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1.
Hum Reprod ; 39(3): 509-515, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38265302

RESUMO

STUDY QUESTION: Can women with pregnancy of unknown location (PUL) following in vitro fertilization (IVF) be risk-stratified regarding the subsequent need for medical intervention, based on their demographic characteristics and the results of serum biochemistry at the initial visit? SUMMARY ANSWER: The ratio of serum hCG to number of days from conception (hCG/C) or the initial serum hCG level at ≥5 weeks' gestation could be used to estimate the risk of women presenting with PUL following IVF and needing medical intervention during their follow-up. WHAT IS KNOWN ALREADY: In women with uncertain conception dates presenting with PUL, a single serum hCG measurement cannot be used to predict the final pregnancy outcomes, thus, serial levels are mandatory to establish a correct diagnosis. Serum progesterone levels can help to risk-stratify women at their initial visit but are not accurate in those taking progesterone supplementation, such as women pregnant following IVF. STUDY DESIGN, SIZE, DURATION: This was a retrospective study carried out at two specialist early pregnancy assessment units between May 2008 and January 2021. A total of 224 women met the criteria for inclusion, but 14 women did not complete the follow-up and were excluded from the study. PARTICIPANTS/MATERIALS, SETTING, METHODS: We selected women who had an IVF pregnancy and presented with PUL at ≥5 weeks' gestation. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 30/210 (14.0%, 95% CI 9.9-19.8) women initially diagnosed with PUL required surgical intervention. The hCG/C was significantly higher in the group of women requiring an intervention compared to those who did not (P = 0.003), with an odds ratio of 3.65 (95% CI 1.49-8.89, P = 0.004). A hCG/C <4.0 was associated with a 1.9% risk of intervention, which accounted for 25.7% of the study population. A similar result was obtained by substituting hCG/C <4.0 with an initial hCG level <100 IU/l, which was associated with 2.0% risk of intervention, and accounted for 23.8% of the study population (P > 0.05). LIMITATIONS, REASONS FOR CAUTION: A limitation of our study is that it is retrospective in nature, and as such, we were reliant on existing data. WIDER IMPLICATIONS OF THE FINDINGS: A previous study in women with PUL after spontaneous conception found that a 2% intervention rate was considered low enough to eliminate the need for close follow-up and serial blood tests. Using the same 2% cut-off, a quarter of women with PUL after IVF could also avoid attending for further visits and investigations. STUDY FUNDING/COMPETING INTEREST(S): No external funding was required for this study. No conflicts of interest are required to be declared. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Fertilização in vitro , Progesterona , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Fertilização in vitro/efeitos adversos , Fertilização in vitro/métodos , Resultado da Gravidez , Gravidez de Alto Risco
2.
J Physiol ; 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597809

RESUMO

Age-related decline in skeletal muscle structure and function can be mitigated by regular exercise. However, the precise mechanisms that govern this are not fully understood. The nucleus plays an active role in translating forces into biochemical signals (mechanotransduction), with the nuclear lamina protein lamin A regulating nuclear shape, nuclear mechanics and ultimately gene expression. Defective lamin A expression causes muscle pathologies and premature ageing syndromes, but the roles of nuclear structure and function in physiological ageing and in exercise adaptations remain obscure. Here, we isolated single muscle fibres and carried out detailed morphological and functional analyses on myonuclei from young and older exercise-trained individuals. Strikingly, myonuclei from trained individuals were more spherical, less deformable, and contained a thicker nuclear lamina than those from untrained individuals. Complementary to this, exercise resulted in increased levels of lamin A and increased myonuclear stiffness in mice. We conclude that exercise is associated with myonuclear remodelling, independently of age, which may contribute to the preservative effects of exercise on muscle function throughout the lifespan. KEY POINTS: The nucleus plays an active role in translating forces into biochemical signals. Myonuclear aberrations in a group of muscular dystrophies called laminopathies suggest that the shape and mechanical properties of myonuclei are important for maintaining muscle function. Here, striking differences are presented in myonuclear shape and mechanics associated with exercise, in both young and old humans. Myonuclei from trained individuals were more spherical, less deformable and contained a thicker nuclear lamina than untrained individuals. It is concluded that exercise is associated with age-independent myonuclear remodelling, which may help to maintain muscle function throughout the lifespan.

3.
Opt Express ; 30(8): 13252-13262, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472942

RESUMO

We describe a novel method of single-shot trap frequency measurement for a confined Bose-Einstein Condensate, which uses an atom laser to repeatedly sample the mean velocity of trap oscillations as a function of time. The method is able to determine the trap frequency to an accuracy of 39 ppm (16 mHz) in a single experimental realization, improving on the literature by a factor of three. Further, we show that by employing a reconstructive aliasing approach our method can be applied to trap frequencies more than a factor of 3 greater than the sampling frequency.

