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1.
Ann Transl Med ; 12(4): 64, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39118954

RESUMEN

Background: Circulating tumor DNA (ctDNA) analysis has been applied in cancer diagnostics including lung cancer. Specifically for the early detection purpose, various modalities of ctDNA analysis have demonstrated their potentials. Such analyses have showed diverse performance across different studies. Methods: We performed a systematic review of original studies published before 1 January 2023. Studies that evaluated ctDNA alone and in combination with other biomarkers for early detection of lung cancer were included. Results: The systematic review analysis included 56 original studies that were aimed for early detection of lung cancer. There were 39 studies for lung cancer only and 17 for pan-cancer early detection. Cancer and control cases included were heterogenous across studies. Different molecular features of ctDNA have been evaluated, including 7 studies on cell-free DNA concentration, 17 on mutation, 29 on methylation, 5 on hydroxymethylation and 8 on fragmentation patterns. Among these 56 studies, 17 have utilised different combinations of the above-mentioned ctDNA features and/or circulation protein markers. For all the modalities, lower sensitivities were reported for the detection of early-stage cancer. Conclusions: The systematic review suggested the clinical utility of ctDNA analysis for early detection of lung cancer, alone or in combination with other biomarkers. Future validation with standardised testing protocols would help integration into clinical care.

3.
ESMO Open ; 9(7): 103626, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38968929

RESUMEN

BACKGROUND: Determining the maximum tolerated dose (MTD) remains the primary objective for the majority of dose-finding oncology trials. Whilst MTD determination often relies upon clinicians to identify dose-limiting toxicities (DLTs) experienced by patients during the trial, research suggests that clinicians may underreport patient's adverse events. Therefore, contemporary practice may be exposed to recommending intolerable doses to patients for further investigation in subsequent trials. There is increasing interest in patients self-assessing their own symptoms using patient-reported outcomes (PROs) in dose-finding trials. DESIGN: We present Utility-PRO-Continual Reassessment Method (U-PRO-CRM), a novel trial design which simultaneously uses clinician-rated and patient-rated DLTs (Clinician-DLTs and Patient-DLTs, respectively) to make dose (de-)escalation decisions and to recommend an MTD. U-PRO-CRM contains the published PRO-CRM as a special case and provides greater flexibility to trade-off the rate of Patient-DLTs and Clinician-DLTs to find an optimal dose. We present simulation results for U-PRO-CRM. RESULTS: For specified trade-offs between Clinician-DLT and Patient-DLT rate, U-PRO-CRM outperforms the PRO-CRM design by identifying the true MTD more often. In the special case where U-PRO-CRM generalises to PRO-CRM, U-PRO-CRM performs as well as its published counterpart. U-PRO-CRM minimises the number of patients overdosed whilst maintaining a similar proportion of patients allocated to the true MTD. CONCLUSIONS: By using a utility-based dose selection approach, U-PRO-CRM offers the flexibility to define a trade-off between the risk of patient-rated and clinician-rated DLTs for an optimal dose. Patient-centric dose-finding strategies, which integrate PROs, are poised to assume an ever more pivotal role in significantly advancing our understanding of treatment tolerability. This bears significant implications in shaping the future landscape of early-phase trials.


Asunto(s)
Dosis Máxima Tolerada , Medición de Resultados Informados por el Paciente , Humanos , Proyectos de Investigación , Relación Dosis-Respuesta a Droga , Neoplasias/tratamiento farmacológico , Ensayos Clínicos como Asunto , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico
4.
Opt Lett ; 48(5): 1124-1127, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36857229

RESUMEN

The heterogeneous integration of a GaN-based photonic integrated circuit (PIC) and an Si-based transimpedance amplifier (TIA) is demonstrated in this work. The monolithic GaN PIC, fabricated from a GaN-on-Si light-emitting diode (LED) wafer, comprises LEDs whose optical outputs are coupled to photodetectors (PD) through suspended waveguides. The PIC chip is mounted onto a printed circuit board together with a TIA chip and two filter chip capacitors, occupying a compact footprint. The components are interconnected directly using wire-bonds to minimize signal delays and attenuation. The integrated system achieves rise and fall times of 2.21 and 2.10 ns, respectively, a transmission delay of 3.54 ns, and a bandwidth exceeding 390 MHz. Transmission of a pseudorandom binary sequence-3 (PRBS-3) signal across the integrated system is also demonstrated at the data transmission rate of 280 Mbit/s with a clearly resolved open eye diagram.

