature up to 255 °C. Therefore, MicroPCMs with MMA-based copolymer as shells, especially crosslinked copolymer shells, show excellent potentials for thermal energy storage. -- Highlights: ► n-Octadecane was encapsulated with methylmethacrylate(MMA)-based copolymer shells. ► n-Octadecane content of Microcapsules increased with length decreasing of side chain of monomers. ► Microcapsule with P(MMA-co-butyl methacrylate) has the highest latent heat. ► Microcapsule with P(MMA-co-stearyl methacrylate) has the greatest thermal stability.

Dietary intake in Australian children aged 4-24 months: consumption of meat and meat alternatives.

Science.gov (United States)

Mauch, Chelsea Emma; Perry, R A; Magarey, A M; Daniels, L A

2015-06-14

Meat/meat alternatives (M/MA) are key sources of Fe, Zn and protein, but intake tends to be low in young children. Australian recommendations state that Fe-rich foods, including M/MA, should be the first complementary foods offered to infants. The present paper reports M/MA consumption of Australian infants and toddlers, compares intake with guidelines, and suggests strategies to enhance adherence to those guidelines. Mother-infant dyads recruited as part of the NOURISH and South Australian Infants Dietary Intake studies provided 3 d of intake data at three time points: Time 1 (T1) (n 482, mean age 5·5 (SD 1·1) months), Time 2 (T2) (n 600, mean age 14·0 (SD 1·2) months) and Time 3 (T3) (n 533, mean age 24 (SD 0·7) months). Of 170 infants consuming solids and aged greater than 6 months at T1, 50 (29%) consumed beef, lamb, veal (BLV) or pork on at least one of 3 d. Commercial infant foods containing BLV or poultry were the most common form of M/MA consumed at T1, whilst by T2 BLV mixed dishes (including pasta bolognaise) became more popular and remained so at T3. The processed M/MA increased in popularity over time, led by pork (including ham). The present study shows that M/MA are not being eaten by Australian infants or toddlers regularly enough; or in adequate quantities to meet recommendations; and that the form in which these foods are eaten can lead to smaller M/MA serve sizes and greater Na intake. Parents should be encouraged to offer M/MA in a recognisable form, as one of the first complementary foods, in order to increase acceptance at a later age.

Arsenic Exposure, Arsenic Metabolism, and Incident Diabetes in the Strong Heart Study

Science.gov (United States)

Howard, Barbara V.; Umans, Jason G.; Gribble, Matthew O.; Best, Lyle G.; Francesconi, Kevin A.; Goessler, Walter; Lee, Elisa; Guallar, Eliseo; Navas-Acien, Ana

2015-01-01

OBJECTIVE Little is known about arsenic metabolism in diabetes development. We investigated the prospective associations of low-moderate arsenic exposure and arsenic metabolism with diabetes incidence in the Strong Heart Study. RESEARCH DESIGN AND METHODS A total of 1,694 diabetes-free participants aged 45–75 years were recruited in 1989–1991 and followed through 1998–1999. We used the proportions of urine inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) over their sum (expressed as iAs%, MMA%, and DMA%) as the biomarkers of arsenic metabolism. Diabetes was defined as fasting glucose ≥126 mg/dL, 2-h glucose ≥200 mg/dL, self-reported diabetes history, or self-reported use of antidiabetic medications. RESULTS Over 11,263.2 person-years of follow-up, 396 participants developed diabetes. Using the leave-one-out approach to model the dynamics of arsenic metabolism, we found that lower MMA% was associated with higher diabetes incidence. The hazard ratios (95% CI) of diabetes incidence for a 5% increase in MMA% were 0.77 (0.63–0.93) and 0.82 (0.73–0.92) when iAs% and DMA%, respectively, were left out of the model. DMA% was associated with higher diabetes incidence only when MMA% decreased (left out of the model) but not when iAs% decreased. iAs% was also associated with higher diabetes incidence when MMA% decreased. The association between MMA% and diabetes incidence was similar by age, sex, study site, obesity, and urine iAs concentrations. CONCLUSIONS Arsenic metabolism, particularly lower MMA%, was prospectively associated with increased incidence of diabetes. Research is needed to evaluate whether arsenic metabolism is related to diabetes incidence per se or through its close connections with one-carbon metabolism. PMID:25583752

Exposure to monomethylarsonous acid (MMAIII) leads to altered selenoprotein synthesis in a primary human lung cell model

International Nuclear Information System (INIS)

Meno, Sarah R.; Nelson, Rebecca; Hintze, Korry J.; Self, William T.

2009-01-01

Monomethylarsonous acid (MMA III ), a trivalent metabolite of arsenic, is highly cytotoxic and recent cell culture studies suggest that it might act as a carcinogen. The general consensus of studies indicates that the cytotoxicity of MMA III is a result of increased levels of reactive oxygen species (ROS). A longstanding relationship between arsenic and selenium metabolism has led to the use of selenium as a supplement in arsenic exposed populations, however the impact of organic arsenicals (methylated metabolites) on selenium metabolism is still poorly understood. In this study we determined the impact of exposure to MMA III on the regulation of expression of TrxR1 and its activity using a primary lung fibroblast line, WI-38. The promoter region of the gene encoding the selenoprotein thioredoxin reductase 1 (TrxR1) contains an antioxidant responsive element (ARE) that has been shown to be activated in the presence of electrophilic compounds. Results from radiolabeled selenoproteins indicate that exposure to low concentrations of MMA III resulted in increased synthesis of TrxR1 in WI-38 cells, and lower incorporation of selenium into other selenoproteins. MMA III treatment led to increased mRNA encoding TrxR1 in WI-38 cells, while lower levels of mRNA coding for cellular glutathione peroxidase (cGpx) were detected in exposed cells. Luciferase activity of TrxR1 promoter fusions increased with addition of MMA III , as did expression of a rat quinone reductase (QR) promoter fusion construct. However, MMA III induction of the TRX1 promoter fusion was abrogated when the ARE was mutated, suggesting that this regulation is mediated via the ARE. These results indicate that MMA III alters the expression of selenoproteins based on a selective induction of TrxR1, and this response to exposure to organic arsenicals that requires the ARE element.

Recurrent rhabdomyolysis and glutaric aciduria type I: a case report and literature review.

Science.gov (United States)

Qian, Gu-Ling; Hong, Fang; Tong, Fan; Fu, Hai-Dong; Liu, Ai-Min

2016-08-01

Glutaric acidemia type I (GA-I) is a rare metabolic disorder caused by mutation of the glutaryl- CoA dehydrogenase (GCDH) gene. The occurrence of rhabdomyolysis with GA-I is extremely rare. We reported a child with recurrent rhabdomyolysis and undiagnosed glutaric acidemia type I (GA-I). And a literature review was performed. A 4.5-year-old girl was admitted to our hospital due to recurrent rhabdomyolysis for 3 times within three years. At the third admission, she was diagnosed with GA-I by biochemical testing and mutation analysis. The girl was found to have a serine to leucine replacement mutation of the GCDH gene in exon 8 at position 764. Other three patients with rhabdomyolysis and GA-I were discovered by literature searching. This report highlights that patients with GA-I may have an increased risk of rhabdomyolysis.

Considerations on the Media and "Sports Heroes" of Mixed Martial Arts

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Igor Sampaio Pinho Dos Santos

2015-05-01

Full Text Available The text presents some considerations about mechanisms used by the media industry in the construction of "sports heroes" of Mixed Martial Arts (MMA. For that, there was a theoretical study and highlighted a few examples of situations experienced by Brazilian MMA athletes to discuss such mechanisms. Thus, it is understood that the sporting spectacle, the use of specialized marketing and sensationalism in the dissemination of information about the lives of these athletes are some of the mechanisms used by the media in the construction of MMA heroes. We conclude that this is one of the most effective strategies to transform the MMA a popular phenomenon, encouraging their consumption sold in Brazilian society.

Investigation of nanocomposites made with poly(methacrylic acid-co-methyl methacrylate/poly(N-vinyl-2-pyrrolidone/multi-walled carbon nanotubes

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Liu Guoqin

2014-01-01

Full Text Available Poly(methacrylic acid-co-methyl methacrylate (P(MAA-co-MMA was prepared in the presence of poly(N-vinyl-2-pyrrolidone (PVP and multiwalled carbon nanotubes (MWNTs via ultrasonic assisted solution free radical polymerization, i.e., P(MAA-co-MMA/PVP/MWNTs nanocomposites. The morphology, glassy-state storage modulus, thermal behavior and swelling characteristics of P(MAA-co-MMA/PVP/MWNTs nanocomposites were investigated. Scanning electron micrographs (SEM revealed that MWNTs at low concentration could be uniformly dispersed into P(MAA-co-MMA/PVP blends. With increasing MWNTs weight fraction, the average glassy-state modulus, glass transition temperatures and decomposition temperature of the nanocomposites increased, but their swelling characteristics decreased.

Investigation of nanocomposites made with poly(methacrylic acid-co-methyl methacrylate)/poly(N-vinyl-2-pyrrolidone)/multi-walled carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Guoqin, Liu; Wei, Miao [College of Material Science and Engineering, Henan University of Technology (China); Lin-Jian, Shangguan, E-mail: mikepolymer@126.com [School of Mechanical Engineering, North China University of Water Conservancy and Electric Power (China)

2014-06-01

Poly(methacrylic acid-co-methyl methacrylate) (P(MAA-co-MMA)) was prepared in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) and multi-walled carbon nanotubes (MWNTs) via ultrasonic assisted solution free radical polymerization, i.e., P(MAA-co-MMA)/PVP/MWNTs nanocomposites. The morphology, glassy-state storage modulus, thermal behavior and swelling characteristics of P(MAA-co-MMA)/PVP/MWNTs nanocomposites were investigated. Scanning electron micrographs (SEM) revealed that MWNTs at low concentration could be uniformly dispersed into P(MAA-co-MMA)/PVP blends. With increasing MWNTs weight fraction, the average glassy-state modulus, glass transition temperatures and decomposition temperature of the nanocomposites increased, but their swelling characteristics decreased. (author)

Induction of glutathione S-transferase placental form positive foci in liver and epithelial hyperplasia in urinary bladder, but no tumor development in male Fischer 344 rats treated with monomethylarsonic acid for 104 weeks

International Nuclear Information System (INIS)

Shen Jun; Wanibuchi, Hideki; Salim, Elsayed I.; Wei Min; Doi, Kenichiro; Yoshida, Kaoru; Endo, Ginji; Morimura,; Fukushima, Shoji

2003-01-01

The carcinogenicity of monomethylarsonic acid (MMA(V)), a major metabolite of inorganic arsenics in human and experimental animals, was investigated in male Fischer 344 rats. A total of 129 rats at 10 weeks of age were randomly divided into three groups and received drinking water containing MMA(V) at doses of 0 (Control), 50, and 200 ppm ad libitum for 104 weeks. No significant differences were found between the control and the MMA(V)-treated groups regarding clinical signs, mortality, hematological, and serum biochemistry findings. Quantitative analysis of glutathione S-transferase placental form (GST-P) positive foci in liver revealed a significant increase of numbers and areas in the 200 ppm MMA(V)-treated group. In the urinary bladder MMA(V) induced simple hyperplasia and significantly elevated the proliferating cell nuclear antigen (PCNA)-positive index in the urothelium. A variety of tumors developed in rats of all groups, including the controls, but all were histologically similar to those known to occur spontaneously in F344 rats and there were no significant differences among the groups. Thus, it could be concluded that, under the present experimental conditions, MMA(V) induced lesions in the liver and urinary bladder, but did not cause tumor development in male F344 rats even after 2 years exposure

Methyl methacrylate and respiratory sensitization: A Critical review

Science.gov (United States)

Borak, Jonathan; Fields, Cheryl; Andrews, Larry S; Pemberton, Mark A

2011-01-01

Methyl methacrylate (MMA) is a respiratory irritant and dermal sensitizer that has been associated with occupational asthma in a small number of case reports. Those reports have raised concern that it might be a respiratory sensitizer. To better understand that possibility, we reviewed the in silico, in chemico, in vitro, and in vivo toxicology literature, and also epidemiologic and occupational medicine reports related to the respiratory effects of MMA. Numerous in silico and in chemico studies indicate that MMA is unlikely to be a respiratory sensitizer. The few in vitro studies suggest that MMA has generally weak effects. In vivo studies have documented contact skin sensitization, nonspecific cytotoxicity, and weakly positive responses on local lymph node assay; guinea pig and mouse inhalation sensitization tests have not been performed. Cohort and cross-sectional worker studies reported irritation of eyes, nose, and upper respiratory tract associated with short-term peaks exposures, but little evidence for respiratory sensitization or asthma. Nineteen case reports described asthma, laryngitis, or hypersensitivity pneumonitis in MMA-exposed workers; however, exposures were either not well described or involved mixtures containing more reactive respiratory sensitizers and irritants.The weight of evidence, both experimental and observational, argues that MMA is not a respiratory sensitizer. PMID:21401327

Silicon Decreases Dimethylarsinic Acid Concentration in Rice Grain and Mitigates Straighthead Disorder.

Science.gov (United States)

Limmer, Matthew Alan; Wise, Patrick; Dykes, Gretchen E; Seyfferth, Angelia L

2018-04-17

While root Si transporters play a role in the uptake of arsenite and organic As species dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) in rice ( Oryza sativa L.), the impact of Si addition on the accumulation of DMA and MMA in reproductive tissues has not been directly evaluated, particularly in isolation from inorganic As species. Furthermore, DMA and MMA are suspected causal agents of straighthead disorder. We performed a hydroponic study to disentangle the impact of Si on accumulation of DMA and MMA in rice grain. At 5 μM, MMA was toxic to rice, regardless of Si addition, although Si significantly decreased root MMA concentrations. Plants dosed with 5 μM DMA grew well vegetatively but exhibited straighthead disorder at the lowest Si dose, and this DMA-induced yield loss reversed with increasing solution Si. Increasing Si also significantly decreased DMA concentrations in roots, straw, husk, and grain, particularly in mature plants. Si restricted grain DMA through competition for root uptake and downregulation of root Si transporters particularly at later stages of growth when Si uptake was greatest. Our finding that DMA causes straighthead disorder under low Si availability but not under high Si availability suggests Si as a straighthead management strategy.

STUDIES ON ORGANIC PEROXIDE / N ,N-DI (2-α-METHYL-ACRYLOYLOXY PROPYL) -PARA-TOLUIDINE BINARY SYSTEMS

Institute of Scientific and Technical Information of China (English)

QIU Kunyuan; FU Jie; GUO Xinqiu; FENG Xinde

1990-01-01

The polymerization of methyl methacrylate ( MMA )initiated by organic peroxide and polymerizable aromatic tertiary amine such as N,N-di (2-α-methylacryloyloxy propyl )-p- toluidine (MP)2PT binary system has been studied . It was found that the ( MP )2PT promotes MMA polymerization, and the kinetics of MMA polymerization fits the radical polymerization rate equation . Based on the ESR studies and the end-group analysis the initiation mechanism is proposed.

Tandem Mass Neonatal Screening in Taiwan—Report from One Center

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Hsiang-Po Huang

2006-01-01

Conclusion: We found that MS/MS neonatal screening was valuable in the early diagnosis of severe and treatable inborn errors of metabolism such as organic acidemias and urea cycle disorders. It also detected less severe disorders that required only observation.

Association between body mass index and arsenic methylation efficiency in adult women from southwest U.S. and northwest Mexico

International Nuclear Information System (INIS)

Gomez-Rubio, Paulina; Roberge, Jason; Arendell, Leslie; Harris, Robin B.; O'Rourke, Mary K.; Chen, Zhao; Cantu-Soto, Ernesto; Meza-Montenegro, Maria M.; Billheimer, Dean; Lu Zhenqiang; Klimecki, Walter T.

2011-01-01

Human arsenic methylation efficiency has been consistently associated with arsenic-induced disease risk. Interindividual variation in arsenic methylation profiles is commonly observed in exposed populations, and great effort has been put into the study of potential determinants of this variability. Among the factors that have been evaluated, body mass index (BMI) has not been consistently associated with arsenic methylation efficiency; however, an underrepresentation of the upper BMI distribution was commonly observed in these studies. This study investigated potential factors contributing to variations in the metabolism of arsenic, with specific interest in the effect of BMI where more than half of the population was overweight or obese. We studied 624 adult women exposed to arsenic in drinking water from three independent populations. Multivariate regression models showed that higher BMI, arsenic (+ 3 oxidation state) methyltransferase (AS3MT) genetic variant 7388, and higher total urinary arsenic were significantly associated with low percentage of urinary arsenic excreted as monomethylarsonic acid (%uMMA) or high ratio between urinary dimethylarsinic acid and uMMA (uDMA/uMMA), while AS3MT genetic variant M287T was associated with high %uMMA and low uDMA/uMMA. The association between BMI and arsenic methylation efficiency was also evident in each of the three populations when studied separately. This strong association observed between high BMI and low %uMMA and high uDMA/uMMA underscores the importance of BMI as a potential arsenic-associated disease risk factor, and should be carefully considered in future studies associating human arsenic metabolism and toxicity.

Surgical anatomy and preservation of the middle meningeal artery during bypass surgery for moyamoya disease.

Science.gov (United States)

Hori, Satoshi; Kashiwazaki, Daina; Akioka, Naoki; Hayashi, Tomohide; Hori, Emiko; Umemura, Kimiko; Horie, Yukio; Kuroda, Satoshi

2015-01-01

The middle meningeal artery (MMA) is known to function as one of the important collateral routes in moyamoya disease. However, the anterior branch frequently courses within the lesser wing of the sphenoid bone and can easily be damaged during craniotomy for bypass surgery. This prospective study aimed to study the surgical anatomy of the MMA and to establish the technique to preserve it during bypass surgery for moyamoya disease. Twenty-two patients with moyamoya disease underwent STA-MCA anastomosis combined with indirect bypass on 27 sides. The anatomical relationship between the anterior branch of the MMA and lesser wing was classified into three types: the bridge, monorail, and tunnel types. During surgery, the lesser wing was carefully resected with a rongeur or high-speed diamond drill to preserve the anterior branch of the MMA. The anterior branch of the MMA was classified into the bridge type in 5 sides (18.5 %), monorail type in 10 sides (37.0 %), and tunnel type in 12 sides (44.5 %). Patient age was closely related to the anatomical findings (χ (2) test, p = 0.0168). Careful resection of the lesser wing with a rongeur could preserve bridge- and monorail-type MMAs (100 and 71.4 %, respectively). However, drilling out of the lesser wing under a surgical microscope was essential to preserve the tunnel-type MMA. Intraoperative indocyanine green videoangiography was useful to confirm patency during surgery. It is essential to understand the surgical anatomy of the MMA around the pterion in order to preserve its anterior branch during bypass surgery for moyamoya disease.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

https://www.ias.ac.in/article/fulltext/jgen/094/02/0295-0298. Keywords. methylmalonic academia; prenatal diagnosis; carrier identification; genetic counselling. Author Affiliations. Ameya Paleja1 Anuradha Udumudi1. ATS GeneTech Private Limited, 6-3-1113/4, GVR Villa, Behind BS Makhtha Maisamma Temple, Greenlands, ...

Blockade and enhancement of glutamate receptor responses in Xenopus oocytes by methylated arsenicals

Energy Technology Data Exchange (ETDEWEB)

Krueger, Katharina; Gruner, Janina; Madeja, Michael; Musshoff, Ulrich [Universitaetsklinikum Muenster, Institut fuer Physiologie I, Muenster (Germany); Hartmann, Louise M.; Hirner, Alfred V. [Universitaet Duisburg-Essen, Institut fuer Umweltanalytik, Essen (Germany); Binding, Norbert [Universitaetsklinikum Muenster, Institut fuer Arbeitsmedizin, Muenster (Germany)

2006-08-15

Pentavalent and trivalent organoarsenic compounds belong to the major metabolites of inorganic arsenicals detected in humans. Recently, the question was raised whether the organic arsenicals represent metabolites of a detoxification process or methylated species with deleterious biological effects. In this study, the effects of trivalent arsenite (AsO{sub 3} {sup 3-}; iA{sup III}), the pentavalent organoarsenic compounds monomethylarsonic acid (CH{sub 3}AsO(OH){sub 2}; MMA{sup V}) and dimethylarsinic acid ((CH{sub 3}){sub 2}AsO(OH); DMA{sup V}) and the trivalent compounds monomethylarsonous acid (CH{sub 3}As(OH){sub 2}, MMA{sup III}) and dimethylarsinous acid ((CH{sub 3}){sub 2}As(OH); DMA{sup III}) were tested on glutamate receptors and on voltage-operated potassium and sodium channels heterologously expressed in Xenopus oocytes. Membrane currents of ion channels were measured by conventional two-electrode voltage-clamp techniques. The effects of arsenite were tested in concentrations of 1-1,000 {mu}mol/l and the organic arsenical compounds were tested in concentrations of 0.1-100 {mu}mol/l. We found no significant effects on voltage-operated ion channels; however, the arsenicals exert different effects on glutamate receptors. While MMA{sup V} and MMA{sup III} significantly enhanced ion currents through N-methyl-d-aspartate (NMDA) receptor ion channels with threshold concentrations <10 {mu}mol/l, DMA{sup V} and DMA{sup III} significantly reduced NMDA-receptor mediated responses with threshold concentrations <0.1 {mu}mol/l; iA{sup III} had no effects on glutamate receptors of the NMDA type. MMA{sup III} and DMA{sup V} significantly reduced ion currents through {alpha}-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-receptor ion channels with threshold concentrations <10 {mu}mol/l (MMA{sup III}) and <1 {mu}mol/l (DMA{sup V}). MMA{sup V} and iA{sup III} had no significant effects on glutamate receptors of the AMPA type. The effects of MMA{sup V}, MMA

An empirical investigation on the forecasting ability of mallows model averaging in a macro economic environment

Science.gov (United States)

Yin, Yip Chee; Hock-Eam, Lim

2012-09-01

This paper investigates the forecasting ability of Mallows Model Averaging (MMA) by conducting an empirical analysis of five Asia countries, Malaysia, Thailand, Philippines, Indonesia and China's GDP growth rate. Results reveal that MMA has no noticeable differences in predictive ability compared to the general autoregressive fractional integrated moving average model (ARFIMA) and its predictive ability is sensitive to the effect of financial crisis. MMA could be an alternative forecasting method for samples without recent outliers such as financial crisis.

‘It is what it is’: Masculinity, homosexuality, and inclusive discourse in mixed martial arts

OpenAIRE

Channon, Alex; Matthews, Christopher R.

2015-01-01

In this paper we make use of inclusive masculinity theory to explore online media representations of male homosexuality and masculinity within the increasingly popular combat sport of mixed martial arts (MMA). Adopting a case-study approach, we discuss narratives constructed around one aspirational male MMA fighter, Dakota Cochrane, whose history of having participated in gay pornography became a major talking point on a number of MMA ‘fanzine’/‘community’ websites during early 2012. While th...

Uso de bicarbonato de sódio na acidose metabólica do paciente gravemente enfermo Sodium bicarbonate in the critically lll patient with metabolic acidosis

Directory of Open Access Journals (Sweden)

Paulo Novis Rocha

2009-12-01

Full Text Available A acidose lática é um distúrbio do equilíbrio ácido-base muito frequente em pacientes internados em unidades de terapia intensiva e está associado a um mau prognóstico. Embora exista um acúmulo substancial de evidências de que níveis críticos de acidemia provocam inúmeros efeitos adversos sobre o funcionamento celular, a utilização de bicarbonato de sódio para o tratamento da acidose lática em pacientes gravemente enfermos permanece alvo de controvérsias. Neste artigo, pretendemos: 1 analisar as principais diferenças entre as acidoses hiperclorêmicas e as acidoses orgânicas, com ânion gap (AG elevado, visando embasar a discussão sobre os fundamentos da terapia com bicarbonato de sódio nas acidoses metabólicas; 2 avaliar os riscos associados à persistência de níveis críticos de acidemia, contrastando-os com os riscos do uso de bicarbonato de sódio; 3 analisar criticamente as evidências da literatura sobre o uso de bicarbonato de sódio no tratamento da acidose lática do paciente crítico, com ênfase em ensaios clínicos randomizados em seres humanos; 4 fornecer um fundamento para a utilização judiciosa de bicarbonato de sódio nesta situação.Lactic acidosis is an acid-base imbalance frequently found in critically ill patients. It is associated with a poor prognosis. Despite the substantial body of evidence that critical levels of acidemia have several adverse effects on cell function, the use of sodium bicarbonate to treat lactic acidosis in critically ill patients remains highly controversial. This article aimed at: 1 analyzing the main differences between hyperchloremic and organic acidoses, with high anion gap; 2 comparing the risks associated with critical levels of acidemia with those associated with the use of sodium bicarbonate; 3 critically analyzing the literature evidence about the use of sodium bicarbonate for the treatment of lactic acidosis in critically ill patients, with an emphasis on randomized

Study on the production of kanvas shoes adhesive from natural rubber latex grafted with methyl methacrylate (NRL-g PMMA) copolymer

International Nuclear Information System (INIS)

Utama, Marga; Sudirman; Setyowati, Penny

2002-01-01

The optimation condition of radiation copolymerization of MMA into natural rubber latex at the doses of radiation : 5; 7.5 and 10 kGy with concentration of MMA 25; 50; 75; and 100 phr (Part Hundred Ratio of Rubber) expectially and optimazation condition of the adhesive process all the production of canvas shoes have been carried out. The properties of NRL-g-MMA and its rubber such as total solid contain, viscosity, pH, modulus, tensile, strenght, hardnes, elongation at break, and adhesive strenght for producting canvas shoes where evaluated. The at adhesive results show that NRL-g-MMA with the 75 phr of MMA and iradiation dose 5 kGy is adhesive will good stability during storage. The adhesive strenght of shoes its 16-18 N/6mm, more here than SNI 1-0172-1987 with the value 10N/6mm. Besic there is a tendency that adhesive strengt of product shoes at rome temperature (30-50 o C). stronger than at high temperature (100 o C)

In situ development of self-reinforced cellulose nanocrystals based thermoplastic elastomers by atom transfer radical polymerization.

Science.gov (United States)

Yu, Juan; Wang, Chunpeng; Wang, Jifu; Chu, Fuxiang

2016-05-05

Recently, the utilization of cellulose nanocrystals (CNCs) as a reinforcing material has received a great attention due to its high elastic modulus. In this article, a novel strategy for the synthesis of self-reinforced CNCs based thermoplastic elastomers (CTPEs) is presented. CNCs were first surface functionalized with an initiator for surface-initiated atom transfer radical polymerization (SI-ATRP). Subsequently, SI-ATRP of methyl methacrylate (MMA) and butyl acrylate (BA) was carried out in the presence of sacrificial initiator to form CTPEs in situ. The CTPEs together with the simple blends of CNCs and linear poly(MMA-co-BA) copolymer (P(MMA-co-BA)) were characterized for comparative study. The results indicated that P(MMA-co-BA) was successfully grafted onto the surface of CNCs and the compatibility between CNCs and the polymer matrix in CTPEs was greatly enhanced. Specially, the CTPEs containing 2.15wt% CNCs increased Tg by 19.2°C and tensile strength by 100% as compared to the linear P(MMA-co-BA). Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis and characterization of poly (n-butyl acrylate)-poly (methyl methacrylate) latex interpenetrating polymer networks by radiation-induced seeded emulsion polymerization

Energy Technology Data Exchange (ETDEWEB)

Yu Haibo [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Peng Jing [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)], E-mail: jpeng@pku.edu.cn; Zhai Maolin; Li Jiuqiang; Wei Genshuan [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Qiao Jinliang [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); SINOPEC Beijing Research Institute of Chemical Industry, Beijing 100013 (China)

2007-11-15

A series of latex interpenetrating polymer networks (LIPNs) were prepared via a two-stage emulsion polymerization of methyl methacrylate (MMA) or mixture of MMA and n-butyl acrylate (n-BA) on crosslinked poly(n-butyl acrylate)(PBA) seed latex using {sup 60}Co {gamma}-ray radiation. The particles of resultant latex were produced with diameters between 150 and 250 nm. FTIR spectra identified the formation of crosslinked copolymers of PMMA or P(MMA-co-BA). Dynamic light scattering (DLS) showed that with increasing n-BA concentration in second-stage monomers, the particle size of LIPN increased. Transmission electron microscope(TEM) photographs showed that the morphology of resultant acrylate interpenetrating polymer network (IPN) latex varied from the distinct core-shell structure to homogenous particle structure with the increase of n-BA concentration, and the morphology was mainly controlled by the miscibility between crosslinked PBA seed and second-stage copolymers and polarity of P(MMA-co-BA)copolymers. In addition, differential scanning calorimeter (DSC) measurements indicated the existence of reinforced miscibility between PBA seed and P(MMA-co-BA)copolymer in prepared LIPNs.

A sustained release system using porous cellulose spheres modified by grafting as matrices

International Nuclear Information System (INIS)

Hosoi, Fumio; Makuuchi, Keizo; Saito, Kenji; Koishi, Masumi.

1987-01-01

Polymer-coated spheres, obtained by the graft polymerization of methyl methacrylate (MMA) onto porous spheres based on cellulose by the pre-irradiation method, were used as matrices for the drug sustained release system for salicylic acid. The adsorption of salicylic acid was carried out by dipping the grafted spheres in a 50% aqueous ethanol solution containing salicylic acid. The amount of salicylic acid adsorbed (Q) increased proportionately with the percent graft of MMA (G) to the power of 2.9. Adsorption mechanism of salicylic acid could be expressed in term of Langmuir's adsorption isotherm. The ratio of constants for adsorption and desorption (k) and the saturated amount of salicylic acid adsorbed (Q 0 ) were expressed as k = k 1 G and Q 0 = k 2 G 2.4 , respectively. These results indicate that the number of adsorption sites increased proportionately with the nth power of G as a results of the interaction of grafted poly (methyl methacrylate)(PMMA) and cellulose. Similar results were obtained with grafting of MMA, MMA-styrene (St), and MMA-methacrylic acid (MAc) in the presence of salicylic acid. (author)

DESIGN AND CONTROL OF SOAP-FREE HYDROPHILIC-HYDROPHOBIC CORE-SHELL LATEX PARTICLES WITH HIGH CARBOXYL CONTENT IN THE CORE OF THE PARTICLES

Institute of Scientific and Technical Information of China (English)

Wen-jiao Ji; Yi-ming Jiang; Bo-tian Li; Wei Deng; Cheng-you Kan

2012-01-01

Soap-free hydrophilic-hydrophobic core-shell latex particles with high carboxyl content in the core of the particles were synthesized via the seeded emulsion polymerization using methyl methacrylate (MMA),butyl acrylate (BA),methacrylic acid (MAA),styrene (St) and ethylene glycol dimethacrylate (EGDMA) as monomers,and the influences of MMA content used in the core preparation on polymerization,particle size and morphology were investigated by transmission electron microscopy,dynamic light scattering and conductometric titration.The results showed that the seeded emulsion polymerization could be carried out smoothly using "starved monomer feeding process" when MAA content in the core preparation was equal to or less than 24 wt％,and the encapsulating efficiency of the hydrophilic P(MMA-BA-MAA-EGDMA) core with the hydrophobic PSt shell decreased with the increase in MAA content.When an interlayer of P(MMA-MAA-St) with moderate polarity was inserted between the P(MMA-BA-MAA-EGDMA) core and the PSt shell,well designed soap-free hydrophilic-hydrophobic core-shell latex particles with 24 wt％ MAA content in the core preparation were obtained.

KINETICS OF SUSPENDED EMULSION POLYMERIZATION OF METHYL METHACRYLATE

Institute of Scientific and Technical Information of China (English)

Yong-zhong Bao; Cheng-xi Wang; Zhi-ming Huang; Zhi-xue Weng

2004-01-01

The kinetics of suspended emulsion polymerization of methyl methacrylate (MMA), in which water acted as the dispersed phase and the mixture of MMA and cyclohexane as the continuous phase, was investigated. It showed that the initial polymerization rate (Rp0) and steady-state polymerization rate (Rp) were proportional to the mass ratio between water and oil phase, and increased as the polymerization temperature, the potassium persulphate concentration ([I]) and the Tween20 emulsifier concentration ([S]) increased. The relationships between the polymerization rate and [I] and [S] were obtained as follows: Rp0 ∝ [I]0.73[S]0.32 and Rp ∝ [I]0.71[S]0.23. The above exponents were close to those obtained from normal MMA emulsion polymerization. It also showed that the average molecular weight of the resulting poly(methyl methacrylate) decreased as the polymerization temperature, [I] and [S] increased. Thus, MMA suspended emulsion polymerization could be considered as a combination of many miniature emulsion polymerizations proceeding in water drops and obeyed the classical kinetics of MMA emulsion polymerization.

Avaliação de monômero residual em resinas acrílicas de uso ortodôntico e protético: análise por espectroscopia Evaluation of residual monomer in autopolymerizing acrylic resins: spectroscopy analysis

Directory of Open Access Journals (Sweden)

Roberto Rocha Filho

2007-04-01

Full Text Available OBJETIVO: duas marcas comerciais de resinas acrílicas ativadas quimicamente (RAAQ, uma de uso ortodôntico (Orto Cril® e outra de uso protético (Jet®, polimerizadas em presença e ausência de pressão, foram analisadas em relação ao conteúdo de monômero (MMA residual liberado em solução, em diferentes intervalos de tempo (0,083; 0,25; 1; 1,25; 2,17; 5; 9; 14 e 21 dias. METODOLOGIA: a espectroscopia de absorção no ultravioleta foi utilizada na análise de soluções aquosas de MMA, com concentrações conhecidas, visando a determinação de uma curva de calibração. Soluções aquosas contendo corpos-de-prova, confeccionados com as citadas RAAQ, foram também submetidas à análise por espectroscopia de absorção no ultravioleta. RESULTADOS E CONCLUSÕES: os resultados foram comparados aos dados da curva de calibração, visando estabelecer a concentração de MMA residual das amostras. Eles permitiram concluir que o nível de MMA residual liberado em solução foi mais elevado durante as primeiras 24 horas, havendo uma tendência à estabilização a partir desse período e que a resina acrílica de uso ortodôntico apresentou níveis mais elevados de MMA em solução do que a de uso protético, em ambas as condições de polimerização empregadas, com presença e ausência de pressão. Além disso, a presença de pressão, durante a polimerização das duas resinas, elevou a concentração de MMA em solução, não havendo, entretanto, efeito da interação entre as marcas das resinas e a presença e ausência de pressão na concentração de MMA em solução, medida ao longo do tempo. Porém, todas as três variáveis (tempo, resina e pressão foram significantes.AIM: Two comercial brands of auto polymerizing acrylic resins (one for orthodontics use, Orto Cril®, and the other for prosthetics use, Jet® were analyzed concerning the amount of methyl methacrilate (MMA monomer dissolved in solution, processed under and not under

Dehydration and acute weight gain in mixed martial arts fighters before competition.

Science.gov (United States)

Jetton, Adam M; Lawrence, Marcus M; Meucci, Marco; Haines, Tracie L; Collier, Scott R; Morris, David M; Utter, Alan C

2013-05-01

The purpose of this study was to characterize the magnitude of acute weight gain (AWG) and dehydration in mixed martial arts (MMA) fighters before competition. Urinary measures of hydration status and body mass were determined approximately 24 hours before and then again approximately 2 hours before competition in 40 MMA fighters (mean ± SE, age: 25.2 ± 0.65 years, height: 1.77 ± 0.01 m, body mass: 75.8 ± 1.5 kg). The AWG was defined as the amount of body weight the fighters gained in the approximately 22-hour period between the official weigh-in and the actual competition. On average, the MMA fighters gained 3.40 ± 2.2 kg or 4.4% of their body weight in the approximately 22-hour period before competition. Urine specific gravity significantly decreased (p 1.021 immediately before competition indicating significant or serious dehydration. The MMA fighters undergo significant dehydration and fluctuations in body mass (4.4% avg.) in the 24-hour period before competition. Urinary measures of hydration status indicate that a significant proportion of MMA fighters are not successfully rehydrating before competition and subsequently are competing in a dehydrated state. Weight management guidelines to prevent acute dehydration in MMA fighters are warranted to prevent unnecessary adverse health events secondary to dehydration.

DSC法研究MMA／纳米Si3N4体系的聚合过程%STUDY ON POLYMERIZATION PROCESS OF MMA/NANO-SI3N4 BY DSC

Institute of Scientific and Technical Information of China (English)

王小东

2011-01-01

Polymerization process of MMA/nano-Si3N4 was studied by DSC. Effects of polymerization temperature, nano-Si3N4 amount and initator concentration of AIBN on polymerization rate were investigated in this article. The results showed that with the polymerization temperature rising,the rate of polymerization increased;the initiatior concentration could effectually improve the polymerization rate; but with the increasing of nano-Si3N4 amount, the polymerization rate was decreased.%利用差示扫描量热仪（DSC）对MMA／纳米Si3N4体系的聚合过程进行研究，着重考察了聚合温度，纳米Si2N4粉体加入量及引发剂AIBN用量对体系聚合速率的影响．结果表明：升高聚合反应温度，增大引发剂用量，均可使体系的凝胶效应提前出现，聚合速率增大；而纳米Si3N4粉体的加入对体系的聚合起到延缓的作用，且随着加入量的增加，聚合速率逐渐降低．

Antitumour and Antioxidant Activities of Activin in Kidney Tissue of Mouse Bearing Murine Mammary Adenocarcinoma and Exposed to Gamma Radiation

International Nuclear Information System (INIS)

EI-Tahawy, N.A.; Hanafi, N.; Said, U.Z.

2009-01-01

Activin (a grape seed-derived proanthocyanidins extract) possess a broad spectrum of biological, pharmacological and therapeutic activities. The present study performed to investigate the preventive and modulating effects of dietary activin in radiation or murine mammary adenocarcinoma (MMA) induced damage in kidneys of albino mice throughout in vitro and in vivo studies. Activin was orally administered to mice for 5 consecutive days (100 mg/ kg body wt) before and 10 days post tumour inoculation. In irradiated group, animals were exposed to 6 Gy whole body gamma-radiations on the fifth day of tumour inoculation. Biochemical and histopathological studies were investigated. In vitro studies using MMA cells revealed that activin increase non viable tumour cell counts. In vivo studies, either MMA or gamma-irradiation resulted in biochemical, and histopathological changes leading to kidney damage. Biochemical studies revealed that activin treatment significantly restored the elevated activity of lactate dehydrogenase (LDH), ameliorated kidney functions profile, and depressed the levels of tumour markers, also enhanced glutathione content (GSH) and activities of superoxide dismutase (SOD) and catalase (CAT). It also reduced kidney lipid peroxides and improves serum total protein level. Histopathological changes in the kidney tissues were attenuated by activin treatment either in MMA-bearing mice group or irradiation group. Exposure of MMA-bearing mouse to gamma- radiations slightly improves the above mentioned damage. While dual treatment of MMA-bearing mice with activin and subsequence with gamma-radiation exposure was more effective. It could be concluded that activin through its antioxidant properties might attenuate radiation or MMA induced renal damage suggesting that activin may have a potential benefit in enhancing radiotherapy

Effect of plasma homocysteine level and urinary monomethylarsonic acid on the risk of arsenic-associated carotid atherosclerosis

International Nuclear Information System (INIS)

Wu, M.-M.; Chiou, H.-Y.; Hsueh, Y.-M.; Hong, C.-T.; Su, C.-L.; Chang, S.-F.; Huang, W.-L.; Wang, H.-T.; Wang, Y.-H.; Hsieh, Y.-C.; Chen, C.-J.

2006-01-01

Arsenic-contaminated well water has been shown to increase the risk of atherosclerosis. Because of involving S-adenosylmethionine, homocysteine may modify the risk by interfering with the biomethylation of ingested arsenic. In this study, we assessed the effect of plasma homocysteine level and urinary monomethylarsonic acid (MMA V ) on the risk of atherosclerosis associated with arsenic. In total, 163 patients with carotid atherosclerosis and 163 controls were studied. Lifetime cumulative arsenic exposure from well water for study subjects was measured as index of arsenic exposure. Homocysteine level was determined by high-performance liquid chromatography (HPLC). Proportion of MMA V (MMA%) was calculated by dividing with total arsenic species in urine, including arsenite, arsenate, MMA V , and dimethylarsinic acid (DMA V ). Results of multiple linear regression analysis show a positive correlation of plasma homocysteine levels to the cumulative arsenic exposure after controlling for atherosclerosis status and nutritional factors (P < 0.05). This correlation, however, did not change substantially the effect of arsenic exposure on the risk of atherosclerosis as analyzed in a subsequent logistic regression model. Logistic regression analyses also show that elevated plasma homocysteine levels did not confer an independent risk for developing atherosclerosis in the study population. However, the risk of having atherosclerosis was increased to 5.4-fold (95% CI, 2.0-15.0) for the study subjects with high MMA% (≥16.5%) and high homocysteine levels (≥12.7 μmol/l) as compared to those with low MMA% (<9.9%) and low homocysteine levels (<12.7 μmol/l). Elevated homocysteinemia may exacerbate the formation of atherosclerosis related to arsenic exposure in individuals with high levels of MMA% in urine

Structure of Human B12 Trafficking Protein CblD Reveals Molecular Mimicry and Identifies a New Subfamily of Nitro-FMN Reductases.

