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1.
Cell ; 137(6): 1005-17, 2009 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-19524505

RESUMO

Therapeutic strategies based on modulation of microRNA (miRNA) activity hold great promise due to the ability of these small RNAs to potently influence cellular behavior. In this study, we investigated the efficacy of a miRNA replacement therapy for liver cancer. We demonstrate that hepatocellular carcinoma (HCC) cells exhibit reduced expression of miR-26a, a miRNA that is normally expressed at high levels in diverse tissues. Expression of this miRNA in liver cancer cells in vitro induces cell-cycle arrest associated with direct targeting of cyclins D2 and E2. Systemic administration of this miRNA in a mouse model of HCC using adeno-associated virus (AAV) results in inhibition of cancer cell proliferation, induction of tumor-specific apoptosis, and dramatic protection from disease progression without toxicity. These findings suggest that delivery of miRNAs that are highly expressed and therefore tolerated in normal tissues but lost in disease cells may provide a general strategy for miRNA replacement therapies.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , MicroRNAs/uso terapêutico , Animais , Ciclina D2 , Ciclinas/metabolismo , Dependovirus/genética , Modelos Animais de Doenças , Vetores Genéticos , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética
2.
J Dairy Sci ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642660

RESUMO

An experiment was conducted to identify the factors that cause reduced production of cows fed a diet with high corn distiller's grains with solubles (DDGS). We hypothesized that the factors could be high S content in DDGS which may directly (S toxicity) or indirectly [dietary cation-anion difference (DCAD)] cause reduced production. We also hypothesized that high polyunsaturated fatty acids (PUFA) in DDGS could be another major factor. In a randomized complete block design, 60 lactating cows (15 primiparous and 45 multiparious; average ± SD at the beginning of the trial: milk yield, 44.0 ± 6.9 kg/d; DIM, 123 ± 50; BW, 672 ± 82 kg) were blocked and cows in each block were randomly assigned to one of the following treatments: SBM [4.7% fatty acids (FA), 0.22% S, and 178 mEq/kg DM of DCAD], a diet containing soybean meal as the main protein source; DG, SBM replacing mainly soybean byproducts and supplemental fat with DG at 30% dietary DM (4.7% FA, 0.44% S, and 42 mEq/kg DM of DCAD); SBM+S, SBM with sodium bisulfate for additional dietary S (4.8% FA, 0.37% S, and 198 mEq/kg DM of DCAD); SBM+CO, SBM with corn oil (4.7% FA, 0.23%, and 165 mEq/kg DM of DCAD); and DG+DCAD, DG with increased DCAD (4.7% FA, 0.40% S, and 330 mEq/kg DM of DCAD). Due to the limited tie stalls, the blocks of 1 to 6 started the experiment first as phase 1 and the rest of the blocks as phase 2 started the experiment after phase 1. All cows were fed the SBM diet for 10 d as a covariate period followed by the experimental period for 35 d. Data were analyzed using the PROC MIXED of SAS, block and phase were random effects and treatments, repeated wk, and interaction were fixed effects. There was an interaction of wk by treatment for DMI. While milk yield did not change, milk fat concentration tended to decrease (2.78 vs. 3.34%) for DG compared with SBM. Dry matter, OM, NDF, and CP digestibilities were lower when cows were fed the DG diet compared with SBM. Additionally, cows fed DG had lower blood concentrations of HCO3-, base excess, and tCO2 compared with SBM. The SBM+S diet did not affect production, nutrient digestibility, or blood parameters when compared with SBM. The SBM+CO diet decreased milk fat concentration and yield compared with SBM. The DG+DCAD diet tended to increase milk fat yield and concentration (1.24 vs. 1.47 kg/d; 2.78 vs. 3.37%) and increased ECM (40.9 vs. 45.1 kg/d) compared with DG but did not improve nutrient digestibility. However, blood HCO3-, base excess, and tCO2 were greater for DG+DCAD compared with DG. In conclusion, the indirect role of S-, altering DCAD, along with the high PUFA content in DDGS appears to be the factors causing reduced production responses to a high DDGS diet. Increasing DCAD to 300 mEq/kg DM in a high DDGS diet can be a feeding strategy to alleviate the reduced production responses.