6.
Hong Kong Med J ; 28(1): 33-44, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35086965

RESUMEN

INTRODUCTION: Lifestyle choices may influence health outcomes in cancer survivors. This study of childhood cancer survivors in Hong Kong investigated factors associated with health-protective and health-damaging behaviours; it also examined expectations of a survivorship programme. METHODS: This cross-sectional study recruited survivors of childhood cancer ≥2 years after treatment. Survivors completed a structured questionnaire to report their health practices and the perceived values of survivorship programme components. Multivariable logistic regression analysis was conducted to identify factors associated with health behaviours. RESULTS: Two hundred survivors were recruited (mean age=23.4 ± 8.8 years; mean duration since treatment, 13.4 ± 7.6 years). Comparatively few survivors exercised ≥4 days/week (16.0%), used sun protection (18.0%), and had a balanced diet (38.5%). Furthermore, comparatively few survivors reported that they had not undergone any immunisation (24.5%) or were unsure (18.5%) about their immunisation history. Most adult survivors were never-drinkers (71.0%) and never-smokers (93.0%). Brain tumour survivors were more likely to have unhealthy eating habits, compared with haematological malignancy survivors (odds ratio [OR]=2.45; 95% confidence interval [CI]=1.29-4.68). Lower socioeconomic status was associated with inadequate sun protection (OR=0.20; 95% CI=0.05-0.83), smoking (OR=5.13; 95% CI=1.48-17.75), and exposure to second-hand smoke (OR=3.52; 95% CI=1.42-8.69). Late-effects screening (78.5%) and psychosocial services to address psychological distress (77%) were considered essential components of a survivorship programme. CONCLUSIONS: Despite the low prevalences of health-damaging behaviours, local survivors of childhood cancer are not engaging in health-protective behaviours. A multidisciplinary programme addressing late effects and psychosocial aspects may address the multifaceted needs of this special population.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , Adolescente , Adulto , Supervivientes de Cáncer/psicología , Niño , Estudios Transversales , Conductas Relacionadas con la Salud , Hong Kong/epidemiología , Humanos , Motivación , Neoplasias/psicología , Neoplasias/terapia , Sobrevivientes , Supervivencia , Adulto Joven
7.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34873045

RESUMEN

In the field of circulating cell-free DNA, most of the studies have focused on short DNA molecules (e.g., <500 bp). The existence of long cell-free DNA molecules has been poorly explored. In this study, we demonstrated that single-molecule real-time sequencing allowed us to detect and analyze a substantial proportion of long DNA molecules from both fetal and maternal sources in maternal plasma. Such molecules were beyond the size detection limits of short-read sequencing technologies. The proportions of long cell-free DNA molecules in maternal plasma over 500 bp were 15.5%, 19.8%, and 32.3% for the first, second, and third trimesters, respectively. The longest fetal-derived plasma DNA molecule observed was 23,635 bp. Long plasma DNA molecules demonstrated predominance of A or G 5' fragment ends. Pregnancies with preeclampsia demonstrated a reduction in long maternal plasma DNA molecules, reduced frequencies for selected 5' 4-mer end motifs ending with G or A, and increased frequencies for selected motifs ending with T or C. Finally, we have developed an approach that employs the analysis of methylation patterns of the series of CpG sites on a long DNA molecule for determining its tissue origin. This approach achieved an area under the curve of 0.88 in differentiating between fetal and maternal plasma DNA molecules, enabling the determination of maternal inheritance and recombination events in the fetal genome. This work opens up potential clinical utilities of long cell-free DNA analysis in maternal plasma including noninvasive prenatal testing of monogenic diseases and detection/monitoring of pregnancy-associated disorders such as preeclampsia.


