Publications by authors named "C Y Choo"

236 Publications

A single-center pilot study in Malaysia on the clinical utility of whole-exome sequencing for inborn errors of immunity.

Clin Exp Immunol 2021 Jun 1. Epub 2021 Jun 1.

Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.

Primary immunodeficiency diseases refer to inborn errors of immunity (IEI) that affect the normal development and function of the immune system. The phenotypic and genetic heterogeneity of IEI have made their diagnosis challenging. Hence, whole-exome sequencing (WES) was employed in this pilot study to identify the genetic etiology of 30 pediatric patients clinically diagnosed with IEI. The potential causative variants identified by WES were validated using Sanger sequencing. Genetic diagnosis was attained in 46.7% (14/30) of the patients and categorized into autoinflammatory disorders (n=3), diseases of immune dysregulation (n=3), defects in intrinsic and innate immunity (n=3), predominantly antibody deficiencies (n=2), combined immunodeficiencies with associated and syndromic features (n=2), and immunodeficiencies affecting cellular and humoral immunity (n=1). Of the 15 genetic variants identified, two were novel variants. Genetic findings differed from the provisional clinical diagnoses in seven cases (50.0%). This study showed that WES enhances the capacity to diagnose IEI, allowing more patients to receive appropriate therapy and disease management.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/cei.13626DOI Listing
June 2021

The prognostic value, sensitivity, and specificity of multiparametric magnetic resonance imaging before salvage radiotherapy for prostate cancer.

Radiother Oncol 2021 May 21;161:9-15. Epub 2021 May 21.

Department of Radiation Oncology, Mayo Clinic, Rochester, USA.

Aim: To determine the operational characteristics of pelvic magnetic resonance imaging (MRI) prior to salvage radiation therapy (SRT) for biochemically recurrent prostate cancer following radical prostatectomy.

Methods And Materials: We reviewed the medical records of 386 patients who underwent MRI prior to SRT. We assessed associations of pre-SRT MRI findings with biochemical recurrence (BCR), distant metastasis (DM), prostate cancer-specific mortality (PCSM), and salvage androgen deprivation therapy (ADT) use following SRT. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI for detecting local recurrence were also calculated.

Results: Pre-SRT MRI was positive for local recurrence in 216 patients (56%), indeterminate in 46 (12%), and negative in 124 (32%). On univariate analysis, BCR following SRT was significantly less likely for patients with positive (HR: 0.58, 95% CI: 0.42-0.8) or indeterminate (HR: 0.6: 0.36-1) MRI findings, compared to patients with negative imaging (p = 0.003). These associations remained significant on multivariate analysis (p < 0.05) and across pre-SRT PSA groups. For the entire cohort, the sensitivity of MRI for local recurrence was 61.0% (53.5-68.1%), specificity 60.0% (44.3-73.0%), PPV 86.1% (78.9-91.5%) and NPV 27.6% (19.0-37.5%). Sensitivity of MRI was better in men with higher pre-SRT PSA (80.0% for PSA > 1.0), and specificity was improved with lower pre-SRT PSA (73.9% for PSA 0.1-0.5).

Conclusions: Positive or indeterminate MRI findings prior to SRT were associated with improved biochemical control following SRT, across PSA levels. The sensitivity and specificity of MRI for local recurrence were 61% and 58.7%, respectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.radonc.2021.05.015DOI Listing
May 2021

Effect of Exclusion Diets on Symptom Severity and the Gut Microbiota in Patients with Irritable Bowel Syndrome.

Clin Gastroenterol Hepatol 2021 May 19. Epub 2021 May 19.

G Oppenheimer Center for Neurobiology of Stress and Resilience; Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California, Los Angeles, United States,. Electronic address:

Background & Aims: Altered fecal microbiota have been reported in IBS, although studies vary which could be due to dietary effects. Many IBS patients may eliminate certain foods because of their symptoms, which in turn may alter fecal microbiota diversity and composition. This study aims were to determine if dietary patterns were associated with IBS, symptoms, and fecal microbiota differences reported in IBS.

