213 research outputs found
Impact of sensory differences on consumer acceptability of yoghurt and yoghurt-like products
8 pages, 5 tables, 6 figures.-- Available online 7 October 2010.The aim of this work was to obtain information about how perceptible sensory differences affect consumer acceptability for yoghurt and a yoghurt-like product. Descriptive sensory profiles of six commercial samples, three of plain yoghurt and three of plain fermented milk, were determined using a trained panel (n = 10). Sample acceptance was determined by a group of consumers (n = 120). Initially, two groups of consumers were identified using Cluster analyses. For one group 46 (38%) of the consumers, variability in sensory attributes did not affect sample acceptability. For the second group, of 74 (62%) of the consumers, variability in sensory attributes had a significant effect and three consumer subgroups with different preference criteria were detected. Partial least squares regression was used to determine the sensory factors driving liking/disliking for each consumer subgroup. The information obtained can be important in predicting or explaining the market response to these types of products.MICINN of Spain for financial support (Project AGL 2007-63444) and Fondo Social Europeo for financing the contract of author S. Bayarri in the program I3P from CSIC.Peer reviewe
Filamin C-related myopathies: pathology and mechanisms
The term filaminopathy was introduced after a truncating mutation in the dimerization domain of filamin C (FLNc) was shown to be responsible for a devastating muscle disease. Subsequently, the same mutation was found in patients from diverse ethnical origins, indicating that this specific alteration is a mutational hot spot. Patients initially present with proximal muscle weakness, while distal and respiratory muscles become affected with disease progression. Muscle biopsies of these patients show typical signs of myofibrillar myopathy, including disintegration of myofibrils and aggregation of several proteins into distinct intracellular deposits. Highly similar phenotypes were observed in patients with other mutations in Ig-like domains of FLNc that result in expression of a noxious protein. Biochemical and biophysical studies showed that the mutated domains acquire an abnormal structure causing decreased stability and eventually becoming a seed for abnormal aggregation with other proteins. The disease usually presents only after the fourth decade of life possibly as a result of ageing-related impairments in the machinery that is responsible for disposal of damaged proteins. This is confirmed by mutations in components of this machinery that cause a highly similar phenotype. Transfection studies of cultured muscle cells reflect the events observed in patient muscles and, therefore, may provide a helpful model for testing future dedicated therapeutic strategies. More recently, FLNC mutations were also found in families with a distal myopathy phenotype, caused either by mutations in the actin-binding domain of FLNc that result in increased actin-binding and non-specific myopathic abnormalities without myofibrillar myopathy pathology, or a nonsense mutation in the rod domain that leads to RNA instability, haploinsufficiency with decreased expression levels of FLNc in the muscle fibers and myofibrillar abnormalities, but not to the formation of desmin-positive protein aggregates required for the diagnosis of myofibrillar myopathy
A metastable subproteome underlies inclusion formation in muscle proteinopathies
Protein aggregation is a pathological feature of neurodegenerative disorders. We previously demonstrated that protein inclusions in the brain are composed of supersaturated proteins, which are abundant and aggregation-prone, and form a metastable subproteome. It is not yet clear, however, whether this phenomenon is also associated with non-neuronal protein conformational disorders. To respond to this question, we analyzed proteomic datasets from biopsies of patients with genetic and acquired protein aggregate myopathy (PAM) by quantifying the changes in composition, concentration and aggregation propensity of proteins in the fibers containing inclusions and those surrounding them. We found that a metastable subproteome is present in skeletal muscle from healthy patients. The expression of this subproteome escalate as proteomic samples are taken more proximal to the pathologic inclusion, eventually exceeding its solubility limits and aggregating. While most supersaturated proteins decrease or maintain steady abundance across healthy fibers and inclusion-containing fibers, proteins within the metastable subproteome rise in abundance, suggesting that they escape regulation. Taken together, our results show in the context of a human conformational disorder that the supersaturation of a metastable subproteome underlies widespread aggregation and correlates with the histopathological state of the tissue
Исследование кинетики процесса полимеризации 5-норборнен-2,3дикарбоксимид-n-метил ацетата