3.
J Dairy Sci ; 107(7): 4524-4536, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38395396

RESUMO

The objective of the experiment was to determine the effects of supplemental SFA sources, lysophospholipids (LPL), and their interaction on production and nutrient digestibility in lactating dairy cows. The experiment was conducted with 48 cows in a randomized complete block design. Cows were blocked (12 blocks total) by parity and days in milk and randomly assigned to 4 dietary treatments in each block (2 × 2 factorial arrangement), i.e., 2 sources of fat supplements, C16:0 (PA)- or C18:0 (SA)-enriched fat, and with or without LPL. The experiment was conducted for 6 wk to measure daily dry matter intake, milk yield, and weekly milk composition. During the last week of the experiment, spot fecal and urine samples were collected to determine total-tract nutrient digestibility. Milk samples in the last week were also collected to analyze the milk fatty acid (FA) profile. All data were analyzed using the MIXED procedure of SAS, where block was used as a random effect and FA, LPL, and the interaction of FA by LPL were used as fixed effects. Week and interactions of week by FA or LPL were included for production measures. Different sources of SFA did not affect dry matter intake and milk yield. However, the PA treatment increased (39.7 vs. 36.8 kg) energy-corrected milk compared with SA due to increased milk fat yield. No effect of LPL on production measures was observed. Total-tract digestibilities of dry matter, organic matter, crude protein, and total FA were not different between the PA and SA groups, but PA increased (41.4% vs. 38.8%) neutral detergent fiber digestibility compared with SA. Supplementation of LPL increased (64.7% vs. 60.5%) total FA digestibility, especially 18-carbon FA (74.1% vs. 68.2%). An interaction of SFA by LPL was found for 16-carbon FA digestibility. The PA diet increased the concentration of 16-carbon FA in milk fat and SA increased the concentration of preformed FA (≥18 carbons). Supplementation of LPL decreased the concentration of trans-10 C18:1. No difference in N utilization and excretion among treatments was observed. In conclusion, the PA diet was more effective in improving milk fat yield of lactating cows compared with SA. Supplementation of LPL increased digestibility of total FA, especially 18-carbon FA but did not affect production.


Assuntos
Dieta , Digestão , Ácidos Graxos , Lactação , Lisofosfolipídeos , Leite , Animais , Bovinos , Feminino , Leite/química , Leite/metabolismo , Dieta/veterinária , Lisofosfolipídeos/metabolismo , Digestão/efeitos dos fármacos , Ração Animal , Suplementos Nutricionais , Nutrientes/metabolismo
4.
J Invertebr Pathol ; 197: 107886, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646414

RESUMO

The microsporidian diversity catalogued so far has resulted in the development of several taxonomic groups, one of which is the Enterocytozoonida - a group of generalist 'ultimate opportunists', which infect many fished and aquacultured animals, as well as a broad suite of host taxa, including humans. In this study, we provide phylogenetic, ultrastructural, developmental, and pathological evidence for the creation of a new genus and species to hold a microsporidian parasite of the Jonah crab, Cancer borealis. Cancer borealis represents a species of commercial interest and has become the target of a recently developed fishery on the USA and Canadian Atlantic coast. This species was found to harbour a microsporidian parasite that develops in the cytoplasm of alpha and beta cells of the hepatopancreas. We retrieved a 937 bp fragment of the parasite SSU region, alongside developmental and ultrastructural data that suggests this species is âˆ¼ 87 % similar to Parahepatospora carcini and develops in a similar manner in direct association with the host cell cytoplasm. The mature spores are ovoid in shape and measure 1.48 ± 0.15 µm (SD) in length and 1.00 ± 0.11 µm (SD) in width. Phylogenetically, the new parasite clades in the Enterocytozoonida on the same branch as P. carcini. We provide a new genus and species to hold the parasite: Pseudohepatospora borealis n. gen. n. sp. (Microsporidia: Enterocytozoonida) and explore the likelihood that this species may fit into the Hepatoporidae family.


Assuntos
Braquiúros , Microsporídios , Neoplasias , Humanos , Animais , Braquiúros/parasitologia , Filogenia , Canadá , Microsporídios/genética
5.
J Foot Ankle Surg ; 61(2): 298-304, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34565665

