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1.
Hepatology ; 74(1): 281-295, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33226645

RESUMO

BACKGROUND AND AIMS: Altered bile acid (BA) homeostasis is an intrinsic facet of cholestatic liver diseases, but clinical usefulness of plasma BA assessment in primary sclerosing cholangitis (PSC) remains understudied. We performed BA profiling in a large retrospective cohort of patients with PSC and matched healthy controls, hypothesizing that plasma BA profiles vary among patients and have clinical utility. APPROACH AND RESULTS: Plasma BA profiling was performed in the Clinical Biochemical Genetics Laboratory at Mayo Clinic using a mass spectrometry based assay. Cox proportional hazard (univariate) and gradient boosting machines (multivariable) models were used to evaluate whether BA variables predict 5-year risk of hepatic decompensation (HD; defined as ascites, variceal hemorrhage, or encephalopathy). There were 400 patients with PSC and 302 controls in the derivation cohort (Mayo Clinic) and 108 patients with PSC in the validation cohort (Norwegian PSC Research Center). Patients with PSC had increased BA levels, conjugated fraction, and primary-to-secondary BA ratios relative to controls. Ursodeoxycholic acid (UDCA) increased total plasma BA level while lowering cholic acid and chenodeoxycholic acid concentrations. Patients without inflammatory bowel disease (IBD) had primary-to-secondary BA ratios between those of controls and patients with ulcerative colitis. HD risk was associated with increased concentration and conjugated fraction of many BA, whereas higher G:T conjugation ratios were protective. The machine-learning model, PSC-BA profile score (concordance statistic [C-statistic], 0.95), predicted HD better than individual measures, including alkaline phosphatase, and performed well in validation (C-statistic, 0.86). CONCLUSIONS: Patients with PSC demonstrated alterations of plasma BA consistent with known mechanisms of cholestasis, UDCA treatment, and IBD. Notably, BA profiles predicted future HD, establishing the clinical potential of BA profiling, which may be suited for use in clinical trials.


Assuntos
Ascite/epidemiologia , Ácidos e Sais Biliares/sangue , Colangite Esclerosante/complicações , Varizes Esofágicas e Gástricas/epidemiologia , Encefalopatia Hepática/epidemiologia , Adulto , Idoso , Ascite/etiologia , Estudos de Casos e Controles , Colangite Esclerosante/sangue , Colangite Esclerosante/fisiopatologia , Varizes Esofágicas e Gástricas/etiologia , Estudos de Viabilidade , Feminino , Voluntários Saudáveis , Encefalopatia Hepática/etiologia , Humanos , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco/métodos
2.
Am J Hum Genet ; 103(4): 553-567, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30290151

RESUMO

The conserved oligomeric Golgi (COG) complex is involved in intracellular vesicular transport, and is composed of eight subunits distributed in two lobes, lobe A (COG1-4) and lobe B (COG5-8). We describe fourteen individuals with Saul-Wilson syndrome, a rare form of primordial dwarfism with characteristic facial and radiographic features. All affected subjects harbored heterozygous de novo variants in COG4, giving rise to the same recurrent amino acid substitution (p.Gly516Arg). Affected individuals' fibroblasts, whose COG4 mRNA and protein were not decreased, exhibited delayed anterograde vesicular trafficking from the ER to the Golgi and accelerated retrograde vesicular recycling from the Golgi to the ER. This altered steady-state equilibrium led to a decrease in Golgi volume, as well as morphologic abnormalities with collapse of the Golgi stacks. Despite these abnormalities of the Golgi apparatus, protein glycosylation in sera and fibroblasts from affected subjects was not notably altered, but decorin, a proteoglycan secreted into the extracellular matrix, showed altered Golgi-dependent glycosylation. In summary, we define a specific heterozygous COG4 substitution as the molecular basis of Saul-Wilson syndrome, a rare skeletal dysplasia distinct from biallelic COG4-CDG.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Transporte Proteico/genética , Proteoglicanas/genética , Proteínas de Transporte Vesicular/genética , Adulto , Substituição de Aminoácidos/genética , Animais , Animais Geneticamente Modificados/genética , Linhagem Celular , Criança , Pré-Escolar , Retículo Endoplasmático/genética , Matriz Extracelular/genética , Feminino , Fibroblastos/patologia , Glicosilação , Complexo de Golgi/genética , Heterozigoto , Humanos , Lactente , Masculino , Peixe-Zebra
3.
Am J Med Genet A ; 185(1): 213-218, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33044030