Science.gov (United States)

Yamada, Kazuhiro; Gherasim, Carmen; Banerjee, Ruma; Koutmos, Markos

2015-12-04

In mammals, B12 (or cobalamin) is an essential cofactor required by methionine synthase and methylmalonyl-CoA mutase. A complex intracellular pathway supports the assimilation of cobalamin into its active cofactor forms and delivery to its target enzymes. MMADHC (the methylmalonic aciduria and homocystinuria type D protein), commonly referred to as CblD, is a key chaperone involved in intracellular cobalamin trafficking, and mutations in CblD cause methylmalonic aciduria and/or homocystinuria. Herein, we report the first crystal structure of the globular C-terminal domain of human CblD, which is sufficient for its interaction with MMADHC (the methylmalonic aciduria and homocystinuria type C protein), or CblC, and for supporting the cytoplasmic cobalamin trafficking pathway. CblD contains an α+β fold that is structurally reminiscent of the nitro-FMN reductase superfamily. Two of the closest structural relatives of CblD are CblC, a multifunctional enzyme important for cobalamin trafficking, and the activation domain of methionine synthase. CblD, CblC, and the activation domain of methionine synthase share several distinguishing features and, together with two recently described corrinoid-dependent reductive dehalogenases, constitute a new subclass within the nitro-FMN reductase superfamily. We demonstrate that CblD enhances oxidation of cob(II)alamin bound to CblC and that disease-causing mutations in CblD impair the kinetics of this reaction. The striking structural similarity of CblD to CblC, believed to be contiguous in the cobalamin trafficking pathway, suggests the co-option of molecular mimicry as a strategy for achieving its function. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Evaluation of percolation rate of bedrock aquifer in coastal area

Energy Technology Data Exchange (ETDEWEB)

Lee, Jeong Hwan; Jung, Hae Ryong; Park, Joo Wan; Yoon, Jeong Hyoun; Cheong, Jae Yeol [Korea Radioactive Waste Agency, Daejeon (Korea, Republic of); Park, Sun Ju [NEXGEO Co. Ltd, Seoul (Korea, Republic of); Jun, Seong Chun [GeoGreen21 Co. Ltd, Seoul (Korea, Republic of)

2016-03-15

Estimation of groundwater hydrologic cycle pattern is one of the most critical issues in sustainable management of groundwater resources in coastal area. This study estimated groundwater percolation by using the water balance methodology and hydrogeological characteristics of land use and soil. Evapotranspiration was computed by using the Thornthwaite method, and surface runoff was determined by using the SCS-CN technique. Groundwater storage change was obtained as 229 mm/a (17.8% of the average annual rainfall, 1286 mm/a), with 693 mm/a (60.1%) of evapotranspiration and 124 mm/a (9.6%) of surface runoff. Rainfall and groundwater storage change was highly correlated, comparing with the relationships between rainfall and evapotranspiration, and between rainfall and surface runoff. This result indicates that groundwater storage change responds more sensitively to precipitation than evapotranspiration and surface runoff.

Evaluation of percolation rate of bedrock aquifer in coastal area

International Nuclear Information System (INIS)

Lee, Jeong Hwan; Jung, Hae Ryong; Park, Joo Wan; Yoon, Jeong Hyoun; Cheong, Jae Yeol; Park, Sun Ju; Jun, Seong Chun

2016-01-01

Estimation of groundwater hydrologic cycle pattern is one of the most critical issues in sustainable management of groundwater resources in coastal area. This study estimated groundwater percolation by using the water balance methodology and hydrogeological characteristics of land use and soil. Evapotranspiration was computed by using the Thornthwaite method, and surface runoff was determined by using the SCS-CN technique. Groundwater storage change was obtained as 229 mm/a (17.8% of the average annual rainfall, 1286 mm/a), with 693 mm/a (60.1%) of evapotranspiration and 124 mm/a (9.6%) of surface runoff. Rainfall and groundwater storage change was highly correlated, comparing with the relationships between rainfall and evapotranspiration, and between rainfall and surface runoff. This result indicates that groundwater storage change responds more sensitively to precipitation than evapotranspiration and surface runoff

The human serum metabolome of vitamin B-12 deficiency and repletion, and associations with neurological function

Science.gov (United States)

We characterize the human serum metabolome in sub-clinical vitamin B-12 (B-12) deficiency and repletion. A pre-post treatment study provided one injection of 10 mg B-12 to 27 community-dwelling elderly Chileans with B-12 deficiency evaluated with serum B-12, plasma homocysteine, methylmalonic acid a...

Risk factors and birth prevalence of birth defects and inborn errors of ...

African Journals Online (AJOL)

raoul

2011-02-23

Feb 23, 2011 ... methylmalonic aciduria, and maple syrup urine disease (MSUD) had their diagnoses confirmed by enzyme assay. The diagnosis of all ... Personal information like date of birth, sex, area of residence, mother's age at birth, father's age, order of birth, birth weight, gestational age on birth, medical history and ...

Breathing zone concentrations of methylmethacrylate monomer during joint replacement operations

DEFF Research Database (Denmark)

Darre, E; Jørgensen, L G; Vedel, P

1992-01-01

By use of a methylmethacrylate (MMA) Dräger tube and bellow bump, the breathing zone concentrations of MMA monomer were measured for the operating surgeon during cementation of the components of hip and knee joint prostheses. The highest recordings (50-100 p.p.m.) were encountered during cementat...... cementation of the acetabular cups with conventional polymethylmethacrylate cement. Such exposure could be eliminated by the use of personal protection equipment, local punctual field suction or change to a MMA/n-decylmethacrylate/isobornylmethacrylate bone cement....

Investigation of Complexation of Linear Poly(N-vinyl-2-pyrrolidone) with Poly(methacrylic acid-co-methyl methacrylate) Gel

OpenAIRE

Liu, Guoqin; Yan, Guojin; Zou, Wenjun; Li, Zhengxin

2011-01-01

The contraction of poly(methacrylic acid-co-methyl methacrylate) (P(MAA-co-MMA)) gel induced by complexation with linear poly(N-vinyl-2-pyrrolidone) (PVP) is quite different from that of poly(acrylic acid) (PAA) or poly(methacrylic acid) (PMAA) gel. It was found that the concentration of PVP has a strong effect on the complexation with P(MAA-co-MMA) gel. When PVP was introduced into the P(MAA-co-MMA) network, its dynamic mechanic properties vary greatly between complexed and uncomplexed netwo...

Analysis of Gel Permeation Chromatography From Irradiation Copolymer Grafting of Methylmethacrylate on to Natural Rubber

International Nuclear Information System (INIS)

Hendrana, Sunit; Purwanto, Indratmoko Hari; Karyaningsih, Ipit; Utama, MargaHerwinarni

2004-01-01

Grafting of methyl methacrylate (MMA) onto natural rubber was carried out by γ-irradiation using 60 Co source at dose rate 1 KGy/h and total dose of 5 KGy. Gel permeation chromatography (GPC) was used to analyse the grafting. The GPC's chromatogram, molecular weight and molecular weight distribution data indicate that grafting of MMA onto natural rubber and homo polymerization of MMA are the reaction mostly occurs. Meanwhile, the presence of natural rubber radical with a chain end natural rubber radical affect the PMMA homopolymer occurred

On the motion od the Caribbean relative to South-America: New results from GPS geodesy 1999-2012

Science.gov (United States)

De La Rosa, R.; Marquez, J.; Bravo, M.; Madriz, Y.; Mencin, D.; Wesnousky, S. G.; Molnar, P. H.; Bilham, R.; Perez, O. J.

2013-05-01

Our previous (1994-2006) collaborative GPS studies in southern Caribbean and northern South-America (SA) show that along its southern boundary in north-central and northeastern Venezuela (Vzla) the Caribbean plate (CP) slips easterly at ~20 mm/a relative to SA, and that in northwestern South-America slip-partitioning takes place resulting in 12 mm/a of dextral motion across the Venezuelan Andes, ~6 mm/a of which occur along the main trace of the NE-trending Bocono fault, and the rest is taken up by SE-subduction of the CP beneath northwestern SA. A series of new velocity vectors obtained in the region from GPS geodesy in 1999-2012 and their corresponding elastic modelings shows that in north-central Vzla part (~3 mm/a) of the C-SA relative dextral shear is taken up by the east-trending continental La Victoria fault, which runs ~50 kms south of San Sebastian fault off-shore and is sub-parallel to it, the later taken up the rest of the motion. The velocity we find for Aruba Is (~20 mm/y due ~east) is consistent with the motion predicted by the Euler pole (61,9° N; 75,7 °W; ω = 0,229 °/Ma) we previously calculated to describe the C-SA relative plate motion. New velocity vectors obtained across the Venezuelan Andes are consistent with a modeled surface velocity due to 12 mm/a of dextral shear below a locking depth of 14 km on one or more vertical N50°E striking faults located within the 100-km wide Andean ranges. The Andes also show a horizontal convergence rate of 2 to 4 mm/a suggesting an uplift rate of ~1.7 mm/a if thrust motion takes place on shallowly dipping faults parallel to the Andes.

A study on radiation-resistance of PIC (polymer-impregnated concrete) for container of conditioning and disposal of low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Ishizaki, Kanjiro; Sudoh, Giichi; Araki, Kunio; Kasahara, Yuko.

1983-01-01

The radiation-resistance of PIC with test piece was evaluated by irradiation of gamma-rays. All the test pieces had JIS mortar size of 4 x 4 x 16 cm. JIS mortar and concrete were used as specimens. The maximum aggregate size of concrete was 10 mm. The specimens impregnated by MMA (methylmethacrylate) monomer and solution of 10% of PSt (polystyrene) in MMA monomer (MMA .PSt) were polymerized by irradiating for 5 hr at the dose rate of 1 MR (1 x 10 6 Roentgen)/hr. PIC specimens were exposed up to maximum 1000 MR to 60 Co gamma-rays in air and under water which simulate shallow land disposal and deep sea dumping conditions, respectively. The lowering of strength of the PIC exposed to gamma-rays under water was larger than that of the PIC in air. The improving effect of the added PSt on the radiation-resistance was observed. It was observed that the 50 MR-irradiated MMA.PSt-PIC under water, which had the residual compressive strength of 85%, was resistant to gamma-rays. When this residual strength was regarded as a limit of radiation-resistance in air, the limit of MMA and MMA.PSt-PIC were approximately 25 MR and 150 MR, respectively. The lowering of strength was mainly due to the deterioration of MMA polymer in PIC. The total exposure dose for PIC-container was estimated by assuming the conditions about the packaged radioactive wastes, dose rate, container and so on. The total exposure dose on PIC-container for 100 years became roughly 1.25 MR. Therefore, it is estimated that the PIC-containers for conditioning and disposal of low and intermediate level radioactive wastes have a sufficient resistance to radiation arising from wastes. (author)

Cortical Astrocytes Acutely Exposed to the Monomethylarsonous Acid (MMAIII) Show Increased Pro-inflammatory Cytokines Gene Expression that is Consistent with APP and BACE-1: Over-expression.

Science.gov (United States)

Escudero-Lourdes, C; Uresti-Rivera, E E; Oliva-González, C; Torres-Ramos, M A; Aguirre-Bañuelos, P; Gandolfi, A J

2016-10-01

Long-term exposure to inorganic arsenic (iAs) through drinking water has been associated with cognitive impairment in children and adults; however, the related pathogenic mechanisms have not been completely described. Increased or chronic inflammation in the brain is linked to impaired cognition and neurodegeneration; iAs induces strong inflammatory responses in several cells, but this effect has been poorly evaluated in central nervous system (CNS) cells. Because astrocytes are the most abundant cells in the CNS and play a critical role in brain homeostasis, including regulation of the inflammatory response, any functional impairment in them can be deleterious for the brain. We propose that iAs could induce cognitive impairment through inflammatory response activation in astrocytes. In the present work, rat cortical astrocytes were acutely exposed in vitro to the monomethylated metabolite of iAs (MMA III ), which accumulates in glial cells without compromising cell viability. MMA III LD 50 in astrocytes was 10.52 μM, however, exposure to sub-toxic MMA III concentrations (50-1000 nM) significantly increased IL-1β, IL-6, TNF-α, COX-2, and MIF-1 gene expression. These effects were consistent with amyloid precursor protein (APP) and β-secretase (BACE-1) increased gene expression, mainly for those MMA III concentrations that also induced TNF-α over-expression. Other effects of MMA III on cortical astrocytes included increased proliferative and metabolic activity. All tested MMA III concentrations led to an inhibition of intracellular lactate dehydrogenase (LDH) activity. Results suggest that MMA III induces important metabolic and functional changes in astrocytes that may affect brain homeostasis and that inflammation may play a major role in cognitive impairment-related pathogenicity in As-exposed populations.

Evaluation of AirPollution Control fromViewpoints of Cost- Benefit Analysis in a Tile Industry

Directory of Open Access Journals (Sweden)

SJ Shahtaheri

2006-04-01

Full Text Available Background and Aims:Methyl Methacrylate (MMA which is known as a long, skin and eyeirritant is the most common form of acrylic plastic used in dental laboratories. The aims of thisstudy were to evaluate dental technicians, exposure to MMAand to assess their health with a focuson respiratory and dermal symptoms.Method: Exposure to MMA, total dust and health symptoms were investigated in 20 dentallaboratories located in Tehran, Iran. Time weighted average (TWA of MMA and peakconcentrations were determined , using XAD-2 tubes followed by GC-ID analysis. Total dustwere evaluated gravimetrically. Health symptoms were asked using a questionnaire.Results :The TWAfor technicians with direct and indirect exposure to MMAwere 327.28 + 79.42and 282.9 + 41.84 mg/m3, respectively. Peak concentration of MMA for those technicians were337.0 + 36.81 and 328.88 + 45.40 mg/m3, respectively. There were no significant differencesbetween TWAof MMAand peak concentration in different weakly workdays; low ever, within -day variations were observed (P<0.05. TWAof MMA and peak concentration correlation withthe laboratory volume were 0.61- 0.65, Dust exposure of technicians was 2.35 + 2.70 mg/m3.Cough and Skin dryness were the common health symptoms. Smoking and asbestos exposurehistory were factors influencing cough prevalence (P<0.005.Conclusion:It is concluded that the current short - Term Exposure Limit (STEL is not low enoughto protect technicians against the adverse effects caused by MMA.

High temperature initiator-free RAFT polymerization of methyl methacrylate in a microwave reactor

NARCIS (Netherlands)

Paulus, R.M.; Becer, C.R.; Hoogenboom, R.; Schubert, U.S.

2009-01-01

The reversible additionfragmentation chain transfer (RAFT) polymerization of methyl methacrylate (MMA) was investigated under microwave irradiation. At first, a comparison was made between microwave and thermal heating for the RAFT polymerization of MMA with azobis(isobutyronitrile) (AIBN) as

Synthesis, Characterization and Application of A Novel Carbon Bridged Half-metallocene Chromium Catalyst for Methyl Methacrylate Polymerization

Institute of Scientific and Technical Information of China (English)

CHENG Zhengzai; GONG Kai; WANG Yang; ZHOU Xue; ZHANG Weixing; LI Yin; SUN Junquan; LI Wenbing

2014-01-01

A new carbon bridged cyclopentadienyl chromium complex of the type [(C5H4)C(CH3)2 CH2(C5H4N)]CrCl2 was prepared by treatment of CrCl3•(THF)3 in THF solution with the lithium salt of ligand containing cyclopentadienyl and pyridyl groups. The chromium complex was characterized by 1H NMR and elemental analysis(EA), and the crystal structure was determined by X-ray diffraction analysis. Activated by Al(i-Bu)3, the chromium complex displayed a very high activity for methyl methacrylate (MMA) polymerization. After 24 hours,more than 95.5%MMA was converted to polymethyl methacrylate (PMMA) with a viscosity average molecular weight (Wη) of 416000 g•mol-1 at 60℃for MMA/Al(i-Bu)3/chromium catalyst molar ratio of up to 2000:20:1. Effects of temperature, molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The high conversion of MMA and high molecular weight of PMMA with narrow molecular weight distribution is caused by the unique stable active site formed by the new chromium complex and aluminum cocatalyst.

Upgrading of lignocellulosic biorefinery to value-added chemicals: Sustainability and economics of bioethanol-derivatives

DEFF Research Database (Denmark)

Cheali, Peam; Posada, John A.; Gernaey, Krist

2015-01-01

with a sustainability assessment method is used as evaluation tool. First, an existing superstructure representing the lignocellulosic biorefinery design network is extended to include the options for catalytic conversion of bioethanol to value-added derivatives. Second, the optimization problem for process upgrade...... of operating profit for biorefineries producing bioethanol-derived chemicals (247 MM$/a and 241 MM$/a for diethyl ether and 1,3-butadiene, respectively). Second, the optimal designs for upgrading bioethanol (i.e. production of 1,3-butadiene and diethyl ether) performed also better with respect...... to sustainability compared with the petroleum-based processes. In both cases, the effects of the market price uncertainties were also analyzed by performing quantitative economic risk analysis and presented a significant risk of investment for a lignocellulosic biorefinery (12 MM$/a and 92 MM$/a for diethyl ether...

An analytic Pade-motivated QCD coupling

International Nuclear Information System (INIS)

Martinez, H. E.; Cvetic, G.

2010-01-01

We consider a modification of the Minimal Analytic (MA) coupling of Shirkov and Solovtsov. This modified MA (mMA) coupling reflects the desired analytic properties of the space-like observables. We show that an approximation by Dirac deltas of its discontinuity function ρ is equivalent to a Pade(rational) approximation of the mMA coupling that keeps its analytic structure. We propose a modification to mMA that, as preliminary results indicate, could be an improvement in the evaluation of low-energy observables compared with other analytic couplings.

Fetal blood gas values during fetoscopic myelomeningocele repair performed under carbon dioxide insufflation.

Science.gov (United States)

Baschat, Ahmet A; Ahn, Edward S; Murphy, Jamie; Miller, Jena L

2018-05-10

Fetoscopic myelomeningocele (MMC) repair is performed with intrauterine carbon dioxide (CO 2 ) insufflation. While lamb experiments have shown significant fetal acidemia following CO 2 insufflation corresponding information for human pregnancies is not available. We performed umbilical venous cord blood sampling in three patients during fetoscopic MMC repair at 25+1, 25+3 and 24+1 weeks gestation. Fetal venous pH at the beginning of CO 2 insufflation were 7.36, 7.46 and 7.37; repeat values were 7.28, 7.35, 7.36 after 181, 159 and 149 minutes respectively. The partial pressure of oxygen and carbon dioxide was maintained in the normal range at these times and pH decrease was less in patient 3 receiving humidified CO2 insufflation. Our observations suggest that in contrast to sheep experiments, CO2 insufflation during fetoscopic myelomeningocele repair does not cause fetal acidemia. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Physicians' Plan for a healthy Minnesota. The MMA proposal for health care reform. The report of the Minnesota Medical Association Health Care Reform Task Force.

Science.gov (United States)

2005-03-01

The health care system in the United States, according to some, is on the verge of imploding. The rapidly rising cost of services is causing more and more Minnesotans to forego needed care. At the same time, the increasing costs are placing additional pressure on families, businesses, and state and local government budgets. The Minnesota Medical Association's (MMA) Health Care Reform Task Force has proposed a bold new approach that seeks to ensure affordable health care for all Minnesotans. The proposal is a roadmap to provide all Minnesotans with affordable insurance for essential health care services. In creating this plan, the task force strove to achieve three common reform goals: expand access to care, improve quality, and control costs. To achieve those ends, it has proposed a model built on four key features: (1) A strong public health system, (2) A reformed insurance market that delivers universal coverage, (3) A reformed health care delivery market that creates incentives for increasing value, (4) Systems that fully support the delivery of high-quality care. The task force believes that these elements will provide the foundation for a system that serves everyone and allows Minnesotans to purchase better health care at a relatively lower price. Why health care reform again? The average annual cost of health care for an average Minnesota household is about 11,000 dollars--an amount that's projected to double by 2010, if current trends continue. Real wages are not growing fast enough to absorb such cost increases. If unabated, these trends portend a reduction in access to and quality of care, and a heavier economic burden on individuals, employers, and the government. Furthermore, Minnesota and the United States are not getting the best value for their health care dollars. The United States spends 50 percent more per capita than any other country on health care but lags far behind other countries in the health measures of its population.

A novel process for ultrasound-induced radical polymerization in CO2-expanded fluids

NARCIS (Netherlands)

Kemmere, M.F.; Kuijpers, M.W.A.; Prickaerts, R.M.H.; Keurentjes, J.T.F.

2005-01-01

A strong viscosity increase upon polymerization hinders cavitation and subsequent radical formation during an ultrasound-induced bulk polymerization. In this work, ultrasound-induced radical polymerizations of methyl methacrylate (MMA) have been performed in CO2-expanded MMA in order to reduce the

STUDIES ON RADICAL POLYMERIZATION OF METHYL METHACRYLATE INITIATED WITH ORGANIC PEROXIDE-AMINE SYSTEMS

Institute of Scientific and Technical Information of China (English)

QIU Kunyuan; SHUI Li; FENG Xinde

1984-01-01

Radical polymerization of methyl methacrylate (MMA) initiated with various diacyl peroxideamine systems was studied. Benzoyl peroxide (BPO) and lauroyl peroxide (LPO) were used as diacyl peroxide component, N,N-dimethyl aniline (DMA) and its para substituted derivatives, i.e., N,N-dimethyl-p-toluidine (DMT), p-hydroxymethyl-N,N-dimethyl aniline (HDMA), p-nitro-N,N-dimethyl aniline (NDMA) and p-dimethylamino benzaldehyde (DMAB) were used as amine components. It was found that the peroxide-DMT systems give higher rates of bulk polymerization Rp of MMA than the organic hydroperoxide-DMT systems with the following descending order BPO-DMT＞LPO-DMT＞CHP (cumene hydroperoxide)-DMT＞TBH (tert-butyl hydroperoxide)-DMT.The aromatic tertiary amines possess obvious structural effect on the Rp values in the diacyl peroxideamine system. The overall activation energy of MMA polymerization was determined and the kinetics of polymerization of MMA initiated with BPO-DMT system was investigated.

"It is what it is": masculinity, homosexuality, and inclusive discourse in mixed martial arts.

Science.gov (United States)

Channon, Alex; Matthews, Christopher R

2015-01-01

In this article we make use of inclusive masculinity theory to explore online media representations of male homosexuality and masculinity within the increasingly popular combat sport of mixed martial arts (MMA). Adopting a case-study approach, we discuss narratives constructed around one aspirational male MMA fighter, Dakota Cochrane, whose history of having participated in gay pornography became a major talking point on a number of MMA discussion/community Web sites during early 2012. While these narratives attempted to discursively rescue Cochrane's supposedly threatened masculinity, highlighting both his "true" heterosexuality and his prodigious fighting abilities, they also simultaneously celebrated the acceptance of homosexual men within the sport that Cochrane's case implied. Thus, we suggest that these media representations of homosexuality and masculinity within MMA are indicative of declining cultural homophobia and homohysteria and an inclusive vision of masculinity, as previously described by proponents of inclusive masculinity theory.

An assessment of predictive value of the biophysical profile in women with preeclampsia using data from the fullPIERS database.

Science.gov (United States)

Payne, Beth A; Kyle, Phillipa M; Lim, Kenneth; Lisonkova, Sarka; Magee, Laura A; Pullar, Barbra; Qu, Ziguang; von Dadelszen, Peter

2013-07-01

Pre-eclampsia is associated with increased risk to both the mother and fetus. Effective monitoring of the fetal condition is essential to the management of women with pre-eclampsia. The biophysical profile (BPP) is one monitoring tool available to clinicians. To compare the BPP test with cardiotocography/non-stress test (CTG/NST) alone for their ability to predict fetal acidemia at birth or a composite adverse perinatal outcome among women with preeclampsia and to estimate the effect of BPP assessment on mode of delivery and birth outcome. Secondary analysis of a prospective cohort of women with preeclampsia. The predictive ability of the tests was assessed based on sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-). Women assessed with the BPP were compared with matched controls not assessed with the BPP to determine the odds of Cesarean delivery or adverse perinatal outcomes after adjustment for potential confounders. Five out of 89 women (5.6%) had an abnormal BPP; 18 out of 89 (20.2%) had an abnormal CTG/NST. Fetal acidemia was diagnosed in 13 fetuses (14.6%); composite adverse perinatal outcome in 68 fetuses/infants (76.4%). Both tests had relatively poor predictive performance for both outcomes (LR+ between 2.50 and 3.90 and LR- between 0.64 and 0.93). Assessment with the BPP was positively associated with fetal acidemia (adjusted OR 4.84; 95% CI 1.33-17.66). The BPP and CTG/NST alone were poor predictors of perinatal outcome in this cohort; multiple tests should be considered when assessing fetal risk in women with preeclampsia. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Intestinal Malabsorption in Long-Term Survivors of Cervical Cancer Treated With Radiotherapy

International Nuclear Information System (INIS)

Vistad, Ingvild; Kristensen, Gunnar B.; Fossa, Sophie D.; Dahl, Alv A.; Morkrid, Lars

2009-01-01

Purpose: The aim of this cross-sectional study is to investigate the associations between pelvic radiotherapy (RT) and markers of intestinal absorption in cervical cancer survivors (CCSs). We compared patient data with normative data from a reference population and explored the associations between cobalamin status and clinically significant diarrhea and depression. Methods and Materials: Fifty-five CCSs treated with RT in 1994-1999 were included in 2005 in a follow-up questionnaire study exploring physical and psychological symptoms. Blood tests, including serum (S)-vitamin B 12, S-methylmalonic acid, S-folate, erythrocyte-folate, and plasma homocysteine, were analyzed. Differences in median values between CCSs and reference populations were evaluated by using Wilcoxon tests. Associations between variables were examined by means of multiple regression analyses. Results: Median S-vitamin B 12 level was significantly lower and median S-methylmalonic acid level was significantly higher in CCSs compared with the reference population (p 12 level is recommended, and regular intake of cobalamin should be considered in CCSs treated with RT

Hyperammonaemic encephalopathy secondary to selective cobalamin deficiency in a juvenile Border collie.

Science.gov (United States)

Battersby, I A; Giger, U; Hall, E J

2005-07-01

An eight-month-old Border collie was presented with anorexia, cachexia, failure to thrive and stupor. Laboratory tests demonstrated a mild anaemia, neutropenia, proteinuria and hyperammonaemia. Serum bile acid concentrations were normal, but an ammonia tolerance test (ATT) was abnormal. The dog responded to symptomatic therapy for hepatoencephalopathy. When a low serum cobalamin (vitamin B12) concentration and methylmalonic aciduria were noted, the dog was given a supplement of parenteral cobalamin. Two weeks later, a repeat ATT was normal. Cobalamin supplementation was continued every two weeks, and all clinical signs, except for proteinuria, resolved despite withdrawing all therapy for hepatoencephalopathy. A presumptive diagnosis of hereditary selective cobalamin malabsorption was made, based on the young age, Border collie breed, low serum cobalamin concentration and methylmalonic aciduria. Although hereditary selective cobalamin malabsorption in Border collies, giant schnauzers, Australian shepherd dogs and beagles has previously been reported in North America, to the authors' knowledge this is the first report of the condition in the UK and the first to document an abnormal ATT in a cobalamin-deficient dog.

Forehead Augmentation with a Methyl Methacrylate Onlay Implant Using an Injection-Molding Technique

Directory of Open Access Journals (Sweden)

Dong Kwon Park

2013-09-01

Full Text Available BackgroundThe forehead, which occupies about one third of the face, is one of the major determinants of a feminine or masculine look. Various methods have been used for the augmentation of the forehead using autologous fat grafts or alloplastic materials. Methylmethacrylate (MMA is the most appropriate material for augmentation of the forehead, and we have used an injection-molding technique with MMA to achieve satisfactory results.MethodsUnder local anesthesia with intravenous (IV sedation, an incision was made on the scalp and a meticulous and delicate subperiosteal dissection was then performed. MMA monomers and polymers were mixed, the dough was injected into the space created, and manual molding was performed along with direct inspection. This surgery was indicated for patients who wanted to correct an unattractive appearance by forehead augmentation. Every patient in this study visited our clinics 3 months after surgery to evaluate the results. We judged the postoperative results in terms of re-operation rates caused by the dissatisfaction of the patients and complications.ResultsDuring a 13-year period, 516 patients underwent forehead augmentation with MMA. With the injection-molding technique, the inner surface of the MMA implant is positioned close to the underlying frontal bone, which minimizes the gap between the implant and bone. The borders of the implant should be tapered sufficiently until no longer palpable or visible. Only 28 patients (5.4% underwent a re-operation due to an undesirable postoperative appearance.ConclusionsThe injection-molding technique using MMA is a simple, safe, and ideal method for the augmentation of the forehead.

Individual differences in arsenic metabolism and lung cancer in a case-control study in Cordoba, Argentina

International Nuclear Information System (INIS)

Steinmaus, Craig; Yuan Yan; Kalman, Dave; Rey, Omar A.; Skibola, Christine F.; Dauphine, Dave; Basu, Anamika; Porter, Kristin E.; Hubbard, Alan; Bates, Michael N.; Smith, Martyn T.; Smith, Allan H.

2010-01-01

In humans, ingested inorganic arsenic is metabolized to monomethylarsenic (MMA) then to dimethylarsenic (DMA), although in most people this process is not complete. Previous studies have identified associations between the proportion of urinary MMA (%MMA) and increased risks of several arsenic-related diseases, although none of these reported on lung cancer. In this study, urinary arsenic metabolites were assessed in 45 lung cancer cases and 75 controls from arsenic-exposed areas in Cordoba, Argentina. Folate has also been linked to arsenic-disease susceptibility, thus an exploratory assessment of associations between single nucleotide polymorphisms in folate metabolizing genes, arsenic methylation, and lung cancer was also conducted. In analyses limited to subjects with metabolite concentrations above detection limits, the mean %MMA was higher in cases than in controls (17.5% versus 14.3%, p = 0.01). The lung cancer odds ratio for subjects with %MMA in the upper tertile compared to those in the lowest tertile was 3.09 (95% CI, 1.08-8.81). Although the study size was too small for a definitive conclusion, there was an indication that lung cancer risks might be highest in those with a high %MMA who also carried cystathionine β-synthase (CBS) rs234709 and rs4920037 variant alleles. This study is the first to report an association between individual differences in arsenic metabolism and lung cancer, a leading cause of arsenic-related mortality. These results add to the increasing body of evidence that variation in arsenic metabolism plays an important role in arsenic-disease susceptibility.

Towards a Determination of the Physiological Characteristics Distinguishing Successful Mixed Martial Arts Athletes: A Systematic Review of Combat Sport Literature.

Science.gov (United States)

James, Lachlan P; Haff, G Gregory; Kelly, Vincent G; Beckman, Emma M

2016-10-01

Mixed martial arts (MMA) is a combat sport underpinned by techniques from other combat disciplines, in addition to strategies unique to the sport itself. These sports can be divided into two distinct categories (grappling or striking) based on differing technical demands. Uniquely, MMA combines both methods of combat and therefore appears to be physiologically complex requiring a spectrum of mechanical and metabolic qualities to drive performance. However, little is known about the physiological characteristics that distinguish higher- from lower-level MMA athletes. Such information provides guidance for training interventions, performance testing and talent identification. Furthermore, while MMA incorporates techniques from both grappling and striking sports, it is unknown precisely how these disciplines differ physiologically. Understanding the relationship between higher-level competitors in grappling and striking combat sports can provide further insight into the development of the optimal performance profile of a higher-level MMA athlete. This article aims to analyse the scientific literature on MMA and the primary combat sports underpinning it to determine the physiological adaptations that distinguish superior competitors, with a view to defining the optimal physiological profile for higher-level MMA performance. Furthermore, this article will explore the differences in these capabilities between grappling- and striking-based combat sports in the context of MMA. A literature search was undertaken via PubMed, Web of Science, SportDiscus and Google Scholar. The following sports were included for systematic review based on their relevance to MMA: mixed martial arts, boxing, Brazilian jiu-jitsu, judo, karate, kickboxing, Muay Thai and wrestling. The inclusion criteria allowed studies that compared athletes of differing competition levels in the same sport using a physiological performance measure. Only male, adult (aged 17-40 years), able-bodied competitors

Light microscopic identification and semiquantification of polyethylene particles in methylmethacrylate and paraffin-embedded experimental bone implant specimens

DEFF Research Database (Denmark)

Rahbek, O; Kold, S; Overgaard, S

2005-01-01

The aim of this study was to evaluate the identification of polyethylene (PE) particles in relatively thick methylmethacrylate (MMA) sections widely used in bone implant research. The sensitivity and specificity were compared between decalcified paraffin-embedded oil red O (ORO) stained and MMA-e...

Olefin copolymerization via controlled radical polymerization : copolymerization of methyl methacrylate and 1-octene

NARCIS (Netherlands)

Venkatesh, R.; Klumperman, B.

2004-01-01

The atom transfer radical (co)polymerization (ATRP) of methyl methacrylate (MMA) with 1-octene was investigated. Well controlled homopolymer of MMA was obtained with 2,2,2-trichoroethanol (TCE) and p-toluenesulfonyl chloride (pTsCl), although, uncontrolled copolymerization occurred when pTsCl was

Operative neurosurgery. Personal view and historical backgrounds. (9) Moyamoya angiopathy (MMA). Past history and status presens

International Nuclear Information System (INIS)

Yonekawa, Yasuhiro

2012-01-01

The second international meeting on the Moyamoya angiopathy (MMA) was held in mid. July 2011 at the children's hospital Zurich by Frau PD Dr.Khan and Prof.Meuli. On this occasion I was asked to give a survey of this disease, so the following points were presented and discussed: Who was the person who discovered this disease. How has the Research Committee of the Ministry of Health and Welfare, Japan (RCMHWJ) contributed to clarify the epidemiology, etiology, pathophysiology and treatments. What is the current situation in foreign countries especially Euroamerican to date on these topics. How the treatment technique developed and who did the initial revascularization procedures for the first. Update of the disease. Established view; discovery of the disease by Tekeuchi and Shimizu in 1955 could have been called somewhat into question as they described neither abnormal vasculature nor transdural anastomosis. Kudo who described ''spontaneous occlusion of the circle of Willis'' more precisely, but seemed to have thought that the occlusion site of the internal carotid artery (ICA) is around the origin of the ophthalmic artery. Suzuki and Takaku who coined the name Moyamoya disease (MMD) in 1969 and described 6 stages of progression on the basis of observation on 20 cases. The RCMHWJ founded in 1977 has contributed to clarifying the epidemiology, pathophysiology, treatment and etiology by interdisciplinary cooperative study having some epoch making events especially; by setting the guide lines -diagnostic criteria of the disease at the end of 1970, applying MRI and MR angiography (MRA) at the beginning of 1990 for the diagnosis instead of angiography used until then. By finding and focusing, therefore, on the cases of asymptomatic or oligosymptomatic presentation around the middle of 2000, which have almost doubled or tripled in incidence and/or prevalence and also changed the age distribution with the higher peak for adult cases. Achievements of research for the

Investigation of Complexation of Linear Poly(N-vinyl-2-pyrrolidone with Poly(methacrylic acid-co-methyl methacrylate Gel

Directory of Open Access Journals (Sweden)

Guoqin Liu

2011-01-01

Full Text Available The contraction of poly(methacrylic acid-co-methyl methacrylate (P(MAA-co-MMA gel induced by complexation with linear poly(N-vinyl-2-pyrrolidone (PVP is quite different from that of poly(acrylic acid (PAA or poly(methacrylic acid (PMAA gel. It was found that the concentration of PVP has a strong effect on the complexation with P(MAA-co-MMA gel. When PVP was introduced into the P(MAA-co-MMA network, its dynamic mechanic properties vary greatly between complexed and uncomplexed networks. It had the following results: (1 the higher modulus ratio; (2 a slight contraction of gel.

A Historical Overview of Mixed Martial Arts in China

Directory of Open Access Journals (Sweden)

William Acevedo

2012-05-01

Full Text Available Mixed martial arts (MMA has become one of the fastest-growing combat sports in the twenty-first century, drawing millions of Pay-Per-View spectators since the inception of the Ultimate Fighting Championship (UFC in 1993. Popular conceptions have credited the creation of MMA to Bruce Lee, a Chinese-American actor and martial artist who became an icon in the 1970s and who is still considered by many as a revolutionary figure in the field. This paper will present, in chronological order, examples of ancient Chinese martial arts concepts preceding the creation of modern MMA.

The polymorphism of dopamine receptor D4 (DRD4) and dopamine transporter (DAT) genes in the men with antisocial behaviour and mixed martial arts fighters.

Science.gov (United States)

Cherepkova, Elena V; Maksimov, Vladimir N; Kushnarev, Alexandr P; Shakhmatov, Igor I; Aftanas, Lyubomir I

2017-09-12

Variable-number tandem repeat (VNTR) polymorphisms of DRD4 and DAT genes were studied in the Russian and Chechen men convicted of crimes, and two control groups comprised of the MMA fighters and a sample of general population. A group of MMA fighters included only the subjects without history of antisocial behaviour. DNA was isolated by phenol-chloroform extraction from the blood. Genotyping VNTR polymorphisms of the DRD4 and DAT genes were performed by PCR on published methods. Among those convicted of felonies and most grave crimes, carriers of DRD4 long alleles are found more frequently, similarly to the cohort of MMA fighters (lacking criminal record in both paternal lines). The 9/9 DAT genotype carriers are more frequently encountered among the habitual offenders. A frequency of the combination of the DRD4 genotype 4/7 and DAT genotype 10/10 is clearly higher among the convicts of violent crimes and the MMA fighters. One can speculate the presence of a 'controlled aggression' without a predisposition to pathological violence in the MMA fighters. Our study supports the hypothesis of genetic predisposition to different variants of extreme behaviour mediated by genetic determinants involved in the functioning of neuromediator systems including those controlling dopamine pathways.

Construction of wettability gradient surface on copper substrate by controlled hydrolysis of poly(methyl methacrylate–butyl acrylate) films

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yong, E-mail: Yong.Z@mail.scut.edu.cn [Guangzhou Panyu Polytechnic, Guangzhou 511483 (China); Cheng, Jiang; Yang, Zhuo-ru [School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640 (China)

2014-10-01

We report a gradient wettability surface on copper slide prepared by a simple controlled ester group hydrolysis procedure of poly(methyl methacrylate–butyl acrylate) [P (MMA-BA)] films coated on the copper substrate. In the method, sodium hydroxide solutions are selected to prepare surface gradient wettability on P (MMA-BA) films. The P (MMA-BA) copolymers with different MMA contents are first synthesized by a conventional free atom radical solution polymerization method. The transfer of surface chemical composition from the ester group to acid salt is achieved by hydrolysis in NaOH solution. The effects of different concentrations of NaOH solution and reaction times on the physicochemical properties of the resulting surfaces are studied. The field-emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) results show that the varying concentration along the substrate length is only attributed to the hydrolysis reaction of ester groups. The hydrolysis causes insignificant change on the morphology of the original film on the copper substrate. In addition, it is found that the MMA copolymer content has a significant influence on the concentration of ester groups on the outermost surface and thus important for forming the slope gradients.

