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1.
BJOG ; 131(4): 472-482, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37718558

RESUMEN

OBJECTIVES: To investigate the association and the potential value of prelabour fetal heart rate short-term variability (STV) determined by computerised cardiotocography (cCTG) and maternal and fetal Doppler in predicting labour outcomes. DESIGN: Prospective cohort study. SETTING: The Prince of Wales Hospital, a tertiary maternity unit, in Hong Kong SAR. POPULATION: Women with a term singleton pregnancy in latent phase of labour or before labour induction were recruited during May 2019-November 2021. METHODS: Prelabour ultrasonographic assessment of fetal growth, Doppler velocimetry and prelabour cCTG monitoring including Dawes-Redman CTG analysis were registered shortly before induction of labour or during the latent phase of spontaneous labour. MAIN OUTCOME MEASURES: Umbilical cord arterial pH, emergency delivery due to pathological CTG during labour and neonatal intensive care unit (NICU)/special care baby unit (SCBU) admission. RESULTS: Of the 470 pregnant women invited to participate in the study, 440 women provided informed consent and a total of 400 participants were included for further analysis. Thirty-four (8.5%) participants underwent emergency delivery for pathological CTG during labour. A total of 6 (1.50%) and 148 (37.00%) newborns required NICU and SCBU admission, respectively. Middle cerebral artery pulsatility index (MCA-PI) and MCA-PI z-score were significantly lower in pregnancies that required emergency delivery for pathological CTG during labour compared with those that did not (1.23 [1.07-1.40] versus 1.40 [1.22-1.64], p = 0.002; and 0.55 ± 1.07 vs. 0.12 ± 1.06), p = 0.049]. This study demonstrated a weakly positive correlation between umbilical cord arterial pH and prelabour log10 STV (r = 0.107, p = 0.035) and the regression analyses revealed that the contributing factors for umbilical cord arterial pH were smoking (p = 0.006) and prelabour log10 STV (p = 0.025). CONCLUSIONS: In pregnant women admitted in latent phase of labour or for induction of labour at term, prelabour cCTG STV had a weakly positive association with umbilical cord arterial pH but was not predictive of emergency delivery due to pathological CTG during labour.


Asunto(s)
Cardiotocografía , Trabajo de Parto , Embarazo , Femenino , Recién Nacido , Humanos , Estudios Prospectivos , Feto , Atención Prenatal
2.
Magn Reson Med ; 89(5): 1809-1824, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36511247

RESUMEN

PURPOSE: We investigated the correlation, reproducibility, and effect of white matter fiber orientation for three myelin-sensitive MRI techniques: magnetization transfer ratio (MTR), inhomogeneous magnetization transfer ratio (ihMTR), and gradient and spin echo-derived myelin water fraction (MWF). METHODS: We measured the three metrics in 17 white and three deep grey matter regions in 17 healthy adults at 3 T. RESULTS: We found a strong correlation between ihMTR and MTR (r = 0.70, p < 0.001) and ihMTR and MWF (r = 0.79, p < 0.001), and a weaker correlation between MTR and MWF (r = 0.54, p < 0.001). The dynamic range in white matter was greatest for MWF (2.0%-27.5%), followed by MTR (14.4%-23.2%) and then ihMTR (1.2%-5.4%). The average scan-rescan coefficient of variation for white matter regions was 0.6% MTR, 0.3% ihMTR, and 0.7% MWF in metric units; however, when adjusted by the dynamic range, these became 6.3%, 6.1% and 2.8%, respectively. All three metrics varied with fiber direction: MWF and ihMTR were lower in white matter fibers perpendicular to B0 by 6% and 1%, respectively, compared with those parallel, whereas MTR was lower by 0.5% at about 40°, with the highest values at 90°. However, separating the apparent orientation dependence by white matter region revealed large dissimilarities in the trends, suggesting that real differences in myelination between regions are confounding the apparent orientation dependence measured using this method. CONCLUSION: The strong correlation between ihMTR and MWF suggests that these techniques are measuring the same myelination; however, the larger dynamic range of MWF may provide more power to detect small differences in myelin.


Asunto(s)
Vaina de Mielina , Sustancia Blanca , Humanos , Adulto , Reproducibilidad de los Resultados , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen , Agua , Biomarcadores
3.
Waste Manag Res ; 41(1): 3-17, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35652693

RESUMEN

Healthcare generates large amounts of waste, harming both environmental and human health. Waste audits are the standard method for measuring and characterizing waste. This is a systematic review of healthcare waste audits, describing their methods and informing more standardized auditing and reporting. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched MEDLINE, Embase, Inspec, Scopus and Web of Science Core Collection databases for published studies involving direct measurement of waste in medical facilities. We screened 2398 studies, identifying 156 studies for inclusion from 37 countries. Most were conducted to improve local waste sorting policies or practices, with fewer to inform policy development, increase waste diversion or reduce costs. Measurement was quantified mostly by weighing waste, with many also counting items or using interviews or surveys to compile data. Studies spanned single procedures, departments and hospitals, and multiple hospitals or health systems. Waste categories varied, with most including municipal solid waste or biohazardous waste, and others including sharps, recycling and other wastes. There were significant differences in methods and results between high- and low-income countries. The number of healthcare waste audits published has been increasing, with variable quality and general methodologic inconsistency. A greater emphasis on consistent performance and reporting standards would improve the quality, comparability and usefulness of healthcare waste audits.


