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1.
Orphanet J Rare Dis ; 17(1): 193, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35550173

RESUMO

BACKGROUND: Lysosomal acid lipase deficiency (LALD) is an ultra-rare, inherited metabolic disease within the category of lysosomal storage disorders, affecting an infant's ability to metabolise cholesterol. Developments in treatment, including Enzyme Replacement Therapy, have proven successful, with some children living for a number of years with treatment, although the future still remains unknown. The aim of this study was to explore the lived experiences of parents of children with LALD. MAIN TEXT: Participants were recruited from across the United Kingdom between 2020 and 2021. Eight parents (five mothers and three fathers) whose child had a confirmed diagnosis of LALD were interviewed. Data collected from the semi-structured interviews were audio-record, transcribed and analysed using Interpretative Phenomenological Analysis (IPA). Three superordinate and nine subordinate themes emerged from the data: (1) Uncertainty-a double-edged sword (plunged into an uncertain world, living life with worry and walking the tightrope of stability), (2) Powerless against a shared battle with LALD (a helpless parent, a joint battle, protection against distress and a vulnerable parent needing help) and 3) Accepting a life with LALD (coming to terms with a diagnosis of LALD and a hidden condition). CONCLUSIONS: The findings of this study highlight that the diagnosis of LALD proves to be a very challenging and emotionally distressing time in parents' lives, with increased uncertainty about what the future will hold for their child. This study signified the importance of healthcare pathways and service provisions to support parents and their children throughout diagnosis and beyond.


Assuntos
Doença de Wolman , Criança , Terapia de Reposição de Enzimas , Feminino , Humanos , Lactente , Mães , Pais/psicologia , Pesquisa Qualitativa , Doença de Wolman/diagnóstico , Doença de Wolman
2.
Mol Genet Metab ; 129(2): 98-105, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31383595

RESUMO

The outcome of 110 patients with paediatric onset mucopolysaccharidosis II (MPS II) since the commercial introduction of enzyme replacement therapy (ERT) in England in 2007 is reported. Median length of follow up was 10 years 3 months (range = 1 y 2 m to 18 years 6 month). 78 patients were treated with ERT, 18 had no ERT or disease modifying treatment 7 had haematopoietic stem cell transplant, 4 experimental intrathecal therapy and 3 were lost to follow up. There is clear evidence of improved survival (median age of death of ERT treated (n = 16) = 15.13 years (range = 9.53 to 20.58 y), and untreated (n = 17) = 11.43 y (0.5 to 19.13 y) p = .0005). Early introduction of ERT improved respiratory outcome at 16 years, the median FVC (% predicted) of those in whom ERT initiated <8 years = 69% (range = 34-86%) and 48% (25-108) (p = .045) in those started >8 years. However, ERT appears to have minimal impact on hearing, carpal tunnel syndrome or progression of cardiac valvular disease. Cardiac valvular disease occurred in 18/46 (40%), with progression occurring most frequently in the aortic valve 13/46 (28%). The lack of requirement for neurosurgical intervention in the first 8 years of life suggests that targeted imaging based on clinical symptomology would be safe in this age group after baseline assessments. There is also emerging evidence that the neurological phenotype is more nuanced than the previously recognized dichotomy of severe and attenuated phenotypes in patients presenting in early childhood.


Assuntos
Terapia de Reposição de Enzimas , Mucopolissacaridose II/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Coleta de Dados , Progressão da Doença , Inglaterra , Seguimentos , Humanos , Lactente , Mucopolissacaridose II/mortalidade , Fenótipo , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
3.
JIMD Rep ; 44: 79-84, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30097991

