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The hexanucleotide repeat expansion GGGGCC (G4C2)n in the C9orf72 gene is the most common genetic abnormality associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recent findings suggest that dysfunction of nuclear-cytoplasmic trafficking could affect the transport of RNA binding proteins in C9orf72 ALS/FTD. Here, we provide evidence that the RNA editing enzyme adenosine deaminase acting on RNA 2 (ADAR2) is mislocalized in C9orf72 repeat expansion mediated ALS/FTD. ADAR2 is responsible for adenosine (A) to inosine (I) editing of double-stranded RNA, and its function has been shown to be essential for survival. Here we show the mislocalization of ADAR2 in human induced pluripotent stem cell-derived motor neurons (hiPSC-MNs) from C9orf72 patients, in mice expressing (G4C2)149, and in C9orf72 ALS/FTD patient postmortem tissue. As a consequence of this mislocalization we observe alterations in RNA editing in our model systems and across multiple brain regions. Analysis of editing at 408,580 known RNA editing sites indicates that there are vast RNA A to I editing aberrations in C9orf72-mediated ALS/FTD. These RNA editing aberrations are found in many cellular pathways, such as the ALS pathway and the crucial EIF2 signaling pathway. Our findings suggest that the mislocalization of ADAR2 in C9orf72 mediated ALS/FTD is responsible for the alteration of RNA processing events that may impact vast cellular functions, including the integrated stress response (ISR) and protein translation.
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Adenosina Desaminase/genética , Proteína C9orf72/genética , Edição de RNA/genética , Proteínas de Ligação a RNA/genética , Esclerose Lateral Amiotrófica/genética , Animais , Expansão das Repetições de DNA/genética , Demência Frontotemporal/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos Transgênicos , Doença de Pick/genéticaRESUMO
The original article was published erroneously without mentioning the support of the U.S.
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Muscular dystrophy is characterized by progressive skeletal muscle weakness and dystrophic muscle exhibits degeneration and regeneration of muscle cells, inflammation and fibrosis. Skeletal muscle fibrosis is an excessive deposition of components of the extracellular matrix including an accumulation of Collagen VI. We hypothesized that a reduction of Collagen VI in a muscular dystrophy model that presents with fibrosis would result in reduced muscle pathology and improved muscle function. To test this hypothesis, we crossed γ-sarcoglycan-null mice, a model of limb-girdle muscular dystrophy type 2C, with a Col6a2-deficient mouse model. We found that the resulting γ-sarcoglycan-null/Col6a2Δex5 mice indeed exhibit reduced muscle pathology compared with γ-sarcoglycan-null mice. Specifically, fewer muscle fibers are degenerating, fiber size varies less, Evans blue dye uptake is reduced and serum creatine kinase levels are lower. Surprisingly, in spite of this reduction in muscle pathology, muscle function is not significantly improved. In fact, grip strength and maximum isometric tetanic force are even lower in γ-sarcoglycan-null/Col6a2Δex5 mice than in γ-sarcoglycan-null mice. In conclusion, our results reveal that Collagen VI-mediated fibrosis contributes to skeletal muscle pathology in γ-sarcoglycan-null mice. Importantly, however, our data also demonstrate that a reduction in skeletal muscle pathology does not necessarily lead to an improvement of skeletal muscle function, and this should be considered in future translational studies.
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Colágeno Tipo VI/metabolismo , Regulação para Baixo , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/metabolismo , Sarcoglicanopatias/metabolismo , Animais , Camundongos , Camundongos Knockout , Distrofia Muscular Animal/patologia , Distrofia Muscular Animal/fisiopatologia , Sarcoglicanopatias/patologia , Sarcoglicanopatias/fisiopatologiaRESUMO
Toronto Public Health conducted a pilot project to assess the feasibility of menu labelling by independent restaurants. The pilot project was informed by consultations with the industry and other jurisdictions that have implemented a similar initiative. Public Health Dietitians worked closely with these restaurants to help them work toward posting calories and sodium on their menus. This paper reports on the findings of a feasibility assessment that took a mixed-methods approach resulting in a comprehensive process evaluation. Results showed that having highly motivated restaurants and early adopters of menu labelling is a necessary starting point. However, this alone is not sufficient to make voluntary menu labelling successful. It may be feasible only for select independent restaurants who: (i) are highly motivated and ready to make a substantial time commitment; (ii) value offering healthy food choices; (iii) have fairly standardized recipes to begin with; (iv) receive extensive specialized, individualized support; and (v) receive incentives, cost offsetting, and recognition. Full-scale implementation of a menu labelling program with Toronto independent restaurants was not justified given the current level of interest and capacity.
