CT and MRI imaging of the brain in MELAS syndrome.

Science.gov (United States)

Pauli, Wojciech; Zarzycki, Artur; Krzyształowski, Adam; Walecka, Anna

2013-07-01

MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, stroke-like episodes) is a rare, multisystem disorder which belongs to a group of mitochondrial metabolic diseases. As other diseases in this group, it is inherited in the maternal line. In this report, we discussed a case of a 10-year-old girl with clinical and radiological picture of MELAS syndrome. We would like to describe characteristic radiological features of MELAS syndrome in CT, MRI and MR spectroscopy of the brain and differential diagnosis. The rarity of this disorder and the complexity of its clinical presentation make MELAS patients among the most difficult to diagnose. Brain imaging studies require a wide differential diagnosis, primarily to distinguish between MELAS and ischemic stroke. Particularly helpful are the MRI and MR spectroscopy techniques.

CT and MRI imaging of the brain in MELAS syndrome

International Nuclear Information System (INIS)

Pauli, Wojciech; Zarzycki, Artur; Krzyształowski, Adam; Walecka, Anna

2013-01-01

MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, stroke-like episodes) is a rare, multisystem disorder which belongs to a group of mitochondrial metabolic diseases. As other diseases in this group, it is inherited in the maternal line. In this report, we discussed a case of a 10-year-old girl with clinical and radiological picture of MELAS syndrome. We would like to describe characteristic radiological features of MELAS syndrome in CT, MRI and MR spectroscopy of the brain and differential diagnosis. The rarity of this disorder and the complexity of its clinical presentation make MELAS patients among the most difficult to diagnose. Brain imaging studies require a wide differential diagnosis, primarily to distinguish between MELAS and ischemic stroke. Particularly helpful are the MRI and MR spectroscopy techniques

76 FR 75524 - Marine Mammals

Science.gov (United States)

2011-12-02

..., 263 13th Avenue South, Saint Petersburg, Florida 33701; phone (727) 824-5312; fax (727) 824-5309. FOR... (Globicephala melas), although other small cetacean species may also be studied. The locations for the field... of 1969 (42 U.S.C. 4321 et seq.), an initial determination has been made that the activity proposed...

75 FR 29991 - Marine Mammals; receipt of application for permit amendment

Science.gov (United States)

2010-05-28

...; phone (978)281-9300; fax (978)281-9333; and Southeast Region, NMFS, 263 13th Avenue South, Saint... delphinids such as long-finned pilot whales (Globicephala melas), although other small cetacean species may... expiration date of the permit. In compliance with the National Environmental Policy Act of 1969 (42 U.S.C...

MELAS syndrome

International Nuclear Information System (INIS)

Bruehl, K.; Kraemer, G.; Bornemann, A.

1988-01-01

This is a case report on a patient with MELAS (mitochondrial myopathy, encephalopathy, lactic acidoses and stroke/like episodes). This study documents, by CT scan, the progression of the disease for 7 years. The first CT scan was normal; all subsequent CT scans were pathological. In addition, one MRI study was done. (orig.) [de

Adrenal insufficiency in a child with MELAS syndrome.

Science.gov (United States)

Afroze, Bushra; Amjad, Nida; Ibrahim, Shahnaz H; Humayun, Khadija Nuzhat; Yakob, Yusnita

2014-11-01

Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) are established subgroups of mitochondrial encephalomyopathy. m.3243A>G a common point mutation is detected in tRNA in majority of patients with MELAS phenotype whereas m.8344A>G point mutation in tRNA is observed, in MERRF phenotype. Adrenal insufficiency has not been reported in mitochondrial disease, except in Kearns-Sayre Syndrome (KSS), which is a mitochondrial deletion syndrome. We report an unusual presentation in a five year old boy who presented with clinical phenotype of MELAS and was found to have m.8344A>G mutation in tRNA. Addison disease was identified due to hyperpigmentation of lips and gums present from early childhood. This is the first report describing adrenal insufficiency in a child with MELAS phenotype. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

MR OEF imaging in MELAS.

Science.gov (United States)

Xie, Sheng

2014-01-01

Oxygen extraction fraction (OEF) is defined as the ratio of blood oxygen that a tissue takes from the blood flow to maintain function and morphological integrity. OEF reflects the efficiency of oxygen utilization by the tissue and, therefore, is a hemodynamic measure in brain ischemia. Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a common mitochondrial disorder. It is characterized by neurological remissions and relapses and associated with progressive neurocognitive deficits. Because of abnormalities of mitochondrial function in MELAS, defects in the oxidative metabolic pathways of energy production decrease the cerebral oxygen utilization and lead to the reduction of OEF. Quantification of OEF can reflect the functional status of cerebral mitochondria and provide insight into the pathophysiological changes in the brain in MELAS. In light of recent advances in MRI, the discovery of the blood-oxygen level-dependent signal has allowed development of MRI methods targeted toward quantitative OEF imaging. A new MR sequence, termed the gradient-echo sampling of spin echo, was successfully developed to enable quantitative assessment of the OEF in the brain tissue. MR OEF imaging in patients with MELAS detects extensive OEF reduction in the stroke-like lesions, as well as in the normal-appearing brain regions. More severe dysfunction of the mitochondria in the stroke-like lesions was implied at the onset of the stroke-like episode. Determination of OEF throughout the episode demonstrated a chronological change in mitochondrial function in individual cases. Such neuroimaging findings might provide some clues in the investigation of the underlying mechanisms of stroke-like episodes.

[Psychiatric disturbances in five patients with MELAS syndrome].

Science.gov (United States)

Magner, Martin; Honzik, Tomas; Tesarova, Marketa; Dvorakova, Veronika; Hansiková, Hana; Raboch, Jiři; Zeman, Jiři

2014-01-01

Mitochondrial disorders of energetic metabolism (MD) represent a heterogeneous group of diseases manifesting at any age with a broad spectrum of clinical symptoms, including psychiatric disorders. The aim of the study was to characterize psychiatric symptoms and diagnoses in five patients with MELAS syndrome between the ages of 17 and 53 years. Four of MELAS patients them harbored the prevalent mitochondrial DNA (mtDNA) mutation 3243A>G, and one patient had the mtDNA mutation 12706T>C. Three patients had positive family histories for MELAS syndrome. In one patient, depression was diagnosedas the first symptom ofMELAS syndrome. Depression also preceded a stroke-like episode in one patient. Four patients had disturbed cognitive functions, confusional states occurred in three patients. One patient manifested psychotic (schizophrenia-like) symptoms. Mitochondrial disorders deserve consideration as part of the differential diagnosis, especially, if there is suspected involvement of other organ groups or positive family history of MD.

MELAS syndrome in a child: CT and MR findings

International Nuclear Information System (INIS)

Choi, Bye Young; Hong, Soo Jong; Cho, Jeong Hee; Suh, Dae Chul; Hong, Chang Yee

1993-01-01

MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) is one of the mitochondrial encephalomyopathy, A rare disease caused by a disturbance of the mitochondrial chain of respiration. MELAS is confirmed by typical light and electron microscopic findings: 'ragged red fibers' by modified Gomori trichrome stain on light microscope and numerous abnormal mitochondria on electron microscope. We experienced a boy with the characteristic clinical and pathologic findings of MELAS. Our patient demonstrated bilateral basal ganglia calcifications and infarction at right parieto-occipital and thalamic areas on CT and MR. We found that MRI was more sensitive and represented the infarcted lesions better than CT. Detection of cerebral insults of MELAS by MRI is important in making decision on patient treatment and also in prediction of the patient prognosis

Cortical venous disease severity in MELAS syndrome correlates with brain lesion development.

Science.gov (United States)

Whitehead, M T; Wien, M; Lee, B; Bass, N; Gropman, A

2017-08-01

MELAS syndrome is a mitochondrial disorder typified by recurrent stroke-like episodes, seizures, and progressive brain injury. Abnormal mitochondria have been found in arterial walls implicating a vasculogenic etiology. We have observed abnormal cortical vein T2/FLAIR signal in MELAS patients, potentially representing wall thickening and sluggish flow. We sought to examine the relationship of hyperintense veins and brain lesions in MELAS. Imaging databases at two children's hospitals were searched for brain MRIs from MELAS patients. Artifact, sedated exams, and lack of 2D-T2/FLAIR sequences were exclusion criteria. Each exam was assigned a venous score based on number of T2/FLAIR hyperintense veins: 1 = 20. Cumulative brain lesions and venous score in MELAS and aged-matched normal exams were compared by Mann-Whitney test. A total of 106 exams from 14 unique MELAS patients (mean 16 ± 3 years) and 30 exams from normal aged-matched patients (mean 15 ± 3 years) were evaluated. Median venous score between MELAS and control patients significantly differed (3 versus 1; p MELAS group, venous score correlated with presence (median = 3) or absence (median = 1) of cumulative brain lesions. In all 8 MELAS patients who developed lesions, venous hyperintensity was present prior to, during, and after lesion onset. Venous score did not correlate with brain lesion acuity. Abnormal venous signal correlates with cumulative brain lesion severity in MELAS syndrome. Cortical venous stenosis, congestion, and venous ischemia may be mechanisms of brain injury. Identification of cortical venous pathology may aid in diagnosis and could be predictive of lesion development.

Magnetic resonance imaging in MELAS syndrome

International Nuclear Information System (INIS)

Rosen, L.; Phillips, S.; Enzmann, D.

1990-01-01

MELAS syndrome is a distinct clinical entity belonging to a group of mitochondrial encephalomyopathies characterized by the tetrad of myopathy, encephalopathy, lactic acidosis, and stroke-like episodes. Computed tomography (CT) and magnetic resonance (MR) findings are reviewed in a patient with MELAS. Serial CT studies demonstrated multiple 'migrating' infarcts in various stages of evolution involving primarily the posterior temporal and occipital regions. MR was more sensitive than CT in demonstrating the number and extent of cortical lesions in this disease entity. (orig.)

MELAS syndrome presenting as an acute surgical abdomen.

Science.gov (United States)

Dindyal, S; Mistry, K; Angamuthu, N; Smith, G; Hilton, D; Arumugam, P; Mathew, J

2014-01-01

MELAS (mitochondrial cytopathy, encephalomyopathy, lactic acidosis and stroke-like episodes) is a syndrome in which signs and symptoms of gastrointestinal disease are uncommon if not rare. We describe the case of a young woman who presented as an acute surgical emergency, diagnosed as toxic megacolon necessitating an emergency total colectomy. MELAS syndrome was suspected postoperatively owing to persistent lactic acidosis and neurological symptoms. The diagnosis was later confirmed with histological and genetic studies. This case highlights the difficulties in diagnosing MELAS because of its unpredictable presentation and clinical course. We therefore recommend a high index of suspicion in cases of an acute surgical abdomen with additional neurological features or raised lactate.

Serial diffusion-weighted imaging in MELAS

International Nuclear Information System (INIS)

Ohshita, T.; Oka, M.; Imon, Y.; Watanabe, C.; Katayama, S.; Yamaguchi, S.; Kajima, T.; Mimori, Y.; Nakamura, S.

2000-01-01

Clinical features of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) resemble those of cerebral infarcts, but the pathogenesis of infarct-like lesions is not fully understood. To characterise these infarct-like lesions, we studied two patients with MELAS using diffusion-weighted (DWI) MRI before and after stroke-like episodes and measured the apparent diffusion coefficient (ADC) in the new infarct-like lesions. These gave high signal on DWI and had much higher ADC than normal-appearing regions. The ADC remained high even 30 days after a stroke-like episode then decreased in lesions, with or without abnormality as shown by conventional MRI. We speculate that early elevation of ADC in the acute or subacute phase reflects vasogenic rather than cytotoxic edema. The ADC of the lesions, which disappeared almost completely with clinical improvement, returned to normal levels, which may reflect tissue recovery without severe damage. To our knowledge, this is the first study of DWI in MELAS. (orig.)

Genome-Wide Divergence in the West-African Malaria Vector Anopheles melas

Directory of Open Access Journals (Sweden)

Kevin C. Deitz

2016-09-01

Full Text Available Anopheles melas is a member of the recently diverged An. gambiae species complex, a model for speciation studies, and is a locally important malaria vector along the West-African coast where it breeds in brackish water. A recent population genetic study of An. melas revealed species-level genetic differentiation between three population clusters. An. melas West extends from The Gambia to the village of Tiko, Cameroon. The other mainland cluster, An. melas South, extends from the southern Cameroonian village of Ipono to Angola. Bioko Island, Equatorial Guinea An. melas populations are genetically isolated from mainland populations. To examine how genetic differentiation between these An. melas forms is distributed across their genomes, we conducted a genome-wide analysis of genetic differentiation and selection using whole genome sequencing data of pooled individuals (Pool-seq from a representative population of each cluster. The An. melas forms exhibit high levels of genetic differentiation throughout their genomes, including the presence of numerous fixed differences between clusters. Although the level of divergence between the clusters is on a par with that of other species within the An. gambiae complex, patterns of genome-wide divergence and diversity do not provide evidence for the presence of pre- and/or postmating isolating mechanisms in the form of speciation islands. These results are consistent with an allopatric divergence process with little or no introgression.

MELA: Modelling in Ecology with Location Attributes

Directory of Open Access Journals (Sweden)

Ludovica Luisa Vissat

2016-10-01

Full Text Available Ecology studies the interactions between individuals, species and the environment. The ability to predict the dynamics of ecological systems would support the design and monitoring of control strategies and would help to address pressing global environmental issues. It is also important to plan for efficient use of natural resources and maintenance of critical ecosystem services. The mathematical modelling of ecological systems often includes nontrivial specifications of processes that influence the birth, death, development and movement of individuals in the environment, that take into account both biotic and abiotic interactions. To assist in the specification of such models, we introduce MELA, a process algebra for Modelling in Ecology with Location Attributes. Process algebras allow the modeller to describe concurrent systems in a high-level language. A key feature of concurrent systems is that they are composed of agents that can progress simultaneously but also interact - a good match to ecological systems. MELA aims to provide ecologists with a straightforward yet flexible tool for modelling ecological systems, with particular emphasis on the description of space and the environment. Here we present four example MELA models, illustrating the different spatial arrangements which can be accommodated and demonstrating the use of MELA in epidemiological and predator-prey scenarios.

Mitochondria: role of citrulline and arginine supplementation in MELAS syndrome.

Science.gov (United States)

El-Hattab, Ayman W; Emrick, Lisa T; Chanprasert, Sirisak; Craigen, William J; Scaglia, Fernando

2014-03-01

Mitochondria are found in all nucleated human cells and generate most of the cellular energy. Mitochondrial disorders result from dysfunctional mitochondria that are unable to generate sufficient ATP to meet the energy needs of various organs. Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a frequent maternally inherited mitochondrial disorder. There is growing evidence that nitric oxide (NO) deficiency occurs in MELAS syndrome and results in impaired blood perfusion that contributes significantly to several complications including stroke-like episodes, myopathy, and lactic acidosis. Both arginine and citrulline act as NO precursors and their administration results in increased NO production and hence can potentially have therapeutic utility in MELAS syndrome. Citrulline raises NO production to a greater extent than arginine, therefore, citrulline may have a better therapeutic effect. Controlled studies assessing the effects of arginine or citrulline supplementation on different clinical aspects of MELAS syndrome are needed. Copyright © 2014 Elsevier Ltd. All rights reserved.

The appearance of ADCs in the non-affected areas of the patients with MELAS

International Nuclear Information System (INIS)

Liu, Zhenghua; Liu, Xiwei; Hui, Lihong; Xie, Sheng; Xiao, Jiangxi; Jiang, Xuexiang; Zhao, Danhua; Wang, Xiaoying

2011-01-01

The exact mechanism of the mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) remain unclear. Diffusion-weighted imaging (DWI) is a magnetic resonance (MR) imaging technique for studying the pathophysiologic change of the MELAS. The purpose of the study is to see whether the apparent diffusion coefficient (ADC) of MELAS in the non-affected areas is different from the ADC of the normal subjects and to speculate the pathophysiological mechanisms of the MELAS. Sixteen cases of MELAS were retrospectively analyzed. Thirty healthy subjects were chosen to constitute the control group. All of them were performed on the 3.0T whole-body MR scanner with axial view T2 fluid attenuated inversion recovery (flair), T2-weighted imaging, T1flair, and DWI. An ADC map was reconstructed in the workstation. Two to five regions of interest were put in the non-affected frontal lobe and basal ganglia. All data took statistical analysis. There were significant differences between the ADC of the patients with MELAS and the controls in the non-affected areas, including the superior frontal gyrus, precentral gyrus, corpus striatum, thalamus, and white matter of the semi-oval centrum. ADCs in the non-affected areas of the patients with MELAS are higher than those of the normal subjects. Pathological changes take place in the non-affected areas of the patients with MELAS. (orig.)

The appearance of ADCs in the non-affected areas of the patients with MELAS

Energy Technology Data Exchange (ETDEWEB)

Liu, Zhenghua; Liu, Xiwei; Hui, Lihong; Xie, Sheng; Xiao, Jiangxi; Jiang, Xuexiang [Peking University First Hospital, Center for Functional Imaging, Peking University, The Department of Radiology, Beijing (China); Zhao, Danhua [Peking University First Hospital, The Department of Neurology, Beijing (China); Wang, Xiaoying [Peking University First Hospital, Center for Functional Imaging, Peking University, The Department of Radiology, Beijing (China); Peking University First Hospital, The Department of Radiology, 8, Xishiku Street, Xicheng District, Beijing (China)

2011-04-15

The exact mechanism of the mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) remain unclear. Diffusion-weighted imaging (DWI) is a magnetic resonance (MR) imaging technique for studying the pathophysiologic change of the MELAS. The purpose of the study is to see whether the apparent diffusion coefficient (ADC) of MELAS in the non-affected areas is different from the ADC of the normal subjects and to speculate the pathophysiological mechanisms of the MELAS. Sixteen cases of MELAS were retrospectively analyzed. Thirty healthy subjects were chosen to constitute the control group. All of them were performed on the 3.0T whole-body MR scanner with axial view T2 fluid attenuated inversion recovery (flair), T2-weighted imaging, T1flair, and DWI. An ADC map was reconstructed in the workstation. Two to five regions of interest were put in the non-affected frontal lobe and basal ganglia. All data took statistical analysis. There were significant differences between the ADC of the patients with MELAS and the controls in the non-affected areas, including the superior frontal gyrus, precentral gyrus, corpus striatum, thalamus, and white matter of the semi-oval centrum. ADCs in the non-affected areas of the patients with MELAS are higher than those of the normal subjects. Pathological changes take place in the non-affected areas of the patients with MELAS. (orig.)

Arrhythmia as a cardiac manifestation in MELAS syndrome.

Science.gov (United States)

Thomas, Tamara; Craigen, William J; Moore, Ryan; Czosek, Richard; Jefferies, John L

2015-09-01

A 44-year-old female with a diagnosis of mitochondrial myopathy, encephalopathy and stroke-like episodes (MELAS) syndrome had progressive left ventricular hypertrophy (LVH) on echocardiogram. A Holter monitor demonstrated episodes of non-sustained atrial tachycardia, a finding not been previously described in this population. This unique case of MELAS syndrome demonstrates the known associated cardiac manifestation of LVH and the new finding of atrial tachycardia which may represent the potential for subclinical arrhythmia in this population.

Cognitive impairment, clinical severity and MRI changes in MELAS syndrome.

Science.gov (United States)

Kraya, Torsten; Neumann, Lena; Paelecke-Habermann, Yvonne; Deschauer, Marcus; Stoevesandt, Dietrich; Zierz, Stephan; Watzke, Stefan

2017-12-29

To examine clinical severity, cognitive impairment, and MRI changes in patients with MELAS syndrome. Cognitive-mnestic functions, brain MRI (lesion load, cella media index) and clinical severity of ten patients with MELAS syndrome were examined. All patients carried the m.3243A>G mutation. The detailed neuropsychological assessment revealed cognitive deficits in attention, executive function, visuoperception, and -construction. There were significant correlations between these cognitive changes, lesion load in MRI, disturbances in everyday life (clinical scale), and high scores in NMDAS. Patients with MELAS syndrome showed no global neuropsychological deficit, but rather distinct cognitive deficits. Copyright © 2018 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

Anesthetic management of an obstetric patient with MELAS syndrome: case report and literature review.

Science.gov (United States)

Maurtua, M; Torres, A; Ibarra, V; DeBoer, G; Dolak, J

2008-10-01

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS syndrome) is a mitochondrial disorder associated with neurologic, cardiac, neuromuscular, hepatic, metabolic and gastrointestinal dysfunction and potential anesthetic and obstetric complications. The case of a parturient with MELAS syndrome requiring labor analgesia is presented. A Medline literature search limited to the English language was undertaken to review cases of MELAS syndrome. Based on our experience and literature review, parturients with MELAS syndrome appear to benefit from neuraxial analgesia and anesthesia, which blunt excessive oxygen consumption and acidosis.

ELT-MELAS analyzer and its on-line programs

International Nuclear Information System (INIS)

Anikeev, V.B.; Berezhnoj, V.A.; Glupova

1976-01-01

ELT-MELAS device constructed for an automatic analysis of pictures from big bubble chambers is described. It is controlled by a medium-size ICL-1903A computer and has two measuring modes: analysis of the ''agreement'' signal and digitation of slice-scans. Main features of the hardware and of on-line controlling and diagnostic software are presented. The test results of the MELAS complex as well as preliminary results of the scan-slice measurements of pictures from 15sup(') chamber are given

Frequency of MELAS main mutation in a phenotype-targeted young ischemic stroke patient population.

Science.gov (United States)

Tatlisumak, Turgut; Putaala, Jukka; Innilä, Markus; Enzinger, Christian; Metso, Tiina M; Curtze, Sami; von Sarnowski, Bettina; Amaral-Silva, Alexandre; Jungehulsing, Gerhard Jan; Tanislav, Christian; Thijs, Vincent; Rolfs, Arndt; Norrving, Bo; Fazekas, Franz; Suomalainen, Anu; Kolodny, Edwin H

2016-02-01

Mitochondrial diseases, predominantly mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), may occasionally underlie or coincide with ischemic stroke (IS) in young and middle-aged individuals. We searched for undiagnosed patients with MELAS in a target subpopulation of unselected young IS patients enrolled in the Stroke in Young Fabry Patients study (sifap1). Among the 3291 IS patients aged 18-55 years recruited to the sifap1 study at 47 centers across 14 European countries, we identified potential MELAS patients with the following phenotypic features: (a) diagnosed cardiomyopathy or (b) presence of two of the three following findings: migraine, short stature (≤165 cm for males; ≤155 cm for females), and diabetes. Identified patients' blood samples underwent analysis of the common MELAS mutation, m.3243A>G in the MTTL1 gene of mitochondrial DNA. Clinical and cerebral MRI features of the mutation carriers were reviewed. We analyzed blood samples of 238 patients (177 with cardiomyopathy) leading to identification of four previously unrecognized MELAS main mutation carrier-patients. Their clinical and MRI characteristics were within the expectation for common IS patients except for severe hearing loss in one patient and hyperintensity of the pulvinar thalami on T1-weighted MRI in another one. Genetic testing for the m.3243A>G MELAS mutation in young patients with IS based on phenotypes suggestive of mitochondrial disease identifies previously unrecognized carriers of MELAS main mutation, but does not prove MELAS as the putative cause.

Nucleotide sequence of the melA gene, coding for alpha-galactosidase in Escherichia coli K-12.

OpenAIRE

Liljeström, P L; Liljeström, P

1987-01-01

Melibiose uptake and hydrolysis in E.coli is performed by the MelB and MelA proteins, respectively. We report the cloning and sequencing of the melA gene. The nucleotide sequence data showed that melA codes for a 450 amino acid long protein with a molecular weight of 50.6 kd. The sequence data also supported the assumption that the mel locus forms an operon with melA in proximal position. A comparison of MelA with alpha-galactosidase proteins from yeast and human origin showed that these prot...

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.

Total intravenous anesthesia with propofol and remifentanil in a patient with MELAS syndrome -A case report-.

Science.gov (United States)

Park, Jin Suk; Baek, Chong Wha; Kang, Hyun; Cha, Su Man; Park, Jung Won; Jung, Yong Hun; Woo, Young-Cheol

2010-04-01

A 23-year-old woman with MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) underwent a laparoscopy-assisted appendectomy. MELAS syndrome is a multisystemic disease caused by mitochondrial dysfunction. General anesthesia has several potential hazards to patients with MELAS syndrome, such as malignant hyperthermia, hypothermia, and metabolic acidosis. In this case, anesthesia was performed with propofol, remifentanil TCI, and atracurium without any surgical or anesthetic complications. We discuss the anesthetic effects of MELAS syndrome.

Bollywood Dreams? The Rise of the Asian Mela as a Global Cultural Phenomenon

Directory of Open Access Journals (Sweden)

Melanie Smith

2006-03-01

Full Text Available This article will examine some of the complexities inherent in the development of Asian Mela festivals from small-scale community-based events in India, to national celebrations of Diasporic culture in Western countries. Like Caribbean Carnivals, Melas are becoming more popular as a global cultural tourism phenomenon and are increasingly being promoted to white and tourist audiences. This similarly engenders fears of cultural dilution, distortion, and ‘Othering’. The programming of Melas is apparently keeping pace with the exporting, re-packaging and hybridisation of other forms of Asian culture, such as cuisine, music, fashion, and cinema. But does this symbolise a Bollywood dream or just another post-colonial appropriation of indigenous or Disaporic cultures? Cultural protectionism is certainly a contentious issue within Diasporic communities, where inter-generational differences of opinion can lead to conflict and confusion. Identity construction is complex and worthy of further examination in the context of Melas, which traditionally served to celebrate ethnic community and folk cultures and identities, but are increasingly becoming a showcase for global and hybridised cultural forms. The article will examine these issues, as well as providing an analysis of the factors and mechanisms that are driving the development of Melas forward. This will include the role and vision of artistic directors of Melas, the contribution of ethnic communities to cultural continuity, and issues relating to audience and tourism development. A case study of the Edinburgh Mela will be presented, which exemplifies a number of the aforementioned issues, focusing in particular on national and Diasporic identity construction, and the tensions between popular and traditional cultural forms.

Whole blood genome-wide expression profiling and network analysis suggest MELAS master regulators.

Science.gov (United States)

Mende, Susanne; Royer, Loic; Herr, Alexander; Schmiedel, Janet; Deschauer, Marcus; Klopstock, Thomas; Kostic, Vladimir S; Schroeder, Michael; Reichmann, Heinz; Storch, Alexander

2011-07-01

The heteroplasmic mitochondrial DNA (mtDNA) mutation A3243G causes the mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome as one of the most frequent mitochondrial diseases. The process of reconfiguration of nuclear gene expression profile to accommodate cellular processes to the functional status of mitochondria might be a key to MELAS disease manifestation and could contribute to its diverse phenotypic presentation. To determine master regulatory protein networks and disease-modifying genes in MELAS syndrome. Analyses of whole blood transcriptomes from 10 MELAS patients using a novel strategy by combining classic Affymetrix oligonucleotide microarray profiling with regulatory and protein interaction network analyses. Hierarchical cluster analysis elucidated that the relative abundance of mutant mtDNA molecules is decisive for the nuclear gene expression response. Further analyses confirmed not only transcription factors already known to be involved in mitochondrial diseases (such as TFAM), but also detected the hypoxia-inducible factor 1 complex, nuclear factor Y and cAMP responsive element-binding protein-related transcription factors as novel master regulators for reconfiguration of nuclear gene expression in response to the MELAS mutation. Correlation analyses of gene alterations and clinico-genetic data detected significant correlations between A3243G-induced nuclear gene expression changes and mutant mtDNA load as well as disease characteristics. These potential disease-modifying genes influencing the expression of the MELAS phenotype are mainly related to clusters primarily unrelated to cellular energy metabolism, but important for nucleic acid and protein metabolism, and signal transduction. Our data thus provide a framework to search for new pathogenetic concepts and potential therapeutic approaches to treat the MELAS syndrome.

MRI evaluation of cerebral perfusion changes in patients with MELAS syndrome

International Nuclear Information System (INIS)

Xie Sheng; Qi Zhaoyue; Xiao Jiangxi; Jiang Xuexiang; Yang Yanling

2008-01-01

Objective: To detect the changes of cerebral perfusion in patients with MELAS syndrome by using MR perfusion technique. Methods: Thirteen patients with MELAS syndrome and 13 controls with normal neurological conditions were scanned with the sequence of flow-sensitive alternating inversion recovery exempting separate T 1 measurement (FAIREST). Their rCBF values were obtained in regions of bilateral basilar nuclei and thalami, as well as bilateral temporal lobes and occipital lobes. Regression analysis was carried out to determine the effect of location and side on the measurement of rCBF in controls. One-way ANOVA was conducted to compare rCBF values among the control group, the lesion ROIs and normal ROIs of the MELAS syndrome group. Results: The values of rCBF were 0.83 ± 0.23, 1.17± 0.30, 0.93 ± 0.28, and 1.11 ± 0.25 for the left basilar ganglia, thalamus, temporal lobe, and occipital lobe respectively, while they were 0.77 ± 0.15, 1.03 ± 0.34, 1.06 ± 0.23, and 1.09 ± 0.23 for the right basilar ganglia, thalamus, temporal lobe, and occipital lobe respectively. Regression analysis revealed no effect of location and side on the rCBF (P>0.05). The rCBF value for control group was 1.00 + 0. 28, while it was 1.01 ± 0.31 for the normal ROIs and 1.95 ± 0.43 for the lesion ROIs in the MELAS syndrome group (F=54.99, P<0.01). The rCBF of the lesion ROIs in the MELAS syndrome group was significantly higher than the normal ROIs and the control group. Conclusion: CBF maps can reveal changes of cerebral blood flow in patients with ictal MELAS, which suggests increased perfusion in the stroke-like lesions. (authors)

Mitochondrial Encephalomyopathy With Lactic Acidosis and Stroke-Like Episodes-MELAS Syndrome.

Science.gov (United States)

Henry, Caitlin; Patel, Neema; Shaffer, William; Murphy, Lillian; Park, Joe; Spieler, Bradley

2017-01-01

Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome is a rare inherited disorder that results in waxing and waning nervous system and muscle dysfunction. MELAS syndrome may overlap with other neurologic disorders but shows distinctive imaging features. We present the case of a 28-year-old female with atypical stroke-like symptoms, a strong family history of stroke-like symptoms, and a relapsing-remitting course for several years. We discuss the imaging features distinctive to the case, the mechanism of the disease, typical presentation, imaging diagnosis, and disease management. This case is a classic example of the relapse-remitting MELAS syndrome progression with episodic clinical flares and fluctuating patterns of stroke-like lesions on imaging. MELAS is an important diagnostic consideration when neuroimaging reveals a pattern of disappearing and relapsing cortical brain lesions that may occur in different areas of the brain and are not necessarily limited to discrete vascular territories. Future studies should investigate disease mechanisms at the cellular level and the value of advanced magnetic resonance imaging techniques for a targeted approach to therapy.

Computed tomography and angiography in MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes)

International Nuclear Information System (INIS)

Hasuo, K.; Tamura, S.; Yasumori, K.; Uchino, A.; Masuda, K.; Goda, S.; Ishimoto, S.; Kamikaseda, K.; Wakuta, Y.; Kishi, M.

1987-01-01

Among mitochondrial encephalomyopathies, MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes, Pavlakis et al., 1983) is recognized as a distinct syndrome characterized by generalized convulsions and recurrrent stroke-like episodes. The neuroradiological findings of three patients with MELAS are reported here. Retrospective review shows that MELAS should be included in the differential diagnosis of infarct-like lesions of the cerebrum. (orig.)