RESUMO

Glycosylation is a critical post/peri-translational modification required for the appropriate development and function of the immune system. As an example, abnormalities in glycosylation can cause antibody deficiency and reduced lymphocyte signaling, although the phenotype can be complex given the diverse roles of glycosylation. Human MGAT2 encodes N-acetylglucosaminyltransferase II, which is a critical enzyme in the processing of oligomannose to complex N-glycans. Complex N-glycans are essential for immune system functionality, but only one individual with MGAT2-CDG has been described to have an abnormal immunologic evaluation. MGAT2-CDG (CDG-IIa) is a congenital disorder of glycosylation (CDG) associated with profound global developmental disability, hypotonia, early onset epilepsy, and other multisystem manifestations. Here, we report a 4-year old female with MGAT2-CDG due to a novel homozygous pathogenic variant in MGAT2, a 4-base pair deletion, c.1006_1009delGACA. In addition to clinical features previously described in MGAT2-CDG, she experienced episodic asystole, persistent hypogammaglobulinemia, and defective ex vivo mitogen and antigen proliferative responses, but intact specific vaccine antibody titers. Her infection history has been mild despite the testing abnormalities. We compare this patient to the 15 previously reported patients in the literature, thus expanding both the genotypic and phenotypic spectrum for MGAT2-CDG.


Assuntos
Arritmias Cardíacas/genética , Defeitos Congênitos da Glicosilação/genética , Doenças do Sistema Imunitário/genética , N-Acetilglucosaminiltransferases/genética , Arritmias Cardíacas/complicações , Arritmias Cardíacas/imunologia , Arritmias Cardíacas/patologia , Pré-Escolar , Defeitos Congênitos da Glicosilação/complicações , Defeitos Congênitos da Glicosilação/imunologia , Defeitos Congênitos da Glicosilação/patologia , Feminino , Glicosilação , Homozigoto , Humanos , Doenças do Sistema Imunitário/complicações , Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/patologia , Mutação/genética , N-Acetilglucosaminiltransferases/imunologia , Fenótipo
4.
BJOG ; 128(6): 984-993, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33012050

RESUMO

OBJECTIVE: To estimate prevalence of vaping in pregnancy. Compare characteristics and attitudes between exclusive smokers and vapers, and between exclusive vapers and dual users (smoke and vape). DESIGN: Cross-sectional survey. SETTING: Hospitals across England and Scotland. POPULATION: Pregnant women attending antenatal clinics in 2017. METHODS: Women at 8-24 weeks' gestation completed screening questions about their smoking and vaping. Current or recent ex-smokers and/or vapers completed a full detailed survey about vaping and smoking. MAIN OUTCOME MEASURES: The prevalence of vaping, characteristics and attitudes of women who vape and/or smoke. RESULTS: Of 3360 pregnant women who completed screening questions, 515 (15.3%, 95% CI 14.1-16.6) were exclusive smokers, 44 (1.3%, 95% CI 1.0-1.8) exclusive vapers and 118 (3.5%, 95% CI 2.9-4.2) dual users. In total, 867 (25.8%) women completed the full survey; compared with smokers (n = 434), vapers (n = 140) were more likely to hold higher educational qualifications (odds ratio [OR) 1.51, 95% CI 1.01-2.25). Compared with exclusive vapers (n = 33), dual users (n = 107) were younger (OR 0.91 95% CI 0.85-0.98) and less likely to hold high qualifications (OR 0.43, 95% CI 0.20-0.96). Compared with smokers, dual users were more likely to be planning to quit smoking (OR 2.27, 95% CI 1.24-4.18). Compared with smokers, vapers were more likely to think vaping was safer than smoking (78.6% versus 36.4%). CONCLUSIONS: One in 20 pregnant women report vaping, and most also smoke. Dual users are more motivated towards stopping smoking than smokers. Where women have tried but cannot stop smoking, clinicians could encourage them to consider vaping for smoking cessation. TWEETABLE EXTRACT: One in 20 women report vaping during pregnancy but of those that do vape, most also smoke, despite having intentions to quit.


Assuntos
Fumar Cigarros , Gestantes/psicologia , Abandono do Hábito de Fumar/psicologia , Vaping , Adulto , Atitude Frente a Saúde , Fumar Cigarros/epidemiologia , Fumar Cigarros/psicologia , Estudos Transversais , Cultura , Escolaridade , Inglaterra/epidemiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Intenção , Motivação , Gravidez , Escócia/epidemiologia , Vaping/epidemiologia , Vaping/psicologia
5.
Genet Med ; 22(6): 1108-1118, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32089546

RESUMO

PURPOSE: Newborn screening (NBS) for Krabbe disease (KD) is performed by measurement of galactocerebrosidase (GALC) activity as the primary test. This revealed that GALC activity has poor specificity for KD. Psychosine (PSY) was proposed as a disease marker useful to reduce the false positive rate for NBS and for disease monitoring. We report a highly sensitive PSY assay that allows identification of KD patients with minimal PSY elevations. METHODS: PSY was extracted from dried blood spots or erythrocytes with methanol containing d5-PSY as internal standard, and measured by liquid chromatography-tandem mass spectrometry. RESULTS: Analysis of PSY in samples from controls (N = 209), GALC pseudodeficiency carriers (N = 55), GALC pathogenic variant carriers (N = 27), patients with infantile KD (N = 26), and patients with late-onset KD (N = 11) allowed for the development of an effective laboratory screening and diagnostic algorithm. Additional longitudinal measurements were used to track therapeutic efficacy of hematopoietic stem cell transplantion (HSCT). CONCLUSION: This study supports PSY quantitation as a critical component of NBS for KD. It helps to differentiate infantile from later onset KD variants, as well as from GALC variant and pseudodeficiency carriers. Additionally, this study provides further data that PSY measurement can be useful to monitor KD progression before and after treatment.