Renal and cerebral responses to hypoxemia in the ovine fetus

NARCIS (Netherlands)

Mild to moderate hypoxemia without major changes in pH and pCO(2) does not reduce fetal renal blood flow and fetal urine production rate. Other factors such as acidemia, hypercapnia or changes in lung liquid production or fetal swallowing are candidates for the reduced amniotic fluid in the growth

Usefulness of interventional embolization of the middle meningeal artery for recurrent chronic subdural hematoma: Five cases and a review of the literature

Science.gov (United States)

Yamauchi, Shigeru; Ikeda, Hidetoshi; Tsubota, Nobuyuki; Furukawa, Hironori; Maeda, Daisuke; Kondo, Kimito; Nishio, Akimasa

2015-01-01

Purpose Although several strategies against recurrent chronic subdural hematoma (CSDH) have been proposed, no consensus has been established. Recently, middle meningeal artery (MMA) embolization has been proposed as radical treatment for recurrent CSDH. We wanted to estimate the usefulness of MMA embolization for recurrent CSDH. Methods From February 2012 to June 2013, 110 patients with CSDH underwent single burr-hole surgery with irrigation and drainage. Among these patients, 13 showed recurrent hematoma formation and were retreated surgically. Furthermore, repeated recurrence of CSDH was observed in six patients. Five of these six patients underwent middle meningeal artery (MMA) embolization with polyvinyl alcohol particles. All five patients with interventional treatment were observed for four to 60 weeks. Results No more recurrence of CSDH was observed in any of the patients. During the follow-up period, no patients suffered from any side effects or complications from the interventional treatment. Conclusion MMA embolization with careful attention paid to the procedure might be a treatment of choice for recurrent CSDH. PMID:26015518

Preparation and Characterization of Acrylic Primer for Concrete Substrate Application

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El-Sayed Negim

2016-01-01

Full Text Available This study dealt with the properties of acrylic primer for concrete substrate using acrylic syrup, made from a methyl methacrylate monomer solution of terpolymers. Terpolymer systems consisting of methyl methacrylate (MMA, 2-ethylhexyl acrylate (2-EHA, and methacrylic acid (MAA with different chemical composition ratios of MMA and 2-EHA were synthesized through bulk polymerization using azobisisobutyronitrile (AIBN as initiator. The terpolymer composition is characterized by FTIR, 1H NMR, DSC, TGA, and SEM. The glass transition temperature and the thermal stability increased with increasing amounts of MMA in the terpolymer backbone. The effect of chemical composition of terpolymers on physicomechanical properties of primer films was investigated. However, increasing the amount of MMA in terpolymer backbone increased tensile and contact angle of primer films while elongation at break, water absorption, and bond strength are decreased. In particular, the primer syrup containing 65% 2-EHA has good bonding strength with concrete substrate around 1.1 MPa.

One-pot synthesis of zeolitic imidazolate framework-8/poly (methyl methacrylate-ethyleneglycol dimethacrylate) monolith coating for stir bar sorptive extraction of phytohormones from fruit samples followed by high performance liquid chromatography-ultraviolet detection.

Science.gov (United States)

You, Linna; He, Man; Chen, Beibei; Hu, Bin

2017-11-17

In this work, zeolitic imidazolate framework-8 (ZIF-8)/poly (methyl methacrylate-ethyleneglycol dimethacrylate) (MMA-EGDMA) composite monolith was in situ synthesized on stir bar by one-pot polymerization. Compared with the neat monolith, ZIF-8/poly(MMA-EGDMA) composite monolith has larger surface area and pore volume. It also exhibits higher extraction efficiency for target phytohormones than poly(MMA-EGDMA) monolith and commercial polyethylene glycol (PEG) coated stir bar. Based on it, a method of ZIF-8/poly(MMA-EGDMA) monolith coated stir bar sorptive extraction (SBSE)-high performance liquid chromatography-ultraviolet detection (HPLC-UV) was established for the analysis of five phytohormones in apple and pear samples. The developed method exhibited low limits of detection (0.11-0.51μg/L), wide linear range (0.5-500μg/L) and good recoveries (82.7-111%), which demonstrated good application potential of the ZIF-8/monolith coated stir bar in trace analysis of organic compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Women that fight: The female participation in mixed martial arts events

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Lisiane Caroline Rodrigues Hermes

2016-01-01

Full Text Available Sports marketing is in Mixed Martial Arts (MMA a strategic potential, either through the promotion and implementation of events or the interested in sports. Thus, the management of the sports event planning becomes strategic to measure it considers the participation of female athletes in MMA events. This study aims to analyze the participation of females in MMA events, highlighting the perception of the fighters on the current business scenario in this segment. The method is configured as an exploratory and descriptive research with a qualitative approach, where there is information content analysis obtained through an open questionnaire. The results showed that the MMA product planning females is working strategically towards attracting viewers and brand awareness. In addition, further notes to male dominance in this type of sport, emphasizing gender issues related to compensation of the athletes and their occupation. However, it is clear that athletes even challenged by this scenario, remain convinced of their choices by segment.

The Association of Arsenic Exposure and Metabolism With Type 1 and Type 2 Diabetes in Youth: The SEARCH Case-Control Study.

Science.gov (United States)

Grau-Pérez, Maria; Kuo, Chin-Chi; Spratlen, Miranda; Thayer, Kristina A; Mendez, Michelle A; Hamman, Richard F; Dabelea, Dana; Adgate, John L; Knowler, William C; Bell, Ronny A; Miller, Frederick W; Liese, Angela D; Zhang, Chongben; Douillet, Christelle; Drobná, Zuzana; Mayer-Davis, Elizabeth J; Styblo, Miroslav; Navas-Acien, Ana

2017-01-01

Little is known about arsenic and diabetes in youth. We examined the association of arsenic with type 1 and type 2 diabetes in the SEARCH for Diabetes in Youth Case-Control (SEARCH-CC) study. Because one-carbon metabolism can influence arsenic metabolism, we also evaluated the potential interaction of folate and vitamin B12 with arsenic metabolism on the odds of diabetes. Six hundred eighty-eight participants iAs], monomethylated arsenic [MMA], dimethylated arsenic [DMA]), and one-carbon metabolism biomarkers (folate and vitamin B12) were measured in plasma. We used the sum of iAs, MMA, and DMA (∑As) and the individual species as biomarkers of arsenic concentrations and the relative proportions of the species over their sum (iAs%, MMA%, DMA%) as biomarkers of arsenic metabolism. Median ∑As, iAs%, MMA%, and DMA% were 83.1 ng/L, 63.4%, 10.3%, and 25.2%, respectively. ∑As was not associated with either type of diabetes. The fully adjusted odds ratios (95% CI), rescaled to compare a difference in levels corresponding to the interquartile range of iAs%, MMA%, and DMA%, were 0.68 (0.50-0.91), 1.33 (1.02-1.74), and 1.28 (1.01-1.63), respectively, for type 1 diabetes and 0.82 (0.48-1.39), 1.09 (0.65-1.82), and 1.17 (0.77-1.77), respectively, for type 2 diabetes. In interaction analysis, the odds ratio of type 1 diabetes by MMA% was 1.80 (1.25-2.58) and 0.98 (0.70-1.38) for participants with plasma folate levels above and below the median (P for interaction = 0.02), respectively. Low iAs% versus high MMA% and DMA% was associated with a higher odds of type 1 diabetes, with a potential interaction by folate levels. These data support further research on the role of arsenic metabolism in type 1 diabetes, including the interplay with one-carbon metabolism biomarkers. © 2017 by the American Diabetes Association.

The Hanford Site's Gable Mountain structure: A comparison of the recurrence of design earthquakes based on fault slip rates and a probabilistic exposure model

International Nuclear Information System (INIS)

Rohay, A.C.

1991-01-01

Gable Mountain is a segment of the Umtanum Ridge-Gable Mountain structural trend, an east-west trending series of anticlines, one of the major geologic structures on the Hanford Site. A probabilistic seismic exposure model indicates that Gable Mountain and two adjacent segments contribute significantly to the seismic hazard at the Hanford Site. Geologic measurements of the uplift of initially horizontal (11-12 Ma) basalt flows indicate that a broad, continuous, primary anticline grew at an average rate of 0.009-0.011 mm/a, and narrow, segmented, secondary anticlines grew at rates of 0.009 mm/a at Gable Butte and 0.018 mm/a at Gable Mountain. The buried Southeast Anticline appears to have a different geometry, consisting of a single, intermediate-width anticline with an estimated growth rate of 0.007 mm/a. The recurrence rate and maximum magnitude of earthquakes for the fault models were used to estimate the fault slip rate for each of the fault models and to determine the implied structural growth rate of the segments. The current model for Gable Mountain-Gable Butte predicts 0.004 mm/a of vertical uplift due to primary faulting and 0.008 mm/a due to secondary faulting. These rates are roughly half the structurally estimated rates for Gable Mountain, but the model does not account for the smaller secondary fold at Gable Butte. The model predicted an uplift rate for the Southeast Anticline of 0.006 mm/a, caused by the low open-quotes fault capabilityclose quotes weighting rather than a different fault geometry. The effects of previous modifications to the fault models are examined and potential future modifications are suggested. For example, the earthquake recurrence relationship used in the current exposure model has a b-value of 1.15, compared to a previous value of 0.85. This increases the implied deformation rates due to secondary fault models, and therefore supports the use of this regionally determined b-value to this fault/fold system

Associations between Methylated Metabolites of Arsenic and Selenium in Urine of Pregnant Bangladeshi Women and Interactions between the Main Genes Involved.

Science.gov (United States)

Skröder, Helena; Engström, Karin; Kuehnelt, Doris; Kippler, Maria; Francesconi, Kevin; Nermell, Barbro; Tofail, Fahmida; Broberg, Karin; Vahter, Marie

2018-02-01

It has been proposed that interactions between selenium and arsenic in the body may affect their kinetics and toxicity. However, it is unknown how the elements influence each other in humans. We aimed to investigate potential interactions in the methylation of selenium and arsenic. Urinary selenium (U-Se) and arsenic (U-As) were measured using inductively coupled plasma mass spectrometry (ICPMS) in samples collected from pregnant women ( n =226) in rural Bangladesh at gestational weeks (GW) 8, 14, 19, and 30. Urinary concentrations of trimethyl selenonium ion (TMSe) were measured by HPLC-vapor generation-ICPMS, as were inorganic arsenic (iAs), methylarsonic acid (MMA), and dimethylarsinic acid (DMA). Methylation efficiency was assessed based on relative amounts (%) of arsenic and selenium metabolites in urine. Genotyping for the main arsenite and selenium methyltransferases, AS3MT and INMT, was performed using TaqMan probes or Sequenom. Multivariable-adjusted linear regression analyses indicated that %TMSe (at GW8) was positively associated with %MMA (β=1.3, 95% CI: 0.56, 2.0) and U-As, and inversely associated with %DMA and U-Se in producers of TMSe ( INMT rs6970396 AG+AA, n =74), who had a wide range of urinary TMSe (12-42%). Also, %TMSe decreased in parallel to %MMA during pregnancy, especially in the first trimester (-0.58 %TMSe per gestational week). We found a gene-gene interaction for %MMA ( p -interaction=0.076 for haplotype 1). In analysis stratified by INMT genotype, the association between %MMA and both AS3MT haplotypes 1 and 3 was stronger in women with the INMT GG (TMSe nonproducers, 5th-95th percentile: 0.2-2%TMSe) vs. AG+AA genotype. Our findings for Bangladeshi women suggest a positive association between urinary %MMA and %TMSe. Genes involved in the methylation of selenium and arsenic may interact on associations with urinary %MMA. https://doi.org/10.1289/EHP1912.

Iron halide mediated atom transfer radical polymerization of methyl methacrylate with N-Alkyl-2-pyridylmethanimine as the ligand

NARCIS (Netherlands)

Zhang, H.; Schubert, U.S.

2004-01-01

The controlled atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) catalyzed by iron halide/N-(n-hexyl)-2-pyridylmethanimine (NHPMI) is described. The ethyl 2-bromoisobutyrate (EBIB)-initiated ATRP with [MMA]0/[EBIB]0/[iron halide]0/[NHPMI]0 = 150/1/1/2 was better controlled in

The effects of maternal haemoglobin as an indicator of maternal ...

African Journals Online (AJOL)

EB

relationship could exist between MMA of mother-infant pairs and maternal nutritional indicator (haemoglobin). Objectives: This study reviewed the effects of maternal haemoglobin (Hb) on MMA of mother-infant pairs at birth. Methods: One hundred and fifty three mother-infant pairs were enrolled in this study using the ...

Genetic polymorphisms in AS3MT and arsenic metabolism in residents of the Red River Delta, Vietnam

International Nuclear Information System (INIS)

Agusa, Tetsuro; Iwata, Hisato; Fujihara, Junko; Kunito, Takashi; Takeshita, Haruo; Minh, Tu Binh; Trang, Pham Thi Kim; Viet, Pham Hung; Tanabe, Shinsuke

2009-01-01

To elucidate the role of genetic factors in arsenic (As) metabolism, we studied associations of single nucleotide polymorphisms (SNPs) in As (+ 3 oxidation state) methyltransferase (AS3MT) with the As concentrations in hair and urine, and urinary As profile in residents in the Red River Delta, Vietnam. Concentrations of total As in groundwater were 0.7-502 μg/l. Total As levels in groundwater drastically decreased by using sand filter, indicating that the filter could be effective to remove As from raw groundwater. Concentrations of inorganic As (IAs) in urine and total As in hair of males were higher than those of females. A significant positive correlation between monomethylarsonic acid (MMA)/IAs and age in females indicates that older females have higher methylation capacity from IAs to MMA. Body mass index negatively correlated with urinary As concentrations in males. Homozygote for SNPs 4602AA, 35991GG, and 37853GG, which showed strong linkage disequilibrium (LD), had higher percentage (%) of dimethylarsinic acid (DMA) in urine. SNPs 4740 and 12590 had strong LD and associated with urinary %DMA. Although SNPs 6144, 12390, 14215, and 35587 comprised LD cluster, homozygotes in SNPs 12390GG and 35587CC had lower DMA/MMA in urine, suggesting low methylation capacity from MMA to DMA in homo types for these SNPs. SNPs 5913 and 8973 correlated with %MMA and %DMA, respectively. Heterozygote for SNP 14458TC had higher MMA/IAs in urine than TT homozygote, indicating that the heterozygote may have stronger methylation ability of IAs. To our knowledge, this is the first study on the association of genetic factors with As metabolism in Vietnamese.

Síntese e caracterização de copolímeros reticulados à base de estireno, divinilbenzeno e metacrilato de metila com propriedades magnéticas Synthesis and characterization of crosslinked copolymers based on syrene, divinylbenzene and methyl methacrylate with magnetic properties

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Flavio S. Souza

2013-01-01

Full Text Available Neste trabalho, foram sintetizados copolímeros à base de estireno (STY, divinilbenzeno (DVB e metacrilato de metila (MMA com propriedades magnéticas pela técnica de polimerização em suspensão. Os copolímeros foram caracterizados quanto a sua morfologia, ao teor de ferro incorporado, a densidade aparente, a distribuição de tamanho de partículas e as suas propriedades magnéticas. Foi avaliado o efeito da concentração de MMA sobre as características das partículas poliméricas obtidas. Copolímeros que não utilizaram MMA foram, em geral, os que apresentaram maior incorporação de ferro e melhor controle morfológico. Quando a temperatura foi alterada de 80 ºC para 70 ºC e a velocidade de agitação de 480 rpm para 360 rpm, houve aumento no teor de ferro incorporado nas partículas poliméricas.In this work, copolymers based on styrene (STY, divinylbenzene (DVB and methyl methacrylate (MMA with magnetic properties were synthesized using the suspension polymerization technique. The copolymers were characterized according to morphology, iron content incorporated, bulk density, particle size distribution and magnetic properties. The effect of MMA content on the characteristics of polymeric particles was investigated. Generally, copolymers without MMA presented the biggest iron content incorporated and the best morphologic control. When the temperature was decreased from 80 ºC to 70 ºC and the stirring speed was reduced from 480 rpm to 360 rpm the iron content in the polymeric particles increased.

Urinary Arsenic in Human Samples from Areas Characterized by Natural or Anthropogenic Pollution in Italy.

Science.gov (United States)

Minichilli, Fabrizio; Bianchi, Fabrizio; Ronchi, Anna Maria; Gorini, Francesca; Bustaffa, Elisa

2018-02-09

Arsenic is ubiquitous and has a potentially adverse impact on human health. We compared the distribution of concentrations of urinary inorganic arsenic plus methylated forms (uc(iAs+MMA+DMA)) in four Italian areas with other international studies, and we assessed the relationship between uc(iAs+MMA+DMA) and various exposure factors. We conducted a human biomonitoring study on 271 subjects (132 men) aged 20-44, randomly sampled and stratified by area, gender, and age. Data on environmental and occupational exposure and dietary habits were collected through a questionnaire. Arsenic was speciated using chromatographic separation and inductively coupled mass spectrometry. Associations between uc(iAs+MMA+DMA) and exposure factors were evaluated using the geometric mean ratio (GMR) with a 90% confidence interval by stepwise multiple regression analysis. The 95th percentile value of uc(iAs+MMA+DMA) for the whole sample (86.28 µg/L) was higher than other national studies worldwide. A statistical significant correlation was found between uc(iAs+MMA+DMA) and occupational exposure (GMR: 2.68 [1.79-4.00]), GSTT gene (GMR: 0.68 [0.52-0.80]), consumption of tap water (GMR: 1.35 [1.02-1.77]), seafood (GMR: 1.44 [1.11-1.88]), whole milk (GMR: 1.34 [1.04-1.73]), and fruit/vegetables (GMR: 1.37 [1.03-1.82]). This study demonstrated the utility of uc(iAs+MMA+DMA) as a biomarker to assess environmental exposure. In a public health context, this information could be used to support remedial action, to prevent individuals from being further exposed to environmental arsenic sources.

Urinary Arsenic in Human Samples from Areas Characterized by Natural or Anthropogenic Pollution in Italy

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Fabrizio Minichilli

2018-02-01

Full Text Available Arsenic is ubiquitous and has a potentially adverse impact on human health. We compared the distribution of concentrations of urinary inorganic arsenic plus methylated forms (uc(iAs+MMA+DMA in four Italian areas with other international studies, and we assessed the relationship between uc(iAs+MMA+DMA and various exposure factors. We conducted a human biomonitoring study on 271 subjects (132 men aged 20–44, randomly sampled and stratified by area, gender, and age. Data on environmental and occupational exposure and dietary habits were collected through a questionnaire. Arsenic was speciated using chromatographic separation and inductively coupled mass spectrometry. Associations between uc(iAs+MMA+DMA and exposure factors were evaluated using the geometric mean ratio (GMR with a 90% confidence interval by stepwise multiple regression analysis. The 95th percentile value of uc(iAs+MMA+DMA for the whole sample (86.28 µg/L was higher than other national studies worldwide. A statistical significant correlation was found between uc(iAs+MMA+DMA and occupational exposure (GMR: 2.68 [1.79–4.00], GSTT gene (GMR: 0.68 [0.52–0.80], consumption of tap water (GMR: 1.35 [1.02–1.77], seafood (GMR: 1.44 [1.11–1.88], whole milk (GMR: 1.34 [1.04–1.73], and fruit/vegetables (GMR: 1.37 [1.03–1.82]. This study demonstrated the utility of uc(iAs+MMA+DMA as a biomarker to assess environmental exposure. In a public health context, this information could be used to support remedial action, to prevent individuals from being further exposed to environmental arsenic sources.

Local genealogies in a linear mixed model for genome-wide association mapping in complex pedigreed populations.

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Goutam Sahana

Full Text Available INTRODUCTION: The state-of-the-art for dealing with multiple levels of relationship among the samples in genome-wide association studies (GWAS is unified mixed model analysis (MMA. This approach is very flexible, can be applied to both family-based and population-based samples, and can be extended to incorporate other effects in a straightforward and rigorous fashion. Here, we present a complementary approach, called 'GENMIX (genealogy based mixed model' which combines advantages from two powerful GWAS methods: genealogy-based haplotype grouping and MMA. SUBJECTS AND METHODS: We validated GENMIX using genotyping data of Danish Jersey cattle and simulated phenotype and compared to the MMA. We simulated scenarios for three levels of heritability (0.21, 0.34, and 0.64, seven levels of MAF (0.05, 0.10, 0.15, 0.20, 0.25, 0.35, and 0.45 and five levels of QTL effect (0.1, 0.2, 0.5, 0.7 and 1.0 in phenotypic standard deviation unit. Each of these 105 possible combinations (3 h(2 x 7 MAF x 5 effects of scenarios was replicated 25 times. RESULTS: GENMIX provides a better ranking of markers close to the causative locus' location. GENMIX outperformed MMA when the QTL effect was small and the MAF at the QTL was low. In scenarios where MAF was high or the QTL affecting the trait had a large effect both GENMIX and MMA performed similarly. CONCLUSION: In discovery studies, where high-ranking markers are identified and later examined in validation studies, we therefore expect GENMIX to enrich candidates brought to follow-up studies with true positives over false positives more than the MMA would.

Use of Combined Observational- and Model-Derived Photochemical Indicators to Assess the O3-NOx-VOC System Sensitivity in Urban Areas

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Edson R. Carrillo-Torres

2017-01-01

Full Text Available Tropospheric levels of O3 have historically exceeded the official annual Mexican standards within the Monterrey Metropolitan Area (MMA in NE Mexico. High-frequency and high-precision measurements of tropospheric O3, NOy, NO2, NO, CO, SO2, PM10 and PM2.5 were made at the Obispado monitoring site near the downtown MMA from September 2012 to August 2013. The seasonal cycles of O3 and NOy are driven by changes in meteorology and to a lesser extent by variations in primary emissions. The NOy levels were positively correlated with O3 precursors and inversely correlated with O3 and wind speed. Recorded data were used to assess the O3-Volatile Organic Compounds (VOC-NOx system’s sensitivity through an observational-based approach. The photochemical indicator O3/NOy was derived from measured data during the enhanced O3 production period (12:00–18:00 Central Daylight Time (CDT, GMT-0500. The O3/NOy ratios calculated for this time period showed that the O3 production within the MMA is VOC sensitive. A box model simulation of production rates of HNO3 (PHNO3 and total peroxides (Pperox carried out for O3 episodes in fall and spring confirmed the VOC sensitivity within the MMA environment. No significant differences were observed in O3/NOy from weekdays to weekends or for PHNO3/Pperox ratios, confirming the limiting role of VOCs in O3 production within the MMA. The ratified photochemical regime observed may allow the environmental authorities to revise and verify the current policies for air quality control within the MMA.

Urinary Arsenic in Human Samples from Areas Characterized by Natural or Anthropogenic Pollution in Italy

Science.gov (United States)

Minichilli, Fabrizio; Bianchi, Fabrizio; Ronchi, Anna Maria; Gorini, Francesca; Bustaffa, Elisa

2018-01-01

Arsenic is ubiquitous and has a potentially adverse impact on human health. We compared the distribution of concentrations of urinary inorganic arsenic plus methylated forms (uc(iAs+MMA+DMA)) in four Italian areas with other international studies, and we assessed the relationship between uc(iAs+MMA+DMA) and various exposure factors. We conducted a human biomonitoring study on 271 subjects (132 men) aged 20–44, randomly sampled and stratified by area, gender, and age. Data on environmental and occupational exposure and dietary habits were collected through a questionnaire. Arsenic was speciated using chromatographic separation and inductively coupled mass spectrometry. Associations between uc(iAs+MMA+DMA) and exposure factors were evaluated using the geometric mean ratio (GMR) with a 90% confidence interval by stepwise multiple regression analysis. The 95th percentile value of uc(iAs+MMA+DMA) for the whole sample (86.28 µg/L) was higher than other national studies worldwide. A statistical significant correlation was found between uc(iAs+MMA+DMA) and occupational exposure (GMR: 2.68 [1.79–4.00]), GSTT gene (GMR: 0.68 [0.52–0.80]), consumption of tap water (GMR: 1.35 [1.02–1.77]), seafood (GMR: 1.44 [1.11–1.88]), whole milk (GMR: 1.34 [1.04–1.73]), and fruit/vegetables (GMR: 1.37 [1.03–1.82]). This study demonstrated the utility of uc(iAs+MMA+DMA) as a biomarker to assess environmental exposure. In a public health context, this information could be used to support remedial action, to prevent individuals from being further exposed to environmental arsenic sources. PMID:29425136

Photolysis of hexaarylbiimidazole sensitized by dyes and application in photopolymerization

Institute of Scientific and Technical Information of China (English)

GAO, Fang(高放); XU, Jin- Qi(徐锦棋); SONG, Xiao-You(宋晓友); LI, Li-Dong(李立东); YANG, Yong-Yuan(杨永源); FENG, Shu-Jing(冯树京)

2000-01-01

Kinetic studies on the near-UV photo-initiating polymerization of methylmethacrylate (MMA) sensitized by dye/hexaarylbiimidazole systems were carried out. When exposed to highpressure mercury lamp (filtered by Pyrex glass), dye/hexaarylbiimidazole system undergoes quick electron transfer and free radicals are produced. RSH, as hydrogen donor, can improve the polymerization efficiency of MMA. Comparisons of influence of different dyes and different RSH on the conversion of MMA photopolymerization were carried out. Excellent results have been obtained in photoimaging studies, e.g. a minimum exposure energy of the photosensitive systems of 8 mJ/cm2 can be reached and the resolution of presensitized printing plate was ca. 10μm.

DYE-SENSITIZED PHOTOPOLYMERIZATION OF METHYL METHACRYLATE INITIATED BY COUMARIN DYE/IODONIUM SALT SYSTEM

Institute of Scientific and Technical Information of China (English)

Fang Gao; Yong-yuan Yang

1999-01-01

The photosensitive initiating system composed of 7-diethylamino-3-(2'-benzimidazolyl)coumarin dye (DEDC) and diphenyliodonium hexafluorophosphate (DIHP) which act as the sensitizer and the initiator respectively, can be used to initiate the polymerization of methyl methacrylate (MMA). The results showed that when exposed to visible light, coumarin dye/iodonium salt undergoes quick electron transfer from DEDC to DIHP and free radicals are produced. The visible light photoinduced reaction between DEDC and DIHP is mainly through the excited singlet state of DEDC and thus it is a little sensitive to O2. The influence of concentration of DEDC, DIHP and MMA on the rate of photopolymerization of MMA was also investigated.

Artes marciais mistas: luta por afirmação e mercado da luta

OpenAIRE

Millen Neto, Alvaro Rego; Garcia, Roberto Alves; Votre, Sebastião Josué

2016-01-01

Resumo O artigo analisa o processo de construção das artes marciais mistas (MMA), descreve parte da história do valetudo no Brasil, de sua internacionalização, e identifica as marcas de ruptura entre o valetudo e o MMA. Foram consideradas como características próprias da transição do valetudo para o MMA: a profissionalização da categoria; a aceitação pelos veículos de comunicação; o acirramento do controle do corpo e dos códigos de moralidade no ethos dos lutadores; a criação de um novo produ...

Prenatal identification of a novel mutation causing methylmalonic ...

Indian Academy of Sciences (India)

2015-06-08

Jun 8, 2015 ... respiratory distress, intellectual disability etc. The nonspe- cific nature of these ... disease can vary from being benign to fatal (Matsui et al. 1983; Ledley et al. ... soon after the infant was introduced to solid food. The con-.

Identification of the Mycobacterium marinum Apa antigen O-mannosylation sites reveals important glycosylation variability with the M. tuberculosis Apa homologue.

Science.gov (United States)

Coddeville, Bernadette; Wu, Sz-Wei; Fabre, Emeline; Brassart, Colette; Rombouts, Yoann; Burguière, Adeline; Kremer, Laurent; Khoo, Kay-Hooi; Elass-Rochard, Elisabeth; Guérardel, Yann

2012-10-22

The 45/47 kDa Apa, an immuno-dominant antigen secreted by Mycobacterium tuberculosis is O-mannosylated at multiple sites. Glycosylation of Apa plays a key role in colonization and invasion of the host cells by M. tuberculosis through interactions of Apa with the host immune system C-type lectins. Mycobacterium marinum (M.ma) a fish pathogen, phylogenetically close to M. tuberculosis, induces a granulomatous response with features similar to those described for M. tuberculosis in human. Although M.ma possesses an Apa homologue, its glycosylation status is unknown, and whether this represents a crucial element in the pathophysiology induced by M.ma remains to be addressed. To this aim, we have identified two concanavalin A-reactive 45/47 kDa proteins from M.ma, which have been further purified by a two-step anion exchange chromatography process. Advanced liquid chromatography-nanoESI mass spectrometry-based proteomic analyses of peptides, derived from either tryptic digestion alone or in combination with the Asp-N endoproteinase, established that M.ma Apa possesses up to seven distinct O-mannosylated sites with mainly single mannose substitutions, which can be further extended at the Ser/Thr/Pro rich region near the N-terminus. This opens the way to further studies focussing on the involvement and biological functions of Apa O-mannosylation using the M.ma/zebrafish model. Copyright © 2012 Elsevier B.V. All rights reserved.

Creatinine, diet, micronutrients, and arsenic methylation in West Bengal, India.

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Basu, Arin; Mitra, Soma; Chung, Joyce; Guha Mazumder, D N; Ghosh, Nilima; Kalman, David; von Ehrenstein, Ondine S; Steinmaus, Craig; Liaw, Jane; Smith, Allan H

2011-09-01

Ingested inorganic arsenic (InAs) is methylated to monomethylated (MMA) and dimethylated metabolites (DMA). Methylation may have an important role in arsenic toxicity, because the monomethylated trivalent metabolite [MMA(III)] is highly toxic. We assessed the relationship of creatinine and nutrition--using dietary intake and blood concentrations of micronutrients--with arsenic metabolism, as reflected in the proportions of InAS, MMA, and DMA in urine, in the first study that incorporated both dietary and micronutrient data. We studied methylation patterns and nutritional factors in 405 persons who were selected from a cross-sectional survey of 7,638 people in an arsenic-exposed population in West Bengal, India. We assessed associations of urine creatinine and nutritional factors (19 dietary intake variables and 16 blood micronutrients) with arsenic metabolites in urine. Urinary creatinine had the strongest relationship with overall arsenic methylation to DMA. Those with the highest urinary creatinine concentrations had 7.2% more arsenic as DMA compared with those with low creatinine (p creatinine concentration was the strongest biological marker of arsenic methylation efficiency, and therefore should not be used to adjust for urine concentration in arsenic studies. The new finding that animal fat intake has a positive relationship with MMA% warrants further assessment in other studies. Increased MMA% was also associated, to a lesser extent, with low serum selenium and folate.

Fatores de risco maternos associados à acidose fetal Maternal risk factors associated with fetal acidosis

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José Mauro Madi

2010-09-01

Full Text Available OBJETIVOS: avaliar os fatores de risco maternos associados à acidose fetal. MÉTODOS: estudo tipo caso-controle composto por 188 recém-nascidos, sendo que 47 compuseram o grupo casos (pH de artéria umbilical OBJECTIVES: to assess maternal risk factors associated with fetal acidosis. METHODS: a case-control type study was conducted of 188 neonates, of whom 47 comprised the case group (umbilical arterial pH <7.0 and 141 the control (umbilical arterial pH E7.1 <7.3. The study included only single-gestation neonates without congenital malformations. Both maternal and fetal variables were taken into consideration. Statistical analysis involved the calculation of the raw and adjusted Odds Ratio, Student's t-test, the chi-squared test and multivariate analysis using Enter-method non-conditional logistic regression. The level of statistical significance was set at p<0.05. RESULTS: in the case group higher percentages of caesarian sections and pre-term births were observed, involving almost five times as much intensive care and twenty-five times more likelihood of Apgar in the 5th minute <7. No association was observed between the groups and fetal presentation, mother's age, history of miscarriage, years of schooling of mother or attendance at prenatal sessions. After multivariate analysis, the only risk factors that remained significant were complications relating to the placenta or the umbilical cord. Deliveries involving complications relating to the placenta or the umbilical cord were three times more likely to involve fetal acidemia. CONCLUSIONS: acidemia among neonates was associated with a higher percentage of caesarians, premature births, a need for intensive care and treatment and an Apgar index of <7 in the 5th minute. After multivariate analysis, complications relating to premature displacement of the placenta and the umbilical cord were the only remaining risk factors associated with fetal acidemia.

Infusion of sodium bicarbonate in experimentally induced metabolic acidosis does not provoke cerebrospinal fluid (CSF) acidosis in calves.

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Abeysekara, Saman; Zello, Gordon A; Lohmann, Katharina L; Alcorn, Jane; Hamilton, Don L; Naylor, Jonathan M

2012-01-01

In a crossover study, 5 calves were made acidotic by intermittent intravenous infusion of isotonic hydrochloric acid (HCl) over approximately 24 h. This was followed by rapid (4 h) or slow (24 h) correction of blood pH with isotonic sodium bicarbonate (NaHCO(3)) to determine if rapid correction of acidemia produced paradoxical cerebrospinal fluid (CSF) acidosis. Infusion of HCl produced a marked metabolic acidosis with respiratory compensation. Venous blood pH (mean ± S(x)) was 7.362 ± 0.021 and 7.116 ± 0.032, partial pressure of carbon dioxide (Pco(2), torr) 48.8 ± 1.3 and 34.8 ± 1.4, and bicarbonate (mmol/L), 27.2 ± 1.27 and 11 ± 0.96; CSF pH was 7.344 ± 0.031 and 7.240 ± 0.039, Pco(2) 42.8 ± 2.9 and 34.5 ± 1.4, and bicarbonate 23.5 ± 0.91 and 14.2 ± 1.09 for the period before the infusion of hydrochloric acid and immediately before the start of sodium bicarbonate correction, respectively. In calves treated with rapid infusion of sodium bicarbonate, correction of venous acidemia was significantly more rapid and increases in Pco(2) and bicarbonate in CSF were also more rapid. However, there was no significant difference in CSF pH. After 4 h of correction, CSF pH was 7.238 ± 0.040 and 7.256 ± 0.050, Pco(2) 44.4 ± 2.2 and 34.2 ± 2.1, and bicarbonate 17.8 ± 1.02 and 14.6 ± 1.4 for rapid and slow correction, respectively. Under the conditions of this experiment, rapid correction of acidemia did not provoke paradoxical CSF acidosis.

Using the pulse electron beam for air purification from methylmethacrylate vapors

International Nuclear Information System (INIS)

Drachev, A.N.; Novoselov, Yu.N.; Filatov, I.E.

2003-01-01

The results of studying the methylmethacrylate (MMA) vapors destruction in the mixture of nitrogen with oxygen under the pulse electron beam effect are presented. The competing mechanisms for the MMA removal are identified: the first one proceeds without the oxygen participation and the second one with the oxygen active forms participation [ru

Research of Polylactic Acid Modiifed by Polymethyl Acrylate-Methyl Methacrylate Copolymer%聚丙烯酸甲酯-甲基丙烯酸甲酯共聚物改性聚乳酸的研究

Institute of Scientific and Technical Information of China (English)

苏桂仙; 李光辉; 和芹; 李德玲

2015-01-01

为了提高聚乳酸(PLA)的韧性，采用聚丙烯酸甲酯-甲基丙烯酸甲酯(PMA-MMA)对PLA进行共混改性。采用悬浮聚合法，以丙烯酸甲酯(MA)、甲基丙烯酸甲酯(MMA)为共聚单体，制备珠粒状的PMA-MMA共聚物。通过熔融共混法，分别以PMA-MMA共聚物为增韧剂，聚乙二醇为增塑剂，聚乙烯蜡为润滑剂，对PLA进行改性，对改性后的PLA复合材料的热性能和力学性能进行研究。结果表明，随着PMA-MMA共聚物用量的增加，PLA复合材料的拉伸强度呈先增大后减小的趋势，而断裂伸长率和冲击强度不断增大。当PMA-MMA共聚物用量为15份时， PLA复合材料的拉伸强度达到最大值，为52.2 MPa；当PMA-MMA共聚物用量为25份时，PLA复合材料冲击强度为53.26 kJ／m2，是纯PLA的4.4倍，断裂伸长率为54.9%。PMA-MMA共聚物与PLA的相容性好，有明显的增韧作用。PMA-MMA共聚物的加入并未降低PLA复合材料的热性能。%In order to improve the toughness of poly(lactic acid)(PLA),polymethyl acrylate-methyl methacrylate(PMA-MMA) copolymer was used to mix with PLA. Methyl acrylate (MA) and methyl methacrylate(MMA) were used as the monomers for the preparation of PMA-MMA copolymer by means of suspention polymerization. PLA and PMA-MMA copolymer were melt-blended with polyethylene glycol(PEG) as a plasticizer and polyethylene as a lubricant. The modified PLA composites were studied by means of heat resistance and mechanical properties. The results show that with the increase of PMA-MMA copolymer content, the elongation at break and impact strength of the composites are improved,and its tensile strength increases first and then decreases. While the content of PMA-MMA copolymer is 15 phr,the tensile strength of the composite has the best tensile strength of 52.2 MPa. While the content of PMA-MMA copolymer is 25 phr,the impact strength of the composite is 53.26 kJ/m2,which is the 4.4 times of the pure PLA

Attacking the Body in Mixed Martial Arts: Perspectives, Opinions and Perceptions of the Full Contact Combat Sport of Ultimate Fighting

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Magnus Tobias Stenius

2015-02-01

Full Text Available This article explores the sensuous experience of full contact fighting through ethnographic research in mixed martial arts clubs. Presenting its first card in 1993 in Denver, Colorado, the Ultimate Fighting Championship (UFC stunned martial artists while thrilling and frightening spectators. Mixed martial arts (MMA is an evolving combat sport pitting elite athletes trained in a variety of combat arts against each other in the “Octagon”. Contestants are permitted to kick, punch, elbow and knee as well as use grappling submission techniques to defeat opponents. Despite criticism, supporters claim that the efficiency of non-violent grappling techniques has made MMA much safer than boxing, where fighters absorb repeated blows to the head. As the sport developed, fighters adjusted their bodies in order to better utilize the positional, tactical techniques that proved more successful than brute force. The mediated representation of fighting revealed that despite of being in a state of rage, MMA was a technically challenging sport based on the sublime performance of participant’s bodies. However, MMA remains the subject of debate in popular culture and the media, and medical expertise argues that the sport is dangerous and puts participants in harm´s way. On the other hand, proponents of the sport argue that health risks are overstated and that other, far less safe sports exist. The aim of this article is to scrutinize fighters as well as the opinions of media and the medical humanities in order to achieve an overview of the image of this combat sport. Convinced that the debate needs to be more nuanced, this paper examines how MMA encounters and mitigates scientific discourse and attitudes. The results also show that MMA is an ambiguous sport, taking responsibility for the well being of its fighters while encouraging spectacle in the arena.

Differences of Urinary Arsenic Metabolites and Methylation Capacity between Individuals with and without Skin Lesions in Inner Mongolia, Northern China

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Qiang Zhang

2014-07-01

Full Text Available Incomplete arsenic (As methylation has been considered a risk factor of As-related diseases. This study aimed to examine the difference of urinary As metabolites and the methylation capacity between subjects with and without skin lesions. Urinary inorganic arsenic (iAs, monomethylarsonic acid (MMA, and dimethylarsinic acid (DMA were analyzed. The percentage of each As species (iAs%, MMA%, and DMA%, the primary methylation index (PMI and secondary methylation index (SMI were calculated. The results showed that subjects with skin lesions have higher levels of urinary iAs (99.08 vs. 70.63 μg/g Cr, p = 0.006 and MMA (69.34 vs. 42.85 μg/g Cr, p = 0.016 than subjects without skin lesions after adjustment for several confounders. Significant differences of urianry MMA% (15.49 vs. 12.11, p = 0.036 and SMI (0.74 vs. 0.81, p = 0.025 were found between the two groups. The findings of the present study suggest that subjects with skin lesions may have a lower As methylation capacity than subjects without skin lesions.

Evaluation of Muscle Damage Marker after Mixed Martial Arts Matches.

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Wiechmann, Gerald Julius; Saygili, Erol; Zilkens, Christoph; Krauspe, Rüdiger; Behringer, Michael

2016-03-21

The aim of this paper is to identify predictors of serum muscle damage marker (MDM) response following mixed martial arts (MMA) matches. Creatine kinase activity (CK) and myoglobin concentration (Mb) were measured in ten male elite MMA fighters (aged 28±5.7 years) prior to, 2 h, 24 h, and 96 h following 9 different MMA matches. The number of performed upright punches and kicks (UKF) that failed the opponent, the number of obtained hits to the upper and lower body (LBH), as well as the total fight duration (TFD) were evaluated as potential predictors from video recordings. CK peaked 24 h (829±753 U/L(-1)) and Mb peaked 2 h (210±122 µg/L(-1)) post matches. Almost 80% of the peak CK variance could be explained by LBH and UKF, whereas 87% of the Mb variation was explained by TFD and LBH. MMA result in a significant skeletal muscle damage, which largely depends on LBH. Furthermore, eccentric contractions to decelerate kicks that missed the opponent and the TFD seem to contribute to the MDM response.