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Rotulagem de Alimentos , Planejamento de Cardápio , Restaurantes , Canadá , Comportamento de Escolha , Dieta , Estudos de Viabilidade , Preferências Alimentares , Humanos , Nutricionistas , Projetos Piloto , Saúde PúblicaRESUMO
OBJECTIVE: The purpose of this study is to better characterize the findings of esophagography after peroral endoscopic myotomy for achalasia. MATERIALS AND METHODS: We evaluated 25 patients who underwent peroral endoscopic myotomy for achalasia. The findings noted on pre- and postprocedural esophagrams were reviewed retrospectively and were correlated with clinical outcomes. RESULTS: None of the patients had esophageal perforation noted on esophagrams obtained after myotomy, and all but two patients had a hospital stay that lasted 1 day only. Esophagrams obtained on postoperative day 1 revealed endoscopic clips in 25 patients (100%), pneumoperitoneum in 18 (72%), retroperitoneal gas in 10 (40%), gastric pneumatosis in nine (36%), intramural dissections in seven (28%), and pneumomediastinum in four (16%). Repeat esophagrams obtained 3 weeks later for 22 of the patients revealed endoscopic clips in 16 patients (73%) and intramural dissections in five patients (23%), but the remaining findings had resolved. Eighteen patients (72%) had a successful myotomy and seven (28%) had suboptimal results on the basis of clinical outcomes. Observation of a distal esophageal width of 5 mm or less on postprocedural esophagrams was often associated with suboptimal results. CONCLUSION: Peroral endoscopic myotomy is a novel procedure that is less invasive than is laparoscopic Heller myotomy for the treatment of achalasia, with fewer complications and shorter recovery times. Radiologists should be aware of the findings expected on esophagography (including pneumoperitoneum, retroperitoneal gas, gastric pneumatosis, intramural dissections, and pneumomediastinum) and should also know that fluoroscopic studies may be helpful for predicting patient outcomes on the basis of the width of the distal esophagus after myotomy.
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Acalasia Esofágica/diagnóstico por imagem , Acalasia Esofágica/cirurgia , Esofagoscopia/métodos , Esôfago/diagnóstico por imagem , Cirurgia Endoscópica por Orifício Natural/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Introduction: Limb girdle muscular dystrophies (LGMDs) are a group of genetically heterogeneous autosomal conditions with some degree of phenotypic homogeneity. LGMD is defined as having onset >2 years of age with progressive proximal weakness, elevated serum creatine kinase levels and dystrophic features on muscle biopsy. Advances in massively parallel sequencing have led to a surge in genes linked to LGMD. Methods: The ClinGen Muscular Dystrophies and Myopathies gene curation expert panel (MDM GCEP, formerly Limb Girdle Muscular Dystrophy GCEP) convened to evaluate the strength of evidence supporting gene-disease relationships (GDR) using the ClinGen gene-disease clinical validity framework to evaluate 31 genes implicated in LGMD. Results: The GDR was exclusively LGMD for 17 genes, whereas an additional 14 genes were related to a broader phenotype encompassing congenital weakness. Four genes (CAPN3, COL6A1, COL6A2, COL6A3) were split into two separate disease entities, based on each displaying both dominant and recessive inheritance patterns, resulting in curation of 35 GDRs. Of these, 30 (86%) were classified as Definitive, 4 (11%) as Moderate and 1 (3%) as Limited. Two genes, POMGNT1 and DAG1, though definitively related to myopathy, currently have insufficient evidence to support a relationship specifically with LGMD. Conclusions: The expert-reviewed assertions on the clinical validity of genes implicated in LGMDs form an invaluable resource for clinicians and molecular geneticists. We encourage the global neuromuscular community to publish case-level data that help clarify disputed or novel LGMD associations.