Cerebral hyperperfusion and decreased cerebrovascular reactivity correlate with neurologic disease severity in MELAS.

Science.gov (United States)

Rodan, L H; Poublanc, J; Fisher, J A; Sobczyk, O; Wong, T; Hlasny, E; Mikulis, D; Tein, I

2015-05-01

To study the mechanisms underlying stroke-like episodes (SLEs) in MELAS syndrome. We performed a case control study in 3 siblings with MELAS syndrome (m.3243A>G tRNA(Leu(UUR))) with variable % mutant mtDNA in blood (35 to 59%) to evaluate regional cerebral blood flow (CBF) and arterial cerebrovascular reactivity (CVR) compared to age- and sex-matched healthy study controls and a healthy control population. Subjects were studied at 3T MRI using arterial spin labeling (ASL) to measure CBF; CVR was measured as a change in % Blood Oxygen Level Dependent signal (as a surrogate of CBF) to repeated 10 mmHg step increase in arterial partial pressure of CO2 (PaCO2). MELAS siblings had decreased CVR (p ≤ 0.002) and increased CBF (p MELAS disease severity and mutation load were inversely correlated with Interictal CVR and directly correlated with frontal CBF. These metrics offer further insight into the cerebrovascular hemodynamics in MELAS syndrome and may serve as noninvasive prognostic markers to stratify risk for SLEs. Class III. Copyright © 2015 © Elsevier B.V. and Mitochondria Research Society. Published by Elsevier B.V. All rights reserved.

Renal involvement in MELAS syndrome - a series of 5 cases and review of the literature.

Science.gov (United States)

Seidowsky, Alexandre; Hoffmann, Maxime; Glowacki, François; Dhaenens, Claire-Marie; Devaux, Jean-Philippe; de Sainte Foy, Celia Lessore; Provot, François; Gheerbrant, Jean-Dominique; Hummel, Aurelie; Hazzan, Marc; Dracon, Michel; Dieux-Coeslier, Anne; Copin, Marie-Christine; Noël, Christian; Buob, David

2013-12-01

Renal dysfunction is increasingly recognized as a potential clinical feature of mitochondrial cytopathies such as mitochondrial encephalomyopathy, lacticacidosis and stroke-like episodes (MELAS) syndrome. Five cases of MELAS syndrome with renal involvement from 4 unrelated families are presented in this case series. Three of the 5 patients had a history of maternally-inherited diabetes and/or deafness. Focal and segmental glomerulosclerosis and arteriolar hyaline thickening were the most striking findings on renal biopsy. In addition to clinical presentation with the typical symptoms of MELAS syndrome, genetic testing in these patients identified the A3243G point mutation in the tRNALeu gene of the mitochondrial DNA (mtDNA). The diagnosis of MELAS syndrome was thus considered to be unequivocal. The incidence of kidney disease in MELAS syndrome may be underestimated although a study is required to investigate this hypothesis. As the A3243G mtDNA mutation leads to a progressive adult-onset form of focal segmental glomerulosclerosis (FSGS), screening for the MELAS A3243G mtDNA mutation should therefore be performed especially in patients with maternally-inherited diabetes or hearing loss presenting with FSGS.

Mitochondrial Encephalomyopathy With Lactic Acidosis and Stroke-Like Episodes—MELAS Syndrome

Science.gov (United States)

Henry, Caitlin; Patel, Neema; Shaffer, William; Murphy, Lillian; Park, Joe

2017-01-01

Background: Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome is a rare inherited disorder that results in waxing and waning nervous system and muscle dysfunction. MELAS syndrome may overlap with other neurologic disorders but shows distinctive imaging features. Case Report: We present the case of a 28-year-old female with atypical stroke-like symptoms, a strong family history of stroke-like symptoms, and a relapsing-remitting course for several years. We discuss the imaging features distinctive to the case, the mechanism of the disease, typical presentation, imaging diagnosis, and disease management. Conclusion: This case is a classic example of the relapse-remitting MELAS syndrome progression with episodic clinical flares and fluctuating patterns of stroke-like lesions on imaging. MELAS is an important diagnostic consideration when neuroimaging reveals a pattern of disappearing and relapsing cortical brain lesions that may occur in different areas of the brain and are not necessarily limited to discrete vascular territories. Future studies should investigate disease mechanisms at the cellular level and the value of advanced magnetic resonance imaging techniques for a targeted approach to therapy. PMID:29026367

When should MELAS (Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes) be the diagnosis?

Science.gov (United States)

Lorenzoni, Paulo José; Werneck, Lineu Cesar; Kay, Cláudia Suemi Kamoi; Silvado, Carlos Eduardo Soares; Scola, Rosana Herminia

2015-11-01

Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes (MELAS) is a rare mitochondrial disorder. Diagnostic criteria for MELAS include typical manifestations of the disease: stroke-like episodes, encephalopathy, evidence of mitochondrial dysfunction (laboratorial or histological) and known mitochondrial DNA gene mutations. Clinical features of MELAS are not necessarily uniform in the early stages of the disease, and correlations between clinical manifestations and physiopathology have not been fully elucidated. It is estimated that point mutations in the tRNALeu(UUR) gene of the DNAmt, mainly A3243G, are responsible for more of 80% of MELAS cases. Morphological changes seen upon muscle biopsy in MELAS include a substantive proportion of ragged red fibers (RRF) and the presence of vessels with a strong reaction for succinate dehydrogenase. In this review, we discuss mainly diagnostic criterion, clinical and laboratory manifestations, brain images, histology and molecular findings as well as some differential diagnoses and current treatments.

Screening of effective pharmacological treatments for MELAS syndrome using yeasts, fibroblasts and cybrid models of the disease.

Science.gov (United States)

Garrido-Maraver, Juan; Cordero, Mario D; Moñino, Irene Domínguez; Pereira-Arenas, Sheila; Lechuga-Vieco, Ana V; Cotán, David; De la Mata, Mario; Oropesa-Ávila, Manuel; De Miguel, Manuel; Bautista Lorite, Juan; Rivas Infante, Eloy; Alvarez-Dolado, Manuel; Navas, Plácido; Jackson, Sandra; Francisci, Silvia; Sánchez-Alcázar, José A

2012-11-01

MELAS (mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes) is a mitochondrial disease most usually caused by point mutations in tRNA genes encoded by mitochondrial DNA (mtDNA). Approximately 80% of cases of MELAS syndrome are associated with a m.3243A > G mutation in the MT-TL1 gene, which encodes the mitochondrial tRNALeu (UUR). Currently, no effective treatments are available for this chronic progressive disorder. Treatment strategies in MELAS and other mitochondrial diseases consist of several drugs that diminish the deleterious effects of the abnormal respiratory chain function, reduce the presence of toxic agents or correct deficiencies in essential cofactors. We evaluated the effectiveness of some common pharmacological agents that have been utilized in the treatment of MELAS, in yeast, fibroblast and cybrid models of the disease. The yeast model harbouring the A14G mutation in the mitochondrial tRNALeu(UUR) gene, which is equivalent to the A3243G mutation in humans, was used in the initial screening. Next, the most effective drugs that were able to rescue the respiratory deficiency in MELAS yeast mutants were tested in fibroblasts and cybrid models of MELAS disease. According to our results, supplementation with riboflavin or coenzyme Q(10) effectively reversed the respiratory defect in MELAS yeast and improved the pathologic alterations in MELAS fibroblast and cybrid cell models. Our results indicate that cell models have great potential for screening and validating the effects of novel drug candidates for MELAS treatment and presumably also for other diseases with mitochondrial impairment. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Homogentisic acid is the product of MelA, which mediates melanogenesis in the marine bacterium Shewanella colwelliana D.

OpenAIRE

Coon, S L; Kotob, S; Jarvis, B B; Wang, S; Fuqua, W C; Weiner, R M

1994-01-01

Shewanella colwelliana D is a marine procaryote which produces a diffusible brown pigment that correlates with melA gene expression. Previously, melA had been cloned, sequenced, and expressed in Escherichia coli; however, the reaction product of MelA had not been identified. This report identifies that product as homogentisic acid, provides evidence that the pigment is homogentisic acid-melanin (pyomelanin), and suggests that MelA is p-hydroxyphenylpyruvate hydroxylase. This is the first repo...

Managing the Earth's Biggest Mass Gathering Event and WASH Conditions: Maha Kumbh Mela (India).

Science.gov (United States)

Baranwal, Annu; Anand, Ankit; Singh, Ravikant; Deka, Mridul; Paul, Abhishek; Borgohain, Sunny; Roy, Nobhojit

2015-04-13

Mass gatherings including a large number of people makes the planning and management of the event a difficult task. Kumbh Mela is one such, internationally famous religious mass gathering. It creates the substantial challenge of creating a temporary city in which millions of people can stay for a defined period of time. The arrangements need to allow this very large number of people to reside with proper human waste disposal, medical services, adequate supplies of food and clean water, transportation etc. We report a case study of Maha Kumbh, 2013 which focuses on the management and planning that went into the preparation of Kumbh Mela and understanding its water, sanitation and hygiene conditions. It was an observational cross-sectional study, the field work was done for 13 days, from 21 January to 2 February 2013. Our findings suggest that the Mela committee and all other agencies involved in Mela management proved to be successful in supervising the event and making it convenient, efficient and safe. Health care services and water sanitation and hygiene conditions were found to be satisfactory. BhuleBhatke Kendra (Center for helping people who got separated from their families) had the major task of finding missing people and helping them to meet their families. Some of the shortfalls identified were that drainage was a major problem and some fire incidents were reported. Therefore, improvement in drainage facilities and reduction in fire incidents are essential to making Mela cleaner and safer. The number of persons per toilet was high and there were no separate toilets for males and females. Special facilities and separate toilets for men and women will improve their stay in Mela. Inculcation of modern methods and technologies are likely to help in supporting crowd management and improving water, sanitation and hygiene conditions in the continuously expanding KumbhMela, in the coming years.

Treatment options for mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome.

Science.gov (United States)

Santa, Kristin M

2010-11-01

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare neurodegenerative disease caused by the decreased ability of cells to produce sufficient energy in the form of adenosine 5'-triphosphate. Although it is one of the most common maternally inherited mitochondrial disorders, its exact incidence is unknown. Caused most frequently by an A-to-G point mutation at the 3243 position in the mitochondrial DNA, MELAS syndrome has a broad range of clinical manifestations and a highly variable course. The classic neurologic characteristics include encephalopathy, seizures, and stroke-like episodes. In addition to its neurologic manifestations, MELAS syndrome exhibits multisystem effects including cardiac conduction defects, diabetes mellitus, short stature, myopathy, and gastrointestinal disturbances. Unfortunately, no consensus guidelines outlining standard drug regimens exist for this syndrome. Many of the accepted therapies used in treating MELAS syndrome have been identified through a small number of clinical trials or isolated case reports. Currently, the drugs most often used include antioxidants and various vitamins aimed at minimizing the demands on the mitochondria and supporting and maximizing their function. Some of the most frequently prescribed agents include coenzyme Q(10), l-arginine, B vitamins, and levocarnitine. Although articles describing MELAS syndrome are available, few specifically target education for clinical pharmacists. This article will provide pharmacists with a practical resource to enhance their understanding of MELAS syndrome in order to provide safe and effective pharmaceutical care.

[A study on the expression of anti-mitochondrial antibody in the brain of patients with MELAS syndrome].

Science.gov (United States)

Qi, Xiao-Kun; Yao, Sheng; Wang, Hai-Yan; Piao, Yue-Shan; Lu, De-Hong; Yuan, Yun

2009-04-01

To investigate the pathological changes and pathogenesis of the MELAS syndrome (mitochondrial encephalopathy lactic acidosis stroke-like episodes) by using the method of immunohistochemical staining in the brain biopsy specimens with anti-mitochondrial antibody (AMA). We performed immunohistochemical staining in 3 confirmed MELAS patients' paraffin-imbued brain biopsy specimens. Small vessel proliferation and the uneven thickness of the wall were found in the 3 MELAS patients. A lot of brown deposits was shown in the wall of small vessels and also noted in neurons. The main pathological change in the MELAS brain biopsy immunohistochemical staining with AMA was the small vessel proliferation, indicating that abnormal mitochondria accumulated in the vascular smooth muscle, endothelial cell and neurons of the lesion sites. This finding was consistent with the electron microscopic discovery and valuable for the diagnosis of MELAS.

Pathology of mitochondria in MELAS syndrome: an ultrastructural study.

Science.gov (United States)

Felczak, Paulina; Lewandowska, Eliza; Stępniak, Iwona; Ołdak, Monika; Pollak, Agnieszka; Lechowicz, Urszula; Pasennik, Elżbieta; Stępień, Tomasz; Wierzba-Bobrowicz, Teresa

Ultrastructural changes in skeletal muscle biopsy in a 24-year-old female patient with clinically suspected mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes (MELAS) syndrome are presented. We observed proliferation and/or pleomorphism of mitochondria in skeletal muscle and smooth muscle cells of arterioles, as well as in pericytes of capillaries. Paracrystalline inclusions were found only in damaged mitochondria of skeletal muscle. Genetic testing revealed a point mutation in A3243G tRNALeu(UUR) typical for MELAS syndrome. We conclude that differentiated pathological changes of mitochondria in the studied types of cells may be associated with the different energy requirements of these cells.

Melas Chasma, Day and Night.

Science.gov (United States)

2002-01-01

This image is a mosaic of day and night infrared images of Melas Chasma taken by the camera system on NASA's Mars Odyssey spacecraft. The daytime temperature images are shown in black and white, superimposed on the martian topography. A single nighttime temperature image is superimposed in color. The daytime temperatures range from approximately -35 degrees Celsius (-31 degrees Fahrenheit) in black to -5 degrees Celsius (23 degrees Fahrenheit) in white. Overlapping landslides and individual layers in the walls of Melas Chasma can be seen in this image. The landslides flowed over 100 kilometers (62 miles) across the floor of Melas Chasma, producing deposits with ridges and grooves of alternating warm and cold materials that can still be seen. The temperature differences in the daytime images are due primarily to lighting effects, where sunlit slopes are warm (bright) and shadowed slopes are cool (dark). The nighttime temperature differences are due to differences in the abundance of rocky materials that retain their heat at night and stay relatively warm (red). Fine grained dust and sand (blue) cools off more rapidly at night. These images were acquired using the thermal infrared imaging system infrared Band 9, centered at 12.6 micrometers.Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for NASA's Office of Space Science in Washington, D.C. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. Additional science partners are located at the Russian Aviation and Space Agency and at Los Alamos National Laboratories, New Mexico. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL. Aviation and Space Agency and at Los Alamos National Laboratories

Impaired nitric oxide production in children with MELAS syndrome and the effect of arginine and citrulline supplementation.

Science.gov (United States)

El-Hattab, Ayman W; Emrick, Lisa T; Hsu, Jean W; Chanprasert, Sirisak; Almannai, Mohammed; Craigen, William J; Jahoor, Farook; Scaglia, Fernando

2016-04-01

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most frequent maternally inherited mitochondrial disorders. The pathogenesis of this syndrome is not fully understood and believed to result from several interacting mechanisms including impaired mitochondrial energy production, microvasculature angiopathy, and nitric oxide (NO) deficiency. NO deficiency in MELAS syndrome is likely to be multifactorial in origin with the decreased availability of the NO precursors, arginine and citrulline, playing a major role. In this study we used stable isotope infusion techniques to assess NO production in children with MELAS syndrome and healthy pediatric controls. We also assessed the effect of oral arginine and citrulline supplementations on NO production in children with MELAS syndrome. When compared to control subjects, children with MELAS syndrome were found to have lower NO production, arginine flux, plasma arginine, and citrulline flux. In children with MELAS syndrome, arginine supplementation resulted in increased NO production, arginine flux, and arginine concentration. Citrulline supplementation resulted in a greater increase of these parameters. Additionally, citrulline supplementation was associated with a robust increase in citrulline concentration and flux and de novo arginine synthesis rate. The greater effect of citrulline in increasing NO production is due to its greater ability to increase arginine availability particularly in the intracellular compartment in which NO synthesis takes place. This study, which is the first one to assess NO metabolism in children with mitochondrial diseases, adds more evidence to the notion that NO deficiency occurs in MELAS syndrome, suggests a better effect for citrulline because of its greater role as NO precursor, and indicates that impaired NO production occurs in children as well as adults with MELAS syndrome. Thus, the initiation of treatment with NO precursors may be

MELAS Syndrome and Kidney Disease Without Fanconi Syndrome or Proteinuria: A Case Report.

Science.gov (United States)

Rudnicki, Michael; Mayr, Johannes A; Zschocke, Johannes; Antretter, Herwig; Regele, Heinz; Feichtinger, René G; Windpessl, Martin; Mayer, Gert; Pölzl, Gerhard

2016-12-01

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS syndrome) represents one of the most frequent mitochondrial disorders. The majority of MELAS cases are caused by m.3243A>G mutation in the mitochondrial MT-TL1 gene, which encodes the mitochondrial tRNA Leu(UUR) . Kidney involvement usually manifests as Fanconi syndrome or focal segmental glomerulosclerosis. We describe a patient with MELAS mutation, cardiomyopathy, and chronic kidney disease without Fanconi syndrome, proteinuria, or hematuria. While the patient was waitlisted for heart transplantation, her kidney function deteriorated from an estimated glomerular filtration rate of 33 to 20mL/min/1.73m 2 within several months. Kidney biopsy was performed to distinguish decreased kidney perfusion from intrinsic kidney pathology. Histologic examination of the biopsy specimen showed only a moderate degree of tubular atrophy and interstitial fibrosis, but quantitative analysis of the m.3243A>G mitochondrial DNA mutation revealed high heteroplasmy levels of 89% in the kidney. Functional assessment showed reduced activity of mitochondrial enzymes in kidney tissue, which was confirmed by immunohistology. In conclusion, we describe an unusual case of MELAS syndrome with chronic kidney disease without apparent proteinuria or tubular disorders associated with Fanconi syndrome, but widespread interstitial fibrosis and a high degree of heteroplasmy of the MELAS specific mutation and low mitochondrial activity in the kidney. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Speech-Language and swallowing manifestations and rehabilitation in an 11-year-old girl with MELAS syndrome.

Science.gov (United States)

Vandana, V P; Bindu, Parayil Sankaran; Sonam, Kothari; Taly, Arun B; Gayathri, N; Madhu, N; Sinha, S

2015-01-01

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare mitochondrial disease. The available studies on MELAS syndrome are limited to evaluation of radiological, audiological, genetic, and neurological findings. Among the various neurological manifestations, speech-language and swallowing manifestations are less discussed in the literature. This report describes the speech-language and swallowing function in an 11-year-old girl with MELAS syndrome. The intervention over a period of 6 months is discussed.

The mitochondrial DNA 10197 G > A mutation causes MELAS/Leigh overlap syndrome presenting with acute auditory agnosia.

Science.gov (United States)

Leng, Yinglin; Liu, Yuhe; Fang, Xiaojing; Li, Yao; Yu, Lei; Yuan, Yun; Wang, Zhaoxia

2015-04-01

Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes/Leigh (MELAS/LS) overlap syndrome is a mitochondrial disorder subtype with clinical and magnetic resonance imaging (MRI) features that are characteristic of both MELAS and Leigh syndrome (LS). Here, we report an MELAS/LS case presenting with cortical deafness and seizures. Cranial MRI revealed multiple lesions involving bilateral temporal lobes, the basal ganglia and the brainstem, which conformed to neuroimaging features of both MELAS and LS. Whole mitochondrial DNA (mtDNA) sequencing and PCR-RFLP revealed a de novo heteroplasmic m.10197 G > A mutation in the NADH dehydrogenase subunit 3 gene (ND3), which was predicted to cause an alanine to threonine substitution at amino acid 47. Although the mtDNA m.10197 G > A mutation has been reported in association with LS, Leber hereditary optic neuropathy and dystonia, it has never been linked with MELAS/LS overlap syndrome. Our patient therefore expands the phenotypic spectrum of the mtDNA m.10197 G > A mutation.

Acute cortical deafness in a child with MELAS syndrome.

Science.gov (United States)

Pittet, Marie P; Idan, Roni B; Kern, Ilse; Guinand, Nils; Van, Hélène Cao; Toso, Seema; Fluss, Joël

2016-05-01

Auditory impairment in mitochondrial disorders are usually due to peripheral sensorineural dysfunction. Central deafness is only rarely reported. We report here an 11-year-old boy with MELAS syndrome who presented with subacute deafness after waking up from sleep. Peripheral hearing loss was rapidly excluded. A brain MRI documented bilateral stroke-like lesions predominantly affecting the superior temporal lobe, including the primary auditory cortex, confirming the central nature of deafness. Slow recovery was observed in the following weeks. This case serves to illustrate the numerous challenges caused by MELAS and the unusual occurrence of acute cortical deafness, that to our knowledge has not be described so far in a child in this setting.

[MELAS: Mitochondrial Encephalomyopathy, Lactic Acidosis and Stroke-Like Episodes].

Science.gov (United States)

Murakami, Hidetomo; Ono, Kenjiro

2017-02-01

Mitochondrial disease is caused by a deficiency in the energy supply to cells due to mitochondrial dysfunction. Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) is a mitochondrial disease that presents with stroke-like episodes such as acute onset of neurological deficits and characteristic imaging findings. Stroke-like episodes in MELAS have the following features: 1) neurological deficits due to localization of lesions in the brain, 2) episodes often accompany epilepsy, 3) lesions do not follow the vascular supply area, 4) lesions are more often seen in the posterior brain than in the anterior brain, 5) lesions spread to an adjacent area in the brain, and 6) neurological symptoms often disappear together with imaging findings, but later relapse. About 80% of patients with MELAS have an A-to-G transition mutation at the nucleotide pair 3243 in the dihydrouridine loop of mitochondrial tRNALeu(UUR), which causes the absence of posttranscriptional taurine modification at the wobble nucleotide of mitochondrial tRNALeu(UUR) and disrupts protein synthesis. However, the precise pathophysiology of stroke-like episodes is under investigation, with possible hypotheses for these episodes including mitochondrial angiopathy, mitochondrial cytopathy, and neuron-astrocyte uncoupling. With regard to treatment, L-arginine and taurine have recently been suggested for relief of clinical symptoms.

Advances in the Treatment of MELAS Syndrome: Could Cognitive Rehabilitation Have a Role?

Science.gov (United States)

De Luca, Rosaria; Russo, Margherita; Leonardi, Simona; Spadaro, Letteria; Cicero, Cettina; Naro, Antonino; Bramanti, Placido; Calabrò, Rocco Salvatore

2016-01-01

Mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes syndrome (MELAS) is a rare inherited mitochondrial disorder, commonly due to the m.3243A>G mutation, which typically presents with seizures, headaches, and acute neurological stroke-mimicking deficits. At onset, there is often no general intellectual deterioration in these patients, although specific cognitive deficits in peculiar language domains, visual construction, attention, abstraction, or flexibility may be present. To date, there is no evidence for an effective treatment in individuals with MELAS. Herein, we describe the case of young woman affected by MELAS who underwent an intensive cognitive training by means of the following methods: (a) traditional cognitive training, (b) computerized cognitive training (CCT), and (c) CCT plus a low-intensity aerobic motor exercise. We compared her cognitive and psychological profile at baseline (T0) and at the end of each training (i.e., (Time 1, Time 2, and Time 3 [T3]) using a proper psychometric battery, and we found a greater improvement at T3. Our findings support the idea that the combined CCT with motor training could represent a valuable therapeutic opportunity in MELAS.

Mitochondrial myopathy, encephalopathy, lactate acidosis with stroke-like episodes syndrome (MELAS: A case report

Directory of Open Access Journals (Sweden)

Petrović Igor N.

2012-01-01

Full Text Available Introduction. Mitochondrial encephalopathy, lactacidosis and stroke-like episodes (MELAS represent a multisystemic dysfunction due to various mutations in mitochondrial DNA. Here we report a patient with genetically confirmed MELAS. Case Outline. A patient is presented whose clinical features involved short stature, easy tendency to fatigue, recurrent seizures, progressive cognitive decline, myopathy, sensorineural deafness, diabetes mellitus as well as stroke-like episodes. The major clinical feature of migraine type headache was not present. Neuroimaging studies revealed signs of ischemic infarctions localized in the posterior regions of the brain cortex. Electron microscopy of the skeletal muscle biopsy showed subsarcolemmal accumulation of a large number of mitochondria with paracristal inclusions in the skeletal muscle cells. The diagnosis of MELAS was definitively confirmed by the detection of a specific point mutation A to G at nucleotide position 3243 of mitochondrial DNA. Conclusion. When a relatively young patient without common risk factors for ischemic stroke presents with signs of occipitally localized brain infarctions accompanied with multisystemic dysfunction, MELAS syndrome, it is necessary to conduct investigations in order to diagnose the disease.

New Transfection Agents Based on Liposomes Containing Biosurfactant MEL-A.

Science.gov (United States)

Nakanishi, Mamoru; Inoh, Yoshikazu; Furuno, Tadahide

2013-08-16

Nano vectors are useful tools to deliver foreign DNAs, oligonucleotides, and small interfering double-stranded RNAs (siRNAs) into mammalian cells with gene transfection and gene regulation. In such experiments we have found the liposomes with a biosurfacant mannosylerythriol lipid (MEL-A) are useful because of their high transfer efficiency, and their unique mechanism to transfer genes to target cells with the lowest toxicity. In the present review we will describe our current work, which may contribute to the great advance of gene transfer to target cells and gene regulations. For more than two decades, the liposome technologies have changed dramatically and various methods have been proposed in the fields of biochemistry, cell biology, biotechnology, and so on. In addition, they were towards to pharmaceutics and clinical applications. The liposome technologies were expected to use gene therapy, however, they have not reached a requested goal as of yet. In the present paper we would like to present an approach using a biosurfactant, MEL-A, which is a surface-active compound produced by microorganisms growing on water-insoluble substrates and increases efficiency in gene transfection. The present work shows new transfection agents based on liposomes containing biosurfactant MEL-A.

Mitochondrial encephalomyopathy (MELAS) with mental disorder

International Nuclear Information System (INIS)

Suzuki, T.; Koizumi, J.; Shiraishi, H.; Ofuku, K.; Sasaki, M.; Hori, T.; Ishikawa, N.; Anno, I.; Ohkoshi, N.

1990-01-01

A case of mitochondrial encephalomyopathy (MELAS) with mental disorder is reported. The SPECT study using 123 I-iodoamphetamine (IMP) and MRI study revealed abnormality in the left parieto-occipital areas without abnormality in the brain CT or brain scintigram. These findings suggest a localized dysfunction of the brain capillary endothelium in association with the cerebral involvement of mitochondrial encephalomyopathy. (orig.)

[Expression and significance of respiratory chain enzyme of cells in urine sediment in MELAS syndrome].

Science.gov (United States)

Wu, Hai-rong; Ma, Yi-nan; Qi, Yu; Liu, Hong-gang

2013-04-23

To explore the expression and significance of respiratory chain enzyme of cells in urine sediment in mitochondrial encephalopathy myopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome. Through enzyme histochemistry, the authors analyzed the changes of respiratory chain enzyme in urine sediment in 20 MELAS patients due to mitochondrial A3243G mutation (MELAS group) and 20 health peoples (control group). And the impact on the expression of protein encoded by nuclear DNA (A21347) and mitochondrial DNA (A6404) was detected by immunochemistry. Image pro Plus 6.0 software was used for analysis of absorbance (A) of staining images as staining intensity. The data were expressed as M (Q1, Q3) and analyzed through statistical software. The staining intensity of complexes Iin the MELAS group was lower than that in the control group (0.06(0.01, 0.12) vs 0.12(0.01, 0.62), P = 0.010). The intergroup staining intensity of complex II showed no marked difference. Increased density of blue particle and cytoplasmic gathering was found in 13 cased (65%) of the MELAS group under light microscope. The staining intensity of complexes IV was expressed at a low level in the MELAS group (0.14(0.03, 0.32) vs 0.23(0.06, 0.43), P = 0.038). The expression of protein encoded by nuclear DNA (A21347) was lower than that in the control group (0.05(0.02, 0.45) vs 0.17(0.03, 0.70), P = 0.000). The expression of protein encoded by mitochondrial DNA (A6404) was also lower than that in the control group (0.03(0.01, 0.07) vs 0.15 (0.09, 0.23), P = 0.000). Abnormal change of respiratory chain enzyme in urine sediment in MELAS due to mitochondrial A3243G mutation and a low expression of proteins encoded by two kinds of DNA in complexes IV can help to confirm the genetic diagnosis of mitochondrial encephalomyopathies so that different subtypes may be classified and its pathogenesis elucidated.

POLG1 mutations and stroke like episodes: a distinct clinical entity rather than an atypical MELAS syndrome.

Science.gov (United States)

Cheldi, Antonella; Ronchi, Dario; Bordoni, Andreina; Bordo, Bianca; Lanfranconi, Silvia; Bellotti, Maria Grazia; Corti, Stefania; Lucchini, Valeria; Sciacco, Monica; Moggio, Maurizio; Baron, Pierluigi; Comi, Giacomo Pietro; Colombo, Antonio; Bersano, Anna

2013-01-15

POLG1 mutations have been associated with MELAS-like phenotypes. However given several clinical differences it is unknown whether POLG1 mutations are possible causes of MELAS or give raise to a distinct clinical and genetic entity, named POLG1-associated encephalopathy. We describe a 74 years old man carrying POLG1 mutations presenting with strokes, myopathy and ragged red fibers with some atypical aspects for MELAS such as late onset, lack of cerebral calcification and presence of frontal and occipital MRI lesions better consistent with the POLG associated-encephalopathy spectrum. The lack of available data hampers a definite diagnosis in our patient as well as makes it difficult to compare MELAS, which is a clearly defined clinical syndrome, with POLG1-associated encephalopathy, which is so far a purely molecularly defined syndrome with a quite heterogeneous clinical picture. However, the present report contributes to expand the phenotypic spectrum of POLG1 mutations underlining the importance of searching POLG1 mutations in patients with mitochondrial signs and MELAS like phenotypes but negative for common mtDNA mutations.

Metazoan parasites from odontocetes off New Zealand: new records.

Science.gov (United States)

Lehnert, Kristina; Randhawa, Haseeb; Poulin, Robert

2017-10-01

Information about the parasite fauna of spectacled porpoises and cetaceans from New Zealand waters in general is scarce. This study takes advantage of material archived in collections of the Otago Museum in Dunedin and Massey University in Auckland, sampled from cetacean species found stranded along the New Zealand coastline between 2007 and 2014. Parasites from seven species of cetaceans (spectacled porpoise, Phocoena dioptrica (n = 2 individuals examined); pygmy sperm whale (n = 1); long-finned pilot whale, Globicephala melas (n = 1); Risso's dolphin, Grampus griseus (n = 1); short-beaked common dolphin, Delphinus delphis (n = 7); striped dolphin, Stenella coeruleoalba (n = 3) and dusky dolphin, Lagenorhynchus obscurus (n = 2)) from the respiratory and gastro-intestinal tract, cranial sinus, liver, urogenital and mammary tract, fascia and blubber were investigated. Ten parasite species were identified, belonging to the Nematoda (Stenurus minor, Stenurus globicephalae, Halocercus sp. (Pseudaliidae), Anisakis sp. (Anisakidae), Crassicauda sp. (Crassicaudidae)), Cestoda (Phyllobothrium delphini and Monorygma grimaldii (Phyllobothriidae)), Trematoda (Brachicladium palliata and Brachicladium delphini (Brachicladiidae)) and Crustacea (Scutocyamus antipodensis (Cyamidae)). Some of the parasite species encountered comprises new records for their host. Although the material was not sampled within a systematic parasitological survey, the findings contain valuable new information about the parasite fauna of rare, vagile and vulnerable marine wildlife from a remote oceanic environment.