Surface Modification of Sodium Montmorillonite Nanoclay by Plasma Polymerization and Its Effect on the Properties of Polystyrene Nanocomposites

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Rosa Idalia Narro-Céspedes

2018-01-01

Full Text Available Sodium montmorillonite nanoclay (Na+-MMT was modified by plasma polymerization with methyl methacrylate (MMA and styrene (St as monomers and was denominated as Na+-MMT/MMA and Na+-MMT/St, respectively. This plasma modified nanoclay was used as reinforcement for polystyrene (PS nanocomposites that were prepared by melt mixing. Pristine and modified Na+-MMT nanoclay were analyzed by the dispersion in various solvents, Fourier transform infrared spectroscopy (FTIR, thermogravimetric analysis (TGA, and scanning electron microscopy (SEM. The results confirmed a change in hydrophilicity of the modified Na+-MMT, as well as the presence of a polymeric material over its surface. The pristine PS/Na+-MMT and modified PS/Na+-MMT/MMA and PS/Na+-MMT/St nanocomposites were studied with X-ray diffraction (XRD, differential scanning calorimetry (DSC, and TGA, as well as mechanical properties. It was found that the PS/Na+-MMT/St nanocomposites presented better thermal properties and an improvement in Young’s modulus (YM in compared to PS/Na+-MMT/MMA nanocomposites.

Differences of urinary arsenic metabolites and methylation capacity between individuals with and without skin lesions in Inner Mongolia, Northern China.

Science.gov (United States)

Zhang, Qiang; Li, Yongfang; Liu, Juan; Wang, Da; Zheng, Quanmei; Sun, Guifan

2014-07-18

Incomplete arsenic (As) methylation has been considered a risk factor of As-related diseases. This study aimed to examine the difference of urinary As metabolites and the methylation capacity between subjects with and without skin lesions. Urinary inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were analyzed. The percentage of each As species (iAs%, MMA%, and DMA%), the primary methylation index (PMI) and secondary methylation index (SMI) were calculated. The results showed that subjects with skin lesions have higher levels of urinary iAs (99.08 vs. 70.63 μg/g Cr, p = 0.006) and MMA (69.34 vs. 42.85 μg/g Cr, p = 0.016) than subjects without skin lesions after adjustment for several confounders. Significant differences of urianry MMA% (15.49 vs. 12.11, p = 0.036) and SMI (0.74 vs. 0.81, p = 0.025) were found between the two groups. The findings of the present study suggest that subjects with skin lesions may have a lower As methylation capacity than subjects without skin lesions.

Assignment of electron transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO) to human chromosome 4q33 by fluorescence in situ hybridization and somatic cell hybridization.

Science.gov (United States)

Spector, E B; Seltzer, W K; Goodman, S I

1999-08-01

Electron transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO) is a nuclear-encoded protein located in the inner mitochondrial membrane. Inherited defects of ETF-QO cause glutaric acidemia type II. We here describe the localization of the ETF-QO gene to human chromosome 4q33 by somatic cell hybridization and fluorescence in situ hybridization. Copyright 1999 Academic Press.

Maintaining physical exercise as a matter of synchronising practices: Experiences and observations from training in Mixed Martial Arts.

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Blue, Stanley

2017-07-01

This paper is concerned with the establishment, maintenance, and decline of physical exercise practices. Drawing on experiences and observations taken from a carnal ethnography and rhythmanalysis of the practices involved in training in Mixed Martial Arts (MMA), I argue that maintaining this physical exercise practice is not straightforwardly an outcome of individual commitment, access to facilities, or the availability of free time. It rather depends on the synchronisation of practices: those of MMA, those that support MMA, and those that more broadly make up everyday life. This research suggests that increasing rates of physical activity might be better fostered through facilitating the integration of combinations of healthy activities into everyday life. Copyright © 2016 Elsevier Ltd. All rights reserved.

Surface-Initiated Graft Atom Transfer Radical Polymerization of Methyl Methacrylate from Chitin Nanofiber Macroinitiator under Dispersion Conditions

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Ryo Endo

2015-08-01

Full Text Available Surface-initiated graft atom transfer radical polymerization (ATRP of methyl methacrylate (MMA from self-assembled chitin nanofibers (CNFs was performed under dispersion conditions. Self-assembled CNFs were initially prepared by regeneration from a chitin ion gel with 1-allyl-3-methylimidazolium bromide using methanol; the product was then converted into the chitin nanofiber macroinitiator by reaction with α-bromoisobutyryl bromide in a dispersion containing N,N-dimethylformamide. Surface-initiated graft ATRP of MMA from the initiating sites on the CNFs was subsequently carried out under dispersion conditions, followed by filtration to obtain the CNF-graft-polyMMA film. Analysis of the product confirmed the occurrence of the graft ATRP on the surface of the CNFs.

K-ATP channel expression and pharmacological in vivo and in vitro studies of the K-ATP channel blocker PNU-37883A in rat middle meningeal arteries

DEFF Research Database (Denmark)

Ploug, K.B.; Boni, L.J.; Baun, M.

2008-01-01

closed cranial window model and in myograph baths, respectively. Key results: Expression studies indicate that inwardly rectifying K+ (Kir)6.1/sulphonylurea receptor (SUR) 2B is the major K-ATP channel complex in rat MMA. PNU-37883A (0.5 mg kg(-1)) significantly inhibited the in vivo dilatory effect...... of levcromakalim (0.025 mg kg(-1)), pinacidil (0.38 mg kg(-1)) and P-1075 (0.016 mg kg(-1)) in rat MMA. In vitro PNU-37883A significantly inhibited the dilatory responses of the three K-ATP channel openers in rat MMA at 10(-7) and 3 x 10(-7) M. Conclusions and implications: We suggest that Kir6.1/SUR2B...

Controlled/living photopolymerization of methyl methacrylate in miniemulsion mediated by HTEMPO

Institute of Scientific and Technical Information of China (English)

Xiaoxuan LIU; Yanni JING; Yingkun BAI

2008-01-01

Controlled/living photopolymerization of methyl methacrylate (MMA) in miniemulsion mediated by 4-hydroxy-2,2,6,6-tetramethyl-piperidinyloxy (HTEMPO) was carried out at ambient temperatures. MMA miniemulsion was prepared by using an anionic surfactant with cetylalcohol as a co-stabilizer. The photopolymerization led to stable lattices and they were obtained with no coagulation during synthesis and no destabilization over time. It was found that the obtained MMA homopolymers exhibited relatively narrow mole-cular weight distribution (PDI = 1.27- 1.36) which was characterized by GPC. The plots of number-average molecular weight in (Mn) vs. Conversion and ln([MO]/[M]) vs. Time both were linear indicating that the reaction was a controlled/living free radical polymerization.

Polymerization of methyl methacrylate by diphenylamido bis (methylcyclopentadienyl) ytterbium complex

Institute of Scientific and Technical Information of China (English)

WANG, Yao-Rong(王耀荣); SHEN, Qi(沈琪); MA, Jia-Le(马家乐); ZHAO, Qun(赵群)

2000-01-01

Methyl methacrylate (MMA) was effectively polymerized by diphenylamido bis(methyicyclopentadienyl) ytterbium complex (MeCp)2YbNPh2(THF). Tne reaction can be carried out over a range of polymerization temperature from - 40℃ to 40℃ and gives the polyMMA with high molecular weights.The initiation mechanism was demonstrated by diphenylamidoterminated methyl methacrylate oligomer.

The Epidemiology of Injuries in Mixed Martial Arts: A Systematic Review and Meta-analysis.

Science.gov (United States)

Lystad, Reidar P; Gregory, Kobi; Wilson, Juno

2014-01-01

Mixed martial arts (MMA) has experienced a surge in popularity since emerging in the 1990s, but the sport has also faced concomitant criticism from public, political, and medical holds. Notwithstanding the polarized discourse concerning the sport, no systematic review of the injury problems in MMA has been published to date. To systematically review the epidemiologic data on injuries in MMA and to quantitatively estimate injury incidence and risk factor effect sizes. Systematic review and meta-analysis; Level of evidence, 4. Electronic searching of PubMed, Scopus, CINAHL, EMBASE, AMED, and SPORTDiscus databases to identify studies reporting on the epidemiology of injuries in MMA. Random-effects models were used to obtain pooled summary estimates of the injury incidence rate per 1000 athlete-exposures (IIRAE) and rate ratios with 95% confidence intervals (CIs). Heterogeneity was evaluated with the I (2) statistic. A total of 6 studies were eligible for inclusion in this review. The IIRAE summary estimate was found to be 228.7 (95% CI, 110.4-473.5). No studies reported injury severity. The most commonly injured anatomic region was the head (range, 66.8%-78.0%) followed by the wrist/hand (range, 6.0%-12.0%), while the most frequent injury types were laceration (range, 36.7%-59.4%), fracture (range, 7.4%-43.3%), and concussion (range, 3.8%-20.4%). The most notable risk factors pertained to the outcome of bouts. Losers incurred 3 times as many injuries as winners, and fighters in bouts ending with knockout or technical knockout incurred more than 2 times as many injuries as fighters in bouts ending with submission. Notwithstanding the paucity of data, the injury incidence in MMA appears to be greater than in most, if not all, other popular and commonly practiced combat sports. In general, the injury pattern in MMA is very similar to that in professional boxing but unlike that found in other combat sports such as judo and taekwondo. More epidemiologic research is

The Epidemiology of Injuries in Mixed Martial Arts

Science.gov (United States)

Lystad, Reidar P.; Gregory, Kobi; Wilson, Juno

2014-01-01

Background: Mixed martial arts (MMA) has experienced a surge in popularity since emerging in the 1990s, but the sport has also faced concomitant criticism from public, political, and medical holds. Notwithstanding the polarized discourse concerning the sport, no systematic review of the injury problems in MMA has been published to date. Purpose: To systematically review the epidemiologic data on injuries in MMA and to quantitatively estimate injury incidence and risk factor effect sizes. Study Design: Systematic review and meta-analysis; Level of evidence, 4. Methods: Electronic searching of PubMed, Scopus, CINAHL, EMBASE, AMED, and SPORTDiscus databases to identify studies reporting on the epidemiology of injuries in MMA. Random-effects models were used to obtain pooled summary estimates of the injury incidence rate per 1000 athlete-exposures (IIRAE) and rate ratios with 95% confidence intervals (CIs). Heterogeneity was evaluated with the I 2 statistic. Results: A total of 6 studies were eligible for inclusion in this review. The IIRAE summary estimate was found to be 228.7 (95% CI, 110.4-473.5). No studies reported injury severity. The most commonly injured anatomic region was the head (range, 66.8%-78.0%) followed by the wrist/hand (range, 6.0%-12.0%), while the most frequent injury types were laceration (range, 36.7%-59.4%), fracture (range, 7.4%-43.3%), and concussion (range, 3.8%-20.4%). The most notable risk factors pertained to the outcome of bouts. Losers incurred 3 times as many injuries as winners, and fighters in bouts ending with knockout or technical knockout incurred more than 2 times as many injuries as fighters in bouts ending with submission. Conclusion: Notwithstanding the paucity of data, the injury incidence in MMA appears to be greater than in most, if not all, other popular and commonly practiced combat sports. In general, the injury pattern in MMA is very similar to that in professional boxing but unlike that found in other combat sports

Assessment of biological chromium among stainless steel and mild steel welders in relation to welding processes.

Science.gov (United States)

Edmé, J L; Shirali, P; Mereau, M; Sobaszek, A; Boulenguez, C; Diebold, F; Haguenoer, J M

1997-01-01

Air and biological monitoring were used for assessing external and internal chromium exposure among 116 stainless steel welders (SS welders) using manual metal arc (MMA), metal inert gas (MIG) and tungsten inert gas (TIG) welding processes (MMA: n = 57; MIG: n = 37; TIG: n = 22) and 30 mild steel welders (MS welders) using MMA and MIG welding processes (MMA: n = 14; MIG: n = 16). The levels of atmospheric total chromium were evaluated after personal air monitoring. The mean values for the different groups of SS welders were 201 micrograms/m3 (MMA) and 185 micrograms/m3 (MIG), 52 micrograms/m3 (TIG) and for MS welders 8.1 micrograms/m3 (MMA) and 7.3 micrograms/m3 (MIG). The curve of cumulative frequency distribution from biological monitoring among SS welders showed chromium geometric mean concentrations in whole blood of 3.6 micrograms/l (95th percentile = 19.9), in plasma of 3.3 micrograms/l (95th percentile = 21.0) and in urine samples of 6.2 micrograms/l (95th percentile = 58.0). Among MS welders, mean values in whole blood and plasma were rather more scattered (1.8 micrograms/l, 95th percentile = 9.3 and 1.3 micrograms/l, 95th percentile = 8.4, respectively) and in urine the value was 2.4 micrograms/l (95th percentile = 13.3). The analysis of variance of chromium concentrations in plasma previously showed a metal effect (F = 29.7, P process effect (F = 22.2, P process interaction (F = 1.3, P = 0.25). Concerning urinary chromium concentration, the analysis of variance also showed a metal effect (F = 30, P process effect (F = 72, P process interaction (F = 13.2, P = 0.0004). Throughout the study we noted any significant differences between smokers and non-smokers among welders. Taking in account the relationships between chromium concentrations in whole, plasma or urine and the different welding process. MMA-SS is definitely different from other processes because the biological values are clearly higher. These higher levels are due to the very significant

Radiation synthesis and characterization of zinc phthalocyanine composite based on 2-hydroxyethyl methacrylate/methyl methacrylate copolymer

International Nuclear Information System (INIS)

Abdel Ghaffar, A.M.; Youssef, Tamer E.; Mohamed, Hanan H.

2016-01-01

The synthesis and characterization of new 2-hydroxyethyl methacrylate-co-methyl methacrylate/zinc phthalocyanine composite Poly(HEMA/MMA/ZnPc) is described for the first time in this study. The aim of this research is to present possibility of radiation synthesis of the newly zinc phthalocyanine composites as potential candidates for wide range of applications. Gel (%) and swelling for Poly(hydroxyethyl methacrylate) Poly(HEMA) and the based Poly(hydroxyethyl methacrylate/methyl methacrylate) copolymer Poly(HEMA/MMA) with different composition 100/0, 95/5, 90/10 and 80/20 wt % were evaluated. It was found that Poly(HEMA/MMA) copolymer with composition 95/5 wt % characterized by its high swelling property at pH 7.4. The prepared composites I and II Poly(HEMA/MMA/ZnPc) with composition (95/5/1 wt%) and (95/5/1.5 wt%) respectively have been characterized by FTIR and TGA. The effect of gamma irradiation on the chemical properties of composite I was described. It is observed that the Zinc phthalocyanine with low concentration 1 wt % enhance chemical, thermal properties and stabilization against gamma radiation of the prepared composite I. - Highlights: • The preparation of Poly(HEMA/MMA/ZnPc) by radiation forming modified composites. • The low concentration of ZcPc (1 or 1.5 wt %) lead to form outstanding properties. • These composites are a potential candidate for wide range of applications.

Radiation synthesis and characterization of zinc phthalocyanine composite based on 2-hydroxyethyl methacrylate/methyl methacrylate copolymer

Energy Technology Data Exchange (ETDEWEB)

Abdel Ghaffar, A.M., E-mail: am_abdelghaffar@yahoo.com [Radiation Research of Polymer Chemistry Department, Industrial Irradiation Division, National Center for Radiation Research and Technology, Atomic Energy Authority P.O. Box 29, Nasr City, Cairo (Egypt); Youssef, Tamer E. [Applied Organic Chemistry Department, Chemical Industries Research Division, National Research Center, Dokki, Cairo, 12622 (Egypt); Chemical and Materials Engineering Department, Faculty of Engineering, King Abdulaziz University, P.O. Box 80204, Jeddah, 21589 (Saudi Arabia); Mohamed, Hanan H. [Chemistry Department, Faculty of Science, Helwan University, Ain Helwan, Cairo (Egypt)

2016-08-01

The synthesis and characterization of new 2-hydroxyethyl methacrylate-co-methyl methacrylate/zinc phthalocyanine composite Poly(HEMA/MMA/ZnPc) is described for the first time in this study. The aim of this research is to present possibility of radiation synthesis of the newly zinc phthalocyanine composites as potential candidates for wide range of applications. Gel (%) and swelling for Poly(hydroxyethyl methacrylate) Poly(HEMA) and the based Poly(hydroxyethyl methacrylate/methyl methacrylate) copolymer Poly(HEMA/MMA) with different composition 100/0, 95/5, 90/10 and 80/20 wt % were evaluated. It was found that Poly(HEMA/MMA) copolymer with composition 95/5 wt % characterized by its high swelling property at pH 7.4. The prepared composites I and II Poly(HEMA/MMA/ZnPc) with composition (95/5/1 wt%) and (95/5/1.5 wt%) respectively have been characterized by FTIR and TGA. The effect of gamma irradiation on the chemical properties of composite I was described. It is observed that the Zinc phthalocyanine with low concentration 1 wt % enhance chemical, thermal properties and stabilization against gamma radiation of the prepared composite I. - Highlights: • The preparation of Poly(HEMA/MMA/ZnPc) by radiation forming modified composites. • The low concentration of ZcPc (1 or 1.5 wt %) lead to form outstanding properties. • These composites are a potential candidate for wide range of applications.

Fluid structure interaction simulations of the upper airway in obstructive sleep apnea patients before and after maxillomandibular advancement surgery.

Science.gov (United States)

Chang, Kwang K; Kim, Ki Beom; McQuilling, Mark W; Movahed, Reza

2018-06-01

The purpose of this study was to analyze pharyngeal airflow using both computational fluid dynamics (CFD) and fluid structure interactions (FSI) in obstructive sleep apnea patients before and after maxillomandibular advancement (MMA) surgery. The airflow characteristics before and after surgery were compared with both CFD and FSI. In addition, the presurgery and postsurgery deformations of the airway were evaluated using FSI. Digitized pharyngeal airway models of 2 obstructive sleep apnea patients were generated from cone-beam computed tomography scans before and after MMA surgery. CFD and FSI were used to evaluate the pharyngeal airflow at a maximum inspiration rate of 166 ml per second. Standard steady-state numeric formulations were used for airflow simulations. Airway volume increased, pressure drop decreased, maximum airflow velocity decreased, and airway resistance dropped for both patients after the MMA surgery. These findings occurred in both the CFD and FSI simulations. The FSI simulations showed an area of marked airway deformation in both patients before surgery, but this deformation was negligible after surgery for both patients. Both CFD and FSI simulations produced airflow results that indicated less effort was needed to breathe after MMA surgery. The FSI simulations demonstrated a substantial decrease in airway deformation after surgery. These beneficial changes positively correlated with the large improvements in polysomnography outcomes after MMA surgery. Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Rare RNF213 variants in the C-terminal region encompassing the RING-finger domain are associated with moyamoya angiopathy in Caucasians.

Science.gov (United States)

Guey, Stéphanie; Kraemer, Markus; Hervé, Dominique; Ludwig, Thomas; Kossorotoff, Manoëlle; Bergametti, Françoise; Schwitalla, Jan Claudius; Choi, Simone; Broseus, Lucile; Callebaut, Isabelle; Genin, Emmanuelle; Tournier-Lasserve, Elisabeth

2017-08-01

Moyamoya angiopathy (MMA) is a cerebral angiopathy affecting the terminal part of internal carotid arteries. Its prevalence is 10 times higher in Japan and Korea than in Europe. In East Asian countries, moyamoya is strongly associated to the R4810K variant in the RNF213 gene that encodes for a protein containing a RING-finger and two AAA+ domains. This variant has never been detected in Caucasian MMA patients, but several rare RNF213 variants have been reported in Caucasian cases. Using a collapsing test based on exome data from 68 European MMA probands and 573 ethnically matched controls, we showed a significant association between rare missense RNF213 variants and MMA in European patients (odds ratio (OR)=2.24, 95% confidence interval (CI)=(1.19-4.11), P=0.01). Variants specific to cases had higher pathogenicity predictive scores (median of 24.2 in cases versus 9.4 in controls, P=0.029) and preferentially clustered in a C-terminal hotspot encompassing the RING-finger domain of RNF213 (P<10 -3 ). This association was even stronger when restricting the analysis to childhood-onset and familial cases (OR=4.54, 95% CI=(1.80-11.34), P=1.1 × 10 -3 ). All clinically affected relatives who were genotyped were carriers. However, the need for additional factors to develop MMA is strongly suggested by the fact that only 25% of mutation carrier relatives were clinically affected.

Technical and Economic Comparison MOB location versus Bergermeer Drilling Site. Justification of the Financial section in the Environmental Impact Report (MER)

International Nuclear Information System (INIS)

Dekker, W.; Azeem Khan, F.

2009-09-01

The Environmental Impact Report for the gas storage location Bergermeer has selected the MOB area (mobilization complex or storage site of the Dutch Ministry of Defense) in Bergen as the most environment-friendly alternative (MMA) for the well area. TAQA asked SGS to elaborate the technical and financial aspects of the MMA alternative and to compare them to the preferred alternative. [nl

Remediation of Organic and Inorganic Arsenic Contaminated Groundwater using a Nonocrystalline TiO2 Based Adsorbent

Energy Technology Data Exchange (ETDEWEB)

Jing, C.; Meng, X; Calvache, E; Jiang, G

2009-01-01

A nanocrystalline TiO2-based adsorbent was evaluated for the simultaneous removal of As(V), As(III), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in contaminated groundwater. Batch experimental results show that As adsorption followed pseudo-second order rate kinetics. The competitive adsorption was described with the charge distribution multi-site surface complexation model (CD-MUSIC). The groundwater containing an average of 329 ?g L-1 As(III), 246 ?g L-1 As(V), 151 ?g L-1 MMA, and 202 ?g L-1 DMA was continuously passed through a TiO2 filter at an empty bed contact time of 6 min for 4 months. Approximately 11 000, 14 000, and 9900 bed volumes of water had been treated before the As(III), As(V), and MMA concentration in the effluent increased to 10 ?g L-1. However, very little DMA was removed. The EXAFS results demonstrate the existence of a bidentate binuclear As(V) surface complex on spent adsorbent, indicating the oxidation of adsorbed As(III). A nanocrystalline TiO2-based adsorbent could be used for the simultaneous removal of As(V), As(III), MMA, and DMA in contaminated groundwater.

Urinary arsenic speciation profile in ethnic group of the Atacama desert (Chile) exposed to variable arsenic levels in drinking water.

Science.gov (United States)

Yáñez, Jorge; Mansilla, Héctor D; Santander, I Paola; Fierro, Vladimir; Cornejo, Lorena; Barnes, Ramón M; Amarasiriwardena, Dulasiri

2015-01-01

Ethnic groups from the Atacama Desert (known as Atacameños) have been exposed to natural arsenic pollution for over 5000 years. This work presents an integral study that characterizes arsenic species in water used for human consumption. It also describes the metabolism and arsenic elimination through urine in a chronically exposed population in northern Chile. In this region, water contained total arsenic concentrations up to 1250 μg L(-1), which was almost exclusively As(V). It is also important that this water was ingested directly from natural water sources without any treatment. The ingested arsenic was extensively methylated. In urine 93% of the arsenic was found as methylated arsenic species, such as monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. The original ingested inorganic species [As(V)], represent less than 1% of the total urinary arsenic. Methylation activity among individuals can be assessed by measuring primary [inorganic As/methylated As] and secondary methylation [MMA/DMA] indexes. Both methylation indexes were 0.06, indicating a high biological converting capability of As(V) into MMA and then MMA into DMA, compared with the control population and other arsenic exposed populations previously reported.

Cyclodextrin-containing hydrogels as an intraocular lens for sustained drug release.

Directory of Open Access Journals (Sweden)

Xiao Li

Full Text Available To improve the efficacy of anti-inflammatory factors in patients who undergo cataract surgery, poly(2-hydroxyethyl methacrylate-co-methyl methacrylate (p(HEMA-co-MMA hydrogels containing β-cyclodextrin (β-CD (pHEMA/MMA/β-CD were designed and prepared as intraocular lens (IOLs biomaterials that could be loaded with and achieve the sustained release of dexamethasone. A series of pHEMA/MMA/β-CD copolymers containing different ratios of β-CD (range, 2.77 to 10.24 wt.% were obtained using thermal polymerization. The polymers had high transmittance at visible wavelengths and good biocompatibility with mouse connective tissue fibroblasts. Drug loading and release studies demonstrated that introducing β-CD into hydrogels increased loading efficiency and achieved the sustained release of the drug. Administering β-CD via hydrogels increased the equilibrium swelling ratio, elastic modulus and tensile strength. In addition, β-CD increased the hydrophilicity of the hydrogels, resulting in a lower water contact angle and higher cellular adhesion to the hydrogels. In summary, pHEMA/MMA/β-CD hydrogels show great potential as IOL biomaterials that are capable of maintaining the sustained release of anti-inflammatory drugs after cataract surgery.

Effect of hypotension and carbon dioxide changes in an improved genuine closed cranial window rat model

DEFF Research Database (Denmark)

Petersen, K A; Dyrby, Lone; Williamson, D

2005-01-01

The genuine closed cranial window model, in which the thinned parietal bone constitutes the covering of the preparation, has contributed to a better understanding of the pathophysiological mechanisms in migraine. In its present form, only measurements of the middle meningeal artery (MMA) are perf......The genuine closed cranial window model, in which the thinned parietal bone constitutes the covering of the preparation, has contributed to a better understanding of the pathophysiological mechanisms in migraine. In its present form, only measurements of the middle meningeal artery (MMA......) are performed. The aim of this study was, in addition, to measure pial artery/arteriole (PA) diameter and cortical cerebral blood flux in the same cranial window. The model was evaluated by studying the effects of hypotension and changes in arterial carbon dioxide pressure (PaCO2), because these parameters......-induced hypotension (-64+/-0.8 mmHg) caused an increase of MMA diameter of 11.8+/-8.4%, PA diameter of 61.2+/-7.7% and a decrease in LCBF(Flux) of -36.4+/-2.5%. The decrease in blood pressure did not significantly change the MMA (P=0.38); however, the PA diameter and the LCBF(Flux) were affected (P

The actions of the social insurance agency regarding long-term sickness absentees before and after a medical assessment--a study of 384 case files.

Science.gov (United States)

Marklund, Staffan; Lundh, Göran; Gustafsson, Klas; Linder, Jürgen; Svedberg, Pia; Alexanderson, Kristina

2015-01-01

The purpose of this article is to investigate actions taken by the Social Insurance Agency (SIA) for long-term sickness absentees and possible associations of this with future sick leave or disability pension. For 384 long-term sickness absentees who had had a multidisciplinary medical assessment (MMA) during 2001-2006, three types of data were obtained: (1) case file information about SIA actions, (2) suggested rehabilitation measures from the MMA and (3) sickness absence and disability pension data. Most individuals had been subject to a range of actions by the SIA. Sixty percent had been invited to a coordination meeting, and half of those who assessed by the MMA for vocational rehabilitation were approved to get it by the SIA. Few SIA actions were associated with full or partial return to work. Although the studied individuals had been on sick leave for a long time, the number of SIA actions related to vocational rehabilitation was limited and came late in the sick-leave spell. The information from the MMA was often not used as a basis for further SIA action and seldom resulted in return to work. The positive MMA views on the potential of vocational rehabilitation were not met by SIA actions. Suggestions on vocational rehabilitation from a medical assessment was in many cases not used by the social insurance agency in relationship to long-term sickness absentees. Active rehabilitation measures by the social insurance agency were few and came late in the sickness absence process. Few of the activities taken by the social insurance agency enhanced return to work.

Forehead Augmentation with a Methyl Methacrylate Onlay Implant Using an Injection-Molding Technique

Directory of Open Access Journals (Sweden)

Dong Kwon Park

2013-09-01

Full Text Available Background The forehead, which occupies about one third of the face, is one of the majordeterminants of a feminine or masculine look. Various methods have been used for the augmentationof the forehead using autologous fat grafts or alloplastic materials. Methylmethacrylate(MMA is the most appropriate material for augmentation of the forehead, and we have usedan injection-molding technique with MMA to achieve satisfactory results.Methods Under local anesthesia with intravenous (IV sedation, an incision was made onthe scalp and a meticulous and delicate subperiosteal dissection was then performed. MMAmonomers and polymers were mixed, the dough was injected into the space created, andmanual molding was performed along with direct inspection. This surgery was indicated forpatients who wanted to correct an unattractive appearance by forehead augmentation. Everypatient in this study visited our clinics 3 months after surgery to evaluate the results. Wejudged the postoperative results in terms of re-operation rates caused by the dissatisfactionof the patients and complications.Results During a 13-year period, 516 patients underwent forehead augmentation with MMA.With the injection-molding technique, the inner surface of the MMA implant is positionedclose to the underlying frontal bone, which minimizes the gap between the implant and bone.The borders of the implant should be tapered sufficiently until no longer palpable or visible.Only 28 patients (5.4% underwent a re-operation due to an undesirable postoperative appearance.Conclusions The injection-molding technique using MMA is a simple, safe, and ideal methodfor the augmentation of the forehead.

[Study of relationship between arsenic methylation and skin lesion in a population with long-term high arsenic exposure].

Science.gov (United States)

Su, Liqin; Cheng, Yibin; Lin, Shaobin; Wu, Chuanye

2007-05-01

To investigate the difference of arsenic metabolism in populations with long-term high arsenic exposure and explore the relationship between arsenic metabolism diversity and skin lesion. 327 residents in an arsenic polluted village were voluntarily enrolled in this study. Questionnaire survey and medical examination were carried out to learn basic information and detect skin lesions. Urinary inorganic and methylated arsenic were speciated by high performance liquid chromatography combined with hydride-generation atomic fluorescence spectrometry. Total arsenic concentration in hair was determined with DDC-Ag method. Hair arsenic content of studied polutions was generally high, but no significant difference were found among the studied four groups. MMA and DMA concentration in urine increased with studied polution age, and were positively related with skin lesion grade. The relative proportion of MMA in serious skin lesion group was significantly higher than in other 3 groups, while DMA/MMA ratio was significantly lower than control and mild group. The relative proportion of MMA was positively related with skin lesion grade, DMA/ MMA ratio was negatively related with skin lesion grade. Males could have higher arsenic cumulation and lower methylation capacity than those of females. The population of above 40 years old may have higher methylation capacity than those of adults below 40yeas old. Smokers and drinkers seemed lower methylation capacity than those of non-smokers and non-drinkers respectively. The methylation of arsenic could affect by several factors, including age gender, smoking and drinking. Arsenic methylation copacity mey be associated with skin lesion induced by arsenic exposure.

Radical polymerization in holographic grating formation in PQ-PMMA photopolymer part II: Consecutive exposure and dark decay

Science.gov (United States)

Yu, Dan; Liu, Hongpeng; Geng, Yaohui; Wang, Weibo; Zhao, Yuanyuan

2014-11-01

Photochemical radical polymerization in phenathrenequinone doped poly(methyl methacrylate) photopolymer are investigated theoretically and experimentally under consecutive exposure. The detailed photochemical mechanisms are analyzed. Based on the rate equations of photochemical reactions, the diffusion models with nonlocal response are proposed to describe the kinetic process of radical polymerization and the significance of photochemical processes for the grating formation. In experiments, the temporal evolution of diffraction efficiency in grating formation is measured under consecutive exposure and after exposure. The percentages of these radical polymerizations, namely the polymerization of PQ with matrix, the bimolecular combination of MMA molecules, and the disproportionation of MMA molecules, are extracted quantitatively by comparing theory with experiments. It is indicated that the polymerization of PQ with matrix is primary photochemical process which dominated the grating formation under consecutive exposure. In this period, the contribution of chain polymerization of MMA radicals is weak for the grating formation. After reaching the peak values of grating strength, the influence of the free MMA molecules and photoproduct macromolecules on the grating decay is discussed in a long-term period. The diffusion coefficients of MMA and photoproduct are extracted by fitting the curves using double exponential function. MMA’s diffusion contributed to the fast decay process of grating after exposure and photoproduct’s diffusion contributed to the slow and long decay of grating. The results break previous understanding about the diffusion of single photoproduct macromolecules lead to the dark decay of grating. This investigation can provide a significant foundation for improving modulation depth and long-term stability by photochemical mechanism.

Arsenic methylation capacity is associated with breast cancer in northern Mexico.

Science.gov (United States)

López-Carrillo, Lizbeth; Hernández-Ramírez, Raúl Ulises; Gandolfi, A Jay; Ornelas-Aguirre, José Manuel; Torres-Sánchez, Luisa; Cebrian, Mariano E

2014-10-01

Exposure to environmental contaminants, dietary factors and lifestyles may explain worldwide different breast cancer (BC) incidence. Inorganic arsenic (iAs) in the drinking water is a concern in many regions, such as northern Mexico. Studies in several countries have associated the proportion of urinary monomethylarsenic (%MMA) with increased risks for many As-related diseases, including cancer. To investigate the potential relationships between the risk of BC and the capacity to methylate iAs, a hospital-based case-control study (1016 cases/1028 controls) was performed in northern Mexico. Women were directly interviewed about their reproductive histories. The profile of As metabolites in urine was determined by HPLC-ICP-MS and methylation capacity was assessed by metabolite percentages and indexes. Total urinary As, excluding arsenobetaine (TAs-AsB), ranged from 0.26 to 303.29μg/L. Most women (86%) had TAs-AsB levels below As biological exposure index (35μg/L). Women with higher %MMA and/or primary methylation index (PMI) had an increased BC risk (%MMA ORQ5vs.Q1=2.63; 95%CI 1.89,3.66; p for trend 42, 95%CI 0.31,0.59, p for trend iAs nor total methylation index was associated to BC risk. Inter-individual variations in iAs metabolism may play a role in BC carcinogenesis. Women with higher capacity to methylate iAs to MMA and/or a lower capacity to further methylate MMA to DMA were at higher BC risk. Copyright © 2014 Elsevier Inc. All rights reserved.

The-Abstraction-Hierarchy-based Mobile PC Display Design for NPP Maintenance

International Nuclear Information System (INIS)

Kim, In; Kim, Bo Gyung; Seong, Poong Hyun; Ha, Jun Su

2010-01-01

Recently, the importance of effective maintenance in nuclear power plants (NPPs) has been emphasized and research into effective maintenance by adopting mobile maintenance aids (MMAs) have been attempted. For improved and effective use of an MMA display design method based on abstraction hierarchy (AH) is proposed and its design considerations are discussed in this study. Six levels of abstraction hierarchy are proposed in this paper to classify the maintenance information. By classifying and organizing maintenance information using AH, maintenance information can be used effectively by users with either high or low levels of expertise. When information classification has been finished, the information for MMA design is selected and designed. With the considerations of MMA design analysis and guidelines, AH-based MMA is designed for the maintenance tasks. An experiment is conducted using the AH-based MMA in order to estimate the effectiveness of the proposed method for the maintenance tasks and to identify design considerations to enhance the proposed MMAs. The result indicated that an AH-based manual was more effective than a conventional manual in terms of task completion time and number of errors. The workload for the AH-based manual was estimated less than the conventional manual for subjects with low level of expertise. As the level of expertise increases, subjects tended to follow more abstract information while the number of navigations decreased. It is believed that when mobile devices become pervasive in NPP maintenance fields, AH-model applied MMAs can be used as an effective maintenance supporting tool

Recent surface displacements in the Upper Rhine Graben — Preliminary results from geodetic networks

Science.gov (United States)

Fuhrmann, Thomas; Heck, Bernhard; Knöpfler, Andreas; Masson, Frédéric; Mayer, Michael; Ulrich, Patrice; Westerhaus, Malte; Zippelt, Karl

2013-08-01

Datasets of the GNSS Upper Rhine Graben Network (GURN) and the national levelling networks in Germany, France and Switzerland are investigated with respect to current surface displacements in the Upper Rhine Graben (URG) area. GURN consists of about 80 permanent GNSS (Global Navigation Satellite Systems) stations. The terrestrial levelling network comprises 1st and 2nd order levelling lines that have been remeasured at intervals of roughly 25 years, starting in 1922. Compared to earlier studies national institutions and private companies made available raw data, allowing for consistent solutions for the URG region. We focussed on the southern and eastern parts of the investigation area. Our preliminary results show that the levelling and GNSS datasets are sensitive to resolve small surface displacement rates down to an order of magnitude of 0.2 mm/a and 0.4 mm/a, respectively. The observed horizontal velocity components for a test region south of Strasbourg, obtained from GNSS coordinate time series, vary around 0.5 mm/a. The results are in general agreement with interseismic strain built-up in a sinistral strike-slip regime. Since the accuracy of the GNSS derived vertical component is insufficient, data of precise levelling networks is used to determine vertical displacement rates. More than 75% of the vertical rates obtained from a kinematic adjustment of 1st order levelling lines in the eastern part of URG vary between - 0.2 mm/a and + 0.2 mm/a, indicating that this region behaves stable. Higher rates up to 0.5 mm/a in a limited region south of Freiburg are in general agreement with active faulting. We conclude that both networks deliver stable results that reflect real surface movements in the URG area. We note, however, that geodetically observed surface displacements generally result from a superposition of different effects, and that a separation in tectonic and non-tectonic processes needs additional information and expertise.

Association of Low-Moderate Arsenic Exposure and Arsenic Metabolism with Incident Diabetes and Insulin Resistance in the Strong Heart Family Study.

Science.gov (United States)

Grau-Perez, Maria; Kuo, Chin-Chi; Gribble, Matthew O; Balakrishnan, Poojitha; Jones Spratlen, Miranda; Vaidya, Dhananjay; Francesconi, Kevin A; Goessler, Walter; Guallar, Eliseo; Silbergeld, Ellen K; Umans, Jason G; Best, Lyle G; Lee, Elisa T; Howard, Barbara V; Cole, Shelley A; Navas-Acien, Ana

2017-12-20

High arsenic exposure has been related to diabetes, but at low-moderate levels the evidence is mixed. Arsenic metabolism, which is partly genetically controlled and may rely on certain B vitamins, plays a role in arsenic toxicity. We evaluated the prospective association of arsenic exposure and metabolism with type 2 diabetes and insulin resistance. We included 1,838 American Indian men and women free of diabetes (median age, 36 y). Arsenic exposure was assessed as the sum of inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) urine concentrations (ΣAs). Arsenic metabolism was evaluated by the proportions of iAs, MMA, and DMA over their sum (iAs%, MMA%, and DMA%). Homeostasis model assessment for insulin resistance (HOMA2-IR) was measured at baseline and follow-up visits. Incident diabetes was evaluated at follow-up. Median ΣAs, iAs%, MMA%, and DMA% was 4.4 μg/g creatinine, 9.5%, 14.4%, and 75.6%, respectively. Over 10,327 person-years of follow-up, 252 participants developed diabetes. Median HOMA2-IR at baseline was 1.5. The fully adjusted hazard ratio [95% confidence interval (CI)] for incident diabetes per an interquartile range increase in ΣAs was 1.57 (95% CI: 1.18, 2.08) in participants without prediabetes at baseline. Arsenic metabolism was not associated with incident diabetes. ΣAs was positively associated with HOMA2-IR at baseline but negatively with HOMA2-IR at follow-up. Increased MMA% was associated with lower HOMA2-IR when either iAs% or DMA% decreased. The association of arsenic metabolism with HOMA2-IR differed by B-vitamin intake and AS3MT genetics variants. Among participants without baseline prediabetes, arsenic exposure was associated with incident diabetes. Low MMA% was cross-sectional and prospectively associated with higher HOMA2-IR. Research is needed to confirm possible interactions of arsenic metabolism with B vitamins and AS3MT variants on diabetes risk. https://doi.org/10.1289/EHP2566.

Speciation of arsenic in biological samples.