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While motor and cortical neurons are affected in C9orf72 amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD), it remains largely unknown if and how non-neuronal cells induce or exacerbate neuronal damage. We differentiated C9orf72 ALS/FTD patient-derived induced pluripotent stem cells into microglia (iPSC-MG) and examined their intrinsic phenotypes. Similar to iPSC motor neurons, C9orf72 ALS/FTD iPSC-MG mono-cultures form G4C2 repeat RNA foci, exhibit reduced C9orf72 protein levels, and generate dipeptide repeat proteins. Healthy control and C9orf72 ALS/FTD iPSC-MG equally express microglial specific genes and perform microglial functions, including inflammatory cytokine release and phagocytosis of extracellular cargos, such as synthetic amyloid beta peptides and healthy human brain synaptoneurosomes. RNA sequencing analysis revealed select transcriptional changes of genes associated with neuroinflammation or neurodegeneration in diseased microglia yet no significant differentially expressed microglial-enriched genes. Moderate molecular and functional differences were observed in C9orf72 iPSC-MG mono-cultures despite the presence of C9orf72 pathological features suggesting that a diseased microenvironment may be required to induce phenotypic changes in microglial cells and the associated neuronal dysfunction seen in C9orf72 ALS/FTD neurodegeneration.
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Gap junction formation depends on the proper transport of connexin hemichannels to sites of cell-cell contact. Recently in Cell, Shaw et al. implicate microtubule tip tracking proteins in the trafficking of connexin43 to adherens junctions (Shaw et al., 2007). This finding suggests a mechanism for targeted delivery of membrane proteins by microtubule capture at the cortex.
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Junções Aderentes/metabolismo , Junções Comunicantes/metabolismo , Junções Intercelulares/metabolismo , Microtúbulos/metabolismo , Junções Aderentes/ultraestrutura , Animais , Moléculas de Adesão Celular/metabolismo , Comunicação Celular/fisiologia , Conexinas/metabolismo , Junções Comunicantes/ultraestrutura , Humanos , Junções Intercelulares/ultraestrutura , Microtúbulos/ultraestrutura , Proteínas Motores Moleculares/metabolismo , Transporte Proteico/fisiologiaRESUMO
The microtubule motor cytoplasmic dynein and its activator dynactin drive vesicular transport and mitotic spindle organization. Dynactin is ubiquitously expressed in eukaryotes, but a G59S mutation in the p150Glued subunit of dynactin results in the specific degeneration of motor neurons. This mutation in the conserved cytoskeleton-associated protein, glycine-rich (CAP-Gly) domain lowers the affinity of p150Glued for microtubules and EB1. Cell lines from patients are morphologically normal but show delayed recovery after nocodazole treatment, consistent with a subtle disruption of dynein/dynactin function. The G59S mutation disrupts the folding of the CAP-Gly domain, resulting in aggregation of the p150Glued protein both in vitro and in vivo, which is accompanied by an increase in cell death in a motor neuron cell line. Overexpression of the chaperone Hsp70 inhibits aggregate formation and prevents cell death. These data support a model in which a point mutation in p150Glued causes both loss of dynein/dynactin function and gain of toxic function, which together lead to motor neuron cell death.