Asunto(s)
Atención a la Salud , Hospitales , Humanos
4.
Curr Oncol Rep ; 24(10): 1363-1372, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35639330

RESUMEN

BACKGROUND: Many cancer patients use complementary, alternative, and integrative medicine (CAIM) to improve their psychological and functional health. However, there is little known about the extent of CAIM information and services provided on oncology hospital websites. METHODS: This study reviewed public-facing websites to determine the degree of CAIM information provided and services offered by the world's leading cancer hospitals in 2021; this ranking was informed by a large survey of medical professionals led by Newsweek and Statista. Nine authors extracted data from hospital websites individually and in triplicate, prior to meeting to revise data extractions. Data analysis was then performed by two authors to determine how many hospitals provided CAIM descriptions and offered CAIM services, and the extent of CAIM information provided. RESULTS: A total of 131 hospitals were included in this study. Of the eligible hospitals, 50.38% (n = 66) provided a theoretical description of CAIM; 48.09% (n = 63) provided a description of one or more CAIM therapies; 63.36% (n = 83) offered one or more CAIM therapies to cancer patients. The most common therapies described were the same as the most common therapies offered. These therapies are massage, special foods and diets, acupuncture, meditation, yoga, and creative outlets. While CAIM therapies were commonly offered, information surrounding the benefits and side effects associated with these therapies varied. CONCLUSIONS: Due to the lack of CAIM standardization worldwide, there is a need for increased CAIM information provision on hospital websites to better inform and empower patients to make well-informed decisions about their health.


Asunto(s)
Terapias Complementarias , Medicina Integrativa , Neoplasias , Hospitales , Humanos , Oncología Médica , Neoplasias/terapia
5.
J Physiol ; 596(16): 3531-3552, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29873405

RESUMEN

KEY POINTS: In the bladder suburothelial microvasculature, pericytes in different microvascular segments develop spontaneous Ca2+ transients with or without associated constrictions. Spontaneous Ca2+ transients in pericytes of all microvascular segments primarily rely on the cycles of Ca2+ uptake and release by the sarco- and endoplasmic reticulum. The synchrony of spontaneous Ca2+ transients in capillary pericytes exclusively relies on the spread of depolarizations resulting from the opening of Ca2+ -activated chloride channels (CaCCs) via gap junctions. CaCC-dependent depolarizations further activate L-type voltage-dependent Ca2+ channels as required for the synchrony of Ca2+ transients in pericytes of pre-capillary arterioles, post-capillary venules and venules. Capillary pericytes may drive spontaneous Ca2+ transients in pericytes within the suburothelial microvascular network by sending CaCC-dependent depolarizations via gap junctions. ABSTRACT: Mural cells in the microvasculature of visceral organs develop spontaneous Ca2+ transients. However, the mechanisms underlying the integration of these Ca2+ transients within a microvascular unit remain to be clarified. In the present study, the origin of spontaneous Ca2+ transients and their propagation in the bladder suburothelial microvasculature were explored. Cal-520 fluorescence Ca2+ imaging and immunohistochemistry were carried out on mural cells using mice expressing red fluorescent protein (DsRed) under control of the NG2 promotor. NG2(+) pericytes in both pre-capillary arterioles (PCAs) and capillaries developed synchronous spontaneous Ca2+ transients. By contrast, although NG2-DsRed also labelled arteriolar smooth muscle cells, these cells remained quiescent. Both NG2(+) pericytes in post-capillary venules (PCVs) and NG2(-) venular pericytes exhibited propagated Ca2+ transients. L-type voltage-dependent Ca2+ channel (LVDCC) blockade with nifedipine prevented Ca2+ transients or disrupted their synchrony in PCA, PCV and venular pericytes without dis-synchronizing Ca2+ transients in capillary pericytes. Blockade of gap junctions with carbenoxolone or Ca2+ -activated chloride channels (CaCCs) with 4,4'-diisothiocyanato-2,2'-stilbenedisulphonic acid disodium salt prevented Ca2+ transients in PCA and venular pericytes and disrupted the synchrony of Ca2+ transients in capillary and PCV pericytes. Spontaneous Ca2+ transients in pericytes of all microvascular segments were abolished or suppressed by cyclopiazonic acid, caffeine or tetracaine. The synchrony of Ca2+ transients in capillary pericytes arising from spontaneous Ca2+ release from the sarco- and endoplasmic reticulum appears to rely exclusively on CaCC activation, whereas subsequent LVDCC activation is required for the synchrony of Ca2+ transients in pericytes of other microvascular segments. Capillary pericytes may drive spontaneous activity in the suburothelial microvascular unit to facilitate capillary perfusion.