Science.gov (United States)

Mandal, Badal Kumar; Ogra, Yasumitsu; Anzai, Kazunori; Suzuki, Kazuo T

2004-08-01

Speciation of arsenicals in biological samples is an essential tool to gain insight into its distribution in tissues and its species-specific toxicity to target organs. Biological samples (urine, hair, fingernail) examined in the present study were collected from 41 people of West Bengal, India, who were drinking arsenic (As)-contaminated water, whereas 25 blood and urine samples were collected from a population who stopped drinking As contaminated water 2 years before the blood collection. Speciation of arsenicals in urine, water-methanol extract of freeze-dried red blood cells (RBCs), trichloroacetic acid treated plasma, and water extract of hair and fingernail was carried out by high-performance liquid chromatography (HPLC)-inductively coupled argon plasma mass spectrometry (ICP MS). Urine contained arsenobetaine (AsB, 1.0%), arsenite (iAs(III), 11.3), arsenate (iAs(V), 10.1), monomethylarsonous acid (MMA(III), 6.6), monomethylarsonic acid (MMA(V), 10.5), dimethylarsinous acid (DMA(III), 13.0), and dimethylarsinic acid (DMA(V), 47.5); fingernail contained iAs(III) (62.4%), iAs(V) (20.2), MMA(V) (5.7), DMA(III) (8.9), and DMA(V) (2.8); hair contained iAs(III) (58.9%), iAs(V) (34.8), MMA(V) (2.9), and DMA(V) (3.4); RBCs contained AsB (22.5%) and DMA(V) (77.5); and blood plasma contained AsB (16.7%), iAs(III) (21.1), MMA(V) (27.1), and DMA(V) (35.1). MMA(III), DMA(III), and iAs(V) were not found in any plasma and RBCs samples, but urine contained all of them. Arsenic in urine, fingernails, and hair are positively correlated with water As, suggesting that any of these measurements could be considered as a biomarker to As exposure. Status of urine and exogenous contamination of hair urgently need speciation of As in these samples, but speciation of As in nail is related to its total As (tAs) concentration. Therefore, total As concentrations of nails could be considered as biomarker to As exposure in the endemic areas.

Speciation of arsenic in biological samples

International Nuclear Information System (INIS)

Mandal, Badal Kumar; Ogra, Yasumitsu; Anzai, Kazunori; Suzuki, Kazuo T.

2004-01-01

Speciation of arsenicals in biological samples is an essential tool to gain insight into its distribution in tissues and its species-specific toxicity to target organs. Biological samples (urine, hair, fingernail) examined in the present study were collected from 41 people of West Bengal, India, who were drinking arsenic (As)-contaminated water, whereas 25 blood and urine samples were collected from a population who stopped drinking As contaminated water 2 years before the blood collection. Speciation of arsenicals in urine, water-methanol extract of freeze-dried red blood cells (RBCs), trichloroacetic acid treated plasma, and water extract of hair and fingernail was carried out by high-performance liquid chromatography (HPLC)-inductively coupled argon plasma mass spectrometry (ICP MS). Urine contained arsenobetaine (AsB, 1.0%), arsenite (iAs III , 11.3), arsenate (iAs V , 10.1), monomethylarsonous acid (MMA III , 6.6), monomethylarsonic acid (MMA V , 10.5), dimethylarsinous acid (DMA III , 13.0), and dimethylarsinic acid (DMA V , 47.5); fingernail contained iAs III (62.4%), iAs V (20.2), MMA V (5.7), DMA III (8.9), and DMA V (2.8); hair contained iAs III (58.9%), iAs V (34.8), MMA V (2.9), and DMA V (3.4); RBCs contained AsB (22.5%) and DMA V (77.5); and blood plasma contained AsB (16.7%), iAs III (21.1), MMA V (27.1), and DMA V (35.1). MMA III , DMA III , and iAs V were not found in any plasma and RBCs samples, but urine contained all of them. Arsenic in urine, fingernails, and hair are positively correlated with water As, suggesting that any of these measurements could be considered as a biomarker to As exposure. Status of urine and exogenous contamination of hair urgently need speciation of As in these samples, but speciation of As in nail is related to its total As (tAs) concentration. Therefore, total As concentrations of nails could be considered as biomarker to As exposure in the endemic areas

A multisensory, multicognitive approach to teaching pronunciation

Directory of Open Access Journals (Sweden)

Edward Y. Odisho

2007-01-01

Full Text Available The Multisensory, Multicognitive Approach (MMA introduced in this paper is premised on the belief that the seat of language is in the brain prior to its physical manifestation in the form of speech being in the mouth. Hence, in teaching pronunciation, the identity of speech as a cognitive entity prior to being a physical one should be seriously considered in relevant language learning and teaching situations – more so in L2 situations than in L1. The traditional assumption that the ideal and the exclusive sensory modality of teaching pronunciation is the auditory modality is no longer acceptable because a holistic view of speech – in production, transmission and perception – manifests itself not only via the auditory sensory modality, but also equally significantly via the visual and tactile-kinesthetic sensory modalities. It is due to this fact that MMA is described as multisensory, a fact that determines the diversified auditory, visual and tactile-kinesthetic implementational techniques needed for effective and efficient teaching of pronunciation especially to adults. Equally importantly, the multicognitive nature of MMA requires the manipulation of diversified cognitive processes in the form of thinking, associating, analyzing, synthesizing, comparing, contrasting etc… for implementation. According to MMA, the teaching of pronunciation becomes more of a multifaceted educational process than a mere repeat-after-me mechanical parroting of speech sounds. Such an approach requires more effort on the part of the instructor and learner and a stronger collaboration between them through the diversification of teaching and learning styles, respectively. Certainly, MMA requires more time to implement in classroom situations, but the time spent is worth it. MMA is no longer a single technique or drill that tackles one sound at a time; instead, it is a joint selection of cognitive and sensory techniques that are applied concurrently to

Boxing and mixed martial arts: preliminary traumatic neuromechanical injury risk analyses from laboratory impact dosage data.

Science.gov (United States)

Bartsch, Adam J; Benzel, Edward C; Miele, Vincent J; Morr, Douglas R; Prakash, Vikas

2012-05-01

In spite of ample literature pointing to rotational and combined impact dosage being key contributors to head and neck injury, boxing and mixed martial arts (MMA) padding is still designed to primarily reduce cranium linear acceleration. The objects of this study were to quantify preliminary linear and rotational head impact dosage for selected boxing and MMA padding in response to hook punches; compute theoretical skull, brain, and neck injury risk metrics; and statistically compare the protective effect of various glove and head padding conditions. An instrumented Hybrid III 50th percentile anthropomorphic test device (ATD) was struck in 54 pendulum impacts replicating hook punches at low (27-29 J) and high (54-58 J) energy. Five padding combinations were examined: unpadded (control), MMA glove-unpadded head, boxing glove-unpadded head, unpadded pendulum-boxing headgear, and boxing glove-boxing headgear. A total of 17 injury risk parameters were measured or calculated. All padding conditions reduced linear impact dosage. Other parameters significantly decreased, significantly increased, or were unaffected depending on padding condition. Of real-world conditions (MMA glove-bare head, boxing glove-bare head, and boxing glove-headgear), the boxing glove-headgear condition showed the most meaningful reduction in most of the parameters. In equivalent impacts, the MMA glove-bare head condition induced higher rotational dosage than the boxing glove-bare head condition. Finite element analysis indicated a risk of brain strain injury in spite of significant reduction of linear impact dosage. In the replicated hook punch impacts, all padding conditions reduced linear but not rotational impact dosage. Head and neck dosage theoretically accumulates fastest in MMA and boxing bouts without use of protective headgear. The boxing glove-headgear condition provided the best overall reduction in impact dosage. More work is needed to develop improved protective padding to minimize

Amnioinfusion for relief of recurrent severe and moderate variable decelerations in labor.

Science.gov (United States)

Regi, Annie; Alexander, Nancy; Jose, Ruby; Lionel, Jessie; Varghese, Lilly; Peedicayil, Abraham

2009-05-01

To determine whether intrapartum amnioinfusion (AI) relieves recurrent moderate and severe variable decelerations in laboring women with clear or grade I meconium-stained amniotic fluid and reduces cesarean section rate for fetal distress. A randomized controlled trial was conducted in labor unit of Christian Medical College Hospital, Vellore, India, between October 2003 and September 2004. Women were randomized to receive AI (group I) and not to receive it (group II). A total of 150 women (75 in each group) were included in the study. There was significant relief of variable decelerations in group I and no difference in overall cesarean section rate but significant reduction in cesarean section rate for fetal distress in group I, and significant reduction in cesarean section rate for fetal distress in nulliparous women of group I. Neonatal acidemia was also significantly reduced in the nulliparous women receiving AI. The duration of maternal postpartum hospital stay was significantly reduced in group I. There were no adverse maternal or neonatal outcomes. AI was a beneficial therapeutic intervention in women patients showing fetal distress in first stage of labor, and it reduced cesarean section for fetal distress and neonatal acidemia.

The Evaluation of Relationship between Spirometric Disorders and Methyl methacrylate in Dental Laboratories Personnel

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E. Nadi

2010-04-01

Full Text Available Introduction & Objective: Methyl methacrylate (MMA, as a monomer of acrylic resin that has a wide variety of usages in denture fabrication, is considered as an air pollution indicator in the laboratories. Occupational exposure to these compound vapors can cause respiratory hypersensitivity, occupational asthma, eye and skin irritation and Allergic Contact Dermatitis (ACD. Therefore control of MMA exposure may promote the personnel’s health. The aim of this study was to determine the relationship between spirometric disorders and methyl methacrylate in dental laboratories personnel.. Materials & Methods: In this case control study, exposure of time-weighted average (TWA and short-term exposure level (STEL were measured with MMA vapors in 39 randomly selected male employee (case group in 25 denture fabrication laboratories in Hamadan city. The air samples were collected by sorbent tubes containing chromosorb (XAD2( and analyzed by gas chromatograph equipped with FID detector based on NIOSH method. In addition 30 men whitout occupational exposure to air pollutants (control group were selected to compare the variation of spirometric parameters. Spirometric parameters of the case and control groups such as FVC, FEV1, FEV1/FVC and FEF25-75 were measured by Vitalograph spirometer (model: 2120 on ATS method, after the standard questionnaire of respiratory diseases had been completed during an interview and medical examination..Results: The mean of MMA concentration was 132.87 ± 220.67 ppm for STEL and 1.95 ± 3.59 ppm for TWA.The relationship between MMA concentration in the STEL and TWA exposures was significant (P<0.05 and the relationship between MMA concentration and ventilation was significant just for STEL. In this study no relationship between MMA concentration and spirometric parameters in both STEL and TWA exposures was found. Also there was no significant difference between spirometric parameters of the case group and normal values of the

Dinámicas de ocupación urbana del anillo verde metropolitano de Madrid = Urban occupation dynamics of Madrid´s Metropolitan Greenbelt

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Lourdes Jiménez Garcinuño

2017-05-01

ABSTRACT: The Metropolitan Greenbelt was defined by the 1963 Master Plan for the Madrid Metropolitan Area (MMA, following established international models of urban development, as the structural framework of the MMA, the principal open space within its network of open spaces and a public area of recreation and contact with nature for the residents of Madrid. However, it had become a reserve of land in which various alliances between the institutional authorities and the dominant social class, have been operating on the margin of the original plan, exposing a scarcity of legal and cultural resources for the safeguarding of common interests, and in which the geographical and natural characteristics of the territory itself have come to play an influential role in the functional specialization and spatial segregation of the MMA.

A Design of Innovative Engineering Drawing Teaching Materials

Science.gov (United States)

Mujiarto; Djohar, A.; Komaro, M.

2018-02-01

Good teaching is influenced by several things such as effective school leaders and skilled teachers who are able to use information communication technology as a medium of learning. The purpose of this research in general is to develop innovative teaching materials in the form of multimedia animation for engineering drawing in the field of technology and engineering at vocational high school. Research method used research and development (research and development / R & D). The results showed that the E-book Multimedia Animation Engineering Drawing (E-MMAED) is easy to possess and contains complete material. Students stated that the use of E-MMAED adds to learning motivation and improves learning outcomes (student competencies). We recommend that teachers apply E-MMAED as a learning medium and create other innovations to improve student competences.

Preparation of poly(methyl methacrylate) microcapsules by in situ polymerization on the surface of calcium carbonate particles.

Science.gov (United States)

Sato, Katsuhiko; Nakajima, Tatsuya; Anzai, Jun-ichi

2012-12-01

Poly(methyl methacrylate) (PMMA) microcapsules were prepared by the in situ polymerization of methyl methacrylate (MMA) and N,N'-methylenebisacrylamide on the surface of calcium carbonate (CaCO(3)) particles, followed by the dissolution of the CaCO(3) core in ethylenediaminetetraacetic acid solution. The microcapsules were characterized using fluorescence microscopy, atomic force microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. The average sizes of the CaCO(3) particles and PMMA capsules were 3.8±0.6 and 4.0±0.6 μm, respectively. A copolymer consisting of MMA and rhodamine B-bearing MMA was also used to prepare microcapsules for fluorescent microscopy observations. Fluorescein isothiocyanate-labeled bovine serum albumin was enclosed in the PMMA microcapsules and its release properties were studied. Copyright © 2012 Elsevier Inc. All rights reserved.

Structural effects of a light emitting copolymer having perylene moieties in the side chain on the electroluminescent characteristics

International Nuclear Information System (INIS)

Lee, Chang Ho; Ryu, Seung Hoon; Jang, Hee Dong; Oh, Se Young

2004-01-01

We have synthesized a novel side chain light emitting copolymer. The side chain light emitting copolymer has a perylene moiety as an emitting unit and methylmethacrylate (MMA) as a spacer to decrease the concentration quenching of light emitting site in the polymer intrachain. These polymers are very soluble in most organic solvents such as monochlorobenzene, tetrahydrofuran, chloroform and benzene. The single-layered electroluminescent (EL) device consisting of ITO/carrier transporting copolymer and light emitting copolymer/Al was manufactured. The carrier transporting copolymer has triphenylamine moiety as a hole transporting unit and triazine moiety as an electron transporting unit in the polymer side chain. This device exhibits maximum external quantum efficiency when the MMA contents of light emitting copolymer is 30 wt.%. In particular, the device emits more blue light as MMA contents increase

A silicone rubber based composites using n-octadecane/poly (styrene-methyl methacrylate) microcapsules as energy storage particle

Science.gov (United States)

Wu, W. L.; Chen, Z.

A phase-change energy-storage material, silicone rubber (SR) coated n-octadecane/poly (styrene-methyl methacrylate) (SR/OD/P(St-MMA)) microcapsule composites, was prepared by mixing SR and OD/P(St-MMA) microcapsules. The microcapsule content and silicone rubber coated method were investigated. The morphology and thermal properties of the composites were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TG), differential scanning calorimetry (DSC) and heat storage properties. The results showed that the thermal and mechanical properties of SR/OD/P(St-MMA) composites were excellent when the microcapsules were coated with room temperature vulcanized silicone rubber (RTVSR), of which content was 2 phr (per hundred rubber). The enthalpy value of the composites was 67.6 J g-1 and the composites were found to have good energy storage function.

DYE-SENSITIZED PHOTOLYSIS OF o-Cl-HEXAARYLBIIMIDAZOLE AND PHOTOPOLYMERIZATION KINETICS STUDY OF THE LONG WAVE-LENGTH DYE/HEXAARYLBIIMIDAZOLE SYSTEMS

Institute of Scientific and Technical Information of China (English)

Fang Gao; Chun-ying Zhao; Li-dong Li; Shu-jing Feng; Yong-yuan Yang

2000-01-01

o-Chloro-hexaarylbiimidazole (o-Cl-HABI) can be sensitized efficiently by the dyes 1-ethyl-3'-methyl thiacyanine bromide (C1), 3,3'-diethyl thiacarbocyanine iodide (C2), and cyclopentanone 2,5-bis[2-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)ethylidene] (C3) through electron transfer proceses. When exposed to a xenon lamp (filtered by Pyrex glass),the photosensitive systems composed of o-Cl-HABI and the above dyes can produce free radicals which initiate the polymerization of MMA. The photopolymerization kinetics equation was obtained for the o-Cl-HABI/C2 system, Rp =K [C2]0.75[o-Cl-HABI]0.44[MTA]0.12[MMA]1.0. A comparison of the influence of different dyes on the conversion of MMA photopolymerization was conducted.

Dietary practices in isovaleric acidemia: A European survey

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A. Pinto

2017-09-01

Conclusions: This survey demonstrates wide differences in dietary practice in the management of IVA across European centres. It provides unique dietary data collectively representing European practices in IVA which can be used as a foundation to compare dietary management changes as a consequence of the first E-IMD IVA guidelines availability.

Dietary practices in propionic acidemia: A European survey

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A. Daly

2017-12-01

Conclusions: There was high use of PFAA with intakes of natural protein commonly below WHO/FAO/UNU (2007 safe levels. Optimal dietary management can only be determined by longitudinal, multi-centre, prospective case controlled studies. The metabolic instability of PA and small patient cohorts in each centre ensure that this is a challenging undertaking.

STUDIES ON THE INITIATION MECHANISM OF ORGANIC PEROXIDE AND N-METHACRYLOYLOXYETHYL-N-METHYL ANILINE IN METHYL METHACRYLATE POLYMERIZATION

Institute of Scientific and Technical Information of China (English)

QIU Kunyuan; GUO Dajie; GUO Xinqiu; FENG Xinde

1990-01-01

The initiation mechanism of methyl methacrylate (MMA) polymerization by organic peroxide and polymerizable aromatic tertiary amine such as N-methacryloyloxyethyl-N-methyi aniline (MEMA) binary system has been studied. The kinetics of polymerization of MMA and the ESR spectra of organic peroxide/MEMA system were determined. Based on the ESR study and the end-group analysis by UV spectra of the polymer formed, the initiation mechanism is proposed.

The influence of a whole food vegan diet with Nori algae and wild mushrooms on selected blood parameters.

Science.gov (United States)

Schwarz, Joachim; Dschietzig, Thomas; Schwarz, Jens; Dura, Andreas; Nelle, Esther; Watanabe, Fumio; Wintgens, Karl Florian; Reich, Michael; Armbruster, Franz Paul

2014-01-01

Vegan and vegetarian diets could overcome many diseases of civilization. This study examines whether a whole food vegan diet with Nori algae and wild mushrooms can provide a sufficient quantity of critical nutrients. Five blood samples (Baseline to Time 5) were taken over eight months from 75 subjects (10 vegans without B12 supplementation who consumed Nori algae and wild mushrooms, 20 vegans with supplementation, 40 vegetarians, 5 meat-eaters). Blood was analyzed for blood cell counts, total vitamin B12, holotranscobalamin, homocysteine, methylmalonic acid, vitamin B6, folic acid, ferritin, TSH, zinc, creatinine, vitamin D2 and D3. In the vegan group without supplementation, all means were within the tolerance (holotranscobalamin, homocystein) or normal, except for elevated methylmalonic acid and diminished vitamin D. This group developed significantly higher vitamin D2 levels. The vegan group with B12 supplementation and the vegetarian group showed normal values for all parameters. Vegans following a whole food diet had a borderline supply of vitamin B12. Folic acid, vitamin B6, TSH, iron metabolism, and the blood count were in the normal range. Vegans taking dietary supplements demonstrated satisfactory overall results. An ingestion of sundried mushrooms can contribute to the supply of vitamin D.

Vitamin Status among Breastfed Infants in Bhaktapur, Nepal.

Science.gov (United States)

Ulak, Manjeswori; Chandyo, Ram K; Thorne-Lyman, Andrew L; Henjum, Sigrun; Ueland, Per M; Midttun, Øivind; Shrestha, Prakash S; Fawzi, Wafaie W; Graybill, Lauren; Strand, Tor A

2016-03-08

Vitamin deficiencies are known to be common among infants residing in low- and middle-income countries but relatively few studies have assessed several biochemical parameters simultaneously. The objective of the study was to describe the status of vitamins (A, D, E, B₆, B12 and folate) in breastfed infants. We measured the plasma concentrations of trans retinol, 25 hydroxy vitamin D, α-tocopherol, pyridoxal 5'-phosphate, cobalamin, folate, methylmalonic acid, homocysteine, hemoglobin and C-reactive protein from 467 randomly selected infants. One in five (22%) was deficient in at least one vitamin. Mean (SD) plasma folate concentration was 73 (35) nmol/L, and no infant in the sample was folate deficient. Vitamin B₆ deficiency and vitamin B12 deficiency was found in 22% and 17% of the infants, respectively. Elevated plasma methylmalonic acid or total homocysteine concentration was found in 82% and 62% of infants, respectively. Fifteen percent of infants were vitamin A deficient and 65% were marginally deficient in vitamin A. Fewer than 5% of infants had low plasma vitamin D concentration or vitamin E concentration (α-tocopherol importance of continued supplementation campaigns and support the expansion of food fortification and dietary diversification programs that target children and women in Nepal.

[Diagnosis of neonatal metabolic acidosis by eucapnic pH determination].

Science.gov (United States)

Racinet, C; Richalet, G; Corne, C; Faure, P; Peresse, J-F; Leverve, X

2013-09-01

The identification of a metabolic acidosis is a key criterion for establishing a causal relationship between fetal perpartum asphyxia and neonatal encephalopathy and/or cerebral palsy. The diagnostic criteria currently used (pH and base deficit or lactatemia) are imprecise and non-specific. The study aimed to determine among a low-risk cohort of infants born at term (n = 867), the best diagnostic tool of metabolic acidosis in the cordonal from the following parameters: pH, blood gases and lactate values at birth. The data were obtained from arterial blood of the umbilical cord by a blood gas analyser. The parameter best predicting metabolic analysis was estimated from the partial correlations established between the most relevant parameters. The results showed a slight change in all parameters compared to adult values: acidemia (pH: 7.28 ± 0.01), hypercapnia (56.5 ± 1.59 mmHg) and hyperlactatemia (3.4 ± 0.05 mmol/L). From partial correlation analysis, pCO(2) emerged to be the main contributor of acidemia, while lactatemia was shown to be non-specific for metabolic acidosis. Seven cases (0.81 %) showed a pH less than 7.00 with marked hypercapnia. The correction of this respiratory component by EISENBERG's method led to the eucapnic pH, classifying six out of seven cases as exclusive respiratory acidosis. It has been demonstrated that the criteria from ACOG-AAP for defining a metabolic acidosis are incomplete, imprecise and generating errors in excess. The same is true for lactatemia, whose physiological significance has been completely revised, challenging the misconception of lactic acidosis as a specific marker of hypoxia. It appeared that eucapnic pH was the best way for obtaining a reliable diagnosis of metabolic acidosis. We proposed to adopt a simple decision scheme for determining whether a metabolic acidosis has occurred in case of acidemia less than 7.00. Copyright © 2013. Published by Elsevier SAS.

NMR measurement of identical polymer samples by round robin method. 4. Analysis of composition and monomer sequence distribution in poly(methyl methacrylate-co-acrylonitrile) leading to determinations of monomer reactivity ratios

International Nuclear Information System (INIS)

Hatada, Koichi; Kitayama, Tatsuki; Terawaki, Yoshio

1995-01-01

In order to assess the reliability of NMR measurement of polymers, 1 H and 13 C NMR data for three copolymers of methyl methacrylate (MMA) and acrylonitrile (AN) prepared with AIBN were collected from 46 spectrometers whose resonance frequencies for 1 H NMR measurements ranging from 90 to 500 MHz. 1 H and 13 C NMR spectra were measured in nitrobenzene-d 5 at 110degC and acetonitrile-d 3 at 70degC, respectively. Standard deviations (σ's) for chemical shift measurements of the 1 H and 13 C NMR signals were 0.003-0.008 ppm and 0.03-0.05 ppm, respectively. Compositions of the copolymers were determined from the relative intensities of the signals due to the OCH 3 (MMA) and CH (AN) protons, and the σ values for the determinations were 3.7-9.5%. The compositions determined from 13 C NMR (C = O for MMA unit, CN for AN unit) agreed well with those obtained from 1 H NMR. Monomer reactivity ratios r ij (i,j = 1 or 2) for a penultimate model were determined from monomer feed ratios and triad fractions obtained from the C = O (MMA) and CH (AN) carbon signals. Most of the σ values for r ij determinations were 5-14%. While r 22 and r 12 are nearly equivalent, r 11 and r 21 are significantly different from each other, indicating a possible existence of the penultimate-unit effect in the copolymerization of MMA and AN. Terminal model reactivity ratios, r 1 and r 2 , determined formally from the compositions of three samples by Fineman-Ross method showed large σ values (22-24%). (author)

Determining the Prevalence and Assessing the Severity of Injuries in Mixed Martial Arts Athletes

Science.gov (United States)

2009-01-01

Background Mixed martial arts (MMA) is currently the fastest growing sport in the United States and has recently surpassed boxing as the most popular full contact sport. Due to the physical nature of the sport, MMA is associated with various types of injuries. Objective The purpose of this study was aimed at identifying prevalence and assessing the severity, location, and type of injuries in MMA athletes sustained during MMA related activities in the twelve month period prior to the survey. Methods A total of fifty-five subjects between the ages of 18 to 39 participated in the study. Participants were given a two-part questionnaire to collect demographic and injury data. Results Two hundred seven injuries were reported in the study. Low belt ranks had significantly more injuries more than any other belt rank, resulting in more than two times higher injury rate. Professional fighters had significantly more injuries than amateur fighters, resulting in three times higher injury rate. The most common body region injured was the head/neck/face (38.2%), followed by the lower extremities (30.4%), upper extremities (22.7%), torso (8.2%), and groin (0.5%). Injuries to the nose (6.3%), shoulder (6.3%), and toe (6.3%) were the most common. The most common type of injury was contusions (29.4%), followed by strains (16.2%), sprains (14.9%), and abrasions (10.1%). Conclusion Injury prevention efforts should consider the prevalence and distribution of injuries and focus on reducing or preventing injuries to the head/neck/face in MMA related activities. Preventative measures should focus on improving protective equipment during training, and possible competition rule modifications to further minimize participant injury. PMID:21509103

Poly(vinyl acetate-Based Block Copolymer/Clay Nanocomposites Prepared by In Situ Atom Transfer Radical Polymerization

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M.A. Semsarzadeh

2009-12-01

Full Text Available Atom transfer radical polymerization of styrene (St and methyl methacrylate (MMA was performed at 90oC in the absence and presence of nanoclay (Cloisite 30B. Trichloromethyl-terminated poly(vinyl acetate telomerand CuCl/ PMDETA were used as a macroinitiator and catalyst system, respectively. The experimental results showed that the atom transfer radical polymerization of St and MMA in the absence or presence of nanoclay proceeds via a controlled/living mode. It was observed that nanoclay significantly enhances the homopolymerization rate of MMA, which was attributed to the activated conjugated C=C bond of MMA monomer via interaction between the carbonyl group of MMA monomer and the hydroxyl moiety (Al-O-H of nanoclay as well as the effect of nanoclay on the dynamic equilibrium between the active (macro radicals and dormant species.Homopolymerization rate of St (a non-coordinative monomer with nanoclay decreased slightly in the presence of nanoclay. This could be explained by insertion of a portion of macroinitiator into the clay galleries, where no sufficient St monomer exists due to the low compatibility or interaction of St monomer with nanoclay to react with the macroinitiator. The results obtained from XRD, TEM and TGA analyses were fully in agreement with the kinetic data. Structure of the poly(vinyl acetate-bpolystyrene nanocomposite was found to be a combination of stacking layers and exfoliated structures while poly(vinyl acetate-b-poly(methyl methacryale nanocomposite had an exfoliated structure. This difference in the structure of nanocomposites was attributed to the different capability of the monomers (styrene and methyl methacrylate to react with the hydroxyl moiety (Al-O-H of nanoclay.

Cardiovascular effects in rats after intratracheal instillation of metal welding particles.

Science.gov (United States)

Zheng, Wen; Antonini, James M; Lin, Yen-Chang; Roberts, Jenny R; Kashon, Michael L; Castranova, Vincent; Kan, Hong

2015-01-01

Studies have indicated that pulmonary exposure to welding fumes can induce a series of adverse effects in the respiratory system, including infection, bronchitis, siderosis and decreased pulmonary function. Recent clinical and epidemiological studies have found that pulmonary exposure to welding fumes is also associated with a higher incidence of cardiovascular events. However, there is insufficient evidence to confirm a direct effect of welding fumes on the cardiovascular system. The present study investigated the effects of pulmonary exposure to welding fumes on the heart and the vascular system in rats. Two chemically distinct welding fumes generated from manual metal arc-hard surfacing (MMA-HS) and gas metal arc-mild steel (GMA-MS) welding were tested. Three groups of rats were instilled intratracheally with MMA-HS (2 mg/rat), GMA-MS (2 mg/rat) or saline as control once a week for seven weeks. On days 1 and 7 after the last treatment, basal cardiovascular function and the cardiovascular response to increasing doses of adrenoreceptor agonists were assessed. MMA-HS treatment reduced the basal levels of left ventricle end-systolic pressure and dP/dt(max) at 1 day post-treatment, and decreased dP/dt(min) in response to isoproterenol (ISO) at 7 days post-treatment. Unlike MMA-HS, GMA-MS only affected left ventricular end-diastolic pressure in response to ISO at 7 days post-treatment. Treatment with MMA-HS or GMA-MS did not alter heart rate and blood pressure. Our findings suggest that exposure to different welding fumes can induce different adverse effects on the cardiovascular system, and that cardiac contractility may be a sensitive indicator of cardiovascular dysfunction.

Povidone-Iodine-Based Polymeric Nanoparticles for Antibacterial Applications.

Science.gov (United States)

Gao, Tianyi; Fan, Hongbo; Wang, Xinjie; Gao, Yangyang; Liu, Wenxin; Chen, Wanjun; Dong, Alideertu; Wang, Yan-Jie

2017-08-09

As microbial contamination is becoming more and more serious, antibacterial agents play an important role in preventing and removing bacterial pathogens from microbial pollution in our daily life. To solve the issues with water solubility and antibacterial stability of PVP-I 2 (povidone-iodine) as a strong antibacterial agent, we successfully obtain hydrophobic povidone-iodine nanoparticles (povidone-iodine NPs) by a two-step method related to the advantage of nanotechnology. First, the synthesis of poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate) nanoparticles, i.e., P(NVP-MMA) NPs, was controlled by tuning a feed ratio of NVP to MMA. Then, the products P(NVP-MMA) NPs were allowed to undergo a complexation reaction with iodine, resulting in the formation of a water-insoluble antibacterial material, povidone-iodine NPs. It is found that the feed ratio of NVP to MMA has an active effect on morphology, chemical composition, molecular weight, and hydrophilic-hydrophobic properties of the P(NVP-MMA) copolymer after some technologies, such as SEM, DLS, elemental analysis, 1 H NMR, GPC, and the contact angle test, were used in the characterizations. The antibacterial property of povidone-iodine NPs was investigated by using Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa) as model bacteria with the colony count method. Interestingly, three products, such as glue, ink, and dye, after the incorporation of povidone-iodine NPs, show significant antibacterial properties. It is believed that, with the advantage of nanoscale morphology, the final povidone-iodine NPs should have great potential for utilization in various fields where antifouling and antibacterial properties are highly required.

Effect of modified graphene and microwave irradiation on the mechanical and thermal properties of poly(styrene-co-methyl methacrylate)/graphene nanocomposites

KAUST Repository

Zubair, Mukarram

2014-08-04

The effect of modified graphene (MG) and microwave irradiation on the interaction between graphene (G) and poly(styrene-co-methyl meth acrylate) [P(S-co-MMA)] polymer matrix has been studied in this article. Modification of graphene was performed using nitric acid. P(S-co-MMA) polymer was blended via melt blending with pristine and MG. The resultant nanocomposites were irradiated under microwave at three different time intervals (5, 10, and 20 min). Compared to pristine graphene, MG showed improved interaction with P(S-co-MMA) polymer (P) after melt mixing and microwave irradiation. The mechanism of improved dispersion and interaction of modified graphene with P(S-co-MMA) polymer matrix during melt mixing and microwave irradiation is due to the presence of oxygen functionalities on the surface of MG as confirmed from Fourier transform infrared spectroscopy. The formation of defects on modified graphene and free radicals on P(S-co-MMA) polymer chains after irradiation as explained by Raman spectroscopy and X-Ray diffraction studies. The nanocomposites with 0.1 wt% G and MG have shown a 26% and 38% increase in storage modulus. After irradiation (10 min), the storage modulus further improved to 11.9% and 27.6% of nanocomposites. The glass transition temperature of nanocomposites also improved considerably after melt mixing and microwave irradiation (but only for polymer MG nanocomposite). However, at higher irradiation time (20 min), degradation of polymer nanocomposites occurred. State of creation of crosslink network after 10 min of irradiation and degradation after 20 min of irradiation of nanocomposites was confirmed from SEM studies. Copyright © 2014 John Wiley & Sons, Ltd.

Amines in boreal forest air at SMEAR II station in Finland

Science.gov (United States)

Hemmilä, Marja; Hellén, Heidi; Virkkula, Aki; Makkonen, Ulla; Praplan, Arnaud P.; Kontkanen, Jenni; Ahonen, Lauri; Kulmala, Markku; Hakola, Hannele

2018-05-01

We measured amines in boreal forest air in Finland both in gas and particle phases with 1 h time resolution using an online ion chromatograph (instrument for Measuring AeRosols and Gases in Ambient Air - MARGA) connected to an electrospray ionization quadrupole mass spectrometer (MS). The developed MARGA-MS method was able to separate and detect seven different amines: monomethylamine (MMA), dimethylamine (DMA), trimethylamine (TMA), ethylamine (EA), diethylamine (DEA), propylamine (PA), and butylamine (BA). The detection limits of the method for amines were low (0.2-3.1 ng m-3), the accuracy of IC-MS analysis was 11-37 %, and the precision 10-15 %. The proper measurements in the boreal forest covered about 8 weeks between March and December 2015. The amines were found to be an inhomogeneous group of compounds, showing different seasonal and diurnal variability. Total MMA (MMA(tot)) peaked together with the sum of ammonia and ammonium ions already in March. In March, monthly means for MMA were NH4+ these were 52 ± 16 and 425 ± 371 ng m-3, respectively. Monthly medians in March for MMA(tot), NH3, and NH4+ were 90 %, gas-phase DMA correlated well with 1.1-2 nm particle number concentration (R2 = 0.63) suggesting that it participates in atmospheric clustering. EA concentrations were low all the time. Its July means were < 0.36 and 0.4 ± 0.4 ng m-3 in gas and aerosol phases, respectively, but individual concentration data correlated well with monoterpene concentrations in July. Monthly means of PA and BA were below detection limits at all times.

Remediation of organic and inorganic arsenic contaminated groundwater using a nanocrystalline TiO{sub 2}-based adsorbent

Energy Technology Data Exchange (ETDEWEB)

Jing Chuanyong, E-mail: cyjing@rcees.ac.c [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Meng Xiaoguang; Calvache, Edwin [Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Jiang Guibin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)

2009-08-15

A nanocrystalline TiO{sub 2}-based adsorbent was evaluated for the simultaneous removal of As(V), As(III), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in contaminated groundwater. Batch experimental results show that As adsorption followed pseudo-second order rate kinetics. The competitive adsorption was described with the charge distribution multi-site surface complexation model (CD-MUSIC). The groundwater containing an average of 329 mug L{sup -1} As(III), 246 mug L{sup -1} As(V), 151 mug L{sup -1} MMA, and 202 mug L{sup -1} DMA was continuously passed through a TiO{sub 2} filter at an empty bed contact time of 6 min for 4 months. Approximately 11 000, 14 000, and 9900 bed volumes of water had been treated before the As(III), As(V), and MMA concentration in the effluent increased to 10 mug L{sup -1}. However, very little DMA was removed. The EXAFS results demonstrate the existence of a bidentate binuclear As(V) surface complex on spent adsorbent, indicating the oxidation of adsorbed As(III). - A nanocrystalline TiO{sub 2}-based adsorbent could be used for the simultaneous removal of As(V), As(III), MMA, and DMA in contaminated groundwater.

Mechanism of alternating copolymerization of methyl methacrylate with styrene in the presence of diethylaluminum chloride

International Nuclear Information System (INIS)

Zubov, V.P.; Lachinov, M.B.; Ignatova, E.V.; Georgiev, G.S.; Golubev, V.B.; Kabanov, V.A.

1982-01-01

A kinetic study of the propagation mechanism of the alternating copolymerization of styrene (St) with methyl methacrylate (MMA) in the presence of a complexing agent (diethylaluminum chloride, DEAC) in bulk and in tetrachloroethylene solutions at a molar ratio DEAC/MMA = 0.5 has been carried out. It has been shown that the copolymerization is a chain radical process characterized by a short active-center lifetime, bimolecular termination, and high rate of chain transfer to the complexed MMA. A kinetic scheme has been proposed for the propagation mechanism of alternating copolymerization in the presence of a complexing agent not requiring independent measurements of the equilibrium constant of complexation. It has been found that spontaneous and uv-initiated copolymerizations in the system have different mechanisms of initiation and a common mechanism of propagation. The propagation proceeds by addition of single monomers as well as donor-acceptor complexes of the comonomers to the propagation radicals, with the first mechanism being predominant. Inclusion of the monomers in the complex leads to an increase of the St reactivity and to a decrease of the MMA reactivity in propagation to the corresponding macroradicals in comparison with the reactivity of the free monomers. A number of kinetic and statistical parameters of the propagation reaction have been calculated

A review of time-motion analysis and combat development in mixed martial arts matches at regional level tournaments.

Science.gov (United States)

del Vecchio, Fabrício Boscolo; Hirata, Sérgio Masashi; Franchini, Emerson

2011-04-01

Mixed martial arts (MMA) have become a fast-growing worldwide expansion of martial arts competition, requiring high level of skill, physical conditioning, and strategy, and involving a synthesis of combat while standing or on the ground. This study quantified the effort-pause ratio (EP), and classified effort segments of stand-up or groundwork development to identify the number of actions performed per round in MMA matches. 52 MMA athletes participated in the study (M age = 24 yr., SD = 5; average experience in MMA = 5 yr., SD = 3). A one-way analysis of variance with repeated measurements was conducted to compare the type of action across the rounds. A chi-squared test was applied across the percentages to compare proportions of different events. Only one significant difference (p < .05) was observed among rounds: time in groundwork of low intensity was longer in the second compared to the third round. When the interval between rounds was not considered, the EP ratio (between high-intensity effort to low-intensity effort plus pauses) was 1:2 to 1:4. This ratio is between ratios typical for judo, wrestling, karate, and taekwondo and reflects the combination of ground and standup techniques. Most of the matches ended in the third round, involving high-intensity actions, predominantly executed during groundwork combat.

Injuries Sustained by the Mixed Martial Arts Athlete.

Science.gov (United States)

Jensen, Andrew R; Maciel, Robert C; Petrigliano, Frank A; Rodriguez, John P; Brooks, Adam G

2016-08-16

Mixed martial arts (MMA) is rapidly growing in popularity in the United States and abroad. This combat sport joins athletes from a wide variety of martial art disciplines, each with characteristic and distinguishing injury profiles, together in competition. Because of increasing participation by professionals and amateurs alike, injuries sustained by MMA athletes have been on the rise. A review of relevant publications using the search term mixed martial arts and each of its component combat sports (eg, Muay Thai, Brazilian jiu-jitsu) from 1980 through 2015 was completed using PubMed and Google Scholar. Clinical review. Level 5. The majority of studies on MMA injuries evaluate those sustained during competition, which range in incidence from 22.9 to 28.6 per 100 fight-participations. Striking-predominant disciplines such as boxing, karate, and Muay Thai have high rates of head and facial injuries, whereas submission-predominant disciplines such as Brazilian jiu-jitsu, judo, and wrestling have high rates of joint injuries. Numerous studies have evaluated injuries in athletes who participate in MMA and its component disciplines during competition but much remains to be discovered about injuries sustained during training and in specific patient populations such as adolescents and women. © 2016 The Author(s).

A Potential Synergy between Incomplete Arsenic Methylation Capacity and Demographic Characteristics on the Risk of Hypertension: Findings from a Cross-Sectional Study in an Arsenic-Endemic Area of Inner Mongolia, China

Directory of Open Access Journals (Sweden)

Yongfang Li

2015-03-01

Full Text Available Inefficient arsenic methylation capacity has been associated with various health hazards induced by arsenic. In this study, we aimed to explore the interaction effect of lower arsenic methylation capacity with demographic characteristics on hypertension risk. A total of 512 adult participants (126 hypertension subjects and 386 non-hypertension subjects residing in an arsenic-endemic area in Inner Mongolia, China were included. Urinary levels of inorganic arsenic (iAs, monomethylarsonic acid (MMA, and dimethylarsinic acid (DMA were measured for all subjects. The percentage of urinary arsenic metabolites (iAs%, MMA%, and DMA%, primary methylation index (PMI and secondary methylation index (SMI were calculated to assess arsenic methylation capacity of individuals. Results showed that participants carrying a lower methylation capacity, which is characterized by lower DMA% and SMI, have a higher risk of hypertension compared to their corresponding references after adjusting for multiple confounders. A potential synergy between poor arsenic methylation capacity (higher MMA%, lower DMA% and SMI and older age or higher BMI were detected. The joint effects of higher MMA% and lower SMI with cigarette smoking also suggest some evidence of synergism. The findings of present study indicated that inefficient arsenic methylation capacity was associated with hypertension and the effect might be enhanced by certain demographic factors.