RESUMO

Lathosterolosis is a rare defect of cholesterol synthesis. Only four previous cases have been reported, two of whom were siblings. We report a fifth patient, with a relatively mild phenotype. He presented at 5 years of age with bilateral posterior cataracts, which were managed with lensectomies and intraocular lens implants. He also had learning difficulties, with a full-scale IQ of 64 at 11 years of age. His head circumference is between the 0.4th and 2nd centiles, and he has mild hypotonia and subtle dysmorphism (a high-arched palate, anteverted nostrils, long philtrum and clinodactyly of toes). The diagnosis was established after sequencing a panel of genes associated with cataracts, which revealed compound heterozygous SC5D mutations: c.479C>G p.(Pro160Arg) and c.630C>A p.(Asp210Glu). The plasma lathosterol concentration was markedly raised at 219.8 µmol/L (control range 0.53-16.0), confirming the diagnosis. The c.630C>A p.(Asp210Glu) mutation has been reported in one previous patient, who also had a relatively mild phenotype (Ho et al., JIMD Rep 12:129-134, 2014). The mutation leads to a relatively conservative amino acid substitution, consistent with some residual enzyme activity. Our patient's family did not notice any benefit from treatment with simvastatin. In summary, milder patients with lathosterolosis may present with learning difficulties, cataracts and very subtle dysmorphism. The diagnosis will be missed unless plasma sterols are analysed or relevant genes sequenced.

4.
J Hum Genet ; 63(6): 707-716, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29618761

RESUMO

Seven subunits of the mitochondrial contact site and cristae junction (CJ) organizing system (MICOS) in humans have been recently described in function and structure. QIL1 (also named MIC13) is a small complex that is crucial for the maintenance and assembling of MICOS. A novel mutation of an essential splice site in the C19orf70 gene encoding QIL1 induces severe mitochondrial encephalopathy, hepatopathy and lactate acidosis consistent with psychomotor retardation. In addition, bilateral kidney stones were observed. Disassembly of MICOS complex subunits displays lack of MIC10-MIC26-MIC27-QIL1 subcomplex, resulting in aberrant cristae structure and a loss of cristae junctions and contact sites. In liver and muscle tissue, the activity of the respiratory chain complexes (OXPHOS) was severely impaired. Defects in MICOS complex do not only affect mitochondrial architecture, but also mitochondrial fusion, metabolic signalling, lipid trafficking and cellular electric homeostasis.


Assuntos
Genes Letais , Hepatopatias/genética , Proteínas de Membrana/genética , Mitocôndrias/metabolismo , Encefalomiopatias Mitocondriais/genética , Proteínas Mitocondriais/genética , Mutação , Desempenho Psicomotor , Acidose Láctica/complicações , Encéfalo/diagnóstico por imagem , Transporte de Elétrons , Evolução Fatal , Feminino , Humanos , Lactente , Recém-Nascido , Cálculos Renais/complicações , Fígado/metabolismo , Hepatopatias/complicações , Hepatopatias/fisiopatologia , Imageamento por Ressonância Magnética , Encefalomiopatias Mitocondriais/complicações , Encefalomiopatias Mitocondriais/diagnóstico por imagem , Encefalomiopatias Mitocondriais/fisiopatologia , Músculos/metabolismo , Fases de Leitura Aberta , Fosforilação Oxidativa , Sítios de Splice de RNA
6.
JIMD Rep ; 26: 21-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26238249

RESUMO

Congenital disorders of glycosylation form a rapidly growing group of inherited metabolic diseases. As glycosylation affects proteins all over the organism, a mutation in a single gene leads to a multisystemic disorder. We describe a patient with TMEM165-CDG with facial dysmorphism, nephrotic syndrome, cardiac defects, enlarged cerebral ventricles, feeding problems, and neurological involvement. Having confirmed the diagnosis via prenatal diagnostics, we were able to observe the glycosylation right from birth, finding a pathological pattern already on the first day of life. Within the next few weeks, hypoglycosylation progressed to less sialylated and then also to hypogalactosylated isoforms. On the whole, there has not been much published evidence concerning postnatal glycosylation and its adaptational process. This is the first paper reporting changes in glycosylation patterns over the first postnatal weeks in TMEM165-CDG.