MELAS syndrome associated with a new mitochondrial tRNA-Val gene mutation (m.1616A>G).

Science.gov (United States)

Toyoshima, Yuka; Tanaka, Yuji; Satomi, Kazuo

2017-09-11

We describe the case of a 40-year-old-man with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome, with cardiomyopathy and severe heart failure. He had a mitochondrial transfer RNA (tRNA) mutation (m.1616A>G) of the (tRNA-Val) gene, and it was not found in MELAS syndrome ever before. The presence of this newly observed tRNA-Val mutation (m.1616A>G) may induce multiple respiratory chain enzyme deficiencies and contribute to MELAS syndrome symptoms that are associated with mitochondrial DNA (mtDNA) mutations. We report that the pathognomonic symptom in MELAS syndrome caused by this newly observed mtDNA mutation may be rapid progression of cardiomyopathy and severe heart failure. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

MELAS syndrome, cardiomyopathy, rhabdomyolysis, and autism associated with the A3260G mitochondrial DNA mutation.

Science.gov (United States)

Connolly, Barbara S; Feigenbaum, Annette S J; Robinson, Brian H; Dipchand, Anne I; Simon, David K; Tarnopolsky, Mark A

2010-11-12

The A to G transition mutation at position 3260 of the mitochondrial genome is usually associated with cardiomyopathy and myopathy. One Japanese kindred reported the phenotype of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS syndrome) in association with the A3260G mtDNA mutation. We describe the first Caucasian cases of MELAS syndrome associated with the A3260G mutation. Furthermore, this mutation was associated with exercise-induced rhabdomyolysis, hearing loss, seizures, cardiomyopathy, and autism in the large kindred. We conclude that the A3260G mtDNA mutation is associated with wide phenotypic heterogeneity with MELAS and other "classical" mitochondrial phenotypes being manifestations. Copyright © 2010 Elsevier Inc. All rights reserved.

Validating tyrosinase homologue melA as a photoacoustic reporter gene for imaging Escherichia coli

Science.gov (United States)

Paproski, Robert J.; Li, Yan; Barber, Quinn; Lewis, John D.; Campbell, Robert E.; Zemp, Roger

2015-10-01

To understand the pathogenic processes for infectious bacteria, appropriate research tools are required for replicating and characterizing infections. Fluorescence and bioluminescence imaging have primarily been used to image infections in animal models, but optical scattering in tissue significantly limits imaging depth and resolution. Photoacoustic imaging, which has improved depth-to-resolution ratio compared to conventional optical imaging, could be useful for visualizing melA-expressing bacteria since melA is a bacterial tyrosinase homologue which produces melanin. Escherichia coli-expressing melA was visibly dark in liquid culture. When melA-expressing bacteria in tubes were imaged with a VisualSonics Vevo LAZR system, the signal-to-noise ratio of a 9× dilution sample was 55, suggesting that ˜20 bacteria cells could be detected with our system. Multispectral (680, 700, 750, 800, 850, and 900 nm) analysis of the photoacoustic signal allowed unmixing of melA-expressing bacteria from blood. To compare photoacoustic reporter gene melA (using Vevo system) with luminescent and fluorescent reporter gene Nano-lantern (using Bruker Xtreme In-Vivo system), tubes of bacteria expressing melA or Nano-lantern were submerged 10 mm in 1% Intralipid, spaced between melA-expressing bacteria even when the tubes were less than 1 mm from each other, while bioluminescence and fluorescence imaging could not resolve the two tubes of Nano-lantern-expressing bacteria even when the tubes were spaced 10 mm from each other. After injecting 100-μL of melA-expressing bacteria in the back flank of a chicken embryo, photoacoustic imaging allowed visualization of melA-expressing bacteria up to 10-mm deep into the embryo. Photoacoustic signal from melA could also be separated from deoxy- and oxy-hemoglobin signal observed within the embryo and chorioallantoic membrane. Our results suggest that melA is a useful photoacoustic reporter gene for visualizing bacteria, and further work

New Transfection Agents Based on Liposomes Containing Biosurfactant MEL-A

Directory of Open Access Journals (Sweden)

Tadahide Furuno

2013-08-01

Full Text Available Nano vectors are useful tools to deliver foreign DNAs, oligonucleotides, and small interfering double-stranded RNAs (siRNAs into mammalian cells with gene transfection and gene regulation. In such experiments we have found the liposomes with a biosurfacant mannosylerythriol lipid (MEL-A are useful because of their high transfer efficiency, and their unique mechanism to transfer genes to target cells with the lowest toxicity. In the present review we will describe our current work, which may contribute to the great advance of gene transfer to target cells and gene regulations. For more than two decades, the liposome technologies have changed dramatically and various methods have been proposed in the fields of biochemistry, cell biology, biotechnology, and so on. In addition, they were towards to pharmaceutics and clinical applications. The liposome technologies were expected to use gene therapy, however, they have not reached a requested goal as of yet. In the present paper we would like to present an approach using a biosurfactant, MEL-A, which is a surface-active compound produced by microorganisms growing on water-insoluble substrates and increases efficiency in gene transfection. The present work shows new transfection agents based on liposomes containing biosurfactant MEL-A.

A Case of Myopathy, Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS) Syndrome with Intracardiac Thrombus [corrected].

Science.gov (United States)

Joo, Jung-Chul; Seol, Myung Do; Yoon, Jin Won; Lee, Young Soo; Kim, Dong-Keun; Choi, Yong Hoon; Ahn, Hyo Seong; Cho, Wook Hyun

2013-03-01

Myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) is a multisystem clinical syndrome manifested by mitochondrial myopathy, encephalopathy, lactic acidosis and recurrent stroke-like episodes. A 27-year-old female with MELAS syndrome presented with cerebral infarction. Echocardiography revealed a thrombus attached to the apex of the hypertrophied left ventricle, with decreased systolic function. The embolism of the intracardiac thrombus might have been the cause of stroke. There should be more consideration given to the increased possibility of intracardiac thrombus formation when a MELAS patient with cardiac involvement is encountered.

MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis, Stroke) – a Diagnosis Not to be Missed

LENUS (Irish Health Repository)

Quinn, NM

2016-09-01

MELAS is a rare mitochondrial disorder. We report two cases in Irish males where the characteristics were evident, but the diagnosis not made for a considerable period of time. In one of the cases the symptoms were presumed secondary to prematurity. In the other the symptoms were presumed secondary to epilepsy and he had three respiratory arrests secondary to benzodiazepine administration. This report wishes to highlight MELAS as a differential diagnosis in paediatric patients who present with stroke.

Diffusion and Perfusion Characteristics of MELAS (Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-Like Episode) in Thirteen Patients

International Nuclear Information System (INIS)

Kim, Ji Hye; Jeon, Tae Yeon; Eo, Hong; Yoo, So Young; Lim, Myung Kwan; Rha, Jung Ho; Shu, Chang Hae

2011-01-01

We analyzed the diffusion and perfusion characteristics of acute MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episode) lesions in a large series to investigate the controversial changes of the apparent diffusion coefficient (ADC) that were reported in prior studies. We analyzed 44 newly appearing lesions during 28 stroke-like episodes in 13 patients with MELAS. We performed a visual assessment of the MR images including the ADC and perfusion maps, comparison of the ADC between the normal and abnormal areas, comparison of % ADC between the 44 MELAS lesions and the 30 acute ischemic infarcts. In addition, the patterns of evolution on follow-up MR images were analyzed. Decreased, increased, and normal ADCs were noted in 16 (36%), 16 (36%), and 12 (27%) lesions, respectively. The mean % ADC was 102 ± 40.9% in the MELAS and 64 ± 17.8% in the acute vascular infarcts (p < 0.001), while perfusion imaging demonstrated hyper-perfusion in six acute MELAS lesions. On follow-up images, resolution, progression, and tissue loss were noted in 10, 4, and 17 lesions, respectively. The cytotoxic edema gradually evolves following an acute stroke-like episode in patients with MELAS, and this may overlap with hyper-perfusion and vasogenic edema. The edematous swelling may be reversible or it may evolve to encephalomalacia, suggesting irreversible damage

Diffusion and Perfusion Characteristics of MELAS (Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-Like Episode) in Thirteen Patients

Science.gov (United States)

Kim, Ji Hye; Jeon, Tae Yeon; Rha, Jung Ho; Eo, Hong; Yoo, So-Young; Shu, Chang Hae

2011-01-01

Objective We analyzed the diffusion and perfusion characteristics of acute MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episode) lesions in a large series to investigate the controversial changes of the apparent diffusion coefficient (ADC) that were reported in prior studies. Materials and Methods We analyzed 44 newly appearing lesions during 28 stroke-like episodes in 13 patients with MELAS. We performed a visual assessment of the MR images including the ADC and perfusion maps, comparison of the ADC between the normal and abnormal areas, comparison of % ADC between the 44 MELAS lesions and the 30 acute ischemic infarcts. In addition, the patterns of evolution on follow-up MR images were analyzed. Results Decreased, increased, and normal ADCs were noted in 16 (36%), 16 (36%), and 12 (27%) lesions, respectively. The mean % ADC was 102 ± 40.9% in the MELAS and 64 ± 17.8% in the acute vascular infarcts (p MELAS lesions. On follow-up images, resolution, progression, and tissue loss were noted in 10, 4, and 17 lesions, respectively. Conclusion The cytotoxic edema gradually evolves following an acute stroke-like episode in patients with MELAS, and this may overlap with hyper-perfusion and vasogenic edema. The edematous swelling may be reversible or it may evolve to encephalomalacia, suggesting irreversible damage. PMID:21228936

MELAS syndrome and cardiomyopathy: linking mitochondrial function to heart failure pathogenesis.

Science.gov (United States)

Hsu, Ying-Han R; Yogasundaram, Haran; Parajuli, Nirmal; Valtuille, Lucas; Sergi, Consolato; Oudit, Gavin Y

2016-01-01

Heart failure remains an important clinical burden, and mitochondrial dysfunction plays a key role in its pathogenesis. The heart has a high metabolic demand, and mitochondrial function is a key determinant of myocardial performance. In mitochondrial disorders, hypertrophic remodeling is the early pattern of cardiomyopathy with progression to dilated cardiomyopathy, conduction defects and ventricular pre-excitation occurring in a significant proportion of patients. Cardiac dysfunction occurs in approximately a third of patients with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome, a stereotypical example of a mitochondrial disorder leading to a cardiomyopathy. We performed unique comparative ultrastructural and gene expression in a MELAS heart compared with non-failing controls. Our results showed a remarkable increase in mitochondrial inclusions and increased abnormal mitochondria in MELAS cardiomyopathy coupled with variable sarcomere thickening, heterogeneous distribution of affected cardiomyocytes and a greater elevation in the expression of disease markers. Investigation and management of patients with mitochondrial cardiomyopathy should follow the well-described contemporary heart failure clinical practice guidelines and include an important role of medical and device therapies. Directed metabolic therapy is lacking, but current research strategies are dedicated toward improving mitochondrial function in patients with mitochondrial disorders.

Quantitative measurement of cerebral oxygen extraction fraction using MRI in patients with MELAS.

Directory of Open Access Journals (Sweden)

Lei Yu

Full Text Available OBJECTIVE: To quantify the cerebral OEF at different phases of stroke-like episodes in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS by using MRI. METHODS: We recruited 32 patients with MELAS confirmed by gene analysis. Conventional MRI scanning, as well as functional MRI including arterial spin labeling and oxygen extraction fraction imaging, was undertaken to obtain the pathological and metabolic information of the brains at different stages of stroke-like episodes in patients. A total of 16 MRI examinations at the acute and subacute phase and 19 examinations at the interictal phase were performed. In addition, 24 healthy volunteers were recruited for control subjects. Six regions of interest were placed in the anterior, middle, and posterior parts of the bilateral hemispheres to measure the OEF of the brain or the lesions. RESULTS: OEF was reduced significantly in brains of patients at both the acute and subacute phase (0.266 ± 0.026 and at the interictal phase (0.295 ± 0.009, compared with normal controls (0.316 ± 0.025. In the brains at the acute and subacute phase of the episode, 13 ROIs were prescribed on the stroke-like lesions, which showed decreased OEF compared with the contralateral spared brain regions. Increased blood flow was revealed in the stroke-like lesions at the acute and subacute phase, which was confined to the lesions. CONCLUSION: MRI can quantitatively show changes in OEF at different phases of stroke-like episodes. The utilization of oxygen in the brain seems to be reduced more severely after the onset of episodes in MELAS, especially for those brain tissues involved in the episodes.

Restoration of impaired nitric oxide production in MELAS syndrome with citrulline and arginine supplementation.

Science.gov (United States)

El-Hattab, Ayman W; Hsu, Jean W; Emrick, Lisa T; Wong, Lee-Jun C; Craigen, William J; Jahoor, Farook; Scaglia, Fernando

2012-04-01

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most common mitochondrial disorders. Although the pathogenesis of stroke-like episodes remains unclear, it has been suggested that mitochondrial proliferation may result in endothelial dysfunction and decreased nitric oxide (NO) availability leading to cerebral ischemic events. This study aimed to assess NO production in subjects with MELAS syndrome and the effect of the NO precursors arginine and citrulline. Using stable isotope infusion techniques, we assessed arginine, citrulline, and NO metabolism in control subjects and subjects with MELAS syndrome before and after arginine or citrulline supplementation. The results showed that subjects with MELAS had lower NO synthesis rate associated with reduced citrulline flux, de novo arginine synthesis rate, and plasma arginine and citrulline concentrations, and higher plasma asymmetric dimethylarginine (ADMA) concentration and arginine clearance. We conclude that the observed impaired NO production is due to multiple factors including elevated ADMA, higher arginine clearance, and, most importantly, decreased de novo arginine synthesis secondary to decreased citrulline availability. Arginine and, to a greater extent, citrulline supplementation increased the de novo arginine synthesis rate, the plasma concentrations and flux of arginine and citrulline, and NO production. De novo arginine synthesis increased markedly with citrulline supplementation, explaining the superior efficacy of citrulline in increasing NO production. The improvement in NO production with arginine or citrulline supplementation supports their use in MELAS and suggests that citrulline may have a better therapeutic effect than arginine. These findings can have a broader relevance for other disorders marked by perturbations in NO metabolism. Copyright © 2012 Elsevier Inc. All rights reserved.

Mitochondrial encephalopathy, lactic acidosis, and strokelike episodes: basic concepts, clinical phenotype, and therapeutic management of MELAS syndrome.

Science.gov (United States)

Sproule, Douglas M; Kaufmann, Petra

2008-10-01

Since the initial description almost 25 years ago, the syndrome of mitochondrial encephalopathy, lactic acidosis, and strokelike episodes (MELAS) has been a useful model to study the complex interplay of factors that define mitochondrial disease. This syndrome, most commonly caused by an A-to-G transition mutation at position 3243 of the mitochondrial genome, is typified by characteristic neurological manifestations including seizures, encephalopathy, and strokelike episodes, as well as other frequent secondary manifestations including short stature, cognitive impairment, migraines, depression, cardiomyopathy, cardiac conduction defects, and diabetes mellitus. In this review, we discuss the history, pathogenesis, clinical features, and diagnostic and management strategies of mitochondrial disease in general and of MELAS in particular. We explore features of mitochondrial genetics, including the concepts of heteroplasmy, mitotic segregation, and threshold effect, as a basis for understanding the variability and complicated inheritance patterns seen with this group of diseases. We also describe systemic manifestations of MELAS-associated mutations, including cardiac, renal, endocrine, gastrointestinal, and endothelial abnormalities and pathology, as well as the hypothetical role of derangements to COX enzymatic function in driving the unique pathology and clinical manifestations of MELAS. Although therapeutic options for MELAS and other mitochondrial diseases remain limited, and recent trials have been disappointing, we also consider current and potential therapeutic modalities.

Successful left hemihepatectomy and perioperative management of a patient with biliary cystadenocarcinoma, complicated with MELAS syndrome: report of a case.

Science.gov (United States)

Ohno, Ayami; Mori, Akira; Doi, Ryuichiro; Yonenaga, Yoshikuni; Asano, Noboru; Uemoto, Shinji

2010-09-01

Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like syndrome (MELAS) is a rare, fetal disease caused by a mutation in mitochondrial DNA that leads to impaired oxidative metabolism in skeletal muscle, the central nervous system, and liver function. This report presents the case of a 50-year-old woman with biliary cystadenocarcinoma complicated by MELAS who underwent a successful left hemihepatectomy. In this case, the diagnostic key for the malignant tumor was an (18)F-fluorodeoxyglucose positron emission tomography study, which was useful even in a patient with MELAS, which causes abnormal glucose metabolism. The perioperative management of such patients includes special precautions to prevent lactic acidosis and deterioration of the reserved liver function after a hepatectomy, since the mitochondrial function in MELAS patients is abnormal. The patient in this report has remained free of liver dysfunctions and cancer recurrence for 2 years following the hepatectomy. This is the first report of a successful major hepatectomy for a patient with MELAS.

L-Arginine Affects Aerobic Capacity and Muscle Metabolism in MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis and Stroke-Like Episodes Syndrome.

Directory of Open Access Journals (Sweden)

Lance H Rodan

Full Text Available To study the effects of L-arginine (L-Arg on total body aerobic capacity and muscle metabolism as assessed by (31Phosphorus Magnetic Resonance Spectroscopy ((31P-MRS in patients with MELAS (Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like episodes syndrome.We performed a case control study in 3 MELAS siblings (m.3243A>G tRNA(leu(UUR in MTTL1 gene with different % blood mutant mtDNA to evaluate total body maximal aerobic capacity (VO(2peak using graded cycle ergometry and muscle metabolism using 31P-MRS. We then ran a clinical trial pilot study in MELAS sibs to assess response of these parameters to single dose and a 6-week steady-state trial of oral L-Arginine.At baseline (no L-Arg, MELAS had lower serum Arg (p = 0.001. On 3(1P-MRS muscle at rest, MELAS subjects had increased phosphocreatine (PCr (p = 0.05, decreased ATP (p = 0.018, and decreased intracellular Mg(2+ (p = 0.0002 when compared to matched controls. With L-arginine therapy, the following trends were noted in MELAS siblings on cycle ergometry: (1 increase in mean % maximum work at anaerobic threshold (AT (2 increase in % maximum heart rate at AT (3 small increase in VO(2peak. On (31P-MRS the following mean trends were noted: (1 A blunted decrease in pH after exercise (less acidosis (2 increase in Pi/PCr ratio (ADP suggesting increased work capacity (3 a faster half time of PCr recovery (marker of mitochondrial activity following 5 minutes of moderate intensity exercise (4 increase in torque.These results suggest an improvement in aerobic capacity and muscle metabolism in MELAS subjects in response to supplementation with L-Arg. Intramyocellular hypomagnesemia is a novel finding that warrants further study.Class III evidence that L-arginine improves aerobic capacity and muscle metabolism in MELAS subjects.ClinicalTrials.gov NCT01603446.

L-Arginine Affects Aerobic Capacity and Muscle Metabolism in MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis and Stroke-Like Episodes) Syndrome.

Science.gov (United States)

Rodan, Lance H; Wells, Greg D; Banks, Laura; Thompson, Sara; Schneiderman, Jane E; Tein, Ingrid

2015-01-01

To study the effects of L-arginine (L-Arg) on total body aerobic capacity and muscle metabolism as assessed by (31)Phosphorus Magnetic Resonance Spectroscopy ((31)P-MRS) in patients with MELAS (Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like episodes) syndrome. We performed a case control study in 3 MELAS siblings (m.3243A>G tRNA(leu(UUR)) in MTTL1 gene) with different % blood mutant mtDNA to evaluate total body maximal aerobic capacity (VO(2peak)) using graded cycle ergometry and muscle metabolism using 31P-MRS. We then ran a clinical trial pilot study in MELAS sibs to assess response of these parameters to single dose and a 6-week steady-state trial of oral L-Arginine. At baseline (no L-Arg), MELAS had lower serum Arg (p = 0.001). On 3(1)P-MRS muscle at rest, MELAS subjects had increased phosphocreatine (PCr) (p = 0.05), decreased ATP (p = 0.018), and decreased intracellular Mg(2+) (p = 0.0002) when compared to matched controls. With L-arginine therapy, the following trends were noted in MELAS siblings on cycle ergometry: (1) increase in mean % maximum work at anaerobic threshold (AT) (2) increase in % maximum heart rate at AT (3) small increase in VO(2peak). On (31)P-MRS the following mean trends were noted: (1) A blunted decrease in pH after exercise (less acidosis) (2) increase in Pi/PCr ratio (ADP) suggesting increased work capacity (3) a faster half time of PCr recovery (marker of mitochondrial activity) following 5 minutes of moderate intensity exercise (4) increase in torque. These results suggest an improvement in aerobic capacity and muscle metabolism in MELAS subjects in response to supplementation with L-Arg. Intramyocellular hypomagnesemia is a novel finding that warrants further study. Class III evidence that L-arginine improves aerobic capacity and muscle metabolism in MELAS subjects. ClinicalTrials.gov NCT01603446.

Atypical Strokes in a Young African American Male: A Case of Mitochondrial Encephalopathy Lactic Acidosis and Stroke-Like Episodes (MELAS) Syndrome

Science.gov (United States)

Sanchez, Jully M.; Tan, Judy Ann; Farmakiotis, Dimitrios; Aggarwal, Vikas

2011-01-01

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare but important cause of stroke-like symptoms which can often be missed Thambisetty and Newman 2004. We describe a case of a young male presenting with stroke-like episodes, later diagnosed with MELAS in an attempt to improve the understanding about diagnosing MELAS in the appropriate clinical context. PMID:21789268

Late onset MELAS with m.3243A > G mutation and its association with aneurysm formation.

Science.gov (United States)

Zhu, Kun; Li, Shuang; Chen, Huan; Wang, Yao; Yu, Miao; Wang, Hongyan; Zhao, Weijie; Cao, Yunpeng

2017-08-01

We reported a 53-year-old with late-onset mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) accompanied by aneurysm and large vessel dilations. Most studies have focused on microangiopathy causing stroke-like episodes. We report a case to describe large vessel involvement in clinical considerations, and possible mechanisms of aneurysm formation. We recommended regular angiographic examination for patients with MELAS.

Cervecería Artesanal, Mela`s Craft Beer : trabajo de Grado en emprendimiento

OpenAIRE

Manotas, Eduardo Alejandro

2017-01-01

En Colombia, el consumo de cerveza viene creciendo a pasos agigantados, nada más en los últimos 4 años pasamos de ser el octavo país en consumo per cápita de cerveza en Latinoamérica con 45 Litros a ser el tercero con un consumo de 58Lt. Al año. EL crecimiento de Bavaria se ha sostenido alrededor de los 18 puntos porcentuales y el de la cerveza artesanal esta aproximadamente en un 40% año a año. Mela´s Craft Beer nace bajo la necesidad de traer al país cerveza de calidad mundial como no ex...

Validating tyrosinase homologue MelA as a photoacoustic reporter gene for imaging Escherichia coli

Science.gov (United States)

Paproski, Robert J.; Li, Yan; Barber, Quinn; Lewis, John D.; Campbell, Robert; Zemp, Roger

2015-03-01

Antibiotic drug resistance is a major worldwide issue. Development of new therapies against pathogenic bacteria requires appropriate research tools for replicating and characterizing infections. Previously fluorescence and bioluminescence modalities have been used to image infectious burden in animal models but scattering significantly limits imaging depth and resolution. We hypothesize that photoacoustic imaging, which has improved depth-toresolution ratio, could be useful for visualizing MelA-expressing bacteria since MelA is a bacterial tyrosinase homologue involved in melanin production. Using an inducible expression system, E. coli expressing MelA were visibly black in liquid culture. Phosphate buffered saline (PBS), MelA-expressing bacteria (at different dilutions in PBS), and chicken embryo blood were injected in plastic tubes which were imaged using a VisualSonics Vevo LAZR system. Photoacoustic imaging at 6 different wavelengths (680, 700, 750, 800, 850 and 900nm) enabled spectral de-mixing to distinguish melanin signals from blood. The signal to noise ratio of 9x diluted MelA bacteria was 55, suggesting that ~20 bacteria cells could be detected with our system. When MelA bacteria were injected as a 100 μL bolus into a chicken embryo, photoacoustic signals from deoxy- and oxy- hemoglobin as well as MelA-expressing bacteria could be separated and overlaid on an ultrasound image, allowing visualization of the bacterial location. Photoacoustic imaging may be a useful tool for visualizing bacterial infections and further work incorporating photoacoustic reporters into infectious bacterial strains is warranted.

Disturbance-specific social responses in long-finned pilot whales, Globicephala melas

NARCIS (Netherlands)

Visser, F.; Curé, C.; Kvadsheim, P.H.; Lam, F.P.A.; Tyack, P.L.; Miller, P.J.O.

2016-01-01

Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: Tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of

Disturbance-specific social responses in long-finned pilot whales, Globicephala melas

Science.gov (United States)

Visser, Fleur; Curé, Charlotte; Kvadsheim, Petter H.; Lam, Frans-Peter A.; Tyack, Peter L.; Miller, Patrick J. O.

2016-06-01

Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of tagged individuals were recorded along with the social behaviour of their groups. All three disturbance types resulted in larger group sizes, increasing social cohesion during disturbance. However, the nature and magnitude of other responses differed between disturbance types. Tagging effort resulted in a clear increase in synchrony and a tendency to reduce surface logging and to become silent (21% of cases), whereas pilot whales increased surface resting during sonar exposure. Killer whale sounds elicited increased calling rates and the aggregation of multiple groups, which approached the sound source together. This behaviour appears to represent a mobbing response, a likely adaptive social defence against predators or competitors. All observed response-tactics would reduce risk of loss of group coordination, suggesting that, in social pilot whales, this could drive behavioural responses to disturbance. However, the behavioural means used to achieve social coordination depends upon other considerations, which are disturbance-specific.

Regression of stroke-like lesions in MELAS-syndrome after seizure control.

Science.gov (United States)

Finsterer, Josef; Barton, Peter

2010-12-01

There are some indications that seizure activity promotes the development of stroke-like episodes, or vice versa, in patients with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome or other syndromic mitochondrial disorders. A 41-year-old Caucasian female with MELAS syndrome, presenting with short stature, microcytic anaemia, increased blood-sedimentation rate, myopathy, hyper-gammaglobulinaemia, an iron-metabolism defect, migraine-like headaches, and stroke-like episodes, developed complex partial and generalised seizures at age 32 years. Valproic acid was ineffective but after switching to lamotrigine and lorazepam, she became seizure-free for five years and stroke-like episodes did not recur. Cerebral MRI initially showed enhanced gyral thickening and a non-enhanced T2-hyperintensity over the left parieto-temporo-occipital white matter and cortex and enhanced caudate heads. After two years without seizures, the non-enhanced hyperintense parieto-temporo-occipital lesion had disappeared, being attributed to consequent seizure control. The caudate heads, however, remained hyperintense throughout the observational period. This case indicates that adequate seizure control in a patient with MELAS syndrome may prevent the recurrence of stroke-like episodes and may result in the disappearance of stroke-like lesions on MRI.

A whole mitochondrial genome screening in a MELAS patient: A novel mitochondrial tRNAVal mutation

International Nuclear Information System (INIS)

Mezghani, Najla; Mnif, Mouna; Kacem, Maha; Mkaouar-Rebai, Emna; Hadj Salem, Ikhlass; Kallel, Nozha; Charfi, Nadia; Abid, Mohamed; Fakhfakh, Faiza

2011-01-01

Highlights: → We report a young Tunisian patient with clinical features of MELAS syndrome. → Reported mitochondrial mutations were absent after a mutational screening of the whole mtDNA. → We described a novel m.1640A>G mutation in the tRNA Val gene which was absent in 150 controls. → Mitochondrial deletions and POLG1 gene mutations were absent. → The m.1640A>G mutation could be associated to MELAS syndrome. -- Abstract: Mitochondrial encephalopathy, lactic acidosis and strokelike episodes (MELAS) syndrome is a mitochondrial disorder characterized by a wide variety of clinical presentations and a multisystemic organ involvement. In this study, we report a Tunisian girl with clinical features of MELAS syndrome who was negative for the common m.3243A>G mutation, but also for the reported mitochondrial DNA (mtDNA) mutations and deletions. Screening of the entire mtDNA genome showed several known mitochondrial variants besides to a novel transition m.1640A>G affecting a wobble adenine in the anticodon stem region of the tRNA Val . This nucleotide was conserved and it was absent in 150 controls suggesting its pathogenicity. In addition, no mutations were found in the nuclear polymerase gamma-1 gene (POLG1). These results suggest further investigation nuclear genes encoding proteins responsible for stability and structural components of the mtDNA or to the oxidative phosphorylation machinery to explain the phenotypic variability in the studied family.

[Characteristics of anesthesia in patients with MELAS syndrome: Case report of anesthesia in video-assisted thoracoscopy].

Science.gov (United States)

Haas, A; Wappler, F

2015-10-01

The mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome is a disease triggered by a disorder in energy production within mitochondria. The cause of this syndrome is a mutation in the mitochondrial DNA where in 80% of cases an A-to-G mutation is present at nucleotide 3243 and with a prevalence of 18.4/100,000 in the population. Predominantly affected are organ systems with a high energy metabolism, such as the heart, brain and musculature. During the premedication visit a thorough patient history and examination with respect to neurological impairments must be carried out. Epilepsy and the appropriate permanent medication lead to possible alterations in effectiveness of anesthetics and muscle relaxants which are difficult to predict. An extensive patient cardiac history and a preoperative electrocardiogram (ECG) for an appraisal of possible disorders in the cardiac conduction system and when necessary extended cardiac diagnostics, are recommended. The monitoring must be adapted depending on the functional limitations and the forthcoming intervention and when necessary a postoperative surveillance in an intensive care unit should be initiated. Knowledge of the special features of MELAS syndrome in association with a consideration of the characteristics of anesthesia in MELAS patients and an individually adapted intensified perioperative surveillance, can contribute to a reduction in perioperative morbidity in patients suffering from MELAS syndrome.

Adult-onset of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome presenting as acute meningoencephalitis: a case report.

Science.gov (United States)

Hsu, Yu-Chuan; Yang, Fu-Chi; Perng, Cherng-Lih; Tso, An-Chen; Wong, Lee-Jun C; Hsu, Chang-Hung

2012-09-01

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare mitochondrial disorder with a wide range of multisystemic symptoms. Epileptic seizures are common features of both MELAS and meningoencephalitis and are typically treated with anticonvulsants. To provide the reader with a better understanding of MELAS and the adverse effects of valproic acid. A 47-year-old man with a history of diabetes, hearing loss, sinusitis, and otitis media was brought to our emergency department due to acute onset of fever, headache, generalized seizure, and agitation. Because acute meningoencephalitis was suspected, the patient was treated with antibiotics on an empirical basis. The seizure activity was aggravated by valproic acid and abated after its discontinuation. MELAS was suspected and the diagnosis was confirmed by the presence of a nucleotide 3243 A→G mutation in the mitochondrial DNA. Detailed history-taking and systematic review help emergency physicians differentiate MELAS from meningoencephalitis in patients with the common presentation of epileptic seizures. Use of valproic acid to treat epilepsy in patients suspected of having mitochondrial disease should be avoided. Underlying mitochondrial disease should be suspected if seizure activity worsens with valproic acid therapy. Copyright © 2012 Elsevier Inc. All rights reserved.