Study on grafting of different types of acrylic monomers onto natural rubber by γ-rays

International Nuclear Information System (INIS)

Dafader, N.C.; Haque, M.E.; Akhtar, F.; Ahmad, M.U.

2006-01-01

A comparative study of various acrylic monomers for grafting onto natural rubber was done. The stability of natural rubber latex (NRL) against coagulum with monomer, mechanical properties of grafted rubbers and percent of grafting were investigated. The NRL with monomers, methylacrylate (MA), ethylacrylate (EA) and n-butylacrylate (n-BA), is unstable but it is stable with methyl methacrylate (MMA), n-butyl methacrylate (BMA) and cyclohexyl methacrylate (CHMA). The mechanical properties and degree of grafting attained a maximum at a total radiation dose of 4 kGy. The values of tensile properties of MMA and CHMA grafted rubbers are almost similar, and higher than those of BMA grafted rubbers. On the other hand, the degree of grafting for CHMA is higher than those of MMA and BMA grafted rubbers. The infrared (IR) spectra of monomer grafted natural rubber were also studied

Thermal behavior of novel hybrid inorganic-organic phosphazene polymers

NARCIS (Netherlands)

Bosscher, G; Wieringa, RH; Jekel, AP; vandeGrampel, JC

The thermal behavior of the following systems have been investigated by TGA and XPS: the homopolymer of N3P3Cl4(CH3)(CH2C6H4CH=CH2) (1), copolymers of 1 with MMA and styrene, and copolymers of N3P3Cl4(i-C3H7) {C[OC(O)CH3]=CH2} (2) with MMA and styrene. Upon heating under TGA conditions the highest

Injuries Sustained by the Mixed Martial Arts Athlete

OpenAIRE

Jensen, Andrew R.; Maciel, Robert C.; Petrigliano, Frank A.; Rodriguez, John P.; Brooks, Adam G.

2016-01-01

Context: Mixed martial arts (MMA) is rapidly growing in popularity in the United States and abroad. This combat sport joins athletes from a wide variety of martial art disciplines, each with characteristic and distinguishing injury profiles, together in competition. Because of increasing participation by professionals and amateurs alike, injuries sustained by MMA athletes have been on the rise. Evidence Acquisition: A review of relevant publications using the search term mixed martial arts an...

ESR study of the radiolysis of cellobiose, cellulose-containing materials, and their mixtures with methyl methacrylate

International Nuclear Information System (INIS)

Kozlova, E.Y.; Shostenko, A.G.; Ermolaev, S.V.

1995-01-01

The ESR spectra of γ-irradiated cellobiose, paper waste, and cellulose extracted from paper waste and waste pulp sludge were analyzed. The kinetics of formation and decay of cellobiose radicals were investigated, and the radiation-chemical yields of the radicals formed in cellulose-containing materials were calculated. The ESR spectra of cellobiose irradiated in the presence of methyl methacrylate (MMA) were obtained. A probable mechanism of MMA grafting onto cellulose-containing matrices is considered

The Evaluation of Relationship between Spirometric Disorders and Methyl methacrylate in Dental Laboratories Personnel

OpenAIRE

E. Nadi; M.J. Asari; A. Zamanian

2010-01-01

Introduction & Objective: Methyl methacrylate (MMA), as a monomer of acrylic resin that has a wide variety of usages in denture fabrication, is considered as an air pollution indicator in the laboratories. Occupational exposure to these compound vapors can cause respiratory hypersensitivity, occupational asthma, eye and skin irritation and Allergic Contact Dermatitis (ACD). Therefore control of MMA exposure may promote the personnel’s health. The aim of this study was to determine the relati...

Magnetic Resonance Imaging Findings of Adult-Onset Glutaric Aciduria Type

Energy Technology Data Exchange (ETDEWEB)

Sonmez, G.; Mutlu, H.; Ozturk, E.; Sildiroglu, H.O.; Keskin, A.T.; Basekim, C.C.; Kizilkaya, E. [Dept. of Radiology, GATA Haydarpasa Teaching Hospital, Istanbul (Turkey)

2007-07-15

Glutaric aciduria or glutaric acidemia type I, an autosomal recessive disease, usually presents with an acute encephalopathic crisis in young children. We report the magnetic resonance (MR) and proton MR spectroscopy (MRS) imaging findings of a previously healthy 20-year-old man who presented with recurrent headaches. Organic acids from the patient's urine contained large amounts of adipate, glutarate, and 3-hydroxyglutarate consistent with glutaric aciduria type I.

Magnetic Resonance Imaging Findings of Adult-Onset Glutaric Aciduria Type

International Nuclear Information System (INIS)

Sonmez, G.; Mutlu, H.; Ozturk, E.; Sildiroglu, H.O.; Keskin, A.T.; Basekim, C.C.; Kizilkaya, E.

2007-01-01

Glutaric aciduria or glutaric acidemia type I, an autosomal recessive disease, usually presents with an acute encephalopathic crisis in young children. We report the magnetic resonance (MR) and proton MR spectroscopy (MRS) imaging findings of a previously healthy 20-year-old man who presented with recurrent headaches. Organic acids from the patient's urine contained large amounts of adipate, glutarate, and 3-hydroxyglutarate consistent with glutaric aciduria type I

Magnetic Resonance Imaging Findings of Adult-Onset Glutaric Aciduria Type I

Energy Technology Data Exchange (ETDEWEB)

Sonmez, G.; Mutlu, H.; Ozturk, E.; Sildiroglu, H.O.; Keskin, A.T.; Basekim, C.C.; Kizilkaya, E. [Dept. of Radiology, GATA Haydarpasa Teaching Hospital, Istanbul (Turkey)

2007-07-15

Glutaric aciduria or glutaric acidemia type I, an autosomal recessive disease, usually presents with an acute encephalopathic crisis in young children. We report the magnetic resonance (MR) and proton MR spectroscopy (MRS) imaging findings of a previously healthy 20-year-old man who presented with recurrent headaches. Organic acids from the patient's urine contained large amounts of adipate, glutarate, and 3-hydroxyglutarate consistent with glutaric aciduria type I.

Molecular characterisation of a recombinant bovine glycine N-acyltransferase / Christoffel Petrus Stephanus Badenhorst

OpenAIRE

Badenhorst, Christoffel Petrus Stephanus

2010-01-01

Conjugation of glycine to organic acids is an important detoxification mechanism. Metabolites of aspirin and industrial solvents, benzoic acid found in plant material and many endogenous metabolites are detoxified by conjugation to glycine. The enzyme responsible for glycine conjugation, glycine N-acyltransferase (GL YAT), is investigated in this study. The enzyme is also important for the management of organic acidemias which are inherited metabolic diseases. However, not all ...

Walter Reed Army Medical Center, Washington, D. C. - Annual Progress Report FY-89. Volume 1

Science.gov (United States)

1990-01-02

Enemas Cause Hyperphosphatemia and Acidemia in Patients with Ulcerative Colitis After Routine5 Colonic Cleansing." 4. LCDR Michael S. Opsahl, MC...Cholestyramine Treatment of 101 Thyrotoxicosis (3/88) 1303-88 Burman, Kenneth COL MC. The Clinical Application of In Situ 102 Hybridization to Detect Viral...Absorption of Commercial 144 (Oral) Calcium Carbonate Supplements (10/87) 1398-87 Solomon, Barbara DNSc. The Management of Hyperthyroidism Due 145 to

Effects of monomethylarsonic and monomethylarsonous acid on evoked synaptic potentials in hippocampal slices of adult and young rats

International Nuclear Information System (INIS)

Krueger, Katharina; Straub, Heidrun; Hirner, Alfred V.; Hippler, Joerg; Binding, Norbert; Musshoff, Ulrich

2009-01-01

Arsenite and its metabolites, dimethylarsinic or dimethylarsinous acid, have previously been shown to disturb synaptic transmission in hippocampal slices of rats (Krueger, K., Gruner, J., Madeja, M., Hartmann, L.M., Hirner, A.V., Binding, N., Muβhoff, U., 2006a. Blockade and enhancement of glutamate receptor responses in Xenopus oocytes by methylated arsenicals. Arch. Toxicol. 80, 492-501, Krueger, K., Straub, H., Binding, N., Muβhoff, U., 2006b. Effects of arsenite on long-term potentiation in hippocampal slices from adult and young rats. Toxicol. Lett. 165, 167-173, Krueger, K., Repges, H., Hippler, J., Hartmann, L.M., Hirner, A.V., Straub, H., Binding, N., Muβhoff, U., 2007. Effects of dimethylarsinic and dimethylarsinous acid on evoked synaptic potentials in hippocampal slices of young and adult rats. Toxicol. Appl. Pharmacol. 225, 40-46). The present experiments investigate, whether the important arsenic metabolites monomethylarsonic acid (MMA V ) and monomethylarsonous acid (MMA III ) also influence the synaptic functions of the hippocampus. In hippocampal slices of young (14-21 days-old) and adult (2-4 months-old) rats, evoked synaptic field potentials from the Schaffer collateral-CA1 synapse were measured under control conditions and during and after 30 and 60 min of application of the arsenic compounds. MMA V had no effect on the synapse functions neither in slices of adult nor in those from young rats. However, MMA III strongly influenced the synaptic transmission: it totally depressed the amplitudes of fEPSPs at concentrations of 50 μmol/l (adult rats) and 25 μmol/l (young rats) and LTP amplitudes at concentrations of 25 μmol/l (adult rats) and 10 μmol/l (young rats), respectively. In contrast, application of 1 μmol/l MMA III led to an enhancement of the LTP amplitude in young rats, which is interpretable by an enhancing effect on NMDA receptors and a lack of the blocking effect on AMPA receptors at this concentration (Krueger, K., Gruner, J

Identification of an S-adenosylmethionine (SAM) dependent arsenic methyltransferase in Danio rerio

Energy Technology Data Exchange (ETDEWEB)

Hamdi, Mohamad [Department of Biological Sciences, Oakland University, Rochester, MI 48309 (United States); Yoshinaga, Masafumi; Packianathan, Charles; Qin, Jie [Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, FL33199 (United States); Hallauer, Janell; McDermott, Joseph R. [Department of Biological Sciences, Oakland University, Rochester, MI 48309 (United States); Yang, Hung-Chi [Department of Medical Biotechnology and Laboratory Sciences, Chang-Gung University, Tao-Yuan, Kwei-San 333, Taiwan (China); Tsai, Kan-Jen [School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Liu, Zijuan, E-mail: liu2345@oakland.edu [Department of Biological Sciences, Oakland University, Rochester, MI 48309 (United States)

2012-07-15

Arsenic methylation is an important cellular metabolic process that modulates arsenic toxicity and carcinogenicity. Biomethylation of arsenic produces a series of mono-, di- and tri-methylated arsenic metabolites that can be detected in tissues and excretions. Here we report that zebrafish exposed to arsenite (As{sup III}) produces organic arsenicals, including MMA{sup III}, MMA{sup V} and DMA{sup V} with characteristic tissue ratios, demonstrating that an arsenic methylation pathway exists in zebrafish. In mammals, cellular inorganic arsenic is methylated by a SAM-dependent arsenic methyltransferase, AS3MT. A zebrafish arsenic methyltransferase homolog, As3mt, was identified by sequence alignment. Western blotting analysis showed that As3mt was universally expressed in zebrafish tissues. Prominent expression in liver and intestine correlated with methylated arsenic metabolites detected in those tissues. As3mt was expressed in and purified from Escherichia coli for in vitro functional studies. Our results demonstrated that As3mt methylated As{sup III} to DMA{sup V} as an end product and produced MMA{sup III} and MMA{sup V} as intermediates. The activity of As3mt was inhibited by elevated concentrations of the substrate As{sup III} as well as the metalloid selenite, which is a well-known antagonistic micronutrient of arsenic toxicity. The activity As3mt was abolished by substitution of either Cys160 or Cys210, which corresponds to conserved cysteine residues in AS3MT homologs, suggesting that they are involved in catalysis. Expression in zebrafish of an enzyme that has a similar function to human and rodent orthologs in catalyzing intracellular arsenic biomethylation validates the applicability of zebrafish as a valuable vertebrate model for understanding arsenic-associated diseases in humans. -- Highlights: ► Zebrafish methylated As{sup III} to MMA{sup III}, MMA{sup V} and DMA{sup V}. ► A zebrafish arsenic methyltransferase (As3mt) was purified in E. coli. �

Synthesis and characterization of poly(styrene-co-methyl methacrylate)

International Nuclear Information System (INIS)

Augustinho, Tiago R.; Abarca, Silvia A.C.; Machado, Ricardo A.F.

2011-01-01

Polystyrene (PS) is nowadays commonly used due its advantages over competitors. PS presents a lower cost when compared with Acrylonitrile Butadiene Styrene (ABS) and with Polyethylene Tere-phthalate (PET), and can be easier processed than polypropylene (PP). At expandable form (EPS), can be used as projective equipment, thermal insulation, floating boards, refrigerators, isothermal, and low cost applications such as packaging and disposable material. Searching for more resistant materials and with a low cost, researches with copolymers materials are being developed. In this study, copolymerization reactions were carried out by suspension polymerization using monomers styrene and methyl methacrylate (MMA) with styrene. Styrene was in the highest percentage in relation to the MMA. The MMA was selected because is a monomer that presents a higher resistance than PS. The copolymerization was confirmed by performing infrared spectroscopy (IR), nuclear magnetic resonance of hydrogen (RMN 1 H), differential scanning calorimetry (DSC) and thermogravimetry (TGA). (author)

Formation of compositional gradient profiles by using shear-induced polymer migration phenomenon under Couette flow field

Energy Technology Data Exchange (ETDEWEB)

Im, Sang Hyuk; Lee, Su Jin [Kyung Hee University, Yongin (Korea, Republic of); Suh, Duck Jong; Park, O Ok [Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of); Kwon, Moo Hyun [Woosuk University, Wanju (Korea, Republic of)

2015-07-15

We investigated whether a graded-index profile, specified by the polymer compositional gradient, could be formed using shear-induced polymer migration phenomenon in a polymer solution. For the presented model system, we generated a shear flow by rotating a glass rod at the center of a polystyrene/methylmethacrylate (PS/MMA) solution and measured the degree of polymer migration by the shear flow field by examining the concentration of polymer solution along the radial direction from the rotating axis to the periphery. Through model experiments, we formed a compositional gradient and controlled its profile in the solution by varying the concentration of polymer solution, molecular weight of polymer, and shear rate. Finally, we solidified the gradient profiles by the polymerization of the PS/MMA solution and confirmed that the gradient profiles were maintained with a compositional gradient twice larger than the mother PS/MMA solution.

Ultra-Thin Multi-Band Polarization-Insensitive Microwave Metamaterial Absorber Based on Multiple-Order Responses Using a Single Resonator Structure

Directory of Open Access Journals (Sweden)

Yong Zhi Cheng

2017-10-01

Full Text Available We design an ultra-thin multi-band polarization-insensitive metamaterial absorber (MMA using a single circular sector resonator (CSR structure in the microwave region. Simulated results show that the proposed MMA has three distinctive absorption peaks at 3.35 GHz, 8.65 GHz, and 12.44 GHz, with absorbance of 98.8%, 99.7%, and 98.3%, respectively, which agree well with an experiment. Simulated surface current distributions of the unit-cell structure reveal that the triple-band absorption mainly originates from multiple-harmonic magnetic resonance. The proposed triple-band MMA can remain at a high absorption level for all polarization of both transverse-electric (TE and transverse-magnetic (TM modes under normal incidence. Moreover, by further optimizing the geometric parameters of the CSRs, four-band and five-band MMAs can also be obtained. Thus, our design will have potential application in detection, sensing, and stealth technology.

Chemical resistance of core-shell particles (PS/PMMA) polymerized by seeded suspension

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Luiz Fernando Belchior; Machado, Ricardo Antonio Francisco, E-mail: ricardo.machado@ufsc.br [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Departamento de Engenharia de Materiais; Gonçalves, Odinei Hess [Universidade Técnológica Federal do Paraná(UTFPR), Campo Mourão, PR (Brazil); Marangoni, Cintia [Universidade Federal de Santa Catarina (UFSC), Blumenau, SC (Brazil); Motz, Günter [Lehrstuhl Keramische Werkstoffe, Universität Bayreuth (Germany)

2017-07-01

Core-shell particles were produced on seeded suspension polymerization by using polystyrene (PS) as polymer core, or seed, and methyl methacrylate (MMA) as the shell forming monomer. Two synthesis routes were evaluated by varying the PS seed conversion before MMA addition. The main purpose of this work was to investigate the influence of synthesis routes on the morphology and chemical resistance of the resulting particles. {sup 1}H NMR spectroscopy showed that the use of PS seeds with lower conversion led to the formation of higher amount of poly(styrene-co-MMA). The copolymer acted as a compatibilizer, decreasing the interfacial energy between both homopolymers. As a consequence, a larger amount of reduced PMMA cluster were formed, as was revealed by TEM measurements. Samples in this system showed enhanced resistance to cyclohexane attack compared with pure PS, with a PS extraction of only 37% after 54 hours test. (author)

Chemical resistance of core-shell particles (PS/PMMA polymerized by seeded suspension

Directory of Open Access Journals (Sweden)

Luiz Fernando Belchior Ribeiro

2017-09-01

Full Text Available Abstract Core-shell particles were produced on seeded suspension polymerization by using polystyrene (PS as polymer core, or seed, and methyl methacrylate (MMA as the shell forming monomer. Two synthesis routes were evaluated by varying the PS seed conversion before MMA addition. The main purpose of this work was to investigate the influence of synthesis routes on the morphology and chemical resistance of the resulting particles. 1H NMR spectroscopy showed that the use of PS seeds with lower conversion led to the formation of higher amount of poly(styrene-co-MMA. The copolymer acted as a compatibilizer, decreasing the interfacial energy between both homopolymers. As a consequence, a larger amount of reduced PMMA cluster were formed, as was revealed by TEM measurements. Samples in this system showed enhanced resistance to cyclohexane attack compared with pure PS, with a PS extraction of only 37% after 54 hours test.

Acceleration measurements in JEM

International Nuclear Information System (INIS)

Ikeda, Toshitami; Murakami, Keiji

2000-01-01

Since summer in 1996, National Space Development Agency of Japan (NASDA) has continued a concept study for a microgravity measurement apparatus (MMA) to be installed in the Japanese Experiment Module (JEM). The concept study was finished in 1998, and then we have been proceeding for a basic design. For experiments conducted with some of NASDA payloads in JEM-PM (Pressurized Module), measuring detailed microgravity environment was required. In addition, experiments to be performed with payload equipment attached on the JEM-EF (Exposed Facility) are requiring for obtaining the microgravity measurement data. Thus, we are adding some modification to the concept design of MMA in order to make the common hardware available for measurement of both environment in the JEM-PM and that of the JEM-EF. In this paper, the current development status of Japanese payloads and the modified concept of the MMA are introduced

A silicone rubber based composites using n-octadecane/poly (styrene-methyl methacrylate microcapsules as energy storage particle

Directory of Open Access Journals (Sweden)

W.L. Wu

Full Text Available A phase-change energy-storage material, silicone rubber (SR coated n-octadecane/poly (styrene-methyl methacrylate (SR/OD/P(St-MMA microcapsule composites, was prepared by mixing SR and OD/P(St-MMA microcapsules. The microcapsule content and silicone rubber coated method were investigated. The morphology and thermal properties of the composites were characterized by scanning electron microscopy (SEM, thermogravimetric analysis (TG, differential scanning calorimetry (DSC and heat storage properties. The results showed that the thermal and mechanical properties of SR/OD/P(St-MMA composites were excellent when the microcapsules were coated with room temperature vulcanized silicone rubber (RTVSR, of which content was 2 phr (per hundred rubber. The enthalpy value of the composites was 67.6 J g−1 and the composites were found to have good energy storage function. Keywords: n-Octadecane, Silicone rubber, Microcapsule, Energy-storage, Composites

Generator scheduling under competitive environment using Memory Management Algorithm

Directory of Open Access Journals (Sweden)

A. Amudha

2013-09-01

Full Text Available This paper presents a new approach for Real-Time Application of Profit Based Unit Commitment using Memory Management Algorithm. The main objective of the restructured system is to maximize its own profit without the responsibility of satisfying the forecasted demand. The Profit Based Unit Commitment (PBUC is solved by Memory Management Algorithm (MMA in Real-Time Application. MMA approach is introduced in this paper considering power and reserve generation. The proposed method MMA uses Best Fit and Worst Fit allocation for generator scheduling in order to receive the maximum profit by considering the softer demand. Also, this method gives an idea regarding how much power and reserve should be sold in markets. The proposed approach has been tested on a power system with 2, 3, and 10 generating units. Simulation results of the proposed approach have been compared with the existing methods.

Urinary arsenic methylation capability and carotid atherosclerosis risk in subjects living in arsenicosis-hyperendemic areas in southwestern Taiwan

Energy Technology Data Exchange (ETDEWEB)

Huang, Y.-L. [Department of Public Health, School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Hsueh, Y.-M. [Department of Public Health, School of Medicine, Taipei Medical University, Taipei, Taiwan (China)], E-mail: ymhsueh@tmu.edu.tw; Huang, Y.-K. [Graduate Institute of Medical Sciences, School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Yip, P.-K. [Department of Neurology, College of Medicine, National Taiwan University, Taiwan (China); Yang, M.-H. [Department of Nuclear Science, National Tsing-Hua University, Hsinchu, Taiwan (China); Chen, C.-J. [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China); Graduate Institute of Epidemiology, College of Public Health, National Taiwan University Taipei, Taiwan (China)

2009-04-01

Long-term exposure to inorganic arsenic from artesian drinking well water is associated with carotid atherosclerosis in the Blackfoot Disease (BFD)-hyperendemic area in Taiwan. The current study examined the arsenic methylation capacity and its risk on carotid atherosclerosis. A total of 304 adults (158 men and 146 women) residing in the BFD-hyperendemic area were included. The extent of carotid atherosclerosis was assessed by duplex ultrasonography. Chronic arsenic exposure was estimated by an index of cumulative arsenic exposure (CAE) and the duration of artesian well water consumption. Urinary levels of inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)] were determined by high performance liquid chromatography linked on-line to a hydride generator and atomic absorption spectrometry (HPLC-HG-AAS). The percentage of arsenic species, primary methylation index [PMI = MMA(V) / (As(III) + As(V)] and secondary methylation index [SMI = DMA(V) / MMA(V)] were calculated and employed as indicators of arsenic methylation capacity. Results showed that women and younger subjects had a more efficient arsenic methylation capacity than did men and the elderly. Carotid atherosclerosis cases had a significantly greater percentage of MMA(V) [%MMA(V)] and a lower percentage of DMA [%DMA (V)] compared to controls. Subjects in the highest two tertiles of PMI with a median of CAE > 0 mg/L-year had an odds ratio (OR) and a 95% confidence interval (CI) of carotid atherosclerosis of 2.61 and 0.98-6.90 compared to those in the highest two tertiles of PMI with a CAE = 0 mg/L-year. We conclude that individuals with greater exposure to arsenic and lower capacity to methylate inorganic arsenic may be at a higher risk to carotid atherosclerosis.

Preparation of thermo-responsive graft copolymer by using a novel macro-RAFT agent and its application for drug delivery

International Nuclear Information System (INIS)

Song, Cunfeng; Yu, Shirong; Liu, Cheng; Deng, Yuanming; Xu, Yiting; Chen, Xiaoling; Dai, Lizong

2016-01-01

A methodology to prepare thermo-responsive graft copolymer by using a novel macro-RAFT agent was proposed. The macro-RAFT agent with pendant dithioester (ZC(S)SR) was facilely prepared via the combination of RAFT polymerization and esterification reaction. By means of ZC(S)SR-initiated RAFT polymerization, the thermo-responsive graft copolymer consisting of poly(methyl methacrylate-co-hydroxylethyl methacrylate) (P(MMA-co-HEMA)) backbone and hydrophilic poly(N-isopropylacrylamide) (PNIPAAm) side chains was constructed through the “grafting from” approach. The chemical compositions and molecular weight distributions of the synthesized polymers were respectively characterized by "1H nuclear magnetic resonance ("1H NMR) and gel permeation chromatography (GPC). Self-assembly behavior of the amphiphilic graft copolymers (P(MMA-co-HEMA)-g-PNIPAAm) was studied by transmission electron microscopy (TEM), dynamic light scattering (DLS) and spectrofluorimeter. The critical micelle concentration (CMC) value was 0.052 mg mL"−"1. These micelles have thermo-responsibility and a low critical solution temperature (LCST) of 33.5 °C. Further investigation indicated that the guest molecule release property of these micelles, which can be well described by a first-order kinetic model, was significantly affected by temperature. Besides, the micelles exhibited excellent biocompatibility and cellular uptake property. Hence, these micelles are considered to have potential application in controlled drug delivery. - Highlights: • A novel macro-RAFT agent with ZC(S)SR was used for preparing graft copolymer. • P(MMA-co-HEMA)-g-PNIPAAm was successful prepared via the “grafting from” approach. • Thermo-responsibility of the P(MMA-co-HEMA)-g-PNIPAAm micelles was investigated. • The drug release behavior of the P(MMA-co-HEMA)-g-PNIPAAm micelles was studied. • These micelles exhibited excellent biocompatibility and cellular uptake property.

Preparation of thermo-responsive graft copolymer by using a novel macro-RAFT agent and its application for drug delivery

Energy Technology Data Exchange (ETDEWEB)

Song, Cunfeng; Yu, Shirong [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Liu, Cheng; Deng, Yuanming; Xu, Yiting [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Fujian Provincial Key Laboratory of Fire Retardant Materials, Xiamen University, Xiamen 361005 (China); Chen, Xiaoling, E-mail: tinachen0628@163.com [Department of Endodontics, Xiamen Stomatology Hospital, Teaching Hospital of Fujian Medical University, Xiamen 361003 (China); Dai, Lizong, E-mail: lzdai@xmu.edu.cn [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Fujian Provincial Key Laboratory of Fire Retardant Materials, Xiamen University, Xiamen 361005 (China)

2016-05-01

A methodology to prepare thermo-responsive graft copolymer by using a novel macro-RAFT agent was proposed. The macro-RAFT agent with pendant dithioester (ZC(S)SR) was facilely prepared via the combination of RAFT polymerization and esterification reaction. By means of ZC(S)SR-initiated RAFT polymerization, the thermo-responsive graft copolymer consisting of poly(methyl methacrylate-co-hydroxylethyl methacrylate) (P(MMA-co-HEMA)) backbone and hydrophilic poly(N-isopropylacrylamide) (PNIPAAm) side chains was constructed through the “grafting from” approach. The chemical compositions and molecular weight distributions of the synthesized polymers were respectively characterized by {sup 1}H nuclear magnetic resonance ({sup 1}H NMR) and gel permeation chromatography (GPC). Self-assembly behavior of the amphiphilic graft copolymers (P(MMA-co-HEMA)-g-PNIPAAm) was studied by transmission electron microscopy (TEM), dynamic light scattering (DLS) and spectrofluorimeter. The critical micelle concentration (CMC) value was 0.052 mg mL{sup −1}. These micelles have thermo-responsibility and a low critical solution temperature (LCST) of 33.5 °C. Further investigation indicated that the guest molecule release property of these micelles, which can be well described by a first-order kinetic model, was significantly affected by temperature. Besides, the micelles exhibited excellent biocompatibility and cellular uptake property. Hence, these micelles are considered to have potential application in controlled drug delivery. - Highlights: • A novel macro-RAFT agent with ZC(S)SR was used for preparing graft copolymer. • P(MMA-co-HEMA)-g-PNIPAAm was successful prepared via the “grafting from” approach. • Thermo-responsibility of the P(MMA-co-HEMA)-g-PNIPAAm micelles was investigated. • The drug release behavior of the P(MMA-co-HEMA)-g-PNIPAAm micelles was studied. • These micelles exhibited excellent biocompatibility and cellular uptake property.

Evaluation of the molecular mechanisms associated with cytotoxicity and inflammation after pulmonary exposure to different metal-rich welding particles.

Science.gov (United States)

Shoeb, Mohammad; Kodali, Vamsi; Farris, Breanne; Bishop, Lindsey M; Meighan, Terence; Salmen, Rebecca; Eye, Tracy; Roberts, Jenny R; Zeidler-Erdely, Patti; Erdely, Aaron; Antonini, James M

2017-08-01

Welding generates a complex aerosol of incidental nanoparticles and cytotoxic metals, such as chromium (Cr), manganese (Mn), nickel (Ni), and iron (Fe). The goal was to use both in vivo and in vitro methodologies to determine the mechanisms by which different welding fumes may damage the lungs. Sprague-Dawley rats were treated by intratracheal instillation (ITI) with 2.0 mg of gas metal arc-mild steel (GMA-MS) or manual metal arc-stainless steel (MMA-SS) fumes or saline (vehicle control). At 1, 3, and 10 days, bronchoalveolar lavage (BAL) was performed to measure lung toxicity. To assess molecular mechanisms of cytotoxicity, RAW264.7 cells were exposed to both welding fumes for 24 h (0-100 μg/ml). Fume composition was different: MMA-SS (41% Fe, 29% Cr, 17% Mn, 3% Ni) versus GMA-MS (85% Fe, 14% Mn). BAL indicators of lung injury and inflammation were increased by MMA-SS at all time points and by GMA-MS at 3 and 10 days after exposure. RAW264.7 cells exposed to MMA-SS had elevated generation of reactive oxygen species (ROS), protein-HNE (P-HNE) adduct formation, activation of ERK1/2, and expression of cyclooxygenase-2 (COX-2) compared to GMA-MS and control. Increased generation of ROS due to MMA-SS exposure was confirmed by increased expression of Nrf2 and heme oxygenase-1 (HO-1). Results of in vitro studies provide evidence that stainless steel welding fume mediate inflammatory responses via activation of ROS/P-HNE/ERK1/2/Nrf2 signaling pathways. These findings were corroborated by elevated expression of COX-2, Nrf2, and HO-1 in homogenized lung tissue collected 1 day after in vivo exposure.

Urinary arsenic methylation capability and carotid atherosclerosis risk in subjects living in arsenicosis-hyperendemic areas in southwestern Taiwan

International Nuclear Information System (INIS)

Huang, Y.-L.; Hsueh, Y.-M.; Huang, Y.-K.; Yip, P.-K.; Yang, M.-H.; Chen, C.-J.

2009-01-01

Long-term exposure to inorganic arsenic from artesian drinking well water is associated with carotid atherosclerosis in the Blackfoot Disease (BFD)-hyperendemic area in Taiwan. The current study examined the arsenic methylation capacity and its risk on carotid atherosclerosis. A total of 304 adults (158 men and 146 women) residing in the BFD-hyperendemic area were included. The extent of carotid atherosclerosis was assessed by duplex ultrasonography. Chronic arsenic exposure was estimated by an index of cumulative arsenic exposure (CAE) and the duration of artesian well water consumption. Urinary levels of inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)] were determined by high performance liquid chromatography linked on-line to a hydride generator and atomic absorption spectrometry (HPLC-HG-AAS). The percentage of arsenic species, primary methylation index [PMI = MMA(V) / (As(III) + As(V)] and secondary methylation index [SMI = DMA(V) / MMA(V)] were calculated and employed as indicators of arsenic methylation capacity. Results showed that women and younger subjects had a more efficient arsenic methylation capacity than did men and the elderly. Carotid atherosclerosis cases had a significantly greater percentage of MMA(V) [%MMA(V)] and a lower percentage of DMA [%DMA (V)] compared to controls. Subjects in the highest two tertiles of PMI with a median of CAE > 0 mg/L-year had an odds ratio (OR) and a 95% confidence interval (CI) of carotid atherosclerosis of 2.61 and 0.98-6.90 compared to those in the highest two tertiles of PMI with a CAE = 0 mg/L-year. We conclude that individuals with greater exposure to arsenic and lower capacity to methylate inorganic arsenic may be at a higher risk to carotid atherosclerosis

Urinary arsenic concentrations and speciation in residents living in an area with naturally contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Fillol, Clemence, E-mail: c.fillol@invs.sante.fr [Universite Paris Descartes, Laboratoire Sante Publique et Environnement - EA 4064, Paris (France); Institut de veille sanitaire, Departement Sante environnement, Saint-Maurice (France); Dor, Frederic [Institut de veille sanitaire, Departement Sante environnement, Saint-Maurice (France); Labat, Laurence [CHRU de Lille, Laboratoire de Toxicologie et Genopathies, Lille (France); Boltz, Patricia [Centre antipoison et de toxicovigilance de Nancy (France); Le Bouard, Jerome [Direction Regionale des Affaires Sanitaires et Sociales, Meurthe-et-Moselle (France); Mantey, Karine [Cellule Interregionale d' epidemiologie de l' Est (France); Mannschott, Christian [Direction Departementale des Affaires Sanitaires et Sociales 54, Meurthe-et-Moselle (France); Puskarczyk, Emmanuel [Centre antipoison et de toxicovigilance de Nancy (France); Viller, Frederique [Cellule Interregionale d' epidemiologie de l' Est (France); Momas, Isabelle [Universite Paris Descartes, Laboratoire Sante Publique et Environnement - EA 4064, Paris (France); Seta, Nathalie [Universite Paris Descartes, Laboratoire Sante Publique et Environnement - EA 4064, Paris (France); AP-HP, Hopital Bichat, Biochimie, Paris (France)

2010-02-01

A cross sectional study was carried out to evaluate arsenic exposure of residents living in an area with a soil naturally rich in arsenic (As), through urinary measurements. During the summer of 2007, 322 people aged over 7 years and resident in the study area for at least 4 days prior to the investigation were recruited. The sum of urinary inorganic arsenic and metabolites (iAs + MMA + DMA) and speciation were determined by graphite furnace atomic absorption spectrometry and high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry, respectively. Geometric means levels of iAs + MMA + DMA were 3.6 {mu}g/L or 4.4 {mu}g/g creatinine. The percent of DMA, As(III) and MMA contribution to urinary arsenic concentrations was respectively 84.2%, 12% and 3.7%. We found significant associations between urinary arsenic concentrations and the consumption of seafood (p = 0.03), the consumption of wine (p = 0.03) and beer (p = 0.001), respectively 3 and 4 days before the investigation. When we focus on the various species, As(V) was rarely detected and DMA is the predominant metabolite composing the majority of measurable inorganic-related As in the urine. Considering the percent of DMA contribution to iAs + MMA + DMA urinary concentrations, almost half of the subjects had 100% of DMA contribution whatever the concentration of urinary As whereas the others had a lower DMA contribution, between 39 and 90%. Arsenic levels reported in this original study in France were between 2 and 4 times lower than in other studies dealing with iAs + MMA + DMA levels associated with soil arsenic exposure. Arsenic levels were similar to those observed in unexposed individuals in European countries, although 10% were above the French guideline values for the general population.

Effects of endogenous hydrogen peroxide and glutathione on the stability of arsenic metabolites in rat bile

International Nuclear Information System (INIS)

Kobayashi, Yayoi; Hirano, Seishiro

2008-01-01

Trivalent arsenicals such as arsenite (iAs III ), monomethylarsonous acid (MMA III ) and dimethylarsinous acid (DMA III ) are more toxic than analogous pentavalent compounds such as arsenate (iAs V ), monomethylarsonic acid (MMA V ) and dimethylarsinic acid (DMA V ). It has been reported that arsenic-glutathione (As-GSH) complexes such as arsenic triglutathione (ATG) and methylarsenic diglutathione (MADG) are major metabolites in rat bile following intravenous administration of iAs III . Recently, we have shown that both ATG and MADG are unstable and easily hydrolyzed to iAs III and MMA III , respectively, and that MMA III is oxidized to MMA V in bile. In the present study we report the effects of H 2 O 2 and GSH on the stability of As-GSH complexes in rat bile. Male SD rats were injected intravenously with saline or iAs III at a dose of 0.2 or 2.0 mg As/kg body weight, and bile fluid was collected on ice for 30 min. To estimate the stability of As-GSH complexes in bile, ATG or MADG was added to untreated, heat-treated, catalase-treated, or dialyzed bile, and then incubated at 37 deg. C for 10 min. Concentrations of biliary H 2 O 2 and GSH in the higher dose group were 12.6- and 4.5-times higher than the control value, respectively. Exogenously added trivalent arsenicals were oxidized to pentavalent arsenicals in the bile depending on the biliary concentration of H 2 O 2 . Both catalase and dialysis prevented oxidation of trivalent arsenicals to the corresponding pentavalent compounds. Exogenously added GSH stabilized As-GSH complexes in bile. These results suggest that H 2 O 2 converts trivalent arsenicals to less toxic pentavalent arsenicals, whereas GSH prevents hydrolysis of As-GSH complexes and the generation of unconjugated toxic trivalent arsenicals

Urinary arsenic concentrations and speciation in residents living in an area with naturally contaminated soils

International Nuclear Information System (INIS)

Fillol, Clemence; Dor, Frederic; Labat, Laurence; Boltz, Patricia; Le Bouard, Jerome; Mantey, Karine; Mannschott, Christian; Puskarczyk, Emmanuel; Viller, Frederique; Momas, Isabelle; Seta, Nathalie

2010-01-01

A cross sectional study was carried out to evaluate arsenic exposure of residents living in an area with a soil naturally rich in arsenic (As), through urinary measurements. During the summer of 2007, 322 people aged over 7 years and resident in the study area for at least 4 days prior to the investigation were recruited. The sum of urinary inorganic arsenic and metabolites (iAs + MMA + DMA) and speciation were determined by graphite furnace atomic absorption spectrometry and high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry, respectively. Geometric means levels of iAs + MMA + DMA were 3.6 μg/L or 4.4 μg/g creatinine. The percent of DMA, As(III) and MMA contribution to urinary arsenic concentrations was respectively 84.2%, 12% and 3.7%. We found significant associations between urinary arsenic concentrations and the consumption of seafood (p = 0.03), the consumption of wine (p = 0.03) and beer (p = 0.001), respectively 3 and 4 days before the investigation. When we focus on the various species, As(V) was rarely detected and DMA is the predominant metabolite composing the majority of measurable inorganic-related As in the urine. Considering the percent of DMA contribution to iAs + MMA + DMA urinary concentrations, almost half of the subjects had 100% of DMA contribution whatever the concentration of urinary As whereas the others had a lower DMA contribution, between 39 and 90%. Arsenic levels reported in this original study in France were between 2 and 4 times lower than in other studies dealing with iAs + MMA + DMA levels associated with soil arsenic exposure. Arsenic levels were similar to those observed in unexposed individuals in European countries, although 10% were above the French guideline values for the general population.

Recommendations for analysis of repeated-measures designs: testing and correcting for sphericity and use of manova and mixed model analysis.

Science.gov (United States)

Armstrong, Richard A

2017-09-01

A common experimental design in ophthalmic research is the repeated-measures design in which at least one variable is a within-subject factor. This design is vulnerable to lack of 'sphericity' which assumes that the variances of the differences among all possible pairs of within-subject means are equal. Traditionally, this design has been analysed using a repeated-measures analysis of variance (RM-anova) but increasingly more complex methods such as multivariate anova (manova) and mixed model analysis (MMA) are being used. This article surveys current practice in the analysis of designs incorporating different factors in research articles published in three optometric journals, namely Ophthalmic and Physiological Optics (OPO), Optometry and Vision Science (OVS), and Clinical and Experimental Optometry (CXO), and provides advice to authors regarding the analysis of repeated-measures designs. Of the total sample of articles, 66% used a repeated-measures design. Of those articles using a repeated-measures design, 59% and 8% analysed the data using RM-anova or manova respectively and 33% used MMA. The use of MMA relative to RM-anova has increased significantly since 2009/10. A further search using terms to select those papers testing and correcting for sphericity ('Mauchly's test', 'Greenhouse-Geisser', 'Huynh and Feld') identified 66 articles, 62% of which were published from 2012 to the present. If the design is balanced without missing data then manova should be used rather than RM-anova as it gives better protection against lack of sphericity. If the design is unbalanced or with missing data then MMA is the method of choice. However, MMA is a more complex analysis and can be difficult to set up and run, and care should be taken first, to define appropriate models to be tested and second, to ensure that sample sizes are adequate. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

An Abstraction Hierarchy based mobile PC display design in NPP maintenance considering the level of expertise

International Nuclear Information System (INIS)

Yim, Ho Bin; Kim, In; Seong, Poong Hyun

2011-01-01

Research highlights: → Six levels of Abstraction Hierarchy based information for maintenance were proposed. → Errors and workload with AH based information display were reduced for LL subjects. → Design concerns discovered can be applied to practical use of mobile maintenance aids. - Abstract: Recently, the importance of effective maintenance in nuclear power plants (NPPs) has been emphasized and research into effective maintenance by adopting mobile maintenance aids (MMAs) have been attempted. For improved and effective use of an MMA display design method based on the hierarchy is proposed and its design considerations are discussed in this study. Six levels of hierarchy are proposed in this paper to classify the maintenance information. By classifying and organizing maintenance information using the hierarchy, maintenance information can be used effectively by users with either high or low levels of expertise. When information classification has been finished, the information for MMA design is selected and designed. With the considerations of MMA design analysis and guidelines, a hierarchy-based MMA is designed for the maintenance tasks. An experiment is conducted using the hierarchy-based MMA in order to estimate the effectiveness of the proposed method for the maintenance tasks and to identify design considerations to enhance the proposed MMAs. The result indicated that a hierarchy-based manual was more effective than a conventional manual in terms of task completion time and number of errors. The workload for the hierarchy-based manual was estimated less than the conventional manual for subjects with low level of expertise. As the level of expertise increases, subjects tended to follow more abstract information while the number of navigations decreased. It is believed that when mobile devices become pervasive in NPP maintenance fields, the hierarchy model applied MMAs can be used as an effective maintenance supporting tool.