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Transtornos Heredodegenerativos do Sistema Nervoso/genética , Transtornos Heredodegenerativos do Sistema Nervoso/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/fisiologia , Neurônios Motores/metabolismo , Animais , Apoptose/genética , Células COS , Células Cultivadas , Chlorocebus aethiops , Complexo Dinactina , Dineínas/metabolismo , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico HSP70/genética , Humanos , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/química , Microtúbulos/genética , Microtúbulos/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mutação PuntualRESUMO
The Hospital for Sick Children (SickKids) is situated in one of the most diverse cities in the world. This is reflected in the patient population it serves. In 2009, the hospital embarked on a quality improvement initiative to address the existing evidence base on health disparities and to enhance health equity through cultural competence programming. The goal was to achieve optimal health outcomes for all patients and families, with a particular focus on new immigrant and other vulnerable populations. Evaluation results indicate changes in clinical practice as a result of this initiative and increased patient satisfaction with regard to staff members' level of cultural sensitivity. This article provides an overview of this hospital-wide initiative, as well as the evaluation methods and outcomes. Based on a needs assessment, we developed an institutionally meaningful curriculum with SickKids' values of family-centred care, patient safety and service excellence embedded in the program. Educational sessions were delivered to clinical and non-clinical hospital staff, focusing on health disparities, the case for culturally competent care and practical tools for healthcare practitioners. Organizational change strategies, including the use of champions as change agents and role models, were used to embed cultural competence as integral to family-centred care at SickKids.
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Competência Cultural , Acessibilidade aos Serviços de Saúde , Qualidade da Assistência à Saúde , Hospitais Pediátricos , Humanos , Corpo Clínico Hospitalar , Ontário , Satisfação do PacienteRESUMO
Florid reactive periostitis ossificans (FRPO) is a benign juxta-cortical lesion of unknown etiology which most commonly occurs in the hands and feet. We report the radiographic, CT, and MR features of a pathologically confirmed FRPO in the distal femur, a location in which only a handful of cases has been reported. A 26-year-old male who presented with distal thigh pain initially underwent radiograph and CT, which illustrated a well-circumscribed, ossified lesion associated with the cortex of the femur without contiguity with the medullary canal. A subsequent MRI demonstrated heterogeneous signal intensity corresponding to the ossified portion of the lesion with a T2 hyperintense cartilaginous cap and surrounding edema. The lesion was surgically excised and pathologic diagnosis of FRPO, a mixture of osteoid, mature bone, cartilage and fibrous tissue, with associated inflammatory cells, was confirmed. Follow up four months after surgery revealed significant improvement in the patient's pain.
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Previous investigations on proteasomal preparations containing insulin-degrading enzyme (IDE; EC 3.4.24.56) have invariably yielded a co-purifying protein with a molecular weight of about 110kDa. We have now found both in MCF-7 breast cancer and HepG2 hepatoma cells that this associated molecule is the retinoblastoma tumor suppressor protein (RB). Interestingly, the amount of RB in this protein complex seemed to be lower in HepG2 vs. MCF-7 cells, indicating a higher (cytoplasmic) protein turnover in the former vs. the latter cells. Moreover, immunofluorescence showed increased nuclear localization of RB in HepG2 vs. MCF-7 cells. Beyond these subtle differences between these distinct tumor cell types, our present study more generally suggests an interplay between RB and IDE within the proteasome that may have important growth-regulatory consequences.
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Proliferação de Células , Insulisina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína do Retinoblastoma/metabolismo , Linhagem Celular Tumoral , Imunofluorescência , Humanos , Insulisina/isolamento & purificação , Proteína do Retinoblastoma/isolamento & purificaçãoRESUMO
Subjects with the metabolic syndrome (insulin resistance, glucose intolerance, dyslipidemia, hypertension, etc.) have a relative increase in abdominal fat tissue compared to normal individuals and obesity has also been shown to be associated with a decrease in insulin clearance. The majority of the clearance of insulin is due to the action of insulin-degrading enzyme (IDE) and IDE is present throughout all tissues. Since abdominal fat is increased in obesity we hypothesized that IDE may be altered in the different fat depots. Adipocytes were isolated from fat samples obtained from subjects during elective abdominal surgery. Fat samples were taken from subcutaneous (SQ) and visceral (VIS) sites. Insulin metabolism was compared in adipocytes isolated from SQ and VIS fat tissue. Adipocytes from the VIS site degraded more insulin that those from SQ fat tissue. Inhibitors of cathepsins B and D has no effect on the degradation of insulin, while bacitracin, an inhibitor of IDE, inhibited degradation by approx. 33% in both SQ and VIS adipocytes. These data show that insulin metabolism is relatively greater in VIS than in SQ fat tissue and potentially due to IDE.