7.
Int J Tuberc Lung Dis ; 19(11): 1271-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26467577

RESUMO

The Ebola outbreak that started in late 2013 is by far the largest and most sustained in history. It occurred in a part of the world where pre-existing health systems were already fragile, and these deteriorated further during the epidemic due to a large number of health worker deaths; temporary or permanent closure of health facilities; non-payment of health workers; intrinsic fear of contracting or being stigmatised by Ebola among the population, which negatively influenced health-seeking behaviour; enforced quarantine of Ebola-affected communities, restricting the access of vulnerable individuals to health facilities; and late response by the international community. There are also reports of drug and consumable stockouts due to deficiencies in the procurement and supply chain as a result of overriding Ebola-related priorities. Providing tuberculosis (TB) care and achieving favourable treatment outcomes require a fully functioning health system, accurate patient tracking and high patient adherence to treatment. Furthermore, as Ebola is easily transmitted through body fluids, the use of needles-essential for TB diagnosis and treatment-needs to be avoided during an outbreak. We highlight ways in which a sustained Ebola outbreak could jeopardise TB activities and suggest pre-emptive preventive measures while awaiting operational research evidence.


Assuntos
Surtos de Doenças , Pessoal de Saúde/psicologia , Doença pelo Vírus Ebola/epidemiologia , Tuberculose/epidemiologia , Pessoal de Saúde/economia , Acessibilidade aos Serviços de Saúde , Humanos , Pesquisa Operacional , Estigma Social , Tuberculose/prevenção & controle
8.
J Inherit Metab Dis ; 38(5): 931-40, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25778940

RESUMO

Congenital disorders of glycosylation (CDG) are a group of hereditary metabolic diseases characterized by abnormal glycosylation of proteins and lipids. Often, multisystem disorders with central nervous system involvement and a large variety of clinical symptoms occur. The main characteristics are developmental delay, seizures, and ataxia. In this paper we report the clinical and biochemical characteristics of a 5-year-old girl with a defective galactosylation of N-glycans, resulting in developmental delay, muscular hypotonia, epileptic seizures, inverted nipples, and visual impairment. Next generation sequencing revealed a de novo mutation (c.797G > T, p.G266V) in the X-chromosomal gene SLC35A2 (solute carrier family 35, UDP-galactose transporter, member A2; MIM 300896). While this mutation was found heterozygous, random X-inactivation of the normal allele will lead to loss of normal SLC35A2 activity in respective cells. The functional relevance of the mutation was demonstrated by complementation of UGT-deficient MDCK-RCA(r) and CHO-Lec8 cells by normal UGT-expression construct but not by the mutant version. The effect of dietary galactose supplementation on glycosylation was investigated, showing a nearly complete normalization of transferrin glycosylation.


Assuntos
Defeitos Congênitos da Glicosilação/genética , Defeitos Congênitos da Glicosilação/terapia , Proteínas de Transporte de Monossacarídeos/genética , Animais , Células CHO , Pré-Escolar , Cricetinae , Cricetulus , Análise Mutacional de DNA , Cães , Feminino , Galactose/uso terapêutico , Humanos , Células Madin Darby de Rim Canino , Proteínas de Transporte de Monossacarídeos/deficiência , Fenótipo
9.
J Anim Sci ; 92(9): 4108-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24987071