Asunto(s)
Señalización del Calcio , Calcio/metabolismo , Capilares/fisiología , Canales de Cloruro/metabolismo , Microvasos/fisiología , Pericitos/fisiología , Vejiga Urinaria/fisiología , Animales , Femenino , Uniones Comunicantes , Masculino , Ratones , Vejiga Urinaria/irrigación sanguínea , Venas/fisiología
7.
Neurourol Urodyn ; 34(5): 482-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24436088

RESUMEN

AIMS: To examine the effects of the α1A -adrenoceptor antagonist, tamsulosin, on spontaneous contractile and electrical activity in the guinea-pig prostate gland. METHODS: The effects of tamsulosin (0.1 and 0.3 nM) were investigated in adult and ageing male guinea pig prostate glands using conventional tension recording and electrophysiological intracellular microelectrode recording techniques. RESULTS: Tamsulosin reduced spontaneous activity, and had different age-dependent effects on adult and ageing guinea pigs at different concentrations. 0.1 nM tamsulosin caused a significantly greater reduction of spontaneous contractile and electrical activity in ageing guinea pigs in comparison to adult guinea pigs. In contrast, 0.3 nM tamsulosin had a significantly greater reduction of spontaneous contractile and electrical activity in adult guinea pigs in comparison to ageing guinea pigs. CONCLUSIONS: This study demonstrates that tamsulosin can modulate spontaneous myogenic stromal contractility and the underlying spontaneous electrical activity; tamsulosin does not block spontaneous activity. This reduction in spontaneous activity suggests that downstream cellular mechanisms underlying smooth muscle tone are being targeted, and these may represent novel therapeutic targets to better treat benign prostatic hyperplasia.


Asunto(s)
Antagonistas de Receptores Adrenérgicos alfa 1/farmacología , Envejecimiento , Potenciales de la Membrana/efectos de los fármacos , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Próstata/efectos de los fármacos , Sulfonamidas/farmacología , Animales , Fenómenos Electrofisiológicos/efectos de los fármacos , Cobayas , Masculino , Tamsulosina
8.
J Urol ; 192(4): 1286-92, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24641914

RESUMEN

PURPOSE: Spontaneous phasic contractions of the guinea pig prostate stroma result from the generation of slow waves that appear to primarily rely on spontaneous Ca(2+) release from the endoplasmic/sarcoplasmic reticulum and subsequent opening of Ca(2+) activated chloride channels. We investigated voltage dependent mechanisms in the regulation of slow wave frequency. MATERIALS AND METHODS: Changes in membrane potential were recorded using conventional intracellular recording techniques while simultaneously measuring the isometric tension of guinea pig prostate lobes. Fluorescence immunohistochemistry was done to determine the cellular composition of the prostate stroma. RESULTS: Depolarization induced by high K(+) solution, K(+) free solution or outward current injection was associated with increased slow wave frequency. In contrast, hyperpolarization induced by the re-addition of K(+), adenosine triphosphate sensitive K(+) channel openers or inward current injection prevented slow wave generation. K(+) channel openers induced hyperpolarization and the cessation of slow waves was reversed by glibenclamide (10 µM). Nifedipine (1 to 10 µM) shortened the duration of slow waves and pacemaker potentials but often failed to prevent their generation and associated contractions. Subsequently Ni(2+) (100 µM) or mibefradil (1 µM) largely suppressed slow waves and abolished residual contractions. Immunohistochemistry revealed small interconnected smooth muscle bundles as well as vimentin positive interstitial cells but failed to show a network of Kit positive interstitial cells. CONCLUSIONS: Prostate slow wave frequency is voltage dependent due to the significant contribution of L-type and T-type Ca(2+) channels. Prostate slow waves may arise from cooperation between spontaneous Ca(2+) release from internal stores and plasmalemmal voltage dependent Ca(2+) channels.