RESUMO

Ulceration or reulceration is a common complication following partial or total fifth ray amputations. The primary aim of this study was to evaluate the incidence of reulceration following partial fifth ray amputations. This was a multicenter review of 117 consecutive limbs that underwent partial fifth ray amputations at the University of Pittsburgh Medical Center and Wake Forest Baptist Medical Centers. Procedures were performed at various levels along the fifth metatarsal. Incidence of postoperative ulceration was evaluated on the ipsilateral foot. We hypothesized there would be an association between location of resection and development of reulceration. Seventy-one of 117 patients (60.7%) experienced repeat ulceration following a partial fifth ray amputation. Median follow-up time was 19 months. There was no statistical difference based on location of amputation (proximal, middle, distal, isolated base) with regards to reulceration (p = .166), further amputation (p = .271), transmetatarsal amputation (p = .160), or below knee amputation (p = .769). There was statistical significance in the follow up time between study sites (p = .013), fifth ray amputation reoperation rate between study sites (p = .001), and reulceration rates between study sites (p = .017). Partial fifth ray amputations can be a good initial salvage procedure to clear infection and prolong bipedal ambulatory status. The results of the present study put forward that there is not an association between location of amputations of the fifth ray and development of reulceration, transfer lesions or more proximal amputations.


Assuntos
Pé Diabético , Amputação Cirúrgica/métodos , Pé Diabético/cirurgia , Pé/cirurgia , Humanos , Incidência , Reoperação , Estudos Retrospectivos
6.
Phys Rev Lett ; 126(2): 025001, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512226

RESUMO

Inertial confinement fusion seeks to create burning plasma conditions in a spherical capsule implosion, which requires efficiently absorbing the driver energy in the capsule, transferring that energy into kinetic energy of the imploding DT fuel and then into internal energy of the fuel at stagnation. We report new implosions conducted on the National Ignition Facility (NIF) with several improvements on recent work [Phys. Rev. Lett. 120, 245003 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.245003; Phys. Rev. E 102, 023210 (2020)PRESCM2470-004510.1103/PhysRevE.102.023210]: larger capsules, thicker fuel layers to mitigate fuel-ablator mix, and new symmetry control via cross-beam energy transfer; at modest velocities, these experiments achieve record values for the implosion energetics figures of merit as well as fusion yield for a NIF experiment.

7.
J Invertebr Pathol ; 184: 107652, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34358554

RESUMO

Say's mud crab, Dyspanopeus sayi (Brachyura: Panopeidae) is a native shallow subtidal and inter-tidal inhabitant of the Atlantic coastline of North America and an invasive species in the Mediterranean and Black Seas. Little is known about the microparasites of this host and the broader Panopeidae. We describe a novel microsporidian parasite infecting the musculature of D. sayi from Malagash, Nova Scotia (Canada), at a prevalence of 7%. Histopathology and molecular diagnostics were used to describe pathology and parasite phylogenetics, respectively. Based on SSU rDNA gene sequencing we propose that the microsporidian requires establishment of a new genus (Panopeispora n. gen.) and species (Panopeispora mellora n. sp.), due to significant differences to closest known taxa (e.g. Facilispora margolisi [81% similarity] and Thelohania butleri [80% similarity]), residing in Clade V of the Microsporidia. Archived, wax-embedded histological material was re-processed for transmission electron microscopy to obtain preliminary details of its intracellular development cycle and ultrastructure within the host musculature. The discovery of this pathogen is discussed with relevance to microsporidian taxonomy and the potential for achieving ultrastructural data from archived material.


Assuntos
Braquiúros/parasitologia , Microsporídios/classificação , Animais , Nova Escócia
8.
N Z Vet J ; 69(6): 337-342, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34085907