RESUMO

Tail docking of feedlot cattle is a management practice used in some confined, slatted-floor feedlots of the midwestern United States. Justification for tail docking in these management systems is to reduce tail injuries and their sequelae and improve performance, but limited evidence exists to support these claims. The primary objective of this study was to determine the effect of tail docking on performance, carcass traits, and health parameters after tail docking in feedlot cattle raised in slatted-floor feedlots. Three separate trials were performed. Trial 1 consisted of 140 Angus-cross (370-kg) yearling steers that spent 144 to 160 days on feed (DOF). Trial 2 consisted of 137 Angus-cross (255-kg) weaned steers that spent 232 DOF. Trial 3 consisted of 102 Holstein steers (370 kg) that spent 185 to 232 DOF. Cattle were randomly assigned to 1 of 2 treatment groups: docked (DK) or control (CN). All steers received an epidural following surgical preparation of the sacrococcygeal area and postoperative intravenous flunixin meglumine. Approximately two-thirds of the tail of DK calves was removed and an elastrator band was placed near the tail tip for hemostasis. Performance parameters collected included daily gain, final weight, feed intake, and feed efficiency. Carcass data included HCW, subcutaneous fat thickness, LM area, KPH percent, marbling, USDA yield grade, and USDA quality grade. Morbidity, mortality, incidence of lameness, and incidence of tail lesions were recorded. Across all 3 trials, there was no significant effect (P < 0.05) of treatment on performance parameters, carcass traits, or health parameters. In all 3 trials, tail tip injuries occurred in 60 to 76% of undocked (CN) calves, developed while living in the slatted-floor environment, compared to 100% of DK calves, whose injuries were a result of the tail docking procedure. We were unable to identify a performance or significant health advantage to tail docking. However, tail tip injuries still occur in cattle raised in slatted-floor facilities. Because of the animal welfare issues associated with tail docking and tail injuries, we recommend pursuing alternative solutions to reducing the incidence of tail tip injury in feedlot cattle housed in confined slatted-floor facilities.


Assuntos
Amputação Cirúrgica/veterinária , Bem-Estar do Animal/normas , Bovinos/crescimento & desenvolvimento , Abrigo para Animais , Cauda/cirurgia , Administração Intravenosa , Animais , Peso Corporal , Clonixina/administração & dosagem , Clonixina/análogos & derivados , Gordura Subcutânea
10.
Gene ; 534(2): 345-51, 2014 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-24157261

RESUMO

Congenital disorders of glycosylation (CDG) are a growing group of inherited metabolic disorders where enzymatic defects in the formation or processing of glycolipids and/or glycoproteins lead to variety of different diseases. The deficiency of GDP-Man:GlcNAc2-PP-dolichol mannosyltransferase, encoded by the human ortholog of ALG1 from yeast, is known as ALG1-CDG (CDG-Ik). The phenotypical, molecular and biochemical analysis of a severely affected ALG1-CDG patient is the focus of this paper. The patient's main symptoms were feeding problems and diarrhea, profound hypoproteinemia with massive ascites, muscular hypertonia, seizures refractory to treatment, recurrent episodes of apnoea, cardiac and hepatic involvement and coagulation anomalies. Compound heterozygosity for the mutations c.1145T>C (M382T) and c.1312C>T (R438W) was detected in the patient's ALG1-coding sequence. In contrast to a previously reported speculation on R438W we confirmed both mutations as disease-causing in ALG1-CDG.


Assuntos
Defeitos Congênitos da Glicosilação/genética , Manosiltransferases/genética , Mutação , Sequência de Aminoácidos , Evolução Fatal , Glicosilação , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Alinhamento de Sequência
11.
Nutr Metab Cardiovasc Dis ; 23(8): 732-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22795295

RESUMO

BACKGROUND AND AIM: The complete absence of the lysosomal acid lipase (LAL) enzyme function causes Wolman's Disease that is fatal within the first six months of life. Subtotal defects cause Cholesteryl ester storage disease (CESD), an autosomal recessive disorder leading to hepatic steatosis, fibrosis, micronodular cirrhosis, combined hyperlipidemia with low HDL-cholesterol, increased risk for atherosclerosis, premature death. Since the frequency of the Exon 8 splice junction mutation (c.894 G > A, E8SJM), the CESD leading mutation, is not rare in the general population (allele frequency 0.0025), we investigated the impact of this mutation on serum lipid profile in E8SJM carriers. METHODS AND RESULTS: We collected E8SJM carriers both form genetic study-population analysis and from Outpatient Lipid Clinics and then we assessed their serum lipid profile. We found thirteen individuals heterozygote for E8SJM. Most of them were Germans, three Spanish and two Italian. We found a significant increase in total cholesterol levels in both sexes with E8SJM mutation, leading to a significant increase in LDL cholesterol in males. CONCLUSIONS: Our results show that LAL E8SJM carriers have an alteration in lipid profile with a Polygenic Hypercholesterolemia phenotype, leading to an increase in cardiovascular risk profile.