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Gordura Abdominal/metabolismo , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Insulina/metabolismo , Tela Subcutânea/metabolismo , Gordura Abdominal/citologia , Tecido Adiposo/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Catepsina B/antagonistas & inibidores , Catepsina B/metabolismo , Catepsina D/antagonistas & inibidores , Catepsina D/metabolismo , Feminino , Humanos , Insulisina/antagonistas & inibidores , Insulisina/metabolismo , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The aim of this study was to evaluate whether a call triage assistant, who answered telephone calls to the main reading room during the busiest hours of weekend call, would impact resident workflow efficiency, diagnostic errors, and stress level. METHODS: The call triage assistant answered all telephone calls to the main reading room from 12 pm to 7 pm on 6 weekend days over a 3-month period. We compared report turnaround times and resident discrepancy rates on these days with control days, when the same residents were on call without the assistant. We also surveyed residents to determine whether the assistants relieved anxiety associated with the call shift. RESULTS: We recorded 168 telephone calls over the study period. We found the majority of telephone calls could be handled by the assistant without disturbing the on-call resident, resulting in a 71% reduction in interruptions. The mean turnaround time for studies read on the days the assistant was on duty was 44.3 min, compared with 75.2 min on the control days (P < .01). Resident major discrepancy rates (0.4% on the intervention days compared to 0.2% on the control days) were similar (P = .58), as were minor discrepancy rates (7.5% on the intervention days compared with 6.7% on the control days; P = .61). Residents reported fewer distractions, improved workflow efficiency, and decreased call-related stress when the assistant was on duty. CONCLUSIONS: A call triage assistant effectively improved workflow efficiency and reduced resident stress on call. Resident error rates were unaffected by the presence of the assistant.
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Internato e Residência , Triagem , Erros de Diagnóstico , Eficiência , Humanos , Inquéritos e Questionários , Fluxo de TrabalhoRESUMO
Women in sub-Saharan Africa are increasingly learning their HIV status in prevention of mother-to-child transmission of HIV (PMTCT) programmes in the context of antenatal care. This paper examines women's decisions about HIV testing and their experience of PMTCT and HIV-related care in one clinic in Lilongwe, Malawi. It is based on qualitative, ethnographic research conducted in 2004 and 2005, including interviews and focus group discussions with 55 HIV-positive women participating in a PMTCT programme, and 21 interviews with key informants from the programme and the health system. Women's expectations from testing were consistent with the benefits for their own health and their infants' health, as communicated by nurses. However, the PMTCT programme only poorly met their expectations. Reasons for this disjuncture included the construction of women as still healthy even when they needed treatment, a focus only on infant health, health system weaknesses, lack of integrated care and timely referral, and defining HIV exclusively as a medical issue, while ignoring the social determinants of health. Women's own health was particularly marginalised within the PMTCT programme, yet good models exist for comprehensive care for women, infants and their families that should be implemented as testing is scaled up.
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Sorodiagnóstico da AIDS , Infecções por HIV/tratamento farmacológico , Satisfação do Paciente , Diagnóstico Pré-Natal , Atenção à Saúde , Feminino , Grupos Focais , Acessibilidade aos Serviços de Saúde , Humanos , Entrevistas como Assunto , Malaui , Programas de RastreamentoRESUMO
OBJECTIVE: To determine the clinical, radiographic, and endoscopic findings of sleeve stenosis after sleeve gastrectomy and to correlate treatment with outcomes. METHODS: We identified 43 patients who underwent barium studies to evaluate upper GI symptoms after laparoscopic sleeve gastrectomy. The clinical, radiographic, and endoscopic findings were reviewed and correlated with treatment and outcomes. RESULTS: 26 patients (60%) had sleeve stenoses. All stenoses appeared as short segments of smooth, tapered narrowing, with a mean length of 8.0 mm and mean width of 7.5 mm, and 24 (92%) were located in the proximal or distal third of the sleeve. 23 patients (88%) had upstream dilation, and 1 (4%) had retained food proximal to the stenosis. 23 (70%) of 33 patients with obstructive symptoms and 3 (30%) of 10 without obstructive symptoms had sleeve stenoses. Endoscopy revealed sleeve stenosis in 8 (67%) of 12 patients with radiographic stenosis. Endoscopic dilation resulted in improvement/resolution of symptoms in seven (88%) of 8 patients. CONCLUSION: Sleeve stenosis after sleeve gastrectomy was characterized radiographically by a short segment of smooth, tapered narrowing, typically in the proximal or distal third of the sleeve. Approximately, 70% of patients with obstructive symptoms and 30% with non-obstructive symptoms had sleeve stenosis. One-third of radiographically diagnosed stenoses were not seen at endoscopy. The barium study, therefore, is a useful test for sleeve stenosis in patients with obstructive or nonobstructive symptoms after sleeve gastrectomy. Advances in knowledge: This article describes the appearance and location of sleeve stenoses after laparoscopic sleeve gastrectomy and the clinical presentation and treatment options for these patients.