Asunto(s)
Ácidos Nucleicos Libres de Células/sangre , Ácidos Nucleicos Libres de Células/genética , Adulto , Cromosomas/genética , Simulación por Computador , Femenino , Feto , Humanos , Embarazo , Imagen Individual de Molécula
9.
Obes Res Clin Pract ; 14(6): 514-518, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33132075

RESUMEN

BACKGROUND: As the number of individuals with obesity increases, so too will the demand for a precise, cost-effective and safe method to better risk-stratify this heterogenous population. Visceral adipose tissue (VAT) area, a body composition measurement has been associated with the many facets of the metabolic syndrome. AIM: To determine the precision of dual energy X-ray absorptiometry (DXA) in providing body composition measurements, including VAT area, using the Hologic Horizon A scanner. METHOD: Thirty participants (mean age 64 years, 47% male), underwent two sequential body composition scans. The coefficient of variation (CV) and least significant change (LSC) were calculated for android/gynoid ratio, appendicular lean/height2, lean/height2, total body fat and lean mass, total body mass, and subcutaneous adipose tissue (SAT) and VAT area. Participants were stratified according to age (<70 or ≥70 years), body mass index (BMI) (≤30 kg/m2 or >30 kg/m2) and sex (male or female). The CV was calculated for each parameter and then analysed for differences between groups. RESULTS: The CV for all parameters was <3% with the exception of SAT (3.86%). The CV of VAT area was 2.63% with a LSC at 95% confidence of 7.28%. Apart from the CV differences between males and females for android/gynoid ratio (male: 3.56% vs. female: 1.74%, p = 0.01) and SAT area (5.04% vs. 2.46%, p = 0.01), there were no significant differences identified between the calculated CV for all other body composition parameters when participants were stratified by age, BMI and sex. CONCLUSION: DXA scanning, using the Hologic Horizon A system, is capable of providing precise body composition measurements.


Asunto(s)
Composición Corporal , Absorciometría de Fotón , Anciano , Índice de Masa Corporal , Femenino , Humanos , Grasa Intraabdominal , Masculino , Persona de Mediana Edad , Obesidad
10.
Ann Oncol ; 31(11): 1553-1560, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32801017

RESUMEN

BACKGROUND: This multicentre, randomised, double-blinded, placebo-controlled, phase II/III trial aimed to evaluate an oral THC:CBD (tetrahydrocannabinol:cannabidiol) cannabis extract for prevention of refractory chemotherapy-induced nausea and vomiting (CINV). Here we report the phase II component results. PATIENTS AND METHODS: Eligible patients experienced CINV during moderate-to-high emetogenic intravenous chemotherapy despite guideline-consistent antiemetic prophylaxis. Study treatment consisted of one cycle of 1-4 self-titrated capsules of oral THC 2.5 mg/CBD 2.5 mg (TN-TC11M) three times daily, from days -1 to 5, and 1 cycle of matching placebo in a crossover design, then blinded patient preference for a third cycle. The primary end point was the proportion of participants with complete response during 0-120 h from chemotherapy. A total of 80 participants provided 80% power to detect a 20% absolute improvement with a two-sided P value of 0.1. RESULTS: A total of 81 participants were randomised; 72 completing two cycles were included in the efficacy analyses and 78 not withdrawing consent were included in safety analyses. Median age was 55 years (range 29-80 years); 78% were female. Complete response was improved with THC:CBD from 14% to 25% (relative risk 1.77, 90% confidence interval 1.12-2.79, P = 0.041), with similar effects on absence of emesis, use of rescue medications, absence of significant nausea, and summary scores for the Functional Living Index-Emesis (FLIE). Thirty-one percent experienced moderate or severe cannabinoid-related adverse events such as sedation, dizziness, or disorientation, but 83% of participants preferred cannabis to placebo. No serious adverse events were attributed to THC:CBD. CONCLUSION: The addition of oral THC:CBD to standard antiemetics was associated with less nausea and vomiting but additional side-effects. Most participants preferred THC:CBD to placebo. Based on these promising results, we plan to recruit an additional 170 participants to complete accrual for the definitive, phase III, parallel group analysis. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12616001036404; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370473&isReview=true.