Previous family studies revealed a large number of calpain 3 (CAPN3) mutations that cause recessive forms of limb girdle muscular dystrophy (LGMD2A) with selective atrophy of the proximal limb muscles. Correlations between the nature and site of a particular mutation and its corresponding phenotype, however, can only be established from homozygous mutations, which are particularly rare in the alternatively spliced NS, IS1 and IS2 regions of CAPN3. Here we identified a sibling pair with LGMD2A-type muscular dystrophy caused by a homozygous Ser606Leu (S606L) substitution in the IS2 linker domain. Normal protein levels, unaltered myofibrillar targeting and conserved calcium-induced autocatalytic activity of the mutated protein could be demonstrated in muscle biopsies from one patient. Despite this inconspicuous modification of the IS2 linker between domains III and IV, both patients developed signs and symptoms of the disease within their second decade of life. The unexpected severity of the clinical manifestation points to the high relevance of the calpain 3-specific IS2 segment between domains III and IV. We conclude that the structural motif around the Ser606 residue represents an important functional site that may regulate the transient activation and limited proteolysis of calpain 3
Scapuloperoneal syndrome type Kaeser and a wide phenotypic spectrum of adult-onset, dominant myopathies are associated with the desmin mutation R350P
In 1965, an adult-onset, autosomal dominant disorder with a peculiar scapuloperoneal distribution of weakness and atrophy was described in a large, multi-generation kindred and named ‘scapuloperoneal syndrome type Kaeser' (OMIM #181400). By genetic analysis of the original kindred, we discovered a heterozygous missense mutation of the desmin gene (R350P) cosegregating with the disorder. Moreover, we detected DES R350P in four unrelated German families allowing for genotype-phenotype correlations in a total of 15 patients carrying the same mutation. Large clinical variability was recognized, even within the same family, ranging from scapuloperoneal (n = 2, 12%), limb girdle (n = 10, 60%) and distal phenotypes (n = 3, 18%) with variable cardiac (n = 7, 41%) or respiratory involvement (n = 7, 41%). Facial weakness, dysphagia and gynaecomastia were frequent additional symptoms. Overall and within each family, affected men seemingly bear a higher risk of sudden, cardiac death as compared to affected women. Moreover, histological and immunohistochemical examination of muscle biopsy specimens revealed a wide spectrum of findings ranging from near normal or unspecific pathology to typical, myofibrillar changes with accumulation of desmin. This study reveals that the clinical and pathological variability generally observed in desminopathies may not be attributed to the nature of the DES mutation alone, but may be influenced by additional genetic and epigenetic factors such as gender. In addition, mutations of the desmin gene should be considered early in the diagnostic work-up of any adult-onset, dominant myopathy, even if specific myofibrillar pathology is absen
New insights into the protein aggregation pathology in myotilinopathy by combined proteomic and immunolocalization analyses
Introduction: Myofibrillar myopathies are characterized by progressive muscle weakness and impressive abnormal protein aggregation in muscle fibers. In about 10 % of patients, the disease is caused by mutations in the MYOT gene encoding myotilin. The aim of our study was to decipher the composition of protein deposits in myotilinopathy to get new information about aggregate pathology. Results: Skeletal muscle samples from 15 myotilinopathy patients were included in the study. Aggregate and control samples were collected from muscle sections by laser microdissection and subsequently analyzed by a highly sensitive proteomic approach that enables a relative protein quantification. In total 1002 different proteins were detected. Seventy-six proteins showed a significant over-representation in aggregate samples including 66 newly identified aggregate proteins. Z-disc-associated proteins were the most abundant aggregate components, followed by sarcolemmal and extracellular matrix proteins, proteins involved in protein quality control and degradation, and proteins with a function in actin dynamics or cytoskeletal transport. Forty over-represented proteins were evaluated by immunolocalization studies. These analyses validated our mass spectrometric data and revealed different regions of protein accumulation in abnormal muscle fibers. Comparison of data from our proteomic analysis in myotilinopathy with findings in other myofibrillar myopathy subtypes indicates a characteristic basic pattern of aggregate composition and resulted in identification of a highly sensitive and specific diagnostic marker for myotilinopathy. Conclusions: Our findings i) indicate that main protein components of aggregates belong to a network of interacting proteins, ii) provide new insights into the complex regulation of protein degradation in myotilinopathy that may be relevant for new treatment strategies, iii) imply a combination of a toxic gain-of-function leading to myotilin-positive protein aggregates and a loss-of-function caused by a shift in subcellular distribution with a deficiency of myotilin at Z-discs that impairs the integrity of myofibrils, and iv) demonstrate that proteomic analysis can be helpful in differential diagnosis of protein aggregate myopathies
New insights into the protein aggregation pathology in myotilinopathy by combined proteomic and immunolocalization analyses