4.
Phys Rev Lett ; 125(1): 013002, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32678641

RESUMO

We present the detection of the highly forbidden 2^{3}S_{1}→3^{3}S_{1} atomic transition in helium, the weakest transition observed in any neutral atom. Our measurements of the transition frequency, upper state lifetime, and transition strength agree well with published theoretical values and can lead to tests of both QED contributions and different QED frameworks. To measure such a weak transition, we develop two methods using ultracold metastable (2^{3}S_{1}) helium atoms: low background direct detection of excited then decayed atoms for sensitive measurement of the transition frequency and lifetime, and a pulsed atom laser heating measurement for determining the transition strength. These methods could possibly be applied to other atoms, providing new tools in the search for ultraweak transitions and precision metrology.

5.
J Appl Microbiol ; 127(4): 968-984, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30927378

RESUMO

Synthetic biology requires the design and implementation of novel enzymes, genetic circuits or even entire cells, which can be controlled by the user. RNA-based regulatory elements have many important functional properties in this regard, such as their modular nature and their ability to respond to specific external stimuli. These properties have led to the widespread exploration of their use as gene regulation devices in synthetic biology. In this review, we focus on two major types of RNA elements: riboswitches and RNA thermometers (RNATs). We describe their general structure and function, before discussing their potential uses in synthetic biology (e.g. in the production of biofuels and biodegradable plastics). We also discuss their limitations, and novel strategies to implement RNA-based regulatory devices in biotechnological applications. We close with a description of some common model organisms used in synthetic biology, with a focus on the current applications and limitations of RNA-based regulation.


Assuntos
Biotecnologia/métodos , Regulação da Expressão Gênica , RNA/fisiologia , Biologia Sintética/métodos , Bactérias/genética , Bactérias/metabolismo , RNA/química , RNA Bacteriano/química , RNA Bacteriano/fisiologia , Riboswitch , Temperatura
6.
Ann Oncol ; 29(9): 1932-1938, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30060083

RESUMO

Background: Venetoclax is a selective, potent inhibitor of the anti-apoptotic B-cell leukemia/lymphoma-2 protein approved for treatment of chronic lymphocytic leukemia. We conducted a dose-finding study of venetoclax in combination with bendamustine-rituximab (BR) in patients with relapsed/refractory non-Hodgkin's lymphoma (NHL). Patients and methods: BR was given for six cycles at standard doses. Intermittent and continuous oral venetoclax administration was explored at 50-1200 mg daily doses. Co-primary objectives included safety, pharmacokinetics (PKs), maximum-tolerated dose (MTD), and recommended phase II dose (RP2D); secondary objective was preliminary efficacy. Results: Sixty patients were enrolled: 32 with follicular lymphoma, 22 with diffuse large B-cell lymphoma, and 6 with marginal zone lymphoma. Nausea (70%), neutropenia (68%), diarrhea (55%), and thrombocytopenia (52%) were the most frequent adverse events (AEs). Most common grade 3/4 AEs were neutropenia (60%) and lymphopenia (38%). Serious AEs were reported in 24 patients; the most frequent were febrile neutropenia and disease progression (8% each). Five patients died from either disease progression (n = 4) or respiratory failure (n = 1). MTD was not reached; RP2D for venetoclax-BR combination was established as 800 mg daily continuously. Venetoclax PK exposure with and without BR was comparable. For all patients, overall response rate was 65%. Median duration of overall response, overall survival, and progression-free survival was 38.3 months [95% confidence interval (CI) 10.4-NR], not yet reached, and 10.7 months (95% CI 4.3-21.0), respectively. Conclusions: This study established the safety profile of venetoclax in combination with BR, and results demonstrated tolerability and preliminary efficacy of the combination. Additional follow-up is needed to better determine the future role of BR plus venetoclax in the treatment of relapsed/refractory B-cell NHL. Trial registered: Clinicaltrials.gov, NCT01594229.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma não Hodgkin/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Cloridrato de Bendamustina/administração & dosagem , Cloridrato de Bendamustina/efeitos adversos , Cloridrato de Bendamustina/farmacocinética , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Neutropenia Febril Induzida por Quimioterapia/epidemiologia , Neutropenia Febril Induzida por Quimioterapia/etiologia , Progressão da Doença , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Intervalo Livre de Progressão , Rituximab/administração & dosagem , Rituximab/efeitos adversos , Rituximab/farmacocinética , Terapia de Salvação/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética
7.
Ultrasound Obstet Gynecol ; 49(2): 171-176, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27731538