Asunto(s)
Antieméticos , Antineoplásicos , Cannabidiol , Cannabis , Náusea , Vómitos , Adulto , Anciano , Anciano de 80 o más Años , Antieméticos/uso terapéutico , Antineoplásicos/uso terapéutico , Australia , Cannabidiol/uso terapéutico , Estudios Cruzados , Método Doble Ciego , Dronabinol/uso terapéutico , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Náusea/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Vómitos/inducido químicamente , Vómitos/tratamiento farmacológico
11.
Thromb Res ; 187: 125-130, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31986475

RESUMEN

BACKGROUND: Evidence for guideline recommendations for the treatment of venous thromboembolism (VTE) during anticoagulant therapy is scarce. We aimed to observe and to describe the management of VTE occurring during anticoagulant therapy. METHODS: This prospective multi-center, observational study included patients with objectively confirmed VTE during anticoagulant therapy (breakthrough event), with a follow-up of 3 months, after the breakthrough event. RESULTS: We registered 121 patients with a breakthrough event, with a mean age of 56 years (range, 19 to 90); 61 were male (50%). Fifty-eight patients (48%) had an active malignancy. At the time of the breakthrough event, 57 patients (47%) were treated with a vitamin K antagonist (VKA), 53 patients (44%) with low-molecular-weight heparin (LMWH) and 11 patients (9%) with direct oral anticoagulants, unfractionated heparin, or VKA plus LMWH. A total of 21 patients (17%) were receiving a subtherapeutic dose of an anticoagulant. The main regimens to treat recurrence in patients on VKA were: switch to LMWH (33%), temporary double treatment with LMWH and VKA (23%), and VKA with a higher target INR (19%). In patients with a breakthrough on LMWH, the most frequently chosen regimen was a permanent dose increase (74%). During 3-month follow-up, 7% of patients had a second breakthrough event and 8% experienced major or clinically relevant non-major bleeding. CONCLUSION: There is wide variation in the management of VTE during anticoagulant treatment, reflecting a heterogeneous and complex clinical situation. Despite intensifying anticoagulation, the risk of a second breakthrough event in this population is 7%.


Asunto(s)
Neoplasias , Tromboembolia Venosa , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/uso terapéutico , Femenino , Heparina , Heparina de Bajo-Peso-Molecular/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Tromboembolia Venosa/tratamiento farmacológico , Vitamina K , Adulto Joven
12.
Surg Endosc ; 34(5): 2000-2006, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31312961

RESUMEN

BACKGROUND: The development of robotic system may help to relieve the difficulties encountered during laparoscopic hepatectomy. A difficulty scoring system (DSS) was developed to assess the difficulty of various laparoscopic liver resection procedures. The aim of this study is to explore if the DSS is applicable in robotic hepatectomy and to compare the outcomes of robotic hepatectomy and laparoscopic hepatectomy among different difficulty levels. METHODS: Clinical data from all consecutive patients who underwent robotic and conventional laparoscopic hepatectomy at the Prince of Wales Hospital, Hong Kong, were prospectively collected and reviewed. The difficulty level of operations was graded using the DSS. Perioperative outcomes of robotic and conventional laparoscopic hepatectomy were compared at each difficulty level. RESULTS: A total of 107 and 94 patients underwent robotic and laparoscopic hepatectomy during the study period, respectively. Among them, 16 and 2 patients were operated for recurrent pyogenic cholangitis, respectively, and were excluded because no mark for tumour location can be assigned. For robotic hepatectomy, a higher DSS was significantly correlated with higher minor complication rate (p = 0.001), more intraoperative blood loss (p = 0.002), longer operation time (p < 0.001) and longer post-operative hospital stay (p < 0.001). The mean DSS scores of robotic and laparoscopic hepatectomy were 4.5 and 3.6, respectively. (p = 0.004). For cases with low (DSS 1-3) and intermediate (DSS 4-6) difficulty level, there was no significant difference in operative blood loss, operation time and overall complications rate. Only 2 cases (2.2%) with high difficulty level were operated with laparoscopic approach while 20% of patients operated with robotic approach had DSS > 6. CONCLUSIONS: DSS significantly correlated with surgical outcomes in patient who underwent robotic hepatectomy. Perioperative outcomes following robotic and conventional laparoscopic hepatectomy were similar in cases with low and intermediate difficulty. However, robotic system allowed minimally invasive approach in cases with higher difficulty level.