Assuntos
Leucodistrofia de Células Globoides , Psicosina , Teste em Amostras de Sangue Seco , Galactosilceramidase/genética , Humanos , Recém-Nascido , Leucodistrofia de Células Globoides/diagnóstico , Leucodistrofia de Células Globoides/genética , Triagem Neonatal
6.
Genet Med ; 20(8): 847-854, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29120458

RESUMO

PURPOSE: The implementation of newborn screening for lysosomal disorders has uncovered overall poor specificity, psychosocial harm experienced by caregivers, and costly follow-up testing of false-positive cases. We report an informatics solution proven to minimize these issues. METHODS: The Kentucky Department for Public Health outsourced testing for mucopolysaccharidosis type I (MPS I) and Pompe disease, conditions recently added to the recommended uniform screening panel, plus Krabbe disease, which was added by legislative mandate. A total of 55,161 specimens were collected from infants born over 1 year starting from February 2016. Testing by tandem mass spectrometry was integrated with multivariate pattern recognition software (Collaborative Laboratory Integrated Reports), which is freely available to newborn screening programs for selection of cases for which a biochemical second-tier test is needed. RESULTS: Of five presumptive positive cases, one was affected with infantile Krabbe disease, two with Pompe disease, and one with MPS I. The remaining case was a heterozygote for the latter condition. The false-positive rate was 0.0018% and the positive predictive value was 80%. CONCLUSION: Postanalytical interpretive tools can drastically reduce false-positive outcomes, with preliminary evidence of no greater risk of false-negative events, still to be verified by long-term surveillance.


Assuntos
Doenças por Armazenamento dos Lisossomos/diagnóstico , Triagem Neonatal/métodos , Teste em Amostras de Sangue Seco , Feminino , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Humanos , Lactente , Recém-Nascido , Leucodistrofia de Células Globoides/diagnóstico , Masculino , Mucopolissacaridose I/diagnóstico , Reconhecimento Automatizado de Padrão , Sensibilidade e Especificidade , Software , Espectrometria de Massas em Tandem/métodos
7.
J Helminthol ; 94: e9, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30428945

RESUMO

Phasmarhabditis hermaphrodita is a parasitic nematode of terrestrial gastropods that has been formulated into a biological control agent for farmers and gardeners to kill slugs and snails. In order to locate slugs it is attracted to mucus, faeces and volatile cues; however, there is no information about whether these nematodes are attracted to snail cues. It is also unknown how wild isolates of P. hermaphrodita or different Phasmarhabditis species behave when exposed to gastropod cues. Therefore, we investigated whether P. hermaphrodita (commercial and wild isolated strains), P. neopapillosa and P. californica were attracted to mucus from several common snail species (Cepaea nemoralis, Cepaea hortensis, Arianta arbustorum and Cornu aspersum). We also examined whether snails (C. aspersum) collected from different locations around the UK differed in their attractiveness to wild isolates of P. hermaphrodita. Furthermore, we also investigated what properties of snail mucus the nematodes were attracted to, including hyaluronic acid and metal salts (FeSO4, ZnSO4, CuSO4 and MgSO4). We found that the commercial strain of P. hermaphrodita responded poorly to snail mucus compared to wild isolated strains, and C. aspersum collected from different parts of the UK differed in their attractiveness to the nematodes. We found that Phasmarhabditis nematodes were weakly attracted to all metals tested but were strongly attracted to hyaluronic acid. In a final experiment we also showed that pharmacological manipulation of cyclic guanosine monophosphate (cGMP) increased chemoattraction to snail mucus, suggesting that the protein kinase EGL-4 may be responsible for Phasmarhabditis sp. chemoattraction.