A comparative study on the properties of graphene oxide and activated carbon based sustainable wood starch composites.

Science.gov (United States)

Baishya, Prasanta; Maji, Tarun Kumar

2018-08-01

Activated carbon (AC) prepared from Jatropha curcas and graphene oxide (GO) were employed in the preparation of natural polymer based wood starch composites (WSC) through the solution blending technique using water as a solvent. In this study, methyl methacrylate (MMA) was grafted onto the starch polymer and this MMA grafted starch (MMA-g-starch) was cross-linked with the cheap soft wood flour using the citric acid as cross-linker and water as a solvent in the whole process. The prepared GO and AC were characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), thermogravimetric analysis (TGA) and Raman study. The interaction of GO and AC, with MMA-g-starch, citric acid and wood were studied by FTIR, XRD and SEM analysis. The GO and AC treated composites exhibited outstanding mechanical properties, thermal stability and fire resistance properties. The tensile strength of the composites increased by 178% and 200% with addition of 2 phr AC and GO respectively compared to untreated composites. A significant enhancement in water resistance properties of GO and AC treated composites was also attained. The study showed that the properties of the composites containing AC prepared from the seeds of Jatropha curcas was quite comparable with the composites reinforced with GO. Copyright © 2018 Elsevier B.V. All rights reserved.

Determinants and Consequences of Arsenic Metabolism Efficiency among 4,794 Individuals: Demographics, Lifestyle, Genetics, and Toxicity.

Science.gov (United States)

Jansen, Rick J; Argos, Maria; Tong, Lin; Li, Jiabei; Rakibuz-Zaman, Muhammad; Islam, Md Tariqul; Slavkovich, Vesna; Ahmed, Alauddin; Navas-Acien, Ana; Parvez, Faruque; Chen, Yu; Gamble, Mary V; Graziano, Joseph H; Pierce, Brandon L; Ahsan, Habibul

2016-02-01

Exposure to inorganic arsenic (iAs), a class I carcinogen, affects several hundred million people worldwide. Once absorbed, iAs is converted to monomethylated (MMA) and then dimethylated forms (DMA), with methylation facilitating urinary excretion. The abundance of each species in urine relative to their sum (iAs%, MMA%, and DMA%) varies across individuals, reflecting differences in arsenic metabolism capacity. The association of arsenic metabolism phenotypes with participant characteristics and arsenical skin lesions was characterized among 4,794 participants in the Health Effects of Arsenic Longitudinal Study (Araihazar, Bangladesh). Metabolism phenotypes include those obtained from principal component (PC) analysis of arsenic species. Two independent PCs were identified: PC1 appears to represent capacity to produce DMA (second methylation step), and PC2 appears to represent capacity to convert iAs to MMA (first methylation step). PC1 was positively associated (P 4.32/AS3MT region polymorphisms were strongly associated with PC1, but not PC2. Patterns of association for most variables were similar for PC1 and DMA%, and for PC2 and MMA% with the exception of arsenic exposure and SNP associations. Two distinct arsenic metabolism phenotypes show unique associations with age, sex, BMI, 10q24.32 polymorphisms, and skin lesions. This work enhances our understanding of arsenic metabolism kinetics and toxicity risk profiles. ©2015 American Association for Cancer Research.

Improvement of the T-peel Strength of Polypropylene Adhesion Joints by Surface Photografting Pre-Treatment with Methyl Methacrylate

Science.gov (United States)

Balart, R.; Sánchez-Nácher, L.; Balart, J.; Fombuena, V.; España, J. M.

2010-06-01

Although polypropylene is one of the most used polymers at industrial level due to good balanced properties, it presents some restrictions in applications that require good adhesion properties as well as coating and painting. These restrictions are related to its non polar nature which leads to low wetting properties. So that, in most cases, it is necessary a previous surface pre-treatment in order to improve adhesion properties. These surface treatments could be physical or chemical. Among the wide variety of physical processes, plasma technologies are useful from both technical and environmental points of view. If we take into account economic considerations, chemical processes are interesting due to low cost equipment and procedures. In particular, we have used photografting of methyl methacrylate (MMA) monomer on polypropylene substrates with UV radiation and initiators. This process is useful to promote chemical modification of polypropylene surface by grafting MMA monomers into polypropylene polymer chains. Due to polarity of some groups in MMA monomers, it is possible to increase surface wettability thus promoting a remarkable increase in adhesion properties of polypropylene. In this work, changes in wettability of polypropylene surfaces in terms of the exposure time to UV radiation in presence of MMA monomers and initiators has been investigated. Furthermore, chemical changes have been characterized by FTIR analysis and mechanical performance of adhesion joints has been evaluated by T-peel tests.

Electrical properties of poly(vinyl chloride) films stabilized with ter polymeric photo stabilizers containing UV-absorbing groups

International Nuclear Information System (INIS)

Eid, M.A.M.; Rabie, S.T.

2005-01-01

Some ter polymeric stabilizers based on polymerizable derivatives of 2,4-dihydroxybenzophenone and phenylsalicylate have been prepared and evaluated as photo stabilizers for rigid PVC. The prepared terpolymers which are namely, methylmethacrylate/2-hydroxyethylmethacrylate/4-methacryloxy- 2-hydroxybenzophenone (MMA/HEMA/HBMA), methylmethacrylate/ 2- Hydroxyethylmethacrylate/ 2-hydroxy-4-(3-methacrylo-xy-2- hydroxypropoxy) benzophenone (MMA/HEMA/PBMA) and methylmethacrylate / 2-Hydroxy-ethyl methacrylate / phenyl-5- methacryloxy methyl salicylate (MMA / HEMA / PMMS) were characterized and their structure were confirmed by GPC, FTIR and UV-VIS spectroscopy. The dielectric study was carried out over a frequency range from 100 Hz to 100 khz at room temperature(22 degree C). The results revealed that the stabilizing effect of these terpolymers depend on the type of stabilizer (terpolymer) and the content of UV absorber units in the terpolymer. The dielectric data for the investigated systems were found to be fitted by two absorption regions using Frohlich function. These regions ascribe the Maxwell.Wagner effect and the intramolecular motion involves the rotation of various segments of the side group as the main chain motion is restricted. The study led to a conclusion that MMA/HEMA/PBMA has the greatest stabilizing efficiency may be due to the relatively longer acrylic side chain in PBMA which makes the molecule more mobile and more flexible

Acidose metabólica na infância: por que, quando e como tratá-la? Metabolic acidosis in childhood: why, when and how to treat

Directory of Open Access Journals (Sweden)

Olberes V. B. Andrade

2007-05-01

Full Text Available OBJETIVO: Apresentar uma revisão atualizada e crítica sobre os mecanismos das principais patologias associadas e o tratamento da acidose metabólica, discutindo aspectos controversos quanto aos benefícios e riscos da utilização do bicarbonato de sódio e outras formas de terapia. FONTES DOS DADOS: Revisão da literatura publicada, obtida através de busca eletrônica com as palavras-chave acidose metabólica, acidose láctica, cetoacidose diabética, ressuscitação cardiopulmonar, bicarbonato de sódio e terapêutica nas bases de dados PubMed/MEDLINE, LILACS e Cochrane Library, entre 1996 e 2006, além de publicações clássicas referentes ao tema, sendo selecionadas as mais atuais e representativas, buscando-se consensos e diretrizes. SÍNTESE DOS DADOS: A utilização de bicarbonato de sódio não demonstra benefícios no quadro hemodinâmico, evolução clínica, morbidade e mortalidade nos quadros de acidose metabólica de anion gap elevado, relacionados à acidose láctica, cetoacidose diabética e ressuscitação cardiorrespiratória. Assim, a sua utilização rotineira não é indicada. Devem ser considerados os potenciais efeitos colaterais. O tratamento da doença de base é fundamental para reversão do processo. Outras terapias alternativas não demonstram efetividade comprovada em grande escala. CONCLUSÕES: Apesar dos efeitos conhecidos da acidemia em situações críticas no organismo, discute-se o papel protetor da acidemia nas células sob hipoxemia e os riscos da alcalemia secundária à intervenção medicamentosa. Existe consenso na reposição de álcalis e bicarbonato de sódio nos casos de acidose de anion gap normal; entretanto, nos casos de acidose de anion gap elevado, particularmente na acidose láctica, cetoacidose diabética e na ressuscitação cardiorrespiratória, o uso de bicarbonato de sódio não demonstra benefícios, além dos potenciais efeitos adversos, o que torna restrita sua indicação. Apesar da

A general review on vitamin B12 deficiency with focus on the situation in Jordan

International Nuclear Information System (INIS)

Qutob, M. S.; Takruri, H. R.

2011-01-01

Vitamin B 12 (cobalamin) is an essential nutrient that is only obtained from foods of animal origin, such as meat, eggs and dairy products. Vitamin B 12 plays an important role in DNA synthesis and neurological function. Thus its deficiency can lead to several neurological symptoms such as memory loss, dizziness and in severe cases may lead to dementia. Many factors can cause or lead to vitamin B-1 2 deficiency. Among these are malabsorption, several gastron intestinal problems (i.e. celiac disease, Crobn's disease) and gastrointestinal surgeries. diagnosis of vitamin B-1 2 status depends commonly on serum vitamin B 12 which is nonspecific tool for the deficiency. Other more specific tests, which reflect true deficiency, include serum and urine methylmalonic aci de, total serum homocysteine and serum holotranscobalamin. Vitamin B 12 deficiency is a worldwide public health problem; epidemiological studies showed that its prevalence in industrialized countries ranges from 5-60% of the population depending on the used cutoff point of cobalamin level. In Jordan, many reports were published on vitamin B 12 deficiency. However, these reports gave different results of its prevalence ranging from 16-48% depending on the serum vitamin B 12 cutoff point used. A recent study showed a prevalence of true deficiency of 32.7% based on measuring both serum vitamin B 12 level and plasma methylmalonic acid. (authors).

Three Arm Star Homo- And Co-Polymers Via Atom Transfer Radical Polymerization

International Nuclear Information System (INIS)

Amin, A.; Sobh, R.A.; Ayoub, M.M.H.

2005-01-01

Star homo and co-polymers of some vinyl monomers such as methylmethacrylate, butylmethacrylate and styrene (MMA, BMA, St.) were prepared using N, N, N', N' tetramethylethylenediamine ligand/ CuBr catalytic system via atom transfer radical polymerization (ATRP). Three armed benzene based core was successfully used as initiator. Low polydispersities and regular molecular weight values were obtained in most cases especially at low conversions. MMA and BuMA showed comparable behavior where controlled and true ATRP was observed even at the high conversions. However, styrene monomer recorded irregular high polydispersities at high conversions in spite of the relatively low molecular weight values. 1HNMR confirmed the structures of the resulting polymers. Transmission Electron microscope (TEM) proved the nano-structure of the star polymers. The thermal behavior of the MMA star homo and copolymers was studied. The effect of the star shape on the thermal behavior was very clear with respect to the linear ones

Organisk demens blandt tandteknikere. En tvaersnitundersøgelse af tandteknikere med optikere som kontrolgruppe

DEFF Research Database (Denmark)

Prescott, E; Steendahl, Ulla; Damsgaard, M T

1989-01-01

The preparation methyl metacrylate (MMA) an organic solvent which is employed inter alii in the production of prostheses, is regarded as neurotoxic. With the object of illustrating to what extent dental technicians have symptoms compatible with organic dementia as compared with a control group, a...... after very slight exposure. Revision of the occupational environment of dental technicians, including the current hygienic limits for MMA, is recommended.......The preparation methyl metacrylate (MMA) an organic solvent which is employed inter alii in the production of prostheses, is regarded as neurotoxic. With the object of illustrating to what extent dental technicians have symptoms compatible with organic dementia as compared with a control group......, a cross-sectional questionnaire investigation was undertaken in a population consisting of 256 dental technicians and 160 opticians, all of whom were professionally active. The percentage replies for the two groups were 88 and 85 respectively. The two groups do not differ from one another as regards...

Radiation graft copolymerization of styrene with m/e and styrene with acrylic acid at highthyl methacryl dose rate

International Nuclear Information System (INIS)

Aliev, R.Eh.; Kabanov, B.Ya.

1984-01-01

Comparative investigation of radiation graft copolymerization of styrene with methyl methacrylate (MMA) and styrene with acrylic acid (AA) is carried out at considerably differing radiation dose rates. The monomer mixture was grafted to PE low density films at dose rates of 0.16, 0.25 Gy/s (1 MeV electron acceleration). The value of graft was 3-6 and 5-10%, respectively, for the styrene-MMA and styrene-AA systems. An essential difference in the dependences of the formed copolymer composition on initial monomer mixture composition is noticed. Difference in composition of graft polymers prepared at different dose rates is less for the systems with AA, than for systems with MMA. It is shown that at high dose rates in difference with low ones not only radical graft copolymerization of the styrene mixture with AA takes place, but a contribution of the graft styrene polymerization according to cation mechanism as well

Synthesis and characterization of poly(styrene-co-methyl methacrylate); Sintese e caracterizacao do poli(estireno-co-metacrilato de metila)

Energy Technology Data Exchange (ETDEWEB)

Augustinho, Tiago R.; Abarca, Silvia A.C.; Machado, Ricardo A.F. [Departamento de Engenharia Quimica e Alimentos - Universidade Federal de Santa Catarina - UFSC, Florianopolis, SC (Brazil)

2011-07-01

Polystyrene (PS) is nowadays commonly used due its advantages over competitors. PS presents a lower cost when compared with Acrylonitrile Butadiene Styrene (ABS) and with Polyethylene Tere-phthalate (PET), and can be easier processed than polypropylene (PP). At expandable form (EPS), can be used as projective equipment, thermal insulation, floating boards, refrigerators, isothermal, and low cost applications such as packaging and disposable material. Searching for more resistant materials and with a low cost, researches with copolymers materials are being developed. In this study, copolymerization reactions were carried out by suspension polymerization using monomers styrene and methyl methacrylate (MMA) with styrene. Styrene was in the highest percentage in relation to the MMA. The MMA was selected because is a monomer that presents a higher resistance than PS. The copolymerization was confirmed by performing infrared spectroscopy (IR), nuclear magnetic resonance of hydrogen (RMN{sup 1}H), differential scanning calorimetry (DSC) and thermogravimetry (TGA). (author)

Graft Copolymerization Of Methyl Methacrylate Onto Agave Cellulose

International Nuclear Information System (INIS)

Noor Afizah Rosli; Ishak Ahmad; Ibrahim Abdullah; Farah Hannan Anuar

2014-01-01

The grafting polymerization of methyl methacrylate (MMA) and Agave cellulose was prepared and the grafting reaction conditions were optimized by varying the reaction time and temperature, and ratio of monomer to cellulose. The resulting graft copolymers were characterized by Fourier transform infrared, X-ray diffraction analysis, thermogravimetric analysis, and scanning electron microscopy (SEM). The experimental results showed that the optimal conditions were at a temperature of 45 degree Celsius for 90 min with ratio monomer to cellulose at 1:1 (g/ g). An additional peak at 1738 cm -1 which was attributed to the C=O of ester stretching vibration of poly(methyl methacrylate), appeared in the spectrum of grafted Agave cellulose. A slight decrease of crystallinity index upon grafting was found from 0.74 to 0.68 for cellulose and grafted cellulose, respectively. Grafting of MMA onto cellulose enhanced its thermal stability and SEM observation further furnished evidence of grafting MMA onto Agave cellulose with increasing cellulose diameter and surface roughness. (author)

Adsorption behavior of protein onto siloxane microspheres

International Nuclear Information System (INIS)

Liu Bailing; Cao Shunsheng; Deng Xiaobo; Li Songjun; Luo Rong

2006-01-01

The siloxane microspheres with core-shell structure (PMMA/PMPS) (MMA, methyl methacrylate; MPS, 3-methacryloxypropyl-trimethoxysilane) have been prepared by dispersion polymerization as described in our previous work. In this paper, the developed poly(MMA-MPS) microspheres, as a carrier, are used to investigate the adsorption behavior of bovine serum albumin (BSA) on them. The Langmuir and Freundlich models have been applied to describe the adsorption behavior. The experimental results indicated that the presence of PMPS evidently increases the adsorption rate and the amount of protein, and it also influences the interaction of BSA molecules. The adsorption of BSA on the poly(MMA-MPS) microspheres seems to be sensitive to pH and ionic strength. The fittings curves from Langmuir and Freundlich models showed that the adsorption was actually more complicated than ideal situation because one or more interactions were involved in the process. For understanding the electronic contribution, the Zeta potential was used to measure the reactive system before and after protein adsorption

A study on meme propagation in multimemetic algorithms

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Nogueras Rafael

2015-09-01

Full Text Available Multimemetic algorithms (MMAs are a subclass of memetic algorithms in which memes are explicitly attached to genotypes and evolve alongside them. We analyze the propagation of memes in MMAs with a spatial structure. For this purpose we propose an idealized selecto-Lamarckian model that only features selection and local improvement, and study under which conditions good, high-potential memes can proliferate. We compare population models with panmictic and toroidal grid topologies. We show that the increased takeover time induced by the latter is essential for improving the chances for good memes to express themselves in the population by improving their hosts, hence enhancing their survival rates. Experiments realized with an actual MMA on three different complex pseudo-Boolean functions are consistent with these findings, indicating that memes are more successful in a spatially structured MMA, rather than in a panmictic MMA, and that the performance of the former is significantly better than that of its panmictic counterpart

Adsorption behavior of protein onto siloxane microspheres

Energy Technology Data Exchange (ETDEWEB)

Liu Bailing [Chengdu Institute of Organic Chemistry, Graduate School of CAS, Chinese Academy of Sciences, Chengdu 610041 (China)]. E-mail: Blliuchem@hotmail.com; Cao Shunsheng [Chengdu Institute of Organic Chemistry, Graduate School of CAS, Chinese Academy of Sciences, Chengdu 610041 (China); Deng Xiaobo [Chengdu Institute of Organic Chemistry, Graduate School of CAS, Chinese Academy of Sciences, Chengdu 610041 (China); Li Songjun [Chengdu Institute of Organic Chemistry, Graduate School of CAS, Chinese Academy of Sciences, Chengdu 610041 (China); Luo Rong [Chengdu Institute of Organic Chemistry, Graduate School of CAS, Chinese Academy of Sciences, Chengdu 610041 (China)

2006-09-15

The siloxane microspheres with core-shell structure (PMMA/PMPS) (MMA, methyl methacrylate; MPS, 3-methacryloxypropyl-trimethoxysilane) have been prepared by dispersion polymerization as described in our previous work. In this paper, the developed poly(MMA-MPS) microspheres, as a carrier, are used to investigate the adsorption behavior of bovine serum albumin (BSA) on them. The Langmuir and Freundlich models have been applied to describe the adsorption behavior. The experimental results indicated that the presence of PMPS evidently increases the adsorption rate and the amount of protein, and it also influences the interaction of BSA molecules. The adsorption of BSA on the poly(MMA-MPS) microspheres seems to be sensitive to pH and ionic strength. The fittings curves from Langmuir and Freundlich models showed that the adsorption was actually more complicated than ideal situation because one or more interactions were involved in the process. For understanding the electronic contribution, the Zeta potential was used to measure the reactive system before and after protein adsorption.

A Historical Overview of Mixed Martial Arts in China

OpenAIRE

William Acevedo; Mei Cheung

2012-01-01

Mixed martial arts (MMA) has become one of the fastest-growing combat sports in the twenty-first century, drawing millions of Pay-Per-View spectators since the inception of the Ultimate Fighting Championship (UFC) in 1993. Popular conceptions have credited the creation of MMA to Bruce Lee, a Chinese-American actor and martial artist who became an icon in the 1970s and who is still considered by many as a revolutionary figure in the field. This paper will present, in chronological order, examp...

Urinary arsenic levels in the French adult population: the French National Nutrition and Health Study, 2006-2007.

Science.gov (United States)

Saoudi, Abdessattar; Zeghnoun, Abdelkrim; Bidondo, Marie-Laure; Garnier, Robert; Cirimele, Vincent; Persoons, Renaud; Fréry, Nadine

2012-09-01

The French Nutrition and Health Survey (ENNS) was conducted to describe dietary intakes, nutritional status, physical activity, and levels of various biomarkers for environmental chemicals (heavy metals and pesticides) in the French population (adults aged 18-74 years and children aged 3-17 years living in continental France in 2006-2007). The aim of this paper was to describe the distributions of total arsenic and the sum of iAs+MMA+DMA in the general adult population, and to present their main risk factors. In the arsenic study, 1500 and 1515 adults (requested to avoid seafood intake in the previous 3 days preceding urine collection) were included respectively for the analysis of the sum of inorganic arsenic (iAs) and its two metabolites, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), and for the total arsenic. Results were presented as geometric means and selected percentiles of urinary arsenic concentrations (μg/L) and creatinine-adjusted urinary arsenic (μg/g of creatinine) for total arsenic, and the sum of inorganic arsenic and metabolites (iAs+MMA+DMA). The geometric mean concentration of the sum of iAs+MMA+DMA in the adult population living in France was 3.34 μg/g of creatinine [3.23-3.45] (3.75 μg/L [3.61-3.90]) with a 95th percentile of 8.9 μg/g of creatinine (10.68 μg/L). The geometric mean concentration of total arsenic was 11.96 μg/g of creatinine [11.41-12.53] (13.42 μg/L [12.77-14.09]) with a 95th percentile of 61.29 μg/g of creatinine (72.75 μg/L). Urinary concentrations of total arsenic and iAS+MMA+DMA were influenced by sociodemographic and economic factors, and by risk factors such as consumption of seafood products and of wine. In our study, covariate-adjusted geometric means demonstrated several slight differences, due to consumption of fish, shellfish/crustaceans or wine. This study provides the first reference value for arsenic in a representative sample of the French population not particularly exposed to high levels

Arsenic methylation capacity is associated with breast cancer in northern Mexico

Energy Technology Data Exchange (ETDEWEB)

López-Carrillo, Lizbeth; Hernández-Ramírez, Raúl Ulises [Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México (Mexico); Gandolfi, A. Jay [Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ (United States); Ornelas-Aguirre, José Manuel [Unidad de Investigación en Epidemiología Clínica del Hospital de Especialidades No. 2, Unidad Médica de Alta Especialidad, Instituto Mexicano del Seguro Social, Ciudad Obregón, Sonora, México (Mexico); Torres-Sánchez, Luisa [Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México (Mexico); Cebrian, Mariano E., E-mail: mcebrian@cinvestav.mx [Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, México City, México (Mexico)

2014-10-01

Exposure to environmental contaminants, dietary factors and lifestyles may explain worldwide different breast cancer (BC) incidence. Inorganic arsenic (iAs) in the drinking water is a concern in many regions, such as northern Mexico. Studies in several countries have associated the proportion of urinary monomethylarsenic (%MMA) with increased risks for many As-related diseases, including cancer. To investigate the potential relationships between the risk of BC and the capacity to methylate iAs, a hospital-based case–control study (1016 cases/1028 controls) was performed in northern Mexico. Women were directly interviewed about their reproductive histories. The profile of As metabolites in urine was determined by HPLC-ICP-MS and methylation capacity was assessed by metabolite percentages and indexes. Total urinary As, excluding arsenobetaine (TAs-AsB), ranged from 0.26 to 303.29 μg/L. Most women (86%) had TAs-AsB levels below As biological exposure index (35 μg/L). Women with higher %MMA and/or primary methylation index (PMI) had an increased BC risk (%MMA OR{sub Q5vs.Q1} = 2.63; 95%CI 1.89,3.66; p for trend < 0.001; PMI OR{sub Q5vs.Q1} = 1.90; 95%CI 1.39,2.59, p for trend < 0.001). In contrast, women with higher proportion of urinary dimethylarsenic (%DMA) and/or secondary methylation index (SMI) had a reduced BC risk (%DMA OR{sub Q5vs.Q1} = 0.63; 95%CI 0.45,0.87, p for trend 0.006; SMI OR{sub Q5vsQ1} = 0.42, 95%CI 0.31,0.59, p for trend < 0.001). Neither %iAs nor total methylation index was associated to BC risk. Inter-individual variations in iAs metabolism may play a role in BC carcinogenesis. Women with higher capacity to methylate iAs to MMA and/or a lower capacity to further methylate MMA to DMA were at higher BC risk. - Highlights: • Arsenic methylation capacity is associated to an increased breast cancer (BC) risk. • Women with higher capacity to methylate arsenic to MMA were at higher BC risk. • Women with higher capacity to methylate arsenic to

Expression of selected pathway-marker genes in human urothelial cells exposed chronically to a non-cytotoxic concentration of monomethylarsonous acid

Directory of Open Access Journals (Sweden)

Matthew Medeiros

2014-01-01

Full Text Available Bladder cancer has been associated with chronic arsenic exposure. Monomethylarsonous acid [MMA(III] is a metabolite of inorganic arsenic and has been shown to transform an immortalized urothelial cell line (UROtsa at concentrations 20-fold less than arsenite. MMA(III was used as a model arsenical to examine the mechanisms of arsenical-induced transformation of urothelium. A previous microarray analysis revealed only minor changes in gene expression at 1 and 2 months of chronic exposure to MMA(III, contrasting with substantial changes observed at 3 months of exposure. To address the lack of information between 2 and 3 months of exposure (the critical period of transformation, the expression of select pathway marker genes was measured by PCR array analysis on a weekly basis. Cell proliferation rate, anchorage-independent growth, and tumorigenicity in SCID mice were also assessed to determine the early, persistent phenotypic changes and their association with the changes in expression of these selected marker genes. A very similar pattern of alterations in these genes was observed when compared to the microarray results, and suggested that early perturbations in cell signaling cascades, immunological pathways, cytokine expression, and MAPK pathway are particularly important in driving malignant transformation. These results showed a strong association between the acquired phenotypic changes that occurred as early as 1–2 months of chronic MMA(III exposure, and the observed gene expression pattern that is indicative of the earliest stages in carcinogenesis.

Variability in human metabolism of arsenic

International Nuclear Information System (INIS)

Loffredo, C.A.; Aposhian, H.V.; Cebrian, M.E.; Yamauchi, Hiroshi; Silbergeld, E.K.

2003-01-01

Estimating the nature and extent of human cancer risks due to arsenic (As) in drinking water is currently of great concern, since millions of persons worldwide are exposed to arsenic, primarily through natural enrichment of drinking water drawn from deep wells. Humans metabolize and eliminate As through oxidative methylation and subsequent urinary excretion. While there is debate as to the role of methylation in activation/detoxification, variations in arsenic metabolism may affect individual risks of toxicity and carcinogenesis. Using data from three populations, from Mexico, China, and Chile, we have analyzed the distribution in urine of total arsenic and arsenic species (inorganic arsenic (InAs), monomethyl arsenic (MMA), and dimethyl arsenic (DMA). Data were analyzed in terms of the concentration of each species and by evaluating MMA:DMA and (MMA+DMA):InAs ratios. In all persons most urinary As was present as DMA. Male:female differences were discernible in both high- and low-exposure groups from all three populations, but the gender differences varied by populations. The data also indicated bimodal distributions in the ratios of DMA to InAs and to MMA. While the gene or genes responsible for arsenic methylation are still unknown, the results of our studies among the ethnic groups in this study are consistent with the presence of functional genetic polymorphisms in arsenic methylation leading to measurable differences in toxicity. This analysis highlights the need for continuing research on the health effects of As in humans using molecular epidemiologic methods

Analytical calculations and properties of gamma-rays polymerization of novel acrylates copolymer system

Energy Technology Data Exchange (ETDEWEB)

El-Sayed, S.M., E-mail: smelsayed@hotmail.co [National Center for Radiation Research and Technology, Nasr City, Cairo (Egypt); Madani, M.; El-Bayoumi, A.S. [National Center for Radiation Research and Technology, Nasr City, Cairo (Egypt)

2009-11-15

A detailed study of some physical properties of pure PMMA (polymethyl methacrylate) film and MMA/Ani (methyl methacrylate/aniline) films is presented. Films of thicknesses ranged from 0.04 to 0.72 mm for MMA/Ani were prepared while it is 0.68 mm for PMMA. The structure of the sample is analyzed by X-ray diffraction technique and is found to be amorphous (PMMA) and partially crystalline (MMA/Ani). Ultra violet-visible electronic absorption spectra measurements were analyzed to obtain some important parameters such as molar extrication coefficient, oscillator strength, dipole strength and having good thermal stability (T{sub d} >300 deg. C) was also reported. TGA studies revealed that the thermal stability of polymethyl methacrylate, prepared by radiation polymerization of methyl methacrylate, improved after copolymerization with aniline. Also, optical behavior of film samples was analyzed by obtaining transmission spectra, in the wavelength range of 200-1100 nm. It was found that all studied samples lead to the appearance of a second edge at lower photon energy due to the formation of the induced energy states. From the intensity of absorption interband transitions (B and Q) which are assigned as type pi-pi* for both PMMA and MMA/Ani films, the energy gaps E{sub g1} and E{sub g2} were calculated respectively. The optical conductivity (sigma) was determined and it was found that with the increase of thicknesses optical energy gap decreases monotonically and the refractive index increases.

Analysis of Tidal Data for Dagang Tidal Gauge and Study of the Changes for the National Height Datum

Directory of Open Access Journals (Sweden)

WU Fumei

2015-07-01

Full Text Available The main tides affecting Dagang sea level are analyzed and the national height datum is studied by analyzing 1980—2011 hourly tidal data and 1952—2007 monthly mean tidal data. Firstly, the frequencies and amplitudes of main tides including 180 short-period tides and 6 long-period tides are gained by the Fouirer transform. Then the actual amplitudes and their variations of main tides are obtained by the harmonic analysis of the 1980—2011 hourly tidal data, and the changes with about 19 year period can easily be found in the amplitudes of Q1、O1、M2、K1、K2. And then the changes of the mean sea level at Dagang tidal gauge defining national height datum during the period of 1952—2011 are studied by the harmonic analysis and the shifting average of 18.61 year tidal heights. The results of these methods show that the mean sea level at Dagang tidal gauge descended with the speed of 1.07 mm/a and 0.76 mm/a respectively during 1952—1980, and that it ascended with the speed of 1.59 mm/a and 1.62 mm/a respectively during 1980—2011. And finally the difference of 0.14 cm is achieved by the shifting average of 18.61 year tidal heights for 1985 National Height Datum.

Synthesis and properties of silane-fluoroacrylate grafted starch.

Science.gov (United States)

Qu, Jia; He, Ling

2013-10-15

The latex of silane-fluoroacrylate grafted starch for coating materials, VTMS-starch/P(MMA/BA/3FMA), is obtained by two step grafting reactions. Vinyltrimethoxysilane (VTMS) is primarily grafted onto starch by condensation between Si-OH and C-OH at 120 °C, and then the copolymer of methyl methacrylate (MMA), butyl acrylate (BA) and 2,2,2-trifluoroethyl methacrylate (3FMA) is grafted onto the VTMS-starch by emulsion polymerization. Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS) have been used to confirm the chemically grafting reactions in every step. The conversion percent, grafting percent and grafting efficiency for VTMS-starch/p(MMA/BA/3FMA) latex indicate that the optimum conditions should be controlled at 75 °C for 1h as VTMS-starch/P(MMA/BA/3FMA) in 1/3 weight ratio. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis have revealed that the latexes exhibit the uniform spherical particles of 40-60 nm in a narrow size distribution. The latex films perform the obvious hydrophobic (107°) property, lower surface free energy (25-35 mN/m) and the higher thermostability (330-440 °C) than starch (51°, 51.32 mN/m, 100-330 °C). Dynamic thermomechanical analysis (DMA) shows that the latex film could gain considerable toughness and strength with an elongation at break of 39.45% and a tensile strength of 11.97 MPa. Copyright © 2013 Elsevier Ltd. All rights reserved.

Injury profile of mixed martial arts competitors.

Science.gov (United States)

McClain, Rance; Wassermen, Jason; Mayfield, Carlene; Berry, Andrew C; Grenier, Greg; Suminski, Richard R

2014-11-01

To provide an updated comprehensive profile of mixed martial arts (MMAs) injuries. Correlational and multivariate analyses were conducted on cross-sectional data to examine injuries sustained during 711 MMA bouts. One physician diagnosed any injuries occurring during the bouts. Various sports venues in Kansas and Missouri holding MMA competitions. Male and female and amateur and professional MMA competitors contributing to 1422 fight participations (fight participations = 711 bouts × 2 fighters/bout). State, level (amateur or professional), gender, number of rounds, and bout outcome (knockout/technical knockout [KO/TKO] vs other outcomes [eg, decision]). Injuries/fight participations, injury sustained (yes vs no), and fighter referred to emergency room (ER; yes vs no). The overall injury rate was 8.5% of fight participations (121 injuries/1422 fight participations) or 5.6% of rounds (121/2178 rounds). Injury rates were similar between men and women, but a greater percentage of the injuries caused an altered mental state in men. The risk of being injured was significantly greater for bouts held in Kansas, at the professional level, lasting more rounds, and ending in a KO/TKO. Fighters also were more likely to be referred to the ER if they participated in longer bouts ending in a KO/TKO. The observed injury rate was lower than previously reported suggesting recent regulatory changes have made MMA a safer sport. Increased clinical awareness and additional research should be extended to head-related injuries in MMAs especially those associated with KOs/TKOs.

Nrf2 protects human bladder urothelial cells from arsenite and monomethylarsonous acid toxicity

International Nuclear Information System (INIS)

Wang Xiaojun; Sun Zheng; Chen Weimin; Eblin, Kylee E.; Gandolfi, Jay A.; Zhang, Donna D.

2007-01-01

Arsenic is widely spread in our living environment and imposes a big challenge on human health worldwide. Arsenic damages biological systems through multiple mechanisms including the generation of reactive oxygen species. The transcription factor Nrf2 regulates the cellular antioxidant response that protects cells from various insults. In this study, the protective role of Nrf2 in arsenic toxicity was investigated in a human bladder urothelial cell line, UROtsa. Using a UROtsa cell line stably infected with Nrf2-siRNA, we clearly demonstrate that compromised Nrf2 expression sensitized the cells to As(III)- and MMA(III)-induced toxicity. On the other hand, the activation of the Nrf2 pathway by tert-butylhydroquinone (tBHQ) and sulforaphane (SF), the known Nrf2-inducers, rendered UROtsa cells more resistant to As(III) and MMA(III). Furthermore, the wild-type mouse embryo fibroblast (WT-MEF) cells were protected from As(III)- and MMA(III)-induced toxicity following Nrf2 activation by tBHQ or SF, whereas neither tBHQ nor SF conferred protection in the Nrf2 -/- MEF cells, demonstrating that tBHQ- or SF-mediated protection against As(III)- and MMA(III)-induced toxicity depends on Nrf2 activation. These results, obtained by both loss of function and gain of function analyses, clearly demonstrate the protective role of Nrf2 in arsenic-induced toxicity. The current work lays the groundwork for using Nrf2 activators for therapeutic and dietary interventions against adverse effects of arsenic

POLYMERIZATION OF METHYL METHACRYLATE WITH ETHYLENE BRIDGED HETERODINUCLEAR METALLOCENE OF SAMARIUM AND TITANIUM-STUDY ON SYNERGISM AND KINETICS

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

Comparison of MMA polymerization results with samarocene chloride, titanocene chloride and the title heterodinuclear (Sm-Ti) catalyst, respectively, showed synergism in the Sm-Ligand-Ti system, which ob viously influenced the polymerization behaviors, for example, of yielding higher activity and higher molecular weight polymer. Kinetic studies on polymerization of MMA with ethylene bridged samarocene and titanocene chloride/M(i-Bu) 3 showed that the polymerization rate was first-order on the catalyst concentration, and 1.9- order on the monomer. The overall activation energy measured was 52.8 kJ/mol.

Local Genealogies in a Linear Mixed Model for Genome-wide Association Mapping in Complex Pedigreed Populations

DEFF Research Database (Denmark)

Sahana, Goutam; Mailund, Thomas; Lund, Mogens Sandø

2011-01-01

be extended to incorporate other effects in a straightforward and rigorous fashion. Here, we present a complementary approach, called ‘GENMIX (genealogy based mixed model)’ which combines advantages from two powerful GWAS methods: genealogy-based haplotype grouping and MMA. Subjects and Methods: We validated......Introduction: The state-of-the-art for dealing with multiple levels of relationship among the samples in genome-wide association studies (GWAS) is unified mixed model analysis (MMA). This approach is very flexible, can be applied to both family-based and population-based samples, and can...

Systematic review of injuries in mixed martial arts.

Science.gov (United States)

Thomas, Roger E; Thomas, Bennett C

2018-01-25

To assess injury rates in all mixed martial arts (MMA) studies. Six online databases were searched until November 2017 including MEDLINE, EMBASE, CINAHL, Web of Science, PubMed, Google/Google Scholar and conference proceedings. All included studies were entered in Pub Med Single Citation Matcher and all citation chains followed. Abstracts and titles were assessed for relevance, data independently abstracted and risk of bias for all competition studies evaluated independently by two reviewers. There are data for 5,374 male and 108 female MMA fighters. For 2407 males the weighted average injury rate/1000Athletic Encounters (AE) was 246.4 and for one study of 108 females 101.9. One study provided data by professional status: professionals 135.5/1000AE and amateurs 71.0/1000AE. Reasons for stopping matches were knockout/technical knockout 173.9/1000AE for males and 175.9/1000AE for females, submission 228.6/1000AE, and referee's decision 98.2/1000AE. Losers can experience large amounts of trauma especially head trauma as matches terminate. Two studies of competitions provided personally conducted ringside assessments and both pre- and post-match examination results. The other studies reported retrospective assessments of fight records or videos or videos and scorecards. There are no studies of training injuries of professionals or injuries of amateurs or long-term follow-up of musculoskeletal injuries or neurological damage. Studies are limited to the US and Canada. There are no systematic reviews of newspaper or media accounts of fights to assess rates and numbers of injuries or mortality. The few published surveys and case reports markedly understate the worldwide situation. There are high rates of trauma in MMA. The authorities who regulate MMA and referees and physicians who monitor MMA fighters have an inadequate database to guide their work. Researchers need to adopt the same set of complete definitions of all possible injuries and measure the high and early rate

A study on mobile PC display design in NPP maintenance considering the level of expertise

International Nuclear Information System (INIS)

Kim, In

2010-02-01

Recently, the importance of effective maintenance in nuclear power plants (NPPs) has been emphasized and research into effective maintenance by adopting mobile maintenance aids (MMAs) have been attempted. MMAs are currently used during operation and maintenance in NPPs, but no method that considers the limitations of mobile devices has been proposed. For improved and effective use, an MMA display design method based on abstraction hierarchy (AH) is proposed and its design considerations are discussed in this study. Six levels of abstraction hierarchy are proposed in this paper to classify the maintenance information. By classifying and organizing maintenance information using AH, maintenance information can be used effectively by users either high or low levels of expertise. When information classification has been finished, the information requirements and relationships for MMA design is extracted from the analysis of the AH result. Representative human-machine interface (HMI) guidelines issued by the US NRC, which are generally used in NPPs, are applied. With the considerations of MMA design analysis and practical guidelines, AH-based MMA is designed for maintenance tasks. An experiment is conducted using the AH-based MMA in order to estimate the effectiveness of the proposed method for maintenance tasks and to identify design considerations to enhance the proposed MMAs. The result indicated that an AH-based manual was more effective than a conventional manual in terms of task completion time and number of errors. The workload for the AH-based manual was estimated to be less than the conventional manual for low levels of expertise. However, a conventional manual was more comprehensive than the proposed manual and the steps contained in the maintenance manual were easier to remember. As the level of expertise increases, subjects tended to follow more abstract information while the number of navigations decreased. It is believed that when mobile devices become

A case of asymptomatic pancytopenia with clinical features of hemolysis as a presentation of pernicious anemia

Directory of Open Access Journals (Sweden)

Venkateswara K. Kollipara

2016-09-01

Full Text Available Pernicious anemia is an autoimmune disease with a variety of clinical presentations. We describe a case of pernicious anemia presenting with pancytopenia with hemolytic features. Further workup revealed very low vitamin B12 levels and elevated methylmalonic acid. It is important for a general internist to identify pernicious anemia as one of the cause of pancytopenia and hemolytic anemia to avoid extensive workup. Pernicious anemia can present strictly with hematological abnormalities without neurological problems or vice versa as in our case.