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Gastrectomia/efeitos adversos , Coto Gástrico/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Adolescente , Adulto , Idoso , Radioisótopos de Bário , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/etiologia , Feminino , Gastrectomia/métodos , Coto Gástrico/patologia , Gastroscopia , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Estômago/cirurgia , Adulto JovemRESUMO
OBJECTIVE: Assess the consumer nutrition environment in midsize to large supermarkets by supermarket type and area-level socioeconomic variables. DESIGN: Cross-sectional census of 257 supermarkets using the Toronto Nutrition Environment Measures Survey in Stores. SETTING: Toronto, Canada. VARIABLES MEASURED: Availability; price and linear shelf space of fruits and vegetables vs energy-dense snack foods by supermarket type; after-tax, low-income measure; and neighborhood improvement area. ANALYSIS: Multivariate linear regression. RESULTS: There was a high availability of fruits (7.7 of 8) and vegetables (9.5 of 11). There was similar linear shelf space for fruits and vegetables vs energy-dense snack foods (ratio, 1.1 m). Adjusted fruit prices were lowest in quintiles 1 (ß = -$1.30; P = .008), 2 (ß = -$1.41; P = .005), and 3 (ß = -$1.89; P < .001) vs quintile 5 (lowest percentage of people living with low income) and in ethnic (ß = -$3.47; P < .001) and discount stores (ß = -$5.64; P < .001) vs conventional. Adjusted vegetable prices were lowest in quintiles 2 (ß = -$1.87; P = .04), 3 (ß = -$1.78; P = .03), and 4 (ß = -$2.65; P = .001) vs quintile 5 and in ethnic (ß = -$7.10; P < .001) and discount (ß = -$5.49; P < .001) stores. They were highest in other (ß = + $3.08; P = .003) vs conventional stores. Adjusted soda and chips prices were lower in discount (ß = -$1.16; P < .001) and higher in other stores (ß = + $0.67; P < .001) vs conventional. CONCLUSIONS AND IMPLICATIONS: Findings do not indicate inequities in shelf space, availability, or price across diverse neighborhoods. Practitioners can use findings to help consumers navigate supermarkets to make healthy choices.
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Abastecimento de Alimentos , Alimentos/estatística & dados numéricos , Características de Residência , Censos , Comércio/estatística & dados numéricos , Estudos Transversais , Abastecimento de Alimentos/estatística & dados numéricos , Humanos , Modelos Lineares , Ontário , Características de Residência/estatística & dados numéricos , Fatores SocioeconômicosRESUMO
Proteins are vital to the overall structure of cells and to the function of cells in the form of enzymes. Thus the control of protein metabolism is among the most important aspects of cellular metabolism. Insulin's major effect on protein metabolism in the adult animal is inhibition of protein degradation. This is via inhibition of proteasome activity via an interaction with insulin-degrading enzyme (IDE). IDE is responsible for the majority of cellular insulin degradation. We hypothesized that a reduction in IDE would reduce insulin degradation and insulin's ability to inhibit protein degradation. HepG2 cells were transfected with siRNA against human IDE and insulin degradation and protein degradation measured. Both IDE mRNA and protein were reduced by >50% in the IDE siRNA transfected cells. Insulin degradation was reduced by approximately 50%. Cells were labeled with [3H]-leucine to investigate protein degradation. Short-lived protein degradation was unchanged in the cells with reduced IDE expression. Long-lived and very-long-lived protein degradation was reduced in the cells with reduced IDE expression (14.0+/-0.16 vs. 12.5+/-0.07%/4h (long-lived), 9.6+/-2.2% vs. 7.3+/-0.2%/3h (very-long-lived), control vs. IDE transfected, respectively, P<0.005). The inhibition of protein degradation by insulin was reduced 37-76% by a decreased expression of IDE in HepG2 cells. This shows that IDE is involved in cellular insulin metabolism and provides further evidence that insulin inhibits protein degradation via an interaction with IDE.