Assuntos
GMP Cíclico/metabolismo , Gastrópodes/parasitologia , Ácido Hialurônico/metabolismo , Rhabditoidea/fisiologia , Animais , Fezes/parasitologia , Gastrópodes/metabolismo , Muco/metabolismo , Muco/parasitologia , Rhabditoidea/genética , Rhabditoidea/isolamento & purificação , Transdução de Sinais
8.
Mol Psychiatry ; 21(12): 1663-1671, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27698429

RESUMO

Autism spectrum disorder (ASD) occurs in 1 in 68 births, preferentially affecting males. It encompasses a group of neurodevelopmental abnormalities characterized by impaired social interaction and communication, stereotypic behaviors and motor dysfunction. Although recent advances implicate maternal brain-reactive antibodies in a causative role in ASD, a definitive assessment of their pathogenic potential requires cloning of such antibodies. Here, we describe the isolation and characterization of monoclonal brain-reactive antibodies from blood of women with brain-reactive serology and a child with ASD. We further demonstrate that male but not female mice exposed in utero to the C6 monoclonal antibody, binding to contactin-associated protein-like 2 (Caspr2), display abnormal cortical development, decreased dendritic complexity of excitatory neurons and reduced numbers of inhibitory neurons in the hippocampus, as well as impairments in sociability, flexible learning and repetitive behavior. Anti-Caspr2 antibodies are frequent in women with brain-reactive serology and a child with ASD. Together these studies provide a methodology for obtaining monclonal brain-reactive antibodies from blood B cells, demonstrate that ASD can result from in utero exposure to maternal brain-reactive antibodies of single specificity and point toward the exciting possibility of prognostic and protective strategies.


Assuntos
Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Adulto , Animais , Anticorpos/sangue , Anticorpos/metabolismo , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Encéfalo/metabolismo , Complemento C6 , Feminino , Hipocampo/metabolismo , Humanos , Aprendizagem , Troca Materno-Fetal , Proteínas de Membrana/sangue , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mães , Proteínas do Tecido Nervoso/sangue , Neurônios/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Fatores Sexuais , Comportamento Social
9.
BMC Health Serv Res ; 17(1): 545, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28789643

RESUMO

BACKGROUND: The UK National Health Service provides Stop Smoking Services for pregnant women (SSSP) but there is a lack of evidence concerning how these are best organised. This study investigates influences on services' effectiveness and also on their propensity to engage pregnant smokers with support in stopping smoking. METHODS: Survey data collected from 121/141 (86%) of SSSP were augmented with data from Hospital Episode Statistics and the 2011 UK National Census. 'Reach' or propensity to engage smokers with support was defined as the percentage of pregnant smokers setting a quit date with SSSP support, and 'Effectiveness' as the percentage of women who set a quit date who also reported abstinence at four weeks later. A bivariate (i.e. two outcome variable) response Markov Chain Monte Carlo model was used to identify service-level factors associated with the Reach and Effectiveness of SSSP. RESULTS: Beta coefficients represent a percentage change in Reach and Effectiveness by the covariate. Providing the majority of one-to-one contacts in a clinic rather than at home increased both Reach (%) (ß: 6.97, 95% CI: 3.34, 10.60) and Effectiveness (%) (ß: 7.37, 95% CI: 3.03, 11.70). Reach of SSSP was also increased when the population served was more deprived (ß for increase in Reach with a one unit increase in IMD score: 0.55, 95% CI: 0.25, 0.85), had a lower proportion of people with dependent children (ß: -2.52, 95% CI: -3.82, -1.22), and a lower proportion of people in managerial or professional occupations (ß: -0.31, 95% CI: -0.59, -0.03). The Effectiveness of SSSP was decreased in those areas that had a greater percentage of people >16 years with no educational qualifications (ß: -0.51, 95% CI: -0.95, -0.07). CONCLUSIONS: To engage pregnant smokers and to encourage them to quit, it may be more efficient for SSSP support to be focussed around clinics, rather than women's homes. Reach of SSSP is inversely associated with disadvantage and efforts should be made to contact these women as they are less likely to achieve abstinence in the short and longer term.


Assuntos
Abandono do Hábito de Fumar , Prevenção do Hábito de Fumar , Adolescente , Adulto , Fumar Cigarros , Feminino , Humanos , Gravidez , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/estatística & dados numéricos , Inquéritos e Questionários , Resultado do Tratamento , Reino Unido , Adulto Jovem
10.
Clin Chem ; 62(9): 1248-54, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27440509

RESUMO

BACKGROUND: Newborn screening for lysosomal storage disorders (LSD) has revealed that late-onset variants of these conditions are unexpectedly frequent and therefore may evade diagnosis. We developed an efficient and cost-effective multiplex assay to diagnose six LSDs and several peroxisomal disorders in patients presenting with diverse phenotypes at any age. METHODS: Three 3-mm dried blood spot (DBS) punches were placed into individual microtiter plates. One disc was treated with a cocktail containing acid sphingomyelinase-specific substrate and internal standard (IS). To the second DBS we added a cocktail containing substrate and IS for ß-glucosidase, acid α-glucosidase, α-galactosidase A, galactocerebrosidase, and α-L-iduronidase. The third DBS was extracted with methanol containing d4-C26 lysophosphatidylcholine as IS and stored until the enzyme plates were combined and purified by liquid-liquid and solid-phase extraction. The extracts were evaporated, reconstituted with the extract from the lysophosphatidylcholine plate, and analyzed by flow injection tandem mass spectrometry. RESULTS: Reference intervals were determined by analysis of 550 samples from healthy controls. DBS from confirmed patients with 1 of the 6 LSDs (n = 33), X-adrenoleukodystrophy (n = 9), or a peroxisomal biogenesis disorder (n = 5), as well as carriers for Fabry disease (n = 17) and X-adrenoleukodystrophy (n = 5), were analyzed for assay validation. Prospective clinical testing of 578 samples revealed 25 patients affected with 1 of the detectable conditions. CONCLUSIONS: Our flow injection tandem mass spectrometry approach is amenable to high-throughput population screening for Hurler disease, Gaucher disease, Niemann-Pick A/B disease, Pompe disease, Krabbe disease, Fabry disease, X-adrenoleukodystrophy, and peroxisomal biogenesis disorder in DBS.