RESUMO

AIMS: To compare the mechanical performance and mode of failure in four-point bending of two different 2.0 mm "string of pearls" locking plates that differ in dimensions. METHODS: Ten *2.0 mm, 82 mm long, 10-hole (Plate A) and ten 2.0 mm, 69 mm long, 12-hole (Plate B) Cortical Pearl Systems were secured to plate extenders and centred beneath an Instron tensile tester in four-point bending. In all constructs, a simulated fracture gap was maintained at 33 mm. Due to differences in plate dimensions, 33 mm corresponded to four pearls (Plate A) and six pearls (Plate B). Following an initial preload of 10 N, ramped single-cycle load-to-failure at 0.1 mm/second was performed in five Plate A and five Plate B constructs. Load and displacement were recorded. Constant frequency sinusoidal cyclic loading (33 N) at 20 mm/minute was performed on five Plate A and five Plate B constructs following 10 N of preload. Maximum moment and cycle count were recorded. Testing and data analysis were completed in accordance with the American Society for Testing and Materials F382-14 guidelines. Differences in performance and mode of failure were compared. RESULTS: : Plate A constructs produced higher mean values for bending stiffness (19.8 (SD 2.0) N/mm vs. 10.1 (SD 0.6) N/mm; p < 0.001), bending structural stiffness (0.77 (SD 0.08) Nm2 vs. 0.39 (SD 0.02) Nm2; p < 0.001), yield point (64.1 (SD 4.2) N vs. 54.6 (SD 3.9) N; p = 0.01), proof load (65.4 (SD 3.2) N vs. 55.6 (SD 4.0) N; p = 0.005), and bending strength (1.3 (SD 0.1) Nm vs. 1.1 (SD 0.08) Nm; p = 0.005) when compared to Plate B constructs in single cycle load-to-failure. Plate A constructs had a greater (p = 0.001) mean cycle count to failure (26,178 (SD 4,061) cycles) when compared with Plate B constructs (15,550 (SD 1,291) cycles). All plates failed by non-catastrophic plastic deformation. CONCLUSIONS: Plate A, which is wider, thicker and has a greater spacing between pearls, was mechanically superior to Plate B in four-point bending under single-cycle load-to-failure and sinusoidal cyclic loading. CLINICAL RELEVANCE: Although mechanical differences were identified in four-point bending, in vivo biomechanical performance remains undetermined. By selecting Plate B, the clinician may gain bone purchase through a greater number of pearls and thus screws per unit length, however, the inferior mechanical characteristics, as evaluated in four-point bending, should also be considered. Further research into the mechanical and biomechanical performance of these plating systems is warranted.


Assuntos
Fixação Interna de Fraturas , Fraturas Ósseas , Animais , Fenômenos Biomecânicos , Placas Ósseas/veterinária , Fixação Interna de Fraturas/veterinária , Fraturas Ósseas/veterinária
9.
Proc Natl Acad Sci U S A ; 114(44): 11745-11750, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29078330

RESUMO

Transplantation of pancreatic islets for treating type 1 diabetes is restricted to patients with critical metabolic lability resulting from the need for immunosuppression and the shortage of donor organs. To overcome these barriers, we developed a strategy to macroencapsulate islets from different sources that allow their survival and function without immunosuppression. Here we report successful and safe transplantation of porcine islets with a bioartificial pancreas device in diabetic primates without any immune suppression. This strategy should lead to pioneering clinical trials with xenotransplantation for treatment of diabetes and, thereby, represents a previously unidentified approach to efficient cell replacement for a broad spectrum of endocrine disorders and other organ dysfunctions.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 1/terapia , Ilhotas Pancreáticas/cirurgia , Animais , Feminino , Terapia de Imunossupressão/métodos , Transplante das Ilhotas Pancreáticas/métodos , Primatas , Suínos , Transplante Heterólogo/métodos
10.
Eur J Neurol ; 25(1): 13-23, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28816394

RESUMO

Inflammatory idiopathic myopathies are a group of autoimmune diseases affecting predominantly the proximal skeletal muscles, with raised muscle enzymes, with or without skin involvement and extramuscular organ involvement. Autoantibodies help to characterize patients into different clinical phenotypes. Successful treatment necessitates controlling inflammation early with corticosteroids and invariably requires additional immunosuppressive therapy. This review focuses on the aetiology, pathogenesis, clinical presentation, investigations and management of patients presenting with inflammatory idiopathic myopathies, predominantly focusing on polymyositis and antisynthetase syndrome.


Assuntos
Doenças Autoimunes/diagnóstico , Imunossupressores/uso terapêutico , Miosite/diagnóstico , Autoanticorpos/imunologia , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/patologia , Diagnóstico Diferencial , Humanos , Músculo Esquelético/patologia , Miosite/tratamento farmacológico , Miosite/patologia , Resultado do Tratamento
12.
Phys Rev Lett ; 118(25): 251301, 2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28696731

RESUMO

New results are reported from the operation of the PICO-60 dark matter detector, a bubble chamber filled with 52 kg of C_{3}F_{8} located in the SNOLAB underground laboratory. As in previous PICO bubble chambers, PICO-60 C_{3}F_{8} exhibits excellent electron recoil and alpha decay rejection, and the observed multiple-scattering neutron rate indicates a single-scatter neutron background of less than one event per month. A blind analysis of an efficiency-corrected 1167-kg day exposure at a 3.3-keV thermodynamic threshold reveals no single-scattering nuclear recoil candidates, consistent with the predicted background. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.4×10^{-41} cm^{2} for a 30-GeV c^{-2} WIMP, more than 1 order of magnitude improvement from previous PICO results.