Methods: 346 IBS participants and 170 healthy controls (HCs) completed a Diet Checklist reflecting the diet(s) consumed most frequently. An exclusion diet was defined as a diet that eliminated food components by choice. Within this group, a gluten-free, dairy-free, or low FODMAP diet was further defined as restrictive as they are often implicated to reduce symptoms. Stool samples were obtained from 171 IBS patients and 98 HCs for 16S rRNA gene sequencing and microbial composition analysis.

Results: Having IBS symptoms was associated with consuming a restrictive diet (27.17% of IBS patients vs 7.65% of HCs; OR 3.25; 95% CI 1.66-6.75; p-value 0.006). IBS participants on an exclusion or restrictive diet reported more severe IBS symptoms (p=0.042 and p=0.029 respectively). The composition of the microbiota in IBS patients varied depending on the diet consumed. IBS participants on an exclusion diet had a greater abundance of Lachnospira and a lower abundance of Eubacterium (q-values<0.05) and those on a restrictive diet had a lower abundance of Lactobacillus (q-value <0.05).

Conclusions: Restrictive diets are likely consumed more by IBS patients than HCs to reduce GI symptom severity. Dietary patterns influence the composition of fecal microbiota and may explain some of the differences between IBS and HCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cgh.2021.05.027DOI Listing
May 2021

Patterns of Clinical Progression in Radiorecurrent High-risk Prostate Cancer.

Eur Urol 2021 May 10. Epub 2021 May 10.

Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

The natural history of radiorecurrent high-risk prostate cancer (HRPCa) is not well-described. To better understand its clinical course, we evaluated rates of distant metastases (DM) and prostate cancer-specific mortality (PCSM) in a cohort of 978 men with radiorecurrent HRPCa who previously received either external beam radiation therapy (EBRT, n = 654, 67%) or EBRT + brachytherapy (EBRT + BT, n = 324, 33%) across 15 institutions from 1997 to 2015. In men who did not die, median follow-up after treatment was 8.9 yr and median follow-up after biochemical recurrence (BCR) was 3.7 yr. Local and systemic therapy salvage, respectively, were delivered to 21 and 390 men after EBRT, and eight and 103 men after EBRT + BT. Overall, 435 men developed DM, and 248 were detected within 1 yr of BCR. Measured from time of recurrence, 5-yr DM rates were 50% and 34% after EBRT and EBRT + BT, respectively. Measured from BCR, 5-yr PCSM rates were 27% and 29%, respectively. Interval to BCR was independently associated with DM (p < 0.001) and PCSM (p < 0.001). These data suggest that radiorecurrent HRPCa has an aggressive natural history and that DM is clinically evident early after BCR. These findings underscore the importance of further investigations into upfront risk assessment and prompt systemic evaluation upon recurrence in HRPCa. PATIENT SUMMARY: High-risk prostate cancer that recurs after radiation therapy is an aggressive disease entity and spreads to other parts of the body (metastases). Some 60% of metastases occur within 1 yr. Approximately 30% of these patients die from their prostate cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.eururo.2021.04.035DOI Listing
May 2021

Perceptual-motor skill transfer: Multidimensionality and specificity of both general and specific transfers.

Acta Psychol (Amst) 2021 Jun 3;217:103321. Epub 2021 May 3.

National Institute of Education, Nanyang Technological University, Singapore.

This paper aims to investigate perceptual-motor skill transfer, both through the specific as well as the general aspect of skill transfer. Specifically, we examined differences in skill transfer that occurred between participants who are skilled in practicing a perceptual motor activity involving striking with an implement and participants who are skilled in their own sports but are novice to striking task (i.e., batting an immobile ball). Skill transfer was assessed through the effect of practicing a new, novel task on the performance (ball velocity), intrinsic behavior (elbow and shoulder kinematic) as well as on the impetus for exploratory behavior (variability of elbow and shoulder kinematics) in the two groups of participants (n = 8 for each group), with reference to another group of expert participants (n = 8) for this batting task. Results showed that positive skill transfer was present and was multidimensional in the group of participants who have experience in using an implement in striking tasks. In addition, both specific transfer as well as general transfer were dependent on the task dynamics. More precisely, positive transfer was observed both through a sharing of similar movement patterns, an impetus for exploration and a direct transfer of performance in a novel task between groups who have experience in using an implement in striking tasks.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.actpsy.2021.103321DOI Listing
June 2021