Increased cerebral blood flow in MELAS shown by Tc-99m HMPAO brain SPECT

International Nuclear Information System (INIS)

Peng, N.J.; Tsay, D.G.; Liu, R.S.; Li, J.Y.; Kong, K.W.; Kwok, C.G.; Strauss, H.W.

2000-01-01

We report cerebral SPECT studies on two siblings with the syndrome of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). Tc-99m HMPAO brain SPECT was performed 8, 19 and 30 days after a stroke-like episode in one case and 10 days after a stroke-like episode, 6 h after a partial seizure and as a follow-up study in the other. Increased blood flow was seen in both these patients with stroke-like episodes due to MELAS. The cause of the increased blood flow is uncertain, but it may be related to the decreased pH created by local increase in lactic acid. (orig.)

Unique presentation of LHON/MELAS overlap syndrome caused by m.13046T>C in MTND5.

Science.gov (United States)

Kolarova, Hana; Liskova, Petra; Tesarova, Marketa; Kucerova Vidrova, Vendula; Forgac, Martin; Zamecnik, Josef; Hansikova, Hana; Honzik, Tomas

2016-12-01

Leber hereditary optic neuropathy (LHON) and mitochondrial encephalopathy, myopathy, lactic acidosis and stroke-like episodes (MELAS) syndromes are mitochondrially inherited disorders characterized by acute visual failure and variable multiorgan system presentation, respectively. A 12-year-old girl with otherwise unremarkable medical history presented with abrupt, painless loss of vision. Over the next few months, she developed moderate sensorineural hearing loss, vertigo, migraines, anhedonia and thyroiditis. Ocular examination confirmed bilateral optic nerve atrophy. Metabolic workup documented elevated cerebrospinal fluid lactate. Initial genetic analyses excluded the three most common LHON mutations. Subsequently, Sanger sequencing of the entire mitochondrial DNA (mtDNA) genome was performed. Whole mtDNA sequencing revealed a pathogenic heteroplasmic mutation m.13046T>C in MTND5 encoding the ND5 subunit of complex I. This particular variant has previously been described in a single case report of MELAS/Leigh syndrome (subacute necrotizing encephalopathy). Based on the constellation of clinical symptoms in our patient, we diagnose the condition as LHON/MELAS overlap syndrome. We describe a unique presentation of LHON/MELAS overlap syndrome resulting from a m.13046T>C mutation in a 12-year-old girl. In patients with sudden vision loss in which three of the most prevalent LHON mitochondrial mutations have been ruled out, molecular genetic examination should be extended to other mtDNA-encoded subunits of MTND5 complex I. Furthermore, atypical clinical presentations must be considered, even in well-described phenotypes.

Anesthetic Management of Mitochondrial Encephalopathy With Lactic Acidosis and Stroke-Like Episodes (MELAS Syndrome) in a High-Risk Pregnancy: A Case Report.

Science.gov (United States)

Bell, Josh D; Higgie, Kushlin; Joshi, Mital; Rucker, Joshua; Farzi, Sahar; Siddiqui, Naveed

2017-07-15

MELAS syndrome (mitochondrial encephalopathy, lactic acidosis, and stroke-like symptoms) is a rare and complex mitochondrial disorder. We present the in-hospital course of a 36-year-old gravida 2, para 0 with MELAS syndrome and severe preeclampsia, complicated by hyponatremia, hyperkalemia, and diabetes. A retained placenta with postpartum hemorrhage required urgent instrumental delivery under spinal anesthesia, transfusion, and intensive care unit admission for pulmonary edema, effusions, and atelectasis. Postpartum endometritis and sepsis also were encountered. This is to our knowledge the first case report of obstetric complications in MELAS syndrome and highlights the salient metabolic sequelae of this syndrome.

Audiological manifestations in mitochondrial encephalomyopathy lactic acidosis and stroke like episodes (MELAS) syndrome.

Science.gov (United States)

Vandana, V P; Bindu, Parayil Sankaran; Sonam, Kothari; Govindaraj, Periyasamy; Taly, Arun B; Gayathri, Narayanappa; Chiplunkar, Shwetha; Govindaraju, Chikkanna; Arvinda, H R; Nagappa, Madhu; Sinha, Sanjib; Thangaraj, Kumarasamy

2016-09-01

Reports of audiological manifestations in specific subgroups of mitochondrial disorders are limited. This study aims to describe the audiological findings in patients with MELAS syndrome and m.3243A>G mutation. Audiological evaluation was carried out in eight patients with confirmed MELAS syndrome and m.3243A>G mutation. The evaluation included a complete neurological evaluation, pure tone audiometry (n=8), otoacoustic emissions (n=8) and brainstem evoked response audiometry (n=6), magnetic resonance imaging (n=8) and muscle biospy (n=6). Eight patients (Age range: 5-45 years; M:F-1:3) including six children and two adults underwent formal audiological evaluation. Five patients had hearing loss; of these two had "subclinical hearing loss", one had moderate and two had severe hearing loss. The abnormalities included abnormal audiometry (n=5), otoacoustic emission testing (n=7) and absent brainstem auditory evoked responses (n=1). The findings were suggestive of cochlear involvement in four and retrocochlear in one. This study shows that hearing loss of both cochlear and retrocochlear origin occurs in patients with MELAS and may be subclinical. Early referrals for audiological evaluation is warranted to recognize the subclinical hearing loss in these patients. The therapeutic implications include early interventions in the form of hearing aids, cochlear implants and cautioning the physicians for avoidance of aminoglycosides. Copyright © 2016 Elsevier B.V. All rights reserved.

[Mutism and acute behavioral disorders revealing MELAS syndrome].

Science.gov (United States)

Coomans, H; Barroso, B; Bertandeau, E; Bonnan, M; Dakar, A; Demasles, S; Garraud, S; Krim, E; Martin-Négrier, M-L

2011-11-01

MELAS syndrome (mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes) is a rare genetic mitochondrial disease which can cause cerebral (cerebrovascular accident, migraine, mental deterioration..), sensorial (bilateral symmetrical deafness) and peripheral (muscular involvement, neuropathy) disorders potentially associated with diabetes, renal or cardiac disorders, or growth retardation. Eighty percent of the patients have the 3243 A>G mutation in the leucine RNA transfer gene. Clinical manifestations leading to discovery of the mutation can be extremely varied, affecting patients of different age groups. We report the case of a 49-year-old man who presented acute fits of confusion followed by mutism and praxic disorders. History taking revealed recently diagnosed type 2 diabetes, axonal neuropathy, and bilateral symmetrical deafness requiring hearing aids. The initial MRI showed FLAIR sequences with bi-parietal abnormalities, no signs of recent stroke on the DW/B10000 sequences, and basal ganglia calcifications. Blood tests and morphological findings ruled out a vascular origin. Search for lactic acidosis remained constantly negative in blood samples despite positive cerebrospinal fluid samples (N×3). The 3243 A>G mitochondrial DNA mutation was identified. The neuropsychological evaluation revealed a serious dysexecutive syndrome with a major impact on the patient's self sufficiency. Neurocognitive disorders are not common in MELAS syndrome. Brain MRI results and the presence of extra-neurological signs can be helpful for diagnosis. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

A whole mitochondrial genome screening in a MELAS patient: A novel mitochondrial tRNA{sup Val} mutation

Energy Technology Data Exchange (ETDEWEB)

Mezghani, Najla [Laboratoire de Genetique Moleculaire Humaine, Faculte de Medecine de Sfax, Universite de Sfax (Tunisia); Mnif, Mouna [Service d' endocrinologie, C.H.U. Habib Bourguiba de Sfax (Tunisia); Kacem, Maha [Service de Medecine interne, C.H.U. Fattouma Bourguiba de Monastir (Tunisia); Mkaouar-Rebai, Emna, E-mail: emna_mkaouar@mail2world.com [Laboratoire de Genetique Moleculaire Humaine, Faculte de Medecine de Sfax, Universite de Sfax (Tunisia); Hadj Salem, Ikhlass [Laboratoire de Genetique Moleculaire Humaine, Faculte de Medecine de Sfax, Universite de Sfax (Tunisia); Kallel, Nozha; Charfi, Nadia; Abid, Mohamed [Service d' endocrinologie, C.H.U. Habib Bourguiba de Sfax (Tunisia); Fakhfakh, Faiza [Laboratoire de Genetique Moleculaire Humaine, Faculte de Medecine de Sfax, Universite de Sfax (Tunisia)

2011-04-22

Highlights: {yields} We report a young Tunisian patient with clinical features of MELAS syndrome. {yields} Reported mitochondrial mutations were absent after a mutational screening of the whole mtDNA. {yields} We described a novel m.1640A>G mutation in the tRNA{sup Val} gene which was absent in 150 controls. {yields} Mitochondrial deletions and POLG1 gene mutations were absent. {yields} The m.1640A>G mutation could be associated to MELAS syndrome. -- Abstract: Mitochondrial encephalopathy, lactic acidosis and strokelike episodes (MELAS) syndrome is a mitochondrial disorder characterized by a wide variety of clinical presentations and a multisystemic organ involvement. In this study, we report a Tunisian girl with clinical features of MELAS syndrome who was negative for the common m.3243A>G mutation, but also for the reported mitochondrial DNA (mtDNA) mutations and deletions. Screening of the entire mtDNA genome showed several known mitochondrial variants besides to a novel transition m.1640A>G affecting a wobble adenine in the anticodon stem region of the tRNA{sup Val}. This nucleotide was conserved and it was absent in 150 controls suggesting its pathogenicity. In addition, no mutations were found in the nuclear polymerase gamma-1 gene (POLG1). These results suggest further investigation nuclear genes encoding proteins responsible for stability and structural components of the mtDNA or to the oxidative phosphorylation machinery to explain the phenotypic variability in the studied family.

MERRF/MELAS overlap syndrome due to the m.3291T>C mutation.

Science.gov (United States)

Liu, Kaiming; Zhao, Hui; Ji, Kunqian; Yan, Chuanzhu

2014-03-01

We report the case of a 19-year-old Chinese female harboring the m.3291T>C mutation in the MT-TL1 gene encoding the mitochondrial transfer RNA for leucine. She presented with a complex phenotype characterized by progressive cerebellar ataxia, frequent myoclonus seizures, recurrent stroke-like episodes, migraine-like headaches with nausea and vomiting, and elevated resting lactate blood level. It is known that the myoclonus epilepsy with ragged-red fibers (MERRF) is characterized by cerebellar ataxia and myoclonus epilepsy, while that the mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is characterized by recurrent stroke-like episodes, migraine-like headaches, and elevated resting lactate blood level. So the patient's clinical manifestations suggest the presence of a MERRF/MELAS overlap syndrome. Muscle biopsy of the patient showed the presence of numerous scattered ragged-red fibers, some cytochrome c oxidase-deficient fibers, and several strongly succinate dehygrogenase-reactive vessels, suggestive of a mitochondrial disorder. Direct sequencing of the complete mitochondrial genome of the proband revealed no mutations other than the T-to-C transition at nucleotide position 3291. Restriction fragment length polymorphism analysis of the proband and her family revealed maternal inheritance of the mutation in a heteroplasmic manner. The analysis of aerobic respiration and glycolysis demonstrated that the fibroblasts from the patient had mitochondrial dysfunction. Our results suggest that the m.3291T>C is pathogenic. This study is the first to describe the m.3291T>C mutation in association with the MERRF/MELAS overlap syndrome.

[l-arginine efficiency in MELAS syndrome. A case report].

Science.gov (United States)

Moutaouakil, F; El Otmani, H; Fadel, H; Sefrioui, F; Slassi, I

2009-05-01

Mitochondrial encephalomyopathy lactic acidosis and stoke-like episodes (MELAS) is a rare neurodegenerative disease caused by mutations of mitochondrial DNA. We report the case of a 12-year-old child with MELAS syndrome who presented with recurrent migraine-like headache and sudden blindness suggesting stroke-like episodes. Furthermore, he developed progressive muscular impairment with bilateral hearing loss. Serum lactate and pyruvate levels were elevated and the muscle biopsy showed an aspect of red-ragged fibers with Gomori trichrome. Brain imaging showed calcifications of basal ganglia on the CT scan and a parieto-occipital high signal on diffusion-weighted MRI. A genetic analysis was not performed but the presence of hearing loss in the patient's mother was suggestive of maternal transmission. Stroke-like episodes in the form of migraine-like headache and blindness were the patient's major complaint and did not improve despite analgesic drugs. After oral administration of l-arginine at the dose of 0.4mg/kg per day, stroke-like symptoms totally and rapidly disappeared. The efficiency of l-arginine in stroke-like episodes was initially reported then confirmed in a controlled study. The pathophysiology of stoke-like episodes and the mechanisms underlying the action of l-arginine are discussed.

MELAS and Kearns–Sayre overlap syndrome due to the mtDNA m. A3243G mutation and large-scale mtDNA deletions

Directory of Open Access Journals (Sweden)

Nian Yu

2016-09-01

Full Text Available This paper reported an unusual manifestation of a 19-year-old Chinese male patient presented with a complex phenotype of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS syndrome and Kearns–Sayre syndrome (KSS. He was admitted to our hospital with the chief complaint of “acute fever, headache and slow reaction for 21 days”. He was initially misdiagnosed as “viral encephalitis”. This Chinese man with significant past medical history of intolerating fatigue presented paroxysmal neurobehavioral attacks that started about 10 years ago. During this span, 3 or 4 attack clusters were described during which several attacks occurred over a few days. The further examination found that the hallmark signs of this patient included progressive myoclonus epilepsy, cerebellar ataxia, hearing loss, myopathic weakness, ophthalmoparesis, pigmentary retinopathy and bifascicular heart block (Wolff–Parkinson–White syndrome. By young age the disease progression is characterized by the addition of migraine, vomiting, and stroke-like episodes, symptoms of MELAS expression, which indicated completion of the MELAS/KSS overlap syndrome. The m. A3243G mitochondrial DNA mutation and single large-scale mtDNA deletions were found in this patient. This mutation has been reported with MELAS, KSS, myopathy, deafness and mental disorder with cognitive impairment. This is the first description with a MELAS/KSS syndrome in Chinese.

Tc-99m ECD brain SPECT in MELAS syndrome: comparison with MR finding

International Nuclear Information System (INIS)

Park, Sang Joon; Ryu, Young Hoon; Yoon, Pyeong Ho; Jeon, Tae Joo; Kim, Jai Keun; Nam, Ji Eun; Lee, Jong Doo; Lee, Byung Hee; Shin, Hyung Cheol

1998-01-01

The purpose of this study was to evaluate SPECT findings of MELAS syndrome and mitochondrial myopathy and correlate them with MR findings in search of specific imaging features and to assess the role of SPECT in MELAS syndrome. Five patients (four females and one male; age range, 1 to 25 years) who presented with repeated stroke-like episodes or seizures or developmental delay or were asymptomatic but had elevated lactic acid in CSF and serum were evaluated with conventional noncontrast MR imaging and SPECT. MRI demonstrated increased T2 signal intensities in the affected areas of gray and white matters mainly on the parietal (4/5) and occipital lobes (4/5) and in the basal ganglias (1/5), which were not restricted to a specific vascular territory. SPECT demonstrated decreased uptake of Tc-99m ECD on parietal (5/5) and occipital (4/5) and temporal (2/5) and frontal (1/5) lobe and basal ganglia (2/5) and thalami (2/5). In a patient with mitochondrial myopathy who had normal MRI, decreased perfusion is noted on left parietal area and bilateral thalami. Comparison of the numbers of abnormal findings revealed that decreased perfusion seen on SPECT were more numerous than anatomical abnormalities seen on MRI. SPECT may be a sensitive method for pathophysiological study of metabolic disturbances in MELAS. Moreover, in patients with mitochondrial myopathy without clinical encephalopathy, SPECT may play a role in evaluating subclinical encephalopathy even with normal conventional MR findings

Application of molecular imaging combined with genetic screening in diagnosing MELAS, diabetes and recurrent pancreatitis.

Science.gov (United States)

Zhiping, W; Quwen, L; Hai, Z; Jian, Z; Peiyi, G

2016-01-01

We report molecular imaging combined with gene diagnosis in a family with 7 members who carried an A3243G mutation in mitochondrial tRNA and p.Thr 137 Met in cationic trypsinogen (PRSS1) gene presented with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), diabetes, and recurrent pancreatitis. DNA sequencing was used to detect and validate mitochondrial DNA and PRSS1. We also verified that mitochondrial heterozygous mutations and c.410 C>T mutation causing p.Thr 137 Met could be detected in oral epithelial cells or in urine sediment cells. In addition, molecular imaging was carried out in the affected family members. In this pedigree, MELAS syndrome accompanied by pancreatitis was an important clinical feature, followed by diabetes. Heteroplasmy of the mtDNA A3243G and c.410 C>T mutation of PRSS1 was found in all tissue samples of these patients, but no mutations were found in 520 normal control and normal individuals of the family. However, based on molecular imaging observations, patients with relatively higher lactate/pyruvate levels had more typical and more severe symptoms, particularly those of pancreatic disease (diabetes or pancreatitis). MELAS syndrome may be associated with pancreatitis. For the diagnosis, it is more reasonable to perform molecular imaging combined with gene diagnosis.

Clinical analysis of three children patients with MELAS

Directory of Open Access Journals (Sweden)

Xiao-jun LIU

2016-05-01

Full Text Available This study aims to investigate the clinical manifestations, laboratory and imaging features, pathological and genetic testing, diagnosis and treatment in 3 children patients with mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS. Focal refractory epileptic seizures were the main clinical manifestations of 3 children, at the same time with stroke-like episodes, exercise intolerance, short stature, paroxysmal headache, vomiting, cognitive impairment, visual impairment, increased blood lactic acid (LA level and metabolic acidosis. Head MRI showed the lesions were located in temporo-parieto-occipital lobes, and EEG showed slow-wave background, bilateral asymmetry and interictal epileptiform discharges of occiput. Mitochondrial DNA (mtDNA A3243G mutation was found in the peripheral blood samples of 2 cases. The mutation was not detected in the other case, however, the muscle biopsy revealed pathological changes of mitochondrial myopathy. All 3 cases were treated by antiepileptic drugs (AEDs including topiramate, levetiracetam and oxcarbazepine, and cocktail therapy. One case died of status epilepticus (SE after 46 months of follow-up, one case had stroke-like episodes for 2-3 times per year during the follow-up of 40 months, and one case was lost. The clinical manifestations, laboratory and imaging characteristics, pathological and genetic testing in children of MELAS have certain features, which will be helpful for early identification and definite diagnosis, and thus may reduce misdiagnosis and mistreatment. DOI: 10.3969/j.issn.1672-6731.2016.05.009

N-isopropyl-p-[123I]iodoamphetamine SPECT in MELAS syndrome: Comparison with CT and MR imaging

International Nuclear Information System (INIS)

Satoh, M.; Ishikawa, N.; Yoshizawa, T.; Takeda, T.; Akisada, M.

1991-01-01

Regional cerebral perfusion was studied in three patients with the mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome, using single photon emission computed tomography (SPECT) with N-isopropyl-p-[123I]iodoamphetamine (IMP). Accumulation of the tracer was relatively decreased in the parietooccipital regions and also in the frontotemporal regions after stroke-like episodes. However, quantitative regional cerebral blood flow (rCBF) measurement showed that rCBF was relatively well preserved even at these sites, and a hyperemic state was observed at the sites of normal accumulation. IMP SPECT may be useful in the diagnosis and assessment of the progress of the MELAS syndrome

Target Transformation Constrained Sparse Unmixing (ttcsu) Algorithm for Retrieving Hydrous Minerals on Mars: Application to Southwest Melas Chasma

Science.gov (United States)

Lin, H.; Zhang, X.; Wu, X.; Tarnas, J. D.; Mustard, J. F.

2018-04-01

Quantitative analysis of hydrated minerals from hyperspectral remote sensing data is fundamental for understanding Martian geologic process. Because of the difficulties for selecting endmembers from hyperspectral images, a sparse unmixing algorithm has been proposed to be applied to CRISM data on Mars. However, it's challenge when the endmember library increases dramatically. Here, we proposed a new methodology termed Target Transformation Constrained Sparse Unmixing (TTCSU) to accurately detect hydrous minerals on Mars. A new version of target transformation technique proposed in our recent work was used to obtain the potential detections from CRISM data. Sparse unmixing constrained with these detections as prior information was applied to CRISM single-scattering albedo images, which were calculated using a Hapke radiative transfer model. This methodology increases success rate of the automatic endmember selection of sparse unmixing and could get more accurate abundances. CRISM images with well analyzed in Southwest Melas Chasma was used to validate our methodology in this study. The sulfates jarosite was detected from Southwest Melas Chasma, the distribution is consistent with previous work and the abundance is comparable. More validations will be done in our future work.

Defective mitochondrial rRNA methyltransferase MRM2 causes MELAS-like clinical syndrome.

Science.gov (United States)

Garone, Caterina; D'Souza, Aaron R; Dallabona, Cristina; Lodi, Tiziana; Rebelo-Guiomar, Pedro; Rorbach, Joanna; Donati, Maria Alice; Procopio, Elena; Montomoli, Martino; Guerrini, Renzo; Zeviani, Massimo; Calvo, Sarah E; Mootha, Vamsi K; DiMauro, Salvatore; Ferrero, Ileana; Minczuk, Michal

2017-11-01

Defects in nuclear-encoded proteins of the mitochondrial translation machinery cause early-onset and tissue-specific deficiency of one or more OXPHOS complexes. Here, we report a 7-year-old Italian boy with childhood-onset rapidly progressive encephalomyopathy and stroke-like episodes. Multiple OXPHOS defects and decreased mtDNA copy number (40%) were detected in muscle homogenate. Clinical features combined with low level of plasma citrulline were highly suggestive of mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome, however, the common m.3243 A > G mutation was excluded. Targeted exome sequencing of genes encoding the mitochondrial proteome identified a damaging mutation, c.567 G > A, affecting a highly conserved amino acid residue (p.Gly189Arg) of the MRM2 protein. MRM2 has never before been linked to a human disease and encodes an enzyme responsible for 2'-O-methyl modification at position U1369 in the human mitochondrial 16S rRNA. We generated a knockout yeast model for the orthologous gene that showed a defect in respiration and the reduction of the 2'-O-methyl modification at the equivalent position (U2791) in the yeast mitochondrial 21S rRNA. Complementation with the mrm2 allele carrying the equivalent yeast mutation failed to rescue the respiratory phenotype, which was instead completely rescued by expressing the wild-type allele. Our findings establish that defective MRM2 causes a MELAS-like phenotype, and suggests the genetic screening of the MRM2 gene in patients with a m.3243 A > G negative MELAS-like presentation. © The Author 2017. Published by Oxford University Press.

MELAS Syndrome with Cardiac Involvement: A Multimodality Imaging Approach

Directory of Open Access Journals (Sweden)

Sara Seitun

2016-01-01

Full Text Available A 49-year-old man presented with chest pain, dyspnea, and lactic acidosis. Left ventricular hypertrophy and myocardial fibrosis were detected. The sequencing of mitochondrial genome (mtDNA revealed the presence of A to G mtDNA point mutation at position 3243 (m.3243A>G in tRNALeu(UUR gene. Diagnosis of cardiac involvement in a patient with Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes syndrome (MELAS was made. Due to increased risk of sudden cardiac death, cardioverter defibrillator was implanted.

Increased accumulation of N-isopropyl-p-(123I)-iodoamphetamine in two cases with mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes (MELAS)

International Nuclear Information System (INIS)

Morita, K.; Ono, S.; Fukunaga, M.; Morita, R.; Yasuda, T.; Higashi, Y.; Terao, A.

1989-01-01

We present two cases with mitochondrial encephalopathy with lactic acidosis and strokelike episodes (MELAS), which showed both increased and decreased accumulation of N-isopropyl-p-( 123 I)-iodoamphetamine ( 123 I-IMP) in single photon emission computed tomography (SPECT). The increased accumulation of the tracer occurred before low density appeared on conventional computed tomography, suggesting that 123 I-IMP SPECT may be useful in pathophysiological study of MELAS. (orig.)

MELAS syndrome associated with both A3243G-tRNALeu mutation and multiple mitochondrial DNA deletions.

Science.gov (United States)

Aharoni, Sharon; Traves, Teres A; Melamed, Eldad; Cohen, Sarit; Silver, Esther Leshinsky

2010-09-15

The syndrome of mitochondrial encephalopathy, lactic acidosis, and stroke-like episode (MELAS) is characterized clinically by recurrent focal neurological deficits, epilepsy, and short stature. The phenotypic spectrum is extremely diverse, with multisystemic organ involvement leading to isolated diabetes, deafness, renal tubulopathy, hypertrophic cardiomyopathy, and retinitis pigmentosa. In 80% of cases, the syndrome is associated with an AG transmission mutation (A3243G) in the tRNALeu gene of the mitochondrial DNA (mtDNA). We describe a woman with a unique combination of the MELAS A3243G mutation and multiple mtDNA deletions with normal POLG sequence. The patient presented with diabetes mellitus, sensorineural deafness, short stature, and mental disorientation. All her three children died in early adolescence. 2010 Elsevier B.V. All rights reserved.

Ocular findings in MELAS syndrome – a case report.

Science.gov (United States)

Modrzejewska, Monika; Chrzanowska, Martyna; Modrzejewska, Anna; Romanowska, Hanna; Ostrowska, Iwona; Giżewska, Maria

We present a case of a child with MELAS syndrome (mitochondrial encephalo-myopathy with lactic acidosis and stroke-like episodes), discussing clinical manifestation, ocular findings and diagnostic challenges. Predominant ocular symptom was a transient complete visual loss, while the predominant ocular sign was a visual field defect. The diagnosia was based on clinical manifestation, laboratory tests, brain scans and genetic testing which confirmed the pathognomonic mutation in the MTTL1 gene encoding the mitochondrial tRNA for leucine 3243> G. Ocular examination demonstrated decreased visual acuity (with bilateral best corrected visual acuity of .1). Periodical, transient visual loss and visual field defects were clinically predominant. Specialist investigations were carried out, which demonstrated homonymous hemianopia (kinetic perimetry), bilateral partial optic nerve atrophy (RetCam). Funduscopy and electrophysiology mfERG study did not confirm features of retinitis pigmentosa. The brain scans revealed numerous small cortical ischemic lesions within the frontal, parietal and temporal lobes, post-stroke focal areas within the occipital lobes and diffuse calcifications of the basal ganglia. During several years of follow-up, visual field defects showed progressive concentric narrowing. The patient received a long-term treatment with arginine, coenzyme Q and vitamin D, both oral and intravenous, but no beneficial effect for the improvement of ophthalmic condition was observed. As it is the case in severe MELAS syndrome, the course of disease was fatal and the patientdied at the age of 14.

Brachiola gambiae sp n. the microsporidian parasite of Anopheles gambiae and A-melas in Liberia

Czech Academy of Sciences Publication Activity Database

Weiser, Jaroslav; Žižka, Zdeněk

2004-01-01

Roč. 43, č. 1 (2004), s. 73-80 ISSN 0065-1583 Institutional research plan: CEZ:AV0Z5007907 Keywords : Anopheles gambiae * Anopheles melas * Brachiola gambiae Subject RIV: EG - Zoology Impact factor: 0.986, year: 2004

Levels of Heavy Metals in Adolescents Living in the Industrialised Area of Milazzo-Valle del Mela (Northern Sicily

Directory of Open Access Journals (Sweden)

Monica Interdonato

2014-01-01

Full Text Available In the Milazzo-Valle del Mela area, the presence of industrial plants and the oil refinery make local residents concerned for their health. For this reason, we evaluated the levels of heavy metals in 226 children aged 12–14 years, living in the 7 municipalities of the area. A control age-matched population (n=29 living 45 km far from the industrial site was also enrolled. Arsenic, cadmium, chromium, mercury, nickel, and vanadium were analysed in 24 h urine samples, while lead concentration was evaluated in blood samples. A questionnaire regarding life style and risk perception was also administered. Adolescents from Milazzo-Valle del Mela had cadmium levels significantly higher compared to either controls  (P<0.0001 or the reference values of the European Germany Environmental Survey (GerES-IV and the American National Health and Nutrition Examination Survey (NHANES. Furthermore, children had higher perception of living in a high-risk environment. The present data, for the first time, clearly indicate that adolescents living in Milazzo-Valle del Mela have increased body concentration of cadmium, which may be harmful to human health. These results deserve particular attention by the local and regional government to initiate prevention programmes in this susceptible population.

Video e comunicazione scientifica. Il laboratorio MELA dell’Università di Bologna

Directory of Open Access Journals (Sweden)

Laura Corazza

2010-07-01

Full Text Available Al Media Education e-learning LAboratorio del Dipartimento di Scienze dell’educazione e della Facoltà di Scienze della formazione, Università di Bologna, un gruppo di esperti e di tecnici svolge attività di supporto alla didattica e alla ricerca, lavorando con i docenti per produrre audiovisivi e materiali multimediali. I prodotti MELA sono video per l’approfondimento culturale, per la produzione scientifica, per la documentazione.

Chronic kidney disease, severe arterial and arteriolar sclerosis and kidney neoplasia: on the spectrum of kidney involvement in MELAS syndrome.

Science.gov (United States)

Piccoli, Giorgina Barbara; Bonino, Laura Davico; Campisi, Paola; Vigotti, Federica Neve; Ferraresi, Martina; Fassio, Federica; Brocheriou, Isabelle; Porpiglia, Francesco; Restagno, Gabriella

2012-02-21

MELAS syndrome (MIM ID#540000), an acronym for Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-like episodes, is a genetically heterogeneous mitochondrial disorder with protean manifestations and occasional kidney involvement. Interest in the latter is rising due to the identification of cases with predominant kidney involvement and to the hypothesis of a link between mitochondrial DNA and kidney neoplasia. We report the case of a 41-year-old male with full blown MELAS syndrome, with lactic acidosis and neurological impairment, affected by the "classic" 3243A > G mutation of mitochondrial DNA, with kidney cancer. After unilateral nephrectomy, he rapidly developed severe kidney functional impairment, with nephrotic proteinuria. Analysis of the kidney tissue at a distance from the two tumor lesions, sampled at the time of nephrectomy was performed in the context of normal blood pressure, recent onset of diabetes and before the appearance of proteinuria. The morphological examination revealed a widespread interstitial fibrosis with dense inflammatory infiltrate and tubular atrophy, mostly with thyroidization pattern. Vascular lesions were prominent: large vessels displayed marked intimal fibrosis and arterioles had hyaline deposits typical of hyaline arteriolosclerosis. These severe vascular lesions explained the different glomerular alterations including ischemic and obsolescent glomeruli, as is commonly observed in the so-called "benign" arteriolonephrosclerosis. Some rare glomeruli showed focal segmental glomerulosclerosis; as the patient subsequently developed nephrotic syndrome, these lesions suggest that silent ischemic changes may result in the development of focal segmental glomerulosclerosis secondary to nephron loss. Nephron loss may trigger glomerular sclerosis, at least in some cases of MELAS-related nephropathy. Thus the incidence of kidney disease in the "survivors" of MELAS syndrome may increase as the support therapy of these patients improves.

[Identification of an ideal noninvasive method to detect A3243G gene mutation in MELAS syndrome].