Introduction: Myofibrillar myopathies are characterized by progressive muscle weakness and impressive abnormal protein aggregation in muscle fibers. In about 10 % of patients, the disease is caused by mutations in the MYOT gene encoding myotilin. The aim of our study was to decipher the composition of protein deposits in myotilinopathy to get new information about aggregate pathology. Results: Skeletal muscle samples from 15 myotilinopathy patients were included in the study. Aggregate and control samples were collected from muscle sections by laser microdissection and subsequently analyzed by a highly sensitive proteomic approach that enables a relative protein quantification. In total 1002 different proteins were detected. Seventy-six proteins showed a significant over-representation in aggregate samples including 66 newly identified aggregate proteins. Z-disc-associated proteins were the most abundant aggregate components, followed by sarcolemmal and extracellular matrix proteins, proteins involved in protein quality control and degradation, and proteins with a function in actin dynamics or cytoskeletal transport. Forty over-represented proteins were evaluated by immunolocalization studies. These analyses validated our mass spectrometric data and revealed different regions of protein accumulation in abnormal muscle fibers. Comparison of data from our proteomic analysis in myotilinopathy with findings in other myofibrillar myopathy subtypes indicates a characteristic basic pattern of aggregate composition and resulted in identification of a highly sensitive and specific diagnostic marker for myotilinopathy. Conclusions: Our findings i) indicate that main protein components of aggregates belong to a network of interacting proteins, ii) provide new insights into the complex regulation of protein degradation in myotilinopathy that may be relevant for new treatment strategies, iii) imply a combination of a toxic gain-of-function leading to myotilin-positive protein aggregates and a loss-of-function caused by a shift in subcellular distribution with a deficiency of myotilin at Z-discs that impairs the integrity of myofibrils, and iv) demonstrate that proteomic analysis can be helpful in differential diagnosis of protein aggregate myopathies
Удаление аммиака из водных растворов с использованием цеолитов
Объектом исследования являются природные и модифицированные цеолиты Чугуевского, Шивыртуйского, Холинского и Сокирницкого месторождений с различным гранулометрическим составом. Цель работы – изучение процесса сорбции, основанного на применении природного и модифицированного цеолита, для удаления аммиака и ионов аммония. В процессе исследования проводились эксперименты на выявление сорбционной способности природных и модифицированных цеолитов к аммиаку и ионам аммония в водных растворах, сравнение эффективности очистки воды данными цеолитами. В результате исследования был выбран цеолит, имеющий наибольший коэффициент извлечения аммиака и ионов аммония из водных растворов и предложена дополнительная стадия очистки воды для аппаратурно-технологической схемы умягчения подземных вод с использованием генератора микропузырьковой обработки и гидроксида аммония. Область применения: цеолитный фильтр может быть использован в установках водоподготовки для местного водоснабжения. Предложенный способ очистки воды является экономически выгодным ввиду маленькой себестоимости сорбента, простоты эксплуатации, регенерации и утилизации использованного материала.Object of research are natural and modified zeolites Chuguev, Chivyrkuyskogo, of Mine and of Sokyrnytsya deposits of different granulometric composition. The aim of this work is the study of the sorption process based on the use of natural and modified zeolite for removing ammonia and ammonium ions. During the study, experiments were conducted to identify the sorption capacity of natural and modified zeolites to ammonia and ammonium ions in aqueous solutions, comparison of effectiveness of water treatment, these zeolites. The study was selected zeolite that has the highest recovery rate of ammonia and ammonium ions from aqueous solutions and proposed an additional stage of purification of water for the equipment-technological scheme of softening of underground waters with the use of a microbubble generator treatment and ammonium hydroxide. Applications: zeolite filter can be used in water treatment plants for local water supply. The proposed method of water treatment is economically advantageous due to the small cost of the sorbent, ease of operation, regeneration and disposal of used material
Hepatic mitochondrial dysfunction in Friedreich Ataxia
<p>Abstract</p> <p>Background</p> <p>Mitochondrial dysfunction due to respiratory chain impairment is a key feature in pathogenesis of Friedreich ataxia. Friedreich ataxia affects the nervous system, heart and pancreas.</p> <p>Methods</p> <p>We assessed hepatic mitochondrial function by <sup>13</sup>C-methionine-breath-test in 16 Friedreich ataxia patients and matched healthy controls.</p> <p>Results</p> <p>Patients exhaled significantly smaller amounts of <sup>13</sup>CO<sub>2 </sub>over 90 minutes. Maximal exhaled percentage dose of <sup>13</sup>CO<sub>2 </sub>recovery was reduced compared to controls.</p> <p>Conclusions</p> <p><sup>13</sup>C-methionine-breath-test indicates subclinical hepatic mitochondrial dysfunction in Friedreich ataxia but did not correlate with GAA repeat lengths, disease duration or disease severity.</p
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