Assuntos
Colesterol/sangue , Heterozigoto , Mutação , Esterol Esterase/genética , Doenças Cardiovasculares/genética , Estudos de Casos e Controles , Feminino , Alemanha , Humanos , Itália , Masculino , Fenótipo , Fatores de Risco , Espanha , População Branca
12.
Mol Genet Metab ; 108(1): 82-4, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23219289

RESUMO

Niemann Pick Type C2 (NPC2) is a rare autosomal recessive disease caused by mutations in the NPC2 gene (OMIM 601015). Clinically, NPC2 presents in most cases in the neonatal period with inflammatory lung disease, which may lead to death in the first year. If patients survive the neonatal period, they may develop a severe neurological disease. Here we present the developmental and neurological follow up at 5 years of age of a child with NPC2 successfully treated with allogenic bone marrow transplantation (BMT) at the age of 16 months. A homozygous p.E20X sequence variation previously associated with a severe phenotype was identified. In contrast to the previously reported patients with the same mutations, our patient has no respiratory compromise and has made some developmental progress (especially gross motor), though is significantly delayed (particularly in speech and language). Haematopoietic stem cell transplantation (HSCT) could be considered for patients with this mutation as long as performed early in the course of the disease.


Assuntos
Transplante de Medula Óssea , Doença de Niemann-Pick Tipo C/cirurgia , Evolução Fatal , Humanos , Lactente , Recém-Nascido , Doença de Niemann-Pick Tipo C/fisiopatologia , Transplante Homólogo
13.
Mol Genet Metab ; 105(4): 634-41, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22304930

RESUMO

Congenital disorders of glycosylation (CDG) are caused by enzymatic defects of the formation or processing of lipid-linked oligosaccharides and glycoproteins. Since the majority of proteins is glycosylated, a defect in a singular CDG enzyme leads to a multisytemic disease with secondary malfunction of thousands of proteins. CDG-Ij (DPAGT1-CDG) is caused by a defect of the human DPAGT1 (UDP-GlcNAc: Dolichol Phosphate N-Acetylglucosamine-1-Phosphotransferase), catalyzing the first step of N-linked glycosylation. So far the clinical phenotype of only one CDG-Ij patient has been described. The patient showed severe muscular hypotonia, intractable seizures, developmental delay, mental retardation, microcephaly and exotropia. Molecular studies of this patient revealed the heterozygous mutation c.660A>G (Y170C; paternal) in combination with an uncharacterized splicing defect (maternal). Two further mutations, c.890A>T (I297F) and c.162-8G>A as a splicing defect were detected when analyzing DPAGT1 in two affected siblings of a second family. We report two new patients with the novel homozygous mutation, c.341C>G (A114 G), causing a severe clinical phenotype, characterized by hyperexcitability, intractable seizures, bilateral cataracts, progressive microcephaly and muscular hypotonia. Both our patients died within their first year of life. With the discovery of this novel mutation and a detailed clinical description we extend the clinical features of CDG-Ij in order to improve early detection of this disease.