Asunto(s)
Canales de Calcio/metabolismo , Señalización del Calcio , Células Intersticiales de Cajal/fisiología , Próstata/metabolismo , Animales , Cobayas , Inmunohistoquímica , Masculino , Potenciales de la Membrana , Próstata/citología
9.
BMJ Open ; 14(5): e083724, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719284

RESUMEN

INTRODUCTION: The rapid growth of the ageing population underscores the critical need for dementia care training among care providers. Innovative virtual reality (VR) technology has created opportunities to improve dementia care training. This scoping review will specifically focus on the barriers, facilitators and impacts of implementing fully immersive VR training for dementia care among staff in long-term care (LTC) settings. METHODS AND ANALYSIS: We will follow the Joanna Briggs Institute's scoping review methodology to ensure scientific rigour. We will collect literature of all languages with abstracts in English from CINAHL, Medline, Scopus, Embase, Web of Science and ProQuest database until 31 December 2023. Grey literature from Google Scholar and AgeWell websites will be included. Inclusion criteria encompass papers involving paid staff (Population), fully immersive VR training on dementia care (Concept) and LTC settings (Context). Literature referring only to non-paid caregivers, non-fully immersive VR or other chronic diseases will be excluded. Literature screening, data extraction and analysis will be conducted by two reviewers separately. We will present a narrative summary with a charting table on the main findings. ETHICS AND DISSEMINATION: This work does not require ethics approval, given the public data availability for this scoping review. Through a comprehensive overview of the current evidence regarding impacts, barriers and facilitators on this topic, potential insights and practical recommendations will be generated to support the implementation of VR training to enhance staff competence in LTC settings. The findings will be presented in a journal article and shared with practitioners on the frontline.


Asunto(s)
Demencia , Cuidados a Largo Plazo , Realidad Virtual , Humanos , Demencia/terapia , Personal de Salud/educación
10.
J Urol ; 189(3): 1147-54, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23000000

RESUMEN

PURPOSE: Men with benign prostatic hyperplasia commonly experience irritative lower urinary tract symptoms, which are due at least in part to enhanced prostatic smooth muscle tone. To provide some insight into the changes that occur in prostatic contractility with age, we examined the contribution of rho-kinase dependent Ca(2+) sensitization in neurogenic and spontaneous contractions of young and aging guinea pig prostates. MATERIALS AND METHODS: We used conventional tension recording and electrophysiological intracellular microelectrode recording techniques. RESULTS: The Rho-kinase inhibitor Y-27632 (10 and 100 µM) significantly inhibited electrical field stimulated evoked (neurogenic) contractions in the guinea pig prostate in a dose dependent manner. In addition, Y-27632 (1 and 10 µM) similarly suppressed tetrodotoxin insensitive spontaneous contractions in dose dependent fashion. While Y-27632 at 10 µM decreased spontaneous contractions of young and aging guinea pig prostates, as evidenced by a significant decrease in the AUC, there was no significant difference in the degree of inhibition between the 2 age groups. In contrast to contractile activity, Y-27632 did not affect the generation or modulation of spontaneous slow wave electrical activity, which underlies spontaneous contractions. CONCLUSIONS: There are strong indicators that Rho-kinase signaling pathways have a significant role in prostatic smooth muscle contractility, most likely independent of cytosolic Ca(2+) levels. Features of the rho-kinase pathway may well represent alternative, novel future therapeutic targets to reduce prostatic contractility, thereby alleviating the lower urinary tract symptoms arising from benign prostatic hyperplasia.


Asunto(s)
Contracción Muscular/fisiología , Músculo Liso/enzimología , Próstata/enzimología , Quinasas Asociadas a rho/metabolismo , Animales , Cobayas , Masculino , Próstata/fisiología , Transducción de Señal
11.
BJU Int ; 112(4): E398-405, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23879919

RESUMEN

UNLABELLED: What's known on the subject? and what does the study add?: Several studies have examined the functional role of tyrosine kinase receptors in the generation of spontaneous activity in various segments of the gastrointestinal and urogenital tracts through the application of its inhibitor, imatinib mesylate (Glivec®), but results are fairly inconsistent. This is the first study detailing the effects of imatinib mesylate on the spontaneous activity in the young and ageing prostate gland. As spontaneous electrical activity underlies the spontaneous rhythmic prostatic contractions that occur at rest, elucidating the mechanisms involved in the regulation of the spontaneous electrical activity and the resultant phasic contractions could conceivably lead to the identification of better targets and the development of more specific therapeutic agents to treat prostate conditions. OBJECTIVE: To investigate the effect of imatinib mesylate, a tyrosine kinase receptor inhibitor, in the generation of spontaneous electrical and contractile activity in the young and ageing guinea-pig prostate. MATERIALS AND METHODS: Standard tension and intracellular recording were used to measure spontaneous contractions and slow waves, respectively from the guinea-pig prostate at varying concentrations of imatinib mesylate (1-50 µm). RESULTS: Imatinib mesylate (1-10 µm), did not significantly affect slow waves recorded in the prostate of both age groups but at 50 µm, the amplitude of slow waves from the ageing guinea-pig prostate was significantly reduced (P < 0.05, n = 5). In contrast, the amplitude of contractions across all concentrations in the young guinea-pig prostate was reduced to between 35% and 41% of control, while the frequency was reduced to 15.7% at 1 µm (n = 7), 49.8% at 5 µm (n = 10), 46.2% at 10 µm (n = 7) and 53.1% at 50 µm (n = 5). Similarly, imatinib mesylate attenuated the amplitude and slowed the frequency of contractions in ageing guinea-pigs to 5.15% and 3.3% at 1 µm (n = 6); 21.1% and 20.8% at 5 µm (n = 8); 58.4% and 8.8% at 10 µm (n = 11); 72.7% and 60% at 50 µm (n = 5). CONCLUSIONS: A significant reduction in contractions but persistence of slow waves suggests imatinib mesylate may affect the smooth muscle contractile mechanism. Imatinib mesylate also significantly reduced contractions in the prostates of younger guinea pigs more than older ones, which is consistent with the notion that the younger guinea-pig prostate is more reliant on the tyrosine-dependent pacemaker ability of interstitial cells of Cajal-like prostatic interstitial cells.