RESUMO

OBJECTIVE: Methotrexate is used routinely worldwide for the medical treatment of clinically stable women with a tubal ectopic pregnancy. This is despite the lack of robust evidence to show its superior effectiveness over expectant management. The aim of our multicenter randomized controlled trial was to compare success rates of methotrexate against placebo for the conservative treatment of tubal ectopic pregnancy. METHODS: This study took place in two early-pregnancy units in the UK between August 2005 and June 2014. Inclusion criteria were clinically stable women with a conclusive ultrasound diagnosis of a tubal ectopic pregnancy, presenting with a low serum beta human chorionic gonadotropin (ß-hCG) level of < 1500 IU/L. Women were assigned randomly to a single systemic injection of either 50 mg/m2 methotrexate or placebo. The primary outcome was a binary indicator for success of conservative management, defined as resolution of clinical symptoms and decline of serum ß-hCG to < 20 IU/L or a negative urine pregnancy test without the need for any additional medical intervention. An intention-to-treat analysis was followed. RESULTS: We recruited a total of 80 women, 42 of whom were assigned to methotrexate and 38 to placebo. The arms of the study were matched in terms of age, ethnicity, obstetric history, pregnancy characteristics and serum levels of ß-hCG and progesterone. The rates of success were similar for the two study arms: 83% with methotrexate and 76% with placebo. On univariate analysis, this difference was not statistically significant (χ2 (1 degree of freedom) = 0.53; P = 0.47). On multivariate logistic regression, the serum level of ß-hCG was the only covariate found to be significantly associated with outcome. The odds of failure increased by 0.15% for each unit increase in ß-hCG (odds ratio, 1.0015 (95% CI, 1.0002-1.003); P = 0.02). In 14 women presenting with serum ß-hCG of 1000-1500 IU/L, the success rate was 33% in those managed expectantly compared with 62% in those receiving methotrexate. This difference was not statistically significant and a larger sample size would be needed to give sufficient power to detect a difference in the subgroup of women with higher ß-hCG. In women with successful conservative treatment, there was no significant difference in median ß-hCG resolution times between study arms (17.5 (interquartile range (IQR), 14-28.0) days (n = 30) in the methotrexate group vs 14 (IQR, 7-29.5) days (n = 25) in the placebo group; P = 0.73). CONCLUSIONS: The results of our study do not support the routine use of methotrexate for the treatment of clinically stable women diagnosed with tubal ectopic pregnancy presenting with low serum ß-hCG (< 1500 IU/L). Further work is required to identify a subgroup of women with tubal ectopic pregnancy and ß-hCG ≥ 1500 IU/L in whom methotrexate may offer a safe and cost-effective alternative to surgery. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Comparación entre una sola dosis de metotrexate sistémico y la conducta expectante en el tratamiento de casos de embarazo ectópico tubárico: un ensayo aleatorio controlado con placebo RESUMEN OBJETIVO: El metotrexate se utiliza de modo rutinario en todo el mundo para el tratamiento de las mujeres clínicamente estables con un embarazo ectópico tubárico. Esto sucede a pesar de la falta de evidencia rigurosa que demuestre que su eficacia es superior a la conducta expectante. El objetivo de este ensayo controlado aleatorio multicéntrico fue comparar las tasas de éxito del metotrexate con las de un placebo para el tratamiento cauteloso del embarazo ectópico tubárico. MÉTODOS: Este estudio se llevó a cabo en dos clínicas de control de gestación temprana en el Reino Unido entre agosto de 2005 y junio de 2014. Los criterios de inclusión fueron mujeres clínicamente estables con un diagnóstico ecográfico concluyente de embarazo ectópico tubárico, las cuáles presentaban una concentración sérica baja de la ß hormona coriónica gonadotrópica (ß-hCG) inferior a 1500 UI/L. Las mujeres fueron asignadas aleatoriamente a una sola inyección sistémica de 50 mg/m2 de metotrexate o a placebo. El resultado primario fue un indicador binario del éxito del tratamiento conservador, definido como la resolución de los síntomas clínicos y la disminución en el suero de la ß-hCG a <20 UI/L o una prueba de embarazo negativa en orina sin la necesidad de ninguna intervención médica adicional. Se hizo un análisis por intención de tratar. RESULTADOS: Se reclutó un total de 80 mujeres; a 42 de ellas se les asignó el metotrexate y a 38 el placebo. Los grupos del estudio se realizaron en función de la edad, el origen étnico, los antecedentes obstétricos, las características del embarazo y los niveles séricos de la ß-hCG y la progesterona. Las tasas de éxito fueron similares para los dos grupos de estudio: 83% con metotrexate y 76% con placebo. En el análisis univariante, esta diferencia no fue estadísticamente significativa (χ2 (1 grado de libertad) = 0,53; P = 0,47). En la regresión logística multivariante, el nivel sérico de la ß-hCG fue la única covariable que se encontró significativamente asociada con el resultado. Las probabilidades de fracaso aumentaron en un 0,15% por cada unidad de aumento de la ß-hCG (cociente de probabilidad 1,0015 (IC 95%, 1,0002-1,003); P = 0,02). La tasa de éxito en las 14 mujeres con un nivel sérico de la ß-hCG de 1000-1500 UI/L fue del 33% en las tratadas con conducta expectante frente al 62% en las que recibieron metotrexate. Esta diferencia no fue estadísticamente significativa, por lo que se necesitaría un tamaño de muestra mayor, lo suficiente como para poder detectar diferencias en el subgrupo de mujeres con una ß-hCG más elevada. En las mujeres en las que el tratamiento conservador tuvo éxito, no hubo una diferencia significativa en la mediana de los tiempos de resolución de la ß-hCG entre los grupos del estudio (17,5 (amplitud intercuartílica (IQR), 14-28,0) días (n = 30) en el grupo de metotrexate frente a 14 (IQR, 7-29.5) días (n = 25) en el grupo de placebo; P = 0,73). CONCLUSIONES: Los resultados de este estudio no apoyan el uso rutinario de metotrexate para el tratamiento de las mujeres clínicamente estables diagnosticadas con un embarazo ectópico tubárico que presenta un nivel sérico bajo la ß-hCG (<1500 UI/L). Serán necesarios estudios adicionales para identificar un subgrupo de mujeres con embarazo ectópico tubárico y ß-hCG ≥1500 UI/L para quienes el metotrexate puede ofrecer una alternativa segura y rentable en comparación con la cirugía. : : ,,。。 : 2005820146,2。,,ß(beta human chorionic gonadotropin,ß-hCG)<1500 IU/L。,(50 mg/m2 )。,ß-hCG<20 IU/L,。。 : 80,42,38。2、、、ß-hCG。2:83%,76%。,[χ2 (1)=0.53;P=0.47]。logistic,ß-hCG。ß-hCG,0.15%[,1.0015(95% CI,1.0002~1.003);P=0.02]。14ß-hCG1000~1500 IU/L,33%,62%。,ß-hCG。,2ß-hCG(P=0.73),17.5[(interquartile range,IQR),14~28.0](n=30),14 (IQR,7~29.5)(n=25)。 : 、、ß-hCG(<1500 IU/L)。,ß-hCG>1500 IU/L、。.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Metotrexato/administração & dosagem , Gravidez Tubária/tratamento farmacológico , Gravidez Tubária/cirurgia , Adulto , Feminino , Humanos , Análise de Intenção de Tratamento , Modelos Logísticos , Metotrexato/uso terapêutico , Gravidez , Gravidez Tubária/metabolismo , Resultado do Tratamento , Adulto Jovem
8.
Ultrasound Obstet Gynecol ; 47(4): 511-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26764166