Assuntos
Adrenoleucodistrofia/sangue , Teste em Amostras de Sangue Seco , Doenças por Armazenamento dos Lisossomos/sangue , Adrenoleucodistrofia/diagnóstico , Humanos , Doenças por Armazenamento dos Lisossomos/diagnóstico , Espectrometria de Massas em Tandem
11.
Am J Physiol Regul Integr Comp Physiol ; 310(10): R960-7, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26936780

RESUMO

Obesity is a risk factor for cardiovascular disease and is associated with increased plasma levels of the adipose-derived hormone leptin. Vascular smooth muscle cells (VSMC) express leptin receptors (LepR); however, their physiological role is unclear. We hypothesized that leptin, at levels to mimic morbid obesity, impairs vascular relaxation. To test this, we used control and VSM-LepR knockout mice (VSM-LepR KO) created with a tamoxifen-inducible specific Cre recombinase to delete the LepR gene in VSMC. Control (10-12 wk old) and VSM-LepR KO (10-12 wk old) mice were fed a diet containing tamoxifen (50 mg/kg) for 6 wk, after which vascular reactivity was studied in isolated carotid arteries using an organ chamber bath. Vessels were incubated with leptin (100 ng/ml) or vehicle (0.1 mM Tris·HCl) for 30 min. Leptin treatment resulted in significant impairment of vessel relaxation to the endothelial-specific agonist acetylcholine (ACh). When these experiments were repeated in the presence of the superoxide scavenger tempol, relaxation responses to ACh were restored. VSM-LepR deletion resulted in a significant attenuation of leptin-mediated impaired ACh-induced relaxation. These data show that leptin directly impairs vascular relaxation via a VSM-LepR-mediated mechanism, suggesting a potential pathogenic role for leptin to increase cardiovascular risk during obesity.


Assuntos
Deleção de Genes , Leptina/farmacologia , Músculo Liso Vascular/metabolismo , Receptores para Leptina/metabolismo , Vasodilatação/fisiologia , Animais , Antagonistas de Estrogênios/farmacologia , Feminino , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Receptores para Leptina/genética , Tamoxifeno/farmacologia
12.
Mol Genet Metab ; 114(1): 46-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25481105

RESUMO

BACKGROUND: Pre-symptomatic hematopoietic stem cell transplantation is essential to achieve best possible outcomes for patients with the childhood cerebral form of X-linked adrenoleukodystrophy (X-ALD). We describe a high-throughput method for measurement of C20-C26 lysophosphatidylcholines (LPCs) and biochemical diagnosis of X-ALD using the same dried blood spots (DBS) routinely used for newborn screening. METHODS: LPCs are extracted from 3-mm DBS punch with methanol containing an isotopically labeled LPC as internal standard. This extract is transferred to a 96-well plate, evaporated and then reconstituted in mobile phase for flow injection analysis tandem mass spectrometry (FIA-MS/MS) in selected reaction monitoring mode for measurement of four different LPCs (C20, C22, C24, C26) and the internal standard (d4-C26-LPC). Analysis time is 1.5min per sample. RESULTS: The mean CVs from the intra- and inter-assay experiments for LPCs were 6.3-15.1% for C20-LPC, 4.4-18.6% for C22-LPC and 4.5-14.3% for C24-LPC. Limits of detection were determined for C20-LPC (LOD=0.03µg/mL), C22-LPC (0.03µg/mL), C24-LPC (0.03µg/mL) and C26-LPC (0.01µg/mL). Reference ranges were established from DBS of 130 newborns and 20 adults. Samples of patients with X-ALD (n=16), peroxisomal biogenesis disorders (n=8), and X-ALD carriers (n=12) were analyzed blindly and all were correctly identified. CONCLUSION: Analysis of LPC species by FIA-MS/MS is a fast, simple and reliable method to screen for X-ALD and other peroxisomal disorders in DBS. To maximize specificity, abnormal results can be verified by a 2nd tier assay using LC-MS/MS.