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Carcinoma Hepatocelular/metabolismo , Inativação Gênica/fisiologia , Insulina/metabolismo , Insulisina/metabolismo , RNA Interferente Pequeno/genética , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica , HumanosRESUMO
STUDY OBJECTIVES: Sleep disruption is increasingly recognized in hospitalized patients. Impaired sleep is associated with measureable alterations in neurodevelopment. The neonatal intensive care unit (NICU) environment has the potential to affect sleep quality and quantity. We aimed: (i) to determine the frequency and duration of hands-on care, and its impact on sleep, for NICU patients; and (ii) to assess the incidence of respiratory events associated with handling for a cohort of sick neonates. METHODS: Term and near-term neonates admitted to the NICU and at risk for cerebral dysfunction due to severity of illness or clinical suspicion for seizures underwent attended, bedside polysomnography. Continuous polysomnogram segments were analyzed and data on handling, infant behavioral state, and associated respiratory events were recorded. RESULTS: Video and polysomnography data were evaluated for 25 infants (gestational age 39.4 ± 1.6 weeks). The maximum duration between handling episodes for each infant was 50.9 ± 26.2 min, with a median of 2.3 min between contacts. Handling occurred across all behavioral states (active sleep 29.5%; quiet sleep 23.1%; awake 29.9%; indeterminate 17.4%; P = 0.99). Arousals or awakenings occurred in 57% of contacts with a sleeping infant. Hypopnea, apnea, and oxygen desaturation occurred with 16%, 8%, and 19.5% of contacts, respectively. Hypopnea was most likely to occur following contact with infants in active sleep (28%; P < 0.001). CONCLUSIONS: Infants in the NICU experience frequent hands-on care, associated with disturbances of sleep and respiration. The potential health and developmental impact of these disturbances merits study, as strategies to monitor sleep and minimize sleep-disordered breathing might then improve NICU outcomes. Pediatr Pulmonol. 2017;52:84-90 © 2016 Wiley Periodicals, Inc.
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Unidades de Terapia Intensiva Neonatal , Polissonografia , Respiração , Síndromes da Apneia do Sono/terapia , Sono/fisiologia , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Síndromes da Apneia do Sono/fisiopatologiaRESUMO
BACKGROUND: Limb-girdle muscular dystrophies (LGMDs) are a heterogeneous group of inherited autosomal myopathies that preferentially affect voluntary muscles of the shoulders and hips. LGMD has been clinically described in several breeds of dogs, but the responsible mutations are unknown. The clinical presentation in dogs is characterized by marked muscle weakness and atrophy in the shoulder and hips during puppyhood. METHODS: Following clinical evaluation, the identification of the dystrophic histological phenotype on muscle histology, and demonstration of the absence of sarcoglycan-sarcospan complex by immunostaining, whole exome sequencing was performed on five Boston terriers: one affected dog and its three family members and one unrelated affected dog. RESULTS: Within sarcoglycan-δ (SGCD), a two base pair deletion segregating with LGMD in the family was discovered, and a deletion encompassing exons 7 and 8 was found in the unrelated dog. Both mutations are predicted to cause an absence of SGCD protein, confirmed by immunohistochemistry. The mutations are private to each family. CONCLUSIONS: Here, we describe the first cases of canine LGMD characterized at the molecular level with the classification of LGMD2F.