Science.gov (United States)

Ma, Yi-nan; Fang, Fang; Yang, Yan-ling; Zhang, Ying; Wang, Song-tao; Xu, Yu-feng; Pei, Pei; Yuan, Yun; Bu, Ding-fang; Qi, Yu

2008-12-16

To identify a better non-invasive method to detect the carrier of mitochondrial A3243G mutation, a cause of mitochondrial encephalopathy-lactic acidosis-stroke like episode (MELAS) syndrome. DNA was extracted from the peripheral blood, urine, hair follicle, and saliva of 25 MELAS syndrome patients carrying A3243G mutation and their mothers and other maternal relatives, 33 persons in number, and the muscle tissues from 5 patients obtained by biopsy. A3243G mutation was detected by PCR-RFLP method, and the A3243G mutation ratio was identified by measuring the density of each band and calculation with the software AlphaEase 5.0. A3243G mutations were detected in all tissues of the 25 MELAS patients. The A3243G mutation ratio in urine was 62% +/- 9%, significantly higher than that in the blood [(36% +/- 10%), t = -11.13, P < 0.01]. A3243G mutations were detected in at least one tissue of the 28 maternal relatives. The A3243G mutation rates in their urine samples was 33.0% (5.0% - 70.4%), significantly higher than that in their blood samples [8.0% (0 - 33.3%), z = -4.197, P < 0.01]. There was no significant difference in A3243G mutation ratio among the samples of hair follicle, saliva, and blood. The A3243G mutation ratio in urine is significantly higher than those in blood samples of the patients and their maternal relatives. A noninvasive method, A3243G mutation ratio analysis of urine is superior to that in blood.

The accumulation of assembly intermediates of the mitochondrial complex I matrix arm is reduced by limiting glucose uptake in a neuronal-like model of MELAS syndrome.

Science.gov (United States)

Geffroy, Guillaume; Benyahia, Rayane; Frey, Samuel; Desquiret-Dumas, Valerie; Gueguen, Naig; Bris, Celine; Belal, Sophie; Inisan, Aurore; Renaud, Aurelie; Chevrollier, Arnaud; Henrion, Daniel; Bonneau, Dominique; Letournel, Franck; Lenaers, Guy; Reynier, Pascal; Procaccio, Vincent

2018-05-01

Ketogenic diet (KD) which combined carbohydrate restriction and the addition of ketone bodies has emerged as an alternative metabolic intervention used as an anticonvulsant therapy or to treat different types of neurological or mitochondrial disorders including MELAS syndrome. MELAS syndrome is a severe mitochondrial disease mainly due to the m.3243A > G mitochondrial DNA mutation. The broad success of KD is due to multiple beneficial mechanisms with distinct effects of very low carbohydrates and ketones. To evaluate the metabolic part of carbohydrate restriction, transmitochondrial neuronal-like cybrid cells carrying the m.3243A > G mutation, shown to be associated with a severe complex I deficiency was exposed during 3 weeks to glucose restriction. Mitochondrial enzyme defects were combined with an accumulation of complex I (CI) matrix intermediates in the untreated mutant cells, leading to a drastic reduction in CI driven respiration. The severe reduction of CI was also paralleled in post-mortem brain tissue of a MELAS patient carrying high mutant load. Importantly, lowering significantly glucose concentration in cell culture improved CI assembly with a significant reduction of matrix assembly intermediates and respiration capacities were restored in a sequential manner. In addition, OXPHOS protein expression and mitochondrial DNA copy number were significantly increased in mutant cells exposed to glucose restriction. The accumulation of CI matrix intermediates appeared as a hallmark of MELAS pathophysiology highlighting a critical pathophysiological mechanism involving CI disassembly, which can be alleviated by lowering glucose fuelling and the induction of mitochondrial biogenesis, emphasizing the usefulness of metabolic interventions in MELAS syndrome. Copyright © 2018 Elsevier B.V. All rights reserved.

99mTc-ECD and 99mTc-HM-PAO SPECT in five patients with MELAS

International Nuclear Information System (INIS)

Katagiri, Shinako; Nishimaki, Hiroshi; Kitano, Masashi; Horiike, Shigeharu; Kan, Shinichi; Ishii, Katsumi; Matsubayashi, Takashi; Sakai, Fumihiko

1998-01-01

Cerebral perfusion was studied in five patients with mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes syndrome (MELAS), using single photon emission computed tomography (SPECT) with 99m Tc-ethyl cysteinate dimer ( 99m Tc-ECD) or 99m Tc-hexamethyl propyleneamine oxime ( 99m Tc-HM-PAO). In four cases, regional cerebral blood flow (rCBF) was evaluated by the method reported by Mastuda et al. Immediately after the stroke-like episodes, accumulation of the tracer was relatively increased in the temporooccipital lobe, and also increased rCBF was shown in the same area. However, the region showed decreased radioactivity at the chronic stage, and rCBF decreased also. These findings are consistent with positron emission tomography (PET) at the acute stage and autopsy. 99m Tc-ECD SPECT and 99m Tc-HM-PAO SPECT may be useful in the diagnosis and assessment of the progress of the MELAS. (author)

Epidemiologia da mela e produtividade do feijoeiro-comum tratado com fungicidas

Directory of Open Access Journals (Sweden)

Gesimária Ribeiro Costa-Coelho

2012-09-01

Full Text Available O efeito dos fungicidas azoxistrobina, carbendazim, mancozebe, tebuconazole, hidróxido de fenilestanho, piraclostrobina, trifloxistrobina + ciproconazol, trifloxistrobina + propiconazol e clorotalonil no progresso da mela e na produtividade do feijoeiro foi avaliado em campo e casa de vegetação. No campo, três experimentos foram conduzidos nas estações chuvosas de 2004/05, 2005/06 e 2006/07, em blocos ao acaso com quatro repetições.Na safra 2004/05 foi realizada apenas uma aplicação, aos 45 dias após o plantio (DAP; em 2005/06 foram realizadas duas aplicações aos 30 e 45 DAP e em 2006/07 foram realizadas três aplicações, aos 30, 45 e 60 DAP. A avaliação da severidade da doença foi feita semanalmente, atribuindo-se notas de 1 (sem sintomas a 9 (acima de 90% da área foliar destruída e taxas de progresso da doença foram calculadas após o ajuste das curvas de progresso ao modelo logístico. Os resultados mostraram que uma única aplicação de qualquer dos produtos, aos 45 DAP, foi ineficiente para o controle da taxa de progresso da mela (taxa média, r = 0,2348. A eficiência do controle aumentou com o incremento do número de aplicações e aplicações mais precoces, iniciando-se aos 30 DAP (médias de r = 0,1988 e 0,1671 em 2005/06 e 2006/07, respectivamente. Com três aplicações,as menores severidades de doença foram observadas com hydróxido de fenil estanho, trifloxistrobina + propiconazol e trifloxistrobina + cyproconazol. Em casa de vegetação, o efeito protetor e curativo dos fungicidas foi estudado com aplicação dos produtos em pré ou pós-inoculação de folíolos, através da avaliação do diâmetro das lesões. Todos os fungicidas apresentaram tanto efeito protetor quanto curativo, mas os melhores resultados foram observados em aplicação preventiva.Foi encontrada alta correlação negativa entre intensidade da mela e a produção do feijoeiro e o ganho em produtividade com uso de fungicidas chegou a 304 %.

A preliminary report on settlement layout and gold melting at Thula Mela, a Late Iron Age site in the Kruger National Park

Directory of Open Access Journals (Sweden)

M.M. Kusel

1992-09-01

Full Text Available Archaeological investigations at a Late Iron Age stone-walled hill site, Thula Mela, near the Luvuvhu River in the Pafuri area of the Kruger National Park, have produced evidence of gold melting. The recovery of two fragments of pottery crucibles with the remains of slag and gold globules and three gold beads from a test trench in a midden at Thula Mela represents the first direct evidence of indigenous gold melting in South Africa. From radiocarbon dates it was established that this site was occupied between the fifteenth and early seventeenth century AD.

Crystallisation of mela-aillikites of the Narsaq region, Gardar alkaline province, south Greenland and relationships to other aillikitic carbonatitic associations in the province

Science.gov (United States)

Upton, B. G. J.; Craven, J. A.; Kirstein, L. A.

2006-11-01

Aillikites (carbonated, melilite-free ultramafic lamprophyres grading to carbonatites) are minor components of the Gardar alkaline igneous province. They occur principally as minor intrusions and as clasts in diatremes, but more voluminous aillikitic intrusions crop out near the Ilímaussaq Complex, which they predate by a few million years. These larger intrusions were emplaced at 1160 ± 5 Ma. They are essentially carbonate-free and, consisting almost wholly of ferromagnesian silicate and oxide minerals, are mela-aillikites. Typically the mela-aillikites are fine-grained rocks composed largely of olivine, clinopyroxene, phlogopite and magnetite that crystallised in open systems, permitting loss of volatile-rich residues. The petrography is highly complex, involving at least 28 mineral species. Pyroxenitic veins were emplaced while the host-rocks were still at high temperatures and represent channels through which fluorinated silico-carbonatitic residual melts escaped, with exsolving CO 2 as propellant. Precipitation of Ca-rich minerals including monticellite, perovskite, vesuvianite, wollastonite and cuspidine was a result of dissociation of the calcium carbonate in the residual melts. Late-stage crystallisation was in a highly oxidising environment in which the 'common minerals' attain extreme compositions (almost pure forsterite, ferrian-diopside, highly magnesian ilmenite, Ba-Ti-rich phlogopite and Sr-rich kaersutite). Spatially associated diatremes may be vents through which CO 2-rich gases erupted. The whole-rock compositions are considered to be well removed from those of co-existing melts: compaction and expulsion of highly mobile residual melts is inferred to have left the mela-aillikites as aberrant cumulates. The mela-aillikites are a late-Gardar manifestation of the aillikitic magmatism that occurred intermittently in the province for over 120 Ma. Repetitive formation of metasomite vein systems in the deep lithospheric mantle is postulated. These

A yeast glycolipid biosurfactant, mannosylerythritol lipid, shows potential moisturizing activity toward cultured human skin cells: the recovery effect of MEL-A on the SDS-damaged human skin cells.

Science.gov (United States)

Morita, Tomotake; Kitagawa, Masaru; Suzuki, Michiko; Yamamoto, Shuhei; Sogabe, Atsushi; Yanagidani, Shusaku; Imura, Tomohiro; Fukuoka, Tokuma; Kitamoto, Dai

2009-01-01

Mannosylerythritol lipids (MELs) are produced in large amounts from renewable vegetable oils by Pseudozyma antarctica, and are the most promising biosurfactants known due to its versatile interfacial and biochemical actions. In order to broaden the application in cosmetics and pharmaceuticals, the skin care property of MEL-A, the major component of MELs, was investigated using a three-dimensional cultured human skin model. The skin cells were cultured and treated with sodium dodecyl sulfate (SDS) solution of 1 wt%, and the effects of different lipids on the SDS-damaged cells were then evaluated on the basis of the cell viability. The viability of the damaged cells was markedly recovered by the addition of MEL-A in a dose-dependent manner. Compared to the control, MEL-A solutions of 5 wt% and 10 wt% gave the recovery rate of 73% and 91%, respectively, while ceramide solution of 1 wt% gave the rate of over 100%. This revealed that MEL-A shows a ceramide-like moisturizing activity toward the skin cells. Considering the drawbacks of natural ceramides, namely limited amount and high production cost, the yeast biosurfactants should have a great potential as a novel moisturizer for treating the damaged skin.

Progresso e controle da mela-das-sementes (Claviceps maximensis de Brachiaria brizantha Progress and control of honeydew (Claviceps maximensis of Brachiaria brizantha

Directory of Open Access Journals (Sweden)

Carlos Eduardo Marchi

2008-09-01

Full Text Available Verificou-se a eficiência de uma ou duas aplicações de Piraclostrobin + Epoxiconazole, Mancozeb, Triadimenol, Azoxistrobin + Ciproconazole, Trifloxistrobin + Ciproconazole ou Tebuconazole no controle da mela-das-sementes de Brachiaria brizantha cvs. Marandu e Xaraés, durante a safra 2004-05. Também foram avaliados os indutores de resistência Acibenzolar-S-Metil e Silicato de Potássio (via aérea ou solo. Triadimenol, com uma ou duas aplicações, Piraclostrobin + Epoxiconazole, Azoxistrobin + Ciproconazole, Trifloxistrobin + Ciproconazole ou Tebuconazole, com duas aplicações, foram promissores no controle da mela-das-sementes do capim-marandu. Já para a cv. Xaraés, melhor controle foi alcançado com o Piraclostrobin + Epoxiconazole, independente do número de aplicações, Triadimenol, Trifloxistrobin + Ciproconazole ou Tebuconazole, com duas aplicações. Não houve correlação entre os dados de produção de sementes puras e a intensidade da mela. Com relação ao progresso da mela-das-sementes de B. brizantha cvs. Marandu e Xaraés, constatou-se que a doença manifestou-se em períodos frios associados à umidade relativa alta. Na cv. Marandu a doença ocorreu na fase final da cultura, enquanto que na cv. Xaraés, a mela foi detectada na fase de intenso florescimento. Foram constatados aumentos na intensidade da doença em ambas as cultivares. A mela-das-sementes ocorreu em 64% das panículas da cv. Marandu e em 81% das panículas da cv. Xaraés; cerca de 20% e 18% das flores/sementes, respectivamente, foram afetadas. Os resultados demonstraram existir correlação positiva entre os valores de incidência e severidade da mela.The efficiency of one or two applications of Pyraclostrobin + Epoxyconazole, Mancozeb, Triadimenol, Azoxystrobin + Cyproconazole, Trifloxystrobin + Cyproconazole or Tebuconazole in the control of honeydew in seeds of Brachiaria brizantha cvs. Marandu and Xaraes was verified during crop 2004-05. The inductors

Behaviour of Short-finned Pilot Whales Globicephala macrorhynchus (Gray, 1846 (Mammalia: Cetartiodactyla: Delphinidae in the southeastern Arabian Sea

Directory of Open Access Journals (Sweden)

Kurichithara K. Sajikumar

2014-10-01

Full Text Available We report the presence and behaviour of a pod of short-finned pilot whale Globicephala macrorhynchus in the southeastern Arabian Sea. The pod was observed in the southeastern side of Minicoy Island, in the Nine degree channel (09°219′23′′N;74°39′529′′E on 03.02.2013. Later, on 06.02.2013,the same pod of pilot whales were observed near Kalpeni Island (10°02′402′′N; 73°39′579′′E 130 km northwest of the previous location. The average length of the whales was estimated as 550 cm and weight as approximately 1200 kg. They were travelling in a northwesterly direction. The pod size of the whales sighted was twelve and several species specific behaviour such as side rolling, spyhopping, lobtailing, peduncle arching and movement patterns such as synchronous travelling and logging could be observed. The occurrence of scars and injuries on the body of four whales in the pod are also reported.

Mitochondrial Sensorineural Hearing Loss: A Retrospective Study and a Description of Cochlear Implantation in a MELAS Patient

Directory of Open Access Journals (Sweden)

Mauro Scarpelli

2012-01-01

Full Text Available Hearing impairment is common in patients with mitochondrial disorders, affecting over half of all cases at some time in the course of the disease. In some patients, deafness is only part of a multisystem disorder. By contrast, there are also a number of “pure” mitochondrial deafness disorders, the most common probably being maternally inherited. We retrospectively analyzed the last 60 genetically confirmed mitochondrial disorders diagnosed in our Department: 28 had bilateral sensorineural hearing loss, whereas 32 didn't present ear's abnormalities, without difference about sex and age of onset between each single group of diseases. We reported also a case of MELAS patient with sensorineural hearing loss, in which cochlear implantation greatly contributed to the patient's quality of life. Our study suggests that sensorineural hearing loss is an important feature in mitochondrial disorders and indicated that cochlear implantation can be recommended for patients with MELAS syndrome and others mitochondrial disorders.

Epilepsy Characteristics and Clinical Outcome in Patients With Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-Like Episodes (MELAS).

Science.gov (United States)

Lee, Ha Neul; Eom, Soyong; Kim, Se Hoon; Kang, Hoon-Chul; Lee, Joon Soo; Kim, Heung Dong; Lee, Young-Mock

2016-11-01

Epileptic seizures in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) are heterogeneous with no pathognomonic features. We reviewed epilepsy characteristics and clinical outcome exclusively in a pediatric population. Twenty-two children and adolescents (13 males) with confirmed mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes due to mitochondrial DNA A3243G mutation and epilepsy were recruited. Clinical data including seizure semiology, treatment response, neuroimaging findings, and electroencephalography were analyzed. We also examined the effect of the age at seizure onset and initial symptoms on the clinical variables. Seizure semiology and electroencephalography abnormalities showed no syndrome-specific findings. Focal seizures occurred in 21 of 22 subjects (95.5%), whereas generalized seizures developed in seven of 22 subjects (31.8%). Twenty of 22 subjects (90.9%) achieved partial to complete reduction of clinical seizures for more than one year with a combination of more than two antiepileptic drugs. The subgroup with earlier seizure onset presented significantly earlier and showed significantly higher rates of drug-resistant epilepsy compared with the late onset group, although there were no significant differences in the initial symptoms. The subjects with severe epileptic conditions tended to have more severe clinical dysfunction and more severe organ involvement. Both focal and generalized seizures occurred in patients with MELAS. Epilepsy in this population is drug resistant, but a certain degree of clinical seizure reduction was achievable with antiepileptic drugs, with more favorable outcomes than historically expected. Close observation and active epilepsy treatment of individuals with MELAS episodes and earlier seizure onset might improve the prognosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Spectral and stratigraphic mapping of hydrated minerals associated with interior layered deposits near the southern wall of Melas Chasma, Mars

Science.gov (United States)

Liu, Yang; Goudge, Timothy A.; Catalano, Jeffrey G.; Wang, Alian

2018-03-01

Orbital remote sensing data acquired from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) onboard Mars Reconnaissance Orbiter (MRO), in conjunction with other datasets, are used to perform detailed spectral and stratigraphic analyses over a portion of south Melas Chasma, Mars. The Discrete Ordinate Radiative Transfer (DISORT) model is used to retrieve atmospherically corrected single scattering albedos from CRISM I/F data for mineral identification. A sequence of interbedded poly- and monohydrated sulfates associated with interior layered deposits (ILDs) is identified and mapped. Analyses from laboratory experiments and spectral unmixing of CRISM hyperspectral data support the hypothesis of precipitation and dehydration of multiple inputs of complex Mg-Ca-Fe-SO4-Cl brines. In this scenario, the early precipitated Mg sulfates could dehydrate into monohydrated sulfate due to catalytic effects, and the later-precipitated Mg sulfates from the late-stage "clean" brine could terminate their dehydration at mid-degree of hydration to form a polyhydrated sulfate layer due to depletion of the catalytic species (e.g., Ca, Fe, and Cl). Distinct jarosite-bearing units are identified stratigraphically above the hydrated sulfate deposits. These are hypothesized to have formed either by oxidation of a fluid containing Fe(II) and SO4, or by leaching of soluble phases from precursor intermixed jarosite-Mg sulfate units that may have formed during the later stages of deposition of the hydrated sulfate sequence. Results from stratigraphic analysis of the ILDs show that the layers have a consistent northward dip towards the interior of the Melas Chasma basin, a mean dip angle of ∼6°, and neighboring strata that are approximately parallel. These strata are interpreted as initially sub-horizontal layers of a subaqueous, sedimentary evaporite deposits that underwent post-depositional tilting from slumping into the Melas Chasma basin. The interbedded hydrated sulfate

MODELO DE PONTO CRÍTICO PARA ESTIMAR DANOS CAUSADOS PELA MELA NA CULTURA DO FEIJOEIRO

Directory of Open Access Journals (Sweden)

Felipe Rafael Garcés Fiallos

2011-07-01

Full Text Available No Equador, o feijão (Phaseolus vulgaris L. é consumido quase pela totalidade da população, sendo também fonte de renda para pequenos e médios produtores. Uma das doenças mais importantes é a mela, ou podridão radicular de rizoctonia, causada pelo fungo necrotrófico Rhizoctonia solani Khun (teleomorfo Thanatephorus cucumeris Frank. Objetivou-se determinar a redução no rendimento de grãos causados pela infecção natural da mela, em diferentes cultivares de feijão, na safra agrícola 2010, no município de Quevedo, Equador. O delineamento experimental foi em blocos casualizados, com sete tratamentos e quatro repetições. O gradiente da intensidade da doença foi gerado pela variabilidade genética entre cultivares de feijoeiro. A avaliação de severidade (% de área foliar necrosada da doença foi determinada no estádio fenológico R7 (desenvolvimento de legume. A colheita foi realizada em aos 124 dias pós-semeadura, para quantificação do rendimento. A equação da função de dano obtida foi R = 4,257.50 – 33.16 S, onde R é o rendimento de grãos e S a severidade (% da doença, com R2 = 0.82 e p<0.0001. A equação resultante foi normalizada para 1,000 kg, sendo esta R = 1,000.0 – 7.79 S. Concluiu-se que a equação gerada da função de dano pode ser utilizada no cálculo do limiar de dano econômico (LDE, uma alternativa racional indicadora do momento para a aplicação de controle químico da mela em cultivares suscetíveis, mantendo a rentabilidade do agricultor e ser amigável com o meio ambiente.

The ROS-sensitive microRNA-9/9* controls the expression of mitochondrial tRNA-modifying enzymes and is involved in the molecular mechanism of MELAS syndrome.

Science.gov (United States)

Meseguer, Salvador; Martínez-Zamora, Ana; García-Arumí, Elena; Andreu, Antonio L; Armengod, M-Eugenia

2015-01-01

Mitochondrial dysfunction activates mitochondria-to-nucleus signaling pathways whose components are mostly unknown. Identification of these components is important to understand the molecular mechanisms underlying mitochondrial diseases and to discover putative therapeutic targets. MELAS syndrome is a rare neurodegenerative disease caused by mutations in mitochondrial (mt) DNA affecting mt-tRNA(Leu(UUR)). Patient and cybrid cells exhibit elevated oxidative stress. Moreover, mutant mt-tRNAs(Leu(UUR)) lack the taurine-containing modification normally present at the wobble uridine (U34) of wild-type mt-tRNA(Leu(UUR)), which is considered an etiology of MELAS. However, the molecular mechanism is still unclear. We found that MELAS cybrids exhibit a significant decrease in the steady-state levels of several mt-tRNA-modification enzymes, which is not due to transcriptional regulation. We demonstrated that oxidative stress mediates an NFkB-dependent induction of microRNA-9/9*, which acts as a post-transcriptional negative regulator of the mt-tRNA-modification enzymes GTPBP3, MTO1 and TRMU. Down-regulation of these enzymes by microRNA-9/9* affects the U34 modification status of non-mutant tRNAs and contributes to the MELAS phenotype. Anti-microRNA-9 treatments of MELAS cybrids reverse the phenotype, whereas miR-9 transfection of wild-type cells mimics the effects of siRNA-mediated down-regulation of GTPBP3, MTO1 and TRMU. Our data represent the first evidence that an mt-DNA disease can directly affect microRNA expression. Moreover, we demonstrate that the modification status of mt-tRNAs is dynamic and that cells respond to stress by modulating the expression of mt-tRNA-modifying enzymes. microRNA-9/9* is a crucial player in mitochondria-to-nucleus signaling as it regulates expression of nuclear genes in response to changes in the functional state of mitochondria. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email

Improvement in symptoms of the syndrome of mitochondrial encephalopathy, lactic acidosis, and stroke-like symptoms (MELAS) following treatment with sympathomimetic amines--possible implications for improving fecundity in women of advanced reproductive age.

Science.gov (United States)

Potestio, C P; Check, J H; Mitchell-Williams, J

2014-01-01

To evaluate the efficacy of sympathomimetic amine therapy on a mitochondrial abnormality known as the mitochondrial encephalopathy lactic acidosis and stroke-like symptoms syndrome (MELAS syndrome). Dextroamphetamine sulfate 15 mg extended release capsule was prescribed to a woman with a 25 year history of MELAS syndrome refractory to most other therapies. Within one month of therapy the woman noticed considerable improvement in her chronic fatigue, pain, and edema. The MELAS syndrome is thus another condition to add to the list of various chronic refractory disorders that improve considerably after dextroamphetamine therapy. This is the first mitochondrial disorder shown to improve with sympathomimetic amines which could suggest that dextroamphetamine could prove useful in decreasing the risk of aneuploidy in women of advanced reproductive age.

Device for positioning and generation of an element of track model and slice of the MELAS automatic equipment

International Nuclear Information System (INIS)

Kryutchenko, E.V.; Fedotov, V.S.

1979-01-01

The structure and organization of the device for positioning and generation of element of track model and slice of the MELAS automatic equipment which is developed for measuring films from big bubble chambers, is described. Main features of the device are studied and characteristics are given as well

Disease-causing mitochondrial heteroplasmy segregated within induced pluripotent stem cell clones derived from a patient with MELAS.

Science.gov (United States)

Folmes, Clifford D L; Martinez-Fernandez, Almudena; Perales-Clemente, Ester; Li, Xing; McDonald, Amber; Oglesbee, Devin; Hrstka, Sybil C; Perez-Terzic, Carmen; Terzic, Andre; Nelson, Timothy J

2013-07-01

Mitochondrial diseases display pathological phenotypes according to the mixture of mutant versus wild-type mitochondrial DNA (mtDNA), known as heteroplasmy. We herein examined the impact of nuclear reprogramming and clonal isolation of induced pluripotent stem cells (iPSC) on mitochondrial heteroplasmy. Patient-derived dermal fibroblasts with a prototypical mitochondrial deficiency diagnosed as mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) demonstrated mitochondrial dysfunction with reduced oxidative reserve due to heteroplasmy at position G13513A in the ND5 subunit of complex I. Bioengineered iPSC clones acquired pluripotency with multilineage differentiation capacity and demonstrated reduction in mitochondrial density and oxygen consumption distinguishing them from the somatic source. Consistent with the cellular mosaicism of the original patient-derived fibroblasts, the MELAS-iPSC clones contained a similar range of mtDNA heteroplasmy of the disease-causing mutation with identical profiles in the remaining mtDNA. High-heteroplasmy iPSC clones were used to demonstrate that extended stem cell passaging was sufficient to purge mutant mtDNA, resulting in isogenic iPSC subclones with various degrees of disease-causing genotypes. On comparative differentiation of iPSC clones, improved cardiogenic yield was associated with iPSC clones containing lower heteroplasmy compared with isogenic clones with high heteroplasmy. Thus, mtDNA heteroplasmic segregation within patient-derived stem cell lines enables direct comparison of genotype/phenotype relationships in progenitor cells and lineage-restricted progeny, and indicates that cell fate decisions are regulated as a function of mtDNA mutation load. The novel nuclear reprogramming-based model system introduces a disease-in-a-dish tool to examine the impact of mutant genotypes for MELAS patients in bioengineered tissues and a cellular probe for molecular features of individual

Geologic context of recurring slope lineae in Melas and Coprates Chasmata, Mars

Science.gov (United States)

Chojnacki, Matthew; McEwen, Alfred; Dundas, Colin M.; Ojha, Lujendra; Urso, Anna; Sutton, Sarah

2016-01-01

One of the major Mars discoveries of recent years is the existence of recurring slope lineae (RSL), which suggests that liquid water occurs on or near the surface of Mars today. These dark and narrow features emerge from steep, rocky exposures and incrementally grow, fade, and reform on a seasonal basis and are detected in images from the High Resolution Imaging Science Experiment camera. RSL are known to occur at scattered midlatitude and equatorial sites with little spatial connection to one another. One major exception is the steep, low-albedo slopes of Melas and Coprates Chasmata, in Valles Marineris where RSL are detected among diverse geologic surfaces (e.g., bedrock and talus) and landforms (e.g., inselbergs and landslides). New images show topographic changes including sediment deposition on active RSL slopes. Midwall locations in Coprates and Melas appear to have more areally extensively abundant RSL and related fans as compared with other RSL sites found on Mars. Water budget estimates for regional RSL are on the order of 105 to 106 m3 of fluid, for depths of 10 to 100mm, and suggest that a significant amount of near-surface watermight be present. Many RSL are concentrated near local topographic highs, such as ridge crests or peaks, which is challenging to explain via groundwater or ice without a recharge mechanism. Collectively, results provide additional support for the notion that significant amounts of near-surface water can be found on Mars today and suggest that a widespread mechanism, possibly related to the atmosphere, is recharging RSL sources.

Fatty acid composition of cane molasses and yeasts Composição em ácidos graxos de melaço de cana-de-açúcar e de leveduras

Directory of Open Access Journals (Sweden)

L.E. Gutierrez

1993-12-01

Full Text Available Lipid extract and fatty acid composition of cane molasses and yeasts (Saccharomyces cerevisiae M-300-A and Saccharomyces uvarum IZ-1904 grown in molasses medium were determined. In molasses, linoleic acid was found in higher levels (around 42% and was followed by palmitic, oleic and linolenic acids. The lipid extract varied from 1.02 to 3.13 gkg-1. In yeasts, the level of lipid extract varied from 16.65 to 31.12 g.kg-1 (dry matter basis depending on the molasses type and yeast species. Both yeasts were able to incorporate fatty acids from molasses' and therefore linoleic and palmitic acids were the major fatty acids found in them.Foram determinados o extrato lipídico e a composição em ácidos graxos de melaço de cana-de-açúcar e das leveduras (Saccharomyces cerevisiae M-300-A e Saccharomyces uvarum Iz-1904 multiplicadas em meio fermentativo de melaço. Nos melaços, o ácido linoleico foi encontrado em maiores quantidades (cerca de 42% do total e foi seguido pelos ácidos palmitic o, oleico e linolênico. O extrato lipídico variou de 1,02 até 3,13 g.Kg-1. Em leveduras, o nível do extrato lipídico variou de 16,65 até 31,12 g.kg-1(com base na matéria seca e foi afetado pelo tipo de melaço e da espécie de levedura. Ambas as leveduras foram capazes de incorporar ácidos graxos presentes no melaço e portanto os ácidos linoleico e palmítico foram os principais ácidos graxos encontrados nessas leveduras.

Mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) may respond to adjunctive ketogenic diet.

Science.gov (United States)

Steriade, Claude; Andrade, Danielle M; Faghfoury, Hanna; Tarnopolsky, Mark A; Tai, Peter

2014-05-01

Mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome can present management challenges. Refractory seizures and stroke-like episodes leading to disability are common. We analyzed the clinical, electrophysiologic, and radiologic data of a 22-year-old woman with multiple episodes of generalized and focal status epilepticus and migratory cortical stroke-like lesions who underwent muscle biopsy for mitochondrial genome sequencing. Although initial mitochondrial genetic testing was negative, muscle biopsy demonstrated a mitochondrial DNA disease-causing mutation (m.3260A > G). New antiepileptic medications were added with each episode of focal status epilepticus with only temporary improvement, until a modified ketogenic diet and magnesium were introduced, leading to seizure freedom despite development of a new stroke-like lesion, and subsequent decrease in frequency of stroke-like episodes. We propose a metabolic model in which the ketogenic diet may lead to improvement of the function of respiratory chain complexes. The ketogenic diet may lead to improvement of mitochondrial dysfunction in MELAS, which in turn may promote better seizure control and less frequent stroke-like episodes. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Metabolically induced heteroplasmy shifting and L-arginine treatment reduce the energetic defect in a neuronal-like model of MELAS

Science.gov (United States)

Desquiret-Dumas, Valerie; Gueguen, Naig; Barth, Magalie; Chevrollier, Arnaud; Hancock, Saege; Wallace, Douglas C; Amati-Bonneau, Patrizia; Henrion, Daniel; Bonneau, Dominique; Reynier, Pascal; Procaccio, Vincent

2012-01-01

The m.3243A>G variant in the mitochondrial tRNALeu (UUR) gene is a common mitochondrial DNA (mtDNA) mutation. Phenotypic manifestations depend mainly on the heteroplasmy, i.e. the ratio of mutant to normal mtDNA copies. A high percentage of mutant mtDNA is associated with a severe, life-threatening neurological syndrome known as MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes). MELAS is described as a neurovascular disorder primarily affecting the brain and blood vessels, but the pathophysiology of the disease is poorly understood. We developed a series of cybrid cell lines at two different mutant loads: 70% and 100% in the nuclear background of a neuroblastoma cell line (SH-SY5Y). We investigated the impact of the mutation on the metabolism and mitochondrial respiratory chain activity of the cybrids. The m.3243A>G mitochondrial mutation induced a metabolic switch towards glycolysis in the neuronal cells and produced severe defects in respiratory chain assembly and activity. We used two strategies to compensate for the biochemical defects in the mutant cells: one consisted of lowering the glucose content in the culture medium, and the other involved the addition of L-arginine. The reduction of glucose significantly shifted the 100% mutant cells towards the wild-type, reaching a 90% mutant level and restoring respiratory chain complex assembly. The addition of L-arginine, a nitric oxide (NO) donor, improved complex I activity in the mutant cells in which the defective NO metabolism had led to a relative shortage of NO. Thus, metabolically induced heteroplasmy shifting and L-arginine therapy may constitute promising therapeutic strategies against MELAS. PMID:22306605

Identification of FASTKD2 compound heterozygous mutations as the underlying cause of autosomal recessive MELAS-like syndrome.