13.
Lupus ; 26(5): 504-509, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28394235

RESUMO

Neuropsychiatric symptoms occur commonly in patients with systemic lupus erythematosus, but they are not always due to active disease. It is crucial to identify cases that are due to active systemic lupus erythematosus so that appropriate treatment can be instituted. There is no single serological or imaging test that distinguishes active neuropsychiatric systemic lupus erythematosus from neuropsychiatric manifestations caused by other factors such as infection. Most patients with neuropsychiatric systemic lupus erythematosus have generalised features of disease activity. Raised anti-dsDNA and low C3 complement levels are often seen, but are not an invariable guide. The presence of antiphospholipid antibodies is more suggestive of thrombotic than inflammatory causation. A number of other autoantibody tests have been proposed as biomarkers for neuropsychiatric systemic lupus erythematosus, but results in clinical studies have been inconsistent and none has so far entered routine clinical practice. Cerebrospinal fluid features and magnetic resonance imaging appearances are non-specific in neuropsychiatric systemic lupus erythematosus, but are useful in excluding other causes of neuropsychiatric symptoms. Newer magnetic resonance imaging sequences show promise for distinguishing new neuropsychiatric systemic lupus erythematosus activity from previous damage and recent research suggests these may correlate with changes in cognitive function in patients with systemic lupus erythematosus. However, formal cognitive testing is seldom carried out in the acute setting.


Assuntos
Disfunção Cognitiva/diagnóstico , Lúpus Eritematoso Sistêmico/complicações , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Neuroimagem/métodos , Diagnóstico Diferencial , Feminino , Humanos , Lúpus Eritematoso Sistêmico/líquido cefalorraquidiano , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X
14.
Ultrasound Obstet Gynecol ; 49(6): 761-768, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27854379

RESUMO

OBJECTIVE: Fetal growth restriction (FGR) is a powerful determinant of poor perinatal outcome. From our previous work in pregnancies at high risk of development of hypertension we found impaired cardiovascular adaptation early in gestation in those destined to deliver growth-restricted infants. In this study, we monitored serially maternal hemodynamics from the first to third trimester in a similar high-risk cohort, in order to determine whether this distinct hemodynamic profile found at presentation persisted throughout pregnancy in those complicated by FGR. METHODS: This was a prospective observational study based at a specialist antenatal hypertension clinic at a tertiary hospital in London. Maternal hemodynamics were evaluated serially using a non-invasive bioreactance method in pregnant women referred to the clinic with a history of chronic hypertension or a history of hypertensive disorder in a previous pregnancy. Differences in maternal hemodynamic parameters were compared between women who delivered a baby with a birth weight ≥ 10th vs < 10th percentile and ≥ 5th vs < 5th percentile. RESULTS: Eighty-four pregnant women were included in the study. Mean gestational age at presentation was 14.3 weeks. Sixteen women delivered babies with a birth weight < 10th percentile and 11 with a birth weight < 5th percentile. In pregnancies with a birth weight ≥ 10th percentile, longitudinal maternal hemodynamics showed a pattern consistent with well-established physiological changes in pregnancy, i.e. a reduction in vascular resistance and an increase in cardiac output with advancing gestation until mid-pregnancy. However, women who delivered babies with a birth weight < 10th percentile showed a static pattern with no change during gestation and lower cardiac output and higher peripheral vascular resistance. Similar differences were seen when the 5th percentile was used to discriminate between appropriately-grown and growth-restricted babies. CONCLUSION: Serial assessment of maternal hemodynamics in high-risk women identifies distinctive trends associated with pregnancies destined to deliver babies with birth weights < 10th and < 5th percentiles. These pregnancies have a suppressed and static maternal cardiac output and stroke volume, and have consistently raised peripheral vascular resistance. This suggests that, in women with chronic hypertension or a history of hypertensive disorder in a previous pregnancy, FGR is associated with a primary and persistent failure of maternal cardiovascular adaptation in pregnancy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Retardo do Crescimento Fetal/diagnóstico , Hipertensão Induzida pela Gravidez/diagnóstico , Diagnóstico Pré-Natal , Adulto , Peso ao Nascer , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/fisiopatologia , Hemodinâmica , Humanos , Hipertensão Induzida pela Gravidez/fisiopatologia , Recém-Nascido , Estudos Longitudinais , Gravidez , Resultado da Gravidez , Estudos Prospectivos
15.
Ultrasound Obstet Gynecol ; 49(1): 95-103, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27800645