Assuntos
Defeitos Congênitos da Glicosilação/enzimologia , Defeitos Congênitos da Glicosilação/genética , Mutação/genética , Doenças Raras/enzimologia , Doenças Raras/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Adulto , Sequência de Aminoácidos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Feminino , Fibroblastos/citologia , Fibroblastos/enzimologia , Glicosilação , Homozigoto , Humanos , Imunoprecipitação , Recém-Nascido , Lipopolissacarídeos/metabolismo , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Pele/citologia , Pele/enzimologia
14.
Mol Genet Metab ; 105(4): 642-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22304929

RESUMO

Congenital disorders of glycosylation (CDG) are caused by a dysfunction of glycosylation, an essential step in the manufacturing process of glycoproteins. This paper focuses on a 6-year-old patient with a new type of CDG-I caused by a defect of the steroid 5α reductase type 3 gene (SRD5A3). The clinical features were psychomotor retardation, pathological nystagmus, slight muscular hypotonia and microcephaly. SRD5A3 was recently identified encoding the polyprenol reductase, an enzyme catalyzing the final step of the biosynthesis of dolichol, which is required for the assembly of the glycans needed for N-glycosylation. Although an early homozygous stop-codon (c.57G>A [W19X]) with no functional protein was found in the patient, about 70% of transferrin (Tf) was correctly glycosylated. Quantification of dolichol and unreduced polyprenol in the patient's fibroblasts demonstrated a high polyprenol/dolichol ratio with normal amounts of dolichol, indicating that high polyprenol levels might compete with dolichol for the initiation of N-glycan assembly but without supporting normal glycosylation and that there must be an alternative pathway for dolichol biosynthesis.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Defeitos Congênitos da Glicosilação/enzimologia , Defeitos Congênitos da Glicosilação/genética , Proteínas de Membrana/genética , Mutação/genética , Pentanóis/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Defeitos Congênitos da Glicosilação/diagnóstico , Dolicóis/metabolismo , Eletroforese em Gel de Poliacrilamida , Feminino , Fibroblastos , Teste de Complementação Genética , Glicosilação , Homozigoto , Humanos , Imunoprecipitação , Recém-Nascido , Focalização Isoelétrica , Masculino , Linhagem
15.
Adv Appl Microbiol ; 71: 149-84, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20378054

RESUMO

Recent threats posed by pathogenic microorganisms in food, recreational waters, and as agents of bioterror have underscored the need for the development of more rapid, accurate, and cost-effective methods of microbial characterization and identification. This chapter focuses on the use of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to rapidly characterize and identify microorganisms through generation of characteristic fingerprints of intact cells. While most efforts have focused on bacteria, this technology has also been applied to fungi and viruses. Results of most studies suggest that MALDI-TOF MS can be used to rapidly and accurately characterize microorganisms. A variety of quantitative approaches have been employed in the analysis of MALDI-TOF MS fingerprints of microorganisms. The reproducibility of fingerprints of intact cells remains a primary concern and limitation associated with this approach. Protocols and instrumentation used have varied considerably and likely account for much of the variability in reproducibility reported. Key first steps to overcoming this limitation will be the development of standard approaches to quantifying reproducibility and the development of standard protocols for sample preparation and analysis.


Assuntos
Bactérias/classificação , Impressões Digitais de DNA/métodos , Fungos/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Vírus/classificação , Bactérias/genética , Fungos/genética , Reprodutibilidade dos Testes , Vírus/genética
16.
Folia Microbiol (Praha) ; 54(6): 521-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20140720

RESUMO

Inhibition of methanogenesis in ruminal cultures was attempted by hindering thiamine availability through its degradation by 'polyphenols' and competition for active sites on enzymes and transporters using thiamine structural analogs. Effects on fermentation were small and not consistently reversed by adding thiamine. Lack of major effects of the compounds evaluated could be due to intracellular synthesis of thiamine covering most requirements.


Assuntos
Rúmen/metabolismo , Rúmen/microbiologia , Tiamina/antagonistas & inibidores , Animais , Bovinos , Fermentação , Metano/antagonistas & inibidores
17.
J Anim Sci ; 86(1): 211-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17911226