RESUMO

OBJECTIVES: To assess the efficacy of ultrasound-guided suction curettage for management of pregnancies implanted into the lower uterine segment Cesarean section scar. METHODS: This was a retrospective study including women diagnosed with Cesarean section scar pregnancy at two large tertiary referral early pregnancy units between 1997 and 2014. Surgical evacuation was offered to selected women presenting in the first trimester ≤ 14 weeks' gestation. All procedures were performed transcervically under ultrasound guidance using suction curettage. A modified Shirodkar cervical suture was used in women who required additional measures to secure hemostasis. RESULTS: A total of 232 women with Cesarean section scar pregnancy were seen at the referral units; 191/232 (82.3%) women were treated surgically. The median intraoperative blood loss was 100 mL (range, 10-3000 mL); 9/191 (4.7% (95% CI, 1.7-7.7%)) women required blood transfusion and, in one (0.5% (95% CI, 0-1.5%)), life-saving hysterectomy had to be performed because of uncontrollable intraoperative bleeding. Of the women who attended for follow-up, 7/116 (6.0% (95% CI, 1.7-10.3%)) required a repeat surgical procedure because of retained products of conception. Multivariable analysis showed that the gestational sac diameter (odds ratio (OR), 1.10 (95% CI, 1.03-1.17)) and pregnancy vascularity on Doppler examination (OR, 3.41 (95% CI, 1.39-8.33)) were significant predictors of heavy intraoperative blood loss (> 1000 mL). CONCLUSIONS: Ultrasound-guided suction curettage is an effective method for the treatment of pregnancies implanted into a lower uterine segment Cesarean section scar and is associated with a low risk of blood transfusion and hysterectomy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Cicatriz/complicações , Gravidez Ectópica/cirurgia , Ultrassonografia de Intervenção/efeitos adversos , Ultrassonografia Pré-Natal/métodos , Curetagem a Vácuo/efeitos adversos , Adulto , Cesárea/efeitos adversos , Feminino , Idade Gestacional , Humanos , Complicações Pós-Operatórias/etiologia , Gravidez , Primeiro Trimestre da Gravidez , Gravidez Ectópica/diagnóstico por imagem , Gravidez Ectópica/etiologia , Estudos Retrospectivos , Ultrassonografia de Intervenção/métodos , Curetagem a Vácuo/métodos
9.
Hum Reprod ; 30(9): 2038-47, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26173606