Assuntos
Adrenoleucodistrofia/sangue , Teste em Amostras de Sangue Seco , Lisofosfatidilcolinas/sangue , Triagem Neonatal/métodos , Adulto , Cromatografia Líquida , Ensaios de Triagem em Larga Escala , Humanos , Recém-Nascido , Limite de Detecção , Transtornos Peroxissômicos/sangue , Valores de Referência , Espectrometria de Massas em Tandem/métodos
13.
J Inherit Metab Dis ; 38(5): 923-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25762404

RESUMO

BACKGROUND: Newborn screening (NBS) for Krabbe disease (KD) in New York and Missouri is conducted by measuring galactocerebrosidase (GALC) activity using tandem mass spectrometry (MS/MS). These NBS efforts have shown that the incidence of KD is unexpectedly low (1:400,000) while many individuals (ca. 1:6000) with reduced GALC activity and genotypes of uncertain significance are detected and subjected to follow up testing. Psychosine (PSY) is a putative marker of KD progression and can be measured in dried blood spots (DBS). We sought to determine the role that PSY levels play in NBS for KD, follow up, and treatment monitoring. METHODS: PSY was eluted from DBS with methanol containing N,N-dimethyl-D-erythro-sphingosine as internal standard (IS). Liquid chromatography-MS/MS was conducted over 17 minutes in the multiple reaction monitoring positive mode to follow the precursor to product species transitions for PSY and IS. Separation of the structural isomers PSY and glucosylsphingosine was accomplished by hydrophilic interaction liquid chromatography. RESULTS: Pre-analytical and analytical factors were studied and revealed satisfactory results. PSY was also measured in DBS collected from controls (range: <8 nmol/L, N = 220), KD patients at various disease stages (range: 8-112, N = 26), and GALC mutation carriers (range: <15 nmol/L, N = 18). CONCLUSIONS: PSY measurement in DBS could serve as a 2nd tier assay in NBS for KD, simplify and reduce the cost of follow up protocols, help determine disease progression, and be used to monitor KD patients following hematopoietic stem cell transplantation. However, additional chronological measurements of PSY in KD patients are required to confirm these possibilities.


Assuntos
Teste em Amostras de Sangue Seco , Leucodistrofia de Células Globoides/diagnóstico , Triagem Neonatal/métodos , Psicosina/sangue , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Teste em Amostras de Sangue Seco/normas , Humanos , Lactente , Recém-Nascido , Leucodistrofia de Células Globoides/sangue , Limite de Detecção , Pessoa de Meia-Idade , Triagem Neonatal/normas , Psicosina/análise , Melhoria de Qualidade , Valores de Referência , Reprodutibilidade dos Testes , Adulto Jovem
14.
Genet Med ; 14(7): 648-55, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22766634

RESUMO

PURPOSE: To improve quality of newborn screening by tandem mass spectrometry with a novel approach made possible by the collaboration of 154 laboratories in 49 countries. METHODS: A database of 767,464 results from 12,721 cases affected with 60 conditions was used to build multivariate pattern recognition software that generates tools integrating multiple clinically significant results into a single score. This score is determined by the overlap between normal and disease ranges, penetration within the disease range, differences between conditions, and weighted correction factors. RESULTS: Ninety tools target either a single condition or the differential diagnosis between multiple conditions. Scores are expressed as the percentile rank among all cases with the same condition and are compared to interpretation guidelines. Retrospective evaluation of past cases suggests that these tools could have avoided at least half of 279 false-positive outcomes caused by carrier status for fatty-acid oxidation disorders and could have prevented 88% of known false-negative events. CONCLUSION: Application of this computational approach to raw data is independent from single analyte cutoff values. In Minnesota, the tools have been a major contributing factor to the sustained achievement of a false-positive rate below 0.1% and a positive predictive value above 60%.


Assuntos
Triagem Neonatal/métodos , Software , Espectrometria de Massas em Tandem/métodos , Biologia Computacional , Interpretação Estatística de Dados , Bases de Dados Factuais , Diagnóstico Diferencial , Reações Falso-Positivas , Humanos , Recém-Nascido , Cooperação Internacional , Metaboloma , Minnesota , Análise Multivariada , Reconhecimento Automatizado de Padrão , Valor Preditivo dos Testes , Estudos Retrospectivos
15.
Pilot Feasibility Stud ; 8(1): 231, 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273227