Science.gov (United States)

Yoo, Da Hye; Choi, Young-Chul; Nam, Da Eun; Choi, Sun Seong; Kim, Ji Won; Choi, Byung-Ok; Chung, Ki Wha

2017-07-01

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a condition that affects many parts of the body, particularly the brain and muscles. This study examined a Korean MELAS-like syndrome patient with seizure, stroke-like episode, and optic atrophy. Target sequencing of whole mtDNA and 73 nuclear genes identified compound heterozygous mutations p.R205X and p.L255P in the FASTKD2. Each of his unaffected parents has one of the two mutations, and both mutations were not found in 302 controls. FASTKD2 encodes a FAS-activated serine-threonine (FAST) kinase domain 2 which locates in the mitochondrial inner compartment. A FASTKD2 nonsense mutation was once reported as the cause of a recessive infantile mitochondrial encephalomyopathy. The present case showed relatively mild symptoms with a late onset age, compared to a previous patient with FASTKD2 mutation, implicating an inter-allelic clinical heterogeneity. Because this study is the second report of an autosomal recessive mitochondrial encephalomyopathy patient with a FASTKD2 mutation, it will extend the phenotypic spectrum of the FASTKD2 mutation. Copyright © 2017. Published by Elsevier B.V.

Perfusion status of the stroke-like lesion at the hyperacute stage in MELAS.

Science.gov (United States)

Yeh, Hsu-Ling; Chen, Yen-Kung; Chen, Wei-Hung; Wang, Han-Cheng; Chiu, Hou-Chang; Lien, Li-Ming; Wei, Yau-Huei

2013-02-01

Hypoperfusion on single-photon emission computed tomography (SPECT) of the stroke-like lesion (SLL) at the hyperacute stage of mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) is considered to be a supportive evidence of the mitochondrial angiopathy theory. Our objectives were to examine whether other neuroimages, especially transcranial color-coded sonography (TCCS), done at the hyperacute stage of stroke-like episode (SLE) is consistent with hypoperfusion of the SLL. We reviewed the magnetic resonance imaging (MRI), SPECT, cerebral angiography, and TCCS of a patient with MELAS syndrome, all of which were performed at the hyperacute stage of one SLE. MRI on the 1st day post SLE showed right temporoparietal lesion with vasogenic edema. SPECT on the 2nd day showed focal decreased uptake of technetium-99m hexamethylpropyleneamine oxime ((99m)Tc-HMPAO) in the same region, but cerebral angiography and TCCS on the 3rd day showed increased regional cerebral blood flow (rCBF) and distal arteriole dilation in the same region. TCCS can delineate increased rCBF of the SLL at the hyperacute stage of SLE. We propose that the discrepancy between the decreased (99m)Tc-HMPAO uptake and increased rCBF might be caused by mitochondrial dysfunction. The phenomenon of "hypoperfusion" on SPECT might be caused by cell dysfunction but not decreased rCBF. We suggest that SPECT can be complemented by angiography and TCCS in future studies to delineate the perfusion status of SLLs. Copyright © 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Serial diffusion-weighted imaging in a patient with MELAS and presumed cytotoxic oedema

International Nuclear Information System (INIS)

Wang, X.Y.; Noguchi, K.; Ogawa, S.; Seto, H.; Takashima, S.; Hayashi, N.

2003-01-01

A patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was studied with serial diffusion-weighted MRI (DWI) after stroke-like episodes and the apparent diffusion coefficient (ADC) was measured in an infarct-like lesion. In the acute and subacute stages, the affected area gave high signal on DWI and its ADC was much lower than that in a normal control region. In the chronic stage, the ADC became higher than that in normal brain. We therefore suggest that the stroke-like episodes did not cause vasogenic oedema but were related to energy failure and cytotoxic oedema. (orig.)

Antonio Costa, La mela di Cézanne e l’accendino di Hitchcock. Il senso delle cose nei film

Directory of Open Access Journals (Sweden)

Beatrice Seligardi

2016-05-01

Full Text Available «Sono diecimila persone, forse, che non hanno dimenticato la mela di Cézanne ma sono un miliardo gli spettatori che si ricorderanno dell’accendino di Delitto per delitto» (5. Così Godard recitava all’interno delle Histoire(s du cinéma, e così si apre il saggio di Antonio Costa, prendendone spunto anche per il titolo.

[MELAS syndrome as a differential diagnosis of ischemic stroke].

Science.gov (United States)

Finsterer, J

2009-01-01

Mitochondrial encephalomyopathy, lactacidosis and stroke-like episode (MELAS) syndrome is a phenotypically and genetically heterogeneous mitochondrial disorder with a clinical onset between the first and third decade. The clinical hallmark is the stroke-like-episode, which mimicks ischemic stroke but is usually transient and non-disabling in nature. The morphological equivalent on MRI is a T2-hyperintensity, predominantly over the temporo-parieto-occipital region, not confined to a vascular territory, which is also hyperintense on diffusion weighted imaging and on apparent diffusion coefficient sequences (vasogenic edema, stroke-like lesion). Additional features include seizures, cognitive decline, psychosis, lactic acidosis, migraine, visual impairment, hearing loss, short stature, diabetes, or myopathy. Muscle biopsy typically shows ragged-red fibers, COX-negative fibers, SDH hyperreactivity, and abnormally shaped mitochondria with paracristalline inclusions. The diagnosis is confirmed by demonstration of a biochemical respiratory chain defect or one of the disease-causing mutations, of which 80 % affect the mitochondrial tRNALeu gene.

Environmental impact assessment. Investigation of marine mammals in relation to the establishment of a marine wind farm on Horns Reef

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-02-15

Elsamproject has decided to carry out an environmental impact assessment with the aim to investigate whether the establishment of a marine wind farm on Horns Reef may impact on breeding and non-breeding marine mammals, particularly harbour porpoise Phocoena phocoena and common seal Phoca vitulina. The marine mammals of the northern part of the German Bight can be characterised by a regular occurrence of harbour porpoise and common seal throughout the year, an irregular occurrence of grey seal Halichoerus grypus and white-beaked dolphin Lagenorhynchus albirostris and rare occurrences of white-sided dolphin Lagenorhynchus acutus, minke whale Balaenoptera acutorostrata, sperm whale Physeter macrocephalus, long-finned pilot whale Globicephala melas and killer whale Orcinus orca. The environment impact assessment therefore focuses on the evaluation of the possible effects on harbour porpoise and common seal. The investigation constitutes the first phase of a before-after-control-impact (BACI) analysis of the occurrence of harbour porpoise before, during and after the construction of the wind farm. (au)

Trace elements in two odontocete species (Kogia breviceps and Globicephala macrorhynchus) stranded in New Caledonia (South Pacific)

International Nuclear Information System (INIS)

Bustamante, P.; Garrigue, C.; Breau, L.; Caurant, F.; Dabin, W.; Greaves, J.; Dodemont, R.

2003-01-01

Trace elements in whales on New Caledonia beaches are below levels for concern. - Liver, muscle and blubber tissues of two short-finned pilot whales (Globicephala macrorhynchus) and two pygmy sperm whales (Kogia breviceps) stranded on the coast of New Caledonia have been analysed for 12 trace elements (Al, Cd, Co, Cr, Cu, Fe, organic and total Hg, Mn, Ni, Se, V, and Zn). Liver was shown to be the most important accumulating organ for Cd, Cu, Fe, Hg, Se, and Zn in both species, G. macrorhynchus having the highest Cd, Hg, Se and Zn levels. In this species, concentrations of total Hg are particularly elevated, reaching up to 1452 μg g -1 dry wt. Only a very low percentage of the total Hg was organic. In both species, the levels of Hg are directly related to Se in liver. Thus, a molar ratio of Hg:Se close to 1.0 was found for all specimens, except for the youngest K. breviceps. Our results suggest that G. macrorhynchus have a physiology promoting the accumulation of high levels of naturally occurring toxic elements. Furthermore, concentrations of Ni, Cr and Co are close to or below the detection limit in the liver and muscles of all specimens. This suggests that mining activity in New Caledonia, which typically elevates the levels of these contaminants in the marine environment, does not seem to be a significant source of contamination for these pelagic marine mammals

Tc-99m ECD brain SPECT in MELAS syndrome and mitochondrial myopathy: comparison with MR findings

International Nuclear Information System (INIS)

Park, Sang Joon; Ryu, Young Hoon; Jeon, Tae Joo; Kim, Jai Keun; Nam, Ji Eun; Yoon, Pyeong Ho; Yoon, Choon Sik; Lee, Jong Doo

1998-01-01

We evaluated brain perfusion SPECT findings of MELAS syndrome and mitochondrial myopathy in correlation with MR imaging in search of specific imaging features. Subjects were five patients (four females and one male; age range, 1 to 25 year) who presented with repeated stroke like episodes, seizures or developmental delay or asymptomatic but had elevated lactic acid in CSF and serum. Conventional non-contrast MR imaging and Tc-99m-ethyl cysteinate dimer (ECD) brain perfusion SPECT were performed and imaging features were analyzed. MRI demonstrated increased T2 signal intensities in the affected areas of gray and white matters mainly in the parietal (4/5) and occipital lobes (4/5) and in the basal ganglia (1/5), which were not restricted to a specific vascular territory. SPECT demonstrated decreased perfusion in the corresponding regions of MRI lesions. In addition, there were perfusion defects in parietal (1 patient), temporal (2), and frontal (1) lobes and basal ganglia (1) and thalami (2). In a patient with mitochondrial myopathy who had normal MRI, decreased perfusion was noted in left parietal area and bilateral thalami. Tc-99m ECD SPECT imaging in patients with MELAS syndrome and mitochondrial myopathy showed hypoperfusion of parieto-occipital cortex, basal ganglia, thalamus and temporal cortex, which were not restricted to a specific vascular territory. There were no specific imaging features on SPECT. The significance of abnormal perfusion on SPECT without corresponding MR abnormalities needs to be evaluated further in larger number of patients

Multimodal imaging-monitored progression of stroke-like episodes in a case of MELAS syndrome.

Science.gov (United States)

Namer, Izzie Jacques; Wolff, Valérie; Dietemann, Jean-Louis; Marescaux, Christian

2014-03-01

We report imaging findings during, between, and after 2 stroke-like episodes in a 45-year-old woman with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome with an A32243G mitochondrial mutation 6 years before. In November 2010, for a first episode, she showed mixed aphasia with logorrhea, disinhibition, agitation, euphoria, and a large left temporoparietal lesion. Symptomatology progressively regressed under L-arginine treatment. She was readmitted in June 2011 for a second episode with great anxiety, disorientation, impaired face recognition, worsening mixed aphasia, and a new right temporal lesion. After additional L-carnitine treatment, she remained without relapse for 14 months.

O papel de Rhizoctonia spp. binucleadas na indução de resistência a mela da soja = The role of binucleate Rhizoctonia spp. inducing resistance to the soybean foliar blight

Directory of Open Access Journals (Sweden)

Marco Antonio Basseto

2008-04-01

Full Text Available O papel de Rhizoctonia spp. binucleadas (RBN, no biocontrole de doenças causadas por R. solani Kühn em várias culturas, tem sido relatado na literatura. No entanto, não há informação, no Brasil, sobre o potencial de RBN como agentes de biocontrole contradoenças causadas por Rhizoctonia na soja. A hipótese testada foi de que isolados de RBN podem induzir resistência na soja contra a mela, causada por R. solani do grupo de anastomose (AG 1 IA. Desta forma, o objetivo deste trabalho foi avaliar isolados de RBN, obtidos de amendoim, feijão e soja quanto à capacidade de induzir resistência na soja contra a mela, em condições de casa de vegetação. Esta pesquisa evidencia a ação de RBN na indução de resistência em plantas de soja contra a mela. Entretanto, a manifestação e a efetividade do fenômeno de indução de resistência são dependentes da época de cultivo da soja.The role of non-pathogenic binucleate Rhizoctonia spp. (BNR onthe biocontrol of diseases caused by R. solani on many crops has been reported in the literature. However, in Brazil, there is no information about the potential of BNR as biocontrol agents against Rhizoctonia diseases on soybean. On this research we tested thehypothesis that BNR can induce resistance on soybean against the foliar blight caused by R. solani anastomosis group (AG 1 IA. Thus, the objective of this research was to evaluate BNR isolates isolated from peanuts, snapbeans and soybean according to their ability forinducing resistance on soybean against the foliar blight disease, under greenhouse conditions. This research evidenced the role of BNR inducing resistance on soybeans against the foliar blight. However, both the occurrence and effectiveness of the phenomenon of induced resistance are dependent on the soybean cultivation season.

Static inflation and deflation pressure–volume curves from excised lungs of marine mammals

Science.gov (United States)

Fahlman, Andreas; Loring, Stephen H.; Ferrigno, Massimo; Moore, Colby; Early, Greg; Niemeyer, Misty; Lentell, Betty; Wenzel, Frederic; Joy, Ruth; Moore, Michael J.

2011-01-01

SUMMARY Excised lungs from eight marine mammal species [harp seal (Pagophilus groenlandicus), harbor seal (Phoca vitulina), gray seal (Halichoerus grypush), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas) and harbor porpoise (Phocoena phocoena)] were used to determine the minimum air volume of the relaxed lung (MAV, N=15), the elastic properties (pressure–volume curves, N=24) of the respiratory system and the total lung capacity (TLC). Our data indicate that mass-specific TLC (sTLC, l kg–1) does not differ between species or groups (odontocete vs phocid) and agree with that estimated (TLCest) from body mass (Mb) by applying the equation: TLCest=0.135 Mb0.92. Measured MAV was on average 7% of TLC, with a range from 0 to 16%. The pressure–volume curves were similar among species on inflation but diverged during deflation in phocids in comparison with odontocetes. These differences provide a structural basis for observed species differences in the depth at which lungs collapse and gas exchange ceases. PMID:22031747

Cetacean diversity and distribution in the coast of Gipuzkoa and adjacent waters, southeastern Bay of Biscay

Directory of Open Access Journals (Sweden)

MARCOS, E., SALAZAR, J.M., STHEPANIS, R. de

2010-01-01

Full Text Available Desde el año 2003, se ha realizado un seguimiento continuo a las poblaciones de cetáceos de la costa guipuzcoana, siguiendo los protocolos de muestreo de cetáceos en mar de la Sociedad Española de Cetáceos. Se ha estudiado la diversidad, la densidad, la distribución espacial y temporal de estas especies. Los resultados indican la presencia de 12 especies de cetáceos en el área, y la importancia de la misma para cinco de ellas, especialmente para el delfín mular (Tursiops truncatus. El delfín común (Delphinus delphis, el calderon de aleta larga (Globicephala melas, el delfín listado (Stenella coeruleoalba y el cifio de cuvier (Ziphius cavirostris son especies altamente representadas en el área. Se han definido las principales áreas de distribución de estas especies con el fin de dar los primeros pasos para la creación de un Área Marina Protegida en el área.

Kidney involvement in MELAS syndrome: Description of 2 cases.

Science.gov (United States)

Alcubilla-Prats, Pau; Solé, Manel; Botey, Albert; Grau, Josep Maria; Garrabou, Glòria; Poch, Esteban

2017-04-21

MELAS syndrome -myopathy, encephalopathy, lactic acidosis and stroke-like episodes- is a maternally-inherited mitochondrial cytopathy related to several mitochondrial DNA mutations, with the A3243G mutation in tRNA Leu gene being the most frequent of them. Apart from its typical symptomatology, patients usually exhibit a maternally-inherited history of neurosensory deafness and insulin-dependent type 2 diabetes mellitus (T2DM). Recent studies have shown that few patients carrying a A3243G mutation also suffer from renal dysfunction, usually in form of focal segmental glomerulosclerosis (FSGS). In this study we examine kidney involvement in 2 unrelated patients with a A3243G mutation by genetic testing. Both have a maternally-inherited neurosensory deafness and insulin-dependent T2DM. A renal biopsy was performed in both patients. One patient developed nephrotic proteinuria and renal insufficiency, with FSGS findings being observed in the kidney biopsy, whereas the other suffered from mild proteinuria and renal insufficiency, with non-specific glomerular changes. The presence of FSGS or other kidney involvement accompanied by hereditary neurosensory deafness and T2DM could be suggestive of a A3243G tRNA Leu mutation and should prompt a genetic testing and an evaluation of potential extrarenal involvement. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Diabetes and hypertension: public awareness and lifestyle-findings of a health mela

International Nuclear Information System (INIS)

Rafique, G.; Khuwaja, A.K.

2003-01-01

Objective: To determine the frequencies of diabetes, hypertension and their established lifestyle risk factors and to assess the level of awareness about diabetes and hypertension amongst persons attending a health mela at the Aga Khan University Hospital (AKUH), Karachi. Subjects and methods: A total of 264 participants were administered structured questionnaire to obtain demographic data and perceptions about diabetes and hypertension after taking verbal informed consent. Height, weight, blood pressure and random blood glucose were measured. Results: Overall frequency of type-2 diabetes was 13.5%, impaired glucose tolerance (IGT) 8.3% and hypertension 24%. Frequency of diabetes and hypertension in both men and women increased with increasing age (p< .001) and body mass index (p=0.02). Over half the men and women with type 2 diabetes (53% and 57% respectively) and 42% men and 60% women with IGT also had hypertension. Diabetes and hypertension were correctly defined by 52% and 37% subjects respectively and this was significantly associated with educational level (p=.001). Lack of physical exercise was observed in 59% participants, while 53.6% men and 67.5% women were overweight/obese. As compared to women, men used more additional salt (p = 0.03) and had more outside meals (p<0.001) and lack of physical exercise was observed in 59% participants, while 53.6% men and 67% women were overweight/obese. As compared to women, men used more additional salts (p=0.03) and had a more outside meals (p<0.001) and snacks (p=0.01). Conclusion: High frequencies of diabetes, hypertension, obesity, unhealthy nutrition and lack of exercise were observed in the study population. Emphasis on health education is needed to increase public awareness of the warming signs and risk factors of these common conditions. (author)

Kimberlite emplacement time and duration of kimberlite magmatism in the Zimnii Bereg diamond-diferrous district, Arkhangelsk Region: Rb-Sr age of kimberlite sills, Mela River

International Nuclear Information System (INIS)

Pervov, V.A.; Larchenko, V.A.; Minchenko, G.V.; Stepanov, V.P.; Bogomolov, E.S.; Levskij, L.K.; Sergeev, S.A.

2006-01-01

The Rb-Sr isotope data for kimberlites and carbonate-rich sills of the Mela River were obtained for identifying the age and duration of magmatism in the Zimnii Bereg district of the Archangelsk region. It is shown that estimated age of the kimberlite (366.4 mln. years) falls in the age range corresponding to the main phase of alkaline magmatism in the Kola Peninsula (410-362 mln. years) [ru

Postmortem evidence of interactions of bottlenose dolphins (Tursiops truncatus) with other dolphin species in south-west England.

Science.gov (United States)

Barnett, J; Davison, N; Deaville, R; Monies, R; Loveridge, J; Tregenza, N; Jepson, P D

2009-10-10

Reports of violent interactions between bottlenose dolphins (Tursiops truncatus) and harbour porpoises (Phocoena phocoena) in the coastal waters of the UK are well documented. Examination of stranded cetaceans by the Cornwall Wildlife Trust Marine Strandings Network and the UK Cetacean Strandings Investigation Programme has indicated that seven animals, of four other species, found stranded in south-west England, had pathology consistent with bottlenose dolphin interaction, including two juvenile and two adult common dolphins (Delphinus delphis), one juvenile pilot whale (Globicephala melas), one juvenile Risso's dolphin (Grampus griseus) and one adult striped dolphin (Stenella coeruleoalba). Although recorded traumatic lesions were often not as severe as those found in harbour porpoises, it is probable that the interactions did contribute to stranding and/or death in all four of the juvenile animals examined. Furthermore, analysis of photographs taken before establishment of the Marine Strandings Network revealed rake (teeth) marks consistent with bottlenose dolphin interaction on one stranded common dolphin in 1992. A number of causes have been suggested for these interactions in harbour porpoises stranded in the UK and it is possible that any combination of these factors may also be implicated in the cases described in this report.

Caracterização espectral de áreas de gramíneas forrageiras infectadas com a doença "mela-das-sementes da braquiária" por meio de imagens CCD/CBERS-2 Spectral characterization of forage grasses infected with the disease "mela-das-sementes da braquiária" through CCD/CDBERS -2 images

Directory of Open Access Journals (Sweden)

José C. Rosatti

2006-12-01

Full Text Available Imagens CCD/CBERS-2, nas bandas espectrais CCD2, CCD3 e CCD4, dos anos de 2004 e 2005, de Mirante do Paranapanema - SP, foram transformadas em reflectância de superfície usando o modelo 5S de correção atmosférica e normalizadas radiometricamente. O objetivo principal foi caracterizar espectralmente áreas de pastagens de Brachiaria brizantha em fase de florescimento, isentas e infectadas com a doença "mela-das-sementes da braquiária", possibilitando a sua detecção por meio da comparação entre os valores de reflectância de superfície denominada de Fator de Reflectância Bidirecional de Superfície (FRBS. Teve-se, também, o objetivo de avaliar a eficácia das imagens CCD/CBERS-2 para a obtenção de respostas espectrais de pastagens. Os dosséis sadios e doentes da Brachiaria brizantha foram identificados por meio da análise dos valores de reflectância e dos dados observados no Índice de Estresse Hídrico Acumulativo Relativo da Cultura (ACWSI obtidos na área de estudo. Os resultados indicaram que as principais diferenças foram a diminuição da reflectância na banda CCD3 e o aumento da reflectância na banda CCD4 nas áreas doentes. A metodologia empregada com o uso de dados do sensor CCD/CBERS-2, associados ao ACWSI, mostrou-se eficaz para discriminar dosséis infectados com a "mela-das-sementes da braquiária".CCD/CBERS-2 images in the spectral bands of CCD2, CCD3 and CCD4 of the years 2004 and 2005, from Mirante do Paranapanema - SP (Brazil, were transformed into surface reflectance images using the 5S atmospheric correction model and radiometrically normalized. The main objective was to spectrally characterize pastures of Brachiaria brizantha in the flowering phase, exempt and infected with the disease "mela-das-sementes da braquiária" making it possible its detection through the comparison among the SBRF - Surface Bidirectional Reflectance Factor values. At the same time, it was aimed to evaluate the effectiveness of the

Mass-gathering Events: The Public Health Challenge of the Kumbh Mela 2013.

Science.gov (United States)

Dwivedi, Suresh; Cariappa, Mudera P

2015-12-01

Mass-gathering (MG) events pose challenges to the most adept of public health practitioners in ensuring the health safety of the population. These MGs can be for sporting events, musical festivals, or more commonly, have religious undertones. The Kumbh Mela 2013 at Allahabad, India may have been the largest gathering of humanity in history with nearly 120 million pilgrims having thronged the venue. The scale of the event posed a challenge to the maintenance of public health security and safety. A snapshot of the experience of managing the hygiene and sanitation aspects of this mega event is presented herein, highlighting the importance of proactive public health planning and preparedness. There having been no outbreaks of disease is vindication of the steps undertaken in planning and preparedness, notwithstanding obvious limitations of unsanitary behaviors and traditional beliefs of those attending the festival. The evident flaw on post-event analyses was the failure to cater adequately for environmental mopping-up operations after the festival. Besides, a system of real-time monitoring of disease and morbidity patterns, harnessing low cost technology alternatives, should be planned for at all such future events.

Severidade da mela da soja causada por Rhizoctonia solani AG-1 IA em função de doses de potássio Severity of hte foliar blight of the soylean caused by Rhizoctonia solani AG-1 IA infunction of doses of potassium

Directory of Open Access Journals (Sweden)

Marco Antonio Basseto

2007-03-01

Full Text Available O fungo Rhizoctonia solani pertencente ao grupo de anastomose 1 IA (AG-1 IA é um dos patógenos mais importantes afetando a cultura da soja no Brasil. Este fungo causa queima da folha e/ou mela em soja, para a qual medidas de manejo cultural são consideradas alternativas importantes para controle antes do estabelecimento da doença. Há evidências de que a adubação potássica diminui substancialmente a severidade dos sintomas de várias doenças da soja como a queima foliar (Cercospora kikuchii, a seca da haste e da vagem (Phomopsis phaseoli var. sojae e o cancro da haste (Diaporthe phaseolorum f. sp. meridionalis. Apesar das evidências do efeito do potássio no controle de várias doenças da soja, não há informação na literatura sobre o efeito desse nutriente no controle da mela. A hipótese testada foi que a mela da soja pode ser controlada através de incrementos na adubação potássica. De maneira geral, concluiu-se que, sob condições de casa de vegetação, o incremento de K no solo não resultou no controle da mela da soja. É necessário, entretanto, confirmar esta observação conduzindo-se experimentos sob condições de campo, podendo-se incluir a avaliação do efeito da doença sob aspectos da produção.The fungus Rhizoctonia solani, belonging to anastomosis group 1IA (AG-1 IA is one of the most important pathogens affecting soybean in Brazil. This fungus causes aerial or foliar blight of soybean, and cultural measures are thought as important choices for the control before the establishment of the disease. Based on evidences that potassium amendments can substantially reduce the severity of several soybean diseases such as Cercospora leaf blight (Cercospora kikuchii, pod and stem blight (Phomopsis phaseoli var. sojae and stem canker (Diaporthe phaseolorum f. sp. meridionalis. Despite all evidence, there is no information in the literature about the effect of potassium controlling the soybean foliar blight. The

Radiolabeled Cu-ATSM as a novel indicator of overreduced intracellular state due to mitochondrial dysfunction: studies with mitochondrial DNA-less ρ0 cells and cybrids carrying MELAS mitochondrial DNA mutation

International Nuclear Information System (INIS)

Yoshii, Yukie; Yoneda, Makoto; Ikawa, Masamichi; Furukawa, Takako; Kiyono, Yasushi; Mori, Tetsuya; Yoshii, Hiroshi; Oyama, Nobuyuki; Okazawa, Hidehiko; Saga, Tsuneo; Fujibayashi, Yasuhisa

2012-01-01

Objectives: Radiolabeled Cu-diacetyl-bis (N 4 -methylthiosemicarbazone) ( ⁎ Cu-ATSM), including 60/62/64 Cu-ATSM, is a potential imaging agent of hypoxic tumors for positron emission tomography (PET). We have reported that ⁎ Cu-ATSM is trapped in tumor cells under intracellular overreduced states, e.g., hypoxia. Here we evaluated ⁎ Cu-ATSM as an indicator of intracellular overreduced states in mitochondrial disorders using cell lines with mitochondrial dysfunction. Methods: Mitochondrial DNA-less ρ 0 206 cells; the parental 143B human osteosarcoma cells; the cybrids carrying mutated mitochondria from a patient of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) (2SD); and that carrying wild-type one (2SA) were used. Cells were treated under normoxia or hypoxia, and 64 Cu-ATSM uptake was examined to compare it with levels of biological reductant NADH and NADPH. Results: ρ 0 206 cells showed higher 64 Cu-ATSM uptake than control 143B cells under normoxia, whereas 64 Cu-ATSM uptake was not significantly increased under hypoxia in ρ 0 206 cells. Additionally, 64 Cu-ATSM uptake showed correlate change to the NADH and NADPH levels, but not oxygenic conditions. 2SD cells showed increased 64 Cu-ATSM uptake under normoxia as compared with the control 2SA, and 64 Cu-ATSM uptake followed NADH and NADPH levels, but not oxygenic conditions. Conclusions: 64 Cu-ATSM accumulated in cells with overreduced states due to mitochondrial dysfunction, even under normoxia. We recently reported that 62 Cu-ATSM-PET can visualize stroke-like episodes maintaining oxygen supply in MELAS patients. Taken together, our data indicate that ⁎ Cu-ATSM uptake reflects overreduced intracellular states, despite oxygenic conditions; thus, ⁎ Cu-ATSM would be a promising marker of intracellular overreduced states for disorders with mitochondrial dysfunction, such as MELAS, Parkinson's disease and Alzheimer's disease.

Correction of the consequences of mitochondrial 3243A>G mutation in the MT-TL1 gene causing the MELAS syndrome by tRNA import into mitochondria.

Science.gov (United States)

Karicheva, Olga Z; Kolesnikova, Olga A; Schirtz, Tom; Vysokikh, Mikhail Y; Mager-Heckel, Anne-Marie; Lombès, Anne; Boucheham, Abdeldjalil; Krasheninnikov, Igor A; Martin, Robert P; Entelis, Nina; Tarassov, Ivan

2011-10-01

Mutations in human mitochondrial DNA are often associated with incurable human neuromuscular diseases. Among these mutations, an important number have been identified in tRNA genes, including 29 in the gene MT-TL1 coding for the tRNA(Leu(UUR)). The m.3243A>G mutation was described as the major cause of the MELAS syndrome (mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes). This mutation was reported to reduce tRNA(Leu(UUR)) aminoacylation and modification of its anti-codon wobble position, which results in a defective mitochondrial protein synthesis and reduced activities of respiratory chain complexes. In the present study, we have tested whether the mitochondrial targeting of recombinant tRNAs bearing the identity elements for human mitochondrial leucyl-tRNA synthetase can rescue the phenotype caused by MELAS mutation in human transmitochondrial cybrid cells. We demonstrate that nuclear expression and mitochondrial targeting of specifically designed transgenic tRNAs results in an improvement of mitochondrial translation, increased levels of mitochondrial DNA-encoded respiratory complexes subunits, and significant rescue of respiration. These findings prove the possibility to direct tRNAs with changed aminoacylation specificities into mitochondria, thus extending the potential therapeutic strategy of allotopic expression to address mitochondrial disorders.

Movements and dive patterns of short-finned pilot whales (Globicephala macrorhynchus) released from a mass stranding in the Florida Keys

Science.gov (United States)

Wells, Randall S.; Fougeres, Erin M.; Cooper, Arthur G.; Stevens, Robert O.; Brodsky, Micah; Lingenfelser, Robert; Dold, Chris; Douglas, David C.