RESUMO

STUDY QUESTION: Is salpingotomy cost effective compared with salpingectomy in women with tubal pregnancy and a healthy contralateral tube? SUMMARY ANSWER: Salpingotomy is not cost effective over salpingectomy as a surgical procedure for tubal pregnancy, as its costs are higher without a better ongoing pregnancy rate while risks of persistent trophoblast are higher. WHAT IS KNOWN ALREADY: Women with a tubal pregnancy treated by salpingotomy or salpingectomy in the presence of a healthy contralateral tube have comparable ongoing pregnancy rates by natural conception. Salpingotomy bears the risk of persistent trophoblast necessitating additional medical or surgical treatment. Repeat ectopic pregnancy occurs slightly more often after salpingotomy compared with salpingectomy. Both consequences imply potentially higher costs after salpingotomy. STUDY DESIGN, SIZE, DURATION: We performed an economic evaluation of salpingotomy compared with salpingectomy in an international multicentre randomized controlled trial in women with a tubal pregnancy and a healthy contralateral tube. Between 24 September 2004 and 29 November 2011, women were allocated to salpingotomy (n = 215) or salpingectomy (n = 231). Fertility follow-up was done up to 36 months post-operatively. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: We performed a cost-effectiveness analysis from a hospital perspective. We compared the direct medical costs of salpingotomy and salpingectomy until an ongoing pregnancy occurred by natural conception within a time horizon of 36 months. Direct medical costs included the surgical treatment of the initial tubal pregnancy, readmissions including reinterventions, treatment for persistent trophoblast and interventions for repeat ectopic pregnancy. The analysis was performed according to the intention-to-treat principle. MAIN RESULTS AND THE ROLE OF CHANCE: Mean direct medical costs per woman in the salpingotomy group and in the salpingectomy group were €3319 versus €2958, respectively, with a mean difference of €361 (95% confidence interval €217 to €515). Salpingotomy resulted in a marginally higher ongoing pregnancy rate by natural conception compared with salpingectomy leading to an incremental cost-effectiveness ratio €40 982 (95% confidence interval -€130 319 to €145 491) per ongoing pregnancy. Since salpingotomy resulted in more additional treatments for persistent trophoblast and interventions for repeat ectopic pregnancy, the incremental cost-effectiveness ratio was not informative. LIMITATIONS, REASONS FOR CAUTION: Costs of any subsequent IVF cycles were not included in this analysis. The analysis was limited to the perspective of the hospital. WIDER IMPLICATIONS OF THE FINDINGS: However, a small treatment benefit of salpingotomy might be enough to cover the costs of subsequent IVF. This uncertainty should be incorporated in shared decision-making. Whether salpingotomy should be offered depends on society's willingness to pay for an additional child. STUDY FUNDING/COMPETING INTERESTS: Netherlands Organisation for Health Research and Development, Region Västra Götaland Health & Medical Care Committee. TRIAL REGISTRATION NUMBER: ISRCTN37002267.


Assuntos
Análise Custo-Benefício , Complicações Pós-Operatórias/economia , Gravidez Tubária/cirurgia , Salpingectomia/efeitos adversos , Salpingectomia/economia , Salpingostomia/efeitos adversos , Salpingostomia/economia , Adulto , Feminino , Humanos , Gravidez
10.
Ultrasound Obstet Gynecol ; 46(3): 367-75, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25586877

RESUMO

OBJECTIVE: To describe the ultrasound findings and natural history of pregnancies implanted within or on Cesarean section scars in the first trimester of pregnancy. METHODS: This was a prospective observational study of 10 women diagnosed with a pregnancy implanted in or on a Cesarean section scar in the first trimester, who declined medical intervention because of their desire to continue the pregnancy. The study population comprised women at < 12 weeks' gestation who were seen in our early pregnancy unit between January 2011 and September 2013. Nine women were followed up by serial ultrasound examinations and had detailed care plans for delivery at King's College Hospital (KCH). One woman was followed up and delivered at another teaching hospital. The first-trimester ultrasound findings were compared with the clinical outcome of the pregnancy. RESULTS: The nine patients who were followed up at KCH developed ultrasound findings of morbidly adherent placenta (MAP) in the second and third trimesters. All 10 patients were diagnosed with MAP at the time of delivery by Cesarean section. The gestational age at delivery ranged from 26 to 38 weeks. The uterus was conserved in five patients, and Cesarean hysterectomy was performed in the remaining five. All three women with complete implantation of the gestational sac within the scar and two of three cases with placental lakes in the first trimester had hysterectomies. The two cases with bulging of the gestational sac out of the uterine contour had a preterm emergency hysterectomy due to placenta percreta. Histology confirmed placenta accreta in the five hysterectomy specimens. There were no fetal or neonatal complications. CONCLUSIONS: Implantation of a pregnancy on or in a Cesarean section scar is a precursor of MAP; however, the degree of morbidity associated with this implantation is variable and difficult to predict based on first-trimester ultrasound findings only. The assessment of ongoing pregnancies implanted in Cesarean scars is most beneficial when performed between 7 and 9 weeks' gestation. Complete implantation within the myometrial defect, bulging of the trophoblast from the uterine contour and large placental lakes in the first trimester are ultrasound findings that may predict severe placenta accreta or percreta and consequently a poor outcome.