RESUMO

BACKGROUND: Antenatal pelvic floor muscle exercises (PFME) in women without prior urinary incontinence (UI) are effective in reducing postnatal UI; however, UK midwives often do not provide advice and information to women on undertaking PFME, with evidence that among women who do receive advice, many do not perform PFME. METHODS: The primary aim of this feasibility and pilot cluster randomised controlled trial is to provide a potential assessment of the feasibility of undertaking a future definitive trial of a midwifery-led antenatal intervention to support women to perform PFME in pregnancy and reduce UI postnatally. Community midwifery teams in participating NHS sites comprise trial clusters (n = 17). Midwives in teams randomised to the intervention will be trained on how to teach PFME to women and how to support them in undertaking PFME in pregnancy. Women whose community midwifery teams are allocated to control will receive standard antenatal care only. All pregnant women who give birth over a pre-selected sample month who receive antenatal care from participating community midwifery teams (clusters) will be sent a questionnaire at 10-12 weeks postpartum (around 1400-1500 women). Process evaluation data will include interviews with midwives to assess if the intervention could be implemented as planned. Interviews with women in both trial arms will explore their experiences of support from midwives to perform PFME during pregnancy. Data will be stored securely at the Universities of Birmingham and Exeter. Results will be disseminated through publications aimed at maternity service users, clinicians, and academics and inform a potential definitive trial of effectiveness. The West Midlands-Edgbaston Research Ethics Committee approved the study protocol. DISCUSSION: Trial outcomes will determine if criteria to progress to a definitive cluster trial are met. These include women's questionnaire return rates, prevalence of UI, and other health outcomes as reported by women at 10-12 weeks postpartum. Progress to a definitive trial however is likely to be prevented in the UK context by new perinatal pelvic health service, although this may be possible elsewhere. TRIAL REGISTRATION: https://doi.org/10.1186/ISRCTN10833250 . Registered 09/03/2020.

16.
Int J Neonatal Screen ; 8(4)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36547379

RESUMO

Tandem mass spectrometry (MS/MS) is the most universal platform currently available for the analysis of enzymatic activities and biomarkers in dried blood spots (DBS) for applications in newborn screening (NBS). Among the MS/MS applications in NBS, the most common is flow-injection analysis (FIA-) MS/MS, where the sample is introduced as a bolus injection into the mass spectrometer without the prior fractionation of analytes. Liquid chromatography combined with MS/MS (LC-MS/MS) has been employed for second-tier tests to reduce the false-positive rate associated with several nonspecific screening markers, beginning two decades ago. More recently, LC-MS/MS has been applied to primary screening for new conditions for which FIA-MS/MS or other methods, including genomic screening, are not yet adequate. In addition to providing a list of the currently used LC-MS/MS-based assays for NBS, the authors share their experience regarding the maintenance requirements of LC-MS/MS vs. FIA-MS/MS systems. The consensus is that the maintenance of LC-MS/MS and FIA-MS/MS instrumentation is similar, and LC-MS/MS has the advantage of allowing for a larger number of diseases to be screened for in a multiplex, cost-effective fashion with a high throughput and an adequate turnaround time.

17.
Drug Metab Dispos ; 39(12): 2321-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21930826

RESUMO

Intestinal secretory movement of the fluoroquinolone antibiotic, ciprofloxacin, may limit its oral bioavailability. Active ATP-binding cassette (ABC) transporters such as breast cancer resistance protein (BCRP) have been implicated in ciprofloxacin transport. The aim of this study was to test the hypothesis that BCRP alone mediates intestinal ciprofloxacin secretion. The involvement of ABC transport proteins in ciprofloxacin secretory flux was investigated with the combined use of transfected cell lines [bcrp1/BCRP-Madin-Darby canine kidney II (MDCKII) and multidrug resistance-related protein 4 (MRP4)-human embryonic kidney (HEK) 293] and human intestinal Caco-2 cells, combined with pharmacological inhibition using 3-(6-isobutyl-9-methoxy-1,4-dioxo-1,2,3,4,6, 7,12,12a-octahydropyrazino[1',2':1,6]pyrido[3,4-b]indol-3-yl)-propionic acid tert-butyl ester (Ko143), cyclosporine, 3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid (MK571), and verapamil as ABC-selective inhibitors. In addition, the regional variation in secretory capacity was investigated using male Han Wistar rat intestine mounted in Ussing chambers, and the first indicative measurements of ciprofloxacin transport by ex vivo human jejunum were made. Active, Ko143-sensitive ciprofloxacin secretion was observed in bcrp1-MDCKII cell layers, but in low-passage (BCRP-expressing) Caco-2 cell layers only a 54% fraction was Ko143-sensitive. Ciprofloxacin accumulation was lower in MRP4-HEK293 cells than in the parent line, indicating that ciprofloxacin is also a substrate for this transporter. Ciprofloxacin secretion by Caco-2 cell layers was not inhibited by MK571. Secretory flux showed marked regional variability in the rat intestine, increasing from the duodenum to peak in the ileum. Ciprofloxacin secretion was present in human jejunum and was reduced by Ko143 but showed marked interindividual variability. Ciprofloxacin is a substrate for human and rodent BCRP. An additional pathway for ciprofloxacin secretion exists in Caco-2 cells, which is unlikely to be MRP(4)-mediated. BCRP is likely to be the dominant transport mechanism for ciprofloxacin efflux in both rat and human jejunum.