2013-01-01

Short-finned pilot whales (Globicephala macrorhynchus) are among the most common cetaceans to engage in mass strandings in the southeastern United States. Because these are primarily pelagic, continental shelf-edge animals, much of what is known about this species has derived from mass stranding events. Post-release monitoring via satellite-linked telemetry was conducted with two adult males determined on-site to be healthy, and released directly from a mass stranding of 23 pilot whales in May 2011, near Cudjoe Key, Florida. Tracking provided an opportunity to evaluate the decision for immediate release vs rehabilitation, and to learn more about the lives of members of this difficult-to-study species in the wild. The two pilot whales remained together for at least 16 d before transmissions from one pilot whale (Y-404) ceased. Dive patterns and travel rates suggested that Y-404’s condition deteriorated prior to signal loss. Pilot Whale Y-400 was tracked for another 51 d, moving from the Blake Plateau to the Greater Antilles, remaining in the Windward Passage east of Cuba for the last 17 d of tracking. Once he reached the Antilles, Y-400 remained in high-relief habitat appropriate for the species and made dives within or exceeding the reported range for depth and duration for this species, following expected diel patterns, presumably reflecting continued good health. Telemetry data indicate that he made at least one dive to 1,000 to 1,500 m, and several dives lasted more than 40 min. Although the fates of the two released pilot whales may have been different, the concept of evaluating health and releasing individuals determined to be healthy at the time of stranding appears to have merit as an alternative to bringing all members of mass-stranded pilot whale groups into rehabilitation.

Produção de carvão ativado a partir de bagaço e melaço de canade- açúcar = Production of granular activated carbons from sugar cane bagasse and molasses

Directory of Open Access Journals (Sweden)

Gilberto da Cunha Gonçalves

2006-01-01

Full Text Available Carvões ativados foram preparados a partir de diferentes misturas de bagaço e melaço de cana-de-açúcar. A relação mássica bagaço:melaço variou de 1:0 a 1:2. Cada mistura foi prensada, formando pellets, os quais foram submetidos a uma pirólise sob fluxo de 150 mL·min-1 de N2, a 850°C, por 1 hora. Os carvões pirolisados foram ativados comCO2, sob fluxo de 75 mL·min-1, a 850°C, durante 30 min. A caracterização dos carvões ativados foi realizada pela análise de isotermas de adsorção física de N2 (77 K, pH e descoloração de soluções de melaço de cana (1% p/v. O rendimento médio dos carvõesativados foi de 23% em relação aos pellets iniciais. A área superficial específica dos carvões variou de 272 a 455 m2·g-1 com predominância de micro e mesoporos. Os carvões ativados preparados com pequena adição de melaço apresentaram-se tão eficientes na descoloração quanto um carvão ativado comercial, utilizado como referência.Activated carbons were prepared from mixtures of sugar cane bagasse and molasses in bagasse:molasses mass ratios from 1:0 to 1:2. The mixture was pressed to form pellets, and pyrolyzed under N2 flow of 150 mL·min-1, at 850°C, for 1 hour. The pyrolyzed carbons were activated with CO2, under the flow of 75 mL·min-1 at 850°C for 30 min. The activated carbons were characterized by an analysis of nitrogen adsorption isotherms (77 K, pH, and solutions decolorization of sugar cane molasses (1% w/v. Results showed that the activated carbons presented yield of 23% in relation to the initial pellets, surface areas from 272 to 455 m2·g-1, and that micro and mesopores were predominant in the pore size distribution. Activated carbons made with a smaller amount of molasses in the mixture were as efficient in the decolorization as a commercial reference carbon.

Using mobile technology to optimize disease surveillance and healthcare delivery at mass gatherings: a case study from India's Kumbh Mela.

Science.gov (United States)

Kazi, Dhruv S; Greenough, P Gregg; Madhok, Rishi; Heerboth, Aaron; Shaikh, Ahmed; Leaning, Jennifer; Balsari, Satchit

2017-09-01

Planning for mass gatherings often includes temporary healthcare systems to address the needs of attendees. However, paper-based record keeping has traditionally precluded the timely application of collected clinical data for epidemic surveillance or optimization of healthcare delivery. We evaluated the feasibility of harnessing ubiquitous mobile technologies for conducting disease surveillance and monitoring resource utilization at the Allahabad Kumbh Mela in India, a 55-day festival attended by over 70 million people. We developed an inexpensive, tablet-based customized disease surveillance system with real-time analytic capabilities, and piloted it at five field hospitals. The system captured 49 131 outpatient encounters over the 3-week study period. The most common presenting complaints were musculoskeletal pain (19%), fever (17%), cough (17%), coryza (16%) and diarrhoea (5%). The majority of patients received at least one prescription. The most common prescriptions were for antimicrobials, acetaminophen and non-steroidal anti-inflammatory drugs. There was great inter-site variability in caseload with the busiest hospital seeing 650% more patients than the least busy hospital, despite identical staffing. Mobile-based health information solutions developed with a focus on user-centred design can be successfully deployed at mass gatherings in resource-scarce settings to optimize care delivery by providing real-time access to field data. © The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health.

Cetacean records along São Paulo state coast, Southeastern Brazil

Directory of Open Access Journals (Sweden)

Marcos César de Oliveira Santos

2010-06-01

Full Text Available The São Paulo state (SP coast (23º18'S, 44º42'W; 25º14'S, 48º01'W is of approximately 600 km in length, bordering the Western Atlantic Ocean, in southeastern Brazil. Cetacean sightings and strandings have long been observed throughout this area. Scattered data from scientific publications, skeletal remains in museums, photographs and articles from newspaper files, universities and aquaria have been organised and updated since 1993. Field investigations on strandings and sightings have also been conducted. A total of 29 cetacean species have been recorded, including 7 baleen whales (Mysticeti and 22 toothed whales (Odontoceti, as follows: Balaenoptera physalus, B. borealis, B. edeni, B. acutorostrata, B. bonaerensis, Megaptera novaeangliae, Eubalaena australis, Physeter macrocephalus, Kogia breviceps, K. sima, Berardius arnuxii, Mesoplodon europaeus, M. mirus, Ziphius cavirostris, Orcinus orca, Feresa attenuata, Globicephala melas, G. macrorhynchus, Pseudorca crassidens, Delphinus capensis, Lagenodelphis hosei, Steno bredanensis, Tursiops truncatus, Stenella frontalis, S. longirostris, S. coeruleoalba, Lissodelphis peronii, Sotalia guianensis and Pontoporia blainvillei. Several species have been observed only once and include strays from their areas of common distribution, as well as species with known preferences for offshore distribution. Others, such as P. blainvillei and S. guianensis, are common coastal dwellers year-round. Z. cavirostris, P. crassidens and L. hosei are reported for the first time on the SP coast.A costa do Estado de São Paulo (SP (23º18'S, 44º42'O; 25º14'S, 48º01'O apresenta aproximadamente 600 km de extensão voltada para o Oceano Atlântico Ocidental no sudeste do Brasil. Registros de encalhes e de avistamentos de cetáceos vêm sendo realizados ao longo desse litoral. Desde 1993, dados obtidos em literatura científica, material osteológico encontrado em museus, fotografias e artigos de arquivos de jornais

Reação de cultivares de soja à mela (Thanatephorus cucumeris em campo em dois estádios de desenvolvimento das plantas Field reaction of soybean cultivars to rhizoctonia aerial blight (Thanatephorus cucumeris at two growth stages

Directory of Open Access Journals (Sweden)

Kátia de Lima Nechet

2008-09-01

Full Text Available A mela, causada pelo fungo Thanatephorus cucumeris, é uma das principais doenças da cultura da soja no estado de Roraima. O objetivo deste trabalho foi avaliar a reação de 15 cultivares de soja à mela em condições de cerrado em Roraima. Os parâmetros avaliados foram a porcentagem de área foliar infectada (AFI no estádio R.5.5 e a porcentagem de vagens com sintoma de mela (VM no estádio R.6. Houve diferença significativa entre as cultivares testadas segundo o teste de Fisher LSD a 1% de probabilidade nas duas avaliações. A AFI variou de 1,5% (cv. Padre a 62% (cv.BR-36 e a VM de 8% (cv.UFV-9 e cv. Juçara a 55% (cv. BR-36. A correlação entre as duas avaliações foi significativa e positiva.Rhizoctonia aerial blight (RAB, caused by the fungus Thanatephorus cucumeris is one of the most damaging diseases of soybean at Roraima, Brazil. The objective of this study was to evaluate the reaction of 15 soybean cultivars to RAB in a cerrado (savannah ecosystem in the state of Roraima. The percentage of foliar area infected (FAI and the percentage of pods with disease symptoms (WP were evaluated on soybean plants at R.5.5 and R.6 growth stages, respectively. There were significative differences among cultivars tested based on Fisher LSD test in both evaluations. The FAI ranged from 1.5% (cv. Padre to 62% (cv. BR-36 and WP from 8% (cv. UFV-9 and cv. Juçara to 55 % (cv. BR-36. Significative and positive correlation was observed between the evaluations.

Fermentação alcoólica de substrato amiláceo e hidrolisado enriquecido com melaço de cana Alcoholic fermentation of starchy hidrolisated substrate with sugar cane residue

Directory of Open Access Journals (Sweden)

Lizandra Bringhenti

2007-04-01

Full Text Available A farinha constitui um dos principais produtos da mandioca, e seu uso é muito difundido em todo o País. Durante o processamento da mandioca para a obtenção da farinha é gerado um resíduo sólido proveniente da decantação da manipueira, o qual é composto essencialmente por amido. Diante da importância do aproveitamento de resíduos agroindústrias para a geração de energia e como fonte de renda para as empresas, com este trabalho objetivou-se avaliar o efeito da adição de melaço (resíduo da produção de açúcar de cana no preparo de soluções de amido para hidrólise enzimática e fermentação alcoólica. Os resultados obtidos demonstraram que a adição de melaço no resíduo amiláceo inicial em doses a partir de 10% levou a um aumento no teor de açúcares no mosto promovendo um aumento de 112% na produção de etanol, em relação ao substrato sem aditivo. Contudo, a seleção de leveduras adaptadas ao substrato faz-se necessária para um melhor rendimento em etanol.The cassava flour is a one of most important commercial product of cassava industries. During the cassava flour processing is obtained a solid residue from 'manipueira' decantation, which is characterized by high level of starch. Due the importance of the residue usage as energy source and income product for industries this work had as purpose to evaluate the addition of sugarcane residue (melaço as supplementary raw material in hydrolysis and fermentation process of cassava starch solution for ethanol production. The results showed that the increase of sugarcane residue percentage in initial solution (> 10% caused the increase of sugar concentration in must and high ethanol yield (increase of 112% when compared with substrate the without sugarcane residue. The yeast selection and substrate adaptation is necessary for increase of ethanol production from cassava starch residue.

MODELOS INTEGRAL E DE PONTO CRÍTICO PARA ESTIMAR DANOS NO RENDIMENTO E SEUS COMPONENTES PELA MELA NA CULTURA DO FEIJOEIRO

Directory of Open Access Journals (Sweden)

Felipe Rafael Garcés Fiallos

2014-04-01

Full Text Available Atualmente não existem estudos sobre os danos ocasionados por Rhizoctonia solani Khun [teleomorfo Thanatephorus cucumeris (Frank Donk] nos componentes de rendimento do feijoeiro (Phaseolus vulgaris L., pelo que o objetivo deste trabalho foi quantificar a redução no rendimento de grãos e seus componentes de rendimento causados pela infecção natural de mela, em diferentes materiais genéticos de feijão, na safra agrícola de verão 2011, no município de Quevedo, Los Rios, Equador. O delineamento experimental foi em blocos casualizados, com sete tratamentos e quatro repetições. Utilizou-se as linhas Cf4 0-0-2-1, Cf6 0-0-4-9, Cf6 0-0-4-8, SER 03 e SER 08, e duas variedades estrangeiras FTS Soberano e BRS Valente. Foram quantificadas a incidência (% e severidade em percentagem e número de lesões folíolo-1, sendo esses valores obtidos integralizados na área abaixo da curva de progresso da doença (AACPD. Também foi quantificado o número de lesões folíolo-1 durante os estágios reprodutivos R7 e R8. Após a colheita, foi quantificado o número de nós, vagens e grãos por planta e de grãos por vagem por planta, assim como rendimento (kg ha-1. Para estimar os danos causados pela doença foram utilizados os modelos de ponto crítico e integral, realizando a análise de regressão entre a intensidade da doença (variáveis independentes, e o rendimento de grãos e seus componentes (variáveis dependentes, obtendo-se as equações da função de dano. Os resultados da presente pesquisa mostraram que os modelos de ponto crítico e integral são uma ferramenta importante para estimar danos pela mela nos componentes de rendimento, sendo mais evidente no número de grãos por plantas (p<0.01.

[Morphological signs of mitochondrial cytopathy in skeletal muscles and micro-vessel walls in a patient with cerebral artery dissection associated with MELAS syndrome].

Science.gov (United States)

Sakharova, A V; Kalashnikova, L A; Chaĭkovskaia, R P; Mir-Kasimov, M F; Nazarova, M A; Pykhtina, T N; Dobrynina, L A; Patrusheva, N L; Patrushev, L I; Protskiĭ, S V

2012-01-01

Skin and muscles biopsy specimens of a patient harboring A3243G mutation in mitochondrial DNA, with dissection of internal carotid and vertebral arteries, associated with MELAS were studied using histochemical and electron-microscopy techniques. Ragged red fibers, regional variability of SDH histochemical reaction, two types of morphologically atypical mitochondria and their aggregation were found in muscle. There was correlation between SDH histochemical staining and number of mitochondria revealed by electron microscopy in muscle tissue. Similar mitochondrial abnormality, their distribution and cell lesions followed by extra-cellular matrix mineralization were found in the blood vessel walls. In line with generalization of cytopathy process caused by gene mutation it can be supposed that changes found in skin and muscle microvessels also exist in large cerebral vessels causing the vessel wall "weakness", predisposing them to dissection.

Mixotrophic growth of Nostoc sp. on glucose, sucrose and sugarcane molasses for phycobiliprotein production = Crescimento mixotrófico de Nostoc sp. Glucose, sacarose e melaço de cana-de-açúcar foram testados como substratos para produção de biomassa e ficobiliproteinas

Directory of Open Access Journals (Sweden)

Maria Helena Pimenta Pinotti

2007-01-01

Full Text Available Glucose, sacarose, and sugarcane molasses were tested as substrates for production of biomass and phycobiliproteins by Nostoc sp., varying their concentrations in relation to a mineral medium, BG11. All substrates increased the biomass and phycobiliproteins when compared with the control. Sugarcane molasses showed to be thebest substrate for production of both biomass and phycobiliproteins. Greater biomass production occurred in sugarcane molasses 1.0 g L-1 and it was 5.7 times greater than the control. With glucose, it was in 2.5 g L-1 and sucrose, in 1.5 g L-1, reaching 2.5 and 4.8 timesgreater than the control, respectively. For phycobiliproteins, the major production was in sugarcane molasses 1.0 g L-1, 12.5 times greater than the control. With glucose, it was in 1.0 g L-1 and sucrose, in 0,5 g L-1, reaching 3.0 and 4.5 times greater than the control, respectively. The Nostoc sp. assayed can grow mixotrophically, using glucose, sucrose, and sugarcane molasses as organic substrates, and a greater production of biomass andphycobiliproteins can be reached when compared with the autotrophic growth.Todos os substratos aumentaram a biomassa e ficobiliproteinas emrelação ao controle, meio mineral BG11. Melaço de cana-de-açúcar foi o melhor substrato tanto para a produção de biomassa como de ficobiliproteinas. A maior produção de biomassa ocorreu usando melaço de cana-de-açúcar 1,0 g L-1 sendo 5,7 vezes maior que o controle. Com glucose foi em 2,5 g L-1 e sacarose 1,5 g L-1, sendo 2,5 e 4,8 vezes maior que o controle, respectivamente. A maior produção de ficobiliproteinas ocorreu usando melaço de cana-de-açúcar 1,0 g L-1 sendo 12,5 vezes maior que o controle. Com glucose foi em 1,0g L-1 e sacarose 0,5 g L-1, 3,0 e 4,5 vezes maior que o controle, respectivamente. Nostoc sp. testado pode crescer mixotroficamente, usando glucose, sacarose e melaço de cana-deaçúcar como substratos orgânicos, uma maior produção de biomassa e

Device for correction of the spot dimensions and its form in the measuring CRT of the MELAS automatic unit

International Nuclear Information System (INIS)

Kachnova, O.A.; Kryutchenko, E.V.; Utochkin, B.A.; Fedotov, V.S.

1979-01-01

A digital-to-analog converter is described, designed for dynamic correction of beam focusing of the measuring cathode-ray tube (CRT) of the MELAS automatic device. The described converter consists of two identical units. Every unit generates a voltage proportional to square of deviations along the X and Y axes. Output voltages of both channels are summarized by an analog adder, transformed into current and are fed to the focusing system. The computer circuit used to correct the dimensions of the CRT beam uses microcircuits with low and medium levels of integration and has the following characteristics: the maximum correcting current is 12.4 mA, the direct component of the focusing current is 0.24 A, the correcting current instability is 0.08% and the reduced temperature instability of the total focusing current is 0.004%. The employment of the converter to correct the dimension and shape of the CRT spot makes it possible to reduce the spot diameter to 18 μm at the center of the face and 22 μm at the edges of the face operating field

Lactic acid production by L. curvatus in sugarcane molasses/ Produção de ácido lático por Lactobacillus curvatus em melaço de cana-de-açúcar

Directory of Open Access Journals (Sweden)

Antonio Sérgio de Oliveira

2003-05-01

Full Text Available Lactic acid is important due to its various applications. The bulk of world lactic acid production is used by the food industry and the rest is used in pharmaceutical, textile, leather, cosmetic and chemical industries. In this work, a 33 incomplete factorial design of the response-surface methodology was used to determine the best concentration of sugarcane molasses, yeast extract and peptone in the culture medium for the development of batch lactic fermentation by Lactobacillus curvatus. The fermentation was carried out at 37 ºC for 48 hours without agitation. The mathematical model given by the responsesurface methodology indicated a concentration of 10% (w/v of sugarcane molasses, 2% (w/v of yeast extract and 4% (w/v of peptone as the best conditions for the composition of culture medium for the lactic acid production by L. curvatus. Under these conditions, lactic acid production was 30,5 g/L, comparable with the result obtained in MRS medium, which produced 32,0g/L of lactic acid. Considering the low cost and high availability of the sugarcane molasses, it was concluded that it represented a good culture medium for lactic fermentation. Sugarcane molasses at 10% (w/v supplemented with yeast extract at 2% (w/v and peptone at 4% (w/v was used in the 3L batch lactic fermentation producing 37,5g/L of lactic acid.A maior parte da produção mundial de ácido lático é utilizada pela indústria de alimentos e o restante em indústrias farmacêutica, têxtil, de couro, cosmética e química. A Metodologia da Superfície de Resposta, planejamento fatorial incompleto 33, foi utilizada para estabelecer as melhores condições, relativas às concentrações, do meio de cultivo contendo melaço de cana-de-açúcar, extrato de levedura e peptona para desenvolvimento da fermentação descontínua por Lactobacillus curvatus. A fermentação se desenvolveu durante 48 horas sob temperatura de 37 ºC. O modelo matemático fornecido pela Metodologia da

Comparative Chromosome Map and Heterochromatin Features of the Gray Whale Karyotype (Cetacea).

Science.gov (United States)

Kulemzina, Anastasia I; Proskuryakova, Anastasia A; Beklemisheva, Violetta R; Lemskaya, Natalia A; Perelman, Polina L; Graphodatsky, Alexander S

2016-01-01

Cetacean karyotypes possess exceptionally stable diploid numbers and highly conserved chromosomes. To date, only toothed whales (Odontoceti) have been analyzed by comparative chromosome painting. Here, we studied the karyotype of a representative of baleen whales, the gray whale (Eschrichtius robustus, Mysticeti), by Zoo-FISH with dromedary camel and human chromosome-specific probes. We confirmed a high degree of karyotype conservation and found an identical order of syntenic segments in both branches of cetaceans. Yet, whale chromosomes harbor variable heterochromatic regions constituting up to a third of the genome due to the presence of several types of repeats. To investigate the cause of this variability, several classes of repeated DNA sequences were mapped onto chromosomes of whale species from both Mysticeti and Odontoceti. We uncovered extensive intrapopulation variability in the size of heterochromatic blocks present in homologous chromosomes among 3 individuals of the gray whale by 2-step differential chromosome staining. We show that some of the heteromorphisms observed in the gray whale karyotype are due to distinct amplification of a complex of common cetacean repeat and heavy satellite repeat on homologous autosomes. Furthermore, we demonstrate localization of the telomeric repeat in the heterochromatin of both gray and pilot whale (Globicephala melas, Odontoceti). Heterochromatic blocks in the pilot whale represent a composite of telomeric and common repeats, while heavy satellite repeat is lacking in the toothed whale consistent with previous studies. © 2016 S. Karger AG, Basel.

Investigating the potential use of environmental DNA (eDNA for genetic monitoring of marine mammals.

Directory of Open Access Journals (Sweden)

Andrew D Foote

Full Text Available The exploitation of non-invasive samples has been widely used in genetic monitoring of terrestrial species. In aquatic ecosystems, non-invasive samples such as feces, shed hair or skin, are less accessible. However, the use of environmental DNA (eDNA has recently been shown to be an effective tool for genetic monitoring of species presence in freshwater ecosystems. Detecting species in the marine environment using eDNA potentially offers a greater challenge due to the greater dilution, amount of mixing and salinity compared with most freshwater ecosystems. To determine the potential use of eDNA for genetic monitoring we used specific primers that amplify short mitochondrial DNA sequences to detect the presence of a marine mammal, the harbor porpoise, Phocoena phocoena, in a controlled environment and in natural marine locations. The reliability of the genetic detections was investigated by comparing with detections of harbor porpoise echolocation clicks by static acoustic monitoring devices. While we were able to consistently genetically detect the target species under controlled conditions, the results from natural locations were less consistent and detection by eDNA was less successful than acoustic detections. However, at one site we detected long-finned pilot whale, Globicephala melas, a species rarely sighted in the Baltic. Therefore, with optimization aimed towards processing larger volumes of seawater this method has the potential to compliment current visual and acoustic methods of species detection of marine mammals.

Bioaccumulation and biomagnification of classical flame retardants, related halogenated natural compounds and alternative flame retardants in three delphinids from Southern European waters

International Nuclear Information System (INIS)

Barón, E.; Giménez, J.; Verborgh, P.; Gauffier, P.; De Stephanis, R.; Eljarrat, E.; 2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona (Spain))" data-affiliation=" (Institute of Environmental Assessment and Water Research Studies (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona (Spain))" >Barceló, D.

2015-01-01

Occurrence and behaviour of classical (PBDEs) and alternative (HNs, HBB, PBEB, DBDPE and HBCD) flame retardants, together with naturally produced MeO-PBDEs, were studied in short-beaked common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus) and long-finned pilot whale (Globicephala melas) in two sampling locations from Southern European waters. PBDEs, Dec 602, Dec 603, DP, α-HBCD and two MeO-PBDEs were detected in all three species. ∑PBDEs were between 17 and 2680 ng/g lw; ∑HNs were between 1.1 and 59 ng/g lw; α-HBCD levels ranged between 3.2 and 641 ng/g lw; ∑MeO-PBDEs were between 34 and 1966 ng/g lw. Bottlenose dolphins were the most contaminated species and some individuals could present health risk for endocrine disruption since levels found were above the reported threshold (1500 ng/g lw). Stable isotope analysis was used to evaluate the biomagnification capacity of these compounds. PBDEs, MeO-PBDEs and Dec 602 showed a significant positive correlation with trophic position. - Highlights: • Several FRs were detected in three dolphin species from Southern European waters. • Concentrations of classical FRs were higher than concentrations of alternative FRs. • MeO-PBDE concentrations were generally similar to PBDE concentrations. • Evidence of biomagnification capacity of some FRs was observed. • Some individuals were above the threshold level associated to endocrine disruption. - Bioaccumulation and biomagnification of halogenated compounds in dolphins

Distribution and feeding ecology of dolphins along the Mid-Atlantic Ridge between Iceland and the Azores

Science.gov (United States)

Doksæter, L.; Olsen, E.; Nøttestad, L.; Fernö, A.

2008-01-01

During Leg 1 of the MAR-ECO expedition on the R.V. G.O. Sars in June 2004 four main species of dolphins were observed along the Mid-Atlantic Ridge from Iceland to the Azores: pilot whale ( Globicephala melas) ( n=326), short-beaked common dolphin ( Delphinus delphis) ( n=273), white-sided dolphin ( Lagenorhynchus acutus) ( n=103), and striped dolphin ( Stenella coeruleoalba) ( n=86). Pilot whales and white-sided dolphins were found in cold (5-16 °C) and less-saline (34.6-35.8‰) water masses in the northern part of the study area, whereas common and striped dolphins inhabited warmer (12-22 °C) and more-saline (34.8-36.7‰) waters in the south. Dolphins tended to aggregate in areas of steep slopes, but actual bottom depth appeared to be less important. Based on spatial correlations between dolphin occurrence and candidate prey organisms recorded acoustically and by midwater trawling, mesopelagic fishes and squids were assumed to be important prey items, with Benthosema glaciale probably being the most important prey for pilot whales and white-sided dolphins, while Lampanyctus macdonaldi, Stomias boa ferox and Chauliodus sloani were probably of particular importance for common dolphins. Cephalopods, especially Gonatus sp. and Teuthowenia megalops were the most likely prey species of pilot whales and striped dolphins, respectively. The difference in physical habitat north and south of the Sub-polar Frontal Zone seemed to have important effects on prey distribution, in turn influencing dolphin distribution.

75 FR 36102 - General and Plastic Surgery Devices Panel of the Medical Devices Advisory Committee; Notice of...

Science.gov (United States)

2010-06-24

... will discuss, make recommendations, and vote on premarket approval application for MelaFind, sponsored by MELA Sciences, Inc. MelaFind is a non-invasive computer vision system intended to assist in the... characteristics of melanoma, before a final decision to biopsy has been rendered. MelaFind acquires and displays...

Produção de L-asparaginase por Zymomonas mobilis durante a fermentação do melaço: otimização das condições de cultivo utilizando delineamento fatorial - DOI: 10.4025/actascitechnol.v28i2.1178

Directory of Open Access Journals (Sweden)

Doumit Camilios Neto

2006-03-01

Full Text Available A L-asparaginase é uma enzima com atividade anti-leucêmica produzida por microrganismos, principalmente bactérias gram-negativas. Zymomonas mobilis é uma bactéria gram-negativa, que apresenta potencial para produção de L-asparaginase. Esse estudo buscou a otimização da produção de L-asparaginase por Zymomonas mobilis, durante a fermentação do melaço de cana-de-açúcar, utilizando um delineamento fatorial incompleto 33. O modelo obtido através da metodologia de superfície de resposta foi otimizado pelo software Otplex. Obteve-se bom ajuste do modelo aos dados experimentais, sendo o coeficiente de determinação total (R2, 95%. A máxima atividade enzimática (16,55 UI L-1 foi obtida com uma concentração de açúcares redutores totais no melaço de 100,0 g L-1, 2,0 g L-1 de extrato de levedura e com 21 horas de fermentação. A validação experimental confirmou a capacidade preditiva do modelo, sendo a diferença entre resposta estimada(Ŷ1 e resposta observada (Y1 apenas de 1%.

Technology-enabled examinations of cardiac rhythm, optic nerve, oral health, tympanic membrane, gait and coordination evaluated jointly with routine health screenings: an observational study at the 2015 Kumbh Mela in India

Science.gov (United States)

Gupta, Otkrist; Patalano II, Vincent; Mohit, Mrinal; Merchant, Rikin; Subramanian, S V

2018-01-01

Objectives Technology-enabled non-invasive diagnostic screening (TES) using smartphones and other point-of-care medical devices was evaluated in conjunction with conventional routine health screenings for the primary care screening of patients. Design Dental conditions, cardiac ECG arrhythmias, tympanic membrane disorders, blood oxygenation levels, optic nerve disorders and neurological fitness were evaluated using FDA-approved advanced smartphone powered technologies. Routine health screenings were also conducted. A novel remote web platform was developed to allow expert physicians to examine TES data and compare efficacy with routine health screenings. Setting The study was conducted at a primary care centre during the 2015 Kumbh Mela in Maharashtra, India. Participants 494 consenting 18–90 years old adults attending the 2015 Kumbh Mela were tested. Results TES and routine health screenings identified unique clinical conditions in distinct patients. Intraoral fluorescent imaging classified 63.3% of the population with dental caries and periodontal diseases. An association between poor oral health and cardiovascular illnesses was also identified. Tympanic membrane imaging detected eardrum abnormalities in 13.0% of the population, several with a medical history of hearing difficulties. Gait and coordination issues were discovered in eight subjects and one subject had arrhythmia. Cross-correlations were observed between low oxygen saturation and low body mass index (BMI) with smokers (p=0.0087 and p=0.0122, respectively), and high BMI was associated with elevated blood pressure in middle-aged subjects. Conclusions TES synergistically identified clinically significant abnormalities in several subjects who otherwise presented as normal in routine health screenings. Physicians validated TES findings and used routine health screening data and medical history responses for comprehensive diagnoses for at-risk patients. TES identified high prevalence of oral diseases

Crescimento mixotrófico de Nostoc sp. Glucose, sacarose e melaço de cana-de-açúcar foram testados como substratos para produção de biomassa e ficobiliproteinas - DOI: 10.4025/actascibiolsci.v29i1.121 Mixotrophic growth of Nostoc sp. on glucose, sucrose and sugarcane molasses for phycobiliprotein production

Directory of Open Access Journals (Sweden)

Maria Helena Pimenta Pinotti

2007-11-01

Full Text Available Todos os substratos aumentaram a biomassa e ficobiliproteinas em relação ao controle, meio mineral BG11. Melaço de cana-de-açúcar foi o melhor substrato tanto para a produção de biomassa como de ficobiliproteinas. A maior produção de biomassa ocorreu usando melaço de cana-de-açúcar 1,0 g L-1 sendo 5,7 vezes maior que o controle. Com glucose foi em 2,5 g L-1 e sacarose 1,5 g L-1, sendo 2,5 e 4,8 vezes maior que o controle, respectivamente. A maior produção de ficobiliproteinas ocorreu usando melaço de cana-de-açúcar 1,0 g L-1 sendo 12,5 vezes maior que o controle. Com glucose foi em 1,0 g L-1 e sacarose 0,5 g L-1, 3,0 e 4,5 vezes maior que o controle, respectivamente. Nostoc sp. testado pode crescer mixotroficamente, usando glucose, sacarose e melaço de cana-deaçúcar como substratos orgânicos, uma maior produção de biomassa e ficobiliproteinas podendo ser alcançada nessas condições quando comparadas com o crescimento autotrófico.Glucose, sacarose, and sugarcane molasses were tested as substrates for production of biomass and phycobiliproteins by Nostoc sp., varying their concentrations in relation to a mineral medium, BG11. All substrates increased the biomass and phycobiliproteins when compared with the control. Sugarcane molasses showed to be the best substrate for production of both biomass and phycobiliproteins. Greater biomass production occurred in sugarcane molasses 1.0 g L-1 and it was 5.7 times greater than the control. With glucose, it was in 2.5 g L-1 and sucrose, in 1.5 g L-1, reaching 2.5 and 4.8 times greater than the control, respectively. For phycobiliproteins, the major production was in sugarcane molasses 1.0 g L-1, 12.5 times greater than the control. With glucose, it was in 1.0 g L-1 and sucrose, in 0,5 g L-1, reaching 3.0 and 4.5 times greater than the control, respectively. The Nostoc sp. assayed can grow mixotrophically, using glucose, sucrose, and sugarcane molasses as organic substrates, and a

Assessing Disease and Mortality among Small Cetaceans Stranded at a World Heritage Site in Southern Brazil.