Asunto(s)
Benzamidas/farmacología , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Piperazinas/farmacología , Próstata/efectos de los fármacos , Próstata/fisiología , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Animales , Cobayas , Mesilato de Imatinib , Masculino
12.
BMC Public Health ; 13: 1004, 2013 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-24156496

RESUMEN

BACKGROUND: Heat-related illness (HRI) is an important cause of non-fatal illness and death in farmworkers. We sought to identify potential barriers to HRI prevention and treatment in Latino farmworkers. METHODS: We conducted three semi-structured focus group discussions with 35 Latino farmworkers in the Central Washington, USA area using participatory rural appraisal techniques. Interviews were audio taped and transcribed in Spanish. Three researchers reviewed and coded transcripts and field notes, and investigator triangulation was used to identify relevant themes and quotes. RESULTS: Although the majority of participants in our study reported never receiving formal HRI training, most participants were aware that extreme heat can cause illness and were able to accurately describe HRI symptoms, risk factors, and certain prevention strategies. Four main observations regarding farmworkers' HRI-relevant beliefs and attitudes were identified: 1) farmworkers subscribe to varying degrees to the belief that cooling treatments should be avoided after heat exposure, with some believing that such treatments should be avoided after heat exposure, and others encouraging the use of such treatments; 2) the desire to lose weight may be reflected in behaviors that promote increased sweating; 3) highly caffeinated energy drinks are preferred to increase work efficiency and maintain alertness; and 4) the location of drinking water at work (e.g. next to restrooms) and whether water is clean, but not necessarily chemically-treated, are important considerations in deciding whether to drink the water provided at worksites. CONCLUSIONS: We identified potential barriers to HRI prevention and treatment related to hydration, certain HRI treatments, clothing use, and the desire to lose weight among Latino farmworkers. Strategies to address potential barriers to HRI prevention and treatment in this population may include engineering, administrative, and health education and health promotion strategies at individual, workplace, community, and societal levels. Although farmworkers in our study were able to describe HRI risk factors, reported practices were not necessarily consistent with reported knowledge. Further study of potential knowledge-behavior gaps may uncover opportunities for additional HRI prevention strategies. Farmworkers and employers should be included in the development and evaluation of interventions to prevent HRI.


Asunto(s)
Agricultura , Calor Extremo , Conocimientos, Actitudes y Práctica en Salud , Trastornos de Estrés por Calor , Hispánicos o Latinos , Enfermedades Profesionales/etnología , Salud Laboral , Adulto , Femenino , Fiebre/etnología , Fiebre/prevención & control , Fiebre/terapia , Grupos Focales , Educación en Salud , Trastornos de Estrés por Calor/etnología , Trastornos de Estrés por Calor/prevención & control , Trastornos de Estrés por Calor/terapia , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/prevención & control , Enfermedades Profesionales/terapia , Exposición Profesional/efectos adversos , Factores de Riesgo , Población Rural , Washingtón , Lugar de Trabajo , Adulto Joven
13.
JBJS Rev ; 11(3)2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36947638

RESUMEN

¼: The rapid increase in the use of electronic medical records (EMRs) has led to some unintended consequences that negatively affect physicians and their patients. ¼: The use of medical scribes may serve as a possible solution to some of the EMR-related concerns. ¼: Research has demonstrated an overall positive impact of having scribes on both physician and patient well-being, safety, and satisfaction. ¼: Adaptation of advances in technology, including remote and asynchronous scribing, use of face-mounted devices, voice recognition software, and applications of artificial intelligence may address some of the barriers to more traditional in-person scribes.