Nationwide survey of rotavirus-associated encephalopathy and sudden unexpected death in Japan.

Science.gov (United States)

Kawamura, Yoshiki; Ohashi, Masahiro; Ihira, Masaru; Hashimoto, Shuji; Taniguchi, Koki; Yoshikawa, Tetsushi

2014-08-01

Rotavirus can cause severe complications such as encephalopathy/encephalitis and sudden unexpected death. The incidence of rotavirus-associated encephalopathy/encephalitis or sudden unexpected death remains unknown. To clarify the clinical features of rotavirus-associated encephalitis/encephalopathy and sudden unexpected death, we conducted a nationwide survey in Japan. A two-part questionnaire was designed to determine the number of the cases and the clinical features of severe cases of rotavirus infection, including encephalitis/encephalopathy and sudden unexpected death, between 2009 and 2011. Of the 1365 questionnaires sent to hospitals, 963 (70.5%) were returned and eligible for analysis. We determined 58 cases of rotavirus-associated encephalitis/encephalopathy and 7 cases of sudden unexpected death. These patients were diagnosed with rotavirus infection by immunochromatography. Although 36/58 (62.1%) encephalitis/encephalopathy patients had no sequelae, 15/58 (25.9%) patients had neurological sequelae, and 7/58 (12.1%) patients had fatal outcomes. Pleocytosis was observed in 9/40 (22.5%) patients and cerebrospinal fluid protein levels were elevated in only 4/40 (10%) patients. Elevated lactate dehydrogenase (LDH) (>500 IU/L) or acidemia (pHdeath were 44.0 and 4.9 cases in Japan, respectively. Elevated LDH (>500 IU/L) or acidemia (pH<7.15) were related to a poor prognosis of the encephalitis/encephalopathy. Copyright © 2013 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Terpolymers

Directory of Open Access Journals (Sweden)

M.A. Semsarzadeh

2009-12-01

Full Text Available The microstructure and thermal properties of the synthesized block copolymers and terpolymers via atom transfer radical polymerization (ATRP were studied. The mole fraction of the blocks and chain length of the PVAc-b-PMA block copolymers were estimated with 1H NMR spectroscopy.Differential scanning calorimety measurement shows two different transitions at 36°C and 8°C assigned to PVAc and PMA blocks. Thermogravimetric analysis demonstrated the similar thermal degradation behavior of the block copolymers and a three-step degradation around 238, 295 and 345°C were attributed to dechlorination step and decomposition of the PVAc and PMA blocks. Study of thermal properties of PVAc-b-Poly(MA-co-MMA copolymers indicated that glass transition temperature of second block increased from 49°C to 91°C with increase in MMA mole fraction from 0.358 to 0.733. The losses in the thermal degradation of block terpolymers were similar, and the higher thermal degredation temperature of MA unit has delayed the thermal degredation temperature of MMA in copolymer.

Inducing β Phase Crystallinity in Block Copolymers of Vinylidene Fluoride with Methyl Methacrylate or Styrene

Directory of Open Access Journals (Sweden)

Nahal Golzari

2017-07-01

Full Text Available Block copolymers of poly(vinylidene fluoride (PVDF with either styrene or methyl methacrylate (MMA were synthesized and analyzed with respect to the type of the crystalline phase occurring. PVDF with iodine end groups (PVDF-I was prepared by iodine transfer polymerization either in solution with supercritical CO2 or in emulsion. To activate all iodine end groups Mn2(CO10 is employed. Upon UV irradiation Mn(CO5 radicals are obtained, which abstract iodine from PVDF-I generating PVDF radicals. Subsequent polymerization with styrene or methyl methacrylate (MMA yields block copolymers. Size exclusion chromatography and NMR results prove that the entire PVDF-I is converted. XRD, FT-IR, and differential scanning calorimetry (DSC analyses allow for the identification of crystal phase transformation. It is clearly shown that the original α crystalline phase of PVDF-I is changed to the β crystalline phase in case of the block copolymers. For ratios of the VDF block length to the MMA block length ranging from 1.4 to 5 only β phase material was detected.

Self-supported poly(methyl methacrylate-acrylonitrile-vinyl acetate)-based gel electrolyte for lithium ion battery

Energy Technology Data Exchange (ETDEWEB)

Liao, Y.H.; Zhou, D.Y.; Rao, M.M.; Cai, Z.P.; Liang, Y. [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Li, W.S.; Tan, C.L. [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Key Lab of Electrochemical Technology on Energy Storage and Power Generation in Guangdong Universities, Guangzhou 510006 (China)

2009-04-01

Self-supported gel polymer electrolyte (GPE) was prepared based on copolymer, poly(methyl methacrylate-acrylonitrile-vinyl acetate) (P(MMA-AN-VAc)). The copolymer P(MMA-AN-VAc) was synthesized by emulsion polymerization and the copolymer membrane was prepared through phase inversion. The structure and the performance of the copolymer, the membrane and the GPE were characterized by FTIR, NMR, SEM, XRD, DSC/TG, LSV, CA, and EIS. It is found that the copolymer was formed through the breaking of double bond C=C in each monomer. The membrane has low crystallinity and has low glass transition temperature, 39.1 C, its thermal stability is as high as 310 C, and its mechanical strength is improved compared with P(MMA-AN). The GPE is electrochemically stable up to 5.6 V (vs. Li/Li{sup +}) and its conductivity is 3.48 x 10{sup -3} S cm{sup -1} at ambient temperature. The lithium ion transference number in the GPE is 0.51 and the conductivity model of the GPE is found to obey the Vogel-Tamman-Fulcher (VTF) equation. (author)

Some reflections on human needs, peace, transculturality and Igbo proverbs in the light of Emmanuel Edeh's African philosophy.

Science.gov (United States)

Prstačić, Miroslav

2015-03-01

Within the framework of a transcultural, psychodynamic and holistic approach, Edeh's concept of Man as Mma-di (in Igbo language in Nigeria, mma-di = good that is, and mma-ndu = the beauty of Life) is presented as the nucleus of his philosophical articulation from an African metaphysical-anthropological perspective. In this context, some reflections are shown on the following topics: human creativity and peace... of mind, body and soul, as existential values and entity in bioethics; aspects of Edeh's philosophy and his work on the peace in the world; transculturality and Igbo proverbs shaped in form of Japanese Haiku poetry. These reflections emphasize the importance of induced aesthetic mental state in the subject, which derives from biological impulses but from archetypal and symbolic value of the object and continuously enter into a metaphysical experience as a form of life energy and human existential need. In this context, we discover also Edeh's philosophy as a new stimulus for further reflections and research on human life potentials, creativity, peace and Man's cosmic responsibility.

Realizacija računarske mreže vojnomedicinske akademije / Medical military academy information system management

Directory of Open Access Journals (Sweden)

Miroslav Stojanović

2005-01-01

Full Text Available Vojnomedicinska akademija (VMA u Beogradu danas se ne može zamisliti bez kvalitetnog informacionog sistema, koji se najčešće razvija u sistemu računarske mreže. Cilj ovoga rada je da prikaže smernice i definiše neka rešenja u implementaciji buduće računarske mreže VMA. Težište rada je na implementaciji prva tri nivoa OSI modela jedne složene i kompleksne mreže kakva bi trebalo da bude računarska mreža VMA. / The Medical Military Academy (MMA in Belgrade cannot be imagined without a high-quality information system implemented in a corresponding computer network. The aim of this study is to show guidelines and possible solutions in implementing a computer network in to the MMA in the future. The main part of this study describes the implementation of the first three levels of the OSI model into the complex MMA computer network.

Stereocontrol during the radical polymerization of methyl methacrylates with combined Lewis acids:Aluminium trichloride（AlCl3） and iron dichloride tetrahydrate

Institute of Scientific and Technical Information of China (English)

无

2010-01-01

The radical polymerization of methyl methacrylate(MMA) was carried out in the presence of combined Lewis acids of the AlCl3-FeCl2 system.Compared with the polymerization produced in the presence of single Lewis acids,AlCl3 or FeCl2,the MMA polymerization in the presence of AlCl3-FeCl2 composite in CHCl3 or 1-butanol produced a polymer with a higher isotacticity and in toluene produced a polymer with a much higher isotacticity(mm=50%) .The molecular weight and polydispersity of PMMA in the presence of Lewis acids were similar with those in the absence of Lewis acids,although Lewis acids decelerate the polymerization of MMA.The effects of the Lewis acids were greater in a solvent with a lower polarity.A possible stereocontrol mechanism of the polymerization was proposed.The Lewis acid composite of AlCl3-FeCl2 readily formed a complex with growing species.These complexes possessed apparent bulkiness that changes the direction of monomer addition to the growing radical center.

Arsenic speciation in hair and nails of acute promyelocytic leukemia (APL) patients undergoing arsenic trioxide treatment.

Science.gov (United States)

Chen, Baowei; Cao, Fenglin; Lu, Xiufen; Shen, Shengwen; Zhou, Jin; Le, X Chris

2018-07-01

Arsenic in hair and nails has been used to assess chronic exposure of humans to environmental arsenic. However, it remains to be seen whether it is appropriate to evaluate acute exposure to sub-lethal doses of arsenic typically used in therapeutics. In this study, hair, fingernail and toenail samples were collected from nine acute promyelocytic leukemia (APL) patients who were administered intravenously the daily dose of 10 mg arsenic trioxide (7.5 mg arsenic) for up to 54 days. These hair and nail samples were analyzed for arsenic species using high performance liquid chromatography separation and inductively coupled plasma mass spectrometry detection (HPLC-ICPMS). Inorganic arsenite was the predominant form among water-extractable arsenicals. Dimethylarsinic acid (DMA V ), monomethylarsonic acid (MMA V ), monomethylarsonous acid (MMA III ), monomethylmonothioarsonic acid (MMMTA V ), and dimethylmonothioarsinic acid (DMMTA V ) were also detected in both hair and nail samples. This is the first report of the detection of MMA III and MMMTA V as metabolites of arsenic in hair and nails of APL patients. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of 60Co radiation-induced grafting of methyl methacrylate on mechanical properties of bamboo

International Nuclear Information System (INIS)

Zhang Hao; Zhou Liang; Liu Shengquan; Qian Liangcun; Fei Benhua; Jiang Zehui

2011-01-01

In order to investigate the effect of radiation grafting on mechanical properties of bamboo, the original and carbonized bamboo soaked with monomer MMA were radiation grafted by 60 Co γ rays with the doses of 60-220 kGy. The results showed that compared with original blanks, treated with MMA and irradiated with the dose of 180 kGy the specific gravity, bending strength modulus of elasticity of original bamboo increased by 6.7%, 4.4%, and 28%, meanwhile its oven-dried radial, tangential and volumetric shrinkage decreased by 38.9%, 47.4%, and 32.9%, respectively. What is more, treated with MMA and irradiated with the doses of 140 kGy the specific gravity and modulus of elasticity of carbonized bamboo increased by 6.8% and 20%, while its oven-dried radial, tangential, volumetric shrinkage decreased by 11%, 4.6% and 12%, respectively. The study reveals that mechanical properties of original and carbonized bamboo can be enhanced by radiation grafting copolymerization with suitable absorbed doses, which may be valuable for the further research of developing new bamboo plastic composites. (authors)

Effect of PGD2 on middle meningeal artery and mRNA expression profile of L-PGD2 synthase and DP receptors in trigeminovascular system and other pain processing structures in rat brain

DEFF Research Database (Denmark)

Sekeroglu, Aysegül; Jacobsen, Julie Mie; Jansen-Olesen, Inger

2017-01-01

Background Prostaglandins (PGs), particularly prostaglandin D2 (PGD2), E2 (PGE2), and I2 (PGI2), are considered to play a role in migraine pain. In humans, infusion of PGD2 causes lesser headache as compared to infusion of PGE2 and PGI2. Follow-up studies in rats have shown that infusion of PGE2...... and PGI2 dilate the middle meningeal artery (MMA), and mRNA for PGE2 and PGI2 receptors is present in rat trigeminovascular system (TVS) and in the brain structures associated with pain. In the present study, we have characterized the dilatory effect of PGD2 on rat MMA and studied the relative m...... tested tissues. DP1 receptor mRNA was expressed maximally in trigeminal ganglion (TG) and in cervical dorsal root ganglion (DRG). Conclusions High expression of DP1 mRNA in the TG and DRG suggest that PGD2 might play a role in migraine pathophysiology. Activation of the DP1 receptor in MMA was mainly...

Medicare Modernization Act (MMA) IRS Medicare Part D

Data.gov (United States)

Social Security Administration — SSA uses the Internal Revenue Service (IRS) information in determing the eligibility of Medicare recipients to receive subsidy payments for Medicare premiums. SSA...

Mixed martial arts induces significant fatigue and muscle damage up to 24 hours post-combat.

Science.gov (United States)

Ghoul, Nihel; Tabben, Montassar; Miarka, Bianca; Tourny, Claire; Chamari, Karim; Coquart, Jeremy

2017-06-22

This study investigates the physiological/physical responses to a simulated mixed martial arts (MMA) competition over 24 hr. Twelve fighters performed a simulated MMA competition, consisting of three 5-min MMA matches. Physiological/physical data were assessed before (Trest), directly after round 1 (Trd1), round 2 (Trd2) and round 3 (Trd3), and then 30-min (Trecovery30min) and/or 24-hr (Trecovery24h) post-competition. Heart rate (HR), rating of perceived exertion (RPE) and blood lactate concentration ([La]) were assessed at Trest, Trd1, Trd2 and Trd3. Biological data were collected at Trest, Trd3, Trecovery30min and Trecovery24h. Physical tests were performed at Trest, Trecovery30min and Trecovery24h. HR, RPE and [La] were high during competition. Leukocytes, hemoglobin, total protein and glycemia were increased at Trd3 compared with all other time points (p<0.05). Cortisol was increased at Trd3 compared with Trest and Trecovery24h (p<0.05). Testosterone was higher at Trd3 and Trecovery30min than Trest (p<0.001). Higher values of uric acid were noted during recovery periods (p<0.001). Lactate dehydrogenase was lower at Trest compared with Trd3, Trecovery30min and Trecovery24h (p<0.05). Countermovement jump was higher at Trest than Trecovery30min (p=0.020). Consequently, MMA is a high-intensity intermittent combat sport that induces significant fatigue and muscle damage, both of which are still present 24-hr post-competition.

Urinary arsenic profile affects the risk of urothelial carcinoma even at low arsenic exposure

International Nuclear Information System (INIS)

Pu, Y.-S.; Yang, S.-M.; Huang, Y.-K.; Chung, C.-J.; Huang, Steven K.; Chiu, Allen Wen-Hsiang; Yang, M.-H.; Chen, C.-J.; Hsueh, Y.-M.

2007-01-01

Arsenic exposure is associated with an increased risk of urothelial carcinoma (UC). To explore the association between individual risk and urinary arsenic profile in subjects without evident exposure, 177 UC cases and 313 age-matched controls were recruited between September 2002 and May 2004 for a case-control study. Urinary arsenic species including the following three categories, inorganic arsenic (As III + As V ), monomethylarsonic acid (MMA V ) and dimethylarsinic acid (DMA V ), were determined with high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Arsenic methylation profile was assessed by percentages of various arsenic species in the sum of the three categories measured. The primary methylation index (PMI) was defined as the ratio between MMA V and inorganic arsenic. Secondary methylation index (SMI) was determined as the ratio between DMA V and MMA V . Smoking is associated with a significant risk of UC in a dose-dependent manner. After multivariate adjustment, UC cases had a significantly higher sum of all the urinary species measured, higher percent MMA V , lower percent DMA V , higher PMI and lower SMI values compared with controls. Smoking interacts with the urinary arsenic profile in modifying the UC risk. Differential carcinogenic effects of the urinary arsenic profile, however, were seen more prominently in non-smokers than in smokers, suggesting that smoking is not the only major environmental source of arsenic contamination since the UC risk differs in non-smokers. Subjects who have an unfavorable urinary arsenic profile have an increased UC risk even at low exposure levels

Effect of the Z- and Macro-R-Group on the Thermal Desulfurization of Polymers Synthesized with Acid/Base "Switchable" Dithiocarbamate RAFT Agents.

Science.gov (United States)

Stace, Sarah J; Fellows, Christopher M; Moad, Graeme; Keddie, Daniel J

2018-05-11

Thermolysis is examined as a method for complete desulfurization of reversible addition-fragmentation chain transfer (RAFT)-synthesized polymers prepared with acid/base "switchable" N-methyl-N-pyridyldithiocarbamates [RS 2 CZ or RS 2 CZH + ]. Macro-RAFT agents from more activated monomers (MAMs) (i.e., styrene (St), N-isopropylacrylamide (NIPAm), and methyl methacrylate (MMA)) with RS 2 CZH + and less activated monomers (LAMs) (i.e., vinyl acetate (VAc) and N-vinylpyrolidone (NVP)) with RS 2 CZ are prepared by RAFT polymerization and analyzed by thermogravimetric analysis. In all cases, a mass loss consistent with loss of the end group (ZCS 2 H) is observed at temperatures lower than, and largely discrete from, that required for further degradation of the polymer. The temperatures for end group loss and the new end groups formed are strongly dependent on the identity of the R(P) n and the state of the pyridyl Z group; increasing in the series poly(MMA) < poly(St) ∼ poly(NIPAm) < poly(VAc) ∼ poly(NVP) for S 2 CZ and poly(MMA) < poly(St) ∼ poly(NIPAm) for S 2 CZH + . Clean end group removal is possible for poly(St) and poly(NVP). For poly(NIPAm), the thiocarbonyl chain end is removed, but the end group identity is less certain. For poly(MMA) and poly(VAc), some degradation of the polymer accompanies end group loss under the conditions used and further refinement of the process is required. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The use of unsaturated zone solutes and deuterium profiles in the study of groundwater recharge in the semi-arid zone of Nigeria

International Nuclear Information System (INIS)

Goni, I.B.; Edmunds, W.M.

2001-01-01

Two unsaturated zone profiles (MF and MG) in NE Nigeria have been sampled for inert tracers (Cl, Br, NO 3 and δ 2 H to investigate recharge rates and processes. The upper MF and MG profiles have sandy lithology, lower moisture content ( 2 H around -30 per mille. All these indicate that present day recharge is taking place. The lower section of the MF profile shows a distinct contrast with high moisture content (up to 27%), very high chloride (average 2892 mg/L) and relatively enriched deuterium (-12 per mille), indicating the effect of evaporative enrichment. This lower section corresponds to low permeability lacustrine deposits probably representing the former bed of Lake Chad where little or no infiltration has been occurring since the mid-Holocene when the lake extended over this area. The sand-covered areas of the Sahel of the NE Nigeria provide an important phreatic aquifer. An estimation of the amount of recharge using the unsaturated zone chloride mass balance gives significant rates of 14 mm/a and 22 mm/a for the upper MF and MG profiles respectively. These rates mainly span the period of the recent Sahel drought and even higher recharge rates may occur during wetter periods. These rates fall within the 14 mm/a to 53 mm/a range estimated for the Manga Grasslands area in the NE Nigeria obtained in an earlier study. From the water resource point of view, the region has potential for perennially-recharged groundwater resources that can sustain the present abstraction level which is mainly via dug wells. (author)

Precipitation Polymerization of Methyl Methacrylate by AGET ATRP%MMA的电子活化再生原子转移自由基沉淀聚合

Institute of Scientific and Technical Information of China (English)

张守成; 陈永平

2013-01-01

Precipitation polymerization of methyl methacrylate (MMA) by AGET ATRP, with cuprous chloride (CuCl2 · 2H2O)/ascorbic acid/PMDETA(C9 H23 N3) as catalyst, and initiated by ethyl bromoacetate in ethanol solution, was carried out. Molecular weight and molecular weight distribution were characterized by GPC. The results show that MMA can be rapidly polymerized with high monomer conversioa PMMA with relative narrow molecular weight distribution can be synthesized. Precipitation polymerization of methyl methacrylate (MMA) by AGET ATRP possesses characteristics of controlled/" living" radical polymerization.%以乙醇为溶剂,氯化铜(CuCl2·2H2O)为催化剂,抗坏血酸为还原剂,溴乙酸乙酯为引发剂,PMDETA为配体,进行了甲基丙烯酸甲酯(MMA)的电子活化再生原子转移自由基(AGET ATRP)沉淀聚合,通过GPC和称重法对聚合物进行表征.结果表明,在这种催化体系中甲基丙烯酸甲酯的转化速率较快,甲基丙烯酸甲酯的AGETATRP沉淀聚合得到了较好的实现,获得了分子量分布较窄的聚合物,并且沉淀聚合实现了产物与催化剂的分离.

微乳液聚合法制备放射源%Preparation of Radioactive Source by Polymerization of Microemulsions

Institute of Scientific and Technical Information of China (English)

卢金辉; 李忠勇

2015-01-01

采用微乳液聚合方法制备放射源。选择甲基丙烯酸甲酯(MMA)/甲基丙烯酸羟乙酯(HEMA)/水(H 2 O)为微乳液体系,利用滴定法绘制三元相图,研究了温度与促进剂 N,N-二甲基对甲苯胺(DMT)对聚合的影响,利用 MMA(DMT)/HEMA/H 2 O 反向无皂微乳液聚合制备了99 Mo 和125 I 线源,并测定了放射源活度分布均匀性。结果表明,微乳液聚合是一种制备放射源的良好方法。%A new method for preparation of radioactive source by polymerization of microemulsions was introduced.Methyl methacrylate (MMA)/hydroxyethyl methylac-rylate (HEMA)/water (H 2 O)was selected as the microemulsions system.The ternary phase diagram was figured out by the conventional titration technique,and the influ-ences of temperature and N,N-dimethyl toluidine (DMT)as the accelerator on the polymerization were investigated.Then,line sources of 9 9 Mo and 1 2 5 I were obtained by polymerization of MMA (DMT)/HEMA/H 2 O soap-free inverse microemulsions,and the radioactivity distribution was measured.The results showed that preparation of radioactive source by polymerization of microemulsions was a good method.

Weight Loss Strategies in Combat Sports and Concerning Habits in Mixed Martial Arts.

Science.gov (United States)

Barley, Oliver R; Chapman, Dale W; Abbiss, Chris R

2017-12-28

Combat sports are typically divided into weight classes and body mass manipulation to reach a weight class is commonplace. Previous research suggests that mixed martial arts (MMA) weight loss practices may be more extreme than other combat sports. We sought to investigate the magnitude of weight lost and prevalence of weight loss strategies in different combat sports. Competitors (n=637) from Brazilian jiu jitsu (BJJ), boxing, judo, MMA, muay Thai/kickboxing (MT/K), taekwondo (TKD) and wrestling completed an online questionnaire seeking information regarding their weight loss practices. Body mass manipulation was commonly undertaken by all combat sports athletes, with a particularly high incidence of gradual dieting, increased exercise and fluid restriction. Skipping meals was higher in TKD and wrestling (84%) compared with the other combat sports (~58%), whilst training in heated rooms and forced oral fluid loss (spitting) was higher in wrestling (83% and 47%, respectively) compared with other combat sports (~45% and ~19%, respectively). MMA athletes reported the highest usage of sauna (76%) and water loading (67%) whilst also reporting the second highest use of training in rubber/plastic suits (63%). Body mass manipulation was present in all combat sports with the prevalence and magnitude of acute weight loss greater in MMA. The incidence of and practices reported will assist support staff to be fully aware of the variety of methods these athletes and coaches may use to achieve weight loss. Additionally, the results could aid regulatory bodies in the further development of policies on weight cutting.

Modulated microwave absorption spectra from Josephson junctions on a scratched niobium wire

International Nuclear Information System (INIS)

Rubins, R.S.; Hutton, S.L.; Ravindran, K.; Subbaraman, K.; Drumheller, J.E.

1997-01-01

Modulated microwave absorption (MMA) spectra from Josephson junction formations on a scratched Nb wire have been studied at 9.3 GHz and 4 K. The peak-to-peak separation, δH of the Josephson lines was found to vary linearly with P 1/2 , where P is the applied microwave power, in contrast to a recent interpretation of junction formation in pressed lead pieces by Rubins, Drumheller, and Trybula. The interpretation of the MMA data on Nb are given in terms of the theory of Vichery, Beuneu, and Lejay for superconducting loops containing weak links. copyright 1997 The American Physical Society

STABILITY OF EMULSIFIER-FREE EMULSION COPOLYMERIZATION OF METHYL METHACRYLATE/ BUTYL ACRYLATE/SODIUM MONO(ETHYL POLYOXYETHYLENE) MALEATE

Institute of Scientific and Technical Information of China (English)

Mao-gen Zhang; Zhi-xue Weng; Zhi-ming Huang; Zu-ren Pan

1999-01-01

A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.

Controlled Grafting of Poly(methyl methacrylate) Brushes on Poly(vinylidene fluoride) Powders by Surface-initiated Atom Transfer Radical Polymerization

Institute of Scientific and Technical Information of China (English)

TANG Zhaoqi; LI Wei; LIU Lanqin; HUANG Lei; ZHOU Jin; YU Haiyin

2009-01-01

Controlled grafting of well-defined polymer brushes of methyl methacrylate (MMA) on the poly(vinylidene fluoride) (PVDF) powders was carded out by the surface-initiated atom transfer radical polymerization (ATRP). The ATRP initiator was anchored on the PVDF surface by alkaline treatment, followed by UV-induced bromination; then methyl methacrylate (MMA) was grafted onto the brominated PVDF by the ATRP technique. The chemical composition changes of PVDF were characterized by Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). FT-IR and XPS results clearly indicated the successful graft of poly(methyl methacrylate) onto the PVDF surface.

SYNTHESIS OF STYRENE-METHYL METHACRYLATE BLOCK COPOLYMER BY POLYAZOAMIDE AS INITIATOR

Institute of Scientific and Technical Information of China (English)

WANG Zhongyi; WEI Jeqing

1996-01-01

Polyazoamide(PAA) was used as initiator to prepare block copolymer P(MMA-b-St) by free radical polymerization. The fraction of block copolymer was about 50%. The structure of the block-copolymer was characterized by IR and the results of 1H-NMR and GPC showed that the content of the block and the molecular weight (-Mw) of the prepolymer and block copolymer could be controlled by varying the mol ratio of styrene/PAA and MMA/prepolymer. DSC and TEM results revealed that the block copolymer has two separated glass transition temperatures and phase separation within the domain structure.

EFFECTS OF ω-ACRYLOYL POLY(ETHYLENE OXIDE) MACROMONOMER ON EMULSIFIER-FREE EMULSION COPOLYMERIZATION OF METHYL METHACRYLATE AND n-BUTYL ACRYLATE

Institute of Scientific and Technical Information of China (English)

无

1998-01-01

Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macromonomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxide with diphenyl methyl potassium as the initiator and acryloyl chloride as the reaction terminating agent. The polymer was characterized by FTIR and SEC. The emulsifier-free emulsion polymerization of methyl methacrylate (MMA) and n-butyl acrylate (BA) containing various concentrations of PEO-A was studied. In all cases stable emulsion coplymerizations of MMA and BA were obtained. The stabilizing effect was found to be dependent on the molecular weight and the feed amount of the macromonomer.

Être Normaliens et pratiquants de Mixed Martial Arts

OpenAIRE

Quidu, Matthieu; Delalandre, Matthieu

2018-01-01

La rencontre est a priori improbable entre d’une part le Mixed Martial Arts (MMA), cette discipline de combat sulfureuse et, d’autre part, les élèves de l’École normale supérieure de Lyon, aux parcours académiques d’excellence. Après avoir déconstruit l’illusion d’une dissonance culturelle en termes de légitimité, nous identifions les significations effectives que les Normaliens investissent dans leur pratique. Celles-ci s’avèrent en grande partie génériques et non spécifiques au MMA (dévelop...

Influence of wood extractives in the polymerization of methyl methacrylate by gamma irradiation

International Nuclear Information System (INIS)

Burillo de V, G.; Loyola V, V.M.; Albarran S, G.; Candelas, J.

1975-01-01

Those materials that can be extracted from pine or oak by ether, ethanol, methyl methacrylate (MMA), or benzene--alcohol all act as inhibitors in the γ polymerization of MMA--wood composites. It was found that preirradiation of either the wood or of the wood--monomer combination reduces or eliminates the inhibitory effect. The most practical industrial solution to this problem is to increase the dose, thereby achieving high molecular polymer in the composite. However, the presence of a maximum in the molecular weight--dose curves means that each wood--monomer pair may have a different optimum dose

Hållbarhetsredovisning : Identifiering och prioritering av hållbarhetsfrågor i en verksamhet som Sweco Environment

OpenAIRE

Söderström, Anna-Karin

2017-01-01

I en hållbarhetsredovisning redovisar en organisation information om sin påverkan inom ekonomisk, miljömässig och social hållbar utveckling. Några av de inledande stegen i en redovisningsprocess är att identifiera organisationens hållbarhetsfrågor, och att bestämma frågornas prioriteringsordning för att på så sätt kunna bestämma ett väsentligt innehåll till redovisningen. De här stegen av redovisningsprocessen har varit i fokus under arbetet. En identifiering och prioritering av konsultbolage...

Identification of hepatic biomarkers for physiological imbalance of dairy cows in early and mid lactation using proteomic technology

DEFF Research Database (Denmark)

Moyes, Kasey; Bendixen, Emøke; Codrea, Marius Cosmin

2013-01-01

the ration with 60% wheat straw. Liver biopsies were collected −1 and 3 d relative to restriction. Before restriction, an index for PI was calculated based on plasma nonesterified fatty acids, β-hydroxybutyrate, and glucose concentrations. Within E and M cows, a subsets of 6 cow was classified as having...... as potential hepatic biomarkers for PI for cows during early lactation and alcohol dehydrogenase-4 and methylmalonate-semialdehyde dehydrogenase for cows in mid lactation. This preliminary study identified new biomarkers in liver for PI and provided a better understanding of the differences in coping...

Erosion rates and landscape evolution of the lowlands of the Upper Paraguay river basin (Brazil) from cosmogenic 10Be

Science.gov (United States)

Pupim, Fabiano do Nascimento; Bierman, Paul R.; Assine, Mario Luis; Rood, Dylan H.; Silva, Aguinaldo; Merino, Eder Renato

2015-04-01

The importance of Earth's low sloping areas in regard to global erosion and sediment fluxes has been widely and vigorously debated. It is a crucial area of research to elucidate geologically meaningful rates of land-surface change and thus the speed of element cycling on Earth. However, there are large portions of Earth where erosion rates have not been well or extensively measured, for example, the tropical lowlands. The Cuiabana lowlands are an extensive low-altitude and low-relief dissected metamorphic terrain situated in the Upper Paraguay river basin, central-west Brazil. Besides exposures of highly variable dissected metamorphic rocks, flat residual lateritic caps related to a Late Cenozoic planation surface dominate interfluves of the Cuiabana lowlands. The timescale over which the lowlands evolved and the planation surface developed, and the rate at which they have been modified by erosion, are poorly known. Here, we present measurements of in situ produced cosmogenic 10Be in outcropping metamorphic bedrock and clastic-lateritic caps to quantify rates of erosion of the surface and associated landforms in order to better understand the Quaternary landscape evolution of these lowlands. Overall, slow erosion rates (mean 10 m/Ma) suggest a stable tectonic environment in these lowlands. Erosion rates vary widely between different lithologies (range 0.57 to 28.3 m/Ma) consistent with differential erosion driving regional landform evolution. The lowest erosion rates are associated with the low-relief area (irregular plains), where clastic-laterite (mean 0.67 m/Ma) and quartzite (mean 2.6 m/Ma) crop out, whereas the highest erosion rates are associated with dissection of residual hills, dominated by metasandstone (mean 11.6 m/Ma) and phyllite (mean 27.6 m/Ma). These data imply that the Cuiabana lowland is comprised of two dominant landform sets with distinct and different dynamics. Because the planation surface (mostly lowlands) is lowering and losing mass more

Clinical neurogenetics: neurologic presentations of metabolic disorders.

Science.gov (United States)

Kwon, Jennifer M; D'Aco, Kristin E

2013-11-01

This article reviews aspects of the neurologic presentations of selected treatable inborn errors of metabolism within the category of small molecule disorders caused by defects in pathways of intermediary metabolism. Disorders that are particularly likely to be seen by neurologists include those associated with defects in amino acid metabolism (organic acidemias, aminoacidopathies, urea cycle defects). Other disorders of small molecule metabolism are discussed as additional examples in which early treatments have the potential for better outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

Anesthetic Management of A Parturient With Diabetic Keto-Acidosis

OpenAIRE

Rupasinghe M N; Hemmad A R

2013-01-01

Diabetic ketoacidosis (DKA) in pregnancy is a life threatening medical emergency. It can compromise both the fetus and the mother profoundly. The incidence of DKA during pregnancy ranges between 2 to 3%, and carries a 10–20% risk of fetal death.1 DKA is characterized by a biochemical triad of ketonemia, hyperglycemia and acidemia. We present a case of a parturient with mismanaged DKA that was brought to the operating room for a STAT cesarean section (C/S) due to fetal distress and discuss the...

Effects of nitrogen and strain age embrittlement on toughness of MMA welds. A final report on the joint reserach project - GKSS Research Centre, Geesthacht, Germany, and Oerlikon Welding Ltd., Zurich, Switzerland

Energy Technology Data Exchange (ETDEWEB)

Kocak, M. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Materialforschung; Achar, D.R.G.; Evans, G.M. [OERLIKON Welding Ltd., Zurich (Switzerland)

1998-12-31

A detailed literature review has been carried out on the topic to identify the areas requiring further investigations. Based on this investigations have been carried out to evaluate the influence of dissolved nitrogen in weld metals on their toughness and strain aging behaviour through fracture mechanics as well as conventional impact testing approaches. MMA C-Mn steel weld metals bearing nitrogen between 80 to 210 ppm were investigated under four different post-weld conditions, namely: 1. as welded, 2. stress relieved, 3. artificially strain aged and 4. artificially strain aged and stress relieved. Quantitative metallography and low load microhardness studies of microphases were integral part of these investigations. The results demonstrate the highly detrimental effect of nitrogen on the toughness behaviour of C-Mn steel weld metal particularly under strain aging conditions. This is substantiated through decrease of acicular ferrite with the accompanying increase in primary ferrite and ferrite with second phases in the microstructures. Also, there is a distinctive increase in acicular ferrite microhardness. Post-weld stress relieving heat treatment under these conditions effects only marginal improvement in toughness and shifts the fracture behaviour from brittle to ductile or quasi-ductile only in the case of low nitrogen weld metals. Comparing the results of the CTOD and Charpy tests, it is observed that both methods measure the influence of nitrogen on toughness behaviour in the same trend but the magnitudes of the effect measured are different whereby the fracture mechanics method appears very conservative. (orig.) [Deutsch] Untersucht werden der Einfluss von Stickstoff im Bereich von 80-120 ppm auf die Zaehigkeit und Reckalterungsversproedungs-Verhaeltnisse des C-Mn-Strahlschweissgutes. Die Pruefungen erfolgen mit technologischen Kerbschlagbiege- und CTOD-Versuchen an Schweissguetern, die durch mehrlagiges Lichtbogenschweissen hergestellt wurden, unter vier

Inductively coupled plasma mass spectrometry study of the retention behavior of arsenic species on various solid phase extraction cartridges and its application in arsenic speciation

Energy Technology Data Exchange (ETDEWEB)

Yu Chunhai; Cai Qiantao E-mail: qtcai@cawt.sui.com.sg; Guo Zhongxian; Yang Zhaoguang; Khoo, Soo Beng

2003-07-18

Inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate the retention behavior of arsenite, arsenate, monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AsB), arsenocholine (AsC), trimethylarsine oxide (TMAO) and tetramethylarsonium ion (TMAI) on various silica-based solid phase extraction (SPE) cartridges. A method for arsenic speciation is then developed on the basis of selective SPE separation of arsenic species and highly sensitive ICP-MS detection. Factors affecting the retention and elution of arsenic species were examined. Results showed that the retention of arsenic species depended on the chemical characteristics of arsenic species and the types of sorbent materials. Change of pH in the range of 2.0-9.0 did not show significant effects on the retention of DMA, AsB, AsC, TMAI and TMAO on an ethylbenzene sulfonic acid-based strong cation exchange (SCX-3) cartridge. pH also did not influence the retention of AsB, AsC, TMAI and TMAO on a mixed-mode (M-M) cartridge containing non-polar, strong cation exchange and strong anion exchange (SAX) functional groups. However, the retentions of As(V) and MMA on the SAX and the M-M cartridge changed with pH. As(V) and MMA were completely retained on the SAX cartridge and sequentially selectively eluted with 1.0 mol l{sup -1} acetic acid (for MMA). DMA, AsB, AsC, TMAI and TMAO were completely retained on the SCX-3 cartridge and sequentially selectively eluted with 1.0 mol l{sup -1} HNO{sub 3} (for DMA). As(V), MMA, AsB, AsC, TMAI and TMAO were completely retained on the M-M cartridge. As(III) was not retained on either cartridge and remained in solution. Arsenic species in solution and those eluted from the cartridges were subsequently determined by ICP-MS. A detection limit of 8 ng l{sup -1} arsenic in water sample was obtained. This method was successfully applied to arsenic speciation in various sources of water samples (drinking water, waste water, raw water, etc.) and US

Time-Motion and Biological Responses in Simulated Mixed Martial Arts Sparring Matches.

Science.gov (United States)

Coswig, Victor S; Ramos, Solange de P; Del Vecchio, Fabrício B

2016-08-01

Coswig, VS, Ramos, SdP, and Del Vecchio, FB. Time-motion and biological responses in simulated mixed martial arts sparring matches. J Strength Cond Res 30(8): 2156-2163, 2016-Simulated matches are a relevant component of training for mixed martial arts (MMA) athletes. This study aimed to characterize time-motion responses and investigate physiological stress and neuromuscular changes related to MMA sparring matches. Thirteen athletes with an average age of 25 ± 5 years, body mass of 81.3 ± 9.5 kg, height of 176.2 ± 5.5 cm, and time of practice in MMA of 39 ± 25 months participated in the study. The fighters executed three 5-minute rounds with 1-minute intervals. Blood and salivary samples were collected and physical tests and psychometric questionnaires administered at 3 time points: before (PRE), immediately after (POST), and 48 hours after the combat (48 h). Statistical analysis applied analysis of variance for repeated measurements. In biochemical analysis, significant changes (p ≤ 0.05) were identified between PRE and POST (glucose: 80.3 ± 12.7 to 156.5 ± 19.1 mg·ml; lactate: 4 ± 1.7 to 15.6 ± 4.8 mmol·dl), POST and 48 hours (glucose: 156.5 ± 19.1 to 87.6 ± 15.5 mg·ml; lactate: 15.6 ± 4.8 to 2.9 ± 3.5 mmol·dl; urea: 44.1 ± 8.9 to 36.3 ± 7.8 mg·ml), and PRE and 48 hours (creatine kinase [CK]: 255.8 ± 137.4 to 395.9 ± 188.7 U/L). In addition, time-motion analyses showed a total high:low intensity of 1:2 and an effort:pause ratio of 1:3. In conclusion, simulated MMA sparring matches feature moderate to high intensity and a low degree of musculoskeletal damage, which can be seen by absence of physical performance and decrease in CK. Results of the study indicate that sparring training could be introduced into competitive microcycles to improve technical and tactical aspects of MMA matches, due to the high motor specificity and low muscle damage.