RESUMO

OBJECTIVES: To examine whether treatment for hypertension in pregnancy that is guided by serial monitoring of maternal central hemodynamics leads to a reduction in the rate of severe hypertension, defined as blood pressure ≥ 160/110 mmHg; and to assess the distinct longitudinal hemodynamic profiles associated with beta-blocker monotherapy, vasodilator monotherapy and dual agent therapy, and their relationships with outcomes, including fetal growth restriction. METHODS: This was a prospective observational study at a dedicated antenatal hypertension clinic in a tertiary UK hospital. Fifty-two untreated women presenting with hypertension were recruited consecutively and started on treatment, either with a beta-blocker or a vasodilator. The choice of initial antihypertensive agent was determined according to a model constructed previously to predict the response to the beta-blocker labetalol in pregnant women needing antihypertensive treatment. At presentation, the demographic and maternal hemodynamic variables associated with a therapeutic response to labetalol, defined as blood pressure control < 140/90 mmHg with labetalol monotherapy throughout pregnancy, were ascertained and analyzed with logistic regression to create a model to predict sustained blood pressure control as described above. The women were reviewed regularly until delivery and underwent serial hemodynamic monitoring throughout pregnancy. If their blood pressure was elevated, the prediction model was referred to again to determine if alternative antihypertensive therapy, either with additional beta-blocker or a vasodilator, should be added. RESULTS: Treatment by referring to results of serial hemodynamic monitoring reduced the rate of severe antenatal hypertension from 18% to 3.8%. Seventy-seven percent of women were initially prescribed a beta-blocker and 23% a vasodilator. The group that maintained good blood pressure control with beta-blocker monotherapy had the best fetal and maternal outcomes. They had lower blood pressures at presentation and throughout gestation, demonstrated well-maintained cardiac output and had the lowest rates of fetal growth restriction. The groups that required dual therapy to control their blood pressure had persistently higher blood pressure and rate of fetal growth restriction. The groups that required vasodilator therapy due to high levels of peripheral vascular resistance, either at presentation or later in pregnancy, accounted for 81% of cases with fetal growth restriction. CONCLUSION: Using serial hemodynamic monitoring in pregnancy to guide treatment of hypertension significantly reduces the rate of severe hypertension and allows identification of high-resistance, low-output hypertensive pregnancies that are associated with an increased rate of fetal growth restriction. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. RESUMEN OBJETIVOS: Examinar si el tratamiento para la hipertensión en el embarazo guiado por un seguimiento en serie de las principales constantes hemodinámicas de la madre conduce a una reducción en la tasa de hipertensión grave, definida como presión arterial ≥ 160/110 mmHg; y evaluar los diferentes perfiles hemodinámicos longitudinales asociados a la monoterapia con beta-bloqueantes, la monoterapia con vasodilatadores y la terapia dual, y su relación con los resultados, como la restricción del crecimiento fetal. MÉTODOS: Se realizó un estudio observacional prospectivo en una clínica especializada en hipertensión prenatal de un hospital de atención terciaria del Reino Unido. Se reclutaron consecutivamente a cincuenta y dos mujeres no tratadas que presentaban hipertensión y se comenzó a tratarlas, bien con un beta-bloqueante o bien con un vasodilatador. La elección del agente antihipertensivo inicial se determinó de acuerdo con un modelo elaborado previamente para predecir la respuesta al beta-bloqueante labetalol en mujeres embarazadas que necesitaban tratamiento antihipertensivo. Al inicio se registraron las características demográficas y las variables hemodinámicas maternas asociadas con una respuesta terapéutica al labetalol, definida como un control de la presión arterial < 140/90 mmHg con monoterapia de labetalol durante todo el embarazo que se analizó mediante regresión logística para crear un modelo con el que pronosticar un control sostenido de la presión arterial, como se describe arriba. Las mujeres fueron sometidas a revisiones regulares hasta el momento del parto y se les hizo un seguimiento hemodinámico en serie durante todo el embarazo. Si la presión arterial era elevada, se empleó de nuevo el modelo de predicción para determinar si se debería añadir un tratamiento antihipertensivo alternativo, ya sea con un beta-bloqueante adicional o con un vasodilatador. RESULTADOS: El tratamiento que tuvo en cuenta los resultados del seguimiento hemodinámico en serie redujo la tasa de hipertensión prenatal grave del 18% al 3,8%. Al 77% de las mujeres se les recetó inicialmente un y al 23% un vasodilatador. El grupo que mantuvo un buen control de la presión arterial con monoterapia de beta-bloqueantes logró mejores resultados fetales y maternos. Este grupo tuvo menor presión arterial al inicio y durante toda la gestación, mostró un gasto cardíaco en buen estado y tuvo las tasas más bajas de restricción del crecimiento fetal. Los grupos que requirieron terapia dual para controlar su presión arterial mostraron persistentemente una mayor presión arterial y un mayor ritmo de restricción del crecimiento fetal. Los grupos que requirieron tratamiento vasodilatador debido a los altos niveles de resistencia vascular periférica, tanto al inicio como durante el embarazo, representaron el 81% de los casos con restricción del crecimiento fetal. CONCLUSIÓN: El uso de un seguimiento hemodinámico en serie en el embarazo como guía para el tratamiento de la hipertensión reduce significativamente la tasa de hipertensión severa y permite la identificación de embarazos con hipertensión de alta resistencia y malos resultados, asociados con una mayor tasa de restricción del crecimiento fetal. : (≥ 160/110 mmHg);ß、,()。 : 。52、,ß。ß。,(<140/90 mmHg),logistic,。,。,(ß)。 : ,18%3.8%。77%ß,23%。ß。,,。,。,81%。 : ,,、。.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Retardo do Crescimento Fetal/etiologia , Hipertensão/tratamento farmacológico , Vasodilatadores/uso terapêutico , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Feminino , Hemodinâmica , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Gravidez , Estudos Prospectivos , Resultado do Tratamento , Vasodilatadores/farmacologia
16.
Pediatr Transplant ; 21(6)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28635157