Asunto(s)
Hepatectomía/métodos , Laparoscopía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
13.
Hong Kong Med J ; 25(2): 94-101, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30919808

RESUMEN

INTRODUCTION: Enhanced recovery after surgery (ERAS) reduces postoperative length of hospital stay and patient stress response to liver surgery. The aim of the present study was to evaluate the efficacy and feasibility of an ERAS programme for liver resection. METHODS: A multidisciplinary ERAS protocol was implemented for both open and laparoscopic liver resection in a tertiary hospital in Hong Kong. The clinical outcomes of patients who underwent liver resection and underwent the ERAS perioperative programme were compared with those who received a conventional perioperative programme between September 2015 and July 2016. Propensity score matching analysis was used to minimise background differences. RESULTS: A total of 20 patients who underwent liver resection were recruited to the ERAS programme. Their clinical outcomes were compared with another 20 patients who received hepatectomy under a conventional perioperative programme after propensity score matching. The ERAS programme was associated with a significantly shorter length of hospital stay (P=0.033) without an increase in complication rates in patients who underwent open liver resection. There was no such significant association in patients who underwent laparoscopic liver resection. No patients required readmission in this cohort. CONCLUSIONS: The ERAS perioperative programme for liver resection is safe and feasible. It significantly shortened the hospital stay after open liver resection but not after laparoscopic liver resection.


Asunto(s)
Recuperación Mejorada Después de la Cirugía/normas , Hepatectomía/efectos adversos , Laparoscopía , Tiempo de Internación/estadística & datos numéricos , Adulto , Anciano , Estudios de Factibilidad , Femenino , Hepatectomía/mortalidad , Hepatectomía/rehabilitación , Hong Kong , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/prevención & control , Puntaje de Propensión , Estudios Prospectivos , Recuperación de la Función , Centros de Atención Terciaria
14.
Oncogene ; 38(25): 5111-5112, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30867566

RESUMEN

In the published version of this article, the images for cytoplasmic and nuclear FGF7 in MDA-MB-231 cells were duplicated and mistaken for total FGF7 in SKBR-3 and MDA-MB-231 cells.

15.
Climacteric ; 22(6): 589-595, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30896255

RESUMEN

Women with early, estrogen receptor-positive breast cancer are treated with adjuvant endocrine therapy, using aromatase inhibitors or selective estradiol receptor modulators such as tamoxifen, to deprive breast tissue from the deleterious effects of estradiol action, hence improving long-term prognosis. Aromatase inhibitors and, in premenopausal women, tamoxifen accelerate bone loss and increase fracture risk. Therefore, all women commencing endocrine therapy need a targeted work-up to assess the baseline fracture risk, and monitoring of bone health during endocrine therapy should be individualized based on this baseline risk. While high-level evidence specific to early breast cancer is lacking, non-pharmacologic measures to maintain optimal bone health such as weight-bearing exercise and calcium and vitamin D sufficiency should be implemented in all women. Antiresorptive treatment should be initiated in all women with preexisting fragility fractures (including vertebral morphometric fractures) and should be considered in women with areal bone mineral density (BMD) T-scores < -2.0 (or Z-scores in women aged <50 years) or those experiencing rapid bone loss (≥5% per year), taking into consideration the baseline BMD and other risk factors for fracture. Further clinical trial evidence is required to provide definitive guidance regarding criteria to initiate antiresorptive treatment, choice of agents, and duration of treatment, taking into account potential oncologic benefits of antiresorptive therapy on breast cancer-related outcomes.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Supervivientes de Cáncer , Fracturas Óseas/prevención & control , Tamoxifeno/efectos adversos , Inhibidores de la Aromatasa/efectos adversos , Inhibidores de la Aromatasa/farmacología , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Fracturas Óseas/inducido químicamente , Humanos , Factores de Riesgo , Tamoxifeno/farmacología
16.
Hum Reprod ; 33(11): 2141-2149, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30285230