Asunto(s)
Procedimientos Ortopédicos , Ortopedia , Humanos , Inteligencia Artificial , Registros Electrónicos de Salud
14.
PLoS One ; 18(7): e0288289, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37428792

RESUMEN

BACKGROUND: International professional organizations recommend aspirin prophylaxis to women screened high risk for preterm preeclampsia (PE) in the first trimester. The UK Fetal Medicine Foundation (FMF) screening test for preterm PE using mean arterial pressure (MAP), uterine artery pulsatility index (UTPI) and placental growth factor (PlGF) was demonstrated to have lower detection rate (DR) in Asian population studies. Additional biomarkers are therefore needed in Asian women to improve screening DRs as a significant proportion of women with preterm and term PE are currently not identified. OBJECTIVES: To evaluate maternal serum inhibin-A at 11-13 weeks as an alternative to PlGF or as an additional biomarker within the FMF screening test for preterm PE. STUDY DESIGN: This is a nested case-control study using pregnancies initially screened at 11-13 weeks for preterm PE using the FMF triple test in a non-intervention study conducted between December 2016 and June 2018. Inhibin-A levels were retrospectively measured in 1,792 singleton pregnancies, 112 (1.7%) with PE matched for time of initial screening with 1,680 unaffected pregnancies. Inhibin-A levels were transformed to multiple of the expected median (MoM). The distribution of log10 inhibin-A MoM in PE and unaffected pregnancies and the association between log10 inhibin-A MoM and gestational age (GA) at delivery in PE were assessed. The screening performance determined by area under receiver operating characteristic curves (AUC) and detection rates (DRs) at a 10% fixed false positive rate (FPR), for preterm and term PE was determined. All risks for preterm and term PE were based on the FMF competing risk model and Bayes theorem. Differences in AUC (ΔAUC) between different biomarker combinations were compared using the Delong test. McNemar's test was used to assess the off-diagonal change in screening performance at a fixed 10% FPR after adding inhibin-A or replacing PlGF in the preterm PE adjusted risk estimation model. RESULTS: Inhibin-A levels in unaffected pregnancies were significantly dependent on GA, maternal age and weight and were lower in parous women with no previous history of PE. Mean log10 inhibin-A MoM in any-onset PE (p<0.001), preterm (p<0.001) and term PE (p = 0.015) pregnancies were all significantly higher than that of unaffected pregnancies. Log10 inhibin-A MoM was inversely but not significantly correlated (p = 0.165) with GA at delivery in PE pregnancies. Replacing PlGF with inhibin-A in the FMF triple test reduced AUC and DR from 0.859 and 64.86% to 0.837 and 54.05%, the ΔAUC was not statistically significant. AUC and DR when adding inhibin-A to the FMF triple test were 0.814, 54.05% and the -0.045 reduction in AUC was statistically significant (p = 0.001). At a fixed 10% FPR, replacing PlGF with inhibin-A identified 1 (2.7%) additional pregnancy but missed 5 (13.5%) pregnancies which subsequently developed preterm PE identified by the FMF triple test. Adding inhibin-A missed 4 (10.8%) pregnancies and did not identify any additional pregnancies with preterm PE. CONCLUSION: Replacing PlGF by inhibin-A or adding inhibin-A as an additional biomarker in and to the FMF triple screening test for preterm PE does not improve screening performance and will fail to identify pregnancies that are currently identified by the FMF triple test.


Asunto(s)
Preeclampsia , Embarazo , Recién Nacido , Femenino , Humanos , Primer Trimestre del Embarazo , Preeclampsia/epidemiología , Teorema de Bayes , Estudios de Casos y Controles , Estudios Retrospectivos , Factor de Crecimiento Placentario , Medición de Riesgo , Biomarcadores , Arteria Uterina/diagnóstico por imagen , Flujo Pulsátil
15.
J Matern Fetal Neonatal Med ; 35(7): 1318-1327, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32283958

RESUMEN

OBJECTIVES: To investigate (i) the association between pre-labor maternal-fetal Dopplers and fetal heart rate short-term variability (FHR STV) with arterial cord blood pH and (ii) the potential value of pre-labor maternal-fetal Dopplers, FHR STV and Dawes-Redman criteria in predicting composite neonatal morbidity at term in a cohort of unselected women. METHOD: A prospective study in 218 women with term singleton pregnancy in latent phase of labor or due to undergo induction of labor. Data on maternal characteristics, maternal-fetal Dopplers indices and computerized cardiotocography (CTG) findings of FHR STV and Dawes-Redman criteria were collected. Pearson correlation analysis was used to determine the relationship between maternal-fetal Dopplers and FHR STV and arterial cord blood pH. Logistic regression analysis was used to determine which factors amongst maternal characteristics, labor onset, indication of labor induction, estimated fetal weight (EFW), maternal-fetal Dopplers, FHR STV and Dawes-Redman criteria were significant predictors of composite neonatal morbidity and arterial cord blood pH less than 7.2. RESULT: Of the 218 cases, 12 (5.5%) women were delivered by emergency operative delivery for pathological CTG, and 42 babies (19.3%) had composite neonatal morbidities. Arterial cord blood pH was not associated with maternal-fetal Doppler indices and FHR STV, but rather it was associated with maternal age and body mass index. The composite neonatal morbidity and arterial cord blood pH less than 7.2 were not significantly associated with maternal characteristics, labor onset, indication of labor induction, pre-labor assessment of EFW, maternal-fetal Doppler indices, FHR STV and Dawes-Redman criteria by computerized CTG. CONCLUSION: In unselected women in latent phase of labor or undergoing induction of labor at term, admission maternal-fetal Doppler indices, FHR STV and Dawes-Redman criteria are not predictive of composite neonatal morbidity.