RESUMO

The use of DBSs for home monitoring has been limited due to unsatisfactory blood sampling and analytical difficulties. The aim of this longitudinal feasibility trial was to assess the utility of DBS to monitor TAC and Cr at home in transplant recipients. A total of 30 participants (2-21 years, mean±SD, 13.6±5.4 year) were enrolled over 12 months. Eighteen were males. Monthly DBS samples were obtained at home and mailed to the central laboratory for analysis of TAC and Cr. Nineteen patients completed the study, and 216 cards were received in the laboratory from a total of 279 cards expected, with 416/519 (80%) blood spots being suitable for analysis. We found a high correlation between blood TAC and Cr levels by DBS and the clinical laboratory, R2 =.81 and .95, respectively. Fifteen parents and 15 youth completed measures of satisfaction with and preference for DBS testing. All but one parent/caregiver and youth reported satisfaction and preference for this method of testing over laboratory blood draws. We conclude that home DBS monitoring is a feasible method to monitor TAC and Cr in pediatric transplant recipients.


Assuntos
Teste em Amostras de Sangue Seco , Monitoramento de Medicamentos/métodos , Serviços de Assistência Domiciliar , Imunossupressores/sangue , Transplante de Rim , Cuidados Pós-Operatórios/métodos , Tacrolimo/sangue , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Creatinina/sangue , Estudos de Viabilidade , Feminino , Humanos , Estudos Longitudinais , Masculino , Adesão à Medicação/estatística & dados numéricos , Preferência do Paciente/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
17.
J Appl Microbiol ; 123(6): 1584-1596, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28940494

RESUMO

AIMS: Test the choice of 16S rRNA gene amplicon and data analysis method on the accuracy of identification of clinically important bacteria utilizing a benchtop sequencer. METHODS AND RESULTS: Nine 16S rRNA amplicons were tested on an Ion Torrent PGM to identify 41 strains of clinical importance. The V1-V2 region identified 40 of 41 isolates to the species level. Three data analysis methods were tested, finding that the Ribosomal Database Project's SequenceMatch outperformed BLAST and the Ion Reporter Metagenomics analysis pipeline. Lastly, 16S rRNA gene sequencing mixtures of four species through a six log range of dilution showed species were identifiable even when present as 0·1% of the mixture. CONCLUSIONS: Sequencing the V1-V2 16S rRNA gene region, made possible by the increased read length Ion Torrent PGM sequencer's 400 base pair chemistry, may be a better choice over other commonly used regions for identifying clinically important bacteria. In addition, the SequenceMatch algorithm, freely available from the Ribosomal Database Project, is a good choice for matching filtered reads to organisms. Lastly, 16S rRNA gene sequencing's sensitivity to the presence of a bacterial species at 0·1% of a mixture suggests it has sufficient sensitivity for samples in which important bacteria may be rare. SIGNIFICANCE AND IMPACT OF THE STUDY: We have validated 16S rRNA gene sequencing on a benchtop sequencer including simple mixtures of organisms; however, our results highlight deficits for clinical application in place of current identification methods.