RESUMEN

STUDY QUESTION: Are higher overall and central adiposity associated with reduced fecundability, measured by time-to-pregnancy (TTP), in Asian women? SUMMARY ANSWER: Higher overall adiposity, but not central adiposity, was associated with longer TTP in Asian women. WHAT IS KNOWN ALREADY: High body mass index (BMI) has been associated with a longer TTP, although the associations of body composition and distribution with TTP are less clear. There are no previous studies of TTP in Asian women, who have a relatively higher percentage of body fat and abdominal fat at relatively lower BMI. STUDY DESIGN, SIZE, DURATION: Prospective preconception cohort using data from 477 Asian (Chinese, Malay and Indian) women who were planning to conceive and enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO) study, 2015-2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women's mean age was 30.7 years. Overall adiposity was assessed by BMI, sum of 4-site skinfold thicknesses (SFT) and total body fat percentage (TBF%, measured using air displacement plethysmography); central adiposity was assessed by waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and A body Shape Index (ABSI). Pregnancy occurring within one year from recruitment was ascertained by ultrasonography. Those who did not conceive within one year of recruitment, were lost to follow-up, or initiated fertility treatment were censored. TTP was measured in cycles. Discrete-time proportional hazards models were used to estimate the fecundability ratio (FR) and 95% confidence interval (CI) for each anthropometric measure in association with fecundability, adjusting for confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to women with a normal BMI of 18.5-22.9 kg/m2, women with higher BMI of 23-27.4 and ≥27.5 kg/m2 showed lower FR of 0.66 (95% CI 0.45, 0.97) and 0.53 (0.31, 0.89), respectively. Compared to women in the lowest quartile of SFT (25-52.9 mm), those in the highest quartile of ≥90.1 mm showed lower FR of 0.58 (95% CI 0.36, 0.95). Compared to women in the lowest quartile of TBF% (13.6-27.2%), those in the upper two quartiles of 33.0-39.7% and ≥39.8% showed lower FR of 0.56 (95% CI 0.32, 0.98) and 0.43 (0.24, 0.80), respectively. Association of high BMI with reduced fecundability was particularly evident among nulliparous women. Measures of central adiposity (WC, WHR, WHtR, ABSI) were not associated with fecundability. LIMITATIONS REASONS FOR CAUTION: Small sample size could restrict power of analysis.The analysis was confined to planned pregnancies, which could limit generalizability of findings to non-planned pregnancies, estimated at around 44% in Singapore. Information on the date of last menstrual period for each month was not available, hence the accuracy of self-reported menstrual cycle length could not be validated, potentially introducing error into TTP estimation. Measures of exposures and covariates such as cycle length were not performed repeatedly over time; cycle length might have changed during the period before getting pregnant. WIDER IMPLICATIONS OF THE FINDINGS: Other than using BMI as the surrogate measure of body fat, we provide additional evidence showing that higher amounts of subcutaneous fat that based on the measure of SFT at the sites of biceps, triceps, suprailiac and subscapular, and TBF% are associated with longer TTP. Achieving optimal weight and reducing total percentage body fat may be a potential intervention target to improve female fertility. The null results observed between central adiposity and TTP requires confirmation in further studies. STUDY FUNDING/COMPETING INTEREST(S): This research is supported by Singapore National Research Foundation under its Translational and Clinical Research Flagship Programme and administered by the Singapore Ministry of Health's National Medical Research Council, (NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014). Additional funding is provided by the Singapore Institute for Clinical Sciences, Agency for Science Technology and Research (A*STAR), Singapore. Y.S.C., K.M.G., F.Y. and Y.S.L. have received reimbursement to speak at conferences sponsored by companies selling nutritional products. Y.S.C., K.M.G. and S.Y.C. are part of an academic consortium that has received research funding from Abbott, Nutrition, Nestle and Danone. Other authors declared no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Adiposidad/fisiología , Infertilidad Femenina/etiología , Tiempo para Quedar Embarazada , Adiposidad/etnología , Adulto , Pueblo Asiatico/estadística & datos numéricos , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Estimación de Kaplan-Meier , Obesidad/complicaciones , Embarazo , Estudios Prospectivos , Singapur/epidemiología
17.
AJNR Am J Neuroradiol ; 39(10): 1919-1925, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30213807