Assuntos
Transportadores de Cassetes de Ligação de ATP/fisiologia , Antibacterianos/farmacocinética , Ciprofloxacina/farmacocinética , Mucosa Intestinal/metabolismo , Proteínas de Neoplasias/fisiologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Animais , Disponibilidade Biológica , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase , Ratos , Ratos Wistar
18.
Curr Opin Cell Biol ; 6(6): 877-82, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7880537

RESUMO

A growing family of kinases and phosphatases controls the activity of the cyclin-dependent kinase cdc2. The past year has seen the identification of the cdk activating kinase as well as considerable elucidation of the cdc25/wee1 regulatory pathways. Both cdc25 and wee1 appear to be regulated by upstream kinase/phosphatase networks. In addition, it is likely that other regulatory mechanisms cooperate with the wee1/cdc25 phosphorylation systems to control the action of cdc2. Together, these elaborate checks and balances ensure that cdc2 triggers mitosis at the appropriate time.


Assuntos
Proteína Quinase CDC2/fisiologia , Proteínas de Ciclo Celular , Proteínas Nucleares , Fosfoproteínas Fosfatases/fisiologia , Proteínas Tirosina Quinases/fisiologia , Proteínas/fisiologia , Animais , Ativação Enzimática , Humanos , Fator Promotor de Maturação/fisiologia , Proteínas de Schizosaccharomyces pombe , Fosfatases cdc25
19.
Nat Med ; 6(10): 1115-20, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11017142

RESUMO

To determine whether uncoupling respiration from oxidative phosphorylation in skeletal muscle is a suitable treatment for obesity and type 2 diabetes, we generated transgenic mice expressing the mitochondrial uncoupling protein (Ucp) in skeletal muscle. Skeletal muscle oxygen consumption was 98% higher in Ucp-L mice (with low expression) and 246% higher in Ucp-H mice (with high expression) than in wild-type mice. Ucp mice fed a chow diet had the same food intake as wild-type mice, but weighed less and had lower levels of glucose and triglycerides and better glucose tolerance than did control mice. Ucp-L mice were resistant to obesity induced by two different high-fat diets. Ucp-L mice fed a high-fat diet had less adiposity, lower levels of glucose, insulin and cholesterol, and an increased metabolic rate at rest and with exercise. They were also more responsive to insulin, and had enhanced glucose transport in skeletal muscle in the setting of increased muscle triglyceride content. These data suggest that manipulating respiratory uncoupling in muscle is a viable treatment for obesity and its metabolic sequelae.


Assuntos
Proteínas de Transporte/genética , Resistência à Insulina/genética , Proteínas de Membrana/genética , Músculo Esquelético/fisiologia , Obesidade/prevenção & controle , Desacopladores/metabolismo , Animais , Peso Corporal/genética , Proteínas de Transporte/metabolismo , Respiração Celular , Dieta , Feminino , Glucose/metabolismo , Canais Iônicos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais , Obesidade/genética , Proteína Desacopladora 1
20.
Trials ; 22(1): 512, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34340694

RESUMO

BACKGROUND: Financial incentives are an effective way of helping women to stop smoking during pregnancy. Unfortunately, most women who stop smoking at this time return to smoking within 12 months of the infant's birth. There is no evidence for interventions that are effective at preventing postpartum smoking relapse. Financial incentives provided after the birth may help women to sustain cessation. This randomised controlled trial will assess the effectiveness and cost-effectiveness of financial incentives to help women who are abstinent from smoking at end-of-pregnancy to avoid return to smoking up to 12 months postpartum. METHODS: This is a UK-based, multi-centre, three-arm, superiority, parallel group, individually randomised controlled trial, with 1:1:1 allocation. It will compare the effectiveness of two financial incentive interventions with each other (one intervention for up to 3 months postpartum offering up to £120 of incentives (£60 for the participant and £60 for a significant other support); the other for up to 12 months postpartum with up to £300 of incentives (£240 for the participant and £60 for a significant other support) and with a no incentives/usual care control group. Eligible women will be between 34 weeks gestation and 2 weeks postpartum, abstinent from smoking for at least 4 weeks, have an expired carbon monoxide (CO) reading < 4 parts per million (ppm), aged at least 16 years, intend remaining abstinent from smoking after the birth and able to speak and read English. The primary outcome is self-reported, lapse-free, smoking abstinence from the last quit attempt in pregnancy until 12 months postpartum, biochemically validated by expired CO and/or salivary cotinine or anabasine. Outcomes will be analysed by intention-to-treat and regression models used to compare the proportion of abstinent women between the two intervention groups and between each intervention group and the control group. An economic evaluation will assess the cost-effectiveness of offering incentives and a qualitative process evaluation will examine barriers and facilitators to trial retention, effectiveness and implementation. DISCUSSION: This pragmatic randomised controlled trial will test whether offering financial incentives is effective and cost-effective for helping women to avoid smoking relapse during the 12 months after the birth of their baby. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number 55218215 . Registered retrospectively on 5th June 2019.


Assuntos
Motivação , Abandono do Hábito de Fumar , Feminino , Humanos , Lactente , Estudos Multicêntricos como Assunto , Período Pós-Parto , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Fumar/efeitos adversos
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