Assuntos
Cesárea , Cicatriz , Doenças Placentárias/etiologia , Complicações Pós-Operatórias , Primeiro Trimestre da Gravidez , Gravidez Ectópica/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Cicatriz/etiologia , Feminino , Seguimentos , Humanos , Doenças Placentárias/diagnóstico por imagem , Doenças Placentárias/cirurgia , Gravidez , Resultado da Gravidez , Gravidez Ectópica/cirurgia , Estudos Prospectivos
12.
Ultrasound Obstet Gynecol ; 43(3): 317-21, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23868814

RESUMO

OBJECTIVE: To review the success rate of expectant management in a series of interstitial pregnancies. METHODS: We identified all women with an ultrasound diagnosis of interstitial pregnancy seen within a 9-year period (January 2004 to April 2013). The clinical history, ultrasound findings and biochemical results were reviewed. The outcome of all interstitial pregnancies managed conservatively was recorded. Treatment was considered as successful when the serum ß-human chorionic gonadotropin (ß-hCG) level declined below 20 IU/L without the need for further intervention. RESULTS: A total of 48 interstitial pregnancies were diagnosed during the study period. Surgery was the first-line treatment in nine (18.8%) cases. Thirty-eight (79.2%) women were offered non-surgical management: 19 (39.6%) had methotrexate (MTX) and 19 (39.6%) were managed expectantly. One (2.1%) woman returned to her local hospital following diagnosis and we were unable to obtain any follow-up information regarding her care. The median initial serum ß-hCG level and ectopic size were not significantly different between any of the groups according to initial treatment. The overall success rate of expectant management was 89.5%. There were no cases of ectopic rupture in this group. Length of follow-up ranged from 7 to 141 days with a median duration of follow-up of 50.6 days. CONCLUSION: Our data show that expectant management is an option for selected women with non-viable interstitial pregnancies and declining serum ß-hCG levels, irrespective of ectopic mass size and initial serum ß-hCG levels.


Assuntos
Abortivos não Esteroides/uso terapêutico , Aborto Terapêutico/métodos , Gonadotropina Coriônica Humana Subunidade beta/sangue , Metotrexato/uso terapêutico , Gravidez Ectópica/terapia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Gravidez , Gravidez Ectópica/sangue , Gravidez Ectópica/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia Pré-Natal
13.
Clin Anat ; 27(2): 234-40, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23959791

RESUMO

Biomechanical models predict that recruitment of gluteus maximus (GMax) will exert a compressive force across the sacroiliac joint (SIJ), yet this muscle requires morphologic assessment. The aims of this study were to document GMax's proximal attachments and assess their capacity to generate forces including compressive force at the SIJ. In 11 embalmed cadaver limbs, attachments of GMax crossing the SIJ were dissected and their fascicle orientation, length and attachment volume documented. The physiological cross-sectional area (PCSA) of each attachment was calculated along with its estimated maximum force at the SIJ and lumbar spine. GMax fascicles originated from the gluteus medius fascia, ilium, thoracolumbar fascia, erector spinae aponeurosis, sacrum, coccyx, dorsal sacroiliac and sacrotuberous ligaments in all specimens. Their mean fascicle orientation ranged from 32 to 45° below horizontal and mean length from 11 to 18 cm. The mean total PCSA of GMax was 26 cm(2) (range 16-36), of which 70% crossed the SIJ. The average maximum force predicted to be generated by GMax's total attachments crossing each SIJ was 891 N (range 572-1,215), of which 70% (702 N: range 450-1,009) could act perpendicular to the plane of the SIJ. The capacity of GMax to generate an extensor moment at lower lumbar segments was estimated at 4 Nm (range 2-9.5). GMax may generate compressive forces at the SIJ through its bony and fibrous attachments. These may assist effective load transfer between lower limbs and trunk.