Assuntos
Bactérias/classificação , RNA Ribossômico 16S/química , Análise de Sequência de DNA/métodos , Bactérias/isolamento & purificação , Sequência de Bases , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/instrumentação
18.
J Neurophysiol ; 116(2): 438-47, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27146984

RESUMO

The influence of hyperpolarization-activated cation current (h-current; Ih) upon synaptic integration in paravertebral sympathetic neurons was studied together with expression of hyperpolarization-activated cyclic nucleotide-gated (HCN) subunit isoforms. All four HCN subunits were detected in homogenates of the rat superior cervical ganglion (SCG) using the PCR to amplify reverse-transcribed messenger RNAs (RT-PCR) and using quantitative PCR. Voltage clamp recordings from dissociated SCG neurons at 35°C detected Ih in all cells, with a maximum hyperpolarization-activated cation conductance of 1.2 ± 0.1 nS, half-maximal activation at -87.6 mV, and reversal potential of -31.6 mV. Interaction between Ih and synaptic potentials was tested with virtual fast nicotinic excitatory postsynaptic potentials (EPSPs) created with dynamic clamp. The blocking of Ih with 15 µM ZD7288 hyperpolarized cells by 4.7 mV and increased the virtual synaptic conductance required to stimulate an action potential from 7.0 ± 0.9 nS to 12.1 ± 0.9 nS. In response to stimulation with 40 s long trains of virtual EPSPs, ZD7288 reduced postsynaptic firing from 2.2 to 1.7 Hz and the associated synaptic amplification from 2.2 ± 0.1 to 1.7 ± 0.2. Cyclic nucleotide binding to HCN channels was simulated by blocking native Ih with ZD7288, followed by reconstitution with virtual Ih using a dynamic clamp model of the voltage clamp data. Over a 30-mV range, shifting the half-activation voltage for Ih in 10 mV depolarizing increments always increased synaptic gain. These results indicate that Ih, in sympathetic neurons, can strengthen nicotinic EPSPs and increase synaptic amplification, while also working as a substrate for cyclic nucleotide-dependent modulation.


Assuntos
Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Neurônios/fisiologia , Nicotina/farmacologia , Gânglio Cervical Superior/citologia , Animais , Fenômenos Biofísicos/efeitos dos fármacos , Fenômenos Biofísicos/fisiologia , Biofísica , Estimulação Elétrica , Feminino , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Masculino , Neurônios/efeitos dos fármacos , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Técnicas de Patch-Clamp , Pirimidinas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Sinapses/efeitos dos fármacos , Interface Usuário-Computador
19.
Mol Genet Metab ; 119(3): 288-292, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27746033

RESUMO

Mathematical modeling approaches have been commonly used in complex signaling pathway studies such as the insulin signal transduction pathway. Our expanded mathematical model of the insulin signal transduction pathway was previously shown to effectively predict glucose clearance rates using mRNA levels of key components of the pathway in a mouse model. In this study, we re-optimized and applied our expanded model to study insulin sensitivity in other species and tissues (human skeletal muscle) with altered protein activities of insulin signal transduction pathway components. The model has now been optimized to predict the effect of short term exercise on insulin sensitivity for human test subjects with obesity or type II diabetes mellitus. A comparison between our extended model and the original model showed that our model better simulates the GLUT4 translocation events of the insulin signal transduction pathway and glucose uptake as a clinically relevant model output. Results from our extended model correlate with O'Gorman's published in-vivo results. This study demonstrates the ability to adapt this model to study insulin sensitivity to many biological systems (human skeletal muscle and mouse liver) with minimal changes in the model parameters.


Assuntos
Diabetes Mellitus Tipo 2/genética , Resistência à Insulina/genética , Modelos Teóricos , Obesidade/genética , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Humanos , Insulina/genética , Camundongos , Obesidade/complicações , Obesidade/patologia , Transdução de Sinais
20.
Phys Rev Lett ; 117(24): 241101, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-28009216

RESUMO

We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9} GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5} GeV to above 10^{11} GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6} GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5} GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.

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