Asunto(s)
Cardiotocografía , Frecuencia Cardíaca Fetal , Trabajo de Parto , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal
16.
J Urol ; 186(6): 2478-86, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22019167

RESUMEN

PURPOSE: We investigated whether prostate interstitial cells generate spontaneous Ca(2+) oscillation, a proposed mechanism underlying pacemaker potentials to drive spontaneous activity in stromal smooth muscle cells. MATERIALS AND METHODS: Intracellular free Ca(2+) in portions of guinea pig prostate and freshly isolated, single prostate interstitial cells were visualized using fluo-4 Ca(2+) fluorescence. Spontaneous electrical activity was recorded in situ with intracellular microelectrodes. RESULTS: In whole tissue preparations spontaneous Ca(2+) flashes firing synchronously across all smooth muscle cells within the field of view resulted in muscle wall contractions. Nonpropagating Ca(2+) waves were also recorded in individual smooth muscle cells. Nifedipine (Sigma®) (1 µM) largely decreased or abolished these Ca(2+) flashes and suppressed slow wave discharge upon blockade of their superimposed action potentials. Isolated prostate interstitial cells were readily distinguished from smooth muscle cells by their spiky processes and lack of contraction during intracellular Ca(2+) increases. Prostate interstitial cells generated spontaneous Ca(2+) transients in the form of whole cell flashes, intracellular Ca(2+) waves or localized Ca(2+) sparks. All 3 Ca(2+) signals were abolished by nicardipine (1 µM), cyclopiazonic acid (10 µM), caffeine (Sigma) (10 mM) or extracellular Ca(2+) removal. CONCLUSIONS: Prostate interstitial cells generate spontaneous Ca(2+) transients that occur at a frequency comparable to Ca(2+) flashes in situ or slow waves relying on functional internal Ca(2+) stores. However, unlike other interstitial cells in the urinary tract, Ca(2+) influx through L-type Ca(2+) channels is fundamental to Ca(2+) transient firings in prostate interstitial cells. Thus, it is not possible to conclude that prostate interstitial cells are responsible for pacemaker potential generation.


Asunto(s)
Señalización del Calcio , Células Intersticiales de Cajal/fisiología , Próstata/metabolismo , Animales , Cobayas , Masculino
17.
Pharmacol Res ; 64(3): 235-41, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21536131

RESUMEN

This investigation aimed to examine the source of Ca(2+) mobilization that leads to the contractile response to either exogenously added histamine (1 µM-1mM) or electrical field stimulation (10Hz, 0.5ms, 60V). Removal of extracellular Ca(2+) by removal of Ca(2+) from the bathing medium reduced histamine (1mM) induced responses by 34% and responses induced by electrical field stimulation by 94%. Similarly, blockade of L-type Ca(2+) channels by nifedipine (1 µM) reduced histamine (1mM) induced responses by 43% and responses induced by electrical field stimulation by 77%. Application of cyclopiazonic acid (CPA) (10 µM) to inhibit Ca(2+) reuptake to the sarcoplasmic reticulum enhanced both histamine-induced and electrical field stimulation induced responses to a small degree, while the addition of the inosotol triphosphate (IP(3)) receptor antagonist, 2-aminophenoxyethane borane (2-APB) (100 µM) inhibited histamine induced responses by 70% and electrical field stimulation induced responses by 57%. Ryanodine (1 µM) did not affect contractile responses to either histamine or electrical field stimulation, either in the absence or presence of 2-APB (100 µM). During both histamine and electrical field stimulation induced contractions, prostate smooth muscle generates IP(3) receptor mediated Ca(2+) release in conjunction with Ca(2+) entry from the extracellular environment. Ryanodine receptors on the other hand, appear not to play a role in this physiological mechanism.