Directory of Open Access Journals (Sweden)

Isabela G Domiciano

Full Text Available Cetaceans are considered environmental sentinels and their health often reflects either anthropogenic or natural spatio-temporal disturbances. This study investigated the pathological findings and mortality of small cetaceans with the aim of detecting hazards and monitoring health trends in a high-biodiversity area. Between 2007 and 2012, 218 stranded cetaceans were recorded on the Paraná coast, southern Brazil. Fifty-seven (26.1% of these animals, including 50 Sotalia guianensis, 2 Pontoporia blainvillei, 2 Stenella frontalis, 1 Stenella longirostris, 1 Tursiops truncatus and 1 Globicephala melas were necropsied and samples were collected for histopathology. Causes of death were determined in 46 of the 57 (80.7% animals and most (30 or 65.2% were ascribed to anthropogenic activities, including fisheries bycatch (28/30 and trauma (2/30. The remaining 16 fatalities were considered natural, and attributed to pneumonia (10/16, emaciation (3/16, septicemia (1/16, neonatal pathology (1/16 and choking via food obstruction (1/16. Irrespective of the cause, bronchointerstitial pneumonia, associated with parasitism, lymphadenitis and membranous glomerulonephritis were common findings among all fatalities. These results suggest, that while anthropogenic activities are a leading cause of cetacean strandings in Paraná, underlying pre-existing diseases may contribute towards deaths. Although the studied area is considered a biosphere reserve by UNESCO, complex anthropogenic and natural interactions might be occurring, increasing cetacean susceptibility to hazards. This study may help facilitate developing an effective conservation plan for coastal cetaceans focusing on reducing fisheries interactions, habitat degradation and pollution as mechanisms for ultimately increasing species resilience.

Polychlorinated naphthalenes (PCNs) in sub-Arctic and Arctic marine mammals, 1986–2009

International Nuclear Information System (INIS)

Rotander, Anna; Bavel, Bert van; Rigét, Frank; Auðunsson, Guðjón Atli; Polder, Anuschka; Gabrielsen, Geir Wing; Víkingsson, Gísli; Mikkelsen, Bjarni; Dam, Maria

2012-01-01

A selection of PCN congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbour porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986–2009). A large geographical area of the North Atlantic and Arctic areas was covered. PCN congeners 48, 52, 53, 66 and 69 were found in the blubber samples between 0.03 and 5.9 ng/g lw. Also PCBs were analyzed in minke whales and fin whales from Iceland and the total PCN content accounted for 0.2% or less of the total non-planar PCB content. No statistically significant trend in contaminant levels could be established for the studied areas. However, in all species except minke whales caught off Norway the lowest ∑PCN concentrations were found in samples from the latest sampling period. - Highlights: ► PCN concentrations are described in a wide variety of marine mammal species. ► A large geographical area of the North Atlantic and Arctic areas is covered. ► Pooled blubber samples covering a time period of 23 years are evaluated. ► Species- and geographic-dependent PCN congener distribution is seen. ► A decrease in the PCN load is indicated in the studied areas in recent years. - Analysis of PCNs in seven marine mammal species sampled over a 23 year period indicates a decline in the PCN load in sub-Arctic and Arctic areas in recent years.

Progress in Diagnosing Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like Episodes

Directory of Open Access Journals (Sweden)

Ying-Xin Wang

2015-01-01

Conclusions: MELAS involves multiple systems with variable clinical symptoms and recurrent episodes. The prognosis of MELAS patients depends on timely diagnosis. Therefore, overall diagnosis of MELAS should be based on the maternal inheritance family history, clinical manifestation, and findings from serial MRI, muscle biopsy, and genetics.

NCBI nr-aa BLAST: CBRC-DSIM-02-0026 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-02-0026 gb|AAG22709.1|AF280553_1 methuselah [Drosophila melanogaster] gb|...AAG22710.1|AF280554_1 methuselah [Drosophila melanogaster] gb|AAG22711.1|AF280555_1 methuselah [Drosophila mela...nogaster] gb|AAG22713.1|AF280557_1 methuselah [Drosophila melanogaster] gb|AAG22714.1|AF280558_1 methuselah [Drosophila mela...nogaster] gb|AAG22716.1|AF280560_1 methuselah [Drosophila mela...nogaster] gb|AAG22718.1|AF280562_1 methuselah [Drosophila melanogaster] gb|AAG22720.1|AF280564_1 methuselah [Drosophila mela

NCBI nr-aa BLAST: CBRC-DYAK-06-0016 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DYAK-06-0016 ref|NP_572183.1| CG6986-PA, isoform A [Drosophila melanogaster] r...ef|NP_726950.1| CG6986-PB, isoform B [Drosophila melanogaster] ref|NP_001014723.1| CG6986-PD, isoform D [Drosophila mela...nogaster] ref|NP_001014724.1| CG6986-PC, isoform C [Drosophila melanogaster] gb|AAM75074.1| RE56254p [Drosophila mela...nogaster] gb|AAF45980.2| CG6986-PA, isoform A [Drosophila mela...nogaster] gb|AAN09130.1| CG6986-PB, isoform B [Drosophila melanogaster] gb|AAX52477.1| CG6986-PC, isoform C [Drosophila mela

NCBI nr-aa BLAST: CBRC-DSIM-08-0021 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-08-0021 ref|NP_572183.1| CG6986-PA, isoform A [Drosophila melanogaster] r...ef|NP_726950.1| CG6986-PB, isoform B [Drosophila melanogaster] ref|NP_001014723.1| CG6986-PD, isoform D [Drosophila mela...nogaster] ref|NP_001014724.1| CG6986-PC, isoform C [Drosophila melanogaster] gb|AAM75074.1| RE56254p [Drosophila mela...nogaster] gb|AAF45980.2| CG6986-PA, isoform A [Drosophila mela...nogaster] gb|AAN09130.1| CG6986-PB, isoform B [Drosophila melanogaster] gb|AAX52477.1| CG6986-PC, isoform C [Drosophila mela

NCBI nr-aa BLAST: CBRC-DYAK-02-0049 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DYAK-02-0049 gb|AAS74383.1| 5-HT1B [Drosophila melanogaster] gb|AAS74385.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74397.1| 5-HT1B [Drosophila melanogaster] gb|AAS74398.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74401.1| 5-HT1B [Drosophila melanogaster] gb|AAS74414.1| 5-HT1B [Drosophila melanog...aster] gb|AAS74416.1| 5-HT1B [Drosophila melanogaster] gb|AAS74418.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74419.1| 5-HT1B [Drosophila melanogaster] gb|AAS74424.1| 5-HT1B [Drosophila mela

NCBI nr-aa BLAST: CBRC-DMEL-02-0053 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DMEL-02-0053 gb|AAS74380.1| 5-HT1B [Drosophila melanogaster] gb|AAS74382.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74389.1| 5-HT1B [Drosophila melanogaster] gb|AAS74402.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74403.1| 5-HT1B [Drosophila melanogaster] gb|AAS74405.1| 5-HT1B [Drosophila melanog...aster] gb|AAS74406.1| 5-HT1B [Drosophila melanogaster] gb|AAS74411.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74412.1| 5-HT1B [Drosophila melanogaster] gb|AAS74413.1| 5-HT1B [Drosophila mela

NCBI nr-aa BLAST: CBRC-DYAK-02-0049 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DYAK-02-0049 gb|AAS74384.1| 5-HT1B [Drosophila melanogaster] gb|AAS74386.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74388.1| 5-HT1B [Drosophila melanogaster] gb|AAS74390.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74392.1| 5-HT1B [Drosophila melanogaster] gb|AAS74394.1| 5-HT1B [Drosophila melanog...aster] gb|AAS74395.1| 5-HT1B [Drosophila melanogaster] gb|AAS74396.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74404.1| 5-HT1B [Drosophila melanogaster] gb|AAS74408.1| 5-HT1B [Drosophila mela

NCBI nr-aa BLAST: CBRC-DMEL-02-0053 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DMEL-02-0053 gb|AAS74384.1| 5-HT1B [Drosophila melanogaster] gb|AAS74386.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74388.1| 5-HT1B [Drosophila melanogaster] gb|AAS74390.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74392.1| 5-HT1B [Drosophila melanogaster] gb|AAS74394.1| 5-HT1B [Drosophila melanog...aster] gb|AAS74395.1| 5-HT1B [Drosophila melanogaster] gb|AAS74396.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74404.1| 5-HT1B [Drosophila melanogaster] gb|AAS74408.1| 5-HT1B [Drosophila mela

NCBI nr-aa BLAST: CBRC-DSIM-02-0056 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-02-0056 gb|AAS74384.1| 5-HT1B [Drosophila melanogaster] gb|AAS74386.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74388.1| 5-HT1B [Drosophila melanogaster] gb|AAS74390.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74392.1| 5-HT1B [Drosophila melanogaster] gb|AAS74394.1| 5-HT1B [Drosophila melanog...aster] gb|AAS74395.1| 5-HT1B [Drosophila melanogaster] gb|AAS74396.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74404.1| 5-HT1B [Drosophila melanogaster] gb|AAS74408.1| 5-HT1B [Drosophila mela

NCBI nr-aa BLAST: CBRC-DSIM-02-0057 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-02-0057 gb|AAS74185.1| 5-HT1A [Drosophila melanogaster] gb|AAS74209.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74210.1| 5-HT1A [Drosophila melanogaster] gb|AAS74211.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74224.1| 5-HT1A [Drosophila melanogaster] gb|AAS74234.1| 5-HT1A [Drosophila melanog...aster] gb|AAS74254.1| 5-HT1A [Drosophila melanogaster] gb|AAS74258.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74262.1| 5-HT1A [Drosophila melanogaster] gb|AAS74278.1| 5-HT1A [Drosophila mela

NCBI nr-aa BLAST: CBRC-DSIM-02-0056 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-02-0056 gb|AAS74383.1| 5-HT1B [Drosophila melanogaster] gb|AAS74385.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74397.1| 5-HT1B [Drosophila melanogaster] gb|AAS74398.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74401.1| 5-HT1B [Drosophila melanogaster] gb|AAS74414.1| 5-HT1B [Drosophila melanog...aster] gb|AAS74416.1| 5-HT1B [Drosophila melanogaster] gb|AAS74418.1| 5-HT1B [Drosophila mela...nogaster] gb|AAS74419.1| 5-HT1B [Drosophila melanogaster] gb|AAS74424.1| 5-HT1B [Drosophila mela

Conhecimento de puérperas acerca do método anticoncepcional da lactação com amenorreia

Directory of Open Access Journals (Sweden)

Jamile Lopes de Moraes Moraes

2015-01-01

Full Text Available Objetivo: verificar el nivel de conocimiento de puérperas acerca del método de amenorrea de la lactancia (MELA como recurso anticonceptivo. Materiales y método: investigación transversal realizada con 278 puérperas internadas en una maternidad de referencia de Fortaleza (Ceará, noreste de Brasil, de febrero a mayo del 2012. Resultados: se encontró que 131 (47,1 % habían oído sobre el MELA y, de ellas, 58 (44,3 % declararon conocerlo antes del embarazo y 56 (42,7 % en el prenatal; 94 (71,6 % puérperas no creen en su eficacia y 100 (76,3 % desconocían los criterios para uso seguro. La fuente de informaciones acerca del método para 43 (32,8 % puérperas fue amigos, familiares o conocidos, es decir, de modo informal, y 71 (54,1 % no recibieron orientación de profesionales de la salud. Conclusiones: vacíos en el conocimiento de puérperas generan bajo uso y uso incorrecto del MELA; igualmente se destaca el elevado porcentaje de puérperas sin orientación por parte de profesionales de la salud.

Taxonomy Icon Data: fruit fly [Taxonomy Icon

Lifescience Database Archive (English)

Full Text Available fruit fly Drosophila melanogaster Arthropoda Drosophila_melanogaster_L.png Drosophila_mela...nogaster_NL.png Drosophila_melanogaster_S.png Drosophila_melanogaster_NS.png http://biosciencedbc.jp/...taxonomy_icon/icon.cgi?i=Drosophila+melanogaster&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Drosophila+mela...nogaster&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Drosophila+mela...nogaster&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Drosophila+melanogaster&t=NS ...

Differentiation of Neonatal Human-Induced Pluripotent Stem Cells to Prostate Epithelial Cells: A Model to Study Prostate Cancer Development

Science.gov (United States)

2013-06-01

38, 40, 41]. Because these “ mela - noma stem cells” (MSC) are sometimes so numerous, some have argued that the CSC model may not apply to melanoma...40]. There are data from two groups indicating that mela - noma lesions contain a CSC subset character- ized by CD271 expression [25, 26]. In a...neuronal proteins and neuron- like differentiation has been long recognized in neoplastic melanocytes [46, 47]. Certain mela - noma cell lines that

The Cetaceans of Ghana, a Validated Faunal Checklist | Van ...

African Journals Online (AJOL)

... S. longirostris longirostris*, S. attenuata, S. frontalis, Delphinus capensis capensis*, Lagenodelphis hosei, Steno bredanensis, Grampus griseus, Peponocephala electra*, Feresa attenuata**, Globicephala macrorhynchus, Orcinus orca*, Pseudorca crassidens*, Kogia sima**, Physetermacrocephalus*, Ziphius cavirostris** ...

Polybrominated diphenyl ethers (PBDEs) in marine mammals from Arctic and North Atlantic regions, 1986-2009.

Science.gov (United States)

Rotander, Anna; van Bavel, Bert; Polder, Anuschka; Rigét, Frank; Auðunsson, Guðjón Atli; Gabrielsen, Geir Wing; Víkingsson, Gísli; Bloch, Dorete; Dam, Maria

2012-04-01

A selection of PBDE congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbor porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986-2009). The analytes were extracted and cleaned-up using open column extraction and multi-layer silica gel column chromatography, and the analysis was performed on a GC-MS system operating in the NCI mode. The highest PBDE levels were found in the toothed whale species pilot whale and white-sided dolphin, and the lowest levels in fin whales and ringed seals. One-sided analyses of variance (ANOVA) followed by Tukey comparisons of means were applied to test for differences between years and sampling areas. Due to inter-year sampling variability, only general comparisons of PBDE concentrations between different sampling areas could be made. Differences in PBDE concentrations between three sampling periods, from 1986 to 2007, were evaluated in samples of pilot whales, ringed seals, white-sided dolphins and hooded seals. The highest PBDE levels were found in samples from the late 1990s or beginning of 2000, possibly reflecting the increase in the global production of technical PBDE mixtures in the 1990s. The levels of BDE #153 and #154 increased relative to the total PBDE concentration in some of the species in recent years, which may indicate an increased relative exposure to higher brominated congeners. In order to assess the effect of measures taken in legally binding international agreements, it is important to continuously monitor POPs such as PBDEs in sub-Arctic and Arctic environments. Copyright © 2011 Elsevier Ltd. All rights reserved.

Distribution and abundance of fin whales (Balaenoptera physalus in the Northeast and Central Atlantic as inferred from the North Atlantic Sightings Surveys 1987-2001

Directory of Open Access Journals (Sweden)

Gísli A Víkingsson

2013-10-01

Full Text Available North Atlantic Sightings Surveys (NASS is a series of large scale international cetacean line transect surveys, conducted in 1987, 1989, 1995 and 2001, that covered a large part of the central and eastern North Atlantic. Target species were fin (Balaenoptera physalus, common minke (B. acutorostrata, pilot (Globicephala melas and sei (B. borealis whales. Here we present new estimates of abundance for fin whales from the 2 most recent surveys and analysis of trends throughout the survey period. Fin whales were found in highest densities in the Irminger Sea between Iceland and Greenland. Abundance of fin whales in the survey area of the Icelandic and Faroese vessels (Central North Atlantic was estimated as 19,672 (95% C.I. 12,083-28,986 animals in 1995 and 24,887 (95% C.I. 18,186-30,214 in 2001. The estimates are negatively biased because of whales diving during the passage of vessels, and whales being missed by observers, but these and other potential biases are likely small for this species. The abundance of fin whales increased significantly over the survey period. For all areas combined the estimated annual growth rate was 4%. An estimated annual increase of 10% in the area between Iceland and Greenland was responsible for most of this overall increase in numbers of fin whales in the area. Although high, the estimated rates of increase are not out of bounds of biological plausibility and can thus be viewed as recovery of a depleted population. However, the apparent pattern of population growth and the whaling history in the area indicate that fin whales made a significant recovery during the first half of the 20th century and that the recent observed high growth rates cannot be explained solely by recovery after overexploitation.

NCBI nr-aa BLAST: CBRC-DMEL-02-0081 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DMEL-02-0081 ref|NP_611813.1| CG4019-PA, isoform A [Drosophila melanogaster] r...ef|NP_726348.1| CG4019-PB, isoform B [Drosophila melanogaster] ref|NP_726349.1| CG4019-PD, isoform D [Drosophila mela...nogaster] gb|AAF47036.1| CG4019-PD, isoform D [Drosophila melanogaster] gb|AAM68261.1| CG4019-PA, isoform A [Drosophila mela...nogaster] gb|AAM68262.1| CG4019-PB, isoform B [Drosophila mela...nogaster] gb|AAQ23523.1| RH68439p [Drosophila melanogaster] NP_611813.1 2e-45 50% ...

Enlightenment and School History in 19th Century Greece: the Case of Gerostathis by Leon Melas (1862-1901

Directory of Open Access Journals (Sweden)

Harris Athanasiades

2017-01-01

Full Text Available Students in present-day Greek schools are taught History as a biography of the Greek nation from the Mycenaean times to the present. Over the course of three millennia, the Greek nation has experienced three periods of cultural flourishing and political autonomy: (i the period of Antiquity (from the times of legendary King Agamemnon to those of Alexander the Great, (ii the Byzantine period (from Justinian’s ascension in the 6th century to the Fall of Constantinople in 1453, and (iii the modern era (from the War of Independence in 1821 to the present day. However, in this article we argue that in the 19th century the history taught in Greek schools differed substantially from the tripartite schema described above. In support of our thesis, we examine the most popular school textbook of the 19th century, O Gerostathis, by Leon Melas. In the Gerostathis, the history of the Greek nation is identified with that of Classical Greece (i.e. from the 6th century BC to the 4th century BC, which is held up as an exemplary era worthy of emulation. In contrast, the rise of Macedon under Philip II signals the cultural decline of the Greeks and the loss of their political autonomy, which was not regained for two millennia, until the 1821 national revolution. In that period, the Greek nation ceased not to exist, but survived as a subjugate of the Macedonians, the Romans, and finally the Ottomans. The Byzantine, on the other hand, is described as an unremarkable period of decadence that is only worth mentioning in relation to its final period, that of the Palaeologus dynasty, which bestowed upon the Greeks a legacy of resistance against the Ottomans. We argue that the above reading of the Greek past owed much to the Enlightenment, which as an intellectual movement still exerted a powerful influence (albeit to a gradually diminishing degree on Greek intellectuals up to the latter third of the 19th century.

Nitric oxide scavenging by hemoglobin or nitric oxide synthase inhibition by N-Nitro-L-arginine induces cortical spreading ischemia when K+0+ is increased in the subarachnoid space

DEFF Research Database (Denmark)

Dreier, J.P.; Körner, K.; Ebert, Nathalie

1998-01-01

Cerebral blood flow, nitric oxide, potassium, spreading depression, vasospasm, migraine, migrainous stroke, mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS)......Cerebral blood flow, nitric oxide, potassium, spreading depression, vasospasm, migraine, migrainous stroke, mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS)...

Governance of Cutaneous Photocarcinogenesis by Chronic UVA-Exposed Dermal Fibroblasts

Science.gov (United States)

2014-09-01

2b). In contrast, bystander mela - nocytes cocultured with unirradiated cells led to no appreci- able induction of DCF fluorescence. Experiments were...Life Technologies) containing human mela - nocyte growth supplement (5 ml in 500 ml of media; Life Technolo- gies) and 10% penicillin/streptomycin

In Vivo Clotting Breast Cancer Stem Cells and Platelets: A New Endogenous Precursor of Metastasis Progression

Science.gov (United States)

2013-05-01

In this scenario, PA (or PT) signals can be generated using intrinsic chromophores and pigments such as hemoglobin, mela - nin, cytochromes, or...medical inter- vention may provoke metastasis; however, no direct evidences were previously presented. Using label-free PAFC and the mela - noma-bearing

NCBI nr-aa BLAST: CBRC-DSIM-04-0001 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-04-0001 gb|AAS74960.1| 5-HT2 [Drosophila melanogaster] gb|AAS74962.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS74964.1| 5-HT2 [Drosophila melanogaster] gb|AAS74966.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS74970.1| 5-HT2 [Drosophila melanogaster] gb|AAS74972.1| 5-HT2 [Drosophila melanogaster]... gb|AAS74976.1| 5-HT2 [Drosophila melanogaster] gb|AAS74978.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS74979.1| 5-HT2 [Drosophila melanogaster] gb|AAS74980.1| 5-HT2 [Drosophila melanogaster

NCBI nr-aa BLAST: CBRC-DSIM-04-0001 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-04-0001 gb|AAS74999.1| 5-HT2 [Drosophila melanogaster] gb|AAS75013.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS75024.1| 5-HT2 [Drosophila melanogaster] gb|AAS75026.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS75043.1| 5-HT2 [Drosophila melanogaster] gb|AAS75052.1| 5-HT2 [Drosophila melanogaster]... gb|AAS75056.1| 5-HT2 [Drosophila melanogaster] gb|AAS75073.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS75095.1| 5-HT2 [Drosophila melanogaster] AAS74999.1 1e-156 96% ...

NCBI nr-aa BLAST: CBRC-DMEL-04-0001 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DMEL-04-0001 gb|AAS74999.1| 5-HT2 [Drosophila melanogaster] gb|AAS75013.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS75024.1| 5-HT2 [Drosophila melanogaster] gb|AAS75026.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS75043.1| 5-HT2 [Drosophila melanogaster] gb|AAS75052.1| 5-HT2 [Drosophila melanogaster]... gb|AAS75056.1| 5-HT2 [Drosophila melanogaster] gb|AAS75073.1| 5-HT2 [Drosophila mela...nogaster] gb|AAS75095.1| 5-HT2 [Drosophila melanogaster] AAS74999.1 1e-165 100% ...

Evaluation of DNA Repair Function as a Predictor of Response in a Clinical Trial of PARP Inhibitor Monotherapy for Recurrent Ovarian Carcinoma

Science.gov (United States)

2015-10-01

tumors that occur in families with germline BRCA1/2 mutations, including pancreatic cancer, mela - noma, and prostate cancer, have also been reported.20...temozolomide in mela - noma, BC, glioblastoma, and acute leukemia, as well as with signal transduction inhibitors (eg, gefitinib in EGFR-mutant non–small

Melanoma Incidence Rates in Active Duty Military Personnel Compared With a Population-Based Registry in the United States, 2000-2007

Science.gov (United States)

2014-03-01

to include two or more itipatient and outpatient prirnary diagnosis and kept other aspects of the algorithm the same, and found the overall mela - noma...17 population. Military service members are represented by a range of race and ethnic combinations, with a spectrum of skin mela - nin content. The

Artiss Symposium 2013: Psychiatry and Sleep Disorders

Science.gov (United States)

2013-06-05

times when their endog- enous levels of melatonin were low, high or normal. When you give mela - tonin exogenously in periods when endogenous levels...not allow them to retreat to darkness or dim light following the bright light pulse. Then, very specifically, you would give mela - tonin, 0.5

The Mela Study: exploring barriers to diabetes research in black and minority ethnic groups.

Science.gov (United States)

Hood, Gillian A; Chowdhury, Tahseen A; Griffiths, Christopher J; Hood, Rosie K E; Mathews, Christopher; Hitman, Graham A

2015-01-01

Black and minority ethnic (BME) groups are particularly susceptible to diabetes and its vascular complications in the United Kingdom and most western societies. To understand potential predisposition and tailor treatments accordingly, there is a real need to engage these groups in diabetes research. Despite this, BME participation in research studies continues to remain low in most countries and this may be a contributory factor to reduced health outcomes and poorer quality of life in these groups. This study explores the barriers BME groups may have towards participation in diabetes research in one area of East London, and includes local recommendations on how to improve this for the future. A questionnaire designed from previously reported exploratory work and piloted in several BME localities was distributed at the East London Bangladeshi Mela and similar cultural and religious events in London, UK. People were asked opportunistically to complete the survey themselves if they understood English, or discuss their responses with an advocate. The purpose of the questionnaire was to understand current local awareness with regards to diabetes, identify specific BME barriers and attitudes towards diabetes research by ethnicity, gender and age, and gain insight into how these barriers may be addressed. Of 1682 people surveyed (16-90 years; median age 40 years), 36.4% were South Asian, 25.9% White, and 11.1% Black and other ethnicities; 26.6% withheld their ethnicity. Over half cited language problems generally (54%) and lack of research awareness (56%) as main barriers to engaging in research. South Asian groups were more likely to cite research as too time consuming (42%) whereas Black groups were more concerned with potential drug side effects in research (39%). Participants expressed a general mistrust of research, and the need for researchers to be honest in their approach. Recommendations for increased participation in South Asian groups centred round both helping

Trends in Nanosecond Melanosome Microcavitation Up to 1540 Nanometers

Science.gov (United States)

2015-09-01

these absorption coeffi- cients are probably due to the high water content and low mela - nin concentration in the RPE layer, as a simple first-order...comparison of radiant exposure thresholds of bovine mela - nosomes as a function of wavelength, on a log scale, from 532 to 1540 nm, at ambient

Histone Code Modulation by Oncogenic PWWP-Domain Protein in Breast Cancers

Science.gov (United States)

2014-08-01

the pathogenesis of a wide range of human cancers, including colon, lung, glioblastoma and mela - noma (Ostman et al., 2006; Solomon et al., 2008...Beroukhim R, Mermel CH, Loda M, Ait-Si-Ali S, Garraway LA, Young RA and Zon LI. The histone methyltrans- ferase SETDB1 is recurrently amplified in mela

Transient Delivery of Adenosine as a Novel Therapy to Prevent Epileptogenesis

Science.gov (United States)

2015-10-01

Chemother 6:98–101. Bukoski RD, Sparks HV, and Mela -Riker LM (1986) A role for mitochondria in myocardial adenosine production. Adv Exp Med Biol 194:157–167...Bukoski RD, Sparks HV, and Mela LM (1983) Rat heart mitochondria release adenosine. Biochem Biophys Res Commun 113:990–995. Burnstock G, Fredholm BB

A Wide Range of 3243A>G/tRNALeu(UUR) (MELAS) Mutation Loads May Segregate in Offspring through the Female Germline Bottleneck

Science.gov (United States)

Pallotti, Francesco; Binelli, Giorgio; Fabbri, Raffaella; Valentino, Maria L.; Vicenti, Rossella; Macciocca, Maria; Cevoli, Sabina; Baruzzi, Agostino; DiMauro, Salvatore; Carelli, Valerio

2014-01-01

Segregation of mutant mtDNA in human tissues and through the germline is debated, with no consensus about the nature and size of the bottleneck hypothesized to explain rapid generational shifts in mutant loads. We investigated two maternal lineages with an apparently different inheritance pattern of the same pathogenic mtDNA 3243A>G/tRNALeu(UUR) (MELAS) mutation. We collected blood cells, muscle biopsies, urinary epithelium and hair follicles from 20 individuals, as well as oocytes and an ovarian biopsy from one female mutation carrier, all belonging to the two maternal lineages to assess mutant mtDNA load, and calculated the theoretical germline bottleneck size (number of segregating units). We also evaluated “mother-to-offspring” segregations from the literature, for which heteroplasmy assessment was available in at least three siblings besides the proband. Our results showed that mutation load was prevalent in skeletal muscle and urinary epithelium, whereas in blood cells there was an inverse correlation with age, as previously reported. The histoenzymatic staining of the ovarian biopsy failed to show any cytochrome-c-oxidase defective oocyte. Analysis of four oocytes and one offspring from the same unaffected mother of the first family showed intermediate heteroplasmic mutant loads (10% to 75%), whereas very skewed loads of mutant mtDNA (0% or 81%) were detected in five offspring of another unaffected mother from the second family. Bottleneck size was 89 segregating units for the first mother and 84 for the second. This was remarkably close to 88, the number of “segregating units” in the “mother-to-offspring” segregations retrieved from literature. In conclusion, a wide range of mutant loads may be found in offspring tissues and oocytes, resulting from a similar theoretical bottleneck size. PMID:24805791

Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope

Science.gov (United States)

Di Tullio, Juliana Couto; Gandra, Tiago B. R.; Zerbini, Alexandre N.; Secchi, Eduardo R.

2016-01-01

Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m) and slope (1500m) off southeastern and southern Brazil (~23°S to ~34°S). The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the subtropical Southwestern

NCBI nr-aa BLAST: CBRC-DMEL-02-0054 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DMEL-02-0054 gb|AAS74186.1| 5-HT1A [Drosophila melanogaster] gb|AAS74187.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74231.1| 5-HT1A [Drosophila melanogaster] gb|AAS74233.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74373.1| 5-HT1A [Drosophila melanogaster] AAS74186.1 0.0 100% ...

NCBI nr-aa BLAST: CBRC-DYAK-02-0048 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DYAK-02-0048 gb|AAS74186.1| 5-HT1A [Drosophila melanogaster] gb|AAS74187.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74231.1| 5-HT1A [Drosophila melanogaster] gb|AAS74233.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74373.1| 5-HT1A [Drosophila melanogaster] AAS74186.1 1e-163 91% ...

NCBI nr-aa BLAST: CBRC-DSIM-02-0057 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-02-0057 gb|AAS74196.1| 5-HT1A [Drosophila melanogaster] gb|AAS74220.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74309.1| 5-HT1A [Drosophila melanogaster] gb|AAS74310.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74335.1| 5-HT1A [Drosophila melanogaster] AAS74196.1 1e-176 97% ...

NCBI nr-aa BLAST: CBRC-DSIM-02-0057 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DSIM-02-0057 gb|AAS74184.1| 5-HT1A [Drosophila melanogaster] gb|AAS74194.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74236.1| 5-HT1A [Drosophila melanogaster] gb|AAS74326.1| 5-HT1A [Drosophila mela...nogaster] gb|AAS74372.1| 5-HT1A [Drosophila melanogaster] AAS74184.1 1e-177 97% ...

Apoplejía, Convulsiones, Epilepsia, Heteroplasmia, MELAS, Migraña, Mutación, mtDNA Comportamiento de la mutación mtDNA A3243G en dos familias antioqueñas de pacientes diagnosticados con el síndrome MELAS

Directory of Open Access Journals (Sweden)

Gabriel Bedoya Berrío

2010-02-01

Full Text Available

Mitochondrial DNA mutations cause mitochondrial cytopathies. Among them Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes

(MELA is the commonest. The transition 3243A>G in the Leucine tRNA is present in 80% of the patients.

Heteroplasmy is observed in mitochondrial cytopathies, characterized by the coexistence of mutant and wild type molecules in a cell. Depending on the level of heteroplasmy, function and clinical manifestations might result affected.

Objective: To test the degree of heteroplasmy of the mutation 3243G on its expression (syntoms and nuclear-variants dependence.