RESUMO

The objective of this multiple-phase study was to determine the accuracy of an on-line near-infrared (NIR) spectral reflectance system to predict 14-d-aged cooked beef tenderness. In phase I, 292 carcasses (140 US Select, 152 US Choice) were selected (d 2) from 2 commercial beef processing facilities. After carcass selection, longissimus lumborum (LL) muscle sections (ribs 9 to 12) were individually identified, vacuum-packaged, and transported to the Oklahoma State University Meats Laboratory, where a 2.54-cm-thick steak (n = 1) was fabricated and stored in refrigerated conditions (1 degrees C +/- 1). Following a 30-min oxygenation period, a NIR spectral scan was obtained on the 12th-rib LL steak. Steaks (d 3) were individually vacuum-packaged and aged at 4 degrees C for a total of 14 d before cooking slice shear force (SSF) analysis. In phases II and III, 476 carcasses (258 US Select, 218 US Choice) were immediately NIR scanned after carcass presentation to in-plant USDA grading personnel. In a similar fashion, all LL steaks were aged (1 degrees C +/- 1) for 14 d before cooking (70 degrees C) and conducting SSF. Of the phase I and II samples, 39 (6.77%) were categorized as being tough (i.e., >/= 25 kg of SSF after the 14-d postmortem aging period). Of these 39 tough samples, 20 (3.7% error rate) were correctly placed in the 90% certification level. Another 10 tough samples were placed in the 80% certification level (2.0% error rate). The overall NIR certified tender group was 1.67 kg more tender (P < 0.05) than LL samples from the noncertified samples. When the NIR predicted samples to be tough, 10% of the samples were eliminated from the phase I and II LL populations at 90% certification. The population SSF mean improved in excess of 6.5 kg. For phase III, SSF evaluation by an independent third party indicated the NIR system was able to successfully sort tough from tender LL samples to 70% certification levels. It was concluded that NIR scanning offers an in-plant opportunity to sort carcasses into tenderness outcome groups for guaranteed-tender branded beef programs.


Assuntos
Culinária/métodos , Carne/análise , Carne/normas , Espectroscopia de Luz Próxima ao Infravermelho/veterinária , Animais , Bovinos
18.
Can J Microbiol ; 53(4): 496-503, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17612604

RESUMO

It was hypothesized that the addition of crotonic acid or 3-butenoic acid would relieve constraints in digestibility observed when methane formation is inhibited by lumazine, propynoic acid, or ethyl 2-butynoate. In six incubations, one of the three methanogenesis inhibitors, at three different concentrations, was combined with either crotonic acid or 3-butenoic acid at two different concentrations. A mixture of buffer and ruminal fluid (4:1) was incubated with grass hay in Erlenmeyer flasks for 72 h. Initial concentrations were 0, 0.6, and 1.2 mmol/L for lumazine; 0, 2, and 4 mmol/L for propynoic acid; and 0, 4, and 8 mmol/L for ethyl 2-butynoate. 15Nitrogen (N) incorporation was used as a microbial marker. All three methanogenesis inhibitors decreased proteolysis. Propynoic acid and ethyl 2-butynoate at 8 mmol/L also decreased the digestibility of organic matter and neutral detergent fibre. However, all three inhibitors of methanogenesis increased the production of microbial N through an improvement of synthetic efficiency. Crotonic acid and 3-butenoic acid were generally ineffective in compensating digestibility decreases caused by the inhibitors of methanogenesis. It is of interest to elucidate the mechanisms by which these compounds increased the efficiency of microbial N production. Lumazine and the addition of low levels of ethyl 2-butynoate could potentially benefit animal production by lowering methane emissions, decreasing ruminal proteolysis, and increasing microbial N production without affecting organic matter digestibility.