RESUMEN

BACKGROUND AND PURPOSE: Survivors of acute lymphoblastic leukemia are at risk for neurocognitive deficits and leukoencephalopathy. We performed a longitudinal assessment of leukoencephalopathy and its associations with long-term brain microstructural white matter integrity and neurocognitive outcomes in survivors of childhood acute lymphoblastic leukemia treated on a modern chemotherapy-only protocol. MATERIALS AND METHODS: One hundred seventy-three survivors of acute lymphoblastic leukemia (49% female), treated on a chemotherapy-only protocol, underwent brain MR imaging during active therapy and repeat imaging and neurocognitive testing at follow-up (median, 13.5 years of age; interquartile range, 10.7-17.6 years; median time since diagnosis, 7.5 years; interquartile range, 6.3-9.1 years). Persistence of leukoencephalopathy was examined in relation to demographic and treatment data and to brain DTI in major fiber tracts and neurocognitive testing at follow-up. RESULTS: Leukoencephalopathy was found in 52 of 173 long-term survivors (30.0%) and persisted in 41 of 52 (78.8%) who developed it during therapy. DTI parameters were associated with leukoencephalopathy in multiple brain regions, including the corona radiata (fractional anisotropy, P = .001; mean diffusivity, P < .001), superior longitudinal fasciculi (fractional anisotropy, P = .02; mean diffusivity, P < .001), and superior fronto-occipital fasciculi (fractional anisotropy, P = .006; mean diffusivity, P < .001). Mean diffusivity was associated with neurocognitive impairment including in the genu of the corpus callosum (P = .04), corona radiata (P = .02), and superior fronto-occipital fasciculi (P = .02). CONCLUSIONS: Leukoencephalopathy during active therapy and neurocognitive impairment at long-term follow-up are associated with microstructural white matter integrity. DTI may be more sensitive than standard MR imaging for detection of clinically consequential white matter abnormalities in childhood acute lymphoblastic leukemia survivors treated with chemotherapy and in children undergoing treatment.


Asunto(s)
Antineoplásicos/efectos adversos , Leucoencefalopatías/inducido químicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Sustancia Blanca/patología , Adolescente , Supervivientes de Cáncer , Niño , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Leucoencefalopatías/diagnóstico por imagen , Leucoencefalopatías/patología , Masculino , Neuroimagen/métodos , Sustancia Blanca/diagnóstico por imagen
18.
IBM J Res Dev ; 62(1)2018.
Artículo en Inglés | MEDLINE | ID: mdl-29875505

RESUMEN

An increasing number of people use mobile devices to monitor their behavior, such as exercise, and record their health status, such as psychological stress. However, these devices rarely provide ongoing support to help users understand how their behavior contributes to changes in their health status. To address this challenge, we aim to develop an interpretable policy for physical activity recommendations that reduce a user's perceived psychological stress, over a given time horizon. We formulate this problem as a sequential decision-making problem and solve it using a new method that we refer to as threshold Q-learning (TQL). The advantage of the TQL method over traditional Q-learning is that it is "doubly robust" and interpretable. This interpretability is achieved by making model assumptions and incorporating threshold selection into the learning process. Our simulation results indicate that the TQL method performs better than the Q-learning method given model misspecification. Our analyses are performed on data collected from 79 healthy adults over a 7 week period, where the data comprise physical activity patterns collected from mobile devices and self-assessed stress levels of the users. This work serves as a first step toward a computational health coaching solution for mobile device users.

19.
Appl Opt ; 57(10): 2452-2458, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29714220

RESUMEN

We demonstrate the fabrication of InGaN/GaN stripe-shaped light-emitting diodes (LEDs) in flip-chip packaging (FC-LED) and vertically mounted packaging (VM-LED). Compared to conventionally packaged LEDs, these packaging schemes enhance light output and emission divergence in ways favorable for general lighting applications. The FC-LED can sustain efficiency at high current operations due to effective heat sinking, while the VM-LED excels at light extraction efficiency due to the exposure of two large emission surfaces. Together with the properties of low luminous exitance and emission uniformity, the stripe-shaped LEDs are ideal for the assembly of luminaires. An LED light tube comprising a continuous linear array of 10 stripe-shaped LED chips has been assembled. The optical performance of the light tube is compared to another light tube assembled with conventional square-shaped LED chips (with and without external diffuser) by confocal microscopy. It is found that emission uniformity of the stripe-shaped LED tube is significantly improved, with a threefold increase in illumination area, without efficiency loss associated with diffusers.

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