Asunto(s)
Calcio/metabolismo , Histamina/farmacología , Inositol 1,4,5-Trifosfato/metabolismo , Contracción Muscular/efectos de los fármacos , Próstata/fisiología , Animales , Boranos/farmacología , Bloqueadores de los Canales de Calcio/farmacología , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , Estimulación Eléctrica , Cobayas , Indoles/farmacología , Masculino , Nifedipino/farmacología , Próstata/metabolismo , Rianodina/farmacología
18.
Nano Lett ; 10(8): 3216-21, 2010 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-20698640

RESUMEN

A self-assembled magnetic recording medium was created using colloidal ferrimagnetic building blocks. Monodisperse cobalt ferrite nanoparticles (CoFe(2)O(4)) were synthesized using solution-based methods and then stabilized in solution using the amphiphilic diblock copolymer, poly(acrylic acid)-b-poly(styrene) (PAA-PS). The acid groups of the acrylate block bound the polymer to the nanoparticle surface via multivalent interactions, while the styrene block afforded the magnetic nanoparticle--polymer complex solubility in organic solvents. Moreover, the diblock copolymer improved the colloidal stability of the ferrimagnetic CoFe(2)O(4) nanoparticles by reducing the strong interparticle magnetic interactions, which typically caused the ferrimagnetic nanoparticles to irreversibly aggregate. The nanoparticle--polymer complex was spin-coated onto a silicon substrate to afford self-organized thin film arrays, with the interparticle spacing determined by the molecular weight of the diblock copolymer. The thin film composite was also exposed to an external magnetic field while simultaneously heated above the glass transition temperature of poly(styrene) to allow the nanoparticles to physically rotate to align their easy axes with the direction of the magnetic field. In order to demonstrate that this self-assembled ferrimagnet--polymer composite was suitable as a magnetic recording media, read/write cycles were demonstrated using a contact magnetic tester. This work provides a simple route to synthesizing stabilized ferrimagnetic nanocrystals that are suitable for developing magnetic recording media.

19.
Diagn Interv Radiol ; 27(4): 580-586, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34313246

RESUMEN

PURPOSE: We aimed to retrospectively correlate 18F-fluorodeoxyglucose (18F-FDG) metabolic activity with lumbar spine magnetic resonance imaging (MRI) findings and epidural steroid injection sites in patients with symptomatic degenerative disease of the lumbar spine. METHODS: A database search was conducted for patients receiving epidural injections <12 months after a positron emission tomography/computed tomography (PET/CT). Maximum standard uptake values (SUVmax) were measured at the facet joints, neural foramina, and spinal canal. Severity of facet arthrosis, disc degeneration, neuroforaminal, and canal stenosis was determined on MRI using previously described grading scales. Spearman rank coefficient assessed association between PET/CT FDG uptake and severity of MRI findings. The SUVmax was also compared with injection sites. RESULTS: Twenty-five patients were included, comprising MRI (n=19) and injection (n=22 patients; 18 interlaminar, 8 transforaminal) groups. Injections were performed an average of 2.6 months after PET/CT. The greatest SUVmax occurred at the L5-S1 spinal canal (mean SUVmax = 2.25). A statistically significant, positive correlation between uptake and grade of spinal canal stenosis was seen only at L4-L5 (r=0.60, p = 0.007). No other significant association was found with spinal canal or neuroforaminal stenosis, or grade of facet joint or disc degeneration. All patients reported symptomatic improvement after injections with mean pain score improvement of 4.4 on a 10-point scale (SD, 2.9). There was moderate agreement between sites of epidural injection and highest SUVmax (κ= 0.591, p < 0.001). CONCLUSION: 18F-FDG metabolic activity on PET/CT corresponds with MRI findings about the lumbar spinal column, but there is no significant correlation between severity of MRI findings and radiotracer uptake. Given the moderate agreement between metabolic activity and levels of symptomatic spinal stenosis, further studies are warranted to fully evaluate the diagnostic potential of FDG PET/CT as a surrogate for guiding epidural injections.


Asunto(s)
Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Radiofármacos , Estudios Retrospectivos , Esteroides
20.
J Neural Eng ; 18(4)2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33978599

RESUMEN

Objective.Brain-computer interfaces (BCIs) translate neural activity into control signals for assistive devices in order to help people with motor disabilities communicate effectively. In this work, we introduce a new BCI architecture that improves control of a BCI computer cursor to type on a virtual keyboard.Approach.Our BCI architecture incorporates an external artificial intelligence (AI) that beneficially augments the movement trajectories of the BCI. This AI-BCI leverages past user actions, at both long (100 s of seconds ago) and short (100 s of milliseconds ago) timescales, to modify the BCI's trajectories.Main results.We tested our AI-BCI in a closed-loop BCI simulator with nine human subjects performing a typing task. We demonstrate that our AI-BCI achieves: (1) categorically higher information communication rates, (2) quicker ballistic movements between targets, (3) improved precision control to 'dial in' on targets, and (4) more efficient movement trajectories. We further show that our AI-BCI increases performance across a wide control quality spectrum from poor to proficient control.Significance.This AI-BCI architecture, by increasing BCI performance across all key metrics evaluated, may increase the clinical viability of BCI systems.


Asunto(s)
Interfaces Cerebro-Computador , Dispositivos de Autoayuda , Inteligencia Artificial , Computadores , Electroencefalografía , Humanos , Movimiento , Interfaz Usuario-Computador
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