Assuntos
Metano/antagonistas & inibidores , Nitrogênio/metabolismo , Rúmen/metabolismo , Rúmen/microbiologia , Alcinos/química , Alcinos/farmacologia , Animais , Butiratos/química , Butiratos/metabolismo , Butiratos/farmacologia , Bovinos , Crotonatos/química , Crotonatos/farmacologia , Estrutura Molecular , Poaceae/metabolismo , Propionatos/química , Propionatos/farmacologia , Pteridinas/química , Pteridinas/farmacologia , Rúmen/química
19.
Eur J Clin Nutr ; 61(7): 896-905, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17228349

RESUMO

OBJECTIVE: We investigated the serum phytosterol responses of heterozygous relatives of sitosterolemia patients to diets enriched in phytosterols or stanols. DESIGN: Randomized double-blind crossover design. SETTING: Muenster, Germany. SUBJECTS: Eight heterozygous and 13 control subjects were recruited. One heterozygote and three controls dropped out. INTERVENTIONS: Seven heterozygotes and 10 controls received daily portions of margarine containing 2 g of plant sterols, 2 g of stanols or a control margarine for 6 weeks each in a randomized order. These phases were intercepted by wash-out periods of 6 weeks each. RESULTS: Compared to the control period, serum phytosterol concentrations increased overall by more than 20% when subjects consumed the plant sterol margarine (F((1,15))=8.719, P=0.01), with no significant difference between heterozygotes (mean +14.5 (s.d. 17.2) micromol/l, +23.0%) and controls (+4.9 (9.9) micromol/l, +20.5%; F((1,15))=2.168, P=0.162), but decreased when subjects consumed the stanol-enriched margarine (F((1,15))=12.124, P=0.003), again to a similar extent in heterozygotes (-34.2 (41.2) micromol/l, -54.2%) and controls (-12.2 (9.2) micromol/l, -50.6%; F((1,15))=2.729, P=0.119). The lowest total serum concentrations of cholesterol and phytosterols were seen after the diet enriched in stanols. Serum stanol concentrations increased on this diet, but on a very low level and never exceeded 0.05% of serum cholesterol levels in any subject. CONCLUSIONS: Serum phytosterol concentrations increased only moderately in heterozygotes consuming a diet enriched in phytosterols, indicating that they retained considerable capacity to excrete phytosterols even at higher intakes.


Assuntos
Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/sangue , Margarina , Fitosteróis , Sitosteroides/sangue , Adulto , Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Ésteres , Feminino , Alemanha , Humanos , Masculino , Fitosteróis/administração & dosagem , Fitosteróis/sangue , Sitosteroides/administração & dosagem , Esteróis/administração & dosagem , Esteróis/sangue
20.
Lett Appl Microbiol ; 42(6): 567-72, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16706893

RESUMO

AIMS: Inhibition of ruminal methanogenesis often causes accumulation of H(2), formate and ethanol, which are not energy substrates for ruminants. It was hypothesized that the addition of butyrate precursors would avoid the formation of these products and relocate electrons into butyrate. METHODS AND RESULTS: In four ruminal 24-h incubations, two inhibitors of methanogenesis, each at three different initial concentrations (0, 2 or 4 mmol l(-1) for propynoic acid, and 0, 4 or 8 mmol l(-1) for ethyl 2-butynoate), were combined with two butyrate precursors at two different initial concentrations (0 or 4 mmol l(-1) for crotonic acid or 3-butenoic acid). Ground lucerne hay was the substrate. Propynoic acid at 4 mmol l(-1) decreased CH(4) formation by more than two-thirds. Ethyl 2-butynoate at 8 mmol l(-1) suppressed methanogenesis by more than 90%. Butyrate precursors generally did not decrease the accumulation of H(2) and formate or ethanol production. CONCLUSIONS: Butyrate precursors were ineffective as electron acceptors because they were not completely converted to butyrate and were also metabolized through other pathways. SIGNIFICANCE AND IMPACT OF THE STUDY: Effectiveness of butyrate precursors may be improved by adding them to the fermentation continuously or by enhancing the kinetics of their conversion into butyrate.


Assuntos
Butiratos/metabolismo , Elétrons , Hidrogênio/metabolismo , Metano/antagonistas & inibidores , Rúmen/microbiologia , Alcinos/farmacologia , Animais , Butiratos/farmacologia , Bovinos , Crotonatos/farmacologia , Etanol/metabolismo , Fermentação , Formiatos/metabolismo , Propionatos/farmacologia
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