Assuntos
Fáscia/anatomia & histologia , Quadril/anatomia & histologia , Vértebras Lombares/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Articulação Sacroilíaca/anatomia & histologia , Vértebras Torácicas/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Cadáver , Fáscia/fisiologia , Feminino , Quadril/fisiologia , Humanos , Vértebras Lombares/fisiologia , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos , Modelos Biológicos , Músculo Esquelético/fisiologia , Articulação Sacroilíaca/fisiologia , Vértebras Torácicas/fisiologia
14.
Br J Cancer ; 109(7): 1895-8, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24002589

RESUMO

BACKGROUND: A hormonal aetiology is one explanation for the lower incidence of myeloid leukaemia in women compared with men. METHODS: In this population-based case-control study, we evaluated associations between exogenous hormone use and reproductive history and myeloid leukaemia, overall and by disease subtype. RESULTS: We observed a suggestive association between oral contraceptive use and acute myeloid leukaemia (odds ratio=0.55, 95% confidence interval=0.32-0.96). Hormone replacement therapy and reproductive factors were not associated with risk. CONCLUSION: Despite the biological plausibility for a role of oestrogen in leukaemogenesis, other aetiologic factors are likely to explain the differing incidence rates in males and females.


Assuntos
Anticoncepcionais Orais/efeitos adversos , Estrogênios/efeitos adversos , Terapia de Reposição Hormonal , Leucemia Mieloide/etiologia , História Reprodutiva , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Fatores de Risco , Adulto Jovem
15.
Rapid Commun Mass Spectrom ; 27(15): 1769-77, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23821570

RESUMO

RATIONALE: Conventionally, myofibrillar protein synthesis is measured over time periods of hours. In clinical studies, interventions occur over weeks. Functional measures over such periods may be more representative. We aimed to develop a novel method to determine myofibrillar protein fractional synthetic rate (FSR) to estimate habitual rates, while avoiding intravenous tracer infusions. METHODS: Four healthy males were given 100 g water enriched to 70 Atom % with (2)H2O as a single oral bolus. Vastus-lateralis needle biopsies were performed and plasma samples collected, 3-13 days post-dose. (2)H enrichment in body water was measured in plasma using continuous flow isotope ratio mass spectrometry (IRMS). Myofibrillar protein was isolated from muscle biopsies and acid hydrolysed. (2)H enrichment of protein-bound and plasma-free alanine was measured by gas chromatography (GC)/pyrolysis/IRMS. Myofibrillar protein FSR was calculated (% day(-1)). RESULTS: The tracer bolus raised the initial enrichment of body water to 1514 ppm (2)H excess. Water elimination followed a simple exponential. The average elimination half-time was 8.3 days. Plasma alanine, labelled during de novo synthesis, followed the same elimination kinetics as water. The weighted average myofibrillar protein FSR from the four subjects was 1.38 % day(-1) (range, 1.0-1.9 % day(-1) ). CONCLUSIONS: Myofibrillar protein FSR was measured in free-living healthy individuals over 3-13 days. Using a single oral (2)H2O bolus, endogenous labelling of alanine occurred in a predictable manner giving estimates of synthesis comparable with published values. Furthermore, the protocol does not compromise the ability to measure other important metabolic processes such as total energy expenditure.


Assuntos
Cromatografia Gasosa/métodos , Espectrometria de Massas/métodos , Proteínas Musculares/química , Biossíntese de Proteínas , Adulto , Humanos , Cinética , Masculino , Proteínas Musculares/sangue , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Miofibrilas/química , Miofibrilas/genética , Miofibrilas/metabolismo
16.
Ultrasound Obstet Gynecol ; 42(5): 585-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23733598

RESUMO

OBJECTIVE: To determine the clinical significance of a chorionic bump diagnosed by ultrasound in women attending an early pregnancy unit in a teaching hospital. METHODS: This was a retrospective case-control study over an 8-year period (2003-2010). Cases of chorionic bump were identified by searching our early pregnancy database and were matched to controls in a ratio of 1:3. The primary outcome measure was miscarriage vs ongoing pregnancy. Secondary outcomes were gestational age at delivery and the presence or absence of fetal abnormality. RESULTS: A total of 37 798 pregnancies were examined over the study period and 57 pregnancies with a chorionic bump were identified, giving an estimated prevalence of 1.5 per 1000 pregnancies (0.15%; 95% CI, 0.01-0.73%). Of the 52 women with follow-up data, 20 (38.5%; 95% CI, 26.4-52.1%) miscarried vs 31/151 (20.5%; 95% CI, 14.8-27.7%) in the control group (P = 0.01). There were four second-trimester miscarriages in the study group and none in the controls (P < 0.01). Out of 52 pregnancies in the study group there were 32 live births (62%; 95% CI, 47.9-73.6%) vs 118/151 (78%; 95% CI, 70.9-84.0%) in the control group (P = 0.02). There were no differences in preterm delivery rates or fetal anomalies. No significant relationship was found between size of the bump or location in relation to the umbilical cord insertion and risk of miscarriage. CONCLUSIONS: Women presenting to early pregnancy units with a chorionic bump discovered at first-trimester ultrasound examination had approximately double the risk of miscarriage compared with matched controls, the difference being due to a greater number of miscarriages during the second trimester of pregnancy.


Assuntos
Córion/diagnóstico por imagem , Feto/anormalidades , Idade Gestacional , Saco Gestacional/diagnóstico por imagem , Resultado da Gravidez , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-Natal
17.
Br J Cancer ; 107(1): 143-9, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22677901

RESUMO

BACKGROUND: Degradation of the extracellular matrix is fundamental to tumour development, invasion and metastasis. Several protease families have been implicated in the development of a broad range of tumour types, including oesophago-gastric (OG) adenocarcinoma. The aim of this study was to analyse the expression levels of all core members of the cancer degradome in OG adenocarcinoma and to investigate the relationship between expression levels and tumour/patient variables associated with poor prognosis. METHODS: Comprehensive expression profiling of the protease families (matrix metalloproteinases (MMPs), members of the ADAM metalloproteinase-disintegrin family (ADAMs)), their inhibitors (tissue inhibitors of metalloproteinase), and molecules involved in the c-Met signalling pathway, was performed using quantitative real-time reverse transcription polymerase chain reaction in a cohort of matched malignant and benign peri-tumoural OG tissue (n=25 patients). Data were analysed with respect to clinico-pathological variables (tumour stage and grade, age, sex and pre-operative plasma C-reactive protein level). RESULTS: Gene expression of MMP1, 3, 7, 9, 10, 11, 12, 16 and 24 was upregulated by factors >4-fold in OG adenocarcinoma samples compared with matched benign tissue (P<0.01). Expression of ADAM8 and ADAM15 correlated significantly with tumour stage (P=0.048 and P=0.044), and ADAM12 expression correlated with tumour grade (P=0.011). CONCLUSION: This study represents the first comprehensive quantitative analysis of the expression of proteases and their inhibitors in human OG adenocarcinoma. These findings implicate elevated ADAM8, 12 and 15 mRNA expression as potential prognostic molecular markers.


Assuntos
Proteínas ADAM/genética , Adenocarcinoma/genética , Proteína C-Reativa/metabolismo , Neoplasias Esofágicas/genética , Metaloproteinases da Matriz/genética , Neoplasias Gástricas/genética , Inibidores Teciduais de Metaloproteinases/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
18.
Sci Rep ; 12(1): 13178, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915112

RESUMO

We present observations of the high momentum tail in expanding Bose-Einstein condensates of metastable Helium atoms released from a harmonic trap. The far-field density profile exhibits features that support identification of the tails of the momentum distribution as originating in the in-situ quantum depletion prior to release. Thus, we corroborate recent observations of slowly-decaying tails in the far-field beyond the thermal component. This observation is in conflict with the hydrodynamic theory, which predicts that the in-situ depletion does not survive when atoms are released from a trap. Indeed, the depleted tails even appear stronger in the far-field than expected before release, and we discuss the challenges of interpreting this in terms of the Tan contact in the trapped gas. In complement to these observations, full quantum simulations of the experiment show that, under the right conditions, the depletion can persist into the far field after expansion. Moreover, the simulations provide mechanisms for survival and for the the large-momentum tails to appear stronger after expansion due to an acceleration of the depleted atoms by the mean-field potential. However, while in qualitative agreement, the final depletion observed in the experiment is much larger than in the simulation.

19.
Science ; 376(6589): 199-203, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35389780

RESUMO

Despite quantum electrodynamics (QED) being one of the most stringently tested theories underpinning modern physics, recent precision atomic spectroscopy measurements have uncovered several small discrepancies between experiment and theory. One particularly powerful experimental observable that tests QED independently of traditional energy level measurements is the "tune-out" frequency, where the dynamic polarizability vanishes and the atom does not interact with applied laser light. In this work, we measure the tune-out frequency for the 23S1 state of helium between transitions to the 23P and 33P manifolds and compare it with new theoretical QED calculations. The experimentally determined value of 725,736,700(260) megahertz differs from theory [725,736,252(9) megahertz] by 1.7 times the measurement uncertainty and resolves both the QED contributions and retardation corrections.

20.
Br J Cancer ; 104(3): 532-6, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21157452

RESUMO

BACKGROUND: Infant leukaemia is likely initiated in utero. METHODS: We examined whether analgesic use during pregnancy was associated with risk by completing telephone interviews of the mothers of 441 infant leukaemia cases and 323 frequency-matched controls, using unconditional logistic regression. RESULTS: With the exception of a reduced risk for infant acute myeloid leukaemias with non-aspirin non-steroidal anti-inflammatory drugs (NSAID) use early in pregnancy (odds ratios=0.60; confidence intervals: 0.37-0.97), no statistically significant associations were observed for aspirin, non-aspirin NSAIDs, or acetaminophen use in early pregnancy or after knowledge of pregnancy. CONCLUSION: Overall, analgesic use during pregnancy was not significantly associated with the risk of infant leukaemia.


Assuntos
Analgésicos/efeitos adversos , Leucemia/etiologia , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Analgésicos/uso terapêutico , Anti-Inflamatórios não Esteroides , Aspirina , Feminino , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
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